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This study examined the association between cardiopulmonary bypass (CPB) hematocrit and postoperative acute renal failure (ARF) in patients undergoing aortic arch surgery with hypothermic circulatory arrest. The Society of Thoracic Surgeons Adult Cardiac Surgery Database was queried from 2011 to 2019 for patients undergoing aortic arch surgery with hypothermic circulatory arrest. A multivariable logistic regression model estimated the adjusted odds of postoperative ARF on the basis of CPB hematocrit. Effects were stratified by preoperative kidney function and the duration of hypothermic circulatory arrest by using interaction terms. The study also investigated the association between postoperative ARF and major postoperative outcomes by using multivariable regression models. On adjusted analysis, higher CPB hematocrit (>20%-25%, >25%-30%, >30%) was associated with lower odds of ARF as compared with lower CPB hematocrit (≤20%) (>20-25%, aOR, 0.78; 95% CI, 0.65-0.93; P =.006; >25%-30%, aOR, 0.65; 95% CI, 0.50-0.84; P =.0007; >30%, aOR, 0.45; 95% CI, 0.28-0.72; P =.0008). The predicted probability of postoperative ARF by CPB hematocrit was higher in patients with lower preoperative renal function (estimated glomerular filtration rate, <60 mL/min/1.73 m2) (interaction P =.03). The association between hematocrit and postoperative ARF was not significantly modified by hypothermic circulatory arrest time (interaction P =.74). All postoperative outcomes were significantly worse in patients with postoperative ARF (all P <.0001). Among patients undergoing aortic arch surgery, a higher CPB hematocrit level is associated with reduced likelihood of postoperative ARF. Preoperative renal function, but not hypothermic circulatory arrest duration, significantly modified this association. The maintenance of higher CPB hematocrit may reduce the incidence of postoperative ARF, especially for patients with poor preoperative renal function. [ABSTRACT FROM AUTHOR]

Approximately one-quarter of patients with acute type A aortic dissection (TAAD) present with concomitant malperfusion of coronary arteries, mesenteric circulation, lower extremities, kidneys, brain, and/or coma. It is generally accepted that TAAD patients who present with malperfusion experience higher mortality rates than patients without, although how specific malperfusion syndromes, alone or in combination, affect mortality is not well described. The International Registry of Acute Aortic Dissection database was queried for patients who underwent surgical repair of TAAD. Patients were stratified according to the presence/absence of malperfusion at presentation. Multivariable logistic regression was used to evaluate in-hospital mortality according to malperfusion type. Kaplan–Meier estimates were used to estimate 30-day postoperative survival. Six thousand four hundred thirty-seven patients underwent surgical repair of acute TAAD, of whom 2642 (41%) had 1 or more preoperative malperfusion syndromes. Mesenteric malperfusion (adjusted odds ratio [AOR], 4.84; P <.001) was associated with the highest odds of in-hospital mortality, followed by coma (AOR, 1.88; P =.007), limb ischemia (AOR, 1.73; P =.008), and coronary malperfusion (AOR, 1.51; P =.02). Renal malperfusion (AOR, 1.37; P =.24) and neurologic deficit (AOR, 1.35; P =.28) were not associated with increased in-hospital mortality. In patients who survived to discharge, there was no difference in 1-year postdischarge survival in the malperfusion and no malperfusion cohorts (P =.36). Survival during the index admission after TAAD repair varies according to the presence and type of malperfusion syndromes, with mesenteric malperfusion being associated with the highest odds of in-hospital death. Not only the presence of malperfusion but rather specific malperfusion syndromes should be considered when assessing a patient's risk of undergoing TAAD repair. [Display omitted] [ABSTRACT FROM AUTHOR]

The current management of acute complicated type B aortic dissection is a combination of medical therapy and endovascular repair. Endovascular repair is not feasible when the dissection extends into the aortic arch. We describe 3 patients with acute type B aortic dissection complicated by retrograde arch extension and visceral malperfusion who were successfully treated with a total arch replacement and frozen elephant trunk. [ABSTRACT FROM AUTHOR]

Patients undergoing surgical aortic valve replacement (SAVR) are at risk of developing prolonged atrial fibrillation (AF) after surgery. Prophylactic interventions such as left atrial appendage amputation (LAAA) and pulmonary vein isolation (PVI) impose cost and operative risk, discouraging routine use. To guide such interventions, we investigated preoperative predictors of AF. A retrospective analysis was performed on patients undergoing SAVR between 2011 and 2017. Patients were excluded if they had a preoperative history of AF or underwent a LAAA or PVI. Baseline characteristics were compared between those who did and did not develop prolonged postoperative AF. Predictors of prolonged AF were identified using multivariable logistic regression. Of 720 patients identified, 170 (25%) developed prolonged (beyond 30 days) AF. Compared with patients who did not develop AF, those who developed prolonged AF were older (70.1 vs 62.4 years, P <.001), had a greater incidence of hypertension (78% vs 61%, P <.001), and were less likely to smoke (16% vs 31%, P <.01). On multivariable regression, older age (odds ratio, 1.05; P <.01) and left atrial enlargement (odds ratio, 1.66; P =.04) were predictors of prolonged AF. In this high-risk cohort, the incidence of prolonged postoperative AF was 40%. Older age and left atrial enlargement identify a stratum of patients at high risk of developing prolonged postoperative AF after SAVR. Multicenter, prospective studies should investigate the value of prophylactic interventions such as LAAA, Cox maze, or PVI in these individuals to obviate the consideration of late anticoagulation. Advanced age and left atrial enlargement are risk factors for prolonged AF after SAVR. [ABSTRACT FROM AUTHOR]

Summary Ciliopathies are a group of genetic disorders caused by a failure to form functional cilia. Due to a lack of structural information, it is currently poorly understood how ciliopathic mutations affect protein functionality to give rise to the underlying disease. Using X-ray crystallography, we show that the ciliopathy-associated centriolar protein CEP120 contains three C2 domains. The point mutations V194A and A199P, which cause Joubert syndrome (JS) and Jeune asphyxiating thoracic dystrophy (JATD), respectively, both reduce the thermostability of the second C2 domain by targeting residues that point toward its hydrophobic core. Genome-engineered cells homozygous for these mutations have largely normal centriole numbers but show reduced CEP120 levels, compromised recruitment of distal centriole markers, and deficient cilia formation. Our results provide insight into the disease mechanism of two ciliopathic mutations in CEP120, identify putative binding partners of CEP120 C2B, and suggest a complex genotype-phenotype relation of the CEP120 ciliopathy alleles. [ABSTRACT FROM AUTHOR]

