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Background The coronavirus disease 2019 (COVID‐19) pandemic has had an unprecedented impact on health care and cardiac surgery. We report cardiac surgeons' concerns, perceptions, and responses during the COVID‐19 pandemic. Methods A detailed survey was sent to recruit participating adult cardiac surgery centers in North America. Data regarding cardiac surgeons' perceptions and changes in practice were analyzed. Results Our study comprises 67 institutions with diverse geographic distribution across North America. Nurses were most likely to be redeployed (88%), followed by advanced care practitioners (69%), trainees (28%), and surgeons (25%). Examining surgeon concerns in regard to COVID‐19, they were most worried with exposing their family to COVID‐19 (81%), followed by contracting COVID‐19 (68%), running out of personal protective equipment (PPE) (28%), and hospital resources (28%). In terms of PPE conservation strategies among users of N95 respirators, nearly half were recycling via decontamination with ultraviolet light (49%), followed by sterilization with heat (13%) and at home or with other modalities (13%). Reuse of N95 respirators for 1 day (22%), 1 week (21%) or 1 month (6%) was reported. There were differences in adoption of methods to conserve N95 respirators based on institutional pandemic phase and COVID‐19 burden, with higher COVID‐19 burden institutions more likely to resort to PPE conservation strategies. Conclusions The present study demonstrates the impact of COVID‐19 on North American cardiac surgeons. Our study should stimulate further discussions to identify optimal solutions to improve workforce preparedness for subsequent surges, as well as facilitate the navigation of future healthcare crises.

Objectives The prosthesis type for multiple valve surgery (replacement of two or more diseased native or prosthetic valves, replacement of two diseased valves with repair/reconstruction of a third, or replacement of a single diseased valve with repair/reconstruction of a second valve) remains inadequately evaluated. The clinical performance of multiple valve surgery with bioprostheses (BP) and mechanical prostheses (MP) was assessed to compare patient survival and composites of valve-related complications. Methods Between 1975 and 2000, 1245 patients had multiple valve surgery (BP 785, mean age 62.0 ± 14.7 years; and MP 460, mean age 56.9 ± 12.9 years). There were 1712 procedures performed [BP 969(56.6%) and MP 743(43.4%). Concomitant coronary artery bypass (conCABG) was BP 206(21.3%) and MP 105(14.1%) (p = 0.0002). The cumulative follow-up was BP 5131 years and MP 3364 years. Independent predictors were determined for mortality, valve-related complications and composites of complications. Results Unadjusted patient survival at 12 years was BP 52.1 ± 2.1% and MP 54.8 ± 4.6% (p = 0.1127), while the age adjusted survival was BP 48.7 ± 2.3% and MP 54.4 ± 5.0%. The predictors of overall mortality were age [Hazard Ratio (HR) 1.051, p MP) (2.61, p = 0.001), age (HR 1.032, p = 0.0005) and previous valve (HR 12.61, p BP) (HR 0.32, p Conclusions Overall survival (age adjusted) is differentiated by valve type over 10 and 12 years and valve-related mortality and valve-related reoperation favours the use of mechanical prostheses, overall for multiple valve surgery.

Extra-corporeal life support (ECLS) is a life-saving intervention for patients with hypothermia induced cardiac arrest or severe cardiovascular instability. However, its application is highly variable due to a paucity of data in the literature to guide practice. Current guidelines and recommendations are based on expert opinion, single case reports, and small case series. Combining all of the published data in a patient-level analysis can provide a robust assessment of the influence of patient characteristics on survival with ECLS.To develop a prediction model of survival with good neurologic outcome for accidental hypothermia treated with ECLS.Electronic searches of PubMed, EMBASE, CINAHL were conducted with a hand search of reference lists and major surgical and critical care conference abstracts. Studies had to report the use of ECLS configured with a circuit, blood pump and oxygenator with an integrated heat exchanger. Randomized and observational studies were eligible for inclusion. Non-human, non-English and review manuscripts were deemed ineligible. Study authors were requested to submit patient level data when aggregate or incomplete individual patient data was provided in a study. Survival with good neurologic outcome was categorized for patients to last follow-up based on the reported scores on the Cerebral Performance Category (1 or 2), Glasgow Outcome Scale (4 or 5) and Pediatric Overall Performance Category (1 or 2). A one-stage, individual patient data meta-analysis was performed with a mixed-effects multi-level logistic regression model reporting odds ratio (OR) with a 95% confidence interval (CI).Data from 44 observational studies and 40 case reports (n = 658) were combined and analyzed to identify independent predictors of survival with good neurologic outcome. The survival rate with good neurologic outcome of the entire cohort was 40.3% (265 of 658). ECLS rewarming rate (OR: 0.93; 95% CI: 0.88, 0.98; p = .007), female gender (OR: 2.78; 95% CI: 1.69, 4.58; p 0.001), asphyxiation (OR: 0.19; 95% CI: 0.11, 0.35; p 0.001) and serum potassium (OR: 0.62; 95% CI: 0.53, 0.73; p 0.001) were associated with survival with a good neurologic outcome. The logistic regression model demonstrated excellent discrimination (c-statistic: 0.849; 95% CI: 0.823, 0.875).The use of extracorporeal life support in the treatment of hypothermic cardiac arrest provides a favourable chance of survival with good neurologic outcome. When used in a weighted scoring system, asphyxiation, serum potassium and gender can help clinicians prognosticate the benefit of resuscitating hypothermic patients with ECLS.

The Mosaic bioprosthesis is a third-generation stented porcine bioprosthesis. This study was performed to evaluate long-term survival and durability associated with this device.A total of 1,029 patients (797 aortic valve replacements, 232 mitral valve replacements) previously enrolled at 6 centers as part of the original regulatory study were included. We evaluated freedom from death, valve-related reoperation, and explant due to structural valve deterioration (SVD), and compared these outcomes by age (60 and ≥60 years) at the time of implant.Cumulative follow-up was 7021.2 patient-years in the aortic cohort and 1969.5 patient-years in the mitral cohort. Mean age was 69.5 ± 8.6 and 67.9 ± 10.5 years; 66% and 48% were male, respectively. In the aortic cohort at 17 years, freedom from death was 54.0% in patients younger than 60 years and 24.0% in patients aged 60 years and older (p0.01); freedom from reoperation was 36.4% and 81.2%, respectively (p0.01); and freedom from explant due to SVD was 47.5% and 89.1% (p0.01). At 16 years in the mitral cohort, freedom from death was 67.6% and 20.6% (p0.01); freedom from reoperation was 51.3% versus 77.9% (p = 0.04); and freedom from explant due to SVD was 65.2% versus 83.8% (p = 0.23).This study demonstrates acceptable long-term rates of death, reoperation, and explant due to SVD with the Mosaic bioprosthesis implanted in either the aortic or mitral position. Freedom from explant due to SVD was lower in patients younger than 60 years in the aortic cohort at 17 years, but it was not significantly different between patients younger than 60 years or 60 years and older in the mitral cohort at 16 years.

