Improved myocardial contractility assessment with tagged cine MRI in cardiomyopathic patients

The purpose of this study was to assess the regional myocardial contractility with the use of cine magnetic resonance imaging (MRI) tagging in patients with hypertrophic (HCM) and dilated (DCM) cardiomyopathies. Twenty patients and 6 control subjects underwent tagged cine MRI on a 1.0 Tesla magnet. Two tagging 1:3:3:1 binomial radio-frequency pulses were applied at end-diastole to obtain the superposition of an orthogonal grid pattern and nine consecutive images were acquired. Imaging was performed in long-axis and short-axis views. An in-house image analysis program was used. Regional contractility was expressed as the % segmental shortening (%SSh) which is % change in intergrid distance from diastole to systole. Left ventricle was divided into segments for analysis. %SSh and radial displacement were calculated for each segment. Diseased myocardial segments had reduced %SSh, a more reliable parameter than the radial displacement