Improved Hemodynamics With Self-Expanding Compared to Balloon-Expandable Transcatheter Aortic Valve Implantation in Small Annulus Patients: A Propensity-Matched Analysis.

Patients with small aortic annuli (SAA) pose a challenge in patients undergoing aortic valve replacement because of the potential for prosthesis-patient mismatch (PPM). This study aimed to compare the clinical and hemodynamic outcomes of self-expandable valve (SEV) versus balloon-expandable valve (BEV) transcatheter aortic valve implantation (TAVI) in patients with severe aortic stenosis and SAA. All patients who underwent TAVI for severe native aortic stenosis with a SAA between January 2018 and December 2022 were retrospectively included in the study from a single center. Propensity score matching was performed to balance the baseline characteristics. Bioprosthesis valve dysfunction was based on modified Valve Academic Research Consortium 3 criteria. A total of 1,170 TAVI procedures were performed between 2018 and 2022. After applying the exclusion criteria, 332 patients reported a SAA at computed tomography scan, and the matching created 109 balanced pairs. Echocardiographic data at discharge showed higher mean transvalvular gradients (p <0.001), higher grades of mitral regurgitation (p = 0.029), and lower ejection fraction (p <0.043) in BEVs than SEVs. At follow-up, significant differences favoring the SEV group regarding bioprosthesis valve dysfunction were observed (p = 0.002), especially in terms of severe PPM (p = 0.046) and at least moderate structural valve deterioration (p = 0.040). In conclusion, TAVI in patients with SAA using a BEV was associated with lower valve areas, higher mean pressure gradients, and PPM (including severe) than a SEV. Short- and midterm all-cause and cardiac-related mortality did not differ between the 2 groups. Future randomized studies with extended follow-ups are warranted to validate these outcomes.

Direct aortic cannulation versus femoral arterial cannulation for early outcomes in acute type A aortic dissection: A study-level meta-analysis.

PURPOSE: To investigate the impact of direct aortic cannulation (DAC) versus femoral arterial cannulation (FAC) on clinical outcomes of surgery for acute type A aortic dissection. METHODS: PubMed/MEDLINE, Scopus, and Cochrane Central Register of Controlled Trials were searched until August 25, 2023, to conduct a meta-analysis. Primary endpoints of the study were operative mortality and postoperative stroke. Secondary endpoints were cardiopulmonary bypass time, myocardial ischemic time, hypothermic circulatory arrest time, temporary neurological dysfunction (TND), combined stroke and TND, re-exploration for bleeding, and need for renal replacement therapy. A random-effect model was used to estimate the pooled effect size, and a leave-one-out method was used for the primary endpoints for sensitivity analysis. RESULTS: 15 studies met our eligibility criteria, including a total of 7941 samples. Operative mortality was significantly lower in the DAC group with a pooled odds ratio (OR) of 0.72 [95% confidence interval (CI): 0.61-0.85)]. Incidence of postoperative stroke was also lower in the DAC group with a pooled OR of 0.79 (95% CI: 0.66-0.94). However, after excluding one study with the greatest weight, the difference became nonsignificant. DAC was also associated with a lower incidence of postoperative TND, and re-exploration for bleeding with a pooled OR of 0.52 (95% CI: 0.37-0.73), and 0.60 (95% CI: 0.47-0.77), respectively. CONCLUSIONS: This meta-analysis showed that patients who underwent ATAAD repair with DAC had a lower incidence of operative mortality, postoperative stroke, TND, and re-exploration for bleeding compared to those who underwent FAC.

Clinical and Echocardiographic Outcomes of Patients Undergoing Transcatheter Edge-to-Edge Repair for Functional vs Degenerative Mitral Valve Regurgitation.