Objective The coronavirus disease 2019 (COVID-19) pandemic has resulted in an increase in hospital resource utilization and the need to defer nonurgent cardiac surgery procedures. The present study aims to report the regional variations of North American adult cardiac surgical case volume and case mix through the first wave of the COVID-19 pandemic. Methods A survey was sent to recruit participating adult cardiac surgery centers in North America. Data in regard to changes in institutional and regional cardiac surgical case volume and mix were analyzed. Results Our study comprises 67 adult cardiac surgery institutions with diverse geographic distribution across North America, representing annualized case volumes of 60,452 in 2019. Nonurgent surgery was stopped during the month of March 2020 in the majority of centers (96%), resulting in a decline to 45% of baseline with significant regional variation. Hospitals with a high burden of hospitalized patients with COVID-19 demonstrated similar trends of decline in total volume as centers in low burden areas. As a proportion of total surgical volume, there was a relative increase of coronary artery bypass grafting surgery (high +7.2% vs low +4.2%, P = .550), extracorporeal membrane oxygenation (high +2.5% vs low 0.4%, P = .328), and heart transplantation (high +2.7% vs low 0.4%, P = .090), and decline in valvular cases (high –7.6% vs low –2.6%, P = .195). Conclusions The present study demonstrates the impact of COVID-19 on North American cardiac surgery institutions as well as helps associate region and COVID-19 burden with the impact on cardiac surgery volumes and case mix.

The St. Jude Medical bileaflet mechanical heart valve was approved by the Food and Drug Administration in late 1970s. The basic idea for the design of the valve is simply two semicircular flat plates pivoting on hinges. The overall performance of St. Jude Medical valves such as blood flow being central, the leaflets opening completely, and the pressure drop across the valve being trivial is satisfactory. St. Jude Medical valves provide an improved hemodynamics compared to the other mechanical heart valve models; however, their non-physiological hemodynamics which may lead to red blood cells lysis and thrombogenicity still remains a major issue. In this study, we hypothesize that applying ovality to the housing might improve their hemodynamics significantly which is based on the fact that the native annulus is oval by nature. A quick but precise numerical model based on the finite strip method was developed by which the regurgitation flow volume and velocity of the proposed design were assessed in the closing phase. The results are satisfactory and an improved hemodynamics is observed. The proposed design can be considered for further numerical and experimental studies and shows promise and merits further development.

In this study, a polymeric human aortic root made of hydrogel-based biomaterials is proposed. To design the geometry of the root, an advanced surfacing technique based on the de Casteljau method (for developing Bezier surfaces) was applied. The three-dimensional geometry was developed using two-dimensional images obtained by the radial dissection of an adult human aortic root. The biomaterial used for the aortic valve was a biocompatible hydrogel made of polyvinyl alcohol (PVA) reinforced by bacterial cellulose (BC) natural nanofibers in a combination of 15% PVA and 0.5% BC, by weight fraction. The biomaterial used for the root was only 10% PVA. The tensile properties of the synthesized PVA-BC that were measured are close to those of the human aortic valve leaflet tissue in the two principle directions, radial and circumferential. Also, we obtained a close match of the stress–strain curves for the aorta in the circumferential and axial directions and anisotropic 10% PVA with 75% initial strain after cycle 3. A cavity mold was designed and manufactured and the proposed polymeric valve was then fabricated. An extensive finite element analysis was performed in order to optimize the final product. The proposed model can be further considered for clinical applications or may be used for tissue engineering applications.

Transcatheter heart valves are promising for high-risk patients. Generally, their leaflets are made of pericardium stented in a Nitinol basket. Despite their relative success, they are associated with significant complications such as valve migration, implantation risks, stroke, coronary obstruction, myocardial infraction, acute kidney injury (which all are due to the release of detached solid calcific pieces in to the blood stream) and expected issues existing with tissue valves such as leaflet calcification. This study is an attempt to fabricate the first ever polymeric percutaneous valves made of cryogel following the geometry and mechanical properties of porcine aortic valve to address some of the above-mentioned shortcomings. A novel, one-piece, tricuspid percutaneous valve, consisting of leaflets made entirely from the hydrogel, polyvinyl alcohol cryogel reinforced by bacterial cellulose natural nanocomposite, attached to a Nitinol basket was developed and demonstrated. Following the natural geometry of the valve, a novel approach was applied based on the revolution about an axis of a hyperboloid shape. The geometry was modified based on avoiding sharp warpage of leaflets and removal of the central opening orifice area of the valve when valve is fully closed using the finite element analysis. The modified geometry was replaced by a cloud of (control) points and was essentially converted to Bezier surfaces for further adjustment. A cavity mold was then designed and fabricated to form the valve. The fabricated valve was sewn into the Nitinol basket which is covered by Dacron cloth. The models presented in this study merit further development and revisions for both aortic and mitral positions.

Importance Although the long-term survival advantage of multiple arterial grafting (MAG) vs the standard use of left internal thoracic artery (LITA) supplemented by saphenous vein grafts (LITA+SVG) has been demonstrated in several observational studies, to our knowledge its safety and other long-term clinical benefits in a large, population-based cohort are unknown. Objective To compare the safety and long-term outcomes of MAG vs LITA+SVG among overall and selected subgroups of patients. Design, Setting, and Participants In this population-based observational study, we included 20 076 adult patients with triple-vessel or left-main disease who underwent primary isolated coronary artery bypass grafting (MAG, n = 5580; LITA+SVG, n = 14 496) in the province of British Columbia, Canada, from January 2000 to December 2014, with follow-up to December 2015. We performed propensity-score analyses by weighting and matching and multivariable Cox regression to minimize treatment selection bias. Exposures Multiple arterial grafting or LITA+SVG. Main Outcomes and Measures Mortality, repeated revascularization, myocardial infarction, heart failure, and stroke. Results Of 5580 participants who underwent MAG, 586 (11%) were women and the mean (SD) age was 60 (8.7) years. Of 14 496 participants who underwent LITA+SVG, 2803 (19%) were women and the mean (SD) age was 68 (8.9) years. The median (interquartile range) follow-up time was 9.1 (5.1-12.6) years and 8.1 (4.5-11.7) years for the groups receiving MAG and LITA+SVG, respectively. Compared with LITA+SVG, MAG was associated with reduced mortality rates (hazard ratio [HR], 0.79; 95% CI, 0.72-0.87) and repeated revascularization rates (HR, 0.74; 95% CI, 0.66-0.84) in 15-year follow-up and reduced incidences of myocardial infarction (HR, 0.63; 95% CI, 0.47-0.85) and heart failure (HR, 0.79; 95% CI, 0.64-0.98) in 7-year follow-up. The long-term benefits were coherent by all 3 statistical methods and persisted among patient subgroups with diabetes, obesity, moderately impaired ejection fraction, chronic obstructive pulmonary disease, peripheral vascular disease, or renal disease. Multiple arterial grafting was not associated with increased morbidity or mortality rates at 30 days overall or within patient subgroups. Conclusions and Relevance Compared with LITA+SVG, MAG is associated with reduced mortality, repeated revascularization, myocardial infarction, and heart failure among patients with multivessel disease who are undergoing coronary artery bypass grafting without increased mortality or other adverse events at 30 days. The long-term benefits consistently observed across multiple outcomes and subgroups support the consideration of MAG for a broader spectrum of patients who are undergoing coronary artery bypass grafting in routine practice.

Background: Regional variation in the utilization of health services is a well-documented phenomenon in health care with numerous studies reporting substantial and unexplained variations in coronary revascularization. In the Canadian province of British Columbia (BC), five cardiac centers provide coronary revascularization services. In 2011 Cardiac Services BC (CSBC) undertook a study that identified substantial regional variation in coronary revascularization that could not be explained by patient characteristics or risk factors. Following this initial project, CSBC launched an initiative to help better understand the regional variations and possibly devise and implement strategies to reduce them. Methods: Using Lean methodology, we are mapping the key processes of care for ACS patients across BC (initially excluding emergent STEMI and cardiogenic shock) at each cardiac centre. The ACS patient journey will be mapped from admission to discharge through several key decision points that determine whether they will continue through to diagnostic catheterization and revascularization or to be medically managed alone. The key decision points are: 1. Decision to refer to diagnostic catheterization and subsequent transfer if necessary. 2. Decision to continue to a revascularization procedure (PCI or CABG) after diagnostic catheterization. The map will summarized these key decision points using multiple sources of data: 1. Flow and patient volumes into and out of each of these decision 2. Times between decision points and key care processes 3. Clinical influencers (ex: standard orders, best practice, established patterns of referral, and consultations) and non-clinical influencers (ex: resource capacity, transportation) that are considered at each decision point (process mapping and interview data). Discussion: BC is attempting to reduce unexplained variation in coronary revascularization using the Lean methodology to take a systematic approach to the analysis of the process of ACS care across the province. Involving physicians and point of care staff in the detailed mapping process has proven to be a significant step in engaging key stakeholders in the project by allowing input into the process of describing the factors affecting variation of practice at each site. The next step is to convene provincially to determine where to improve standardized practice in order to improve patient outcomes at key points along the value stream.

