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Background: Myocardial strain provides a novel means of quantifying subtle alterations in contractile function; incremental utility post-MI is unknown., Objectives: To test longitudinal-quantified by postprocessing routine echo-for assessment of MI size measured by cardiac magnetic resonance (CMR) and conventional methods, and assess regional and global strain (GLS) as markers of LV thrombus., Methods: The population comprised of patients with anterior ST-segment MI who underwent echo and CMR prospectively. Preexisting echoes were retrieved, re-analyzed for strain, and compared to conventional MI markers as well as CMR-evidenced MI, function, and thrombus., Results: Seventy-four patients underwent echo and CMR 4 ± 1 weeks post-MI; 72% had abnormal GLS. CMR-quantified MI size was 2.5-fold larger and EF lower among patients with abnormal GLS, paralleling 2.6-3.1 fold differences in Q-wave size and CPK (all P ≤ .002). GLS correlated with CMR-quantified MI (r = .66), CPK (r = .52) and Q-wave area (r = .44; all P ≤ .001): Regional strain was lower in the base, mid, and apical LV among patients with CMR-defined transmural MI in each territory (P < .05) and correlated with cine-CMR regional EF (r = .53-.71; P < .001) and echo wall motion (r = .45-.71; P < .001). GLS and apical strain were ~2-fold lower among patients with LV thrombus (P ≤ .002): Apical strain yielded higher diagnostic performance for thrombus (AUC: 0.83 [0.72-0.93], P = .001) than wall motion (0.73 [0.58-0.88], P = .02), as did global strain (0.78 [0.65-0.90], P = .005) compared to LVEF (0.58 [0.45-0.72], P = .41)., Conclusions: Echo-quantified longitudinal strain provides a marker of MI size and improves stratification for post-MI LV thrombus beyond conventional indices., (© 2017, Wiley Periodicals, Inc.)

Background: Ischemic mitral regurgitation (iMR) predisposes to right ventricular (RV) pressure and volume overload, providing a nidus for RV dysfunction (RVDYS) and non-ischemic fibrosis (NIF). Echocardiography (echo) is widely used to assess iMR, but performance of different indices as markers of RVDYS and NIF is unknown. Methods: iMR patients prospectively underwent echo and cardiac magnetic resonance (CMR) within 72 hours. Echo quantified iMR, assessed conventional RV indices (TAPSE, RV-S’, fractional area change [FAC]), and strain via speckle tracking in apical 4-chamber (global longitudinal strain [RV-GLS]) and parasternal long axis orientation (transverse strain). CMR volumetrically quantified RVEF, and assessed ischemic pattern myocardial infarction (MI) and septal NIF. Results: 73 iMR patients were studied; 36% had RVDYS (EF<50%) on CMR among whom LVEF was lower, PA systolic pressure higher, and MI size larger (all p<0.05). CMR RVEF was paralleled by echo results; correlations were highest for RV-GLS (r = 0.73) and lowest for RV-S’ (r = 0.43; all p<0.001). RVDYS patients more often had CMR-evidenced NIF (54% vs. 7%; p<0.001). Whereas all RV indices were lower among NIF-affected patients (all p≤0.006), percent change was largest for transverse strain (48.3%). CMR RVEF was independently associated with RV-GLS (partial r = 0.57, p<0.001) and transverse strain (r = 0.38, p = 0.002) (R = 0.78, p<0.001). Overall diagnostic performance of RV-GLS and transverse strain were similar (AUC = 0.93[0.87–0.99]|0.91[0.84–0.99], both p<0.001), and yielded near equivalent sensitivity and specificity (85%|83% and 80%|79% respectively). Conclusion: Compared to conventional echo indices, RV strain parameters yield stronger correlation with CMR-defined RVEF and potentially constitute better markers of CMR-evidenced NIF in iMR. [ABSTRACT FROM AUTHOR]