Background To report a new technique for diameter correction in patients after thoracic endovascular aortic repair (TEVAR) with large stent-grafts using the Vascutek Siena 4-branch collared prosthesis (Vascutek Terumo, Inchinnan, Scotland, UK) in patients undergoing thoracoabdominal (TA) aortic replacement. Methods Within a 24-month period, 39 patients underwent TA replacement at our center. Of these, 6 patients had undergone previous TEVAR with large stent-grafts (42 to 48 mm diameter). Indications for TEVAR were aneurysm formation in 3 patients and residual type B aortic dissection (status post repair of type A dissection) in 3 patients. In these patients, the Vascutek Siena 4-branch prosthesis was used in a reversed fashion, removing the elephant trunk portion and using the sewing collar for diameter correction at the anastomotic site. Results No 30-day mortality and no stroke or symptomatic spinal cord ischemia was observed. Median diameter of the TEVAR graft at the anastomotic site was 44 mm. Median size of the Siena graft used was 26 mm. Diameter correction was successfully achieved in all patients by tailoring the sewing collar of the Siena 4-branch prosthesis to the individual need according to the diameter of the distal end of the stent-graft. Conclusions Using the sewing collar of the Vascutek Siena 4-branch prosthesis for diameter correction in patients undergoing TA replacement after previous TEVAR with large stent-grafts adds a useful adjunct to the armamentarium of options in a growing patient population. [ABSTRACT FROM AUTHOR]

Drug use–associated infective endocarditis is a rapidly growing clinical problem. Although operative outcomes are generally satisfactory, reinfection secondary to recurrent substance use is distressingly common, negatively affects long-term survival, generates practical and ethical challenges, and creates potential conflict among care team members. We established a Drug Use Endocarditis Treatment team including surgeons, infectious disease, and addiction medicine experts specifically focused on the unique complexities of drug use–associated infective endocarditis. We reviewed the impact of Drug Use Endocarditis Treatment team involvement on quantitative measures of quality of care, including length of stay, time to addiction medicine consultation, time to surgery, and discharge on appropriate medications for opioid use disorder, as well as operative mortality. Standard statistical tests were used, including the Fisher exact test, t test, and Wilcoxon rank-sum test. Qualitative assessment was made of the impact on clinicians, including communication and mutual understanding. Comparing the pre–Drug Use Endocarditis Treatment cohort with the post–Drug Use Endocarditis Treatment cohort, patients in the post–Drug Use Endocarditis Treatment cohort who underwent surgery had a significantly lower time from admission to addiction medicine consultation (3.8 vs 1.0 days P <.001) and clinically relevant increase in discharge on medications for opioid use disorder (48% vs 67% P =.35). Additionally, involved members of the team thought communication was improved. The Drug Use Endocarditis Treatment team improved engagement with addiction medicine consultation and appropriate discharge care. Given the impact of relapse of injection drug use on long-term outcomes, interventions such as this offer potentially powerful tools for the treatment of this complex patient population. The patient cohort groups (left column), the time to addiction medicine consultation for each cohort, survey results (middle column), and implications of the study (right column). For the time to addiction medicine consultation figure (top middle column), the lower and upper borders of the box represent the first and third quartiles, respectively. The ends of the whiskers represent the minimum and maximum days to addiction medicine consultation, and the horizontal line indicates the median. [Display omitted] [ABSTRACT FROM AUTHOR]

This work investigates the feasibility of real-time motion monitoring (MM) using orthogonal cine MRI during MR guided Adaptative Radiation Therapy (MRgART) for liver tumors that are normally invisible on cine MRI with no contrast agent. An investigational package, Motion Monitoring Research Package (MMRP), was developed to measure real-time target motion between orthogonal cine MRI and the daily baseline 3D MRI. The MMRP package was evaluated on 8 liver cancer patients treated on a 1.5T MR-Linac. For all patients, a 3D mid-position (MidP) image derived from a daily 4D MRI was used to delineate a sub-liver volume (SLV) encompassing the tumor. During the same session, real-time 2D T2/T1-weighted bFFE cine MRI were collected with free breathing during MRgART. The cine images were acquired with a temporal resolution of 200 ms interleaved between coronal and sagittal orientations. MMRP workflow included two steps: (1) creating a 2D template in each orientation using cine data acquired over the first 12 s, followed by a rigid registration between the combined templates and the MidP image over the SLV region; (2) measuring the SLV motion by registering the rest of the 2D cine series with the corresponding template. To evaluate the MM accuracy from MMRP, the ground-truth contours on cine MRI were created manually. Common visible vessels and segments of liver boundaries in proximity to the tumor were used as anatomical landmarks for reproducible delineations on both the 3D and cine images. MM accuracy was measured using the standard deviation of the error (SDE) to compare the center of mass position of the ground-truth and the monitored motion. Maximum of tumor motion was assessed on 4D MRI. In 6 of the 8 cases, the assessed mean (range) centroid motions were 8.8 (4.6-13.8), 1.5 (0.7-2.8) and 3.2 (1.5-5) mm with mean SDE (range) values of 1.2 (0.7-1.6), 0.94 (0.4-1.7), and 1 (0.4-1.4) mm in superior inferior (SI), left right, and anterior posterior (AP) directions, respectively. The mean (range) of the maximum tumor motion from the 4D MRI was 8 (5-11) mm in SI direction, smaller than the centroid MM, indicating the importance of motion capture using the MM in real-time. For the remaining two cases, quantitative MM was challenging due to target deformation and large through-plane motion in the AP direction. We have demonstrated the feasibility of accurate real-time MM of a liver tumor using a sub-liver volume as a tumor surrogate, based on real-time orthogonal cine MRI during MRgART. The approach overcomes difficulty due to the invisibility of liver tumor on the T2/T1-w 2D cine without using a contrast agent and the need of implanting radio-opaque clips or the approximation of the whole liver motion as the tumor motion. With further investigation with more patient data, the real-time MM technique may be implemented in MRgART to manage intrafraction liver motion. [ABSTRACT FROM AUTHOR]

