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1. Intermuscular technique for implantation of the subcutaneous implantable defibrillator: a propensity-matched case-control study

Author

Botto, G, Ziacchi, M, Nigro, G, D'Onofrio, A, Dello Russo, A, Francia, P, Viani, S, Pisano, E, Bisignani, G, Caravati, F, Migliore, F, De Filippo, P, Ottaviano, L, Rordorf, R, Manzo, M, Canevese, F, Lovecchio, M, Valsecchi, S, Checchi, L, Casale, M, Schintu, B, Scalone, A, Tola, G, Setzu, A, Curcio, A, Santoro, A, Baiocchi, C, Gentilini, R, Lunghetti, S, Solimene, F, Shopova, G, Schillaci, V, Arestia, A, Agresta, A, Bianchi, S, Rossi, P, Cauti, F, La Greca, C, Pecora, D, Ammirati, F, Santini, L, Mahfouz, K, Colaiaco, C, Vicentini, A, Savastano, S, Petracci, B, Sanzo, A, Baldi, E, Casula, M, Perego, G, Rella, V, Bianchi, V, Tavoletta, V, De Vivo, S, Palmisano, P, Accogli, M, Milanese, G, Pepi, P, Nicolis, D, Mariani, M, Pagani, M, Bonfantino, M, Caccavo, V, Grimaldi, M, Katsouras, G, Forleo, G, Chieffo, E, Tavarelli, E, Brambilla, R, Pani, A, Giammaria, M, Lucciola, M, Amellone, C, Uran, C, Baroni, M, Ferrari, P, Leidi, C, Drago, F, Silvetti, M, Pazzano, V, Russo, S, Remoli, R, Battipaglia, I, Cazzoli, I, Saputo, F, Devecchi, C, Barbonaglia, L, Viscusi, M, Brignoli, M, Mattera, A, Pedretti, S, Lupi, A, Tommasi, S, Kol, A, Gatto, M, Persi, A, Gonella, A, Rossetti, G, Menardi, E, Rossini, R, Notarstefano, P, Nesti, M, Fraticelli, A, Carreras, G, Donzelli, S, Marini, C, Tordini, A, Lazzari, L, Sartori, P, Di Donna, P, Mascia, G, Capogrosso, P, Magliano, P, Colimodio, M, Sala, S, Mazzone, P, Della Bella, P, Coppolino, A, Arena, G, Borrello, V, Ratti, M, Bartoli, C, Palano, F, Adduci, C, Torriglia, A, Laffi, M, Esposito, C, Giano, A, Franculli, F, Pangallo, A, De Bonis, S, Sarubbi, B, Colonna, D, Correra, A, Romeo, E, Rapacciuolo, A, Liguori, V, Viggiano, A, Strisciullo, T, Biffi, M, Diemberger, I, Martignani, C, Piro, A, Lavalle, C, Magnocavallo, M, Ricciardi, D, Calabrese, V, Gioia, F, Picarelli, F, Licciardello, G, Busacca, G, Calvi, V, Lamberti, F, Lumia, G, Bellini, C, Bianchi, C, Savarese, G, Andreoli, C, Pimpinicchio, L, Pellegrini, D, Giorgi, D, Bovenzi, Busoni, F, Daleffe, E, Facchin, D, Rebellato, L, Stifano, G, Magliano, G, Sergi, D, Barone, L, Morgagni, R, Casella, M, Guerra, F, Cipolletta, L, Molini, S, De Lucia, R, Di Cori, A, Grifoni, G, Paperini, L, Segreti, L, Soldati, E, Zucchelli, G, Russo, V, Rago, A, Ammendola, E, Papa, A, Pieragnoli, P, Ricciardi, G, Perrotta, L, Botto G. L., Ziacchi M., Nigro G., D'Onofrio A., Dello Russo A., Francia P., Viani S., Pisano E., Bisignani G., Caravati F., Migliore F., De Filippo P., Ottaviano L., Rordorf R., Manzo M., Canevese F. L., Lovecchio M., Valsecchi S., Checchi L., Casale M. C., Schintu B., Scalone A., Tola G., Setzu A., Curcio A., Santoro A., Baiocchi C., Gentilini R., Lunghetti S., Solimene F., Shopova G., Schillaci V., Arestia A., Agresta A., Bianchi S., Rossi P., Cauti F. M., La Greca C., Pecora D., Ammirati F., Santini L., Mahfouz K., Colaiaco C., Vicentini A., Savastano S., Petracci B., Sanzo A., Baldi E., Casula M., Perego G. B., Rella V., Bianchi V., Tavoletta V., De Vivo S., Palmisano P., Accogli M., Milanese G., Pepi P., Nicolis D., Mariani M., Pagani M., Bonfantino M. V., Caccavo V., Grimaldi M., Katsouras G., Forleo G. B., Chieffo E., Tavarelli E., Brambilla R., Pani A., Giammaria M., Lucciola M. T., Amellone C., Uran C., Baroni M., Ferrari P., Leidi C., Drago F., Silvetti M. S., Pazzano V., Russo S., Remoli R., Battipaglia I., Cazzoli I., Saputo F., Devecchi C., Barbonaglia L., Viscusi M., Brignoli M., Mattera A., Pedretti S., Lupi A., Tommasi S., Kol A., Gatto M. C., Persi A., Gonella A., Rossetti G., Menardi E., Rossini R., Notarstefano P., Nesti M., Fraticelli A., Carreras G., Donzelli S., Marini C., Tordini A., Lazzari L., Sartori P., Di Donna P., Mascia G., Capogrosso P., Magliano P., Colimodio M., Sala S., Mazzone P., Della Bella P., Coppolino A., Arena G., Borrello V., Ratti M., Bartoli C., Palano F., Adduci C., Torriglia A., Laffi M., Esposito C., Giano A., Franculli F., Pangallo A., De Bonis S., Sarubbi B., Colonna D., Correra A., Romeo E., Rapacciuolo A., Liguori V., Viggiano A., Strisciullo T., Biffi M., Diemberger I., Martignani C., Piro A., Lavalle C., Magnocavallo M., Mariani M. V., Ricciardi D., Calabrese V., Gioia F., Picarelli F., Licciardello G., Busacca G., Calvi V. I., Lamberti F., Lumia G., Bellini C., Bianchi C., Savarese G., Andreoli C., Pimpinicchio L., Pellegrini D., Giorgi D., Busoni F., Daleffe E., Facchin D., Rebellato L., Stifano G., Magliano G., Sergi D., Barone L., Morgagni R., Casella M., Guerra F., Cipolletta L., Molini S., De Lucia R., Di Cori A., Grifoni G., Paperini L., Segreti L., Soldati E., Zucchelli G., Russo V., Rago A., Ammendola E., Papa A., Pieragnoli P., Ricciardi G., Perrotta L., Botto, G, Ziacchi, M, Nigro, G, D'Onofrio, A, Dello Russo, A, Francia, P, Viani, S, Pisano, E, Bisignani, G, Caravati, F, Migliore, F, De Filippo, P, Ottaviano, L, Rordorf, R, Manzo, M, Canevese, F, Lovecchio, M, Valsecchi, S, Checchi, L, Casale, M, Schintu, B, Scalone, A, Tola, G, Setzu, A, Curcio, A, Santoro, A, Baiocchi, C, Gentilini, R, Lunghetti, S, Solimene, F, Shopova, G, Schillaci, V, Arestia, A, Agresta, A, Bianchi, S, Rossi, P, Cauti, F, La Greca, C, Pecora, D, Ammirati, F, Santini, L, Mahfouz, K, Colaiaco, C, Vicentini, A, Savastano, S, Petracci, B, Sanzo, A, Baldi, E, Casula, M, Perego, G, Rella, V, Bianchi, V, Tavoletta, V, De Vivo, S, Palmisano, P, Accogli, M, Milanese, G, Pepi, P, Nicolis, D, Mariani, M, Pagani, M, Bonfantino, M, Caccavo, V, Grimaldi, M, Katsouras, G, Forleo, G, Chieffo, E, Tavarelli, E, Brambilla, R, Pani, A, Giammaria, M, Lucciola, M, Amellone, C, Uran, C, Baroni, M, Ferrari, P, Leidi, C, Drago, F, Silvetti, M, Pazzano, V, Russo, S, Remoli, R, Battipaglia, I, Cazzoli, I, Saputo, F, Devecchi, C, Barbonaglia, L, Viscusi, M, Brignoli, M, Mattera, A, Pedretti, S, Lupi, A, Tommasi, S, Kol, A, Gatto, M, Persi, A, Gonella, A, Rossetti, G, Menardi, E, Rossini, R, Notarstefano, P, Nesti, M, Fraticelli, A, Carreras, G, Donzelli, S, Marini, C, Tordini, A, Lazzari, L, Sartori, P, Di Donna, P, Mascia, G, Capogrosso, P, Magliano, P, Colimodio, M, Sala, S, Mazzone, P, Della Bella, P, Coppolino, A, Arena, G, Borrello, V, Ratti, M, Bartoli, C, Palano, F, Adduci, C, Torriglia, A, Laffi, M, Esposito, C, Giano, A, Franculli, F, Pangallo, A, De Bonis, S, Sarubbi, B, Colonna, D, Correra, A, Romeo, E, Rapacciuolo, A, Liguori, V, Viggiano, A, Strisciullo, T, Biffi, M, Diemberger, I, Martignani, C, Piro, A, Lavalle, C, Magnocavallo, M, Ricciardi, D, Calabrese, V, Gioia, F, Picarelli, F, Licciardello, G, Busacca, G, Calvi, V, Lamberti, F, Lumia, G, Bellini, C, Bianchi, C, Savarese, G, Andreoli, C, Pimpinicchio, L, Pellegrini, D, Giorgi, D, Bovenzi, Busoni, F, Daleffe, E, Facchin, D, Rebellato, L, Stifano, G, Magliano, G, Sergi, D, Barone, L, Morgagni, R, Casella, M, Guerra, F, Cipolletta, L, Molini, S, De Lucia, R, Di Cori, A, Grifoni, G, Paperini, L, Segreti, L, Soldati, E, Zucchelli, G, Russo, V, Rago, A, Ammendola, E, Papa, A, Pieragnoli, P, Ricciardi, G, Perrotta, L, Botto G. L., Ziacchi M., Nigro G., D'Onofrio A., Dello Russo A., Francia P., Viani S., Pisano E., Bisignani G., Caravati F., Migliore F., De Filippo P., Ottaviano L., Rordorf R., Manzo M., Canevese F. L., Lovecchio M., Valsecchi S., Checchi L., Casale M. C., Schintu B., Scalone A., Tola G., Setzu A., Curcio A., Santoro A., Baiocchi C., Gentilini R., Lunghetti S., Solimene F., Shopova G., Schillaci V., Arestia A., Agresta A., Bianchi S., Rossi P., Cauti F. M., La Greca C., Pecora D., Ammirati F., Santini L., Mahfouz K., Colaiaco C., Vicentini A., Savastano S., Petracci B., Sanzo A., Baldi E., Casula M., Perego G. B., Rella V., Bianchi V., Tavoletta V., De Vivo S., Palmisano P., Accogli M., Milanese G., Pepi P., Nicolis D., Mariani M., Pagani M., Bonfantino M. V., Caccavo V., Grimaldi M., Katsouras G., Forleo G. B., Chieffo E., Tavarelli E., Brambilla R., Pani A., Giammaria M., Lucciola M. T., Amellone C., Uran C., Baroni M., Ferrari P., Leidi C., Drago F., Silvetti M. S., Pazzano V., Russo S., Remoli R., Battipaglia I., Cazzoli I., Saputo F., Devecchi C., Barbonaglia L., Viscusi M., Brignoli M., Mattera A., Pedretti S., Lupi A., Tommasi S., Kol A., Gatto M. C., Persi A., Gonella A., Rossetti G., Menardi E., Rossini R., Notarstefano P., Nesti M., Fraticelli A., Carreras G., Donzelli S., Marini C., Tordini A., Lazzari L., Sartori P., Di Donna P., Mascia G., Capogrosso P., Magliano P., Colimodio M., Sala S., Mazzone P., Della Bella P., Coppolino A., Arena G., Borrello V., Ratti M., Bartoli C., Palano F., Adduci C., Torriglia A., Laffi M., Esposito C., Giano A., Franculli F., Pangallo A., De Bonis S., Sarubbi B., Colonna D., Correra A., Romeo E., Rapacciuolo A., Liguori V., Viggiano A., Strisciullo T., Biffi M., Diemberger I., Martignani C., Piro A., Lavalle C., Magnocavallo M., Mariani M. V., Ricciardi D., Calabrese V., Gioia F., Picarelli F., Licciardello G., Busacca G., Calvi V. I., Lamberti F., Lumia G., Bellini C., Bianchi C., Savarese G., Andreoli C., Pimpinicchio L., Pellegrini D., Giorgi D., Busoni F., Daleffe E., Facchin D., Rebellato L., Stifano G., Magliano G., Sergi D., Barone L., Morgagni R., Casella M., Guerra F., Cipolletta L., Molini S., De Lucia R., Di Cori A., Grifoni G., Paperini L., Segreti L., Soldati E., Zucchelli G., Russo V., Rago A., Ammendola E., Papa A., Pieragnoli P., Ricciardi G., and Perrotta L.