To analyze clinical and echocardiographic outcomes after transcatheter edge-to-edge repair (TEER) with mitral valve clip device (MitraClip-TM) for functional vs degenerative mitral valve regurgitation (MR). All consecutive 185 patients undergoing TEER between January 2019 and March 2023 were included in the study. A propensity-adjusted analysis investigated differences among functional vs degenerative MR mechanism groups. Preoperatively, functional vs degenerative MR included 43 vs 142 patients, respectively. Mean ejection fraction (EF) values were 37% vs 57.8%, mean STS-PROM risk score was 7% vs 4% while patients with severe MR included 29 (67.4%) vs 129 (90.9%) patients, respectively. Postoperatively, functional MR patients experienced a higher incidence of prolonged postoperative length of stay (LOS), reduced creatinine clearance, and EF<50% compared to the degenerative MR group. Mean EF was 35.9% vs 56.2% (P < 0.0001) and 1 (2.3%) vs 16 (11.3%) patients had residual severe MR (P = 0.01) in functional vs degenerative MR groups, respectively. At 30-days follow-up, all-cause death incidence was 1 (2.3%) vs 3 (2.1%) patients in functional vs degenerative MR, respectively (P = 0.9). At a mean of 1.6-years follow-up, all-cause death (P = 0.01), major adverse cardiovascular and cerebrovascular events (MACCE) (P = 0.02), cardiac death (P = 0.01) and hazard ratio for all-cause death higher in functional vs degenerative MR group. Mean EF was 39.7% vs 56% (P < 0.001) while residual severe MR was 4 (9.3%) vs 34 (24.5%) (P = 0.1) in functional vs degenerative MR groups, respectively. TEER with MitraClip device showed a higher incidence of all-cause death, cardiac death, and MACCE at follow-up for functional compared to degenerative MR after TEER.

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.

Postoperative Nosocomial COVID-19 Infection in Cardiac Surgery: An Uncommon Event With High Mortality Rate.

BACKGROUND: The COVID-19 pandemic has had a major impact on cardiac surgery patients. Significant reductions in access to surgical treatment have forced surgeons to prioritise patients and follow strict COVID-19 protocols to protect surgeons, staff, and patients. Adult cardiac surgery and the COVID-19 pandemic: aggressive infection mitigation strategies are necessary in the operating room and surgical recovery. Nosocomial infections among cardiac surgery patients have been reported and are associated with a high mortality rate. As a COVID-19 tertiary care centre and a tertiary cardiac centre, we tried to balance the need to operate on urgent cardiac cases while protecting patients and staff from COVID-19. METHODS: During the first wave of the pandemic, we performed 579 surgeries. We report findings from an outbreak of 4 nosocomial infections. RESULTS: All patients tested negative within 24 hours of surgery or admission. Three patients were positive after surgery, suggesting an overall nosocomial rate during the first wave of 0.5% (3/579). One patient admitted for evaluation tested positive during mass screening. Two of the 4 patients died after respiratory complications. No health care worker (HCW) or family member with direct contact with these patients tested positive for COVID-19. Nosocomial COVID-19 infection is uncommon when adhering to safety protocols. Although uncommon, the mortality rate is high (50%) in our series. CONCLUSIONS: As widespread vaccination of HCWs and high-risk individuals susceptible to COVID-19 is in progress, we suggest that cardiac surgery patients, when feasible, be vaccinated before surgery given this could prevent excess mortality, protect HCWs and reduce resource use.

