Transcatheter or Surgical Treatment of Aortic-Valve Stenosis.

BACKGROUND: Among low-risk patients with severe, symptomatic aortic stenosis who are eligible for both transcatheter aortic-valve implantation (TAVI) and surgical aortic-valve replacement (SAVR), data are lacking on the appropriate treatment strategy in routine clinical practice. METHODS: In this randomized noninferiority trial conducted at 38 sites in Germany, we assigned patients with severe aortic stenosis who were at low or intermediate surgical risk to undergo either TAVI or SAVR. Percutaneous- and surgical-valve prostheses were selected according to operator discretion. The primary outcome was a composite of death from any cause or fatal or nonfatal stroke at 1 year. RESULTS: A total of 1414 patients underwent randomization (701 to the TAVI group and 713 to the SAVR group). The mean (±SD) age of the patients was 74±4 years; 57% were men, and the median Society of Thoracic Surgeons risk score was 1.8% (low surgical risk). The Kaplan-Meier estimate of the primary outcome at 1 year was 5.4% in the TAVI group and 10.0% in the SAVR group (hazard ratio for death or stroke, 0.53; 95% confidence interval [CI], 0.35 to 0.79; P<0.001 for noninferiority). The incidence of death from any cause was 2.6% in the TAVI group and 6.2% in the SAVR group (hazard ratio, 0.43; 95% CI, 0.24 to 0.73); the incidence of stroke was 2.9% and 4.7%, respectively (hazard ratio, 0.61; 95% CI, 0.35 to 1.06). Procedural complications occurred in 1.5% and 1.0% of patients in the TAVI and SAVR groups, respectively. CONCLUSIONS: Among patients with severe aortic stenosis at low or intermediate surgical risk, TAVI was noninferior to SAVR with respect to death from any cause or stroke at 1 year. (Funded by the German Center for Cardiovascular Research and the German Heart Foundation; DEDICATE-DZHK6 ClinicalTrials.gov number, NCT03112980.).

Concomitant Tricuspid Repair in Patients with Degenerative Mitral Regurgitation.

BACKGROUND: Tricuspid regurgitation is common in patients with severe degenerative mitral regurgitation. However, the evidence base is insufficient to inform a decision about whether to perform tricuspid-valve repair during mitral-valve surgery in patients who have moderate tricuspid regurgitation or less-than-moderate regurgitation with annular dilatation. METHODS: We randomly assigned 401 patients who were undergoing mitral-valve surgery for degenerative mitral regurgitation to receive a procedure with or without tricuspid annuloplasty (TA). The primary 2-year end point was a composite of reoperation for tricuspid regurgitation, progression of tricuspid regurgitation by two grades from baseline or the presence of severe tricuspid regurgitation, or death. RESULTS: Patients who underwent mitral-valve surgery plus TA had fewer primary-end-point events than those who underwent mitral-valve surgery alone (3.9% vs. 10.2%) (relative risk, 0.37; 95% confidence interval [CI], 0.16 to 0.86; P = 0.02). Two-year mortality was 3.2% in the surgery-plus-TA group and 4.5% in the surgery-alone group (relative risk, 0.69; 95% CI, 0.25 to 1.88). The 2-year prevalence of progression of tricuspid regurgitation was lower in the surgery-plus-TA group than in the surgery-alone group (0.6% vs. 6.1%; relative risk, 0.09; 95% CI, 0.01 to 0.69). The frequencies of major adverse cardiac and cerebrovascular events, functional status, and quality of life were similar in the two groups at 2 years, although the incidence of permanent pacemaker implantation was higher in the surgery-plus-TA group than in the surgery-alone group (14.1% vs. 2.5%; rate ratio, 5.75; 95% CI, 2.27 to 14.60). CONCLUSIONS: Among patients undergoing mitral-valve surgery, those who also received TA had a lower incidence of a primary-end-point event than those who underwent mitral-valve surgery alone at 2 years, a reduction that was driven by less frequent progression to severe tricuspid regurgitation. Tricuspid repair resulted in more frequent permanent pacemaker implantation. Whether reduced progression of tricuspid regurgitation results in long-term clinical benefit can be determined only with longer follow-up. (Funded by the National Heart, Lung, and Blood Institute and the German Center for Cardiovascular Research; ClinicalTrials.gov number, NCT02675244.).

