Natural history of saccular aneurysms of the left ventricle.

We have studied the natural history of left ventricular aneurysms (LVA) in 40 patients not treated surgically who were followed for a mean period of 5 years, 8 months. These patients have been divided into two groups according to the presence (Group B) or absence (Group A) of significant symptomatology. The causes of death are dominated by arrhythmias and congestive heart failure (CHF). The survival rate at 10 years is 66.7% for the entire group. In asymptomatic patients the 10 year survival rate is 90%, but it is only 46.3% in those who were symptomatic at the time of the initial diagnosis. In general, the clinical course of survivors is stable in Group A but has deteriorated steadily in Group B. Nonfatal complications include arrhythmias (observed in 34% of all patients), thromboembolic phenomena (29%), CHF (29%), and recurrent myocardial infarction (22.5%). Factors influencing prognosis are the extent of the aneurysm, the association of asynergic segments, the ejection fraction of the residual ventricle, the left ventricular end-diastolic pressure (LVEDP), and the presence of ventricular extrasystoles at the time of diagnosis. The mere presence of aneurysm is not, in itself, an indication for operation. Incapacitating angina and refractory CHF are the most valuable indications for surgical resection. The question is raised as to the value of operation in patients with little or no symptoms, in those with isolated life-threatening arrhythmias, and in those in whom a mural thrombus is the only distressing feature.