Abstract

Aims A previous randomized study demonstrated that the subcutaneous implantable cardioverter defibrillator (S-ICD) was noninferior to transvenous ICD with respect to device-related complications and inappropriate shocks. However, that was performed prior to the widespread adoption of pulse generator implantation in the intermuscular (IM) space instead of the traditional subcutaneous (SC) pocket. The aim of this analysis was to compare survival from device-related complications and inappropriate shocks between patients who underwent S-ICD implantation with the generator positioned in an IM position in comparison with an SC pocket. Methods and results We analysed 1577 consecutive patients who had undergone S-ICD implantation from 2013 to 2021 and were followed up until December 2021. Subcutaneous patients (n = 290) were propensity matched with patients of the IM group (n = 290), and their outcomes were compared. : During a median follow-up of 28 months, device-related complications were reported in 28 (4.8%) patients and inappropriate shocks were reported in 37 (6.4%) patients. The risk of complication was lower in the matched IM group than in the SC group [hazard ratio 0.41, 95% confidence interval (CI) 0.17-0.99, P = 0.041], as well as the composite of complications and inappropriate shocks (hazard ratio 0.50, 95% CI 0.30-0.86, P = 0.013). The risk of appropriate shocks was similar between groups (hazard ratio 0.90, 95% CI 0.50-1.61, P = 0.721). There was no significant interaction between generator positioning and variables such as gender, age, body mass index, and ejection fraction. Conclusion Our data showed the superiority of the IM S-ICD generator positioning in reducing device-related complications and inappropriate shocks.

Published
2023

7. Folates dysmetabolism promotes atrial cardiomyopathy/fibrillation through a cardiac-bone marrow networking involving endothelial progenitor cell dysfunction and erythropoiesis diversion

Author

Sgarra, L, primary, Caccavo, VP, additional, Katsouras, G, additional, Di Monaco, A, additional, Quadrini, F, additional, Vitulano, N, additional, Troisi, F, additional, Solimando, A, additional, Cicco, S, additional, Nacci, C, additional, Potenza, MA, additional, Desantis, V, additional, Vacca, A, additional, Montagnani, M, additional, and Grimaldi, M, additional

Published
2022
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10. CARDIOPULMONARY SUPPORT WITH EXTRACORPOREAL MEMBRANE OXYGENATION (ECMO) DURING CATHETER ABLATION OF VENTRICULAR FIBRILLATION: A CASE REPORT

Author

Perniciaro, V, Troisi, F, Katsouras, G, Quadrini, F, Di Monaco, A, and Grimaldi, M

Abstract

The clinical case deals with a 46–year–old man, severely obese and suffering from type II diabetes mellitus and arterial hypertension, a smoker. He was admitted to our department for iterative ventricular fibrillation (VF) following a recent acute myocardial infarction with ST–segment elevation treated with percutaneous coronary angioplasty (PTCA) and implantation of drug–eluting stents on the anterior interventricular. Control coronary angiography showed good results of previous PTCA. On the echocardiogram, left ventricular pump function moderately reduced (EF 45%) with district alterations of the kinetics and aneurysmal dilatation of the ascending aorta. During hospitalization, iterative episodes of VF despite maximal antiarrhythmic therapy, promptly treated with DC shock. Continuous telemetry monitoring showed frequent early premature ventricular complex (PVC) triggering VF episodes. A 12–lead Holter ECG was performed to better identify the morphology of these PVC, documenting PVC of morphology compatible with origin from Purkinjie fibres. An electrophysiological study and mapping of the left ventricle were performed with extracorporeal membrane oxygenation (ECMO) support. During mapping of the middle left interventricular septum, VF occurred several times and was promptly treated with DC shock. In this area have been documented Purkinje fibers and low voltage and multifragmented areas; ablation was then performed by delivering radiofrequency in this area until the all potentials were completely eliminated. After ablation, no more ventricular arrhythmias were induced. Cardiac magnetic resonance imaging was performed which showed large areas of late gadolinium enhancement. The patient underwent automatic defibrillator implantation. Ventricular arrhythmias were no longer documented during telemetric monitoring. In this complex case of significant arrhythmic instability in ischemic heart disease with moderate left ventricular pump dysfunction, ECMO assistance allowed us to effectively and safely perform the ablation of the arrhythmic substrate triggering the iterative episodes of VF.

