In Vitro Matured Human Pluripotent Stem Cell-Derived Cardiomyocytes Form Grafts With Enhanced Structure and Function in Injured Hearts.

BACKGROUND: Human pluripotent stem cell (hPSC)-derived cardiomyocytes (hPSC-CMs) have tremendous promise for application in cardiac regeneration, but their translational potential is limited by an immature phenotype. We hypothesized that large-scale manufacturing of mature hPSC-CMs could be achieved through culture on polydimethylsiloxane (PDMS)-lined roller bottles and that the transplantation of these cells would mediate better structural and functional outcomes than with conventional immature hPSC-CM populations. METHODS: We comprehensively phenotyped hPSC-CMs after in vitro maturation for 20 and 40 days on either PDMS or standard tissue culture plastic substrates. All hPSC-CMs were generated from a transgenic hPSC line that stably expressed a voltage-sensitive fluorescent reporter to facilitate in vitro and in vivo electrophysiological studies, and cardiomyocyte populations were also analyzed in vitro by immunocytochemistry, ultrastructure and fluorescent calcium imaging, and bulk and single-cell transcriptomics. We next compared outcomes after the transplantation of these populations into a guinea pig model of myocardial infarction using end points including histology, optical mapping of graft- and host-derived action potentials, echocardiography, and telemetric electrocardiographic monitoring. RESULTS: We demonstrated the economic generation of >1×108 mature hPSC-CMs per PDMS-lined roller bottle. Compared with their counterparts generated on tissue culture plastic substrates, PDMS-matured hPSC-CMs exhibited increased cardiac gene expression and more mature structural and functional properties in vitro. More important, intracardiac grafts formed with PDMS-matured myocytes showed greatly enhanced structure and alignment, better host-graft electromechanical integration, less proarrhythmic behavior, and greater beneficial effects on contractile function. CONCLUSIONS: We describe practical methods for the scaled generation of mature hPSC-CMs and provide the first evidence that the transplantation of more mature cardiomyocytes yields better outcomes in vivo.

Valve-sparing aortic root replacement: a primer for cardiologists.

PURPOSE OF REVIEW: The purpose of this article is to review the contemporary evidence supporting valve-sparing aortic root replacement as the best option for patients with aortic root aneurysms and preservable aortic valves as well as to review the technical variations and modern adjuncts of these operations that impact both short and long-term durability. RECENT FINDINGS: In patients with an aortic root aneurysm, with or without aortic valve regurgitation, valve-sparing aortic root replacement provide excellent clinical outcomes and stable valve function over several decades. Successful execution of this operation depends on careful patient selection and a thorough understanding of the anatomical and physiological relationships between the various components of the aortic root. Echocardiography remains the mainstay of imaging to determine the feasibility of valve-sparing root replacement. SUMMARY: Valve-sparing aortic root replacement is an excellent alternative to composite valve graft replacement in nonelderly patients with aortic root aneurysms. Dedicated aortic root surgeons perform several technical variations of valve-sparing procedures aimed at matching the specific aortic root disorder with the optimal operation.

Supporting the Ross procedure: preserving root physiology while mitigating autograft dilatation.

PURPOSE OF REVIEW: The purpose of this article is to describe the optimized approach to nonrepairable aortic valve disease in young adults with a Ross procedure, while preserving the dynamic physiology of the aortic root. RECENT FINDINGS: As the techniques for supporting pulmonary autografts continue to be refined, and the applicability of the Ross procedure continues to expand, an assessment of the various techniques based on aortic root physiology is warranted. Semi-resorbable scaffolds show promise in ovine models for improving the Ross procedure. Recent long-term outcomes for the Dacron inclusion technique in comparison to more physiologic methods of support emphasize the importance of balancing the prevention of early dilatation with the preservation of root haemodynamics. As this review will synthesize, the dynamic physiology of the root may be preserved even in patients at a higher risk of autograft dilatation. SUMMARY: The favourable long-term outcomes of the Ross procedure can be partly attributed to the ability of the autograft to restore dynamism to the neoaortic root. Patient-specific modifications that respect root physiology can tailor the Ross procedure to address each patient's risk factors for early dilatation and late failure. As such, the Ross procedure should be recognized as an increasingly favourable solution for a wide spectrum of nonpreservable aortic valve disease in young adults.