Developing cardiac surgical skills and experience takes years of practice. Cardiac trainees need to develop technical proficiency in order to enhance quality of care and patient safety. Simulation-based models are common resources for teaching procedural skills in both undergraduate and postgraduate medical education. Suitable and accessible educational platforms can play a progressively important role in the training process for young surgeons in the area of cardiac surgery. Coronary artery bypass graft (CABG) surgery consists of a wide range of pathologic anatomies and surgical techniques. In this paper we introduce a novel, synthetic, biomimetic platform that allows for the realistic practice of the CABG surgery. The prototype uses a polyvinyl alcohol hydrogel which has been designed to mimic the geometric properties of vasculature. The proposed models look and feel like human tissue and possess somewhat consistent mechanical properties. In this study, we apply the platform to simulate a case of autogenous saphenous vein bypass grafting of a patient. An autogenous saphenous vein graft is placed from the aorta to the left anterior descending coronary artery. The standard procedures of the coronary artery bypass surgery were successfully simulated. Using the proposed technology, other complicated surgeries such as end to end, side to end, and sequential anastomoses can be simulated such that these models lend themselves very well to various types of anastomoses.

Despite successful implantation of St. Jude Medical bileaflet mechanical heart valves, red blood cell lysis and thrombogenic complications associated with these types of valves are yet to be addressed. In our previous study, we proposed an elliptic housing where 10% ovality was applied to the housing of St. Jude Medical valves. Our preliminary results suggested that the overall hemodynamic performance of St. Jude Medical valves improved in both the closing and opening phases. In this study, we evaluated the hemodynamics around the leaflets in the opening phase using a more sophisticated computational platform, computational fluid dynamics. Results suggested both lower shear stress and wall shear stress values and an overall improved hemodynamic performance in the proposed design. This improvement is characterized by lower values of shear stress and wall shear stress in the regions downstream of the leaflets, lower pressure drop across the valve and smaller recirculation zones in the sinuses areas. The proposed design may open a new chapter in the concept of design and hemodynamic improvement of the next generation of mechanical heart valves.

Background: Guidelines for timing of elective bypass surgery were established by expert opinion; yet, there is little evidence to support the recommended target times. Objectives: To estimate the effect of timing of the procedure on in-hospital mortality by comparing groups of patients that differ in the duration of time between decision to operate and performed procedure. Research Design: We used a population-based registry to identify patients who underwent surgical coronary revascularization and their hospital discharge summaries to identify in-hospital death. Subjects: We studied 9593 patients who underwent surgical revascularization between 1992 and 2006 after registration on a wait list for first-time isolated coronary artery bypass grafting on an elective basis. Measures: The outcome was postoperative in-hospital death. The study variable was the timing of surgery, categorized as short, prolonged, and excessive delays according to the guidelines. Methods: The probability of in-hospital death in relation to timing of surgery was modeled by logistic regression that included a precalculated risk score for in-hospital death, with weighting observations by inverse propensity scores for the 3 surgery timing groups. Results: In-hospital death among patients with short delays was one third as likely as among those with excessive delays: adjusted odds ratio=0.32 (95% confidence interval 0.20–0.51). The protective effect was smaller and not significant for patients with prolonged delays; odds ratio=0.78 (95% confidence interval, 0.38–1.63). Conclusions: Our findings suggest a survival benefit from performing elective surgical revascularization within the time frame recommended by the stricter of the 2 guidelines. Our results have implications for health systems that provide universal coverage and that budget the annual number of procedures.

Summary Objective Patients with diabetes experience increased cardiovascular complications after cardiac surgery. Hyperglycaemia predicts increased mortality after myocardial infarction and may influence cardiovascular risk in humans. Impaired prosurvival phosphatase and tensin homologue on chromosome 10 (PTEN)-Akt signalling could be an important feature of the diabetic heart rendering it resistant to preconditioning. This study was designed to evaluate for differences and relationships of myocardial PTEN-Akt-related signalling and baseline glycaemic control marker in type 2 diabetic and nondiabetic patients undergoing coronary artery bypass surgery. Methods Right atrial biopsies and coronary sinus blood were obtained from 18 type 2 diabetic and 18 nondiabetic patients intraoperatively. Expression and phosphorylation of Akt, endothelial nitric oxide synthase (eNOS), Bcl-2 and PTEN were evaluated by Western blot. Plasma 15-F2t-isoprostane concentrations were evaluated by liquid chromatography-mass spectrometry. Results PTEN expression and 15-F2t-isoprostane concentrations were significantly higher in diabetic patients. Increased fasting blood glucose levels correlated with increased coronary sinus plasma 15-F2t-isoprostane concentrations. Increased cardiac 15-F2t-isoprostane generation was highly correlated with myocardial PTEN expression. Bcl-2 expression and eNOS phosphorylation were significantly lower in diabetic compared with nondiabetic patients. Akt phosphorylation tended to be lower in diabetic patients; however, this tendency failed to reach statistical significance. Conclusion The current results suggest that prosurvival PTEN-Akt signalling is impaired in the diseased diabetic myocardium. Hyperglycaemia and increased oxidative stress may contribute to this phenomenon. These findings strengthen the understanding of the underlying biologic mechanisms of cardiac injury in diabetic patients, which could facilitate development of new treatments to prevent cardiovascular complications in this high-risk population.

Background The effect of prosthesis-patient mismatch on long-term survival after mitral valve replacement (MVR) has received limited attention. This study was performed to determine the predictors of mortality after MVR and influence of prosthesis-patient mismatch on survival. Methods Contemporary mechanical prostheses and bioprostheses were implanted in 2,440 patients with MVR between 1982 and 2002. The mean age was 63.9 ± 12.1 years and the mean follow-up was 6.1 ± 4.6 years, a total of 14,797.7 years of follow-up. Prosthesis-patient mismatch was classified by effective orifice area index categories: normal, greater than 1.2 cm 2 /m 2 (345, 14.2%); mild-to-moderate, equal to or less than 1.2 to greater than 0.9 cm 2 /m 2 (1,696, 69.5%); and severe, equal to or less than 0.9 cm 2 /m 2 (399, 16.4%). Results The predictors of overall mortality were age, age categorization, New York Heart Association III-IV, concomitant coronary artery bypass, ventricular dysfunction, prosthesis type, body mass index, and pulmonary hypertension. All categories of effective orifice area indices (EOAIs) were not predictive of overall mortality, late mortality, or early mortality. The 15-year survival was not differentiated by EOAI categories; 32.0 ± 4.4%, 32.9 ± 2.1%, and 36.6 ± 6.3%, respectively, for the three categories. Pulmonary hypertension influenced mortality by EOAI categories; normal versus mild-to-moderate ( p = 0.0317) and normal versus severe ( p = 0.0320). The EOAI was not an independent predictor of mortality in the consideration of patients with pulmonary hypertension but there is an interaction between pulmonary hypertension and mild-to-moderate ( p = 0.023) and severe ( p = 0.031) EOAI. Conclusion Prosthesis-patient mismatch is not a predictor of overall mortality to 15 years after MVR regardless of the category of effective orifice area index. The preoperative variable, pulmonary hypertension, influences overall mortality in the presence of mild-to-moderate and severe prosthesis-patient mismatch in the survival analysis.