Summary Cilia are thin cell projections with essential roles in cell motility, fluid movement, sensing, and signaling. They are templated from centrioles that dock against the plasma membrane and subsequently extend their peripheral microtubule array. The molecular mechanisms underpinning cilia assembly are incompletely understood. Cep104 is a key factor involved in cilia formation and length regulation that rides on the ends of elongating and shrinking cilia. It is mutated in Joubert syndrome, a genetically heterogeneous ciliopathy. Here we provide structural and biochemical data that Cep104 contains a tubulin-binding TOG (tumor overexpressed gene) domain and a novel C2HC zinc finger array. Furthermore, we identify the kinase Nek1, another ciliopathy-associated protein, as a potential binding partner of this array. Finally, we show that Nek1 competes for binding to Cep104 with the distal centriole-capping protein CP110. Our data suggest a model for Cep104 activity during ciliogenesis and provide a novel link between Cep104 and Nek1. [ABSTRACT FROM AUTHOR]

Objective We describe an alternate technique for establishing antegrade cerebral perfusion (ACP) during hypothermic circulatory arrest via direct, central cannulation of the innominate artery. Methods From 2009 to 2015, 100 elective hemiarch reconstructions for proximal aortic aneurysms were performed under moderate hypothermic circulatory arrest (MHCA). Cerebral perfusion was instituted with ACP via direct cannulation of the innominate artery. Results Mean patient age was 63 ± 13 years (72 men; 72%). Mean MHCA temperature was 27.3°C ± 1.0°C (median, 28°C). Mean ACP time was 17 ± 4 minutes and mean crossclamp time was 134 ± 42 minutes. Proximal reconstruction included root replacement with composite valved graft (n = 47), valve sparing root reimplantation (n = 16), and aortic valve replacement (n = 19). In-hospital 30-day mortality (n = 1; 1%), stroke (1; 1%), reversible ischemic neurologic deficit (n = 1; 1%), coma (n = 0), and renal failure (n = 1; 1%) rates were low. There was no incidence of injury or dissection of the innominate artery. Conclusions Direct, central innominate artery cannulation for ACP yields excellent outcomes. This technique is safe, provides excellent cerebral protection during circulatory arrest and simplifies the circulatory management strategy for elective ascending aortic and hemiarch reconstruction. [ABSTRACT FROM AUTHOR]

Functional, pasting, rheological and thermal properties of two commercial rice flours (Basmati and Giza-177) as function of particle size (74–595 μm) were studied. The protein, total starch and amylose contents decreased with decreasing particles whereas lipid contents increased at similar condition. Basmati particle fractions had the highest amount of amylose contents (10.1–18.8%) than the Giza fractions (8.5–11.9%). The water absorption capacity of Giza rice was superior than the Basmati rice and the water holding capacity of both samples increased abruptly at 70 °C. The peak complex viscosity increased with fineness of the particle during non-isothermal heating. At isothermal condition, the mechanical rigidity vs particle size behaved differently at above and below the gelatinization temperature. The viscoamylographic peak viscosity of Giza rice had edge over the Basmati rice and the value decreased with reducing the particle size. Pasting temperature determined by viscoamylograph and rheometer did not show good correlations for particle fractions. Two endothermic peaks were detected for each rice fractions and the gelatinization temperature of Basmati flour was affected by the particle size. Scanning electron microscopy did not show any difference between two rice samples. Overall, particle size fractionation of rice flour would provide an opportunity to produce food product with desired functionality, texture and nutrients. [ABSTRACT FROM AUTHOR]

Background Aortic reoperations are technically challenging. This study evaluated outcomes after “true” redo root replacement (previous full root replacement) stratified by cause of prosthesis failure. Methods Data were compared for 793 patients who underwent a first-time sternotomy (de novo group) and 120 patients who had previously undergone full aortic root replacement (redo group), of which 76 underwent reoperation due to structural valve deterioration (degenerative group), and 44 due to endocarditis (infection group). Results Overall mortality was 4% (n = 28) in the de novo group and 5% (n = 6) in the redo group ( p = 0.43) (degenerative group, 3%, infection group, 9%; p = 0.19). The infection group had an increased incidence of renal failure, sternal infection, prolonged ventilation, reoperation for bleeding, multisystem failure, and sepsis, and an increased hospital length of stay. The degenerative group and the de novo group had a similar risk of perioperative death and major complications. The 5-year survival was 86.3% ± 1.3% for the de novo group and 77.3% ± 4.6% for the redo group ( p ≤ 0.01; degenerative, 86.3% ± 5%; infection, 65.3% ± 7.7%; p < 0.01; p = 0.98 for de novo vs degenerative). Multivariate analysis demonstrated that reoperation for degenerative failure did not increase the risk of perioperative or late death. Conclusions Redo aortic root replacement can be performed with low perioperative morbidity and death. The presence of infection increases the risk of complications and worsens survival. However, redo root replacement for degenerative failure can be performed with similar short-term complication risk and midterm survival as de novo root replacement. [ABSTRACT FROM AUTHOR]