Revascularization strategies for left main coronary artery disease: current perspectives.

PURPOSE OF REVIEW: Left main coronary artery disease (LMCAD) represents a high-risk subset of coronary artery disease with significant morbidity and mortality if not treated in a timely manner. In this review, we survey the contemporary evidence on the management of LMCAD, highlight advances, and provide in-depth review of data comparing surgical and percutaneous approaches. RECENT FINDINGS: LMCAD represents a heterogeneous condition and management should be guided by key clinical and anatomic factors. In recent years, there has been a wealth of published prospective data including results of the EXCEL and NOBLE trials. Coronary artery bypass graft (CABG), remains the gold standard for optimal long-term outcomes and the greatest benefit seen in patients with higher anatomic complexity and longer life expectancy. Percutaneous coronary intervention (PCI) offers a less-invasive approach with rapid recovery. PCI is optimal in situations when surgery cannot be offered in a timely manner due to hemodynamic instability, for high-risk surgical patients, or those with limited life expectancy, if LMCAD is anatomically simple. As a result of continued technological and procedural improvements in both PCI and CABG, cardiovascular specialists possess a growing armamentarium of approaches to treat LMCAD. Thus, center specialization and use of a heart team approach are increasingly vital, though barriers remain. SUMMARY: Emerging evidence continues to support CABG as the gold standard for achieving optimal long-term outcomes in patients with LMCAD. PCI offers a more expeditious approach with rapid recovery and is a safe and effective alternative in appropriately selected candidates.

Navigating the Postgraduate Research Fellowship: A Roadmap for Surgical Residents.

BACKGROUND: To preserve the future of surgical innovation, opportunities for surgical residents to receive structured research training are paramount. The objective of this article is to help surgical residents navigate a research fellowship by overviewing key topics such as choosing an area of focus and supervisor, applying for external funding, transitioning away from clinical duties, managing intellectual property, integrating family planning, and incorporating research experience into independent career development. MATERIALS AND METHODS: Using the framework of the University of Toronto's graduate degree-awarding Surgeon-Scientist Training Program, the authors outline key considerations, decisions, and pearls for surgical residents considering or currently enrolled in a full-time research fellowship training program. RESULTS: Full-time research fellowships offer a unique opportunity for residents interested in an academic career. Such full-time research fellowships away from clinical duties allow surgical trainees to focus on developing key research competencies, including how to generate hypotheses, apply research methodology, gain experience presenting and publishing manuscripts, and ultimately apply these skills as independent investigators to improve patient and population health. Research fellowships may also be an opportunity to develop intellectual property or facilitate family planning. Practical tips are provided for the transition back into clinical training and how to effectively market one's research skills for career advancement. CONCLUSIONS: The authors outline key considerations, decisions, and pearls for surgical residents considering or currently enrolled in a full-time research fellowship training program. By adhering to the principles highlighted in this article, residents will be able to successfully navigate a full-time research fellowship to optimize their intellectual development, maximize their academic productivity, and facilitate their transition into an independent investigator.

Early failure of aortic bioprostheses: what are the mechanisms?

