Search

Knowledge on the effects of negative pressure wound therapy (NPWT) on the intra-thoracic organs is limited. The present study was performed to investigate the effects of NPWT on the volume of the intra-thoracic organs, using magnetic resonance imaging (MRI), in a porcine sternotomy wound model. Six pigs underwent median sternotomy followed by NPWT at -75, -125 and -175 mmHg. Six pigs were not sternotomised. MR images covering the thorax and heart were acquired. The volumes of the thoracic cavity, lungs, wound fluid and heart were then determined. The volumes of the thoracic cavity and intra-thoracic organs increased after sternotomy and decreased upon NPWT application. The total heart volume variation, which is a measure of cardiac pumping efficiency, was higher after sternotomy and decreased during NPWT. NPWT did not result in the evacuation of wound fluid from the bottom of the wound. NPWT largely closes and restores the thoracic cavity. Cardiac pumping efficiency returns to pre-sternotomy levels during NPWT. This may contribute to the clinical benefits of NPWT over open-chest care, including the stabilizing effects and the reduced need for mechanical ventilation. [ABSTRACT FROM AUTHOR]

Background: Polymorphonuclear neutrophils, stimulated by the activated complement factor C5a, have been implicated in cardiac ischemia/reperfusion injury. ADC-1004 is a competitive C5a receptor antagonist that has been shown to inhibit complement related neutrophil activation. ADC-1004 shields the neutrophils from C5a activation before they enter the reperfused area, which could be a mechanistic advantage compared to previous C5a directed reperfusion therapies. We investigated if treatment with ADC-1004, according to a clinically applicable protocol, would reduce infarct size and microvascular obstruction in a large animal myocardial infarct model.Methods: In anesthetized pigs (42-53 kg), a percutaneous coronary intervention balloon was inflated in the left anterior descending artery for 40 minutes, followed by 4 hours of reperfusion. Twenty minutes after balloon inflation the pigs were randomized to an intravenous bolus administration of ADC-1004 (175 mg, n = 8) or saline (9 mg/ml, n = 8). Area at risk (AAR) was evaluated by ex vivo SPECT. Infarct size and microvascular obstruction were evaluated by ex vivo MRI. The observers were blinded to the treatment at randomization and analysis.Results: ADC-1004 treatment reduced infarct size by 21% (ADC-1004: 58.3 ± 3.4 vs control: 74.1 ± 2.9%AAR, p = 0.007). Microvascular obstruction was similar between the groups (ADC-1004: 2.2 ± 1.2 vs control: 5.3 ± 2.5%AAR, p = 0.23). The mean plasma concentration of ADC-1004 was 83 ± 8 nM at sacrifice. There were no significant differences between the groups with respect to heart rate, mean arterial pressure, cardiac output and blood-gas data.Conclusions: ADC-1004 treatment reduces myocardial ischemia-reperfusion injury and represents a novel treatment strategy of myocardial infarct with potential clinical applicability. [ABSTRACT FROM AUTHOR]

Background: In the setting of primary percutaneous coronary intervention, patients with a chronic total occlusion in a non-infarct related artery were recently identified as a high-risk subgroup. It is unclear whether ST-elevation myocardial infarction patients with a chronic total occlusion in a non-infarct related artery should undergo additional percutaneous coronary intervention of the chronic total occlusion on top of optimal medical therapy shortly after primary percutaneous coronary intervention. Possible beneficial effects include reduction in adverse left ventricular remodeling and preservation of global left ventricular function and improved clinical outcome during future coronary events.Methods/design: The Evaluating Xience V and left ventricular function in Percutaneous coronary intervention on occLusiOns afteR ST-Elevation myocardial infarction (EXPLORE) trial is a randomized, prospective, multicenter, two-arm trial with blinded evaluation of endpoints. Three hundred patients after primary percutaneous coronary intervention for ST-elevation myocardial infarction with a chronic total occlusion in a non-infarct related artery are randomized to either elective percutaneous coronary intervention of the chronic total occlusion within seven days or standard medical treatment. When assigned to the invasive arm, an everolimus-eluting coronary stent is used. Primary endpoints are left ventricular ejection fraction and left ventricular end-diastolic volume assessed by cardiac Magnetic Resonance Imaging at four months. Clinical follow-up will continue until five years.Discussion: The ongoing EXPLORE trial is the first randomized clinical trial powered to investigate whether recanalization of a chronic total occlusion in a non-infarct related artery after primary percutaneous coronary intervention for ST-elevation myocardial infarction results in a better preserved residual left ventricular ejection fraction, reduced end-diastolic volume and enhanced clinical outcome.Trial Registration: trialregister.nl NTR1108. [ABSTRACT FROM AUTHOR]

Background: The aim of this study was to evaluate the combination of a rapid intravenous infusion of cold saline and endovascular hypothermia in a closed chest pig infarct model.Methods: Pigs were randomized to pre-reperfusion hypothermia (n = 7), post-reperfusion hypothermia (n = 7) or normothermia (n = 5). A percutaneous coronary intervention balloon was inflated in the left anterior descending artery for 40 min. Hypothermia was started after 25 min of ischemia or immediately after reperfusion by infusion of 1000 ml of 4 degrees C saline and endovascular hypothermia. Area at risk was evaluated by in vivo SPECT. Infarct size was evaluated by ex vivo MRI.Results: Pre-reperfusion hypothermia reduced infarct size/area at risk by 43% (46 +/- 8%) compared to post-reperfusion hypothermia (80 +/- 6%, p < 0.05) and by 39% compared to normothermia (75 +/- 5%, p < 0.05). Pre-reperfusion hypothermia infarctions were patchier in appearance with scattered islands of viable myocardium. Pre-reperfusion hypothermia abolished (0%, p < 0.001), and post-reperfusion hypothermia significantly reduced microvascular obstruction (10.3 +/- 5%; p < 0.05), compared to normothermia: (30.2 +/- 5%).Conclusion: Rapid hypothermia with cold saline and endovascular cooling before reperfusion reduces myocardial infarct size and microvascular obstruction. A novel finding is that hypothermia at the onset of reperfusion reduces microvascular obstruction without reducing myocardial infarct size. Intravenous administration of cold saline combined with endovascular hypothermia provides a method for a rapid induction of hypothermia suggesting a potential clinical application. [ABSTRACT FROM AUTHOR]