Background Deep hypothermic circulatory arrest (DHCA) with retrograde cerebral perfusion (DHCA group) has traditionally been the cerebral protection strategy during transverse hemiarch aortic reconstruction. Recently, we have adopted moderate hypothermic (≥25°C) circulatory arrest (MHCA) with antegrade cerebral perfusion (MHCA group). We compared the outcomes for these two circulatory arrest management strategies. Methods From 2008 to 2012, in a concurrent series of 376 patients (DHCA, 301; MHCA, 75) undergoing transverse hemiarch for aortic aneurysm disease, incidences of concomitant root replacement (44% vs 47%, p = 0.8), and aortic valve replacement (29% vs 21%, p = 0.3) were similar, although atherosclerotic aneurysm pathology was present in patients in the MHCA group (71% vs 33%, p < 0.01). Antegrade cerebral perfusion was established via axillary artery or direct innominate artery cannulation. A database was prospectively maintained. Results MHCA group patients were older (66 ± 11 vs 60 ± 14 years; p < 0.01). Other demographics were similar. Aortic cross-clamp (128 ± 46 vs 163 ± 57 minutes, p < 0.01) and cardiopulmonary bypass (167 ± 49 vs 222 ± 61 minutes, p < 0.01) times were lower in the MHCA group. Transfusion requirements were significantly reduced with MHCA (38% vs 61%, p < 0.01), especially use of fresh frozen plasma and cryoprecipitate. Direct innominate artery cannulation did not result in any vascular or neurologic complication. Postoperative outcomes were similar. In-hospital and 30-day mortality was 1% in both groups. Stroke (0% vs 2%) and hemodialysis rates (0% vs 1%) were also similar. Conclusions MHCA with antegrade cerebral perfusion yields excellent and equivalent outcomes to DHCA for elective aortic hemiarch reconstruction. MHCA significantly improves intraoperative times and, importantly, reduces transfusion requirements compared with DHCA with a retrograde cerebral perfusion strategy. [ABSTRACT FROM AUTHOR]

Recent evidence has shown that moderate mitral regurgitation is common and clinically relevant in patients presenting for surgical and transcatheter aortic valve replacement for aortic stenosis. Prospective multicenter clinical trials are now indicated to resolve the clinical equipoise about whether or not mitral valve intervention also is indicated at the time of aortic valve intervention. Advances in three-dimensional transesophageal echocardiography, transcatheter mitral interventions, and surgical aortic valve replacement, including the advent of sutureless valves, likely will expand the therapeutic possibilities for moderate mitral regurgitation in the setting of aortic valve interventions for severe aortic stenosis. [Copyright &y& Elsevier]

Background. Surgical techniques for aortic valve (AV) repair are directed toward restoring normal structural relationships in the aortic root and rely on detailed assessment of root and valve anatomy. Noninvasive three-dimensional (3D) imaging and modeling may assist in patient selection and operative planning. Methods. Transesophageal real-time 3D echocardiographic images of 5 patients with normal AVs were acquired. The aortic root and the annulus were manually segmented at end diastole using a 36-point rotational template. The AV leaflets and the coaptation zone were manually segmented in parallel 1-mm cross sections. Quantitative 3D models of the AV and root were generated and used to measure standard anatomic parameters and were compared to conventional two-dimensional echocardiographic measurements. All measurements are given as mean ± SD. Results. Annular, sinus, and sinotubular junction areas were 4.1 ± 0.6 cm², 7.5 ± 1.2 cm², and 3.9 ± 1.0 cm², respectively. Root diameters (measured in three locations) by 3D model inspection and two-dimensional echocardiography measurement correlated (R² = 0.75). Noncoapted areas of the left, right, and noncoronary leaflets were 1.9 ± 0.2 cm², 1.6 ± 0.3 cm², and 1.6 ± 0.3 cm², respectively. Mean coaptation areas for the left-right, left-noncoronary, and right-noncoronary coaptation zones were 87.7 ± 36.9 mm², 69.9 ± 20.7 mm², and 114.2 ± 23.0 mm², respectively. The mean ratio of noncoapted leaflet area to annular area was 1.3 ± 0.2. Conclusions. High-resolution 3D models of the in vivo normal human aortic root and valve were generated using 3D echocardiography. Quantitative 3D models and analysis may assist in characterization of pathology and decision making for AV repair. [ABSTRACT FROM AUTHOR]

Background. The saddle shape of the normal mitral annulus has been quantitatively described by several groups. There is strong evidence that this shape is important to valve function. A more complete understanding of regional annular geometry in diseased valves may provide a more educated approach to annuloplasty ring selection and design. We hypothesized that mitral annular shape is markedly distorted in patients with diseased valves. Methods. Real-time 3-dimensional echocardiography was performed in 20 patients with normal mitral valves, 10 with ischemic mitral regurgitation, and 20 with myxomatous mitral regurgitation (MMR). Thirty-six annular points were defined to generate a 3-dimensional model of the annulus. Regional annular parameters were measured from these renderings. Left ventricular inner diameter was obtained from 2-dimensional echocardiographic images. Results. Annular geometry was significantly different among the three groups. The annuli were larger in the MMR and in the ischemic mitral regurgitation groups. The annular enlargement was greater and more pervasive in the MMR group. Both diseases were associated with annular flattening, although though the regional distribution of that flattening was different between groups. Left ventricular inner diameter was increased in both groups. However, relative to the Left ventricular inner diameter, the annulus was disproportionately dilated in the MMR group. Conclusions. Patients with MMR and ischemic mitral regurgitation have enlarged and flattened annuli. In the case of MMR, annular distortions may be the driving factor leading to valve incompetence. These data suggest that the goal of annuloplasty should be the restoration of normal annular saddle shape and that the use of flexible, partial, and fiat rings may be ill advised. [ABSTRACT FROM AUTHOR]

Background: Restoring leaflet coaptation is the primary objective in repair of ischemic mitral regurgitation (IMR). The common practice of placing an undersized annuloplasty ring partially achieves this goal by correcting annular dilation; however, annular reduction has been demonstrated to exacerbate posterior leaflet tethering. Using a sheep model of IMR, we tested the hypothesis that posterior leaflet augmentation (PLA) combined with standard annuloplasty sizing increases leaflet coaptation more effectively than undersized annuloplasty alone. Methods: Eight weeks after posterobasal myocardial infarction, 15 sheep with 2+ or greater IMR underwent annuloplasty with either a 24-mm annuloplasty ring (24-mm group, n = 5), 30-mm ring (30-mm group, n = 5), or 30-mm ring with concomitant augmentation of the posterior leaflet (PLA group, n = 5). Using three-dimensional echocardiography, postrepair coaptation zone and posterior leaflet mobility were assessed. Results: Leaflet coaptation length after repair was greater in the PLA group (4.1 ± 0.3 mm) and the 24-mm group (3.8 ± 0.5 mm) as compared with the 30-mm group (2.7 ± 0.6 mm, p < 0.01). Leaflet coaptation area was significantly greater in the PLA group (121.5 ± 6.6 mm2) as compared with the 30-mm group (77.5 ± 17.0 mm2) or the 24-mm group (92.5 ± 17.9 mm2, p < 0.01). Posterior leaflet mobility was significantly greater in the PLA group as compared with the 30-mm group or the 24-mm group. Conclusions: Posterior leaflet augmentation combined with standard-sized annuloplasty enhances leaflet coaptation more effectively than either standard-sized annuloplasty or undersized annuloplasty alone. Increased leaflet coaptation after PLA provides redundancy to IMR repair, and may decrease incidence of both recurrent IMR and mitral stenosis. [ABSTRACT FROM AUTHOR]