PURPOSE OF REVIEW: The purpose of this study is to review the contemporary evidence surrounding aortic bioprosthetic valve deterioration, with a focus on early failure of surgically implanted valves. RECENT FINDINGS: Structural valve deterioration (SVD) remains the most frequent cause of premature bioprosthetic aortic valve failure. However, recent evidence suggests that SVD represents a spectrum, and that clinically silent hemodynamic valve deterioration frequently precedes and predisposes to overt SVD. Hemodynamic valve deterioration is defined as an increase in mean transprosthetic gradient and/or worsening transprosthetic regurgitation on echocardiography. Novel evidence suggests that a dysmetabolic profile may predispose to this phenomenon. Furthermore, subclinical leaflet thrombosis is increasingly recognized as a potential cause of hemodynamic deterioration of bioprosthetic valves. Collectively, these findings highlight the importance of systematic and regular imaging surveillance following bioprosthetic aortic valve replacement. SUMMARY: Early failure of bioprosthetic aortic valves is a complex and multifactorial phenomenon. Further studies are needed to determine the optimal timing and imaging modality for surveillance following bioprosthetic aortic valve replacement, and to establish strategies to prevent and treat aortic bioprosthetic failure.

Anomalous origins of the coronary arteries: current knowledge and future perspectives.

PURPOSE OF REVIEW: The purpose of this review is to survey the contemporary literature surrounding congenital anomalies of origin of the coronary arteries and to identify remaining gaps in knowledge. RECENT FINDINGS: In recent years, lineage tracing analyses and mechanistic studies in model organisms have enhanced our understanding of the normal embryologic development of the coronary arteries, and how disruption of this intricate process can lead to congenital coronary anomalies. The true incidence of these anomalies remains unknown. Although a majority of cases are believed to be clinically silent, clinical presentation varies widely, from asymptomatic to sudden cardiac death. Cardiac computed tomography angiography and/or magnetic resonance angiography are the mainstay diagnostic modalities. Management of anomalous coronary arteries depends on the morphology and clinical presentation. Surgery is the gold-standard treatment for anomalous left coronary artery arising from the pulmonary artery and anomalous aortic origin of a coronary artery with intramural or interarterial course. SUMMARY: Several large multicenter initiatives are currently underway and should help address some of the numerous knowledge gaps surrounding the evaluation and management of anomalous coronary arteries.

Systematic review and meta-analysis in cardiac surgery: a primer.

PURPOSE OF REVIEW: The purpose of this article is to review the strengths and weaknesses of systematic reviews and meta-analyses to inform our current understanding of cardiac surgery. RECENT FINDINGS: A systematic review and meta-analysis of a focused topic can provide a quantitative estimate for the effect of a treatment intervention or exposure. In cardiac surgery, observational studies and small, single-center prospective trials provide most of the clinical outcomes that form the evidence base for patient management and guideline recommendations. As such, meta-analyses can be particularly valuable in synthesizing the literature for a particular focused surgical question. Since the year 2000, there are over 800 meta-analysis-related publications in our field. There are some limitations to this technique, including clinical, methodological and statistical heterogeneity, among other challenges. Despite these caveats, results of meta-analyses have been useful in forming treatment recommendations or in providing guidance in the design of future clinical trials. SUMMARY: There is a growing number of meta-analyses in the field of cardiac surgery. Knowledge translation via meta-analyses will continue to guide and inform cardiac surgical practice and our practice guidelines.

Clinical trials in valvular surgery: a 2018 update.

PURPOSE OF REVIEW: There is a growing emphasis on the conduct of large-scale, multicenter randomized controlled trials (RCTs) to guide decision-making in cardiac surgery. Here we review recent landmark RCTs in cardiac valvular surgery. RECENT FINDINGS: RCTs are the gold-standard level of data in medicine. However, there are unique challenges of conducting large-scale surgical trials including funding, blinding, generalizability, nonstandardization of the surgical technique, crossover, among others. Thus, the vast majority of clinical outcomes data in cardiac surgery are mainly from observational studies and most prospective data are small, single-center trials. The Cardiothoracic Surgery Network is the largest platform focused on the conduct of high-quality, multicenter cardiac surgical trials, which has already produced several seminal guideline-changing and practice-changing contributions to the surgical approach to functional mitral regurgitation, aortic stenosis, atrial fibrillation, and neuroprotective surgical adjuncts. SUMMARY: There continues to be great interest in the conduct of high-quality, RCTs to help guide surgical management of patients with valvular heart disease.

