PDE5A and hydrops fetalis: Given the negative impact of acute PDE5 inhibition on the inotropic and lusitropic response to catecholamines and the established loss of catecholamine reserve in HF it is somewhat surprising that an emerging body of evidence suggests PDE5 inhibition is clinically cardioprotective in type II diabetes19, left ventricular hypertrophy20 and in patients with HF with reduced ejection fraction (systolic HF)21.