Published
2024
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11. Multi-proxy evidence of Holocene paleoceanographic and paleoclimatic instability in the NE Mediterranean: connections to global-scale variability

Author

Gogou, Alexandra, Triantaphyllou, Maria V., Bouloubassi, Ioanna, Emeis, K.-C., Katsouras, G., Dimiza, Margarita D., Kouli, K., Parinos, C., Möbius, J., Rousakis, G., Athanasiou, M., Lykousis, V., Biogéochimie-Traceurs-Paléoclimat (BTP), Laboratoire d'Océanographie et du Climat : Expérimentations et Approches Numériques (LOCEAN), Muséum national d'Histoire naturelle (MNHN)-Institut de Recherche pour le Développement (IRD)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Institut Pierre-Simon-Laplace (IPSL (FR_636)), École normale supérieure - Paris (ENS-PSL), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris Diderot - Paris 7 (UPD7)-École polytechnique (X)-Centre National d'Études Spatiales [Toulouse] (CNES)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-École normale supérieure - Paris (ENS-PSL), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris Diderot - Paris 7 (UPD7)-École polytechnique (X)-Centre National d'Études Spatiales [Toulouse] (CNES)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-Muséum national d'Histoire naturelle (MNHN)-Institut de Recherche pour le Développement (IRD)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Institut Pierre-Simon-Laplace (IPSL (FR_636)), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris Diderot - Paris 7 (UPD7)-École polytechnique (X)-Centre National d'Études Spatiales [Toulouse] (CNES)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS), Institut de Recherche pour le Développement (IRD)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Muséum national d'Histoire naturelle (MNHN)-Institut Pierre-Simon-Laplace (IPSL (FR_636)), École normale supérieure - Paris (ENS Paris), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris Diderot - Paris 7 (UPD7)-École polytechnique (X)-Centre National d'Études Spatiales [Toulouse] (CNES)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-École normale supérieure - Paris (ENS Paris), and Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris Diderot - Paris 7 (UPD7)-École polytechnique (X)-Centre National d'Études Spatiales [Toulouse] (CNES)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Muséum national d'Histoire naturelle (MNHN)-Institut Pierre-Simon-Laplace (IPSL (FR_636))

Subjects
[PHYS.PHYS.PHYS-GEO-PH]Physics [physics]/Physics [physics]/Geophysics [physics.geo-ph], ComputingMilieux_MISCELLANEOUS
Abstract

International audience

Published
2014

13. Holocene climate variability and environmental changes in the NE Mediterranean Sea along a N-S transect

Author

Gogou, Alexandra, Bouloubassi, Ioanna, Emeis, K.-C., Triantaphyllou, M., Katsouras, G., Rousakis, G., Lykousis, V., Laboratoire d'Océanographie et du Climat : Expérimentations et Approches Numériques (LOCEAN), Muséum national d'Histoire naturelle (MNHN)-Institut de Recherche pour le Développement (IRD)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Institut Pierre-Simon-Laplace (IPSL (FR_636)), École normale supérieure - Paris (ENS-PSL), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris Diderot - Paris 7 (UPD7)-École polytechnique (X)-Centre National d'Études Spatiales [Toulouse] (CNES)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-École normale supérieure - Paris (ENS-PSL), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris Diderot - Paris 7 (UPD7)-École polytechnique (X)-Centre National d'Études Spatiales [Toulouse] (CNES)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS), Institut de Recherche pour le Développement (IRD)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Muséum national d'Histoire naturelle (MNHN)-Institut Pierre-Simon-Laplace (IPSL (FR_636)), École normale supérieure - Paris (ENS Paris), and Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris Diderot - Paris 7 (UPD7)-École polytechnique (X)-Centre National d'Études Spatiales [Toulouse] (CNES)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-École normale supérieure - Paris (ENS Paris)

Subjects
[SDU.STU.GP]Sciences of the Universe [physics]/Earth Sciences/Geophysics [physics.geo-ph], [PHYS.PHYS.PHYS-GEO-PH]Physics [physics]/Physics [physics]/Geophysics [physics.geo-ph]
Abstract

International audience; The Eastern Mediterranean Sea (EMS) lies in a climatological transition zone, under the influence of both tropical and mid-latitude climate processes. Early Holocene sediment records collected in the EMS bear witnesses for the formation of the most recent sapropel S1, closely associated with distinct minima in the orbital precession cycle and the insolation-driven monsoon maxima. The different scenarios of S1 deposition involve changes in marine productivity, organic matter preservation and circulation changes and are still under debate. Herewith, we focus on combined geochemical and micropaleontological proxies, namely organic biomarkers, organic carbon and nitrogen stable isotopes and coccolithophore assemblages, aiming at reconstructing climate-related parameters such as sea surface temperature (SST), marine productivity patterns, stratification and nutricline fluctuations and continental inputs in three gravity cores collected along a north-south transect in the EMS. Depending on the water column depth, the sediment accumulation rates and the hydrographic circulation patterns, S1 deposited in our records between ~9.8 to 6.4 kyr BP. During the Holocene climatic optimum, SSTs increase gradually more than 4° C and reaches values as high as 21.2° C, 22.5° C and 23° C along the N-S transect. Our records also show a pronounced centennial-scale cooling that culminates at ~ 8.0 kyrs BP, coeval to the N. Atlantic cooling event, causing an interruption in the deposition of S1 in all sites. Moreover, SST fluctuations are detected between 4.9 and 4.1 kyr BP, with a sharp positive shift to 24.9° C indicating the presence of a warm period in the mid Holocene. Higher accumulation rates of TOC, marine biomarkers and coccolithophore assemblages were recorded during the S1a, S1b and Mid Holocene Humid (MHH) phases, indicating higher productivity and/or better preservation of organic matter. Furthermore, distribution patterns, composition and characteristic ratios of marine biomarkers and of coccolithophoride species exhibit variability in paleoproductivity trends, hydrographic dynamics and nutricline levels during the Holocene. The distributions of land plant biomarkers are indicative of variable terrigenous organic matter supply and the concomitant transport of nutrients to surface waters. The different types of δ13Corg excursions associated with stronger fluvial delivery (terrestrial inputs) in the north site, whereas the other two sites received most marine organic matter. Lighter values of δ15N within S1 and MHH phases reflect a significant contribution of N-fixing organisms to the N-cycle, related probably to higher demand for nitrogen due to the established dysoxia in the water column/sediment interface, leading to denitrification and P regeneration.

Published
2012

14. Late postglacial paleoenvironmental change in the northeastern Mediterranean region: Combined palynological and molecular biomarker evidence

Author

Kouli, K. Gogou, A. Bouloubassi, I. Triantaphyllou, M.V. Ioakim, C. Katsouras, G. Roussakis, G. Lykousis, V.

