Left-Ventricular Filling Disturbances in Cardiac Amyloidosis

Cardiac amyloidosis is characterized by left-ventricular filling defects at a relatively early stage. To investigate such defects more precisely, we studied atrial sound and left-ventricular inflow velocity patterns in 12 patients with cardiac amyloidosis (mean age 60.9 ± 12.5 years). Twelve age-matched cases with hypertrophic cardiomyopathy (HCM) served as controls. We recorded the amplitude of the atrial sound by low-frequency phonocardiography and measured the height of the A wave of apexcardiogram (ACG-A wave) as well as its ratio to the total amplitude of the ACG. Using pulsed Doppler echocardiography, we measured the rapid filling wave (E) and the atrial filling wave (A) and calculated the ratio of A to E. In the amyloidosis group, the atrial sound was weaker and the ACG-A wave was significantly smaller than in the HCM group (p < 0.001; 12.4 ± 3.9 vs. 22.4 ± 5.6%). As concerns the left-ventricular inflow velocity patterns, both the E wave (41.7 ± 16.0 vs. 56.4 ± 12.1 cm/s; p < 0.02) and the A wave (40.5 ± 13.4 vs. 58.1 ± 13.0 cm/s; p < 0.006) were smaller than in the HCM group. The A/E was 1.0 ± 0.34 in the amyloidosis group and 1.1 ± 0.3 in the HCM group (NS). We conclude that disturbed left-ventricular filling, especially in the atrial filling period, decreases the amplitude of both atrial sound and ACG-A wave in cardiac amyloidosis.