ADVANTAGE OF COMBINED CAPTOPRIL-NITRATE T HERAPY FOR SEVERE CONGESTIVE-HEART-FAILURE

We compared the acute hemodynamic effects of captopril and nitrates in 11 patients with severe congestive heart failure and grade IV cardiac disability. Pressures were measured using a Swan-Ganz catheter system ; cardiac output and stroke index were measured by thermodilution, and left-ventricular (LV) volumes and ejection fraction were calculated s imultaneously with the hemodynamic measurements from radionuclide vent riculography. Measurements were made in each of 4 treatment states: co ntrol, sublingual isosorbide dinitrate (ISDN; 5 and 15 mg), oral capto pril (50-200 mg daily) and during combined therapy with captopril and ISDN. Captopril produced a fall in mean arterial pressure (p < 0.01) f rom 81 +/- 14 to 72 +/- 13 mm Hg and a rise in stroke index from 30 +/ - 5 to 35 +/- 91/min/m(2) (p < 0.05), while LV ejection fraction incre ased from 18 +/- 5 to 21 +/- 7% (p < 0.05). ISDN reduced mean arterial , pulmonary arterial, right-atrial and wedge pressure. The combination of captopril and ISDN produced a greater fall in mean arterial pressu re, a further rise in ejection fraction to 22 +/- 8% (p < 0.05), a fal l in systemic (p < 0.05) and pulmonary vascular resistance (p < 0.01) and a rise in cardiac (p < 0.01) and stroke work index (p < 0.01), whi le the beneficial effects of ISDN on right-atrial, pulmonary arterial and wedge pressure were again achieved. LV contractility, assessed fro m end-systolic stress-shortening relations, was essentially unaltered or decreased very slightly. The study showed that combined therapy wit h captopril and nitrates produced acute hemodynamic benefits superior to those achieved by treatment with captopril or nitrates alone.