MRI based non-invasive detection of cardiomyocyte hypertrophy and cell-volume changes

Background Cardiomyocyte hypertrophy occurs in cardiomyopathies and in response to pressure overload. However, only endomyocardial biopsies allow detection, with the inherent risks of invasive catheter-based procedures. Noninvasive detection of cardiomyocyte hypertrophy using imaging may detect disease at a subclinical stage and potentially guide therapy. To-date, no imaging-technique has been validated to detect hypertrophic response at the cellular level. We developed a novel measure of cell size based on the MRI determination of the intra-cellular lifetime (τic) of water, using pre/post-contrast T1 measurements and a 2-site H-exchange model (2SXmodel). We hypothesized that τic correlates positively with the histological measure of cardiomyocyte volume (Vic) in a rodent model of hypertensive heart disease.