CONTEXTE: La pandémie de COVID-19 a eu des répercussions importantes sur les patients en chirurgie cardiaque. Les réductions importantes de l'accès aux traitements chirurgicaux ont obligé les chirurgiens à classer les patients par ordre de priorité et à suivre des protocoles COVID-19 rigoureux pour protéger les chirurgiens, le personnel et les patients. En ce qui a trait à la chirurgie cardiaque chez les adultes pendant la pandémie de COVID-19, des stratégies énergiques d'atténuation des infections sont nécessaires en salle d'opération et pendant la convalescence. Des infections nosocomiales ont été signalées chez des patients de chirurgie cardiaque; elles sont associées à un taux de mortalité élevé. Comme notre centre de soins tertiaires traite à la fois des patients atteints de troubles cardiaques et des patients atteints de la COVID-19, nous avons essayé de trouver un équilibre entre la nécessité d'effectuer les opérations cardiaques urgentes et la protection des patients et du personnel contre la COVID-19. MÉTHODOLOGIE: Pendant la première vague de la pandémie, nous avons effectué 579 interventions chirurgicales. Nous rapportons les résultats d'une éclosion de quatre infections nosocomiales. RÉSULTATS: Tous les patients ont obtenu un résultat négatif au test de dépistage dans les 24 heures suivant l'intervention ou l'admission. Trois patients ont obtenu un résultat positif à ce test après l'intervention, ce qui indique un taux global d'infection nosocomiale de 0,5 % (3 / 579) au cours de la première vague. Un patient admis pour évaluation a obtenu un résultat positif au moment du dépistage de masse. Deux des quatre patients sont morts après des complications respiratoires. Aucun travailleur de la santé ou membre de la famille ayant eu un contact direct avec ces patients n'a obtenu un résultat positif au test de dépistage de la COVID-19. L'infection nosocomiale à la COVID-19 est rare quand les protocoles de sécurité sont respectés. Mais même si elle est peu fréquente, le taux de mortalité associé est élevé (50 %) dans notre série. CONCLUSIONS: Alors que la vaccination généralisée des travailleurs de la santé et des personnes à haut risque vulnérables à la COVID-19 est en cours, nous suggérons que les patients en chirurgie cardiaque soient vaccinés avant l'opération, si possible, car cela pourrait prévenir la surmortalité, protéger les travailleurs de la santé et réduire l'utilisation des ressources.

Does adding an aortic root replacement or sinus repair during arch repair increase postoperative mortality? Evidence from the Canadian Thoracic Aortic Collaborative.

OBJECTIVES: The aim of this study was to examine the effect of the addition of an aortic root replacement or sinus repair on mortality and morbidity during aortic arch repair. METHODS: A total of 2472 patients underwent proximal or total aortic arch repair with hypothermic circulatory arrest between 2002 and 2018 at 12 centres. Multivariable logistic regressions (MV) and propensity score (PS) with inverse probability of treatment weighting (IPTW) analyses were performed. RESULTS: A total of 1099 (44.5%) patients had additional aortic root replacement (n = 934) or sinus repair (n = 165). Those with aortic root interventions were younger (61 ± 13 vs 64 ± 13 years, P < 0.001) and had less females (23% vs 35%, P < 0.001), less dissection (31% vs 36%, P = 0.004), less urgent cases (35% vs 39%, P = 0.047), more connective tissue disease (7% vs 3%, P < 0.001) and less total arch replacements (14% vs 22%, P < 0.001). On adjusted analyses, the addition of aortic root procedure was associated with increased mortality [MV: odds ratio (OR) 1.41, 95% confidence interval (CI) 1.03-1.92; PS-IPTW: risk increased by 3.7%, 95% CI 1.2-6.3%, P = 0.004]. Reoperation for bleeding was also increased with the addition of aortic root intervention (MV: OR 1.48, 95% 1.10-1.99; PS-IPTW: risk increased by 3.2%, 95% CI 0.8-5.6%, P = 0.009). The risks of stroke and dialysis-dependent renal failure were similar. When looking only at non-elective cases, the increased risk of mortality was more pronounced (MV: OR 1.60, 95% CI 1.11-2.32, P = 0.013; PS-IPTW: risk increased by 6.8%, 95 CI 1.7-11.8%, P = 0.008, and a number need to harm of 15 patients to cause 1 additional death). CONCLUSIONS: The addition of aortic root replacement or sinus repair during proximal or total aortic arch repair seems to increase postoperative mortality only in non-elective cases.

Early results of a modified biological valved conduit for the Bentall procedure.

