Abstract 16045: Association between Septal Strain Rate Measured by Speckle Tracking Echocardiography and Histopathology in Hypertrophic Cardiomyopathy Patients undergoing Septal Myectomy
Background: Hypertrophic cardiomyopathy (HCM) is histopathologically (HP) characterized by myocyte hypertrophy, disarray, interstitial fibrosis and small intramural coronary arteriole dysplasia (SICAD); which contribute to its characteristic risk profile and disease progression, including diastolic dysfunction. Longitudinal systolic and early-diastolic strain rate (SR) measurements by speckle tracking echocardiography (STE) are sensitive markers of regional myocardial dysfunction (common in such patients). We sought to determine the association between septal SR and HP in symptomatic HCM patients that underwent surgical myectomy.
Methods: We studied 199 consecutive symptomatic HCM patients with basal septal hypertrophy that underwent surgical myectomy to relieve left ventricular outflow tract obstruction (LVOTO). Various echocardiographic parameters and diastolic parameters were recorded. Segmental longitudinal systolic and early-diastolic SR was measured by STE from apical 4 and 2 chamber views by tracking the mid-myocardium (VVI 2.0, Siemens, Erlangen). HP myocyte hypertrophy, disarray, SICAD and interstitial fibrosis were classified as none, mild (1–25 %), moderate (26–50 %) and severe (> 50 %).
Results: The mean age was 54 ± 12 years (50 % men, 13 % obstructive coronary artery disease or CAD), ejection fraction 62 ± 5 %, mean LVOT gradient 102 ± 39 mm Hg and basal septal thickness of 2.14 ± 0.5 cm. There was an inverse association between myocyte hypertrophy, disarray and IF (but not SICAD) seen on HP and both systolic and early diastolic septal SR (Figure). There was no association between HP and other clinical, demographic and echocardiographic parameters, including E/E′ (Figure) and deceleration time.
Conclusions: In HCM patients that underwent surgical myectomy, there is inverse association between HP and septal SR. SR measurement might potentially provide in vivo information about regional myocardial dysfunction in HCM patients.
- © 2010 by American Heart Association, Inc.