When access to elective surgery is rationed by wait lists, patients requiring coronary artery bypass grafting may have to wait after a decision to operate has been made. The current literature suggests that a long wait for planned surgical revascularization may lead to worsening of symptoms, deterioration in the patient's condition and a less favorable clinical outcome; it may also increase the probability of preoperative death and unplanned emergency admission. Yet there has been little evidence generated by appropriate statistical methodology that bears on the health effects of a delay in undergoing the operation. In this article, we present three potential approaches for summarizing wait-list data. We also discuss the utility of each method for determining the point at which a delay in waiting for coronary artery bypass surgery becomes too long, from the perspectives of hospital managers, surgeons and patients.

Background Consensus reports over the past 10 years from the United States, Europe, United Kingdom, and Canada have not provided consistent guidelines for antithrombotic therapy of aortic valve bioprostheses for the three-month period after surgery. This study was conducted to determine if antithrombotic therapy was protective against TE with aortic bioprostheses 30 days or less after aortic valve replacement (AVR). Methods From 1994 to 2000, 1,372 patients implanted with three currently marketed aortic bioprostheses, Medtronic Mosaic (Medtronic, Inc, Minneapolis, MN) (415 patients), Carpentier-Edwards SAV (462), and Carpentier-Edwards PERIMOUNT (495) (Edwards Lifesciences, Irvine, CA), with a mean age of greater than 70 years were evaluated. Patient populations were comparable, inclusive of concomitant coronary artery bypass grafting (CABG) for the overall populations and for patients greater than 70 years. Results There were 37 thromboembolic (TE) events: major TE, 14; reversible ischemic neurologic deficit (RIND), 12; and minor TE, 11. There were 4 TE deaths. Multivariate (stepwise logistic regression) analysis revealed no predictive risk factors for overall TE. For the combination of major TE plus RIND there were two predictive risk factors with analysis of 12 risk variables: preoperative cerebrovascular accident (odds ratio [OR] 4.45, 95% confidence interval [CI] 1.17 to 16.87, p = 0.028); and concomitant CABG (OR 3.19, 95% CI 1.16 to 8.76, p = 0.025). Neither anticoagulant nor antiplatelet therapies gave significant protection. Conclusions There does not appear to be an indication for routine antithrombotic management. The study supports the potential use of antithrombotic therapy for comorbidities of preoperative cerebrovascular accident and concomitant CABG but not atrial fibrillation, left ventricular dysfunction, or elderly age greater than 70 years. Vascular burden and advanced age are likely contributing factors to these independent predictors. There may still be a need for, or at least consideration of, a randomized trial for AVR with bioprostheses.

Background: Regional variation in the utilization of health services is a well-documented phenomenon in health care with numerous studies reporting substantial and unexplained variations in coronary revascularization. In the Canadian province of British Columbia (BC), five cardiac centers provide coronary revascularization services. In 2011 Cardiac Services BC (CSBC) undertook a study that identified substantial regional variation in coronary revascularization that could not be explained by patient characteristics or risk factors. Following this initial project, CSBC launched an initiative to help better understand the regional variations and possibly devise and implement strategies to reduce them. To get a better understanding of the different processes of care/utilization, one of the approaches used is the application of Lean methodology to the care of acute coronary syndrome (ACS) patients. Methods: Lean methodology is being applied to the patient journey of ACS patients. At each revascularization center Value Steam Maps process maps (VSM) are being prepared through a series of meetings with support, frontline, administrative and clinical staff (see attached example). For each VSM the goal is to identify key decision points in the process of care for ACS patients and to drill down on (Root Cause Analysis) on the decision making environment and criteria used to determine the utilization of coronary revascularization services. Once VSM have been completed they will be compared across sites for similarities and differences. The differences in decision making will then be assessed to determine their effect on variation in utilization across the centers. Discussion: BC is attempting to reduce unexplained variation in coronary revascularization using the Lean methodology to take a systematic approach to the analysis of the process of ACS care across the province. The next step will be to determine to what extent it is possible to standardize decision making at the key decision points across the HAs. Standardization will be achieved through a mix of best practices, evidence and application of guidelines. While the undertaking is still in the early stages it is expected that it will lead to, at the very least, ACS patients receiving the same care regardless of where they receive their care in BC.

A powerful alternative means to study the hemodynamics of bileaflet mechanical heart valves is the computational fluid dynamics method. It is well recognized that computational fluid dynamics allows reliable physiological blood flow simulation and measurements of flow parameters. To date, in almost all of the modeling studies on the hemodynamics of bileaflet mechanical heart valves, a velocity (mass flow)-based boundary condition and an axisymmetric geometry for the aortic root have been assigned, which, to some extent, are erroneous. Also, there have been contradictory reports of the profile of velocity in downstream of leaflets, that is, in some studies, it is suggested that the maximum blood velocity occurs in the lateral orifice, and in some other studies, it is postulated that the maximum velocities in the main and lateral orifices are identical. The reported values for the peak velocities range from 1 to 3 m/s, which highly depend on the model assumptions. The objective of this study is to demonstrate the importance of the exact anatomical model of the aortic root and the realistic boundary conditions in the hemodynamics of the bileaflet mechanical heart valves. The model considered in this study is based on the St Jude Medical valve in a novel modeling platform. Through a more realistic geometrical model for the aortic root and the St Jude Medical valve, we have developed a new set of boundary conditions in order to be used for the assessment of the hemodynamics of aortic bileaflet mechanical heart valves. The results of this study are significant for the design improvement of conventional bileaflet mechanical heart valves and for the design of the next generation of prosthetic valves.

To date, to the best of the authors’ knowledge, in almost all of the studies performed around the hemodynamics of bileaflet mechanical heart valves, a heart rate of 70–72 beats/min has been considered. In fact, the heart rate of ~72 beats/min does not represent the entire normal physiological conditions under which the aortic or prosthetic valves function. The heart rates of 120 or 50 beats/min may lead to hemodynamic complications, such as plaque formation and/or thromboembolism in patients. In this study, the hemodynamic performance of the bileaflet mechanical heart valves in a wide range of normal and physiological heart rates, that is, 60–150 beats/min, was studied in the opening phase. The model considered in this study was a St. Jude Medical bileaflet mechanical heart valve with the inner diameter of 27 mm in the aortic position. The hemodynamics of the native valve and the St. Jude Medical valve were studied in a variety of heart rates in the opening phase and the results were carefully compared. The results indicate that peak values of the velocity profile downstream of the valve increase as heart rate increases, as well as the location of the maximum velocity changes with heart rate in the St. Jude Medical valve model. Also, the maximum values of shear stress and wall shear stresses downstream of the valve are proportional to heart rate in both models. Interestingly, the maximum shear stress and wall shear stress values in both models are in the same range when heart rate is 90 beats/min (up to ~40% growth compared to that of the native valve). The findings of this study may be of importance in the hemodynamic performance of bileaflet mechanical heart valves. They may also play an important role in design improvement of conventional prosthetic heart valves and the design of the next generation of prosthetic valves, such as percutaneous valves.

