Effects of vasodilator therapy for severe pump failure in acute myocardial infarction on short-term and late prognosis.

Abstract

Forty-three patients with severe pump failure complicating acute myocardial infarction were treated with vasodilators (nitroprusside (40) and phentolamine (3)) for four hours to 27 days. Cardiac index, stroke volume index, and stroke work index (SWI) increased while the left ventricular filling pressure (LVFP) decreased during vasodilator therapy. Twenty-four of the 43 patients (56%) survived. Of patients with initial SWI between 11-20 gm-m/m2 and LVFP less than 15 mm Hg, 68% survived. In contrast only 18% of patients with SWI of 10 gm-m/m2 or less and LVFP greater than 15 mm Hg survived. Of the 17 patients with clinical shock, 8 (47%) survived. All 24 patients discharged from the hospital were followed for at least 12 months. Fourteen patients died one to 25 months (average 9.2 months) after discharge and the cause of death was pump failure in ten of them (71%). The ten survivors at last follow-up had been followed for 15 to 32 months (average 24 months). The cumulative survival at 24 months was 28%. Thus, despite improvement in short-term prognosis with vasodilator therapy in patients with severe pump failure complicating acute myocardial infarction, the prognosis for long term survival remains unfavorable, possibly due to severe intrinsic cardiac damage.

Experimental study of afterload-reducing therapy: the effects of the reduction of systemic vascular resistance on cardiac output, aortic pressure and coronary circulation in isolated, ejecting canine hearts.

“…We conclude that (1) a substantial portion of patients with refractory congestive heart failure either do not have a beneficial response to vasodilator therapy or discontinue it because of side effects; (2) VASODILATOR drugs improve cardiac performance in patients with chronic congestive heart failure.1'~' Hydralazine, whose predominant effect is arteriolar vasodilation, has been shown to increase cardiac output in these patients.2 8 8-11 When hydralazine is combined with long-acting nitrates, left ventricular filling pressure is also reduced." 10 Although combined vasodilator therapy acutely improves hemodynamics, the long-term results of such therapy are uncertain in patients with chronic heart failure, who have a poor prognosis.12 14 We undertook this study to examine the long-term clinical effects of vasodilator therapy with hydralazine and nitrates in patients with chronic refractory congestive heart failure and to determine whether the initial clinical or hemodynamic variables are predictive of the late response.…”

“…The study population consisted of 34 consecutive patients admitted to our institution for management of congestive heart failure who met the following criteria: (1) congestive heart failure refractory to conventional medical therapy with digitalis and diuretics; (2) …”

Management of Shock in Acute Myocardial Infarction: Changing Concepts; Past, Present and Future

“…On the other hand, a study in which hemodynamic moni toring of central pressures was not done indi cated that nitroprusside lowered mortality at 7 days and 4 weeks, and reduced the inci dence of cardiogenic shock and heart failure [24]. In an earlier study, 43 patients with severe pump failure who were treated with nitroprusside during acute infarction had a lower early mortality than historical controls; however, the majority of the survivors died within 25 months [25].…”

The Heart Failure Paradox: An Epidemic of Scientific Success

“…[15][16][17][18] Using these drugs in a hypotensive patient with pulmonary edema seemed counterintuitive at first, and these clinical pioneers were often met with skepticism. 19 But their ideas worked!…”