INTRODUCTION: Few bioprosthetic valved conduits for aortic root surgery are commercially available. Long-term Warfarin therapy (mechanical), potential root calcification (xeno- or homograft valves), and the need for additional ascending aorta grafts are concerns associated with currently used valved conduits. A simplified, self-assembled bioroot conduit comprising currently available materials that facilitates future intervention and exhibits advantages of a bioprosthesis was used. METHODS: From November 2015 to January 2017, 17 consecutive patients underwent urgent or elective aortic root surgery. A bioroot conduit, constructed using 28 or 30 mm of sinus of Valsalva Gelweave tube graft and a 3 to 5 mm smaller bioprosthetic Trifecta valve sewn into the sinus of Valsalva base, was preconstructed in the operating room before sternotomy. The size of the valved conduit was based on the distal ascending aorta or proximal arch and not aortic annular dimension. The bioroot was sutured to the native aortic annulus at the level of the bottom skirt of the Valsalva graft without contacting the sewing cuff of the bioprosthetic valve. RESULTS: All patients survived the operation and were discharged home without long-term anticoagulation therapy. The mean age was 65 ± 12 years, and 13 patients were male. The cardiopulmonary bypass duration was 169 ± 84 minutes, and the cross-clamp (XC) duration was 110 ± 32 minutes. The operation was elective in 12 patients, urgent/emergent in five, and redo in three. CONCLUSION: A simplified self-assembled bioroot Bentall conduit is appropriate for aortic root reconstruction. Use of a patient-tailored valved conduit will not prolong the cardiac ischemic time and will facilitate future valve replacement.

A Tumor Necrosis Factor-α and Hypoxia-Induced Secretome Therapy for Myocardial Repair.

BACKGROUND: Poor viability and retention of transplanted bone marrow mesenchymal stem cells (BM-MSC) remains an obstacle in promoting healing after myocardial infarction (MI). This study aimed to understand the migratory, angiogenic, and cardioprotective effects induced by tumor necrosis factor (TNF)-α and hypoxia through rat BM-MSC (rBM-MSC) paracrine secretions, collectively referred to as secretome, after MI. METHODS: Secretome from rBM-MSC cultures treated with various combinations of H9c2 cardiomyoblast-conditioned medium, TNF-α, and hypoxia was initially collected. Immunocytochemistry, Western blot analyses, and transwell cell migration assays were conducted. In vivo, echocardiography was performed on rats with induced MI after their treatment with TNF-α and hypoxia-induced secretome. RESULTS: Immunocytochemistry confirmed the presence of TNF receptors 1 and 2 on rBM-MSCs. Western blot analyses of rBM-MSCs treated with TNF-α and hypoxia showed an overall increasing trend in the expression of antiinflammatory proteins and angiogenic and migratory cytokines (transforming growth factor-ß, fibroblast growth factor-2, angiopoietin-2, vascular endothelial growth factor-1). In addition, the TNF-α and hypoxia-induced secretome significantly increased the in vitro rBM-MSCs migration. In the rat MI model, the rats treated with the TNF-α and hypoxia-induced secretome had a significantly higher left ventricular fractional shortening than the control group. CONCLUSIONS: Our data suggest that after MI, rBM-MSCs secrete paracrine factors in response to TNF-α and hypoxia that work together to manipulate the microenvironment and decrease inflammation. In addition, these signaling factors trigger angiogenic and migratory effects at the site of the infarct to promote myocardial healing and improve the cardiac function.

Hypoxia modulates cell migration and proliferation in placenta-derived mesenchymal stem cells.

