Cardiovascular magnetic resonance myocardial feature tracking detects quantitative wall motion during dobutamine stress

Background: dobutamine stress cardiovascular magnetic resonance (ds-cmr) is an established tool to assess hibernating myocardium and ischemia. analysis is typically based on visual assessment with considerable operator dependency. cmr myocardial feature tracking (cmr-ft) is a recently introduced technique for tissue voxel motion tracking on standard steady-state free precession (ssfp) images to derive circumferential and radial myocardial mechanics. we sought to determine the feasibility and reproducibility of cmr-ft for quantitative wall motion assessment during intermediate dose ds-cmr. methods. 10 healthy subjects were studied at 1.5 tesla. myocardial strain parameters were derived from ssfp cine images using dedicated cmr-ft software (diogenes mri prototype; tomtec; germany). right ventricular (rv) and left ventricular (lv) longitudinal strain (ell rvand ell lv) and lv long-axis radial strain (err lax) were derived from a 4-chamber view at rest. lv short-axis circumferential strain (ecc sax) and err sax; lv ejection fraction (ef) and volumes were analyzed at rest and during dobutamine stress (10 and 20 g kg -1 min -1). results: in all volunteers strain parameters could be derived from the ssfp images at rest and stress. ecc saxvalues showed significantly increased contraction with dsmr (rest: -24.1 6.7; 10 g: -32.7 11.4; 20 g: -39.2 15.2; p < 0.05). err saxincreased significantly with dobutamine (rest: 19.6 14.6; 10 g: 31.8 20.9; 20 g: 42.4 25.5; p < 0.05). in parallel with these changes; ef increased significantly with dobutamine (rest: 56.9 4.4%; 10 g: 70.7 8.1; 20 g: 76.8 4.6; p < 0.05). observer variability was best for lv circumferential strain (ecc sax) and worst for rv longitudinal strain (ell rv) as determined by 95% confidence intervals of the difference. conclusions: cmr-ft reliably detects quantitative wall motion and strain derived from ssfp cine imaging that corresponds to inotropic stimulation. the current implementation may need improvement to reduce observer-induced variance. within a given cmr lab; this novel technique holds promise of easy and fast quantification of wall mechanics and strain. © 2011 schuster et al; licensee biomed central ltd.