Asynchronous filling in ischemic heart disease and hypertrophic cardiomyopathy

A multigated blood-pool study was performed to assess regional and global emptying and filling in 16 patients with hypertrophic cardiomyopathy (HCM), 43 patients with ischemic heart disease (IHD), and 14 controls. The regional volume curve was fitted using second-order harmonics in the Fourier series, while the global left-ventricular volume curve was fitted using third-order harmonics. As asynchronous indices, the standard deviations (SD) in distribution histograms of time to end-systole (TES), time to peak ejection (TPE), and time to peak filling (TPF) were obtained in the left ventricle. In patients with IHD, the TPF-SD was higher (14.4±11.3°) than the TES-SD (7.8±5.1°) and TPE-SD (8.1±5.9°), suggesting the presence of asynchronous filling. In patients with HCM, the TPF-SD was also higher (11.6±11.1°) than the TES-SD (3.5±2.4°) and TPE-SD (6.2±4.4°). The phase delay was localized in the anteroseptal or apical region in all 5 HCM patients with abnormal wall motion, while it corresponded with the region of abnormal wall motion in the patients with IHD. The TPF-SD was inversely correlated with the left-ventricular ejection fraction (r=-0.46), peak filling rate (r=-0.50), and the ratio of peak filling rate to peak ejection rate (r=-0.52), suggesting that asynchronous filling is related to global diastolic disturbance. We conclude that asynchronous filling is often present in patients with IHD and HCM, and that our technique can be used to obtain a quantitative assessment of regional asynchronous emptying and filling in these diseases.