Toll-Like Receptor 3 Mediates Aortic Stenosis Through a Conserved Mechanism of Calcification.

BACKGROUND: Calcific aortic valve disease (CAVD) is characterized by a phenotypic switch of valvular interstitial cells to bone-forming cells. Toll-like receptors (TLRs) are evolutionarily conserved pattern recognition receptors at the interface between innate immunity and tissue repair. Type I interferons (IFNs) are not only crucial for an adequate antiviral response but also implicated in bone formation. We hypothesized that the accumulation of endogenous TLR3 ligands in the valvular leaflets may promote the generation of osteoblast-like cells through enhanced type I IFN signaling. METHODS: Human valvular interstitial cells isolated from aortic valves were challenged with mechanical strain or synthetic TLR3 agonists and analyzed for bone formation, gene expression profiles, and IFN signaling pathways. Different inhibitors were used to delineate the engaged signaling pathways. Moreover, we screened a variety of potential lipids and proteoglycans known to accumulate in CAVD lesions as potential TLR3 ligands. Ligand-receptor interactions were characterized by in silico modeling and verified through immunoprecipitation experiments. Biglycan (Bgn), Tlr3, and IFN-α/ß receptor alpha chain (Ifnar1)-deficient mice and a specific zebrafish model were used to study the implication of the biglycan (BGN)-TLR3-IFN axis in both CAVD and bone formation in vivo. Two large-scale cohorts (GERA [Genetic Epidemiology Research on Adult Health and Aging], n=55 192 with 3469 aortic stenosis cases; UK Biobank, n=257 231 with 2213 aortic stenosis cases) were examined for genetic variation at genes implicated in BGN-TLR3-IFN signaling associating with CAVD in humans. RESULTS: Here, we identify TLR3 as a central molecular regulator of calcification in valvular interstitial cells and unravel BGN as a new endogenous agonist of TLR3. Posttranslational BGN maturation by xylosyltransferase 1 (XYLT1) is required for TLR3 activation. Moreover, BGN induces the transdifferentiation of valvular interstitial cells into bone-forming osteoblasts through the TLR3-dependent induction of type I IFNs. It is intriguing that Bgn-/-, Tlr3-/-, and Ifnar1-/- mice are protected against CAVD and display impaired bone formation. Meta-analysis of 2 large-scale cohorts with >300 000 individuals reveals that genetic variation at loci relevant to the XYLT1-BGN-TLR3-interferon-α/ß receptor alpha chain (IFNAR) 1 pathway is associated with CAVD in humans. CONCLUSIONS: This study identifies the BGN-TLR3-IFNAR1 axis as an evolutionarily conserved pathway governing calcification of the aortic valve and reveals a potential therapeutic target to prevent CAVD.

Gene expression networks in endothelial cells from failing human hearts.

Chronic heart failure is associated with adverse remodeling of the heart that is typically characterized by cardiomyocyte hypertrophy. This requires the formation of new capillaries to maintain oxygen supply. Insufficient angiogenesis promotes the transition from compensated hypertrophy into heart failure. The aim of this study was to identify angiogenesis-related gene networks and corresponding regulatory hubs in endothelial cells from failing human hearts. We isolated left ventricular endothelial cells from patients with advanced heart failure undergoing left ventricular assist device surgery (n = 15) and healthy organ donors (n = 2) and performed RNA sequencing. Subgroup analysis revealed no impact of comorbidities on gene expression. In a weighted gene coexpression network analysis, we found 26 gene clusters, of which 9 clusters showed a significant positive or negative correlation with the presence of heart failure. We identified the transcription factors CASZ1 (castor zinc finger 1), ZNF523 (zinc finger protein 523), and NFE2L1 (nuclear factor erythroid 2-related factor 1) as hub genes of a cluster related to angiogenesis. Knockdown of CASZ1, ZNF523, or NFE2L1 in human umbilical vein endothelial cells led to a downregulation of genes from the respective cluster, including CD34 and platelet-derived growth factor-ß, confirming their regulatory function. In conclusion, we assessed gene networks in endothelial cells and identified transcription factors CASZ1, ZNF532, and NFE2L1 as potential regulators of angiogenesis in failing human hearts. Our study provides insights into the transcriptional regulation of angiogenesis beyond the classical vascular endothelial growth factor signaling pathway.NEW & NOTEWORTHY Gene coexpression network analysis defined 26 gene clusters expressed in endothelial cells from failing human hearts. Transcription factors CASZ1, ZNF523, and NFE2L1 were identified as hub genes of a cluster related to angiogenesis. Knockdown of CASZ1, ZNF523, or NFE2L1 in human umbilical vein endothelial cells led to a downregulation of genes from the respective cluster, confirming their regulatory function. This provides insights into the transcriptional regulation of angiogenesis in heart failure beyond classical signaling pathways.

