Hemodynamic time course of acute and chronic isosorbide dinitrate treatment at rest and during exercise in patients with stable ischemic heart disease.
The study was undertaken to establish differences between venous and arterial isosorbide dinitrate (ISDN) effects during acute and chronic treatment, hemodynamics at rest, and during supine exercise. These effects were assessed invasively in 16 patients with stable ischemic heart disease before and at hourly intervals for 4 h after administration of peroral 30 mg ISDN. Eight patients were previously untreated (acute group), and eight were treated with 30 mg ISDN asymmetrically b.i.d. for two weeks (chronic group). Prior to ISDN administration, right atrial, mean pulmonary artery, pulmonary artery wedge, and mean arterial pressure (RAP, MPAP, PAWP, and MAP) rose from normal resting to pathologic values during exercise. One h after ISDN administration, all exercise pressures were normalized (p < 0.001). During the following 3 h, exercise RAP rose similarly in both groups (p < 0.01), while MPAP rose particularly in the chronic group (p < 0.001). Exercise PAWP and MAP, however, remained low in the acute group, but increased markedly in the chronic group (p < 0.01), particularly from the third to the fourth hour after ISDN. The daily, asymmetric administration of 30 mg ISDN b.i.d. maintained beneficial, anti-ischemic effects for 2 to 3 h after a morning dose of the drug, but thereafter attenuation of the effects occurred in the arteries but not in the veins.