Author + information
- Tais De Jesus,
- Mahmoud Alashry,
- Sorin Pislaru,
- Ratnasari Padang,
- Elise Oehler,
- Vuyisile Nkomo,
- Patricia Pellikka and
- Cristina Pislaru
Background: Chronic left ventricular (LV) volume overload in organic mitral regurgitation (MR) triggers altered contractile proteins and collagen synthesis leading to LV remodeling and ultimately LV dysfunction. Invasive studies demonstrated increased LV compliance but conflicting findings on myocardial stiffness. We tested the hypothesis that intrinsic velocity propagation of myocardial stretch (iVP), a validated measure of myocardial elasticity, may be abnormal in these patients.
Methods: Prospective study in patients with severe (n=43) and moderate (n=8) MR, age 51±14 yrs, 73% male, in sinus rhythm (LV ejection fraction EF 63±5%, LV end-diastolic/end-systolic diameters LVEDD/LVESD 53±6/34±5 mm; NYHA I 73%, II 25%). Control group (n=46, age 50±13 yrs): patients with normal cardiac function and ≤mild valvular disease. After comprehensive TTE, high frame rate (250-350Hz) tissue Doppler scans were acquired from each LV wall (apical views); iVP was measured as the wave speed of wall stretch propagating base to apex (late diastole). Elastic modulus (EM) was derived from iVP and LV geometry. Longitudinal strain (GLS) was measured by speckle tracking.
Results: EM and iVP were highest in severe MR (EM: 27±22, 18±9 and 17±6 kPa, p=0.01, severe MR, moderate MR and controls, respectively; iVP: 1.9±0.6, 1.7±0.4 and 1.7±0.3 m/s, p=0.05). iVP correlated with severity of MR (regurgitant volume r=0.42; ERO r=0.52) and LV dimensions (LVEDD r=0.38; LVESD r=0.30; LV mass index r=0.26) (p<0.05 for all), but not with mitral A velocity, LV systolic function (EF, GLS), end-diastolic wall stress or left heart filling (E/e', Ar-A duration). In severe MR, EM was higher in patients with EF<60% (p=0.04) or LVESD>40mm (p<0.01). At multivariate analysis, EM remained associated with EF<60% (p=0.02) after accounting for age, gender and relevant imaging and clinical variables.
Conclusions: Novel noninvasive indices of myocardial elasticity indicate that patients with organic severe MR have stiffer LV myocardium. This could reflect the overload burden on LV tissue and may have potential to detect the maladaptation of the tissue before functional deterioration. Future work will test the relation with clinical outcomes.
Poster Hall, Hall C
Saturday, March 18, 2017, 3:45 p.m.-4:30 p.m.
Session Title: New Technologies in Echocardiography
Abstract Category: 28. Non Invasive Imaging: Echo
Presentation Number: 1245-213
- 2017 American College of Cardiology Foundation