Ischemic cardiomyopathy: lack of clinical applicability of the WHO/ISFC classification of cardiomyopathies.

BACKGROUND

The classification of cardiomyopathies proposed by the WHO/ISFC Task Force defines ischemic cardiomyopathy as "a dilated cardiomyopathy with impaired contractile performance not explained by the extent of coronary disease or ischemic damage". The aim of this study was to verify the clinical applicability of the WHO/ISFC definition of ischemic cardiomyopathy.

METHODS

Retrospective analysis of the clinical characteristics of patients with a left ventricular ejection fraction < 40%, in whom coronary angiography showed a) stenosis < or = 50% of a main coronary artery and/or b) stenosis > 50% of a distal portion of a main coronary artery or of a secondary branch. The patients with a clinical diagnosis of previous myocardial infarction were excluded.

RESULTS

Fourteen patients with the angiographic characteristics listed above were identified. Twelve patients were males, mean age 59 years. They represented 3.8% of all the patients with left systolic ventricular dysfunction who underwent coronary angiography in the same period. The left ventricular end-diastolic volume was 170 +/- 45 ml/m2 and the ejection fraction was 27 +/- 6%. The cause of systolic left ventricular dysfunction was systemic arterial hypertension in 3 patients, diabetes mellitus in 2, a combination of these diseases in 4, chronic alcohol abuse in 1, a previous clinically silent myocardial infarction in 1, and idiopathic dilated cardiomyopathy in 3.

CONCLUSIONS

In conclusion, in all our patients with severe left ventricular dysfunction which was not explained by the extent of coronary artery disease, at least one possible cause of impaired contractile performance could be identified. Thus the definition of ischemic cardiomyopathy according to the new WHO/ISFC classification of cardiomyopathies appears to be of scarce utility on clinical grounds and should be redefined and if necessary reclassified.