Morbidity After Cardiac Surgery in Patients With Adult Congenital Heart Disease in Comparison With Acquired Disease.

BACKGROUND: Due to the advancements in congenital cardiac surgery and interventional cardiology in the last 5 decades, more than 85% of congenital heart patients now survive to adulthood. METHODS: This retrospective study included 135 Adult Congenital Heart Disease (ACHD) patients, who had cardiac surgery at Southampton General Hospital over 3 consecutive years. We also included 42 patients with a structurally normal heart who had cardiac surgery for acquired cardiac conditions as a control group. Preoperative, intraoperative and postoperative data were analysed in both groups to identify risk factors for morbidity and mortality. RESULTS: In the ACHD group, in hospital mortality was 0.7%. In the control group no deaths were observed. Fifty-eight per cent of the ACHD patients had significantly higher perioperative morbidity with arrhythmias (26%), bleeding (3%), prolonged ventilation (11.3%) and renal replacement therapy 1.5%. In the non ACHD control group 32% (p=0.003) developed perioperative complications with arrhythmias (9.8%), bleeding (2.5%), prolonged ventilation (4.3%) and renal replacement therapy (2.5%). In ACHD patients total in-hospital stay was longer in patients with longer cardiopulmonary bypass (CPB) time (p=0.005), aortic cross clamp time (p=0.013) and higher preoperative alkaline phosphatase level (p=0.005). Early postoperative complications were higher in ACHD patients with longer cardiopulmonary bypass time (p=0.04) and presence of pulmonary artery hypertension (p=0.012). CONCLUSIONS: Even though the preoperative and operative characteristics are similar to both groups, the morbidity is more in ACHD group. Longer CBP time, aortic cross clamp time and presence of pulmonary hypertension are risk factors for higher morbidity in this group.

Long-Term Outcomes of the Ross Procedure Versus Mechanical Aortic Valve Replacement: Propensity-Matched Cohort Study.

BACKGROUND: The ideal aortic valve substitute in young and middle-aged adults remains unknown. We sought to compare the long-term outcomes of patients undergoing the Ross procedure and those receiving a mechanical aortic valve replacement (AVR). METHODS: From 1990 to 2014, 258 patients underwent a Ross procedure and 1444 had a mechanical AVR at a single institution. Patients were matched into 208 pairs through the use of a propensity score. Mean age was 37.2±10.2 years, and 63% were male. Mean follow-up was 14.2±6.5 years. RESULTS: Overall survival was equivalent (Ross versus AVR: hazard ratio, 0.91, 95% confidence interval, 0.38-2.16; P=0.83), although freedom from cardiac- and valve-related mortality was improved in the Ross group (Ross versus AVR: hazard ratio, 0.22; 95% confidence interval, 0.034-0.86; P=0.03). Freedom from reintervention was equivalent after both procedures (Ross versus AVR: hazard ratio, 1.86; 95% confidence interval, 0.76-4.94; P=0.18). Long-term freedom from stroke or major bleeding was superior after the Ross procedure (Ross versus AVR: hazard ratio, 0.09; 95% confidence interval, 0.02-0.31; P<0.001). CONCLUSIONS: Long-term survival and freedom from reintervention were comparable between the Ross procedure and mechanical AVR. However, the Ross procedure was associated with improved freedom from cardiac- and valve-related mortality and a significant reduction in the incidence of stroke and major bleeding. In specialized centers, the Ross procedure represents an excellent option and should be considered for young and middle-aged adults undergoing AVR.

The Ross procedure in adults: which patients, which disease?