Background: Using human mitral valve (MV) models derived from three-dimensional echocardiography, finite element analysis was used to predict mechanical leaflet and chordal stress. Subsequently, valve geometries were altered to examine the effects on stresses of the following: (1) varying coaptation area; (2) varying noncoapted leaflet tissue area; and (3) varying interleaflet coefficient of friction (μ). Methods: Three human MV models were loaded with a transvalvular pressure of 80 mm Hg using finite element analysis. Initially leaflet coaptation was set to 10%, 50%, or 100% of actual coaptation length to test the influence of coaptation length on stress distribution. Next, leaflet surface areas were augmented by 1% overall and by 2% in the noncoapted “belly” region to test the influence of increased leaflet billowing without changing the gross geometry of the MV. Finally, the coefficient of friction between the coapted leaflets was set to μ = 0, 0.05, or 0.3, to assess the influence of friction on MV function. Results: Leaflet coaptation length did not affect stress distribution in either the coapted or noncoapted leaflet regions; peak leaflet stress was 0.36 ± 0.17 MPa at 100%, 0.35 ± 0.14 MPa at 50%, and 0.35 ± 0.15 MPa at 10% coaptation lengths (p = 0.85). Similarly, coaptation length did not affect peak chordal tension (p = 0.74). Increasing the noncoapted leaflet area decreased the peak valvular stresses by 5 ± 2% (p = 0.02). Varying the coefficient of friction between leaflets did not alter leaflet or chordal stress distribution (p = 0.18). Conclusions: Redundant MV leaflet tissue reduces mechanical stress on the noncoapted leaflets; the extent of coaptation or frictional interleaflet interaction does not independently influence leaflet stresses. Repair techniques that increase or preserve noncoapted leaflet area may decrease mechanical stresses and thereby enhance repair durability. [ABSTRACT FROM AUTHOR]

Background: Endocarditis affecting the aortic valve, with abscess formation and root destruction, remains a challenge to treat. Aortic root homografts have been advocated because of a perceived lower risk of infective complications than with other root replacement grafts. However, the theoretical advantage of homografts has not been re-evaluated in the modern era. This report is based on an examination of our results for all aortic root replacements in complex, active endocarditis affecting the aortic valve. Methods: From 2000 to 2010, 134 patients (70.9% male; mean age 58.3 ± 14.8 years) at our institution underwent aortic root replacement for active endocarditis. Ninety of the patients (67.2%) had a previously implanted prosthetic aortic valve. Our findings for these patients included one or more of the following: abscess (n = 110, 82.1%), valve vegetation (n = 98, 73.1%), and pseudoaneurysm or rupture or both (n = 62, 46.3%). We retrospectively reviewed data for the patients from hospital records and the social security data base. Results: A mechanical composite graft (MC) was used in 43 of the patients (32.1%), a non-homograft biologic valve conduit (BC) in 55 patients (41.0%), and a homograft (HG) valve in 36 patients (26.9%). There was no significant difference among the groups in the incidence of major complications or in-hospital mortality. During a mean follow-up of 32.1 ± 29.4 months, the rates of readmission, reinfection, and reoperation were similar for the three groups. The mean 5-year survival in the study was 58 ± 9% for the MC group, 62 ± 7% for the BC group, and 58 ± 9% for the HG group, respectively (p = 0.48). Conclusions: Aortic root replacement in the presence of complex active infection is associated with significant morbidity and mortality. We report that the rates of major complications and late mortality were similar among MC, BC, and HG groups in our study. [Copyright &y& Elsevier]

Background: Cardiac surgery in Jehovah''s Witnesses poses unique challenges. We have developed a comprehensive multimodality program for these patients and have obtained excellent results. Methods: Ninety-one Jehovah''s Witness patients underwent cardiac surgery between 2000 and 2010. Preoperative, intraoperative, and postoperative considerations in the conduct of bloodless surgery in the Jehovah''s Witness population are discussed. Mortality for isolated coronary artery bypass graft surgery and isolated aortic valve replacement was compared with predicted mortality from The Society of Thoracic Surgeons (STS) risk models. Perioperative outcomes were stratified by urgent and elective status of operations. Results: Mean age was 65 ± 12.4 years. Comorbid conditions included hypertension (84.6%), diabetes mellitus (48.4%), previous myocardial infarction (23.1%), chronic lung disease (38.5%), peripheral vascular disease (20.9%), and renal failure (11%). In-hospital mortality was 5.5% (n = 5). Mortality for isolated coronary artery bypass graft surgery and isolated aortic valve replacement was 2.2% (observed to expected ratio = 1.05, 95% confidence interval: 0 to 3.02) and 5.6% (observed to expected = 1.46, 95% confidence interval: 0 to 3.76), respectively. Other complications included reoperation (all = 8.8%, cardiac = 2.2%), sepsis (2.2%), sternal wound infection (1.1%), transient ischemic attack (1.1%), renal failure requiring dialysis (1.1%), and prolonged ventilation (18.7%). Major complication rates were not significantly different between the elective group and the urgent group. Conclusions: Bloodless cardiac surgery in Jehovah''s Witness patients can be performed with excellent outcomes in both elective and urgent situations. Mortality rates for isolated coronary artery bypass graft surgery and isolated aortic valve replacement are within the expected 95% confidence intervals of STS predicted mortality. [ABSTRACT FROM AUTHOR]

