In patients undergoing elective CABG we found that (a) Con43 + TnT and Con43 + Cav3 EV concentrations were elevated in coronary sinus compared to radial artery, (b) the Con43 + TnT and Con43 + Cav3 EV profile was different in patients with HFrEF compared to those with HFpEF, (c) the coronary sinus concentrations of Con43 + TnT and Con43 + Cav3 EVs correlated significantly with echocardiographic and laboratory markers of HF. The gene discussed is CAV3; the disease is hydrops fetalis.