PURPOSE OF REVIEW: The purpose of this article is to review the contemporary evidence surrounding the use of the Ross procedure in young and middle-aged adults and to identify the subset patients who are most likely to derive a benefit from this operation. RECENT FINDINGS: In appropriately selected young and middle-aged adults undergoing aortic valve replacement (AVR), the Ross procedure is currently the only operation that can restore long-term survival that is equivalent to that of the age-matched healthy general population. The ideal patient for the Ross procedure is a young, otherwise healthy adult with aortic stenosis and a small or normal size aortic annulus. In addition, this operation is particularly valuable in women contemplating pregnancy and patients with high level of physical activity, as well as those who wish to avoid the burden of lifelong anticoagulation. When carried out in expert centers with adequate surgical volumes, the Ross procedure is associated with superior long-term outcomes compared with prosthetic AVR, with minimal cost in terms of early morbidity and mortality. SUMMARY: Despite the expanding body of evidence demonstrating its long-term superiority over conventional prosthetic AVR in appropriately selected patients, the Ross operation remains largely underused. This situation mandates careful reexamination of current practice guidelines.

Sutureless aortic valves: who is the right patient?

PURPOSE OF REVIEW: Sutureless aortic valve replacement (AVR) has emerged as an alternative to traditional AVR for patients with aortic stenosis who present a higher surgical risk, such as the elderly, or those with small or highly calcified aortic roots. With transcatheter aortic valve implantation - the other major AVR alternative - being used in increasingly lower-risk patients, the place of sutureless valves in the AVR landscape needs to be defined. In this review, we discuss recent data and expert opinion as it pertains to the subject of sutureless AVR. RECENT FINDINGS: Several recent studies have evaluated the performance of sutureless valves in a variety of clinical contexts, including minimally invasive operations and high-risk surgical procedures. The optimal surgical technique for sutureless AVR has been refined through the publication of several reports addressing technical considerations. Reduction in operative times represents the main advantage of sutureless valves over conventional surgical prostheses, and the possibility of complete annular decalcification - and hence a reduced incidence of paravalvular leak - is the primary advantage over TAVI. SUMMARY: Sutureless valves have emerged as an attractive option for high-risk patients or for complex surgeries where a minimization of bypass time is critical. However, there is limited data regarding long-term outcomes, durability or reoperation.

Subclinical bioprosthetic aortic valve thrombosis: clinical and translational implications.

PURPOSE OF REVIEW: A recently published study has alerted the cardiovascular community to the existence of a significant and previously unrecognized risk of subclinical valve thrombosis following implantation of surgical and catheter-based bioprosthetic valves. The purpose of this article is to review our current understanding of this new clinical entity and to identify unanswered questions and areas for future research. RECENT FINDINGS: Subclinical bioprosthetic valve thrombosis (BPVT) is a more common phenomenon than previously appreciated. It appears that the incidence of BPVT is higher following transcatheter aortic valve replacement compared with surgical aortic valve replacement. Four-dimensional computed tomography (CT) is the most sensitive imaging modality for detection of leaflet immobility and subclinical BPVT. Certain echocardiographic findings, such as increasing transaortic gradients, increased cusp thickness and abnormal cusp mobility, predict the presence of BPVT on four-dimensional CT. There is a growing body of evidence linking subclinical BPVT with premature valvular hemodynamic deterioration and structural valve degeneration. Furthermore, subclinical leaflet thrombosis may constitute a nidus for unrecognized subacute cerebral or other thromboembolic events. Oral anticoagulation seems effective in both the prevention and treatment of BPVT. SUMMARY: Subclinical valve thrombosis is an important and underappreciated cause of early bioprosthetic valve failure. Although several recent studies have improved our understanding of this newly recognized clinical entity, a number of questions remain unanswered. Further studies are warranted to elucidate the true incidence of subclinical BPVT, its clinical consequences, as well as the optimal antithrombotic regimen following bioprosthetic valve implantation. The subgroups of patients at highest risk of BPVT will need to be identified for risk stratification purposes. Several ongoing clinical trials will shed some light on these important issues.

Year in review: complex valve reconstruction.