Background: Real-time three-dimensional (3D) echocardiography has the ability to construct quantitative models of the mitral valve (MV). Imaging and modeling algorithms rely on operator interpretation of raw images and may be subject to observer-dependent variability. We describe a comprehensive analysis technique to generate high-resolution 3D MV models and examine interoperator and intraoperator repeatability in humans. Methods: Patients with normal MVs were imaged using intraoperative transesophageal real-time 3D echocardiography. The annulus and leaflets were manually segmented using a TomTec Echo-View workstation. The resultant annular and leaflet point cloud was used to generate fully quantitative 3D MV models using custom Matlab algorithms. Eight images were subjected to analysis by two independent observers. Two sequential images were acquired for 6 patients and analyzed by the same observer. Each pair of annular tracings was compared with respect to conventional variables and by calculating the mean absolute distance between paired renderings. To compare leaflets, MV models were aligned so as to minimize their sum of squares difference, and their mean absolute difference was measured. Results: Mean absolute annular and leaflet distance was 2.4 ± 0.8 and 0.6 ± 0.2 mm for the interobserver and 1.5 ± 0.6 and 0.5 ± 0.2 mm for the intraobserver comparisons, respectively. There was less than 10% variation in annular variables between comparisons. Conclusions: These techniques generate high-resolution, quantitative 3D models of the MV and can be used consistently to image the human MV with very small interoperator and intraoperator variability. These data lay the framework for reliable and comprehensive noninvasive modeling of the normal and diseased MV. [Copyright &y& Elsevier]

Background: A comprehensive three-dimensional echocardiography based approach is applied to preoperative mitral valve (MV) analysis in patients with ischemic mitral regurgitation (IMR). This method is used to characterize the heterogeneous nature of the pathologic anatomy associated with IMR. Methods: Intraoperative real-time three-dimensional transesophageal echocardiograms of 18 patients with IMR (10 with anterior, 8 with inferior infarcts) and 17 patients with normal MV were analyzed. A customized image analysis protocol was used to assess global and regional determinants of annular size and shape, leaflet tethering and curvature, relative papillary muscle anatomy, and anatomic regurgitant orifice area. Results: Both mitral annular area and MV tenting volume were increased in the IMR group as compared with patients with normal MV (mitral annular area = 1,065 ± 59 mm2 versus 779 ± 44 mm2, p = 0.001; and MV tenting volume = 3,413 ± 403 mm3 versus 1,696 ± 200 mm3, p = 0.001, respectively). Within the IMR group, patients with anterior infarct had larger annuli (1,168 ± 99 mm2) and greater tenting volumes (4,260 ± 779 mm3 versus 2,735 ± 245 mm3, p = 0.06) than the inferior infarct subgroup. Papillary-annular distance was increased in the IMR group relative to normal; these distances were largest in patients with anterior infarcts. Whereas patients with normal MV had very consistent anatomic determinants, annular shape and leaflet tenting distribution in the IMR group were exceedingly variable. Mean anatomic regurgitant orifice area was 25.8 ± 3.0 mm2, and the number of discrete regurgitant orifices varied from 1 to 4. Conclusions: Application of custom analysis techniques to three-dimensional echocardiography images allows a quantitative and systematic analysis of the MV, and demonstrates the extreme variability in pathologic anatomy that occurs in patients with severe IMR. [Copyright &y& Elsevier]

Abstract: The heating systems are conventionally controlled by open-loop control systems because of the absence of practical methods for estimating average air temperature in the built environment. An inferential sensor model, based on adaptive neuro-fuzzy inference system modeling, for estimating the average air temperature in multi-zone space heating systems is developed. This modeling technique has the advantage of expert knowledge of fuzzy inference systems (FISs) and learning capability of artificial neural networks (ANNs). A hybrid learning algorithm, which combines the least-square method and the back-propagation algorithm, is used to identify the parameters of the network. This paper describes an adaptive network based inferential sensor that can be used to design closed-loop control for space heating systems. The research aims to improve the overall performance of heating systems, in terms of energy efficiency and thermal comfort. The average air temperature results estimated by using the developed model are strongly in agreement with the experimental results. [Copyright &y& Elsevier]

Purpose/objective(s): In contrast to radiographic imaging with implanted radio-opaque fiducials, the high soft tissue contrast and noninvasive nature of MRI are advantageous for real-time motion tracking of prostate motion. The purpose of this study is to investigate the feasibility of tracking the intrafraction prostate motion using an intensity-based template registration technique between real-time 2D cine and 3D MRI acquired during MR-guided Adaptative Radiation Therapy (MRgART).Materials/methods: The motion tracking algorithm includes two steps: (1) creating a template by rigidly registering a set of cine images with a 3D reference MRI, and (2) tracking the target motion by registering incoming (i.e., real-time) cine with the template with a known relationship to the 3D volume. The daily 3D T2 MRI and 2D T2/T1 bFFE real-time cine MRI acquired on a 1.5T MR-Linac during MRgART for 6 prostate cancer patients were selected to test the algorithm limits. The cine images were acquired with a temporal resolution of 0.2 s for a total duration of 9-11 minutes interleaved between coronal and sagittal orientations. A 2D template image set was generated in the coronal and sagittal planes using the cine data acquired during the first 20 s registered to the 3D volume using in-plane rigid-body image registration based on a region of interest defined by the prostate contour on 3D T2 MRI. Motion tracking of the prostate was performed by registering the rest of the 2D cine series with the corresponding template. Manually delineated contours on sampled cine frames were used as the ground truth. Tracking accuracy was defined as the standard deviation of the error (SDE) between the center of mass (CM) of the ground-truth and tracked motions in 1 min. Prostate drift was evaluated by tracking the CM shift with the algorithm every 8-9 s for 9-11 min.Results: The prostate tracking algorithm was qualitatively validated by visual assessment of 6 prostate cases. Overall, the tracking was found robust to implant-induced image artefacts in two cases, large change in bladder size in one case, and body motion in one other case. The tracking algorithm was also validated quantitatively on 2 cases for which ground truth contours were available and reliable. Mean SDE for the two cases was 0.45, 0.32, and 0.31 mm in superior-inferior, left-right, and anterior-posterior directions, respectively. A continuous motion drift of the prostate was observed over a 600 s period for one of these two cases and was accurately tracked by the technique.Conclusion: We have demonstrated the feasibility to track prostate motion based on real-time orthogonal cine MRI without implanting fiducials. With further investigation on more patients and following careful workflow, the real-time motion tracking technique may be implemented in MRgART to manage intrafraction motion.Author Disclosure: H. Jassar: None. A. Tai: None. X. Chen: None. T. Keiper: None. E.S. Paulson: Research Grant; Siemens Healthineers, Elekta Instruments AB.F. Lathuiliere: None. S. Bériault: None. D. Cooper: None. F. Hebert: None. L. Savard: None. S. Cloake: None. W.A. Hall: Research Grant; Elekta, National Cancer Institute, American Cancer Society. C.A. Lawton: None. A. Li: Research Grant; Elekta AB, Accuray Inc, Siemens Healthineers, Manteia Med. Honoraria; Elekta AB, Accuray Inc. Patent/License Fees/Copyright; Manteia Med. [ABSTRACT FROM AUTHOR]