Abstract

Three gravity cores collected from the NE Mediterranean (NEMR) across a transect from the northern Aegean Sea (North Skyros basin) to the south Cretan margin (SCM), were investigated for pollen and terrestrial biomarkers derived from epicuticular waxes of vascular plants during the last ~20 ky. Pollen data show diversified mixed temperate forest in the northern borderlands and enhanced Mediterranean vegetation in the southern areas, documenting an N-S climatic trend. Terrestrial plant biomarkers and their diagnostic geochemical indices exhibit latitudinal patterns which are interpreted in terms of the different delivery pathways (fluvial/runoff vs. atmospheric transport), resulting from the climate conditions during different periods. During the Late Glacial and early deglaciation periods (20-14 ka BP) relatively increased humidity (H-index) is recorded in the north Aegean Sea, while in the South drier climate was the limiting factor for vegetation development. During this interval, terrestrial n-alkanes showed increased accumulation rates, suggesting massive transport of terrestrial organic matter through runoffs and rivers, followed by weaker input after 14 ka BP. After ~11 ka BP a major expansion of forest cover is evidenced in the NEMR, accompanied by a higher H-index because of the climatic amelioration. The forest vegetation exhibited regionally different characteristics, with cool temperate taxa being more abundant in the Aegean cores, while the SCM record is being featured by Mediterranean elements. At the onset of the Holocene and throughout the Holocene Climatic Optimum the delivery of terrestrial biomarkers increased and became more significant in the Aegean sites compared to the SCM site. Within the Holocene, the average chain length (ACL) of long chain n-alkanes exhibits lower values in the northern Aegean than in the southeastern Aegean and SCM, indicating the predominance of warmer species southwards. Finally, the H-index records a conspicuous humidity increase between 5.4 and 4.3 ka BP in the south Aegean that coincides with an increase in the terrestrial biomarker supply and the deposition of a distinct sapropel-like layer, SMH (Sapropel Mid Holocene). Similar trends in T (temperature) and H indices are slightly delayed and attenuated in the northern Aegean and are accompanied by an increase in the ACL index. A noticeable increase in the accumulation rates (ARs) of terrestrial biomarkers and the HPA index values during this period are clearly recorded in all three cores, indicative of enhanced terrigenous inputs of organic matter along with higher in-situ preservation. © 2011.

Published
2012

15. Holocene Centenial-scale Paleoceanographic and Paleoenvironmental Patterns in the NE Mediterranean Sea

Author

Bouloubassi, Ioanna, Gogou, Alexandra, Triantaphyllou, Maria V., Katsouras, G., Kouli, K., Roussakis, Grigoris, Likousis, V., Laboratoire d'Océanographie et du Climat : Expérimentations et Approches Numériques (LOCEAN), Muséum national d'Histoire naturelle (MNHN)-Institut de Recherche pour le Développement (IRD)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Institut Pierre-Simon-Laplace (IPSL (FR_636)), École normale supérieure - Paris (ENS-PSL), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris Diderot - Paris 7 (UPD7)-École polytechnique (X)-Centre National d'Études Spatiales [Toulouse] (CNES)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-École normale supérieure - Paris (ENS-PSL), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris Diderot - Paris 7 (UPD7)-École polytechnique (X)-Centre National d'Études Spatiales [Toulouse] (CNES)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS), Institut de Recherche pour le Développement (IRD)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Muséum national d'Histoire naturelle (MNHN)-Institut Pierre-Simon-Laplace (IPSL (FR_636)), École normale supérieure - Paris (ENS Paris), and Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris Diderot - Paris 7 (UPD7)-École polytechnique (X)-Centre National d'Études Spatiales [Toulouse] (CNES)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-École normale supérieure - Paris (ENS Paris)

Subjects
Abrupt/rapid climate change, Micropaleontology, [4924] PALEOCEANOGRAPHY, Geochemical tracers, [4944] PALEOCEANOGRAPHY, [SDU.STU.GP]Sciences of the Universe [physics]/Earth Sciences/Geophysics [physics.geo-ph], Sea surface temperature, [4954] PALEOCEANOGRAPHY, [PHYS.PHYS.PHYS-GEO-PH]Physics [physics]/Physics [physics]/Geophysics [physics.geo-ph], [4901] PALEOCEANOGRAPHY
Abstract

International audience; The Eastern Mediterranean Sea lies in a climatological transition zone, under the influence of both tropical and mid-latitude climate processes. Within this basin, the Aegean Sea has been recognized as a highly sensitive area to global/regional climate change. Sediment archives provide robust evidence for changes in its hydrological properties and biogeochemical functioning as a response to past climate variability. In order to investigate the region's paleoclimatic and paleoceanographic patterns during the Holocene, with a special emphasis on the sapropel S1 interval, we have investigated marine sediment cores along a N-S transect in the Aegean and the S. Cretan Seas. We focus on combined geochemical, micropaleontological and palynological proxies, namely organic biomarkers, organic carbon and nitrogen stable isotopes, coccolithophore and pollen assemblages, aiming at reconstructing climate-related parameters such as sea surface temperature (SST), marine productivity patterns, stratification and nutricline fluctuations, continental vegetation patterns and land-sea interactions. SST patterns depict major global/regional climate fluctuations during the last glacial and deglaciation periods, depict the warm transition to the Holocene optimum, when the formation of the S1 sapropel takes place, a distinct cool episode around 8 ka BP (coeval with the S1 interruption), a conspicuous mid-Holocene warm phase (5.4-4.3 ka BP) as well as other distinct fluctuations. Diagnostic marine lipids, δ15N, and coccolithophore assemblages allow documenting the variability of primary productivity and associated organic carbon accumulation in sediments, as well as fluctuations in water column stratification and nutricline, especially during the deposition of the S1 sapropel. Combined terrigenous proxies record warm/cool and dry/humid time intervals, allowing land-sea correlations, and document changes in the delivery of terrestrial material to the sea related to climate-driven fluctuations in freshwater discharges. The network of sediment cores studied provide a better constrain of the regional climate patterns in the northeastern Mediterranean Sea and enables assessing potential time lags and gradients.

Published
2011

16. Organic carbon distribution and isotopic composition in three records from the eastern Mediterranean Sea during the Holocene

Author

Katsouras, G. Gogou, A. Bouloubassi, I. Emeis, K.-C. Triantaphyllou, M. Roussakis, G. Lykousis, V.

Abstract

We investigated the distribution of organic carbon (TOC) and bulk organic δ13Corg values in two cores from the Aegean Sea and one from the Libyan Sea, eastern Mediterranean Sea (EMS) with a focus on the timing and regional expression of sapropel S1 deposition in the early Holocene. Our data indicate that the onset of S1 occurred earlier in the Libyan Sea (∼9.8kyr BP) than in the Aegean Sea (∼8.9kyr BP), implying that dysoxia/anoxia started earlier in the deeper sites of the EMS than in the shallower sites in the Aegean Sea. Accumulation rates of organic matter (OM) during the S1 period have a clear decreasing gradient from north to south, with higher values in the Aegean Sea and TOC contents higher in the deep basin. The three sedimentary sequences exhibit δ13Corg values that fall within the range of algal OM (-25‰ to -20‰). Shifts to lighter δ13Corg values within sapropel intervals in the Aegean sites can be interpreted as the result of elevated marine production, enhanced inflow of light terrestrial dissolved inorganic carbon and/or of the shoaling of the pycnocline, along with the presence of a deep chlorophyll maximum (DCM) during the S1 period. © 2010 Elsevier Ltd.

Published
2010

17. A biomarker study of high resolution sedimentary records in the eastern Mediterranean Sea since the last glacial maximum

Author

Katsouras, G., Gogou, A., Bouloubassi, Ioanna, Emeis, K. -C., Triantaphyllou, M. V., Lykousis, V., Laboratoire d'Océanographie et du Climat : Expérimentations et Approches Numériques (LOCEAN), Muséum national d'Histoire naturelle (MNHN)-Institut de Recherche pour le Développement (IRD)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Institut Pierre-Simon-Laplace (IPSL (FR_636)), École normale supérieure - Paris (ENS-PSL), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris Diderot - Paris 7 (UPD7)-École polytechnique (X)-Centre National d'Études Spatiales [Toulouse] (CNES)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-École normale supérieure - Paris (ENS-PSL), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris Diderot - Paris 7 (UPD7)-École polytechnique (X)-Centre National d'Études Spatiales [Toulouse] (CNES)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS), and EGU

Subjects
[SDU]Sciences of the Universe [physics]
Abstract

International audience; Information stored in sedimentary records provides evidence on climate and environmental variability at decadal to centennial time scales. The eastern Mediterranean Sea and the related Aegean Sea exhibit high sedimentation rates in certain areas and are considered as sensitive regions to record paleo-environmental and -climatic changes. The aim of our study is to reconstruct high-frequency paleoclimatic variations and identify associated changes in the physical, chemical and biological environment in selected basins of the eastern Mediterranean Sea, using molecular biogeochemical proxies. Here we present a high-resolution multi-proxy study along two Aegean Sea cores (north (152SL) and southeast (NS-14)) and a Libyan Sea core (HCM2/22). An important time marker and indicator of remarkable climatic and environmental changes is sapropel S1, a sediment layer rich in organic carbon. Depending on the water column depth, the sediment accumulation rates and the proximity to freshwater and water formation sources, S1 deposited between ~9.8 to 6.4 kyr BP, with an apparent interruption in the S1 deposition that occurred from ~8.6 to 7.6 kyr BP. SSTs based on alkenone unsaturation index Uḱ 37, ^15tot, ^13Corg and various marine and terrestrial biomarkers are used to investigate the region's climatic variability, and the modifications in the biogeochemical functioning of the eastern Mediterranean Sea. Uḱ 37 SST distribution in our records reveals significant fluctuations in temperature over the last 20.000 yrs. Organic carbon stable isotopes values span a narrow range over the whole sequence, with values varying to typical marine origin. The distributions of land-plant biomarkers are indicative of variable terrigenous organic matter supply and the concomitant transport of nutrients to surface waters. Furthermore, the distribution patterns and characteristic ratios of marine biomarkers exhibit differences in the paleoproductivity trends and ventilation changes over the last 20 kyr. Low ^15N values within the sapropel layers reflect a significant contribution of N-fixation to the N-cycle, related probably to higher demand for nitrogen due to denitrification and sedimentary phosphorous regeneration processes under low-oxygen conditions.