PURPOSE OF REVIEW: In recent years, great emphasis has been placed on reconstructive techniques for the surgical management of heart valve disease. In this review, we discuss recent data and current practice as it pertains to the subject of reconstructive valve surgery. RECENT FINDINGS: New techniques and an improved understanding of the mechanisms of aortic insufficiency have led to marked improvement in the early and late outcomes of aortic valve repair. While mitral valve repair is the established approach for the management of degenerative mitral valve disease, surgical technique continues to be refined, with valve reconstruction principles applied to increasingly challenging anatomy. Moreover, the introduction of novel biomaterials has allowed extension of the indication for valve reconstruction to circumstances of extensive tissue defect, including infective endocarditis. SUMMARY: Valve reconstruction is increasingly being recognized as an alternative to valve replacement. It alleviates the risks of prosthesis-related complications and is especially appealing in young and middle-aged adults. While early and midterm outcomes appear promising, further studies are warranted to assess the clinical benefit and long-term durability of complex valve reconstruction procedures.

Repair of Anterior Mitral Leaflet Prolapse: Comparison of Mid-Term Outcomes with Chordal Transposition and Chordal Replacement Techniques.

BACKGROUND: The repair of anterior mitral leaflet prolapse is known to be challenging. Hence, the study aim was to compare the mid-term results of anterior leaflet prolapse (ALP) using chordal transposition with results obtained using chordal replacement with expanded polytetrafluoroethylene (ePTFE) sutures. METHODS: Between 1999 and 2012, a total of 96 consecutive patients (mean age 62 years) with ALP underwent mitral valve repair at the authors' institution. Surgery involved either chordal transposition from the posterior to the anterior leaflet (n = 67), or chordal replacement using ePTFE sutures (n = 29). Clinical, operative and follow up data were recorded prospectively for each patient. The follow up was 100% complete (mean 3.4 years; range 0 to 12.9 years). RESULTS: Mitral valve repair was accomplished in all patients, with no operative mortality. The durations of cardiopulmonary bypass and aortic cross-clamp were significantly longer in the chordal replacement group. Actuarial overall survival at one, five and 10 years was 95 ± 3%, 87 ± 5% and 82 ± 7% versus 89 ± 6%, 89 ± 6% and 89 ± 6% in the chordal transposition and chordal replacement groups, respectively (p = 0.84). Freedom from reoperation in the two groups at five years was 95 ± 3% and 91 ± 7%, respectively (p = 0.24). The recurrence of moderate or severe mitral regurgitation (MR) (grade ≤2+) and of severe (grade ≤3+) MR was significantly higher in patients who underwent chordal replacement compared to chordal transposition (p = 0.04 and p = 0.01, respectively). CONCLUSIONS: Provided that chordal quality is preserved, chordal transposition is easier and quicker to achieve for ALP repair, and is also durable in the mid term. Chordal replacement offers a satisfying durability even if the recurrence of severe MR appears to be higher. Preferably, both surgical techniques should be mastered to allow valve repair when anatomic conditions prevent chordal transposition.

Moderate mitral regurgitation at the time of coronary bypass surgery: repair or leave it?

PURPOSE OF REVIEW: Moderate ischemic mitral regurgitation (IMR) is a common finding in patients undergoing coronary artery bypass grafting (CABG). In this review, we summarize the current evidence on the optimal management of this condition. RECENT FINDINGS: In recent years, several randomized clinical trials have assessed the impact of concomitant restrictive mitral annuloplasty at the time of CABG on reverse left ventricular remodeling, IMR reduction and clinical outcomes. SUMMARY: Surgical revascularization alone is a conservative strategy that reduces IMR in a significant proportion of patients. Concomitant restrictive annuloplasty provides better relief of mitral regurgitation in the immediate postoperative period, at the cost of increased perioperative morbidity. The only major randomized trial on the issue of moderate IMR published to date showed no difference in reverse left ventricular remodeling at 1 year between these two approaches. There are insufficient data in the literature to support the routine addition of mitral valve repair to CABG in patients with moderate IMR.

