Assessment of atrial function by myocardial deformation techniques in hypertrophic cardiomyopathy.

BACKGROUND: Diastolic dysfunction in hypertrophic cardiomyopathy (HCM) is common, but its assessment is difficult using conventional echocardiography. AIMS: To assess left atrial (LA) function in HCM by longitudinal strain and determine its role in understanding of symptoms. METHODS: We studied 144 patients divided into 3 age- and sex-matched groups: 48 consecutive patients with HCM, 48 control subjects, and 48 athlete subjects. We assessed LA function by conventional echocardiographic parameters and by longitudinal atrial strain (early-diastolic left atrial strain during reservoir phase [LASr]; end-diastolic left atrial strain during conduit phase; end-systolic peak of the left atrial strain during contraction phase). RESULTS: NYHA classification was as follows in HCM group: I in 46%, II in 31%, III in 19%, and IV in 4%. Conventional echocardiographic parameters of diastolic function were depressed in the HCM group as compared to the control and athlete groups, but not related to symptoms. All longitudinal atrial strain parameters were significantly reduced in HCM group as compared to two groups (P < .0001). LASr was significantly correlated to peak VO2 (r = 0.44, P = .01) and was the best parameter for detecting symptomatic patients presenting with HCM, with a cutoff value of 15%: Sensitivity was 71%, specificity was 79%, PPV was 77%, and NPV was 73%. CONCLUSION: Assessment of LA function in HCM is feasible using longitudinal strain, and this technique is more reliable than conventional echocardiographic parameters for the understanding of determinants of symptoms.

Usefulness of Longitudinal Strain Adjusted to Regional Thickness in Hypertrophic Cardiomyopathy.

Background. We assessed the usefulness of a longitudinal strain adjusted to regional thickness in hypertrophic cardiomyopathy (HCM). Indeed, with conventional software, the width of the region of interest (ROI) is the same over the entire myocardial wall, wherein the software analyzes only partially the left ventricular (LV) hypertrophic segments. Methods. We included 110 patients: 55 patients with HCM (HCM group) and 55 healthy subjects (age- and sex-matched control group). The global longitudinal strain (GLS) and regional strain for each of the 17 segments was calculated with standard software (for two groups) and with software adjusted to the myocardial wall thickness (for the HCM group). Results. GLS was significantly decreased in the HCM group compared to the control group (−15.1 ± 4.8% versus −20.5 ± 4.3%, p < 0.0001). In the HCM group, GLS (standard method versus adjusted to thickness) measurements were not significantly different (p = 0.34). Interestingly, the regional strain adjusted to thickness was significantly lower than the standard strain in the hypertrophic segments, especially in the basal inferoseptal segment (p = 0.0002), median inferoseptal segment (p < 0.001) and median anteroseptal segment (p = 0.02). The strain adjusted to thickness was still significantly lower in the most hypertrophic segments (≥20 mm) (−3.7 ± 3%, versus −5.9 ± 4.4%, p = 0.049 in the basal inferoseptal segment and −5.7 ± 3.5% versus −8.3 ± 4.5%, p = 0.0007 in the median inferoseptal segment). In the segments with significant myocardial fibrosis, the longitudinal strain adjusted to thickness was significantly lower than the conventional strain (−8.3 ± 3.3% versus −11.4 ± 4.5%, p = 0.002). The analysis of the strain adjusted to thickness had a better feasibility (97.5% versus 99%, p = 0.01). Conclusions. The analysis of a longitudinal strain adjusted to regional thickness is feasible in HCM and allows a better evaluation of myocardial deformation, especially in the most LV hypertrophic segments.