
This study investigated the right ventricular (RV) myocyte contractile dysfunction in patients with heart failure with reduced ejection fraction and pulmonary hypertension (HFrEF-PH). Permeabilized RV cardiomyocytes were studied in patients undergoing cardiac transplantation and organ donor controls. Unsupervised machine learning identified two HFrEF-PH subgroups corresponding to decompensated or compensated clinical RV function. Reduced calcium-activated tension was observed in decompensated RV function, while other contractile measures were similarly depressed in both groups. X-ray diffraction revealed thick filament defects in decompensated RV function. Altering the proportion of myosin in a crossbridge-ready state affected tension differently in patient groups. Increasing myocyte preload had a reduced effect on myocyte stiffness in HFrEF-PH. Therapeutic strategies targeting these findings may improve outcomes in HFrEF-PH patients.
Like
Save
Share