The dental profession is considered at high potential risk of exposure and transmission of SARS-Cov-2. Thus, dentists should implement special safety measures in order to prevent any possible contamination during dental sessions and should be aware of the legal implications of their act in order to avoid malpractice leading them to be a causative agent of transmission of this virus. This paper aimed to provide a global review on COVID-19 preventive recommendations at dental clinics and discussed the legal values of such procedures, the dentist criminal and civil liability arising from transmitting this virus to a patient, the obligation of care under COVID-19 and the possible solution to this dilemma. The review concluded that dentists should follow all modern scientific procedures which are in their interest and in the interest of patients to maintain their safety and advised dentists to document all steps taken during the period of COVID-19 outbreak, because any undocumented action is considered not to have taken place, and they shall be bound by the burden of proof. [ABSTRACT FROM AUTHOR]

Misaligned deployment refers to eccentric flaring of the bare stent portion of the endograft that causes proximal device retroflexion resulting in suboptimal graft placement. A 71-year-old woman with 6.8-cm distal aortic arch aneurysm underwent hybrid repair with combination of open aortic arch debranching and subsequent thoracic endovascular aortic repair. During endograft deployment, misaligned opening occurred; this was corrected by using a balloon-assisted graft deployment. Follow up imaging continues to demonstrate complete aneurysm exclusion. Misaligned deployment is a clinical challenge; we hereby present a previously undescribed technique to accommodate this limitation of the current endograft technology. [Copyright &y& Elsevier]

There is growing concern over the impact of fatigue and long work hours on patient safety. Our objective was to determine the perioperative outcomes and hospital costs associated with starting nonemergent cardiac surgical cases after 3 pm. A retrospective analysis was performed on adult patients who underwent elective coronary artery bypass or valve surgery at our institution between July 2011 and March 2018. Cases were defined as "late start" if the incision time was after 3 pm. Postoperative outcomes, 30-day mortality, and total hospital costs were compared between propensity-matched samples of early-starting and late-starting cases. Of 2463 elective cases, 352 (14%) started after 3 pm. In propensity-matched samples, patients who had a late start demonstrated no difference in 30-day mortality (1% vs <1%; P =.10) or postoperative complications, such as prolonged ventilation (5% vs 7%; P =.37), renal failure (2% vs 1%), or stroke (2% vs 1%; P =.23) compared with patients who had an early start. A late start did not impact the median duration of ventilation (4 vs 5 hours; P =.72), intensive care unit (ICU) length of stay (26 vs 22 hours; P =.28), or postoperative length of stay (6 vs 7 days; P =.37). In addition, there were no significant differences in total hospital cost (P =.09), operating room cost (P =.22), or ICU cost (P =.05). We report no differences in perioperative outcomes, operative mortality, length of stay, or total hospital cost for elective cases that start after 3 pm. This may be attributable to the resources available at a large quaternary center regardless of time of day. Overview of the study design, which demonstrates equivalent outcomes and hospital costs for early- vs late-starting elective cardiac surgery cases. [ABSTRACT FROM AUTHOR]

We aimed to quantify incidence and operative risks associated with reoperative valve surgeries (RVS) in patients with drug-associated infective endocarditis in a multi-center setting. We formed a registry of patients with drug-associated infective endocarditis who underwent valve surgeries at 8 US centers between 2011 and 2017. Outcomes of first-time valve surgery (FVS) and RVS were compared. Multivariable logistic regression models related RVS to 30-day mortality. Poisson regression models were fitted to evaluate temporal trends in overall case volume and proportions of patients undergoing RVS. The cohort consisted of 925 patients with drug-associated infective endocarditis who underwent a valve surgery, of which 652 were FVS and 273 were RVS. Patients undergoing FVS had fewer comorbidities than those undergoing RVS. Overall case volume increased from 108 in 2012 to 229 cases in 2017 (P <.001). The proportion of redo valve cases increased from 19% in 2012 to 28% in 2017 (P <.001). The 30-day mortality in RVS was higher compared with FVS (8.1% vs 4.8%; P =.049). An increase in unadjusted mortality rates were observed as the number of prior cardiac surgeries increased, from 4.8% in FVS to 11.8% in ≥3 RVS. Multivariable model demonstrated that RVS was associated with an increased risk of 30-day mortality (odds ratio, 2.22; 95% confidence interval, 1.22-4.06; P =.010). An increasing proportion of valve surgery for drug-associated infective endocarditis is for RVS. Despite being young and harboring few comorbidities, the RVS cohort is still susceptible to increased risk of 30-day mortality compared with those undergoing FVS. [ABSTRACT FROM AUTHOR]

