The clinical usefulness of the amyl nitrite inhalation test in the assessment of the third and atrial heart sounds in ischemic heart disease

Abstract

1. 1. Twenty patients with ischemic heart disease (Group A), 32 with diastolic hypertension (Group B), and 54 normal subjects (Group C) were studied in order to observe the effects of amyl nitrite inhalation on the third and atrial heart sounds. 2. 2. Fifty-five per cent of Group A, 9 per cent of Group B, and 4 per cent of Group C had a significant amplitude increase of these sounds following inhalation of amyl nitrite. 3. 3. It is possible that an increased flow load to the impaired myocardium secondary to a rise in cardiac output and venous return after amyl nitrite inhalation is sufficient to account for the augmentation of the diastolic heart sounds in the majority of the patients in Group A. 4. 4. An initial sudden drop in blood pressure and increase in heart rate may also be responsible for intensification of the diastolic sounds resulting from further coronary insufficiency in the patients with ischemic heart disease. 5. 5. The amyl nitrite inhalation test, with special reference to the diastolic heart sounds, is considered to be a simple and useful clinical procedure for evaluation of myocardial reserve function.