Recently, we established a pharmacodynamic assay to monitor immunosuppressive effectiveness of cyclosporine A (CsA) in patients on standard CsA regimen. The aim of the present study was to extend this correlation to reduced CsA regimen and to compare pharmacodynamic and kinetic parameters to allow prediction of rejections and infections. In 53 heart allograft recipients, nuclear factor of activated T cells (NFAT)-regulated gene expression was quantified at trough (C0) and 2-h post-CsA dose (C2). Gene expression at C2 was calculated relative to C0 (residual gene expression, RGE) or relative to a healthy reference group (absolute gene expression, AGE). RGE correlated with CsA C2-levels in bimodal fashion: above 575 ng/ml correlation was seen with flat regression gradient. Below 575 ng/ml, correlation was excellent with markedly steeper gradient. At C0 in the low-C2 group (575 ng/ml) AGE was markedly reduced. In both groups, AGE at C2 was strongly inhibited. In patients contracting infection during follow-up, RGE was lower than in those without infections independent of CsA levels. CsA-monitoring by quantitation of NFAT-regulated gene expression is feasible with standard and reduced CsA regimens. It correlates better with the incidence of infections than measurement of CsA concentrations and might help in avoiding over-immunosuppression.

Background: Percutaneous tricuspid valve leaflet repair is an emerging treatment option for severe tricuspid regurgitation (TR). Recent studies demonstrated the usefulness and feasibility of the lately introduced TriClip and PASCAL Transcatheter Valve Repair System. However, initial experiences regarding safety and efficacy of the novel transcatheter PASCAL Ace implant system have not yet been reported. Methods: Sixteen patients with severe, massive, or torrential TR underwent tricuspid leaflet repair using the PASCAL Ace implant at our cardiology department. All patients suffered from symptomatic right-sided heart failure with New York Heart Association functional class III or IV. Clinical, laboratory, echocardiographic, and procedural data were assessed. The primary efficiency end point was postprocedural reduction in TR of at least 1 grade. Secondary end points were feasibility, safety, clinical outcome, and improvement of structural and functional right heart parameters obtained by echocardiography. Results: Eleven procedures (69%) resulted in successful reduction of TR. In 4 patients, PASCAL Ace implantation was not successful and one patient did not achieve TR reduction despite PASCAL Ace implantation. One major bleeding related to the intervention occurred. Eight patients (73%) with successful TR reduction reported a significant improvement of New York Heart Association functional class 4 weeks after implantation ( P =0.008). A significant reduction in right atrial volume from 84±41 mL/m ² to 69±36 mL/m ² ( P =0.004) and right ventricular end-diastolic diameter from 50±7 mm to 47±8 mm ( P =0.013) was observed; however, we did not see an improvement in right ventricular function directly after implantation. Conclusions: Tricuspid valve leaflet repair using the transcatheter PASCAL Ace implant system has the potential to improve clinical status and right heart reverse remodeling in patients with severe TR.

Cellular morphology has the capacity to serve as a surrogate for cellular state and functionality. However, primary cardiomyocytes, the standard model in cardiovascular research, are highly heterogeneous cells and therefore impose methodological challenges to analysis. Hence, we aimed to devise a robust methodology to deconvolute cardiomyocyte morphology on a single-cell level: C-MORE (cellular morphology recognition) is a workflow from bench to data analysis tailored for heterogeneous primary cells using our R package cmoRe. We demonstrate its utility in proof-of-principle applications such as modulation of canonical hypertrophy pathways and linkage of genotype-phenotype in human induced pluripotent stem cell-derived cardiomyocytes (hiPSC-CMs). In our pilot study, exposure of cardiomyocytes to blood plasma prior to versus after aortic valve replacement allows identification of a disease fingerprint and reflects partial reversibility following therapeutic intervention. C-MORE is a valuable tool for cardiovascular research with possible fields of application in basic research and personalized medicine.

Cardiac macrophages facilitate electrical conduction through the atrioventricular-node (AV) in mice. A possible role for cardiomyocyte-macrophage coupling on the effect of antiarrhythmic therapy has not been investigated yet. Holter monitoring was conducted in LysM^CrexCsf1r^LsL−DTR mice (MM^DTR) under baseline conditions and after an elctrophysiological stress test by flecainide. In vivo effects were recapitulated in vitro by patch-clamp experiments. The underlying mechanism was characterized by expression and localization analysis of connexin43 (Cx43) and voltage-gated-sodium-channel-5 (Na_v1.5). ECG monitoring in MM^DTR mice did not show any significant conduction abnormalities but a significantly attenuated flecainide-induced extension of RR- and PP-intervals. Patch-clamp analysis revealed that the application of flecainide to neonatal rat ventricular cardiomyocytes (CMs) changed their resting-membrane-potential (RMP) to more negative potentials and decreased action-potential-duration (APD50). Coupling of macrophages to CMs significantly enhances the effects of flecainide, with a further reduction of the RMP and APD50, mediated by an upregulation of Cx43 and Na_v1.5 surface expression. Macrophage depletion in mice does not correlate with cardiac electric conduction delay. Cardiac macrophages amplify the effects of flecainide on electrophysiological properties of cardiomyocytes in vivo and in vitro. Mechanistically, formation of macrophage-cardiomyocyte cell–cell-contacts via Cx43 facilitates the recruitment of Na_v1.5 to the cell membrane increasing flecainide effects.