Background: Current evidence suggests that use of intracoronary imaging during percutaneous coronary intervention (PCI) of the left main coronary artery (LMCA) reduces mortality. However, there is a scarcity of data on the overall role of intracoronary imaging, particularly in other non-LMCA proximal coronary artery lesions. We aimed to investigate the association of use of intracoronary imaging on outcome in proximal lesions treated with PCI., Methods: The Swedish Coronary Angiography and Angioplasty Registry was used to identify all proximal coronary artery lesions treated with stent implantation between June 11, 2013, and January 16, 2021. Proximal coronary artery lesions (LMCA, proximal left anterior descending artery, left circumflex artery, and right coronary artery) assessed by intracoronary imaging before and/or after stent implantation were matched to control lesions treated based on angiography alone using propensity score matching. The primary end point was target lesion revascularization with PCI, and secondary end points included all-cause mortality and definite stent thrombosis within 3 years., Results: Among the 3623 matched pairs, intracoronary imaging was associated with significantly lower risk of target lesion revascularization, 3.7% vs 4.7%; hazard ratio (HR), 0.77; 95% CI, 0.61-0.97; P = .025, and all-cause mortality, 9.1% vs 12.8%; HR, 0.70; 95% CI, 0.61-0.81; P < .001, with no difference in definite stent thrombosis., Conclusions: The use of intracoronary imaging in proximal coronary artery lesions is associated with lower rates of repeat revascularization and better survival. The results appear to be primarily driven by improved outcome of LMCA lesions. These results reinforce the role of intracoronary imaging in assessing and treating proximal coronary lesions., Competing Interests: The author(s) declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article., (© 2023 The Authors.)

Background The long-term course of coronary atherosclerosis has not been studied in large nationwide cohorts. Understanding the natural history of coronary atherosclerosis could help identify patients at risk for future coronary events. Methods and Results All coronary artery segments with <50% luminal stenosis in patients with a first-time coronary angiogram between 1989 and 2017 were identified (n=2 661 245 coronary artery segments in 248 736 patients) and followed until a clinically indicated angiography within 15 years was performed or until death or end of follow-up (April 2018) using SCAAR (Swedish Coronary Angiography and Angioplasty Registry). The stenosis progression and incidence rates were 2.6% and 1.45 (95% CI, 1.43-1.46) per 1000 segment-years, respectively. The greatest progression rate occurred in the proximal and middle segments of the left anterior descending artery. Male sex and diabetes were associated with a 2-fold increase in risk, and nearly 70% of new stenoses occurred in patients with baseline single-vessel disease (hazard ratio, 3.86 [95% CI, 3.69-4.04]). Coronary artery segments in patients with no baseline risk factors had a progression rate of 0.6% and incidence rate of 0.36 (95% CI, 0.34-0.39), increasing to 8.1% and 4.01 (95% CI, 3.89-4.14) per 1000 segment-years, respectively, in patients with ≥4 risk factors. The prognostic impact of risk factors on stenosis progression was greatest in younger patients and women. Conclusions Coronary atherosclerosis progressed slowly but more frequently in the left coronary artery in men and in the presence of traditional risk factors. Coronary artery segments in patients without risk factors had little or no risk of stenosis progression, and the relative impact of risk factors appears to be of greater importance in younger patients and women. These findings help in the understanding the long-term course of coronary atherosclerosis.

Background: Unfractionated heparin (UFH) is frequently administered before percutaneous coronary intervention (PCI) in patients with ST-segment elevation myocardial infarction (STEMI)., Aims: The aim of the study was to investigate if pretreatment with UFH prior to arrival at the catheterisation laboratory affects coronary artery occlusion, mortality, and in-hospital major bleeding in patients with STEMI undergoing PCI., Methods: Patients with a first STEMI event undergoing PCI between 2008 and 2016 were extracted from the Swedish Coronary Angiography and Angioplasty Registry. Risk ratios for UFH pretreatment versus no pretreatment regarding coronary artery occlusion at presentation in the catheterisation laboratory, 30-day mortality, and bleeding were obtained using adjusted Poisson regression models with robust standard errors. Analyses of propensity score (PS)-matched groups were performed to obtain absolute risk differences., Results: In all, 41,631 patients were included, 16,026 (38%) with and 25,605 (62%) without UFH pretreatment. Adjusted risk ratios were 0.89 (95% confidence interval [CI]: 0.87 to 0.90) for coronary artery occlusion, 0.87 (0.77 to 0.99) for mortality, and 1.01 (0.86 to 1.18) for bleeding. In the PS-matched analyses, the absolute risk differences were -0.087 (-0.074 to -0.099) for coronary artery occlusion, -0.011 (-0.017 to -0.0041) for mortality, and 0 (-0.0052 to 0.0052) for bleeding., Conclusions: Pretreatment with UFH was associated with a reduction in coronary artery occlusion among patients with STEMI, with a number needed to treat (NNT) of 12, without increasing the risk of major in-hospital bleeding. Regarding mortality, a reduction was found with UFH pretreatment, with an NNT of 94, but this effect was not robust over all sensitivity analyses and residual confounding cannot be excluded.

Background The use of percutaneous coronary intervention (PCI) to treat unprotected left main coronary artery disease has expanded rapidly in the past decade. We aimed to describe nationwide trends in clinical practice and outcomes after PCI for left main coronary artery disease. Methods and Results Patients (n=4085) enrolled in the SCAAR (Swedish Coronary Angiography and Angioplasty Registry) as undergoing PCI for left main coronary artery disease from 2005 to 2017 were included. A count regression model was used to analyze time-related differences in procedural characteristics. The 3-year major adverse cardiovascular and cerebrovascular event rate defined as death, myocardial infarction, stroke, and repeat revascularization was calculated with the Kaplan-Meier estimator and Cox proportional hazard model. The number of annual PCI procedures grew from 121 in 2005 to 589 in 2017 (389%). The increase was greater for men (479%) and individuals with diabetes (500%). Periprocedural complications occurred in 7.9%, decreasing from 10% to 6% during the study period. A major adverse cardiovascular and cerebrovascular event occurred in 35.7% of patients, falling from 45.6% to 23.9% (hazard ratio, 0.56; 95% CI, 0.41-0.78; P =0.001). Radial artery access rose from 21.5% to 74.2% and intracoronary diagnostic procedures from 14.0% to 53.3%. Use of bare-metal stents and first-generation drug-eluting stents fell from 19.0% and 71.9%, respectively, to 0, with use of new-generation drug-eluting stents increasing to 95.2%. Conclusions Recent changes in clinical practice relating to PCI for left main coronary artery disease are characterized by a 4-fold rise in procedures conducted, increased use of evidence-based adjunctive treatment strategies, intracoronary diagnostics, newer stents, and more favorable outcomes.