Direct intramyocardial injection of VEGF mRNA in patients undergoing coronary artery bypass grafting.

Vascular endothelial growth factor A (VEGF-A) has therapeutic cardiovascular effects, but delivery challenges have impeded clinical development. We report the first clinical study of naked mRNA encoding VEGF-A (AZD8601) injected into the human heart. EPICCURE (ClinicalTrials.gov: NCT03370887) was a randomized, double-blind study of AZD8601 in patients with left ventricular ejection fraction (LVEF) 30%-50% who were undergoing elective coronary artery bypass surgery. Thirty epicardial injections of AZD8601 (total 3 mg) or placebo in citrate-buffered saline were targeted to ischemic but viable myocardial regions mapped using quantitative [15O]-water positron emission tomography. Seven patients received AZD8601 and four received placebo and were followed for 6 months. There were no deaths or treatment-related serious adverse events and no AZD8601-associated infections, immune reactions, or arrhythmias. Exploratory outcomes indicated potential improvement in LVEF, Kansas City Cardiomyopathy Questionnaire scores, and N-terminal pro-B-type natriuretic peptide levels, but the study is limited in size, and significant efficacy conclusions are not possible from the dataset. Naked mRNA without lipid encapsulation may provide a safe delivery platform for introducing genetic material to cardiac muscle, but further studies are needed to confirm efficacy and safety in a larger patient pool.

Beyond the Heartbeat: Single-Cell Omics Redefining Cardiovascular Research.

PURPOSE OF REVIEW: This review aims to explore recent advances in single-cell omics techniques as applied to various regions of the human heart, illuminating cellular diversity, regulatory networks, and disease mechanisms. We examine the contributions of single-cell transcriptomics, genomics, proteomics, epigenomics, and spatial transcriptomics in unraveling the complexity of cardiac tissues. RECENT FINDINGS: Recent strides in single-cell omics technologies have revolutionized our understanding of the heart's cellular composition, cell type heterogeneity, and molecular dynamics. These advancements have elucidated pathological conditions as well as the cellular landscape in heart development. We highlight emerging applications of integrated single-cell omics, particularly for cardiac regeneration, disease modeling, and precision medicine, and emphasize the transformative potential of these technologies to advance cardiovascular research and clinical practice.

Incidence of Prosthesis-Patient Mismatch in Valve-in-Valve with a Supra-Annular Valve.

