Classification and differential diagnosis of the myocardiopathies

Cardiomyopathy: how far have we come in 25 years, how far yet to go?

Twenty-five years ago clinical investigators began to appreciate that cardiomyopathy is an important and reasonably common form of heart disease. Since then, several functional classifications have been proposed, the specific myocardial diseases have been classified and chronic ischemic ventricular failure has been described. The boundary separating myocarditis from dilated cardiomyopathy remains hazy and, despite intensive research, the causes of dilated cardiomyopathy remain obscure. In particular, we still do not understand the role that may be played by viral infection and alcohol. Myocardial biopsy has proved useful in patients with specific myocardial disorders, heart transplant recipients and patients receiving Adriamycin, but is disappointing in patients with dilated cardiomyopathy. It has become increasingly evident that exercise capacity does not correlate with ventricular function, being highly dependent on peripheral factors. Measurements of oxygen consumption during exercise promise to be useful in assessing treatment of dilated cardiomyopathy. True restrictive cardiomyopathy is uncommon, and the term should be reserved for cardiomyopathies that meet strict criteria. A restrictive component to filling is common to many cardiac disorders, including some cases of cardiac amyloidosis. The concept of hypertrophic cardiomyopathy has evolved rapidly over the past 25 years, and continues to evolve. The importance of arrhythmia as a cause of sudden death is becoming increasingly clear. The place of calcium channel blocking agents in the treatment of hypertrophic cardiomyopathy will probably emerge soon. Amiodarone is finding an increasing role in the treatment of dilated and hypertrophic cardiomyopathy. Surgical treatment is still required for some patients despite unanswered questions on how it works.

Cardiomegaly of unknown origin among Nigerian adults: role of hypertension in its aetiology

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Primary myocardial disease and alcoholism. The clinical manifestations and course of the disease in a selected population of patients observed for three or more years

The course of primary myocardial disease (PMD) was observed in 39 alcoholics. After initial examination 3 years or more before this report, we classified the severity of each patient's illness as stage I, II, or III. Stage I patients had minimal symptoms and normal-sized hearts. Stage II patients had evidence of concentric left ventricular hypertrophy and clinical manifestations like those of hypertensive heart disease. Stage III patients had left, and frequently right, ventricular hypertrophy and dilatation associated with persistent congestive heart failure, and clinical manifestations typical of patients with PMD. Only the duration of congestive heart failure differed significantly between stages II and III. Eight patients had exploratory mediastinotomy and myocardial biopsy. Gross and microscopic findings supported the diagnosis of PMD and our classification of severity and revealed diffuse interstitial fibrosis. Fifteen patients have been observed for 3 or more years; 10 have died and 14 have disappeared. These studies emphasize alcoholism's importance in the genesis of this form of PMD. Correlations were positive between abstention from alcohol and waning of clinical severity, and between persistent drinking and waxing of clinical severity.