Abnormal stress echocardiography findings in cardiac amyloidosis.

BACKGROUND

Cardiac involvement in immunoglobulin light chain (amyloid light chain, AL) amyloidosis is characterized by myocardial interstitial deposition but can also cause obstructive deposits in the coronary microvasculature.

METHODS

We retrospectively identified 20 patients who underwent stress echocardiography within 1 year prior to the histologic diagnosis of AL amyloidosis. Only patients with cardiac amyloidosis and no known obstructive coronary disease were included.

RESULTS

Stress echocardiograms (13 exercise; 7 dobutamine) were performed for evaluation of dyspnea and/or chest pain. Stress-induced wall motion abnormalities (WMAs) occurred in 11 patients (55%), 4 of whom had normal left ventricular wall thickness. Coronary angiogram was performed in 9 of 11 patients and demonstrated no or mild epicardial coronary artery disease. Seven (54%) patients had an abnormal exercise blood pressure which occurred with similar likelihood between those with and without stress-induced WMAs.

CONCLUSIONS

Stress-induced WMAs and abnormal exercise blood pressure may occur in patients with cardiac AL amyloidosis despite the absence of significant epicardial coronary artery disease. This finding should raise the possibility of cardiac amyloidosis even in the absence of significant myocardial thickening.