BACKGROUND: Transcatheter aortic valve replacement (TAVR) for a degenerated surgical bioprosthesis (valve-in-valve [ViV]) has become an established procedure. Elevated gradients and patient-prosthesis mismatch (PPM) have previously been reported in mixed TAVR cohorts. We analyzed our single-center experience using the third-generation self-expanding Medtronic Evolut R prosthesis, with an emphasis on the incidence and outcomes of PPM. METHODS: This is a retrospective analysis of prospectively collected data from our TAVR database. Intraprocedural and intrahospital outcomes are reported. RESULTS: Eighty-six patients underwent ViV-TAVR with the Evolut R prosthesis. Mean age was 75.5 ± 9.5 years, 64% were males. The mean log EuroScore was 21.6 ± 15.7%. The mean time between initial surgical valve implantation and ViV-TAVR was 8.8 ± 3.2 years. The mean true internal diameter of the implanted surgical valves was 20.9 ± 2.2 mm. Post-AVR, 60% had no PPM, 34% had moderate PPM, and 6% had severe PPM. After ViV-TAVR, 33% had no PPM, 29% had moderate, and 39% had severe PPM. After implantation, the mean transvalvular gradient was reduced significantly from 36.4 ± 15.2 to 15.5 ± 9.1 mm Hg (p < 0.001). No patient had more than mild aortic regurgitation after ViV-TAVR. No conversion to surgery was necessary. Estimated Kaplan-Meier survival at 1 year for all patients was 87.4%. One-year survival showed no significant difference according to post-ViV PPM groups (p = 0.356). CONCLUSION: ViV-TAVR using a supra-annular valve resulted in low procedural and in-hospital complication rates. However, moderate or severe PPM was common, with no influence on short-term survival. PPM may not be a suitable factor to predict survival after ViV-TAVR.

Sequential Defects in Cardiac Lineage Commitment and Maturation Cause Hypoplastic Left Heart Syndrome.

BACKGROUND: Complex molecular programs in specific cell lineages govern human heart development. Hypoplastic left heart syndrome (HLHS) is the most common and severe manifestation within the spectrum of left ventricular outflow tract obstruction defects occurring in association with ventricular hypoplasia. The pathogenesis of HLHS is unknown, but hemodynamic disturbances are assumed to play a prominent role. METHODS: To identify perturbations in gene programs controlling ventricular muscle lineage development in HLHS, we performed whole-exome sequencing of 87 HLHS parent-offspring trios, nuclear transcriptomics of cardiomyocytes from ventricles of 4 patients with HLHS and 15 controls at different stages of heart development, single cell RNA sequencing, and 3D modeling in induced pluripotent stem cells from 3 patients with HLHS and 3 controls. RESULTS: Gene set enrichment and protein network analyses of damaging de novo mutations and dysregulated genes from ventricles of patients with HLHS suggested alterations in specific gene programs and cellular processes critical during fetal ventricular cardiogenesis, including cell cycle and cardiomyocyte maturation. Single-cell and 3D modeling with induced pluripotent stem cells demonstrated intrinsic defects in the cell cycle/unfolded protein response/autophagy hub resulting in disrupted differentiation of early cardiac progenitor lineages leading to defective cardiomyocyte subtype differentiation/maturation in HLHS. Premature cell cycle exit of ventricular cardiomyocytes from patients with HLHS prevented normal tissue responses to developmental signals for growth, leading to multinucleation/polyploidy, accumulation of DNA damage, and exacerbated apoptosis, all potential drivers of left ventricular hypoplasia in absence of hemodynamic cues. CONCLUSIONS: Our results highlight that despite genetic heterogeneity in HLHS, many mutations converge on sequential cellular processes primarily driving cardiac myogenesis, suggesting novel therapeutic approaches.

Uncovering the molecular identity of cardiosphere-derived cells (CDCs) by single-cell RNA sequencing.

Cardiosphere-derived cells (CDCs) generated from human cardiac biopsies have been shown to have disease-modifying bioactivity in clinical trials. Paradoxically, CDCs' cellular origin in the heart remains elusive. We studied the molecular identity of CDCs using single-cell RNA sequencing (sc-RNAseq) in comparison to cardiac non-myocyte and non-hematopoietic cells (cardiac fibroblasts/CFs, smooth muscle cells/SMCs and endothelial cells/ECs). We identified CDCs as a distinct and mitochondria-rich cell type that shared biological similarities with non-myocyte cells but not with cardiac progenitor cells derived from human-induced pluripotent stem cells. CXCL6 emerged as a new specific marker for CDCs. By analysis of sc-RNAseq data from human right atrial biopsies in comparison with CDCs we uncovered transcriptomic similarities between CDCs and CFs. By direct comparison of infant and adult CDC sc-RNAseq data, infant CDCs revealed GO-terms associated with cardiac development. To analyze the beneficial effects of CDCs (pro-angiogenic, anti-fibrotic, anti-apoptotic), we performed functional in vitro assays with CDC-derived extracellular vesicles (EVs). CDC EVs augmented in vitro angiogenesis and did not stimulate scarring. They also reduced the expression of pro-apoptotic Bax in NRCMs. In conclusion, CDCs were disclosed as mitochondria-rich cells with unique properties but also with similarities to right atrial CFs. CDCs displayed highly proliferative, secretory and immunomodulatory properties, characteristics that can also be found in activated or inflammatory cell types. By special culture conditions, CDCs earn some bioactivities, including angiogenic potential, which might modify disease in certain disorders.