ObjectiveThis study was conducted to compare the composites of valve-related complications, namely reoperation, morbidity (defined as permanent neurologic or other functional impairment), and mortality, between bioprostheses and mechanical prostheses for aortic valve replacement.MethodsBetween 1982 and 1998, 2195 bioprostheses were implanted in 2179 patients and 980 mechanical prostheses were implanted in 883 patients. Total follow-up was 16,442 years and 5740 years for bioprostheses and mechanical prostheses, respectively. Eight variables were considered as predictors of risk for the composites of valve-related complications.ResultsLinearized rates for valve-related reoperation were 1.3%/patient-year and 0.3%/patient-year for bioprostheses and mechanical prostheses (P < .001), respectively. All age groups were differentiated, except >70 years. Valve-related morbidity was differentiated for all age groups and overall, for bioprostheses and mechanical protheses, was 0.4 %/patient-year and 2.1%/patient-year, respectively (P < .001). Overall valve-related mortality was 1.0%/patient-year for bioprostheses and 0.7%/patient-year for mechanical prostheses (P = .018). Age and valve-type were predictive risk factors for reoperation and morbidity, whereas age alone was predictive of mortality. Actual freedom from valve-related reoperation favored mechanical prostheses for all age groups, except 61-70 years and >70 years. Actual freedom from valve-related morbidity favored bioprostheses in all age groups, except ≤40 years. Actual freedom from valve-related mortality was undifferentiated in patients 51-60, 61-70, and >70 years.ConclusionNo differences were observed in valve-related reoperation and mortality in patients >60 years. Comparative evaluation gives high priority for bioprostheses in patients >60 years based on improved morbidity profile. This evaluation extends this center’s recommendation for bioprostheses in aortic valve replacement to include patients >60 years.

The second-generation Carpentier-Edwards bioprostheses, the supra-annular porcine valve and the PERIMOUNT pericardial valve, have been evaluated longitudinally for several years. This study compared clinical performance over 15 years. Aortic valve replacement was performed with a supra-annular porcine valve in 1,823 patients (group 1) aged 19–89 years (mean, 68.9 ± 10.9 years) and with a PERIMOUNT pericardial bioprosthesis in 1,430 patients (group 2) aged 16–90 years (mean, 69.5 ± 10.4 years). The groups were similar except for concomitant coronary artery bypass in 43% of group 1 and 18% of group 2 ( p < 0.001). Overall survival at 15 years was 29.3% ± 1.5% for group 1 and 35.2% ± 3.1% for group 2 ( p = 0.0009). The actual freedom from valve-related mortality was 88.5% ± 0.9% for group 1 and 84.9% ± 1.7% for group 2. The actual freedom from structural valve deterioration at 15 years was similar overall, and for patients aged > 60 years, between the groups, but was dissimilar (group 2 > group 1) for age ≤ 60 years. The predictors of structural valve deterioration were valve type (group 1 > group 2), sex (male > female), age, and concomitant coronary artery bypass. Both bioprostheses provided satisfactory clinical performance at 15 years after aortic valve replacement.

In this review, the anatomy and structure of the aortic valve and its prostheses are comprehensively discussed. Cardiac anatomy and function, human heart valves and their prostheses are also extensively discussed. The current

Background Recipients of heart, lung, and kidney transplants have impaired peak exercise performance (peak Vo2 40% to 60% predicted, reduced anaerobic threshold [AT]) without evidence of ventilatory or cardiac limitations. The aim of this study was to determine whether similar exercise impairment occurs in liver transplant recipients. Methods We studied eight healthy liver transplant recipients (age 42+/-9 [SD] years, 6 male, 31+/-13 months posttransplant). Immunosuppression included FK506 or cyclosporine, azathioprine or mycophenolate mofetil, and prednisone. Subjects underwent lung function testing and cardiopulmonary exercise testing on a cycle ergometer. Results Peak exercise oxygen consumption (Vo2) was 22+/-8 ml/min/kg (66+/-20% predicted maximum). No subject demonstrated exercise desaturation or ventilatory limitation (peak minute ventilation 55+/-8% predicted maximum voluntary ventilation). Peak heart rate was 87+/-8% of predicted maximum. Early AT was evident (1.2+/-0.34 L/min, 48+/-11% predicted Vo2max). Conclusions Liver transplant recipients exhibit impaired peak exercise performance similar to that observed after other solid organ transplants, possibly as a result of chronic deconditioning or myopathy related to immunosuppressive medications.

Background . A new third generation porcine bioprosthesis was developed in an attempt to improve on hemodynamic performance and durability of current prostheses. Methods . One thousand, two hundred, sixty patients underwent aortic valve replacement and 366 patients underwent mitral valve replacement between February 1994 and September 2000. The cumulative follow-up was 3,696.3 patient-years for aortic valve replacement and 880.1 patient-years for mitral valve replacement. Follow-up was complete for 95.5% of aortic valve replacement patients and 97.5% of mitral valve replacement patients. Results . For aortic valve replacement, freedom from valve-related adverse events at 1 year was 96.5% ± 0.5% for antithromboembolic-related hemorrhage and 100% for structural valve deterioration. Freedom from valve-related adverse events at 5 years was 93.8% ± 2.6% for antithromboembolic-related hemorrhage and 99.3% ± 0.9% for structural valve deterioration. For mitral valve replacement, freedom from valve-related adverse events at 1 year was 96.0% ± 1.1% for antithromboembolic-related hemorrhage and 100% for structural valve deterioration. Freedom from valve-related adverse events at 4 years was 92.1% ± 3.7% for antithromboembolic-related hemorrhage and 100% for structural valve deterioration. Conclusions . These results support the claim that the Mosaic bioprosthetic valve is efficacious and safe, but continued follow-up is mandatory to determine mid- and long-term performance.

From 1975 to 1995, 4200 patients had bioprosthetic valve replacements (2240 aortic, 1607 mitral, 353 multiple) and 2038 had mechanical valve replacements (747 aortic, 928 mitral, 363 multiple). Freedom from major thromboembolism or both major thromboembolism and hemorrhage for aortic and mitral valve replacement at 15 years was significantly greater for bioprostheses than mechanical prostheses. Freedom from valve-related mortality and reoperation for both aortic and mitral valve replacements was the same for bioprostheses and mechanical prostheses. Advancing age increased overall mortality (all positions), valve-related mortality (aortic, mitral), major thromboembolism (aortic), thromboembolism and hemorrhage (aortic, mitral) but decreased reoperation (all positions). Coronary artery bypass grafting increased overall mortality (aortic, mitral) but not valve-related mortality, and it decreased reoperation rate (aortic, mitral). Overall mortality was not influenced by valve type in aortic or multiple valve replacement but it was decreased by bioprostheses in mitral valve replacement. Valve type did not influence valve-related mortality (all positions). Mechanical valves decreased reoperation only for aortic valve replacement but they increased major thromboembolism with and without hemorrhage for both aortic and mitral replacements. There is support for bioprostheses in aortic valve replacement and mechanical prostheses in mitral valve replacement but for neither in multiple valve replacements.

Although single-lung transplantation is an established therapy for respiratory failure secondary to emphysema, hyperinflation of the native lung with concomitant compression of the transplanted lung is emerging as a cause of morbidity. In non-transplant emphysematous patients with hyperinflated lungs, pneumectomy was found to improve pulmonary function and quality of life. We report our experience on 5 single-lung transplant recipients with emphysema who underwent lung volume reduction surgery (pneumectomy, bullectomy, or anatomic resection) following transplantation. There were no perioperative deaths. Three patients underwent lung volume reduction because of a progressive symptomatic decline in pulmonary function that was thought to be secondary to hyperinflation of the native lung. Two of these patients had a sustained improvement in lung function and functional status over several years. Two other patients underwent lung volume reduction for removal of suspicious pulmonary nodules in the native lung. Both patients had a subsequent improvement in forced expiratory volume in one second. In our experience, lung volume reduction surgery after single-lung transplantation in emphysematous patients was a safe means of providing long-term improvement in pulmonary function.

