Regional contractility measurement of the left ventricle using gated myocardial SPECT

Maximal elastance (E_max: maximal ratio of pressure over volume) of left ventricular myocardium obtained from time-varying elastance curves represents myocardial contractility, which is independent of preload and afterload. A non-invasive method of quantifying myocardial global contractility using a single systolic PV loop was developed by Senzaki et al. and extended by Lee et al. by measuring time-volume curve using gated myocardial SPECT. Since these previous methods provide only the overall contractile function of left ventricle, we developed a method to quantify the regional contractility of myocardium. For total 55-72 regions, regional volume curve was estimated. Regional volume curves were obtained by extracting endocardial surface of left ventricle from each gated frame.