Stroke after transcatheter aortic valve replacement: A severe complication with low predictability.

OBJECTIVES: We aimed to describe stroke and transient ischemic attacks (TIAs) after transcatheter aortic valve replacement (TAVR) and to identify associated risk factors. BACKGROUND: Stroke/TIA after TAVR is a major complication. METHODS: A total of 1919 concomitant patients underwent TAVR in a single center from 2007 to 2017. Pre-, intra-, and postprocedural data were collected prospectively in a database and analyzed retrospectively. Stroke and TIA were documented according to the Valve Academic Research Consortium-II criteria. Logistic regression was used to determine risk factors for stroke after TAVR. RESULTS: Mean age was 79.5 ± 6.8 years, mean logistic EuroScore was 17.6% ± 12.8%, and 51.8% (n = 994) of the patients were female. Stroke/TIA occurred in 76 patients (3.9%), 1.9% were disabling, and 1.6% nondisabling. The predominant type of stroke were territorial ischemic lesions (82.4%), with primary bleeding in 4.4% and border zone infarctions in 4.4%. Left-sided lesions were more common (45.6% left sided vs. 25% right sided) and 13.2% of the lesions were bilateral (4.4% no finding and 11.8% missing data). In multivariate logistic regression, prior stroke (odds ratio [OR] = 1.83, p = 0.046) and initial experience (first 300 TAVR implanted at our center) were identified as independent risk factors for stroke/TIA during the first 30 days (OR = 1.95, p = 0.045). Overall, the occurrence of stroke had a highly significant impact on a 30-day mortality (13.2% vs. 4.9% in patients without stroke (p = 0.005). CONCLUSION: Stroke within the first 30 days after TAVR severely impairs 30-day survival. We identified prior stroke and initial experience as significant independent risk factors for the occurrence of stroke after TAVR.

Aortic valve neocuspidization: Frequently asked technical questions.

Since the first description by Professor Ozaki in 2011, more than 5500 aortic valve neocuspidization procedures have been performed worldwide, with promising short- and mid-term outcomes. We here report the nuances required to master this highly reproducible, standardized technique for the treatment of aortic valve disease.

Aortic valve neocuspidization using autologous pericardium compared to surgical aortic valve replacement.

INTRODUCTION: Aortic valve neocuspidization (AVNeo) for trileaflet aortic valve reconstruction using autologous pericardium (Ozaki procedure) depicts an encouraging new technique for the surgical treatment of aortic valve pathologies. The current study analyzes the early hemodynamic outcome of AVneo compared with surgical aortic valve replacement (SAVR) using the Abbott/St. Jude Trifecta aortic valve biological prostheses. METHODS: All patients who underwent either AVNeo or SAVR between March 2017 and April 2020 were included. Exclusion criteria were emergency cases, endocarditis, redo- or additional root procedures. Main endpoints were differences between the two groups in terms of the effective orifice area (EOA) and the effective orifice area index (EOAI) at discharge. RESULTS: During the study period, 105 AVNeo patients and 458 SAVR patients met the inclusion criteria. EOA was significantly higher in the AVNeo group (2.4 cm2 ± 0.8 vs. 2.1 cm2 /m2 ± 0.6 in the SAVR group, respectively; p < .001). Multiple regression analysis, including AVNeo, annulus size, bicuspid valve, preoperative stenosis, left ventricular ejection fraction (LVEF), and diastolic diameter (LVEDD) found two factors, which favor larger EOA: Annulus size (p < .0001) and AVneo (p = .005). EOAI was significantly higher in the AVNeo group (1.23 ± 0.4 vs. 1.02 cm2 /m2 ± 0.3, respectively; p < .001). Multiple regression analysis for EOAI showed effects for AVneo (p = .005) and bicuspid valve (p = .029). Mean pressure gradients (MPG) were lower in the AVNeo group than in the SAVR group (AVNeo: MPG = 8.0 mmHg ± 3.6 vs. SAVR: MPG = 8.3 mmHg ± 3.6), but this finding did not reach statistical significance (p = .091). CONCLUSIONS: AVNeo shows significantly larger EOA and EOAI compared to SAVR using the Abbott/St. Jude Trifecta aortic valve biological prostheses.