Published
2009

18. Emiliania huxleyi coccolith d18O during the deposition of sapropel S1 in the Aegean Sea

Author

Triantaphyllou, M. V., Ziveri, P., Lianou, V., Mortyn, P. G., Katsouras, G., Gogou, A., Bouloubassi, Ioanna, Emeis, K. -C., Lykousis, V., Laboratoire d'Océanographie et du Climat : Expérimentations et Approches Numériques (LOCEAN), Muséum national d'Histoire naturelle (MNHN)-Institut de Recherche pour le Développement (IRD)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Institut Pierre-Simon-Laplace (IPSL (FR_636)), École normale supérieure - Paris (ENS-PSL), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris Diderot - Paris 7 (UPD7)-École polytechnique (X)-Centre National d'Études Spatiales [Toulouse] (CNES)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-École normale supérieure - Paris (ENS-PSL), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris Diderot - Paris 7 (UPD7)-École polytechnique (X)-Centre National d'Études Spatiales [Toulouse] (CNES)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS), and EGU

Subjects
[SDU]Sciences of the Universe [physics]
Abstract

International audience; Much interest has been concentrated recently on the Aegean Sea, an eastern Mediterranean basin situated within a climatic transition zone which represents an important source area of new deep water for the entire eastern Mediterranean. Recent paleoceanographic research has shown that the Aegean Sea sediment record, although featuring organic-rich sapropel layers that demonstrated periodically different productivity, circulation and preservation conditions in the past, provides a direct link to the high-latitude Holocene climate influences. This is superimposed on the underlying subtropical/tropical control on the eastern Mediterranean Sea hydrography and ecosystem, suggesting that paloclimatic conditions that accompanied sapropel deposition were not always uniform. This research uses the inorganic and organic chemistry of coccolithophores to monitor changes in sea water chemistry and ecology during the sapropel S1 deposition in the Aegean Sea. In particular d18O on coccoliths of Emiliania huxleyi has been analyzed from a number of samples spanning S1 from the SE Aegean core NS-14 and the North Aegean core 152SL. Age model, marine biogeochemical conditions and SSTs derived from alkenones, are well determined in both cores. The calculated d18Ow variability is related to both changes in freshwater input and carbonate ion concentration. d18Ow decreases (approx. 0.6 o/oo) before S1 deposition, demonstrating fresher conditions and a possible runoff source for nutrient delivery. Here we will present various lines of coccolithophore evidence in support of this conclusion, as well as corroborating planktonic foraminiferal d18O data from the surface-dwelling species, Globigerinoides ruber.

Published
2009

19. Late Glacial-Holocene climate variability at the south-eastern margin of the Aegean Sea

Author

Triantaphyllou, M.V. Ziveri, P. Gogou, A. Marino, G. Lykousis, V. Bouloubassi, I. Emeis, K.-C. Kouli, K. Dimiza, M. Rosell-Melé, A. Papanikolaou, M. Katsouras, G. Nunez, N.

Abstract

New micropaleontological, palynological, and geochemical results from a relatively shallow (∼ 500 m) sediment core (NS-14) in the south-eastern Aegean Sea provide a detailed picture of the regional expression of sapropel S1 formation in this sub-basin of the eastern Mediterranean Sea. Specifically, freshwater input during ∼ 10.6-10.0 ka BP has preceded the deposition of S1. Further decrease in surface water salinity is evidenced between 10.0 and 8.5 ka BP at the lower part of S1a, which in respect to S1b, is featured by warmer (∼ 19.5 °C) and more productive surface waters associated with dysoxic bottom conditions. A series of coolings detected within the S1 depositional interval, may be linked to outbursts of cold northerly air masses and relevant pulses in the deep-intermediate water ventilation that caused the S1 interruption between 7.9 and 7.3 ka BP and culminated during the deposition of S1b, with the decline of deep chlorophyll maximum (DCM) at ∼ 6.5 ka BP. The climate instability and the relevant absence of anoxia weakened the organic matter preservation in the shallow south-eastern Aegean margin during the S1 times. NS-14 record provides evidence for a distinct mid Holocene warm (up to ∼ 25 °C) and wet phase associated with the deposition of the sapropel-like layer SMH (Sapropel Mid Holocene), between 5.4 and 4.3 ka BP. The SMH layer could represent evidence of on-going, albeit weak, African monsoon forcing, only expressed at the south-eastern edge of the Aegean Sea. Its end is associated with the 4.2 ka BP Northern Hemisphere mega-drought event and the termination of the African Humid Period at 3.8 ka BP. © 2009 Elsevier B.V. All rights reserved.

Published
2009

20. Late Glacial-Holocene climate variability at the south-eastern margin of the Aegean Sea

Author

Triantaphyllou, M V, Ziveri, Patrizia, Gogou, A, Marino, Gianluca, Lykousis, V, Bouloubassi, I, Emeis, K-C, Kouli, K, Dimiza, M, Rosell-Mele, A, Papanikolaou, M, Katsouras, G, Nunez, N, Triantaphyllou, M V, Ziveri, Patrizia, Gogou, A, Marino, Gianluca, Lykousis, V, Bouloubassi, I, Emeis, K-C, Kouli, K, Dimiza, M, Rosell-Mele, A, Papanikolaou, M, Katsouras, G, and Nunez, N

Abstract

New micropaleontological, palynological, and geochemical results from a relatively shallow (∼ 500 m) sediment core (NS-14) in the south-eastern Aegean Sea provide a detailed picture of the regional expression of sapropel S1 formation in this sub-basin

Published
2009

21. Is 40 Joules Enough to Successfully Defibrillate With Subcutaneous Implantable Cardioverter-Defibrillators?

Author

Maurizio Eugenio Landolina, Antonio Pangallo, Antonio D'Onofrio, Grigorios Katsouras, Mauro Biffi, Stefano Viani, Gerardo Nigro, Sergio Valsecchi, Mariolina Lovecchio, Matteo Ziacchi, Carlo Lavalle, Michele Manzo, Vincenzo Bonfantino, 'S-Icd Rhythm Detect' Investigators, Paolo Pieragnoli, Igor Diemberger, Maria Grazia Bongiorni, Valter Bianchi, Giovanni Battista Perego, Pietro Palmisano, Luca Ottaviano, Biffi M., Bongiorni M.G., D'Onofrio A., Manzo M., Pieragnoli P., Palmisano P., Ottaviano L., Perego G.B., Pangallo A., Lavalle C., Bonfantino V., Nigro G., Landolina M.E., Katsouras G., Diemberger I., Viani S., Bianchi V., Lovecchio M., Valsecchi S., and Ziacchi M.

