Serial echocardiographic observations in patients with primary systemic amyloidosis: an introduction to the concept of early (asymptomatic) amyloid infiltration of the heart.

Echocardiography was used for the serial assessment of 27 patients with primary systemic amyloidosis. Thirteen patients had no clinical cardiac deterioration between the two echocardiographic studies (group 1), whereas in 14 patients (group 2), congestive heart failure or arrhythmias (or both) appeared or worsened during a mean observation period of 19 months. The only echocardiographic changes in group 1 were a mild increase in left ventricular mass and a mild decrease in left ventricular wall systolic thickening. Patients in group 2 had significant changes in left ventricular wall thickness (mean increase, 34%), in left ventricular mass (mean increase, 42%), in right ventricular wall thickness (mean increase, 78%), in left atrial size (mean increase, 19%), in left ventricular mass/voltage ratio (mean increase, 68%), in left ventricular radius/thickness ratio (mean decrease, 29%), and in left ventricular fractional shortening (mean decrease, 13%). Significant correlations were found in group 2 between changes in systolic and diastolic blood pressure and changes in ventricular wall thickness and mass. Changes in left ventricular systolic function did not correlate significantly with changes in other clinical, electrocardiographic, or echocardiographic measurements. In six cases (two in group 1), in which amyloid infiltration of the heart was proved by myocardial biopsy or autopsy, the only echocardiographic abnormality when the patients were asymptomatic was a moderate increase in left or right ventricular wall thickness. We found that M-mode and two-dimensional echocardiographic examinations can substantiate progressive amyloid infiltration of the heart and are useful tools for the noninvasive serial assessment of patients with primary systemic amyloidosis.