Midterm outcomes of mitral valve repair versus replacement in elderly patients: A propensity score-matched analysis.

BACKGROUND: Current literature reports better short-term mortality rates in mitral valve repair over replacement in elderly patients. However, valve durability, postoperative complications, and reintervention rates in these cohorts remain understudied. As such, we aimed to investigate 5-year rates of mortality and reoperation after initial mitral repair or replacement in elderly patients. METHODS: Using the TriNetX Research Network database, we identified patients aged ≥70 who underwent mitral valve repair or replacement for nonrheumatic mitral insufficiency between January 2010 and December 2020. We 1:1 propensity score-matched cohorts for 33 covariates including demographics, comorbidities, and surgical history. After matching, we compared 5-year mortality and reoperation rates between cohorts using Kaplan-Meier estimates and multivariable Cox proportional hazards models. RESULTS: We compared 823 mitral valve repair patients to a propensity score-matched cohort of 823 mitral valve replacement patients over a 5-year follow-up period. All variables of interest were adequately matched. Cumulative 5-year mortality rate was significantly lower among mitral valve repair patients (17.0% vs. 24.9%; hazard ratio [HR]: 0.66, 95% confidence interval [95% CI]: 0.51-0.87, p < 0.0025). Reoperation rates at 5-year did not differ (2.6% vs. 2,1%; HR: 1.34, 95% CI: 0.67-2.68, p = 0.401). CONCLUSIONS: We observed lower 5-year mortality rates and nonsignificantly different reoperation rates among elderly patients with mitral regurgitation undergoing mitral valve repair compared to replacement. Our data support the current understanding that mitral valve repair should be considered as the first treatment line whenever possible, even in elderly patients.

Surgical treatment of isolated tricuspid valve endocarditis: Midterm data.

BACKGROUND: Isolated tricuspid valve endocarditis (TVE) is a rare disease which is managed medically in most patients. Only in specific cases, surgical intervention becomes necessary. Hence, data about surgical outcomes are sparse. This study reports on the operative experience in patients with isolated TVE over a period of 20 years. METHODS: We retrospectively analyzed 32 patients with isolated TVE who underwent surgery from February 2001 to June 2021 at the German Heart Centre Munich. RESULTS: Thirty-day mortality was 3.1%. Overall survival was 89.9± 5.5% at 1 year and 76.9 ± 8.5% at 5 years. Cumulative incidence for reoperation was 11.1 ± 6.0% at 5 years. Four patients (12.5%) were treated for recurrent endocarditis. Tricuspid valve repair (TVr) was achieved in 16 patients (50%). If the subvalvular apparatus (n = 10) was involved, tricuspid valve replacement was performed more frequently. CONCLUSIONS: Mortality in patients with isolated TVE undergoing cardiac surgery is high. In half of the cases, TVr was achieved but was less likely in patients with affected subvalvular apparatus.

Variable definitions and treatment approaches for atrial functional mitral regurgitation: A scoping review of the literature.