Early and mid-term outcomes of aortic annular enlargement: a systematic review and meta-analysis.

Background: There is mounting evidence at experienced centers that aortic annular enlargement (AAE) procedures are safe adjuncts to surgical aortic valve replacement (SAVR) that do not increase perioperative morbidity and mortality. This systematic review and meta-analysis aims to assess the impact of AAE procedures on mid-term outcomes after SAVR. Methods: OVID MEDLINE, OVID Embase, and Cochrane Library were searched comprehensively. Comparative studies examining adult patients undergoing SAVR with and without AAE were eligible for inclusion. Studies involving aortic root replacement, Ross procedures, and Ozaki procedures were excluded. The risk of bias was assessed according to Risk Of Bias In Non-randomized Studies of Interventions (ROBINS-I), and the quality of evidence was evaluated according to Grading of Recommendations Assessment, Development and Evaluation (GRADE). Random effects meta-analysis facilitated the quantitative synthesis. Results: A total of 2,765 records were retrieved. After full-text review, 15 eligible studies were identified for data extraction and synthesis. The dataset included a total of 216,654 patients (AAE: 7,967; no AAE: 208,687). Only mid-term outcomes were available. In unmatched and unadjusted studies, perioperative mortality was noted to be higher in the AAE group. However, this difference was not observed in studies with matching or adjusted outcomes. In both the unmatched and unadjusted studies, and the matched and adjusted studies, there were no statistically significant differences identified regarding perioperative stroke, myocardial infarction, or permanent pacemaker implantation. Similarly, there were no statistically significant differences identified in mid-term mortality [hazard ratio (HR), 1.03; 95% confidence interval (CI): 0.95 to 1.11; P=0.49; I2=20% (matched/adjusted studies)], aortic valve reintervention [HR, 0.98; 95% CI: 0.75 to 1.27; P=0.86; I2=0% (matched/adjusted studies)], or heart failure [HR, 1.06; 95% CI: 0.86 to 1.30; P=0.58; I2=25% (matched/adjusted studies)]. Conclusions: SAVR with AAE does not appear to be associated with increased perioperative morbidity or mortality. There is no conclusive indication that AAE enhances mid-term survival, freedom from reoperation, or freedom from heart failure after SAVR.

Improved Outcomes Following the Ross Procedure Compared With Bioprosthetic Aortic Valve Replacement.

BACKGROUND: The ideal aortic valve substitute for young and middle-aged adults remains elusive. OBJECTIVES: This study sought to compare the long-term outcomes of patients undergoing the Ross procedure and those receiving bioprosthetic aortic valve replacements (AVRs). METHODS: Consecutive patients aged 16-60 years who underwent a Ross procedure or surgical bioprosthetic AVR at the Toronto General Hospital between 1990 and 2014 were identified. Propensity score matching was used to account for differences in baseline characteristics. The primary outcome was all-cause mortality. Secondary outcomes included valve reintervention, valve deterioration, endocarditis, thromboembolic events, and permanent pacemaker implantation. RESULTS: Propensity score matching yielded 108 pairs of patients. The median age was 41 years (IQR: 34-47 years). Baseline characteristics were similar between the matched groups. There was no operative mortality in either group. Mean follow-up was 14.5 ± 7.2 years. All-cause mortality was lower following the Ross procedure (HR: 0.35; 95% CI: 0.14-0.90; P = 0.028). Using death as a competing risk, the Ross procedure was associated with lower rates of reintervention (HR: 0.21; 95% CI: 0.10-0.41; P < 0.001), valve deterioration (HR: 0.25; 95% CI: 0.14-0.45; P < 0.001), thromboembolic events (HR: 0.15; 95% CI: 0.05-0.50; P = 0.002), and permanent pacemaker implantation (HR: 0.22; 95% CI: 0.07-0.64; P = 0.006). CONCLUSIONS: In this propensity-matched study, the Ross procedure was associated with better long-term survival and freedom from adverse valve-related events compared with bioprosthetic AVR. In specialized centers with sufficient expertise, the Ross procedure should be considered the primary option for young and middle-aged adults undergoing AVR.