Subjects
implantable defibrillator, Male, medicine.medical_specialty, Test failure, Defibrillation, medicine.medical_treatment, 030204 cardiovascular system & hematology, Implantable defibrillator, 03 medical and health sciences, 0302 clinical medicine, Internal medicine, defibrillation test, Humans, Medicine, 030212 general & internal medicine, conversion, Lead (electronics), Male gender, High rate, business.industry, Arrhythmias, Cardiac, subcutaneou, medicine.disease, Defibrillators, Implantable, Shock (circulatory), Ventricular Fibrillation, Ventricular fibrillation, Cardiology, medicine.symptom, business, Human
Abstract

Objectives: This study evaluated the efficacy of conversion test performed at 40 J (defibrillation margin ≥40 J), and factors potentially associated with test failure were identified. Background: Current subcutaneous implantable cardioverter-defibrillator (S-ICD) devices deliver a maximum of 80 J. Functional defibrillation testing is recommended at S-ICD implantation, and it is usually conducted by delivering a shock energy of 65 J to ensure a safety defibrillation margin ≥15 J. Although high rates of successful conversion were reported at 65 J, limited data exist on the defibrillation margin extent. Methods: Ventricular fibrillation was induced and conversion test was performed by delivering a 40-J shock in 308 patients. Success was defined as termination of ventricular fibrillation by the first shock delivered in standard polarity. The S-ICD system positioning was evaluated with the PRAETORIAN score using bidirectional chest X-rays. Results: The generator was positioned in an intermuscular pocket in 301 patients (98%) and the lead was implanted by means of a 2-incision technique. The PRAETORIAN score was 50 (OR: 2.93; 95% CI: 1.26 to 6.83; p = 0.013) were independently associated with conversion failure. Conclusions: The authors showed a high rate of defibrillation success with 40-J shocks in S-ICD systems implanted by means of modern surgical techniques. The variables associated with shock failure were male gender, higher body mass index, and suboptimal device position according to the PRAETORIAN score.

Published
2021

22. Use of Unmanned Surface Vehicles (USVs) in Water Chemistry Studies.

Author

Katsouras G, Dimitriou E, Karavoltsos S, Samios S, Sakellari A, Mentzafou A, Tsalas N, and Scoullos M

Abstract

Unmanned surface vehicles (USVs) equipped with integrated sensors are a tool valuable to several monitoring strategies, offering enhanced temporal and spatial coverage over specific timeframes, allowing for targeted examination of sites or events of interest. The elaboration of environmental monitoring programs has relied so far on periodic spot sampling at specific locations, followed by laboratory analysis, aiming at the evaluation of water quality at a catchment scale. For this purpose, automatic telemetric stations for specific parameters have been installed by the Institute of Marine Biological Resources and Inland Waters of Hellenic Centre for Marine Research (IMBRIW-HCMR) within several Greek rivers and lakes, providing continuous and temporal monitoring possibilities. In the present work, USVs were deployed by the Athens Water and Sewerage Company (EYDAP) as a cost-effective tool for the environmental monitoring of surface water bodies of interest, with emphasis on the spatial fluctuations of chlorophyll α, electrical conductivity, dissolved oxygen and pH, observed in Koumoundourou Lake and the rivers Acheloos, Asopos and Kifissos. The effectiveness of an innovative heavy metal (HM) system installed in the USV for the in situ measurements of copper and lead was also evaluated herewith. The results obtained demonstrate the advantages of USVs, setting the base for their application in real-time monitoring of chemical parameters including metals. Simultaneously, the requirements for accuracy and sensitivity improvement of HM sensors were noted, in order to permit full exploitation of USVs' capacities.

Published
2024
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23. Worldwide survey on implantation of and outcomes for conduction system pacing with His bundle and left bundle branch area pacing leads.

Author

Perino AC, Wang PJ, Lloyd M, Zanon F, Fujiu K, Osman F, Briongos-Figuero S, Sato T, Aksu T, Jastrzebski M, Sideris S, Rao P, Boczar K, Yuan-Ning X, Wu M, Namboodiri N, Garcia R, Kataria V, De Pooter J, Przibille O, Gehi AK, Cano O, Katsouras G, Cai B, Astheimer K, Tanawuttiwat T, Datino T, Rizkallah J, Alasti M, Feld G, Barrio-Lopez MT, Gilmore M, Conti S, Yanagisawa S, Indik JH, Zou J, Saha SA, Rodriguez-Munoz D, Chang KC, Lebedev DS, Leal MA, Haeberlin A, Forno ARJD, Orlov M, Frutos M, Cabanas-Grandio P, Lyne J, Leyva F, Tolosana JM, Ollitrault P, Vergara P, Balla C, Devabhaktuni SR, Forleo G, Letsas KP, Verma A, Moak JP, Shelke AB, Curila K, Cronin EM, Futyma P, Wan EY, Lazzerini PE, Bisbal F, Casella M, Turitto G, Rosenthal L, Bunch TJ, Baszko A, Clementy N, Cha YM, Chen HC, Galand V, Schaller R, Jarman JWE, Harada M, Wei Y, Kusano K, Schmidt C, Hurtado MAA, Naksuk N, Hoshiyama T, Kancharla K, Iida Y, Mizobuchi M, Morin DP, Cay S, Paglino G, Dahme T, Agarwal S, Vijayaraman P, and Sharma PS

Subjects
Humans, Cross-Sectional Studies, Heart Conduction System, Cardiac Conduction System Disease, Electrocardiography, Cardiac Pacing, Artificial, Treatment Outcome, Bundle of His, Bradycardia therapy
Abstract

Background: Adoption and outcomes for conduction system pacing (CSP), which includes His bundle pacing (HBP) or left bundle branch area pacing (LBBAP), in real-world settings are incompletely understood. We sought to describe real-world adoption of CSP lead implantation and subsequent outcomes., Methods: We performed an online cross-sectional survey on the implantation and outcomes associated with CSP, between November 15, 2020, and February 15, 2021. We described survey responses and reported HBP and LBBAP outcomes for bradycardia pacing and cardiac resynchronization CRT indications, separately., Results: The analysis cohort included 140 institutions, located on 5 continents, who contributed data to the worldwide survey on CSP. Of these, 127 institutions (90.7%) reported experience implanting CSP leads. CSP and overall device implantation volumes were reported by 84 institutions. In 2019, the median proportion of device implants with CSP, HBP, and/or LBBAP leads attempted were 4.4% (interquartile range [IQR], 1.9-12.5%; range, 0.4-100%), 3.3% (IQR, 1.3-7.1%; range, 0.2-87.0%), and 2.5% (IQR, 0.5-24.0%; range, 0.1-55.6%), respectively. For bradycardia pacing indications, HBP leads, as compared to LBBAP leads, had higher reported implant threshold (median [IQR]: 1.5 V [1.3-2.0 V] vs 0.8 V [0.6-1.0 V], p = 0.0008) and lower ventricular sensing (median [IQR]: 4.0 mV [3.0-5.0 mV] vs. 10.0 mV [7.0-12.0 mV], p < 0.0001)., Conclusion: In conclusion, CSP lead implantation has been broadly adopted but has yet to become the default approach at most surveyed institutions. As the indications and data for CSP continue to evolve, strategies to educate and promote CSP lead implantation at institutions without CSP lead implantation experience would be necessary., (© 2022. The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature.)

Published
2023
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24. The PhysioVP-AF study, a randomized controlled trial to assess the clinical benefit of physiological ventricular pacing vs. managed ventricular pacing for persistent atrial fibrillation prevention in patients with prolonged atrioventricular conduction: design and rationale.

Author

Pastore G, Bertini M, Bonanno C, Coluccia G, Dell'Era G, De Mattia L, Grieco D, Katsouras G, Maines M, Marcantoni L, Marinaccio L, Paglino G, Palmisano P, Ziacchi M, Zoppo F, and Noventa F

Subjects
Humans, Cardiac Pacing, Artificial adverse effects, Cardiac Pacing, Artificial methods, Prospective Studies, Single-Blind Method, Sick Sinus Syndrome complications, Sick Sinus Syndrome diagnosis, Sick Sinus Syndrome therapy, Atrial Fibrillation complications, Atrial Fibrillation diagnosis, Atrial Fibrillation therapy, Pacemaker, Artificial, Atrioventricular Block
Abstract

Aims: In patients with prolonged atrioventricular (AV) conduction and pacemaker (PM) indication due to sinus node disease (SND) or intermittent AV-block who do not need continuous ventricular pacing (VP), it may be difficult to determine which strategy to adopt. Currently, the standard of care is to minimize unnecessary VP by specific VP avoidance (VPA) algorithms. The superiority of this strategy over standard DDD or DDD rate-responsive (DDD/DDDR) in improving clinical outcomes is controversial, probably owing to the prolongation of the atrialventricular conduction (PR interval) caused by the algorithms. Conduction system pacing (CSP) may offer the most physiological-VP approach, providing appropriate AV conduction and preventing pacing-induced dyssynchrony., Methods and Results: PhysioVP-AF is a prospective, controlled, randomized, single-blind trial designed to determine whether atrial-synchronized conduction system pacing (DDD-CSP) is superior to standard DDD-VPA pacing in terms of 3-year reduction of persistent-AF occurrence. Cardiovascular hospitalization, quality-of-life, and safety will be evaluated. Patients with indication for permanent DDD pacing for SND or intermittent AV-block and prolonged AV conduction (PR interval > 180 ms) will be randomized (1:1 ratio) to DDD-VPA (VPA-algorithms ON, septal/apex position) or to DDD-CSP (His bundle or left bundle branch area pacing, AV-delay setting to control PR interval, VPA-algorithms OFF). Approximately 400 patients will be randomized in 24 months in 13 Italian centres., Conclusion: The PhysioVP-AF study will provide an essential contribution to patient management with prolonged AV conduction and PM indication for sinus nodal disease or paroxysmal 2nd-degree AV-block by determining whether CSP combined with a controlled PR interval is superior to standard management that minimizes unnecessary VP in terms of reducing clinical outcomes., Competing Interests: Conflict of interest: G.D.: fee for lectures and proctorship for conduction system pacing by Biotronik Italia; G.K., Le.M.: fee for proctorship for conduction system pacing by Biotronik and Medtronic Italia; M.Z.: received speaker’s fees from Abbott Medical, Biotronik, and Boston Scientific; F.N.: fees for statistical and methodological consulting from Abbott Medical. All other authors have no conflicts to declare., (© The Author(s) 2023. Published by Oxford University Press on behalf of the European Society of Cardiology.)

