Persistent myocardial ischemia after termination of dipyridamole-induced ventricular tachycardia by intravenous aminophylline: scintigraphic demonstration.
Ventricular tachycardia is a rare complication of dipyridamole stress testing. We present a case in which dipyridamole induced symptomatic ventricular tachycardia. The patient, a 41-year-old man with a history of chest discomfort on exertion for 1 year, underwent dipyridamole thallium imaging. Sustained ventricular tachycardia occurred 1 minute and 40 seconds after completion of the dipyridamole infusion. Intravenous aminophylline (125 mg) was given immediately and the tachycardia was terminated. Two minutes later, thallium-201 was injected and subsequent myocardial imaging showed reversible perfusion defects in the inferior wall, septum, and apex. Coronary angiography revealed three-vessel disease. This case discloses that reversible perfusion defects can still be demonstrated on thallium scan in spite of injection of aminophylline, an antagonist of dipyridamole, before thallium administration.
Chang
W T
WT
Department of Internal Medicine, National Taiwan University Hospital, Taipei.
Lin
L C
LC
Yen
R F
RF
Huang
P J
PJ
D000328:Adult; D000628:Aminophylline / Q000627:therapeutic use*; D004176:Dipyridamole / Q000009:adverse effects*; D006801:Humans; D008297:Male; D017202:Myocardial Ischemia / Q000000981:diagnostic imaging*; D011877:Radionuclide Imaging; D017180:Tachycardia, Ventricular / Q000139:chemically induced* / Q000188:drug therapy; D013794:Thallium Radioisotopes
D013794:Thallium Radioisotopes; D000628:Aminophylline; D004176:Dipyridamole