The authors developed a global chronic total occlusion crossing algorithm following 10 steps: 1) dual angiography; 2) careful angiographic review focusing on proximal cap morphology, occlusion segment, distal vessel quality, and collateral circulation; 3) approaching proximal cap ambiguity using intravascular ultrasound, retrograde, and move-the-cap techniques; 4) approaching poor distal vessel quality using the retrograde approach and bifurcation at the distal cap by use of a dual-lumen catheter and intravascular ultrasound; 5) feasibility of retrograde crossing through grafts and septal and epicardial collateral vessels; 6) antegrade wiring strategies; 7) retrograde approach; 8) changing strategy when failing to achieve progress; 9) considering performing an investment procedure if crossing attempts fail; and 10) stopping when reaching high radiation or contrast dose or in case of long procedural time, occurrence of a serious complication, operator and patient fatigue, or lack of expertise or equipment. This algorithm can improve outcomes and expand discussion, research, and collaboration., Competing Interests: Funding Support and Author Disclosures Dr Wu has received research funding from Abiomed, OrbusNeich, Asahi Intecc; has received consulting honoraria from Boston Scientific and Abbott Vascular; is a member of the board of directors for APCTO Club; and holds stock in Abbott Vascular. Dr Brilakis has received consulting and speaker honoraria from Abbott Vascular, the American Heart Association (associate editor, Circulation), Amgen, Biotronik, Boston Scientific, Cardiovascular Innovations Foundation (board of directors), ControlRad, CSI, Ebix, Elsevier, GE Healthcare, InfraRedx, Medtronic, Siemens, and Teleflex; has received research support from Regeneron and Siemens; is an owner of Hippocrates; and is a shareholder in MHI Ventures. Dr Mashayekhi has received consulting, speaker, and proctoring honoraria from Abbott Vascular, Asahi Intecc, AstraZeneca, Biotronik, Boston Scientific, Cardinal Health, Daiichi-Sankyo, Medtronic, Teleflex, and Terumo. Dr Tsuchikane is a consultant for Boston Scientific, Asahi Intecc, Nipro, and Kaneka. Dr Avran has received consulting, speaker, and proctoring honoraria from Asahi Intecc, Biotronik, Boston Scientific, Terumo, Alvimedica, and OrbusNeich. Dr Azzalini has received consulting fees from Abiomed and Teleflex. Dr Buller is global medical director of Teleflex. Dr Burke is a shareholder in Egg Medical and MHI Ventures. Dr Croce has received grants from Abbott, Takeda, Teleflex, and CSI; has received consulting honoraria from Abbott, BSCI, Biotronik, Philips, Abiomed, CSI, Takeda, and Cordis; and holds stock in Dyad Medical. Dr Damas de los Santos is a proctor, speaker, and consultant for Boston Scientific, Terumo, Abbott Vascular, and Biotronik. Dr Dens has consultancy contracts with Abbott, Boston Scientific, IMDS, Terumo, Topmedical (a distributor for Asahi); and is a chronic total occlusion proctor for Boston Scientific and Topmedical (Asahi). Dr di Mario has received research grants from Abbott, Amgen, Behring, Daiichi-Sankyo, Edwards, Medtronic, and Shockwave Medical. Dr Egred has received chronic total occlusion proctorship fees, speaker fees, honoraria, and grants from Abbott Vascular, Boston Scientific, Philips, Spectranetics, Vascular Perspectives, Merrill, Biotronik, and AstraZeneca. Dr Elbarouni has received speaker fees from Teleflex and Bayer. Dr ElGuindy has received consulting, speaker, and proctoring honoraria from Medtronic, Boston Scientific, Asahi Intecc, and Terumo. Dr Escaned has received personal fees from Abbott, Boston Scientific, Terumo, and Phillips. Dr Furkalo has a proctoring agreement with Medtronic; and has received speaker honoraria from Sanofi. Dr Garbo is a proctor and consultant for Philips Volcano, Boston Europe, Terumo Italy, and Europe Teleflex. Dr Hall has received speaker honoraria from Medtronic, OpSens Medical, and the Cardiovascular Innovations Foundation. Dr Hanna Quesada has received honoraria from Boston Scientific. Dr Harb is a consultant for Medtronic and Cardinal Health; and has received speaker honoraria from Cardinal Health and Terumo. Dr Harding has received speaker and consultancy fees from Boston Scientific, Medtronic, Bio-Excel, and Asahi Intecc. Dr Hatem is a member of the Speakers Bureau for Abbott, Boston Scientific, and Teleflex. Dr Hoye has received speaker fees from AstraZeneca and Sanofi. Dr Jaber has received proctoring fees from Abbott; and has received consulting, advisory board, and institutional funds from Medtronic. Dr Jaffer conducts sponsored research for Canon, Siemens, Teleflex, and Shockwave; is a consultant for Boston Scientific, Siemens, Biotronik, and Magenta Medical; and holds equity interest in Intravascular Imaging. Dr Jussila has a proctoring contract with Boston Scientific and EPS Vascular. Dr Kalyanasundaram has received fees from Abbott Vascular, Boston Scientific, Asahi Intecc, and Terumo. Dr Kandzari has received institutional research grant support from Abbott, Biotronik, Boston Scientific, Cardiovascular Systems, Medtronic, Teleflex, and OrbusNeich; Dr Karmpaliotis has received honoraria from Abbott Vascular and Boston Scientific; and holds equity in Saranas, Soundbite, and Traverse Vascular. Dr Kassem has received speaker honoraria from Boston Scientific, Abbott Vascular, GE, and Abiomed. Dr Khatri has received institutional research grant from Asahi Intecc and honoraria or consulting fees from Abbott Vascular, Boston Scientific, and Terumo. Dr Kornowski is a founder of NitiLoop. Dr Lamelas has received proctoring fees from Boston Scientific, Edwards Lifesciences, and Medtronic. Dr Lim has received educational support and honoraria from Asahi Intecc, Boston Scientific, Abbott Vascular, Kaneka, Biotronik, Alvimedica, Terumo, and Medtronic. Dr Lo has received speaker and proctoring honoraria from Bio-Excel, Boston Scientific, Abbott, and Terumo; and is a member of Medtronic’s advisory board. Dr Lombardi has received royalties and is a consultant for Asahi Intecc; is a consultant for Abiomed, Boston Scientific, Medtronic, Siemens, and Teleflex; and his spouse is an employee of Philips. Dr Maran is a consultant for Boston Scientific, Medtronic, and Philips. Dr Moses has received funding from Orchestra Biomedical and Ostial Corporation. Dr Munawar has received speaker and proctorship honoraria from Asahi Intecc, Terumo, Boston Scientific, Abbott Vascular, Toray, and Phillips. Dr Oksnes has proctoring contracts with Boston Scientific and EPS Vascular. Dr Olivecrona has received lecture honoraria from Abbott and Biotronik; and has received proctoring honoraria from EPS Vascular and Terumo. Dr Patel is a consultant for Abbott Vascular, Terumo, and Chiesi; and is a proctor for Medtronic. Dr Quadros has received honoraria from Boston Scientific; and has received research funding from Boston and Terumo. Dr Abi Rafeh is a proctor and consultant for Boston Scientific, Abbott, and Shockwave Medical. Dr Råmunddal has received consulting honoraria from EPS Vascular, Boston Scientific, and Abbott Vascular. Dr Riley is an advisory board and Speakers Bureau member for and has received consulting honoraria from Boston Scientific, Asahi Intecc, and Medtronic. Dr Saghatelyan has received proctoring and speaker honoraria from Asahi Intecc and Terumo. Dr Spaedy is a consultant for Boston Scientific and Abbott Vascular. Dr Stone has received speaker or other honoraria from Cook and Terumo; is a consultant to Valfix, TherOx, Vascular Dynamics, Robocath, HeartFlow, Gore, Ablative Solutions, Miracor, Neovasc, V-Wave, Abiomed, Ancora, MAIA Pharmaceuticals, Vectorious, Reva, Matrizyme, Cardiomech, Elucid Bio, and Occlutech; and holds equity or options with Ancora, Cagent, Applied Therapeutics, the Biostar family of funds, SpectraWave, Orchestra Biomed, Aria, Cardiac Success, the MedFocus family of funds, and Valfix. Dr Tammam has a proctorship agreement with Terumo. Dr Tremmel has received honoraria from Abbott Vascular and Boston Scientific. Dr Wollmuth has received consulting, speaker, and proctoring honoraria from Abbott Vascular, Abiomed, Asahi Intecc, Biotronik, Boston Scientific, Cardiovascular Systems, Medtronic, and Philips. Dr Ybarra has received consulting and speaker fees from Abbott Vascular Canada and SoundBite Medical Solutions. Dr Yeh has received research grants from Abbott Vascular, AstraZeneca, Cook, BD Bard, Boston Scientific, Medtronic, and Philips; and is a consultant for Abbott Vascular, AstraZeneca, Boston Scientific, Edwards Lifesciences, Medtronic, Shockwave Medical, and Zoll. All other authors have reported that they have no relationships relevant to the contents of this paper to disclose., (Copyright © 2021 The Authors. Published by Elsevier Inc. All rights reserved.)