OBJECTIVES: Atrial functional mitral regurgitation (AFMR) is a subtype of functional mitral regurgitation due to longstanding atrial fibrillation (AF) or heart failure with preserved ejection fraction. The variation in AFMR' definition and the common mode of treatment described in the literature remain unknown. METHODS: We performed a scoping review of studies that surgically treated AFMR to characterize the existing variability in the definition of AFMR, the type of operations performed for AFMR valvulopathy, and the treatment for the chronic AF. We searched Medline, EMBASE, Cochrane Library, Scopus, and Web of Science since their inceptions for studies of patients affected by AFMR and surgically treated for their valvulopathy. RESULTS: Twelve studies (n = 494 patients) met eligibility criteria. All studies excluded patients with signs of left ventricular (LV) dysfunction, but the way additional parameters were used to define AFMR at a more granular level varied across studies: nine studies (75%) used the presence of AF to define their AFMR cohorts, with five (41.2%) requiring a history of AF of >1 year; additionally, the threshold values for the LV ejection fraction differed (45%-55%). Isolated mitral annuloplasty was performed in 96.2% of patients. Broad variability was detected in the proportion of patients undergoing the Cox-Maze procedure (range, 17.8%-79.5%), pulmonary vein isolation (0.0%-66.7%), and left atrial appendage ligation (0.0%-100.0%). CONCLUSIONS: AFMR remains variably defined in surgical studies, making comparisons across studies difficult. Mitral annuloplasty was most commonly performed. The proportion of AFMR patients undergoing concomitant procedures for AF varied substantially.

Institution representation in publications reporting mitral valve repair durability: A scoping review.

BACKGROUND: Mitral valve repair durability currently plays a key role in operative decision making and in defining optimal surgical practice. However, mitral valve durability outcomes measures are not captured by national registries and limited to centers that publish their outcomes. In this study, we aim to describe the scope of institutions represented by reports describing durability outcomes after mitral valve repair within the contemporary literature. METHODS AND RESULTS: A scoping review of the literature was performed to extract abstracts potentially reporting mitral valve operation outcomes published between 2000-2019. 370 full text articles reporting mitral valve durability outcomes by either reoperation rate or rate of recurrent mitral regurgitation met criteria for analysis. Study characteristics including case volume, country and institution of origin, and surgeon volume were extracted and used to calculate the proportion of total cases in the top 3, 5, and 10 represented countries and institutions by the sum of reported mitral valve repairs described. The top 5 of 21 countries represented 78.9% of the mitral valve repair cases described. The top 3 most represented institutions described 20,120 (37.3%) of all mitral valve repairs in 58 (33.9%) single-center studies. CONCLUSION: Published mitral valve repair durability data must be interpreted with caution when used to derive policies and practice recommendations that govern the cardiovascular community at large.

Direct relationship between transvalvular velocity and cardiac dysfunction, morbidity, and mortality in patients with aortic stenosis.

OBJECTIVE: Current guidelines recommend intervention in subjects with severe symptomatic aortic stenosis (AS), even though any degree of AS is associated with a higher risk of mortality. We investigated the association between the degree of AS, delineated by transvalvular flow velocity, and patient morbidity and mortality. METHODS: Medically managed patients aged 40-95 years with maximum flow velocity (Vmax ) by echocardiography between 2013 and 2018 were stratified into five groups (A-E) based on the 75th, 90th, 97.5th, and the 99th percentiles of Vmax distribution. Patient characteristics, cardiac structural changes, and end-organ disease were compared using Kruskal-Wallis and Cochran-Armitage tests. Mortality over a median of 2.8 (1.52-4.8) years was compared using Kaplan-Meier curves and risk estimates were derived from the Cox model. RESULTS: The Vmax was reported in 37,131 patients. There was a steady increase (from Group A towards E) in age, Caucasian race, structural cardiac changes, end-organ morbidities, and all-cause mortality. In reference to Group A, there as an increased risk of mortality in Groups B (hazard ratio [HR] = 1.3; confidence interval [CI]: 1.2-1.35; p < .0001), C (HR = 1.5; CI: 1.4-1.6; p < .0001), and D (HR = 1.8; CI: 1.6-2; p < .0001), with an exponential increase in Group E (HR = 2.5; CI: 2.2-2.8; p < .0001). CONCLUSIONS: A direct, strong correlation exists between the degree of AS and cardiac structural changes and mortality. Patients with Vmax ≥ 97.5th percentile (≥3.2 m/s) might benefit from early intervention.