We present a case report of spontaneous hemothorax associated with neurofibromatosis. On review of the literature, a significant mortality rate of 36% is revealed in addition to a surgical mortality of 33%. Treatment options are reviewed and potential management strategies are discussed.

background The incidence of adenocarcinoma of the cardia is increasing. The surgical management remains controversial. The present study reviews our experience with surgically resected adenocarcinoma of the cardia. methods A retrospective review of 153 cases of surgically resected adenocarcinoma of the cardia was performed. Preoperative radiotherapy was used in 31 patients. The surgical approach, morbidity, mortality, impact of preoperative radiotherapy, and survival were determined. results The type of resection performed was a transhiatal esophagogastrectomy in 78%, a transthoracic esophagogastrectomy in 21%, and a transabdominal esophagogastrectomy in 1%. The in-hospital mortality rate was 4%. The frequency of complications was not associated with the use of preoperative radiotherapy or surgical approach. The 1-year (61%), 2-year (38%), 3-year (23%), and 5-year (16%) survival were not affected by the use of preoperative radiotherapy or surgical approach. Survival was significantly associated with stage and the presence of lymph node metastasis. conclusions Adenocarcinoma of the cardia is associated with a poor long-term prognosis. The long-term survival does not appear to be affected by the use of preoperative radiotherapy or by surgical approach.

The Carpentier-Edwards supra-annular porcine bioprosthesis (second generation prosthesis) was implanted in 2438 patients in 2482 operations between 1982 and 1992. The mean age of the population was 64 years with a range from 21 years to 89 years. There were 1334 aortic and 934 mitral valve replacements. The population was divided into five groups: 21 to 40 years (n = 132); 41 to 50 years (n = 189); 51 to 60 years (n = 454); 61 to 70 years (n = 849); and over 70 years (n = 858). There was no difference in sunival by valve position for age groups 21 to 40 years and 41 to 50 years. Sunival within the age groups 51 to 60 years, 61 to 70 years, and over 70 years was greater for patients with aortic compared with mitral and multiple valve replacements. The freedom from structural valve deterioration at 10 years for all age groups was highest for valves in the aortic position. Patients with valves in the mitral position had a higher freedom from structural valve deterioration at 10 years than those who had multiple valve replacement, although not all the differences were significant. There was a lower incidence of structural valve deterioration in the older age groups. We concluded that the use of the Carpentier-Edwards supra-annular porcine bioprosthesis for aortic valve replacement can be extended to patients over 60 years of age, while its use for mitral valve replacement can be extended to those above 70 years of age.

A group of 1195 patients who received biological valve prostheses (mean age 57.3 years, range 8 to 85 years) and a group of 1345 patients who received mechanical heart valves (mean age 56.1 years, range 13 to 91 years) were analyzed for complications by age group (less than or equal to 54 years, 55 to 65 years, and over 65 years). The freedom from thromboembolism and anticoagulant-related hemorrhage at 8 years after aortic valve replacement was significantly higher in patients who received a biological prosthesis in all age groups. The freedom from thromboembolism and anticoagulant-related hemorrhage at 8 years after mitral valve replacement was significantly higher in patients who received a biological prosthesis in the age groups less than or equal to 54 years and over 65 years. The freedom from all valve-related complications at 5 and 8 years after aortic or mitral valve replacement showed the same trend of greater freedom from complications in biological prostheses patients compared with mechanical prostheses in most age groups. However, freedom from valve-related reoperation, mortality, and residual morbidity for aortic and mitral valve replacement for all age groups was not significantly different. These results show that biological prostheses can be considered for patients aged 55 years and older. The prostheses by age group or position at 8 years were not differentiated by valve-related reoperation, mortality, and residual morbidity. t 8 years there is a demonstrated price to pay for a presumed increase in longevity for patients with mechanical valves in the aortic position, reflected by an increase in thromboembolism and anticoagulant-related hemorrhage in all age groups.

BACKGROUND: Transbronchial lung biopsy results are crucial for the management of lung transplant recipients. Little information is available regarding the reliability and reproducibility of the interpretation of transbronchial lung biopsies.OBJECTIVE: To examine the inter-reader variability between two lung pathologists with expertise in lung transplantation.METHODS: Fifty-nine transbronchial lung biopsy specimens were randomly selected. Active infection had been excluded in all cases. The original interpretations (as per the Lung Rejection Study Group) for acute rejection grade included 19 biopsies scored as A0 (none), 14 scored as A1 (minimal), 12 as A2 (mild), 11 as A3 (moderate) and three as A4 (severe). The pathologists worked independently without clinical information or knowledge of the original interpretation. The specimens were graded using the Lung Rejection Study Group criteria for acute rejection (grades A0 to A4), airway inflammation (grades B0 to B4) and bronchiolitis obliterans (C0 absent and C1 present). Between-reader agreement for each category was analyzed using a Kappa statistic.RESULTS: Because many transplant specialists initiate augmented immunosuppression with biopsy grades of A2 or higher, results for each reader were dichotomized as A0/A1 versus A2/A3/A4. Using this dichotomy, there was only moderate agreement (kappa 0.470, PCONCLUSIONS: Because the agreement between expert pathologists is only modest, optimum clinical decision-making requires that transbronchial lung biopsy results be used in an integrated clinical context.

The Carpentier-Edwards standard (CE-S) porcine bioprosthesis was implanted in 1214 operations (1975 to 1985) and the Carpentier-Edwards supraannular (CE-SAV) bioprosthesis was implanted in 2,489 operations (1982 to 1992 inclusive). The early mortality was 7.6% and 7.4% for the CE-S and CE-SAV groups, respectively; the late mortality was 5.3% per patient-year and 4.9% per patient-year, respectively. The cumulative follow-up was 9,968 patient-years for the CE-S group and 12,784 patient-years for the CE-SAV group. Concomitant procedures were performed in 26.8% of the patients who received a CE-S and in 40.9% of those who received a CE-SAV (p0.05). The mean age of the patients receiving a CE-S was 57.3 years (range, 8 to 85 years) and was 64.1 years (range, 6 to 89 years) in those receiving a CE-SAV. The CE-S group consisted of 578 atrial valve replacements (AVRs), 512 mitral valve replacements (MVRs), and 115 multiple valve replacements (MRs). The CE-SAV group consisted of 1,335 AVRs, 938 MVRs, and 200 MRs. There was a total of 165 cases of structural valve deterioration (SDV) in the CE-SAV group (AVR, 35; MVR, 98; and MR, 32). The effect of trimming the aortic wall was also considered: 20 of the 931 trimmed prostheses used for MVRs and MRs and none of the 207 reduced-trimmed prostheses exhibited SVD. The cumulative follow-up was 5,422 years for the patients with trimmed prostheses and 470 for those with reduced-trimmed prostheses.(ABSTRACT TRUNCATED AT 250 WORDS)