Aims: Randomized clinical trials have consistently demonstrated the non-inferiority of bioabsorbable polymer drug-eluting stents (BP-DES) with respect to DES having permanent polymers (PP-DES). To date, the comparative performance of BP- and PP-DES in the real world has not been extensively investigated., Methods and Results: From October 2011 to June 2016, we analysed the outcomes associated with newer generation DES use in Sweden. After stratification according to the type of DES received at the index procedure, a total of 16 504 and 79 106 stents were included in the BP- and PP-DES groups, respectively. The Kaplan-Meier estimates for restenosis at 2 years were 1.2% and 1.4% in BP- and PP-DES groups, respectively. Definite stent thrombosis (ST) was low in both groups (0.5% and 0.7% in BP- and PP-DES groups, respectively). The adjusted hazard ratio (HR) for either restenosis or definite ST did not differ between BP- and PP-DES [adjusted HR 0.95, 95% confidence interval (CI) 0.74-1.21; P = 0.670 and adjusted HR 0.79, 95% CI 0.57-1.09; P = 0.151, respectively]. Similarly, there were no differences in the adjusted risk of all-cause death and myocardial infarction (MI) between the two groups (adjusted HR for all-cause death 1.01, 95% CI 0.82-1.25; P = 0.918 and adjusted HR for MI 1.05, 95% CI 0.93-1.19; P = 0.404)., Conclusion: In a large, nationwide, and unselected cohort of patients, percutaneous coronary intervention with BP-DES implantation was not associated with an incremental clinical benefit over PP-DES use at 2 years follow-up., (Published on behalf of the European Society of Cardiology. All rights reserved. © The Author(s) 2019. For permissions, please email: journals.permissions@oup.com.)

Aims: Preliminary studies suggest that direct stenting (DS) during percutaneous coronary intervention (PCI) may reduce microvascular obstruction and improve clinical outcome. Thrombus aspiration may facilitate DS. We assessed the impact of DS on clinical outcome and myocardial reperfusion and its interaction with thrombus aspiration among ST-segment elevation myocardial infarction (STEMI) patients undergoing PCI., Methods and Results: Patient-level data from the three largest randomized trials on routine manual thrombus aspiration vs. PCI only were merged. A 1:1 propensity matched population was created to compare DS and conventional stenting. Synergy between DS and thrombus aspiration was assessed with interaction P-values in the final models. In the unmatched population (n = 17 329), 32% underwent DS and 68% underwent conventional stenting. Direct stenting rates were higher in patients randomized to thrombus aspiration as compared with PCI only (41% vs. 22%; P < 0.001). Patients undergoing DS required less contrast (162 mL vs. 172 mL; P < 0.001) and had shorter fluoroscopy time (11.1 min vs. 13.3 min; P < 0.001). After propensity matching (n = 10 944), no significant differences were seen between DS and conventional stenting with respect to 30-day cardiovascular death [1.7% vs. 1.9%; hazard ratio 0.88, 95% confidence interval (CI) 0.55-1.41; P = 0.60; Pinteraction = 0.96) and 30-day stroke or transient ischaemic attack (0.6% vs. 0.4%; odds ratio 1.02; 95% CI 0.14-7.54; P = 0.99; Pinteraction = 0.81). One-year results were similar. No significant differences were seen in electrocardiographic and angiographic myocardial reperfusion measures., Conclusion: Direct stenting rates were higher in patients randomized to thrombus aspiration. Clinical outcomes and myocardial reperfusion measures did not differ significantly between DS and conventional stenting and there was no interaction with thrombus aspiration.

