Left ventricular diastolic stiffness assessed by diastolic wall strain with conventional echocardiographic study: clinical and experimental observations

ENNIS IL; BRODA D; PINILLA OA; CINGOLANI HE; ESCUDERO EM

Atenas

Congreso; Joint Meeting ESH-ISH-Hypertension; 2014

ESH-ISH

Objective The purpose of this investigation is to evaluate left ventricular diastolic wall strain (dws) based on the linear elastic theory, by echocardiography, in hypertensive patients (HT) and in spontaneously hypertensive rats (SHR). Design and method 15 consecutive HT and 15 normotensive (NT) for the same community and 24 rats, 8 normotensive (W) and 16 SHR: 8 controls and 8 treated (SHR T) with cariporide were studied. Echocardiography was performed in humans and animals to evaluate left ventricular (LV) structure and function. Dws was calculated according to Takeda et al. (J Cardiac Fail 2009;15:68-77). All the rats were sacrificed to weigh the heart, to measure the cross-sectional area of the myocytes, the fractional volume of collagen and the LV papillary muscle distensibility. Results LV mass index (LVMI) was higher (NT: 58,.89 ± 3.34 g/m2 ; HTA: 102.13± 8.6 g/m2, - p<0.01) and Dws was lower (NT: 0.46 ± 0.02, HTA: 0.38 ± 0.03- p<0.02) in HT; besides SHR also showed higher LVMI (W: 1.46±0.04 mg/g; SHR 2,31±0,15 mg/g ? p< 0,01) with bigger size of myocytes (W: 285.26±18.47 mm2, SHR: 447.38±36.94 mm2-p< 0,05), fractional volume of collagen (W: 2,50±0,30%, SHR:8,50±0,29%- p<0,05), worse papillary muscle distensibility (W: 0,013 ± 0,002 g/mm, SHR: 0,078 ± 0,0154 g/mm, p<0,05), and lowest Dws (W: 0,52± 0,01, SHR: 0,32±0,02- p<0,05). SHRT had LVMI (SHR-T: 1,59±0,14 mg/g, p<0,05), myocytes size (SHR-T: 287,32±20,52 mm2-p<0,05), and fraction volume of collagen (SHR T: 1,20±0,30%, p<0,05) reduction with improvement of papillary muscle distensibility (SHR-T: 0,010 ± 0,0021 g/mm - p<0,05) and Dws (SHR-T: 0,42±0,03% -p<0,05). Conclusions The analyzed results allow conclude that the utilization of an index of easy obtaining with transthoracic conventional echocardiogram, be effective to characterize the state of rigidity of the LV in human and animals model with arterial hypertension. This concept can be important to advance in the knowledge of the mechanisms that conduct to heart failure in this scenario.