EFFECT OF ISOSORBIDE-DINITRATE ON THE ABNORMAL, EXERCISE-INDUCED 201-THALLIUM MYOCARDIAL PERFUSION SCINTIGRAPHY IN PATIENTS WITH SEVERE CORONARY-ARTERY DISEASE

  • 1 January 1979
    • journal article
    • research article
    • Vol. 68  (10) , 676-686
Abstract
The effect of isosorbide dinitrate (ISDN) (10 mg sublingually) on myocardial perfusion during ischemic conditions was analyzed in 14 patients with angiographically severe coronary artery disease and typical angina pectoris, using 201Th myocardial scintigraphy. All patients underwent 2 identical scintigrams with the same work load during bicycle ergometry; a control scintigram leading to angina and ST depressions of > 0.1 mV was followed 4-6 wk later by a scintigram after ISDN; all drugs except sublingual nitroglycerin were withheld for an entire week. Of 39 new or enlarged, exercise-induced defects, 25 (64%) were normalyzed after ISDN; 14 new or enlarged defects remained unchanged (P < 0.0005). In the 11 patients in whom ISDN led to complete abolishment of angina, 23 of 30 new defects (76%) were normalized against 0 in the 3 patients with persistent angina and ST depressions. Quantitation of perfusion was attempted by calculating the average impulse rate (counts/min per matrix point). In those patients reacting favorably by ISDN, the average impulse rate decreased significantly especially in the normal area (P < 0.001), resulting in a more homogeneous distribution of Th activity, indicating a marked reduction in local O2 consumption.