Background: Thrombus aspiration during percutaneous coronary intervention (PCI) for the treatment of ST-segment-elevation myocardial infarction (STEMI) has been widely used; however, recent trials have questioned its value and safety. In this meta-analysis, we, the trial investigators, aimed to pool the individual patient data from these trials to determine the benefits and risks of thrombus aspiration during PCI in patients with ST-segment-elevation myocardial infarction., Methods: Included were large (n≥1000), randomized, controlled trials comparing manual thrombectomy and PCI alone in patients with ST-segment-elevation myocardial infarction. Individual patient data were provided by the leadership of each trial. The prespecified primary efficacy outcome was cardiovascular mortality within 30 days, and the primary safety outcome was stroke or transient ischemic attack within 30 days., Results: The 3 eligible randomized trials (TAPAS [Thrombus Aspiration During Percutaneous Coronary Intervention in Acute Myocardial Infarction], TASTE [Thrombus Aspiration in ST-Elevation Myocardial Infarction in Scandinavia], and TOTAL [Trial of Routine Aspiration Thrombectomy With PCI Versus PCI Alone in Patients With STEMI]) enrolled 19 047 patients, of whom 18 306 underwent PCI and were included in the primary analysis. Cardiovascular death at 30 days occurred in 221 of 9155 patients (2.4%) randomized to thrombus aspiration and 262 of 9151 (2.9%) randomized to PCI alone (hazard ratio, 0.84; 95% confidence interval, 0.70-1.01; P=0.06). Stroke or transient ischemic attack occurred in 66 (0.8%) randomized to thrombus aspiration and 46 (0.5%) randomized to PCI alone (odds ratio, 1.43; 95% confidence interval, 0.98-2.10; P=0.06). There were no significant differences in recurrent myocardial infarction, stent thrombosis, heart failure, or target vessel revascularization. In the subgroup with high thrombus burden (TIMI [Thrombolysis in Myocardial Infarction] thrombus grade ≥3), thrombus aspiration was associated with fewer cardiovascular deaths (170 [2.5%] versus 205 [3.1%]; hazard ratio, 0.80; 95% confidence interval, 0.65-0.98; P=0.03) and with more strokes or transient ischemic attacks (55 [0.9%] versus 34 [0.5%]; odds ratio, 1.56; 95% confidence interval, 1.02-2.42, P=0.04). However, the interaction P values were 0.32 and 0.34, respectively., Conclusions: Routine thrombus aspiration during PCI for ST-segment-elevation myocardial infarction did not improve clinical outcomes. In the high thrombus burden group, the trends toward reduced cardiovascular death and increased stroke or transient ischemic attack provide a rationale for future trials of improved thrombus aspiration technologies in this high-risk subgroup., Clinical Trial Registration: URLs: http://www.ClinicalTrials.gov http://www.crd.york.ac.uk/prospero/. Unique identifiers: NCT02552407 and CRD42015025936., (© 2016 American Heart Association, Inc.)

Background: Routine thrombus aspiration during primary percutaneous coronary intervention (PCI) in ST-elevation myocardial infarction (STEMI) did not reduce the primary composite endpoint in the "A Randomised Trial of Routine Aspiration ThrOmbecTomy With PCI Versus PCI ALone in Patients With STEMI Undergoing Primary PCI" (TOTAL) trial. We aimed to analyse a similar endpoint in "The Thrombus Aspiration in ST-Elevation myocardial infarction in Scandinavia" (TASTE) trial up to 180 days., Methods: In TASTE, 7244 patients with STEMI were randomised to thrombus aspiration followed by PCI or to PCI alone. We analysed the quadruple composite endpoint of cardiovascular death, cardiogenic shock, rehospitalisation for myocardial infarction, or new hospitalisation for heart failure. Furthermore, an extended net-benefit composite endpoint including stent thrombosis, target vessel revascularization or stroke within 180 days was analysed., Results: The primary quadruple composite endpoint occurred in 8.7 % (316 of 3621) in the thrombus aspiration group compared to 9.3 % (338 of 3623) in the PCI alone group (hazard ratio (HR), 0.93; 95 % confidence interval (CI); 0.80 - 1.09, P = 0.36) and the extended net-benefit composite endpoint in 12.0 % (436) vs. 13.2 % (479) (HR, 0.90; 95 % CI; 0.79 - 1.03, P = 0.12). Stroke within 30 days occurred in 0.7 % (27) vs. 0.7 % (24) (HR, 0.89; 95 % CI; 0.51-1.54, P = 0.68)., Conclusions: A large and an extended composite endpoint analysis from the TASTE trial did not demonstrate any clinical benefit of routine thrombus aspiration during PCI in patients with STEMI. There was no evidence of an increased risk of stroke with thrombus aspiration.

Background: Resuscitation after cardiac arrest (CA) in the catheterization laboratory (cath-lab) using mechanical chest compressions (CC) during simultaneous percutaneous coronary intervention (PCI) is a strong recommendation in the 2015 European Resuscitation Council (ERC) guidelines. This study aimed at re-evaluating survival to hospital discharge and assess long term outcome in this patient population., Methods: Patients presenting at the cath lab with spontaneous circulation, suffering CA and requiring prolonged mechanical CC during cath lab procedures between 2009 and 2013 were included. Circumstances leading to CA, resuscitation parameters and outcomes were evaluated within this cohort. For comparison, patients needing prolonged manual CC in the cath lab in the pre-mechanical CC era were evaluated. Six-month and one year survival with a mechanical CC treatment strategy from 2004 to 2013 was also evaluated., Results: Thirty-two patients were included between 2009 and 2013 (24 ST-elevation myocardial infarction (STEMI), 4 non-STEMI, 2 planned PCI, 1 angiogram and 1 intra-aortic counter pulsation balloon pump insertion). Twenty were in cardiogenic shock prior to inclusion. Twenty-five were successfully treated with PCI. Median mechanical CC duration for the total cohort (n = 32) was 34 min (range 5-90), for the 15 patients with circulation discharged from the cath-lab, 15 min (range 5-90), and for the eight discharged alive from hospital, 10 min (range 5-52). Twenty-five percent survived with good neurological outcome at hospital discharge. Ten patients treated with manual CC were included with one survivor., Discussion: Eighty-seven percent of the patients included in the mechanical CC cohort had their coronary or cardiac intervention performed during mechanical CC with an 80 % success rate. This shows that the use of mechanical CC during an intervention does not seem to impair the interventional result substantially. The survival rate after one year was 87 %., Conclusions: Among patients suffering CA treated with mechanical CC in the cath-lab, 25% had a good neurological outcome at hospital discharge compared to 10% treated with manual CC. Long term survival in patients discharged from hospital is good.