Published
2023
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25. Conduction system pacing, a European survey: insights from clinical practice.

Author

Keene D, Anselme F, Burri H, Pérez ÓC, Čurila K, Derndorfer M, Foley P, Gellér L, Glikson M, Huybrechts W, Jastrzebski M, Kaczmarek K, Katsouras G, Lyne J, Verdú PP, Restle C, Richter S, Timmer S, Vernooy K, and Whinnett Z

Subjects
Humans, Stroke Volume physiology, Ventricular Function, Left, Treatment Outcome, Heart Conduction System, Bundle-Branch Block diagnosis, Bundle-Branch Block therapy, Arrhythmias, Cardiac therapy, Cardiac Resynchronization Therapy, Heart Failure diagnosis, Heart Failure therapy
Abstract

Aims: The field of conduction system pacing (CSP) is evolving, and our aim was to obtain a contemporary picture of European CSP practice., Methods and Results: A survey was devised by a European CSP Expert Group and sent electronically to cardiologists utilizing CSP. A total of 284 physicians were invited to contribute of which 171 physicians (60.2%; 85% electrophysiologists) responded. Most (77%) had experience with both His-bundle pacing (HBP) and left bundle branch area pacing (LBBAP). Pacing indications ranked highest for CSP were atrioventricular block (irrespective of left ventricular ejection fraction) and when coronary sinus lead implantation failed. For patients with left bundle branch block (LBBB) and heart failure (HF), conventional biventricular pacing remained first-line treatment. For most indications, operators preferred LBBAP over HBP as a first-line approach. When HBP was attempted as an initial approach, reasons reported for transitioning to utilizing LBBAP were: (i) high threshold (reported as >2 V at 1 ms), (ii) failure to reverse bundle branch block, or (iii) > 30 min attempting to implant at His-bundle sites. Backup right ventricular lead use for HBP was low (median 20%) and predominated in pace-and-ablate scenarios. Twelve-lead electrocardiogram assessment was deemed highly important during follow-up. This, coupled with limitations from current capture management algorithms, limits remote monitoring for CSP patients., Conclusions: This survey provides a snapshot of CSP implementation in Europe. Currently, CSP is predominantly used for bradycardia indications. For HF patients with LBBB, most operators reserve CSP for biventricular implant failures. Left bundle branch area pacing ostensibly has practical advantages over HBP and is therefore preferred by many operators. Practical limitations remain, and large randomized clinical trial data are currently lacking., Competing Interests: Conflict of interest: Medtronic supported the survey project; however, the views and opinions expressed are those of the authors and not Medtronic and therefore no relevant conflicts of interest to report., (© The Author(s) 2023. Published by Oxford University Press on behalf of the European Society of Cardiology.)

Published
2023
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26. Is 40 Joules Enough to Successfully Defibrillate With Subcutaneous Implantable Cardioverter-Defibrillators?

Author

Biffi M, Bongiorni MG, D'Onofrio A, Manzo M, Pieragnoli P, Palmisano P, Ottaviano L, Perego GB, Pangallo A, Lavalle C, Bonfantino V, Nigro G, Landolina ME, Katsouras G, Diemberger I, Viani S, Bianchi V, Lovecchio M, Valsecchi S, and Ziacchi M

Subjects
Arrhythmias, Cardiac, Humans, Male, Ventricular Fibrillation therapy, Defibrillators, Implantable adverse effects
Abstract

Objectives: This study evaluated the efficacy of conversion test performed at 40 J (defibrillation margin ≥40 J), and factors potentially associated with test failure were identified., Background: Current subcutaneous implantable cardioverter-defibrillator (S-ICD) devices deliver a maximum of 80 J. Functional defibrillation testing is recommended at S-ICD implantation, and it is usually conducted by delivering a shock energy of 65 J to ensure a safety defibrillation margin ≥15 J. Although high rates of successful conversion were reported at 65 J, limited data exist on the defibrillation margin extent., Methods: Ventricular fibrillation was induced and conversion test was performed by delivering a 40-J shock in 308 patients. Success was defined as termination of ventricular fibrillation by the first shock delivered in standard polarity. The S-ICD system positioning was evaluated with the PRAETORIAN score using bidirectional chest X-rays., Results: The generator was positioned in an intermuscular pocket in 301 patients (98%) and the lead was implanted by means of a 2-incision technique. The PRAETORIAN score was <90 (low risk of conversion failure) in 293 (95%) patients. Overall, ventricular fibrillation termination occurred in 259 (84%) patients with 40 J. Male gender (odds ratio [OR]: 3.79; 95% confidence interval [CI]: 1.09 to 13.14; p = 0.036), body mass index (OR: 1.09; 95% CI: 1.01 to 1.19; p = 0.036), dilated cardiomyopathy with reduced ejection fraction (OR: 0.42; 95% CI: 0.20 to 0.87; p = 0.019), and PRAETORIAN score >50 (OR: 2.93; 95% CI: 1.26 to 6.83; p = 0.013) were independently associated with conversion failure., Conclusions: The authors showed a high rate of defibrillation success with 40-J shocks in S-ICD systems implanted by means of modern surgical techniques. The variables associated with shock failure were male gender, higher body mass index, and suboptimal device position according to the PRAETORIAN score., Competing Interests: Funding Support And Author Disclosures Ms. Lovecchio and Mr. Valsecchi are employees of Boston Scientific. All other authors have reported that they have no relationships relevant to the contents of this paper to disclose., (Copyright © 2021 American College of Cardiology Foundation. Published by Elsevier Inc. All rights reserved.)

Published
2021
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27. Ablation of atrial fibrillation and esophageal injury: Role of bipolar and unipolar energy using a novel multipolar irrigated ablation catheter.

Author

Di Monaco A, Quadrini F, Katsouras G, Caccavo V, Troisi F, Quatraro F, Cecere G, Langialonga T, and Grimaldi M

Subjects
Atrial Fibrillation surgery, Body Temperature, Esophagoscopy, Esophagus physiology, Female, Humans, Male, Middle Aged, Monitoring, Physiologic, Pulmonary Veins, Catheter Ablation adverse effects, Catheter Ablation instrumentation, Esophagus injuries
Abstract

Background: The circular nMARQ ablation catheter is a useful tool for pulmonary vein isolation (PVI). Some studies reported a high incidence of esophageal lesions by using this catheter., Objective: The primary aim of this study was to compare the effects on the esophageal wall of bipolar and unipolar energy applied by the nMARQ ablation catheter during AF ablation., Methods: Forty patients (mean age 53 ± 8 years; 26 [65%] men) were enrolled to perform PVI for symptomatic atrial fibrillation. Thirty patients underwent PVI with the nMARQ catheter (group 1) and 10 patients with the ThermoCool Surround Flow catheter (group 2). The procedures were performed with the CARTO3 system. All patients received an esophageal temperature probe. In group 1, we delivered unipolar energy on the left posterior wall with power between 15 and 18 W or bipolar energy with power at 15 W. In group 2, unipolar energy was delivered on the posterior atrial wall at 20-25 W power. All patients underwent esophagoscopy the day after the procedure., Results: No patients had procedural complications. In group 1, bipolar energy was associated with a lower esophageal temperature increase as compared with unipolar energy (0.6°C [range 0-2.2°C] vs 2.1°C [range 0.8-2.9°C]; P < .001). Unipolar energy was associated with a similar temperature increase in the 2 groups (1.9°C [range 0.8-2.9°C] in group 1 vs 1.7°C [range 0.7-2.9°C] in group 2; P = .49). No patient had esophageal injury., Conclusion: The use of the nMARQ catheter for PVI is feasible and safe. The use of 15 W for bipolar energy or 15-18 W for unipolar energy is an optimal strategy to avoid esophageal injury with this new catheter., (Copyright © 2015 Heart Rhythm Society. Published by Elsevier Inc. All rights reserved.)