OBJECTIVES: For more than a decade, stem cells isolated from different tissues have been evaluated in cell therapy. Among them, the human bone marrow-derived mesenchymal stem cells (hBM-MSCs) were investigated extensively in the treatment of myocardial infarction. Recently, the human placenta-derived mesenchymal stem cells (hPD-MSCs), which are readily available from a biological waste, appear to be a viable alternative to hBM-MSCs. METHODS: C-X-C chemokine receptor type 4 (CXCR4) gene expression and localization were detected and validated in hPD-MSCs and hBM-MSCs via polymerase chain reaction and immunofluorescence. Subsequently, cell culture conditions for CXCR4 expression were optimized in stromal-derived factor-1 alpha (SDF1-α), glucose, and cobalt chloride (CoCl2) by the use of cell viability, proliferation, and migration assays. To elucidate the cell signaling pathway, protein expression of CXCR4, hypoxia-inducible factor-1α, interleukin-6, Akt, and extracellular signal-regulated kinase were analyzed by Western blot. CXCR4-positive cells were sorted and analyzed by florescence-activated cell sorting. RESULTS: CXCR4 was expressed on both hPD-MSCs and hBM-MSCs at the basal level. HPD-MSCs were shown to have a greater sensitivity to SDF-1α-dependent cell migration compared with hBM-MSCs. In addition, CXCR4 expression was significantly greater in both hPD-MSCs and hBM-MSCs with SDF-1α or CoCl2-induced hypoxia treatment. However, CXCR4+ hPD-MSCs population increased by 10-fold in CoCl2-induced hypoxia. In contrast, only a 2-fold increase was observed in the CXCR4+ hBM-MSCs population in similar conditions. After CoCl2-induced hypoxia, the CXCR4/mitogen-activated protein kinase kinase/extracellular signal-regulated kinase signaling pathway was activated prominently in hPD-MSCs, whereas in hBM-MSCs, the CXCR4/phosphatidylinositol 3-kinase/Akt pathway was triggered. CONCLUSIONS: Our current results suggest that hPD-MSCs could represent a viable and effective alternative to hBM-MSCs for translational studies in cardiocellular repair.

Conditioned medium of H9c2 triggers VEGF dependent angiogenesis by activation of p38/pSTAT3 pathways in placenta derived stem cells for cardiac repair.

AIMS: Cardiomyocytes are understood to possess a limited regenerative capacity. Any myocardial insult leads to an irreversible injury. Mesenchymal stem cell differentiation into cardiomyocyte-like cells stands as one of the leading experimental therapies. However, a candidate cell source has yet to be defined. Here, we examined the in vitro and in vivo cardiac differentiation potential of human placenta derived stem cells (hPDSCs); a unique, abundant, and non-immunogenic cell source. MAIN METHODS: H9c2 cell culture medium was applied to hPDSCs at different ratios for a period of 4weeks. In parallel, hPDSCs, human bone marrow stem cells, or cell free culture medium was injected in peri-infarcted regions induced in rat hearts. KEY FINDINGS: In vitro, hPDSCs pre-conditioned with H9c2 cell culture medium proportionally over-expressed alpha sarcoplasmic actinin and displaced connexin 43 from the cytoplasm to the cell membrane. Additionally, pre-conditioning promoted hPDSCs survival and triggered vascular endothelial growth factor (VEGF) dependent angiogenesis by activating the pAkt and p38MAPK/pSTAT3 pathways. In vivo, echocardiography analysis showed a significant improvement in cardiac parameters in the rats injected with hPDSCs, similar to the human bone marrow stem cells injected group. Moreover, hPDSCs detected within rat cardiac tissues expressed troponin I and myosin heavy chain. In accordance with the pre-conditioning findings, VEGF positive neovessels were observed in hearts injected with hPDSCs. SIGNIFICANCE: hPDSCs have the potential to differentiate into cardiac-like cells and induce angiogenesis via paracrine effects. With the advantages of easy availability and young age, these cells could be more suitable for clinical translation.

Cardiac tissue engineering and regeneration using cell-based therapy.

Stem cell therapy and tissue engineering represent a forefront of current research in the treatment of heart disease. With these technologies, advancements are being made into therapies for acute ischemic myocardial injury and chronic, otherwise nonreversible, myocardial failure. The current clinical management of cardiac ischemia deals with reestablishing perfusion to the heart but not dealing with the irreversible damage caused by the occlusion or stenosis of the supplying vessels. The applications of these new technologies are not yet fully established as part of the management of cardiac diseases but will become so in the near future. The discussion presented here reviews some of the pioneering works at this new frontier. Key results of allogeneic and autologous stem cell trials are presented, including the use of embryonic, bone marrow-derived, adipose-derived, and resident cardiac stem cells.