Layer-specific longitudinal strain predicts left ventricular maximum wall thickness in patients with hypertrophic cardiomyopathy

AIMS

The aim of this study was (a) to clarify the detailed mechanisms of structural and functional abnormalities of myocardial tissue in hypertrophic cardiomyopathy (HCM) using layer-specific strain (LSS) and compare it with healthy subjects (b) to investigate the diagnostic accuracy of LSS for HCM.

METHODS AND RESULTS

Forty-one patients with HCM and preserved left ventricular ejection fraction (LVEF; 66% male, 52 ± 18 years, LVEF 62.9% ± 3.7%) and 41 controls matched for age and sex (66% male, 52 ± 20 years, LVEF 63.5% ± 8.2%) underwent 2D-speckle tracking echocardiography. Absolute values of LSS were globally lower and the ratio of endocardial/epicardial layer (End/Epi ratio) was higher in HCM. LSS gradually increased from the epicardial toward the endocardial layer at all chamber views and at all levels of the LV. LSS and End/Epi ratio at the apex were higher than those at the middle or basal level of the LV. End/Epi ratio was correlated with LV maximal wall thickness both controls (r = .35, P = .03) and HCM (r = .81, P < .001). End/Epi ratio was an independent factor associated with LV maximal wall thickness (β = 0.96, P < .001). A higher End/Epi ratio (≥1.31) was associated with diagnostic criteria for HCM (sensitivity 98%, specificity 95%, area under the curve 0.99, P < .001).

CONCLUSION

LSS has the potential for unraveling the mechanism of impaired LV wall motion in HCM and to accurately detect HCM.

Myocardial multilayer strain does not provide additional value for detection of myocardial viability assessed by SPECT imaging over and beyond standard strain

BACKGROUND

The aim of this study was to evaluate the value of multilayer strain analysis to the assessment of myocardial viability (MV) through the comparison of both speckle tracking echocardiography and single-photon emission computed tomography (SPECT) imaging. We also intended to determine which segmental longitudinal strain (LS) cutoff value would be optimal to discriminate viable myocardium.

METHODS

We included 47 patients (average age: 61 ± 11 years) referred to our cardiac imaging center for MV evaluation. All patients underwent transthoracic echocardiography with measures of LS, SPECT, and coronary angiography.

RESULTS

In all, 799 segments were analyzed. We correlated myocardial tracer uptake by SPECT with sub-endocardial, sub-epicardial, and mid-segmental LS values with r = .514 P < .0001, r = .501 P < .0001, and r = .520 P < .0001, respectively. The measurements of each layer strain (sub-endocardial, sub-epicardial, and mid) had the same performance to predict MV viability as defined by SPECT with areas under curve of 0.819 [0.778-0.861, P < .0001], 0.809 [0.764-0.854, P < .0001], and 0.817 [0.773-0.860, P < .0001], respectively. The receiver-operating characteristic analysis yielded a cutoff value of -6.5% for mid-segmental LS with a sensitivity of 76% and specificity of 76% to predict segmental MV as defined by SPECT.

CONCLUSIONS

Multilayer strain analysis does not evaluate MV with more accuracy than standard segmental LS analysis.