Prosthetic valve replacement remains the most viable alternative for the treatment of severely diseased heart valves. The cumulative experience of mechanical protheses and bioprostheses was evaluated for a 10-year performance comparison: Carpentier-Edwards standard porcine bioprosthesis (CE-S), 1,214 operations; Carpentier-Edwards supraannular porcine bioprosthesis (CE-SAV), 2,489; and mechanical prostheses, 1,364 operations (St. Jude Medical, Carbomedics, Duromedics, and Björk-Shiley Monostrut). The freedom from thromboembolism and hemorrhage at 10 years was 82% for CE-S, 78% for CE-SAV, and 65% for mechanical prostheses (p0.05). The relationship existed for major thromboembolism and hemorrhage, 91% (CE-S), 87% (CE-SAV), and 88% (mechanical) (p0.05), without clinical relevance. The freedom from structural valve deterioration and valve-related reoperation favored mechanical prostheses (p0.05) at 10 years (structural failure: 78% for CE-S, 81% for CE-SAV, and 99% for the mechanical group; reoperation: 74% for CE-S, 76% for CE-SAV, and 88% for mechanical prostheses). The freedom from fatal reoperation was not clinically different: 96% for CE-S, 99% for CE-SAV, and 99% for mechanical prostheses (p0.05) at 10 years. The freedom from valve-related mortality was not different (p = not significant) at 10 years: 87% for CE-S; 92% for CE-SAV; and 91% for mechanical. The freedom from permanent impairment or residual morbidity, primarily from thromboembolism, was 95% for CE-S, 92% for CE-SAV, and 95% for mechanical group (p0.05) but not clinically relevant.(ABSTRACT TRUNCATED AT 250 WORDS)

Background The frequency and causes of gastrointestinal complications following esophagectomy for malignancy are unknown. Patients and methods We reviewed 295 esophagectomies performed for malignancy between January 1980 and September 1994 in order to determine the frequency and causes of early and late gastrointestinal complications. Results Compared to transhiatal and left thoracoabdominal esophagectomies, esophagectomies carried out through a right posterolateral thoracotomy with cervical esophagogastric anastomosis had a higher incidence of delayed gastric emptying (11%), pneumonia (26%), and hospital death (9%). The same operation had a higher incidence of gastroesophageal reflux (20%) and dysphagia requiring esophageal dilatation (53%). We found no independent effect of gastric drainage procedures, feeding jejunostomy, preoperative radiotherapy, pathology, or age on these outcomes. Women had no operative mortality, but a higher incidence of gastroesophageal reflux and diarrhea following esophagectomy. Conclusions Surgical techniques aimed at improving gastric emptying following esophagectomy for cancer should improve operative morbidity and mortality.

Background Guided by the evidence that delaying coronary revascularization may lead to symptom worsening and poorer clinical outcomes, expansion in cardiac surgery capacity has been recommended in Canada. Provincial governments started providing one-time and recurring increases in budgets for additional open heart surgeries to reduce waiting times. We sought to determine whether the year of decision to proceed with non-emergency coronary bypass surgery had an effect on time to surgery. Methods Using records from a population-based registry, we studied times between decision to operate and the procedure itself. We estimated changes in the length of time that patients had to wait for non-emergency operation over 14 calendar periods that included several years when supplementary funding was available. We studied waiting times separately for patients who access surgery through a wait list and through direct admission. Results During two periods when supplementary funding was available, 1998–1999 and 2004–2005, the weekly rate of undergoing surgery from a wait list was, respectively, 50% and 90% higher than in 1996–1997, the period with the longest waiting times. We also observed a reduction in the difference between 90th and 50th percentiles of the waiting-time distributions. Forty percent of patients in the 1998, 1999, 2004 and 2005 cohorts (years when supplementary funding was provided) underwent surgery within 16 to 20 weeks following the median waiting time, while it took between 27 and 37 weeks for the cohorts registered in the years when supplementary funding was not available. Times between decision and surgery were shorter for direct admissions than for wait-listed patients. Among patients who were directly admitted to hospital, time between decision and surgery was longest in 1992–1993 and then has been steadily decreasing through the late nineties. The rate of surgery among these patients was the highest in 1998–1999, and has not changed afterwards, even for years when supplementary funding was provided. Conclusions Waiting times for non-emergency coronary bypass surgery shortened after supplementary funding was granted to increase volume of cardiac surgical care in a health system with publicly-funded universal coverage for the procedure. The effect of the supplementary funding was not uniform for patients that access the services through wait lists and through direct admission.

A 51-year-old woman with a peritoneovenous shunt for refractory ascites presented with three months of increasing fatigue, exertional dyspnea, night sweats and positive blood cultures. Imaging revealed multiple pulmonary emboli. Transthoracicnbsp; chocardiography demonstrated moderate tricuspid regurgitation and a large pedunculated right atrial mass attached to the interatrial septum. The echocardiographic appearance remained unchanged after one month of antibiotic therapy andnbsp; nticoagulation. Intraoperatively, the mass was easily excised and the grossly abnormal tricuspid valve replaced. Pathology revealed endocarditis with multiple bacterial colonies, and fibromyxoid changes consistent with postinflammatory valve disease.

Background The Mosaic porcine bioprosthesis (Medtronic, Inc, Minneapolis, Minn) was approved in 2000 by the US Food and Drug Administration. Clinical performance was evaluated in 6 centers. Methods From 1994 to 2000, 797 patients (mean age 69 years) had aortic valve replacement (AVR) and 232 (mean 67 years) had mitral valve replacement (MVR). Concomitant coronary artery bypass grafting was performed with aortic valve replacement (45.4%) and mitral valve replacement (43.5%). Mean follow-ups were 7.5 years for aortic position and 7.3 years for mitral position. Results Early mortalities were 2.8% for AVR and 3.0% for MVR. Late mortalities were 4.2%/patient-year for AVR and 5.1%/patient-year for MVR. Overall 12-year survivals were 55.8% ± 3.7% for AVR and 43.9% ± 7.4% for MVR. Twelve-year freedoms from valve-related mortality were 87.1% ± 3.1% for AVR and 82.5% ± 7.7% for MVR. Twelve-year freedoms from reoperation were 84.0% ± 3.3% for AVR and 82.5% ± 7.5% for MVR. Freedoms from structural valve deterioration (SVD) by explant reoperation at 12 years for AVR were 93.3% ± 2.6% for patients at least 60 years old and 75.9% ± 9.3% for patients younger than 60 years. Freedoms from SVD by explant reoperation at 10 years for MVR were 95.3% ± 7.8% for patients at least 70 years old and 84.0% ± 9.3% for patients younger than 70 years. Hemodynamic performance data at 1 year for AVR (sizes 21–27 mm) were mean systolic gradient range 13.7 ± 4.8 to 10.3 ± 3.2 mm Hg and effective orifice area range 1.5 ± 0.3 to 2.5 ± 0.4 cm 2 . For MVR (sizes 25–31 mm), data were mean diastolic gradient range 6.7 ± 1.7 to 3.7 ± 0.9 mm Hg and effective orifice area range 1.9 ± 0.3 to 2.4 ± 0.6 cm 2 . Conclusions Overall performance of Mosaic porcine bioprosthesis to 12 years is satisfactory. Freedoms from SVD by explant reoperation were most satisfactory for aortic position in patients at least 60 years old and mitral position in patients at least 70 years old. Overall actuarial freedom from SVD by explant reoperation is encouraging for patients with MVR.

Objectives Long-term thromboembolic and hemorrhagic outcomes after mechanical valve replacement have been well described; however, few studies have described these outcomes after valve replacement with the On-X mechanical prosthesis (On-X Life Technologies, Inc, Austin, Tex). Methods Between 2003 and 2008, 737 patients underwent either aortic valve replacement (n = 400), mitral valve replacement (n = 282), or double-valve replacement (n = 55). Longitudinal performance, freedom evaluation, and risk analysis were assessed with regard to major thromboembolism and hemorrhage. Risk modeling was performed with 16 variables inclusive of age, atrial fibrillation, concomitant coronary artery bypass grafting, New York Heart Association class, and ventricular dysfunction. Results Early mortality was 2.5% (n = 10) for aortic valve replacement and 3.2% (n = 9) for mitral valve replacement. Late mortality for aortic valve replacement was 4.8% per patient-year and 6.0% per patient-year for mitral valve replacement. Five-year freedom from major thromboembolism was 96.5% ± 1.2% for aortic valve replacement and 97.7% ± 0.9% for mitral valve replacement. Five-year freedom from hemorrhage was 93.6% ± 1.8% for aortic valve replacement and 95.7% ± 1.5% for mitral valve replacement. Concomitant coronary artery bypass grafting was predictive of major thromboembolism after aortic valve replacement (hazard ratio, 5.3; P = .02) and antithrombotic hemorrhage after mitral valve replacement (hazard ratio, 4.7; P = .03). No other independent predictors of major thromboembolism or hemorrhage were identified. One thrombosed mitral prosthesis was observed after deliberate discontinuation of anticoagulation. The major thromboembolic events occurred with variation of international normalized ratio levels inclusive of subtherapeutic levels. The majority of hemorrhagic events occurred with high international normalized ratio levels. Conclusions The On-X mechanical prosthesis provides favorable intermediate-term results with regard to major thromboembolism and hemorrhage.

