Coronary and myocardial metabolic effects of combined glyceryl trinitrate and propranolol administration. Observations in patients with and without coronary disease.

Abstract

SUMMARY Coronary haemodynamic and metabolic effects of propranolol and glyceryl trinitrate were studied in 12 patients with coronary artery disease and 5 without coronary heart disease, at rest and during tachycardia stress. Propranolol-associated reductions in indices of myocardial oxygen demand, left ventricle work, tension time, and left ventricle oxygen utilisation (LVV02) were reversed when heart rate was controlled by atrial pacing. Adding glyceryl trinitrate at rest also restored heart rate but decreased the left ventricular work index and tension time index as coronary resistance declined paradoxically. Tachycardia-related increases in tension time index and LVV02 were unchanged after propranolol, and ischaemia (angina, ST depression, and reduced lactate extraction) was not altered in most of the patients. During tachycardia, the addition of glyceryl trinitrate decreased the tension time index and LVV02; angina recurred in only 4 patients, and ST depression and lactate extraction improved. Similar haemodynamic changes occurred in the patients with normal coronary arteries.In contrast with propranolol administered alone, propranolol plus glyceryl trinitrate enhances tachycardia tolerance and prevents tachycardia-induced manifestations of ischaemia. This action is attributed to glyceryl trinitrate-associated improvement in the adequacy of myocardial perfusion.Although nitrates are frequently used in combination with propranolol and have been justified by clinical and haemodynamic rationale (Russek, 1968;Wiener et al., 1969;Aronow, 1972), there is no information on the effect of this combination on the coronary circulation. Propranolol is known to reduce stress-related augmentation of cardiac rate, con-

In vivo validation of a thermodilution method to determine regional left ventricular blood flow in patients with coronary disease.

“…Thus, the technique has been useful in evaluating the effect of agents on the changes in coronary flow that occur with interventions like tachycardia stress. [3][4][5] Although adequate mixing of blood with the indicator is a fundamental assumption, accuracy of the method as an index of total left ventricular flow has been demonstrated in vitro and also in an animal model.6 7 Ganz and co-workers2 also applied an additional thermistor to the coronary sinus thermodilution technique and measured great cardiac vein flow (GCVF). The ability of the method to simultaneously measure two different blood flows was confirmed in animals.2 However, in vivo validation by an independent method in patients with coronary disease has not been described.…”

Nitroglycerin-induced Heterogeneous Subendocardial Myocardial Blood Flow Observed by Cardioscopy in Patients With Coronary Artery Disease

“…25) All of these are directly or indirectly influenced by NTG. [26][27][28][29][30][31] In the present study, NTG-induced changes in SMBF were dependent on control endocardial color, which was demonstrated by 201 Tl-scintigraphy and histology to represent severity of myocardial ischemia and fibrosis, regional wall motion, and severity of stenosis of the irrigating artery.…”

Anti‐anginal Efficacy of a Controlled‐Release Formulation of lsosorbide‐5‐mononitrate Once Daily in Angina Patients on Chronic β‐Blockade

“…The benefits of combining nitrates and @-adrenergic-blocking drugs have been documented in single-dose studies (8)(9)(10)(11)(12), in patients on chronic @-blockade to whom single-dose nitrate was added (13) and in patients on chronic nitrate therapy to whom a single-dose of the @blocker was given (14).…”