Background: In current guidelines, prolonged cardiopulmonary resuscitation (CPR) mandates administration of repeated intravenous epinephrine (EPI) doses. This porcine study simulating a prolonged CPR-situation in the coronary catheterisation laboratory, explores the effect of EPI-administrations on coronary perfusion pressure (CPP), continuous coronary artery flow average peak velocity (APV) and amplitude spectrum area (AMSA)., Methods: Thirty-six pigs were randomized 1:1:1 to EPI 0.02 mg/kg/dose, EPI 0.03 mg/kg/dose or saline (control) in an experimental cardiac arrest (CA) model. During 15 minutes of mechanical chest compressions, four EPI/saline-injections were administered, and the effect on CPP, APV and AMSA were recorded. Comparisons were performed between the control and the two EPI-groups and a combination of the two EPI-groups, EPI-all., Result: Compared to the control group, maximum peak of CPP (Pmax) after injection 1 and 2 was significantly increased in the EPI-all group (p = 0.022, p = 0.016), in EPI 0.02-group after injection 2 and 3 (p = 0.023, p = 0.027) and in EPI 0.03-group after injection 1 (p = 0.013). At Pmax, APV increased only after first injection in both the EPI-all and the EPI 0.03-group compared with the control group (p = 0.011, p = 0.018). There was no statistical difference of AMSA at any Pmax. Seven out of 12 animals (58%) in each EPI-group versus 10 out of 12 (83%) achieved spontaneous circulation after CA., Conclusion: In an experimental CA-CPR pig model repeated doses of intravenous EPI results in a significant increase in APV only after the first injection despite increments in CPP also during the following 2 injections indicating inappropriate changes in coronary vascular resistance during subsequent EPI administration.

Objectives: The aim of this study was to confirm the cardioprotective effects of hypothermia using a combination of cold saline and endovascular cooling., Background: Hypothermia has been reported to reduce infarct size (IS) in patients with ST-segment elevation myocardial infarctions., Methods: In a multicenter study, 120 patients with ST-segment elevation myocardial infarctions (<6 h) scheduled to undergo percutaneous coronary intervention were randomized to hypothermia induced by the rapid infusion of 600 to 2,000 ml cold saline and endovascular cooling or standard of care. Hypothermia was initiated before percutaneous coronary intervention and continued for 1 h after reperfusion. The primary end point was IS as a percent of myocardium at risk (MaR), assessed by cardiac magnetic resonance imaging at 4 ± 2 days., Results: Mean times from symptom onset to randomization were 129 ± 56 min in patients receiving hypothermia and 132 ± 64 min in controls. Patients randomized to hypothermia achieved a core body temperature of 34.7°C before reperfusion, with a 9-min longer door-to-balloon time. Median IS/MaR was not significantly reduced (hypothermia: 40.5% [interquartile range: 29.3% to 57.8%; control: 46.6% [interquartile range: 37.8% to 63.4%]; relative reduction 13%; p = 0.15). The incidence of heart failure was lower with hypothermia at 45 ± 15 days (3% vs. 14%, p < 0.05), with no mortality. Exploratory analysis of early anterior infarctions (0 to 4 h) found a reduction in IS/MaR of 33% (p < 0.05) and an absolute reduction of IS/left ventricular volume of 6.2% (p = 0.15)., Conclusions: Hypothermia induced by cold saline and endovascular cooling was feasible and safe, and it rapidly reduced core temperature with minor reperfusion delay. The primary end point of IS/MaR was not significantly reduced. Lower incidence of heart failure and a possible effect in patients with early anterior ST-segment elevation myocardial infarctions need confirmation. (Efficacy of Endovascular Catheter Cooling Combined With Cold Saline for the Treatment of Acute Myocardial Infarction [CHILL-MI]; NCT01379261)., (Copyright © 2014 American College of Cardiology Foundation. Published by Elsevier Inc. All rights reserved.)

Objectives: The study sought to evaluate the relationship between procedural volume and outcomes with radial and femoral approach., Background: RIVAL (RadIal Vs. femorAL) was a randomized trial of radial versus femoral access for coronary angiography/intervention (N = 7,021), which overall did not show a difference in primary outcome of death, myocardial infarction, stroke, or non-coronary artery bypass graft major bleeding., Methods: In pre-specified subgroup analyses, the hazard ratios for the primary outcome were compared among centers divided by tertiles and among individual operators. A multivariable Cox proportional hazards model was used to determine the independent effect of center and operator volumes after adjusting for other variables., Results: In high-volume radial centers, the primary outcome was reduced with radial versus femoral access (hazard ratio [HR]: 0.49; 95% confidence interval [CI]: 0.28 to 0.87) but not in intermediate- (HR: 1.23; 95% CI: 0.88 to 1.72) or low-volume centers (HR: 0.83; 95% CI: 0.52 to 1.31; interaction p = 0.021). High-volume centers enrolled a higher proportion of ST-segment elevation myocardial infarction (STEMI). After adjustment for STEMI, the benefit of radial access persisted at high-volume radial centers. There was no difference in the primary outcome between radial and femoral access by operator volume: high-volume operators (HR: 0.79; 95% CI: 0.48 to 1.28), intermediate (HR: 0.87; 95% CI: 0.60 to 1.27), and low (HR: 1.10; 95% CI: 0.74 to 1.65; interaction p = 0.536). However, in a multivariable model, overall center volume and radial center volume were independently associated with the primary outcome but not femoral center volume (overall percutaneous coronary intervention volume HR: 0.92, 95% CI: 0.88 to 0.96; radial volume HR: 0.88, 95% CI: 0.80 to 0.97; and femoral volume HR: 1.00, 95% CI: 0.94 to 1.07; p = 0.98)., Conclusions: Procedural volume and expertise are important, particularly for radial percutaneous coronary intervention. (A Trial of Trans-radial Versus Trans-femoral Percutaneous Coronary Intervention [PCI] Access Site Approach in Patients With Unstable Angina or Myocardial Infarction Managed With an Invasive Strategy [RIVAL]; NCT01014273)., (Copyright © 2014 American College of Cardiology Foundation. Published by Elsevier Inc. All rights reserved.)

Objectives: This study sought to study the second-generation everolimus-eluting stent (EES) as compared with first-generation sirolimus-eluting (SES) and paclitaxel-eluting stents (PES) in diabetes mellitus (DM) patients., Background: There are limited data available comparing clinical outcomes in this setting with EES and SES, whereas studies comparing EES with PES are not powered for low-frequency endpoints., Methods: All DM patients treated with EES, PES, or SES from January 18, 2007, to July 29, 2011, from the SCAAR (Swedish Coronary Angiography and Angioplasty Registery) were included. The EES was compared with SES or PES for the primary composite endpoint of clinically driven detected restenosis, definite stent thrombosis (ST), and all-cause mortality., Results: In 4,751 percutaneous coronary intervention-treated DM patients, 8,134 stents were implanted (EES = 3,928, PES = 2,836, SES = 1,370). The EES was associated with significantly lower event rates compared with SES (SES vs. EES hazard ratio [HR]: 1.99; 95% confidence interval (CI): 1.19 to 3.08). The same was observed when compared with PES (PES vs. EES HR: 1.33; 95% CI: 0.93 to 1.91) but did not reach statistical significance. These results were mainly driven by lower incidence of ST (SES vs. EES HR: 2.87; 95% CI: 1.08 to 7.61; PES vs. EES HR: 1.74, 95% CI: 0.82 to 3.71) and mortality (SES vs. EES HR: 2.02; 95% CI: 1.03 to 3.98; PES vs. EES HR: 1.69; 95% CI: 1.06 to 2.72). No significant differences in restenosis rates were observed between EES and SES or PES (SES vs. EES HR: 1.26; 95% CI: 0.77 to 2.08; PES vs. EES HR: 1.05; 95% CI: 0.71 to 1.55)., Conclusions: In all-comer DM patients the use of EES was associated with improved outcomes compared with SES and PES mainly driven by lower rates of ST and mortality. These results suggest better safety rather than efficacy with EES when compared with SES or PES., (Copyright © 2012 American College of Cardiology Foundation. Published by Elsevier Inc. All rights reserved.)