Prolonged cardiopulmonary bypass (CPB) is recognized as a risk factor for acute renal failure (ARF), but the dose effect of time on bypass is unknown. We therefore examined the risk of ARF associated with increasing CPB time stratified by preoperative renal function. A retrospective analysis was performed on 3889 patients undergoing cardiac surgery on CPB without circulatory arrest between 2011 and 2017 excluding those with a diagnosis of dialysis-dependent renal failure and those who had an intra-aortic balloon pump. Postoperative ARF was defined as a 3-fold increase in creatinine level, creatinine level > 4 mg/dL, or requirement for dialysis. A logistic regression model was built to identify predictors of ARF and to determine the probability of ARF. Postoperative ARF occurred in 72 patients (2%) overall. Of 100 patients with an estimated glomerular filtration rate <30 mL/min/1.73 m2, 22% developed ARF, of which 16 required dialysis. Thirty-day mortality was 31% for those with ARF compared with <1% for those without ARF (P <.01). Risk factors for ARF included obesity (odds ratio, 3.03; P <.01), increasing preoperative creatinine level (odds ratio, 4.21; P <.01), CPB time scaled by a factor of 10 minutes (odds ratio, 1.06; P =.04), and postoperative transfusion (odds ratio, 11.94; P <.01). The adjusted probability of ARF as a function of CPB time was determined and stratified by preoperative glomerular filtration rate. Increasing CPB duration is associated with postoperative ARF, particularly among those with preoperative renal impairment. For patients with an estimated glomerular filtration rate <30 mL/min/1.73 m2 the risk increases exponentially with time. Association between cardiopulmonary bypass and risk of postoperative acute renal failure. [ABSTRACT FROM AUTHOR]

Summary: Objective: The incidence of COM without cholesteatoma in Australian aboriginals is quoted as being between 25 and 47%. The incidence of cholesteatomatous OM is very low in comparison (between 1 and 3%). A comprehensive literature search found no studies offering an explanation for the large discrepancy between these two types of OM. We offer a theory to account for the disproportionate rates of the two types of OM together with an observational study on aboriginals with COM to substantiate our argument. Method/Results: The crux of our hypothesis centres on the anatomy of the posterior attic. We found that in a study of 40 aboriginal patients undergoing tympanoplasty with audiometric evidence of an intact ossicular chain that, after posterior tympanomeatal flap elevation, no part of the incudostapedial assembly was visible in 95% of cases denoting its location behind the posterior attic wall. Conclusion: We hypothesise that in aboriginal ears the resulting ‘crowding’ of the posterior attic by the incudostapedial assembly results in narrowing of the epitympanic space which compromises atticoantral drainage, thus leading to mucosal COM, however supporting the posterior-superior segment of the tympanic membrane, impeding the formation of a retraction pocket, and cholesteatoma formation migrating into the mastoid antrum. [Copyright &y& Elsevier]

Transcatheter technologies triggered the recent revision of the guidelines that progressively widened the indications for the treatment of aortic stenosis. On the surgical realm, a technology avoiding the need for sutures to anchor the prosthesis to the aortic annulus has been developed with the aim to reduce the duration of cardiopulmonary bypass and simplify the process of valve implantation. In addition to a transcatheter aortic valve replacement (TAVR)-like stent that exerts a radial force, these so-called "rapid deployment valves" or "sutureless valves" for aortic valve replacement also have cuffs to improve sealing and reduce the risk of paravalvular leak. Despite promising, the actual advantage of sutureless valves over traditional surgical procedures (surgical aortic valve replacement) or TAVR is still debated. This review summarizes the current comparative evidence reporting outcomes of "sutureless valves" for aortic valve replacement to TAVR and surgical aortic valve replacement in the treatment of aortic valve stenosis. • The comparative safety and efficacy of sutureless (SuAVR) vs conventional aortic valve replacement surgery is currently under investigation. • Potential candidates for SuAVR include those undergoing concomitant procedures, complex reoperations in patients with frail aortic root tissue, minimally invasive aortic valve replacement procedures, and high-risk patients for whom TAVR is not suitable. • The Heart Team should participate in shared decision making with patients in the selection of valve replacement modality for aortic stenosis. [ABSTRACT FROM AUTHOR]

Ischemic stroke due to large-vessel occlusion (LVO) is a complication after cardiothoracic surgery (CTS). Recently published endovascular stroke trials have major implications for treating LVO strokes; we evaluated our experience in patients undergoing CTS. Our prospective institutional CTS database was reviewed between July 2013 and April 2018 for ischemic strokes. Patients with LVO were identified and their course and outcomes analyzed. A total of 5947 patients were reviewed; 148 (2.48%) had a cerebrovascular complication; 92.5% were ischemic. Of these 10.9% had an LVO. Prolonged aortic crossclamp was associated with LVO (odds ratio, 1.012 for every minute of prolonged aortic crossclamp time; confidence interval, 1.001-1.023) and remained significant in patients with ejection fraction >45%; prolonged cardiac bypass time was only associated with LVO in patients with ejection fraction >45% (odds ratio, 1.012 for every minute of prolonged cardiac bypass time; confidence interval, 1.003-1.021). Patients fell into 2 categories: detection of neurologic deficit in the stable postoperative patient or detection of deficit on emergence from anesthesia. Seven patients met criteria for emergent revascularization, with median National Institutes of Health Stroke Scale score 15, and shorter times from last seen well to deficit detection compared with patients not meeting criteria (P =.032). Median National Institutes of Health Stroke Scale day 7 score improved to 5. There was a trend toward better modified Rankin Scale scores at 3 months in patients who underwent thrombectomy. LVO complicates a small proportion of patients after CTS and may be more likely with prolonged aortic crossclamp and cardiac bypass times. Both early and late window endovascular stroke treatment has the potential to positively modify the complication profile of CTS. Greater awareness of this treatment option is needed. [ABSTRACT FROM AUTHOR]

Complex adult coarctations associated with arch hypoplasia and aneurysms require a range of surgical approaches depending upon anatomy. Extraanatomic bypass is an important strategy that enables the surgeon to avoid the risks of extensive dissection/mobilization. Extraanatomic bypass can be accomplished from the ascending to lower descending thoracic aorta via an intrapericardial route lateral to the right atrium and posterior to the inferior vena cava; however, this approach incompletely addresses post-stenotic aneurysmal disease. In the case of complex coarctation with aneurysm, we prefer an alternate approach to exclude the aneurysm, routing the bypass graft anterior to the phrenic nerve to the upper descending thoracic aorta. [ABSTRACT FROM AUTHOR]