Objective:The durability of mitral bioprostheses has long been known to be inferior to aortic bioprostheses. Mitral valvereconstruction/repair is currentlyrecommendedfor mostmitralvalveprocedures. Thechoiceof prostheses for non-reparable or failedmitralvalverepairshas not been specified or given appropriate attention within the literature. The objective of this study is to address the role of bioprostheses in the specific subset of non-reparable or failed repair patients by using the knowledge of the general durability of mitral porcine bioprostheses, inclusive of the Carpentier-Edwards mitral porcine bioprosthesis. Methods: The CE-SAV was implanted in 1135 patients (1175 operations) for mitral valve replacement (MVR) from 1982 to 2000. The mean age was 65.0 12.1 years (range 13—86 years). The mean follow-up was 6.4 4.5 years, 7555.9 patient-years and 98.3% complete.The evaluation consideredfreedom from structuralvalve deterioration (SVD) and freedom from composites of complications, as well as risk assessment. Results: For the 51—60 year age group, the actual and actuarial freedom from SVD was, at 18 years, 56.0 4.1% and 14.7 5.8%; for the 61—70 year age group was, at 18 years, 69.6 2.6% and 26.5 5.9%, respectively. For the >70 group, at 15 years was 92.2 2.0% and 69.0 9.7%, respectively. There were a total of 256 SVD events with 31 fatalities and 226 reoperations with 10 fatalities (4.42%). The predictors of SVD were age (hazard ratio [HR] 0.98, p = 0.0002), concomitant CAB (HR 0.66, p = 0.020) and valve size (HR 1.08, p = 0.034). The overall actual freedom, at 15—18 years, for >70 age group was, for valve-related reoperation, 94.3 1.5%; and for valverelated mortality was 87.8 2.3%. Conclusions: The CE-SAV mitral porcine bioprosthesis cannot be recommended as representative of prosthesis-type of choice for non-reparable or failed repair of native mitral valves for ages 70 years. The CE-SAV mitral porcine bioprosthesis is satisfactory for implantation >70 years of age. The clinical performance of the CE-SAV is similar to other mitral bioprostheses. # 2008 European Association for Cardio-Thoracic Surgery. Published by Elsevier B.V. All rights reserved.

The correlation between plaque morphology as well as composition and plaque vulnerability has been the motivation for many recent studies. In a generic point of view, instability of atherosclerotic plaques is known to be

St. Jude Medical (SJM) bileaflet mechanical valves were approved by the Food and Drug Administration in 1977. The SJM valve design consists of two semicircular leaflets which pivot on hinges. Compared to other mechanical heart

The Mosaic valve is a third-generation stented porcine bioprosthesis built upon the historical durability of the Hancock II valve in an attempt to improve hemodynamic performance and durability.This multicenter trial was prospective and non-randomized in design. Between February 1994 and October 1999, six centers following a common study protocol enrolled 797 patients (mean age 70 years: range: 21-88 years) who underwent aortic valve replacement (AVR), and 232 patients (mean age 68 years; range: 17-84 years) who underwent mitral valve replacement (MVR). The cumulative follow up was 3,442 patient-years (pt-yr) for AVR (mean 4.3 years; maximum 8 years), and 870 pt-yr for MVR (mean 3.7 years; maximum 7 years). Follow up was complete for 95% of AVR patients, and for 97% of MVR patients.The mean gradient and calculated effective orifice area average across all valve sizes remained stable at one, four and six years. Freedom from valve-related adverse events (mean +/- SE) at one, four and seven years after AVR were, respectively: Antithromboembolic-related hemorrhage (ARH) 97.0 +/- 0.6, 95.6 +/- 0.9, and 94.6 +/- 5.1%; primary hemolysis 100, 100, and 100%; and structural valve deterioration (SVD) 100, 100 and 100%. Freedom at one, four and seven years after MVR were: ARH 96.9 +/- 1.2, 95.6 +/- 2.0, and 95.6 +/- 7.6%; primary hemolysis 100, 100, and 100%; and SVD 100, 100, and 100%.These mid-term results demonstrate the clinical safety and excellent performance of the Mosaic valve. Continued follow up will determine if this new-design, third-generation bioprosthesis will provide increased durability.

Objective: The predominant complication of bioprostheses is structural valve deterioration and the consequences of re-operation. Prosthesis choice for aortic valve replacement surgery (bioprostheses and mechanical prostheses), is influenced by valve-related complications (mortality and morbidity) of the prosthesis type chosen. The purpose of the study is to determine the mortality and risk assessment of that mortality for aortic bioprosthetic failure. Methods: From 1975 to 1999, 3356 patients received a heterograft bioprosthesis in 3530 operations. The procedures were performed with concomitant coronary artery bypass (CAB) in 1388 procedures and without in 2142 procedures. Three hundred twenty-two re-operations for structural valve deterioration were performed in 312 patients with 22 fatalities (6.8%). Of the 322 re-replacements, 36 had CAB and 286 had isolated replacement; the mortality was 8.3% (3) and 6.6% (19), respectively. Eleven predictive factors inclusive of age, concomitant CAB, urgency status, New York Heart Association (NYHA) at Re-op and year of Reop (year periods) were considered. Results: The mortality for 1979– 1986 was 6.1% (2/33); 1987– 1992, 7.7% (8/104); and 1993– 2000, 6.5% (12/185) (pNS). The mortality by urgency status for elective/urgent was 6.4% (19/299); and emergent, 13.0% (3/23) (pNS). The mortality for NYHA I/II was 2.0% (1/50), III 4.2% (8/191) and IV 16.0% (13/81) (P ¼ 0:00063), for gender was male 4.6% and female 13.3% (P ¼ 0:011), for age at implant ‘No’ (no re-operation) 51.6 ^ 12.2 years and ‘Yes’ (yes re-operation) 59.9 ^ 7.3 years (P ¼ 0:00004), for age at explant ‘No’ 62.6 ^ 12.7 years and ‘Yes’ 70.6 ^ 6.5 years (P ¼ 0:00001), and for age at explant , 60 years 0.0% (0/110), 60 – 70 years 8.5% (10/117) and . 70 years 12.6% (12/95) (P ¼ 0:0011). The predictive risk factor assessment by multivariate regression analysis revealed only NYHA III Odds Ratio 1.7 and IV 7.8 P ¼ 0:0082. For the period 1993– 2000 of re-operations only gender was significant; age at implant, age at explant, CAB pre-Re-op, CAB concomitant with Re-op, urgency at Re-op, ejection fraction, valve lesion and NYHA at Re-op were not significant. Conclusions: Bioprosthetic aortic re-operative mortality can be lowered by re-operation in low rather than medium to severe NYHA functional class. The routine evaluation of patients can achieve earlier low risk re-operative surgery.