Background: Mechanical chest compressions (CCs) have been shown capable of maintaining circulation in humans suffering cardiac arrest for extensive periods of time. Reports have documented a visually normalized coronary blood flow during angiography in such cases (TIMI III flow), but it has never been actually measured. Only indirect measurements of the coronary circulation during cardiac arrest with on-going mechanical CCs have been performed previously through measurement of the coronary perfusion pressure (CPP). In this study our aim was to correlate average peak coronary flow velocity (APV) to CPP during mechanical CCs., Methods: In a closed chest porcine model, cardiac arrest was established through electrically induced ventricular fibrillation (VF) in eleven pigs. After one minute, mechanical chest compressions were initiated and then maintained for 10 minutes upon which the pigs were defibrillated. Measurements of coronary blood flow in the left anterior descending artery were made at baseline and during VF with a catheter based Doppler flow fire measuring APV. Furthermore measurements of central (thoracic) venous and arterial pressures were also made in order to calculate the theoretical CPP., Results: Average peak coronary flow velocity was significantly higher compared to baseline during mechanical chests compressions and this was observed during the entire period of mechanical chest compressions (12 - 39% above baseline). The APV slowly declined during the 10 min period of mechanical chest compressions, but was still higher than baseline at the end of mechanical chest compressions. CPP was simultaneously maintained at > 20 mmHg during the 10 minute episode of cardiac arrest., Conclusion: Our study showed good correlation between CPP and APV which was highly significant, during cardiac arrest with on-going mechanical CCs in a closed chest porcine model. In addition APV was even higher during mechanical CCs compared to baseline. Mechanical CCs can, at minimum, re-establish coronary blood flow in non-diseased coronary arteries during cardiac arrest.

Background: Transcatheter aortic valve implantation (TAVI) is a therapeutic option for high-risk patients with aortic stenosis. Procedural mortality remains high in comparison with conventional aortic valve replacement (AVR) because patients determined for TAVI are commonly denied conventional surgery. We aimed to evaluate access-related complications between the transfemoral (TF) and the transapical (TA) approach and to compare survival between TAVI and conventional AVR in propensity-score-matched patients., Methods: Between January 2008 and November 2009, 40 patients underwent TAVI (TF, n=10; TA, n=30) with the Edwards Sapien bioprosthesis (Edwards Lifesciences, Irvine, CA). Survival and postoperative complications were evaluated between the TF and the TA approach. A comparison of survival was made between the TAVI patients and propensity-score-matched patients undergoing conventional AVR., Results: Successful implantation rate was 92.5% (37 of 40). Thirty-day mortality was 5.0% (2 of 40), and the overall in-hospital mortality was 10.0% (4 of 40). Survival after TAVI was 77% at both 6 months and 1 year. Major vascular complications occurred in 3 of 10 patients (all in the TF group), and 3 of 40 patients (7.5%) suffered cerebrovascular events. A comparison of survival between TAVI and propensity score-matched conventional AVR patients showed no significant difference in either the TA group (p=0.73) or the TF group (p=0.59)., Conclusions: The vascular complications occurring when using the TF approach were probably related to a combination of a wide introducer sheath and heavily calcified femoral arteries in a high-risk population. No serious complications were encountered when using the TA approach. After propensity-score matching, survival with both the TA and TF approaches is similar to that after AVR., (Copyright © 2011 The Society of Thoracic Surgeons. Published by Elsevier Inc. All rights reserved.)

Background: Experimental studies have shown that induction of hypothermia before reperfusion of acute coronary occlusion reduces infarct size. Previous clinical studies, however, have not been able to show this effect, which is believed to be mainly because therapeutic temperature was not reached before reperfusion in the majority of the patients. We aimed to evaluate the safety and feasibility of rapidly induced hypothermia by infusion of cold saline and endovascular cooling catheter before reperfusion in patients with acute myocardial infarction., Methods and Results: Twenty patients with acute myocardial infarction scheduled to undergo primary percutaneous coronary intervention were enrolled in this prospective, randomized study. After 4 ± 2 days, myocardium at risk and infarct size were assessed by cardiac magnetic resonance using T2-weighted imaging and late gadolinium enhancement imaging, respectively. A core body temperature of <35°C (34.7 ± 0.3°C) was achieved before reperfusion without significant delay in door-to-balloon time (43 ± 7 minutes versus 40 ± 6 minutes, hypothermia versus control, P=0.12). Despite similar duration of ischemia (174 ± 51 minutes versus 174 ± 62 minutes, hypothermia versus control, P=1.00), infarct size normalized to myocardium at risk was reduced by 38% in the hypothermia group compared with the control group (29.8 ± 12.6% versus 48.0 ± 21.6%, P=0.041). This was supported by a significant decrease in both peak and cumulative release of Troponin T in the hypothermia group (P=0.01 and P=0.03, respectively)., Conclusions: The protocol demonstrates the ability to reach a core body temperature of <35°C before reperfusion in all patients without delaying primary percutaneous coronary intervention and that combination hypothermia as an adjunct therapy in acute myocardial infarction may reduce infarct size at 3 days as measured by MRI., Clinical Trial Registration: URL: http://www.clinicaltrials.gov. Unique identifier: NCT00417638.

Background: Ectonucleotidase dependent adenosine generation has been implicated in preconditioning related cardioprotection against ischemia-reperfusion injury, and treatment with a soluble ectonucleotidase has been shown to reduce myocardial infarct size (IS) when applied prior to induction of ischemia. However, ectonucleotidase treatment according to a clinically applicable protocol, with administration only after induction of ischemia, has not previously been evaluated. We therefore investigated if treatment with the ectonucleotidase apyrase, according to a clinically applicable protocol, would reduce IS and microvascular obstruction (MO) in a large animal model., Methods: A percutaneous coronary intervention balloon was inflated in the left anterior descending artery for 40 min, in 16 anesthetized pigs (40-50 kg). The pigs were randomized to 40 min of 1 ml/min intracoronary infusion of apyrase (10 U/ml, n = 8) or saline (0.9 mg/ml, n = 8), twenty minutes after balloon inflation. Area at risk (AAR) was evaluated by ex vivo SPECT. IS and MO were evaluated by ex vivo MRI., Results: No differences were observed between the apyrase group and saline group with respect to IS/AAR (75.7 +/- 4.2% vs 69.4 +/- 5.0%, p = NS) or MO (10.7 +/- 4.8% vs 11.4 +/- 4.8%, p = NS), but apyrase prolonged the post-ischemic reactive hyperemia., Conclusion: Apyrase treatment according to a clinically applicable protocol, with administration of apyrase after induction of ischemia, does not reduce myocardial infarct size or microvascular obstruction.

