Assessment of atrial diastolic function in patients with hypertrophic cardiomyopathy by cine magnetic resonance imaging

Purpose This study was conducted to assess the role
of atrial function by cardiac magnetic resonance (CMR)
for the evaluation of diastolic physiology in patients with
hypertrophic cardiomyopathy (HCM) compared to healthy
controls.
Materials and methods We enrolled 23 consecutive
patients affected by HCM and 43 healthy subjects as agematched
control cases (CC). CMR was performed through
acquisition of cine steady-state free precession sequences
using a 1.5-T scanner. Image postprocessing was carried
out using Tracking Tool software.
Results Atrial volumes were significantly higher in
patients with HCM compared to CC: maximum atrial volume
(p = 0.007) and minimum atrial volume (p = 0.01).
A statistically significant difference was also observed in
atrial ejection fraction in patients with HCM (p < 0.0001).
The atrial volume curves defined as cavity volume over time (dV/t) showed significant differences: early atrial peak emptying
rate (PERE) (maximum rate of emptying independent
of atrial contraction) in HCM was −146 ± 53 ml/s versus
−227 ± 86 ml/s in CC (p < 0.0001); active atrial peak emptying
rate (PERA) (maximum rate of emptying secondary
to atrial contraction) in HCM was −256 ± 80 ml/s versus
−216 ± 104 ml/s in CC (p = 0.05); the atrial PER E/A ratio
in HCM was 0.6 ± 0.2 versus 1.05 ± 0.5 in CC (p < 0.0001).
Conclusions This study demonstrated that in HCM
patients with early diastolic dysfunction the parameters of
left atrial function assessed by CMR are impaired before
the ventricular diastolic indexes such as the early peak filling
rate and the active peak filling rate.