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Introduction: Microvascular dysfunction (MVD) is a hallmark feature of chronic graft dysfunction in patients that underwent orthotopic heart transplantation (OHT) and is the main contributor to impaired long-term graft survival. The aim of this study was to determine the effect of MVD on functional and structural properties of cardiomyocytes isolated from ventricular biopsies of OHT patients. Methods: We included 14 patients post-OHT, who had been transplanted for 8.1 years [5.0; 15.7 years]. Mean age was 49.6 ± 14.3 years; 64% were male. Coronary microvasculature was assessed using guidewire-based coronary flow reserve(CFR)/index of microvascular resistance (IMR) measurements. Ventricular myocardial biopsies were obtained and cardiomyocytes were isolated using enzymatic digestion. Cells were electrically stimulated and subcellular Ca2+ signalling as well as mitochondrial density were measured using confocal imaging. Results: MVD measured by IMR was present in 6 of 14 patients with a mean IMR of 53±10 vs. 12±2 in MVD vs. controls (CTRL), respectively. CFR did not differ between MVD and CTRL. Ca2+ transients during excitation-contraction coupling in isolated ventricular cardiomyocytes from a subset of patients showed unaltered amplitudes. In addition, Ca2+ release and Ca2+ removal were not significantly different between MVD and CTRL. However, mitochondrial density was significantly increased in MVD vs. CTRL (34±1 vs. 29±2%), indicating subcellular changes associated with MVD. Conclusion: In-vivo ventricular microvascular dysfunction post OHT is associated with preserved excitation-contraction coupling in-vitro, potentially owing to compensatory changes on the mitochondrial level or due to the potentially reversible cause of the disease. [ABSTRACT FROM AUTHOR]

Aims In patients with infections of cardiac implantable electronic devices (CIEDs), the identification of causative pathogens is complicated by biofilm formations and previous antibiotic therapy. In this work, the impact of an additional fluorescence in situ hybridization (FISH), in combination with polymerase chain reaction and sequencing (FISHseq) was investigated. Methods and results In 36 patients with CIED infections, FISHseq of explanted devices was performed and compared with standard microbiological cultivation of preoperative and intraoperative samples. The mean age was 61.9 (±16.2) years; 25 (69.4%) were males. Most patients (62.9%) had heart failure with reduced ejection fraction. Infections occurred as endoplastits (n = 26), isolated local generator pocket infection (n = 8), or both (n = 2); CIED included cardiac resynchronization therapy defibrillator (n = 17), implantable cardioverter defibrillator (n = 11), and pacemaker (n = 8) devices. The overall positive FISHseq detection rate was 97%. Intraoperatively, pathogens were isolated in 42 vs. 53% in standard cultivation vs. FISHseq, respectively. In 16 of 17 FISHseq-negative patients, the nucleic acid strain DAPI (4′,6-diamidino-2-phenylindole) indicated inactive microorganisms, which were partially organized in biofilms (n = 4) or microcolonies (n = 2). In 13 patients in whom no pathogen was identified preoperatively, standard cultivation and FISHseq identified pathogens in 3 (23%) vs. 8 (62%), respectively. For the confirmation of preoperatively known bacteria, a combined approach was most efficient. Conclusion Fluorescence in situ hybridization sequencing is a valuable tool to detect causative microorganisms in CIED infections. The combination of FISHseq with preoperative cultivation showed the highest efficacy in detecting pathogens. Additional cultivation of intraoperative tissue samples or swabs yielded more confirmation of pathogens known from preoperative culture. [ABSTRACT FROM AUTHOR]

Keywords: left ventricular assist devices; outflow graft obstruction; pump thrombosis EN left ventricular assist devices outflow graft obstruction pump thrombosis 155 158 4 12/22/21 20220101 NES 220101 A patient was admitted in cardiogenic shock and a constant decrease of pump flow requiring combined inotropic support. Left ventricular assist devices, outflow graft obstruction, pump thrombosis. [Extracted from the article]

Aims: This EUROMACS study was conducted with the primary aim of investigating the association between a centre's annual caseload and postoperative outcomes among patients undergoing left ventricular assist device (LVAD) implantation., Methods and Results: A total of 4802 patients identified between 2011 and 2020 from 35 participating centres were dichotomized based on the annual caseload of the treating centre at the time of device implant (≤30 vs. >30 LVAD implantations/year). The primary endpoint was 1-year survival. Secondary outcomes included overall survival analysis, device-related adverse events and readmissions. Cumulative follow-up was 10 003 patient-years, with a median follow-up of 1.54 years (interquartile range 0.52-3.15). Patients from higher volume centres more frequently presented in INTERMACS levels 1 and 2, suffered from right heart dysfunction and needed inotropic support. No difference was observed in adjusted 1-year survival. Adjusted overall survival probability was lower in higher volume centres (p = 0.002). In the subgroup analysis of HeartMate 3 devices only, higher volume centres were associated with decreased odds of 1-year survival (adjusted odds ratio 0.43, 95% confidence interval 0.20-0.97, p = 0.041). Similar findings were observed in the cumulative (i.e. learning curve) caseload analyses., Conclusion: In patients undergoing LVAD implantation, centre volume was not associated with 1-year survival, but was related to device-related adverse events. Patient profiles differed with respect to centre size. These findings underscore the necessity for ongoing quality improvement initiatives in all centres, regardless of their annual caseload. Efforts are needed to standardize patient selection and preconditioning to further improve patient outcome., (© 2024 The Author(s). European Journal of Heart Failure published by John Wiley & Sons Ltd on behalf of European Society of Cardiology.)