[Clinical diagnosis and pathogenesis of myocardial infarction complicated by hypertrophic cardiomyopathy: review of eight cases].
Among 144 patients with hypertrophic cardiomyopathy, eight (58.3 +/- 7.0 years, M:F = 7:1) had complicating myocardial infarction, which was diagnosed clinically and by elevated cardiac enzymes or new Q-waves on electrocardiography. Coronary occlusion or stenosis evidenced by coronary angiography and nuclear cardiological findings were investigated. In six of the eight patients, coronary atherosclerosis caused infarction. These patients had many coronary risk factors compared to the other two patients. Sixteen of the 144 patients (11%) with hypertrophic cardiomyopathy had coronary atherosclerosis, the rate of which is reportedly 10 to 20%. Two of the eight patients had no coronary atherosclerosis. One patient had a diffusely spastic diathesis provoked by the intravenous administration of ergonovine maleate during coronary angiography, suggesting that coronary spasm caused myocardial infarction. The other patient had recurrent episodes of supraventricular tachyarrhythmia and no evidence of spasm during coronary angiography, suggesting coronary embolism as a cause of myocardial infarction. Myocardial infarction in patients with hypertrophic cardiomyopathy and normal coronary arteries as advocated by Maron et al. may have such pathogenesis. We conclude that coronary angiography may be mandatory in patients with hypertrophic cardiomyopathy, especially those who have many coronary risk factors and anginal symptoms. In these patients, ST-T changes and abnormal Q-waves on electrocardiography sometimes may be misleading when diagnosing the occurrence of acute myocardial infarction by electrocardiography alone. In such cases, infarct-avid scintigraphy with 99 m-Tc pyrophosphate is preferable.
Komiyama
N
N
Cardiovascular Center, Toranomon Hospital, Tokyo.
Nishiyama
S
S
Nakanishi
S
S
Nishimura
S
S
Kato
K
K
Seki
A
A
Daida
H
H
Takaya
J
J
Yamaguchi
H
H
D000328:Adult; D000368:Aged; D002312:Cardiomyopathy, Hypertrophic / Q000150:complications*; D017023:Coronary Angiography; D003324:Coronary Artery Disease / Q000150:complications; D003329:Coronary Vasospasm / Q000150:complications; D011756:Diphosphates; D004562:Electrocardiography; D004617:Embolism / Q000150:complications; D005260:Female; D006321:Heart / Q000000981:diagnostic imaging; D006352:Heart Ventricles / Q000000981:diagnostic imaging; D006801:Humans; D008297:Male; D008875:Middle Aged; D009203:Myocardial Infarction / Q000175:diagnosis* / Q000209:etiology; D011877:Radionuclide Imaging; D013667:Technetium; D016698:Technetium Tc 99m Pyrophosphate; D013794:Thallium Radioisotopes
D011756:Diphosphates; D013794:Thallium Radioisotopes; D016698:Technetium Tc 99m Pyrophosphate; D013667:Technetium