Methods
Study population
We prospectively collected 25 consecutive patients who hospitalized for
multiple myeloma and diagnosed with AL-CA between April 2018 and January
2021 in the First Affiliated Hospital of Soochow University. The
diagnosis of AL-CA was established on the basis of a characteristic
echocardiogram for amyloid and a histological proof of presence of
systemic amyloid, in the absence of any other plausible causes of LV
hypertrophy10. 3 patients with AF and one with poor
imaging were excluded. As a result, 21 patients with AL-CA were enrolled
in our study. HHD group consisted with 56 randomly selected patients
with hypertensive heart disease matched with age, gender and left
ventricular mass index (LVMI). The diagnosis of hypertensive heart
disease was based on echocardiographic demonstration of a hypertrophic
LV and a history of systemic hypertension in the absence of other
cardiac or systemic disease16. Additionally, 25 age-
and gender- matched subjects with normal electrocardiography served as a
control group.
Echocardiography
The two-dimensional echocardiographic imaging of all patients was
performed by GE Vivid E95 equipment (Norway) 3.5 MHz transducer (M5S).
Patients were placed in the lateral decubitus position.
Electrocardiogram and echocardiography were recorded simultaneously.
Measurements were performed according to the guidelines of the American
Society of Echocardiography 17. Left ventricular
end-systolic diameter and left atrial anteroposterior dimension were
measured at end-systole, and left ventricular end-diastolic diameter was
measured at end-diastole on parasternal views. End-diastolic septal
thickness and posterior wall thickness were assessed on both parasternal
views and short axis views. Left ventricular ejection fraction (LVEF)
and left atrial ejection fraction were obtained by the biplane Simpson’s
method on apical 4-chamber and 2-chamber views. Pulse-wave doppler (PW)
was used to measure the peak early diastolic flow velocity (E peak),
peak late diastolic flow velocity (A peak) and E/A ratio of mitral
valve. PW was also used to measure the e’ of septal and lateral wall and
E/e’ in tissue doppler imaging (TDI) mode. Tricuspid regurgitation
velocity (TR velocity) was measured by continuous doppler (CW) under the
guidance of color doppler on apical 4-chamber views.
LA longitudinal strain analysis
Analysis of two-dimensional speckle tracking echocardiograms was
performed using Echo PAC workstation (GE, USA). The images of apical
4-chamber and 2-chamber, which could clearly show the left atrium, were
used to analyze left atrial strain by Q-Analysis method. Region of
interest (ROI) should include all left atrial myocardium but without
pericardium, so the ROI width is usually ≤3mm. Once the region of ROI
was established, the analyzer modified the region to ensure the quality
of speckle tracking (See Figure1). SD-TPS was used to measure the degree
of LA dispersion. It was calculated as the SD of time to peak and
expressed as a percentage of the R-R interval18.