Opening the "Black Box" for Canadian Cardiac Surgery Residency Applicants∗.

Background: This study reports on the main criteria used by Canadian cardiac surgery residency program committees (RPCs) to select applicants and the perceptions of Canadian medical students interested in cardiac surgery. Methods: A 50-question online survey was sent to all 12 Canadian cardiac surgery RPCs. A similar 52-question online survey targeted at Canadian medical students interested in applying to cardiac surgery residency programs was distributed. Data from both surveys were analyzed using descriptive statistics. Results: A total of 62% of all cardiac surgery RPC members (66 of 106) participated, including committee members from all 12 programs (range: 1-12 members per program; 9%-100% response rate per program) and 67% of program directors (8 of 12). Forty-one Canadian medical students (22 pre-clerks [54%], 2 MD/PhD students [5%], and 17 clinical clerks [41%]) participated. Committee members considered the following criteria to be most important when selecting candidates: on-service clinical performance, the interview, quality of reference letters from cardiac surgeons, and completing a rotation at the target program's institution. In contrast, the following criteria relating to the candidate were considered to be less important: wanting to practice in the city or province of training, having a connection to the program location, and personally knowing committee members. Medical students' perceptions were concordant regarding what factors are the most important but they overestimated the influence of non-clinical factors and research productivity in increasing their competitiveness. Conclusion: Canadian cardiac surgery residency programs seek applicants who demonstrate clinical excellence, as assessed by surgical rotations and reference letters from colleagues, and strong interview performance.

Contexte: Cette étude fait état des principaux critères utilisés par les comités des programmes de résidence (CPR) canadiens en chirurgie cardiaque pour sélectionner les candidats, ainsi que des perceptions des étudiants en médecine canadiens qui s'intéressent à la chirurgie cardiaque. Méthodologie: Un sondage en ligne comptant 50 questions a été envoyé aux 12 CPR canadiens en chirurgie cardiaque. Un sondage en ligne semblable (comptant 52 questions) a été distribué aux étudiants en médecine qui souhaitaient soumettre leur candidature à un programme de résidence en chirurgie cardiaque au Canada. Les données des deux sondages ont été analysées à l'aide de statistiques descriptives. Résultats: Au total, 62 % des membres de CPR en chirurgie cardiaque (66 sur 106) ont répondu au sondage, y compris des membres des comités des 12 programmes (plage : 1 à 12 membres par programme; taux de réponse de 9 à 100 % par programme) et 67 % des directeurs de programme (8 sur 12). Au total, 41 étudiants en médecine canadiens (22 en préexternat [54 %], 2 étudiants au M.D./Ph. D. [5 %] et 17 stagiaires en formation clinique [41 %]) ont répondu au sondage. Les membres du comité ont considéré les critères suivants comme étant les plus importants dans le choix de candidats : le rendement clinique en service, l'entrevue, la qualité des lettres de recommandation de chirurgiens cardiaques et la réalisation d'un stage dans l'établissement associé au programme. En revanche, les critères suivants étaient considérés comme moins importants : le désir de pratiquer dans la ville ou la province de formation, un lien avec le lieu du programme, et la connaissance personnelle de membres du co-mité. Les perceptions des étudiants en médecine concordaient quant aux facteurs les plus importants, mais les étudiants surestimaient l'influence de facteurs non cliniques et de la productivité en recherche dans l'aspect concurrentiel de leur candidature. Conclusion: Les programmes de résidence canadiens en chirurgie cardiaque recherchent des candidats forts d'une excellence clinique, évaluée par les stages en chirurgie et les lettres de recommandation de collègues, et offrant une bonne performance en entrevue.