Plasma Renin Activity Levels in Two Patients with Impending Cardiogenic Shock

To the Editor: Dzau and his co-workers reported in 1980 that converting-enzyme inhibitors, which block the conversion of angio-tensin I to angiotensin II, were effective in the long-term treatment of severe congestive heart failure. 1 Other groups have reported similar findings. 2 3 4 5 6 7 Because these drugs may be specifically useful in decreasing systemic vascular resistance (afterload), it is pertinent to determine the levels of plasma renin activity (PRA) in cardiogenic shock. We wish to report daily PRA levels measured in two patients who were supported with intra-aortic balloon pumping because of hemodynamic instability and impending cardiogenic shock after myocardial infarction. The first patient . . .