Published
2015
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28. Atrial fibrillation-associated remodeling does not promote atrial thrombus formation in canine models.

Author

Nishida K, Chiba K, Iwasaki YK, Katsouras G, Shi YF, Blostein MD, Khairy P, Guerra PG, Dubuc M, Tardif JC, Tanguay JF, and Nattel S

Subjects
Animals, Antithrombin III, Atrial Fibrillation blood, C-Reactive Protein metabolism, Catheter Ablation, Chronic Disease, Disease Models, Animal, Dogs, Electrocardiography, Heart Failure blood, Heart Failure physiopathology, Peptide Hydrolases blood, Thrombosis blood, Atrial Fibrillation complications, Atrial Fibrillation physiopathology, Thrombosis etiology, Thrombosis physiopathology, Ventricular Remodeling physiology
Abstract

Background: The most important complication of atrial fibrillation (AF) is thromboembolic stroke. Although AF-related remodeling is considered important in atrial thrombogenesis, its role never has been directly tested. This study assessed effects of AF-related remodeling on the atrial thrombogenic milieu by using radiofrequency ablation (RFA) to create a quantifiable prothrombotic nidus., Methods and Results: We studied normal control dogs (control, n=16) and 3 canine AF-models: (1) atrial tachycardia remodeling (ATR; n=16) induced by atrial tachypacing (400 bpm for 1 week, with atrioventricular block and ventricular pacing at 80 bpm); (2) congestive heart failure (CHF; n=14) attributable to ventricular tachypacing (240 bpm for 2 weeks); and (3) chronic AF (CAF; n=8) induced by atrial tachypacing (35±3 days) without atrioventricular block. CAF dogs had AF for 13±1 days until euthanization. After remodeling was established, RFA lesions were created in both atria. Half the ATR and CHF dogs were subjected to atrial tachypacing during 7-day post-RFA follow-up. Electrophysiological and echocardiographic studies were performed before RFA and 7 days after RFA, and then hearts were removed and atrial thrombi were quantified by histomorphometry. Burst-pacing-induced AF duration was significantly greater in ATR, CHF, and CAF groups versus control group. The atrial effective refractory period shortened in ATR and CAF groups. Left atrial diameter was significantly larger with CHF, but not with ATR. Neither total thrombus volume nor thrombus volume per lesion differed significantly among groups. Table.Properties of Ablation Lesions and Atrial Thrombi Experimental GroupControl (n=16)ATR (n=16)CHF (n=14)CAF (n=8)N of ablation lesions per dog6.9±0.36.6±0.27.2±0.26.9±0.4Ablation lesion area, mm(2)53.1±3.558.3±4.857.7±4.944.3±3.7Ablation lesion depth, mm5.2±0.25.1±0.35.3±0.25.2±0.2Ablation lesion volume, mm(3)205.2±17.8211.6±17.6231.5±29.0176.8±22.2N of thrombi per dog5.4±0.44.7±0.35.6±0.46.5±0.4Presence of thrombus, %80±572±577±695±3Mean thrombus volume in both atria, mm(3)20.8±3.414.9±2.212.2±2.622.5±5.6Mean thrombus volume in left atria, mm(3)8.2±1.54.0±0.95.5±1.68.1±3.3Mean thrombus volume in right atria, mm(3)30.1±5.422.7±4.317.9±4.132.8±8.3Total thrombus volume in both atria, mm(3)140.5±21.399.7±16.886.1±17.5131.1±22.7Total thrombus volume in left atria, mm(3)22.8±5.311.8±3.317.0±3.723.3±6.4Total thrombus volume in right atria, mm(3)117.7±21.587.8±17.269.1±16.1107.8±23.3Thrombus volume normalized to ablation lesion area in both atria, mm(3)/mm(2)0.5±0.10.4±0.11.5±1.10.8±0.3Thrombus volume normalized to ablation lesion volume in both atria0.2±0.10.1±0.00.5±0.40.3±0.1 ATR indicates atrial tachycardia remodeling; CAF, chronic atrial fibrillation; and CHF, congestive heart failure. There were no statistically significant differences for any groups vs control group for any of these variables studied., Conclusions: None of the AF substrates tested, including sustained atrial tachycardia/AF itself, enhanced post-RFA atrial thrombus formation. Indices of electrical and structural remodeling did not predict post-RFA thrombogenic potential. Contrary to widely held but previously untested notions, we were unable to demonstrate prothrombotic effects of AF-related remodeling.

Published
2012
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29. Differences in atrial fibrillation properties under vagal nerve stimulation versus atrial tachycardia remodeling.

Author

Katsouras G, Sakabe M, Comtois P, Maguy A, Burstein B, Guerra PG, Talajic M, and Nattel S

Subjects
Animals, Atrial Fibrillation etiology, Dogs, Electrophysiology, Heart Atria physiopathology, Heart Conduction System physiopathology, Refractory Period, Electrophysiological, Tachycardia, Ectopic Atrial complications, Atrial Fibrillation physiopathology, Tachycardia, Ectopic Atrial physiopathology, Vagus Nerve Stimulation
Abstract

Background: There are many similarities between atrial effects of atrial tachycardia remodeling (ATR) and vagal nerve stimulation (VS): both promote atrial fibrillation (AF), reduce atrial effective refractory period (AERP) and AERP rate accommodation, enhance AERP heterogeneity, and increase inward-rectifier K+ current., Objective: This study sought to compare the consequences of ATR and VS at similar levels of AERP abbreviation in dogs., Methods: ATR dogs (n = 6) were subjected to 7-day atrial tachypacing at 400 beats/min, with radiofrequency-induced atrioventricular block and ventricular demand pacing (80 beats/min) to control ventricular response. VS was applied in 6 matched dogs with stimulation parameters selected to produce similar mean AERP values to ATR dogs., Results: ATR and VS produced similarly short AERPs (79 +/- 12 and 80 +/- 12 ms, respectively), AERP rate-adaptation loss, and AERP heterogeneity increases. Although both ATR and VS increased AF duration, VS was significantly more effective in AF promotion, with mean AF duration of 992 +/- 134 seconds, versus 440 +/- 240 seconds (P <.05) under ATR. The greater AF-promoting effect of VS was associated with greater mean dominant frequency values during AF (11.7 +/- 1.8 versus 10.0 +/- 1.3 Hz ATR, P <.05). VS greatly enhanced the spatial dominant frequency variability, increasing the coefficient of variation to 15.2 +/- 1.9 Hz, versus 8.9 +/- 1.5 Hz for ATR (P <.05), primarily by increasing the per-dog maximum dominant frequency (15.4 +/- 0.6 Hz versus 12.5 +/- 0.6 for ATR, P <.01)., Conclusion: For matched AERP values, VS promotes AF more strongly than ATR. Despite similar AERP changes, VS produces considerably greater increases in dominant frequencies, particularly maximum values, consistent with previous suggestions that inward-rectifier K+ current enhancement is particularly effective at accelerating and stabilizing spiral wave rotors that maintain AF.

Published
2009
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30. Transcatheter mapping and ablation of arrhythmias in the coronary sinus.

Author

Katsouras G, Dubuc M, and Khairy P

Subjects
Humans, Veins surgery, Arrhythmias, Cardiac diagnosis, Arrhythmias, Cardiac surgery, Cardiac Catheterization, Catheter Ablation, Coronary Vessels surgery
Abstract

The coronary sinus (CS) is a complex structure of particular interest to cardiac electrophysiologists. It is exploited as an anatomical reference, a site to record left-sided atrial and ventricular signals and for cardiac resynchronization therapy. Perhaps less appreciated, it may itself serve as a substrate for arrhythmias. It is now increasingly recognized that arrhythmias may be targeted by transcatheter ablation within the CS. This review summarizes pertinent anatomic considerations, explores the relationship between the CS and various arrhythmia substrates, elaborates on current indications for intra CS ablation and addresses efficacy and safety concerns associated with transcatheter ablation.

Published
2006
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