Acute mental stress drives vascular inflammation and promotes plaque destabilization in mouse atherosclerosis.

AIMS: Mental stress substantially contributes to the initiation and progression of human disease, including cardiovascular conditions. We aim to investigate the underlying mechanisms of these contributions since they remain largely unclear. METHODS AND RESULTS: Here, we show in humans and mice that leucocytes deplete rapidly from the blood after a single episode of acute mental stress. Using cell-tracking experiments in animal models of acute mental stress, we found that stress exposure leads to prompt uptake of inflammatory leucocytes from the blood to distinct tissues including heart, lung, skin, and, if present, atherosclerotic plaques. Mechanistically, we found that acute stress enhances leucocyte influx into mouse atherosclerotic plaques by modulating endothelial cells. Specifically, acute stress increases adhesion molecule expression and chemokine release through locally derived norepinephrine. Either chemical or surgical disruption of norepinephrine signalling diminished stress-induced leucocyte migration into mouse atherosclerotic plaques. CONCLUSION: Our data show that acute mental stress rapidly amplifies inflammatory leucocyte expansion inside mouse atherosclerotic lesions and promotes plaque vulnerability.

Proximity to injury, but neither number of nuclei nor ploidy define pathological adaptation and plasticity in cardiomyocytes.

The adult mammalian heart consists of mononuclear and binuclear cardiomyocytes (CMs) with various ploidies. However, it remains unclear whether a variation in ploidy or number of nuclei is associated with distinct functions and injury responses in CMs, including regeneration. Therefore, we investigated transcriptomes and cellular as well as nuclear features of mononucleated and binucleated CMs in adult mouse hearts with and without injury. To be able to identify the role of ploidy we analyzed control and failing human ventricular CMs because human CMs show a larger and disease-sensitive degree of polyploidization. Using transgenic Myh6-H2BmCh to identify mononucleated and binucleated mouse CMs, we found that cellular volume and RNA content were similar in both. On average nuclei of mononuclear CMs showed a 2-fold higher ploidy, as compared to binuclear CMs indicating that most mononuclear CMs are tetraploid. After myocardial infarction mononucleated and binucleated CMs in the border zone of the lesion responded with hypertrophy and corresponding changes in gene expression, as well as a low level of induction of cell cycle gene expression. Human CMs allowed us to study a wide range of polyploidy spanning from 2n to 16n. Notably, basal as well as pathological gene expression signatures and programs in failing CMs proved to be independent of ploidy. In summary, gene expression profiles were induced in proximity to injury, but independent of number of nuclei or ploidy levels in CMs.

Agrin Promotes Coordinated Therapeutic Processes Leading to Improved Cardiac Repair in Pigs.

BACKGROUND: Ischemic heart diseases are leading causes of death and reduced life quality worldwide. Although revascularization strategies significantly reduce mortality after acute myocardial infarction (MI), a large number of patients with MI develop chronic heart failure over time. We previously reported that a fragment of the extracellular matrix protein agrin promotes cardiac regeneration after MI in adult mice. METHODS: To test the therapeutic potential of agrin in a preclinical porcine model, we performed ischemia-reperfusion injuries using balloon occlusion for 60 minutes followed by a 3-, 7-, or 28-day reperfusion period. RESULTS: We demonstrated that local (antegrade) delivery of recombinant human agrin to the infarcted pig heart can target the affected regions in an efficient and clinically relevant manner. A single dose of recombinant human agrin improved heart function, infarct size, fibrosis, and adverse remodeling parameters 28 days after MI. Short-term MI experiments along with complementary murine studies revealed myocardial protection, improved angiogenesis, inflammatory suppression, and cell cycle reentry as agrin's mechanisms of action. CONCLUSIONS: A single dose of agrin is capable of reducing ischemia-reperfusion injury and improving heart function, demonstrating that agrin could serve as a therapy for patients with acute MI and potentially heart failure.