Purpose: The aim of this study was to examine whether the retinal circulation in the pig can be accessed using interventional neuroradiology and to explore the possibility of creating occlusions that result in experimental retinal ischemia., Methods: Six experiments were performed using 100-kg pigs. The external carotid system was catheterized using a fluoroscopy-monitored, transfemoral, endovascular approach. Transient and permanent vascular occlusions were performed using an angioplasty balloon catheter or a liquid embolic agent that was administered via an injection-catheter., Results: A technique for transfemoral catheterization of arteries supplying the retina was established. The ophthalmic artery was demonstrated to give rise to the main ciliary artery from which the retinal artery branched as a single artery or as several arteries. A balloon-catheter could be introduced into the ophthalmic artery but not into the main ciliary artery. An injection-catheter could, in all experiments, be introduced into the main ciliary artery and, in some experiments, into the retinal artery. Occlusion of the ophthalmic artery, over the branching of the main ciliary artery, caused incomplete ischemia, presumably because of collaterals feeding the distal parts of the vasculature. Multifocal ERG (mfERG) recordings showed decreased amplitudes and increased implicit times, indicating retinal ischemia. Occlusion of the ciliary and retinal arteries caused complete ischemia, as shown by complete flattening of the mfERG recordings and, by indirect ophthalmoscopy, blanching of the retinal arteries and a pale retina,, Conclusions: The authors show for the first time that the ophthalmic and retinal artery can be catheterized using a transfemoral endovascular approach. This technique may be useful to produce clear-cut experimental retinal ischemia.

Background: In experimentally induced myocardial infarction, mild hypothermia (33-35 degrees C) is beneficial if applied prior to ischemia or reperfusion. Hypothermia, when applied after reperfusion seems to confer little or no benefit. The mechanism by which hypothermia exerts its cell-protective effect during cardiac ischemia remains unclear. It has been hypothesized that hypothermia reduces the reperfusion damage; the additional damage incurred upon the myocardium during reperfusion. Reperfusion results in a massive increase in blood flow, reactive hyperemia, which may contribute to reperfusion damage. We postulated that hypothermia could attenuate the post-ischemic reactive hyperemia., Methods: Sixteen 25-30 kg pigs, in a closed chest model, were anesthetized and temperature was established in all pigs at 37 degrees C using an intravascular cooling catheter. The 16 pigs were then randomized to hypothermia (34 degrees C) or control (37 degrees C). The left main coronary artery was then catheterized with a PCI guiding catheter. A Doppler flow wire was placed in the mid part of the LAD and a PCI balloon was then positioned proximal to the Doppler wire but distal to the first diagonal branch. The LAD was then occluded for ten minutes in all pigs. Coronary blood flow was measured before, during and after ischemia/reperfusion., Results: The peak flow seen during post-ischemic reactive hyperemia (during the first minutes of reperfusion) was significantly reduced by 43 % (p < 0.01) in hypothermic pigs compared to controls., Conclusion: Mild hypothermia significantly reduces post-ischemic hyperemia in a closed chest pig model. The reduction of reactive hyperemia during reperfusion may have an impact on cardiac reperfusion injury.

Background: The same mechanisms by which ultrasound enhances thrombolysis are described in connection with non-beneficial effects of ultrasound. The present safety study was therefore designed to explore effects of beneficial ultrasound characteristics on the infarcted and non-infarcted myocardium., Methods: In an open chest porcine model (n = 17), myocardial infarction was induced by ligating a coronary diagonal branch. Pulsed ultrasound of frequency 1 MHz and intensity 0.1 W/cm2 (ISATA) was applied during one hour to both infarcted and non-infarcted myocardial tissue. These ultrasound characteristics are similar to those used in studies of ultrasound enhanced thrombolysis. Using blinded assessment technique, myocardial damage was rated according to histopathological criteria., Results: Infarcted myocardium exhibited a significant increase in damage score compared to non-infarcted myocardium: 6.2 +/- 2.0 vs. 4.3 +/- 1.5 (mean +/- standard deviation), (p = 0.004). In the infarcted myocardium, ultrasound exposure yielded a further significant increase of damage scores: 8.1 +/- 1.7 vs. 6.2 +/- 2.0 (p = 0.027)., Conclusion: Our results suggest an instantaneous additive effect on the ischemic damage in myocardial tissue when exposed to ultrasound of stated characteristics. The ultimate damage degree remains to be clarified.

The physiological mechanisms that regulate reactive hyperemia are not fully understood. We postulated that the endothelial P2Y(1) receptor that release vasodilatory factors in response to ADP might play a vital role in the regulation of coronary flow. Intracoronary flow was measured with a Doppler flow-wire in a porcine model. 2-MeSADP (10(-5) M), ATP (10(-4) M) or UTP (10(-4) M) alone or as co-infusion with a selective P2Y(1) receptor blocker, MRS 2179 (10(-3) M) was locally delivered through the tip of a coronary angioplasty balloon. In separate pigs the coronary artery was occluded with the balloon for 10 min. During the first and tenth minutes of coronary ischemia, 2.5 ml of MRS 2179 (10(-3) M) was delivered distal to the occlusion in 8 pigs, 10 pigs were used as controls. MRS 2179 fully inhibited the 2-MeSADP-mediated coronary flow increase (P < 0.05) with no effect on UTP, indicating selective P2Y(1) inhibition. ATP-mediated flow increase was significantly inhibited by MRS 2179. During reactive hyperemia following coronary occlusion, flow increased by nearly sevenfold. MRS 2179, however, reduced the post-ischemic hyperemia by a mean of 46% during the period 1-2.5 min following balloon deflation (P < 0.05), which corresponds to peak velocity flow during reperfusion. In conclusion, MRS 2179, a selective P2Y(1) receptor blocker, significantly reduces the increased coronary flow caused both by 2-MeSADP and reactive hyperemia in coronary arteries. Thus, ADP acting on the endothelial P2Y(1) receptor may play a major role in coronary flow during post-ischemic hyperemia.