Predicting the clinical course in hypertrophic cardiomyopathy using thallium‐201 myocardial scintigraphy

Abstract Aims This study aimed to evaluate the changes in left ventricular remodelling with time in patients with hypertrophic cardiomyopathy (HCM) using thallium‐201 myocardial scintigraphy. Methods and results Forty‐eight patients with HCM participated in the study. The extent score (ES) and a newly devised index termed the ‘mean count change’ (MCC) were used to evaluate the myocardial perfusion defects. Using the amount of thallium‐201 uptake (TU), MCC (%) was calculated using the following formula: (last TU − initial TU)∕initial TU × 100. To confirm the site of the lesion, the left ventricle was divided into five segments: anterior, septal, inferior, lateral, and apex. Cardiovascular complications and deaths were recorded. The mean follow‐up period was 8.6 ± 2.0 years. ES increased from 17.4 ± 13.7% to 44.0 ± 22.3% (P