Page 52 - Advanced echocardiography in characterization and management of patients with secondary mitral regurgitation

Chapter three. Prognostic Value of Left Ventricular Global Longitudinal Strain
echocardiographic database. The first echocardiogram performed with the patient in hemodynamic stable conditions and showing moderate and severe secondary MR defined the time point of entry in the analysis. Patients with previous invasive mitral valve intervention and patients with echocardiographic data not analyzable with 2D speckle-tracking echocardiography were excluded (Online Figure 1). The Institutional Review Board approved this retrospective analysis of clinically acquired data and waived the need of written patient informed consent.
Clinical variables included the New York Heart Association (NYHA) functional class, etiology of heart failure, heart rhythm, comorbidities, and medications. Ischemic etiology was defined by the presence of coronary artery disease diagnosed on invasive coronary angiography or a history of coronary revascularization with percutaneous coronary intervention or coronary artery bypass grafting (CABG). Mitral valve intervention included surgical therapy (i.e., surgical mitral valve repair, mitral valve replacement) and percutaneous edge-to-edge mitral valve repair.
Echocardiography
Transthoracic echocardiography was performed with patients at rest in the left lateral decubitus position, using a commercially available system (GE Vingmed Ultrasound, General Electric, Milwaukee, Wisconsin). Parasternal, apical, and subcostal views were acquired using 3.5 MHz or M5S transducers. Two-dimensional, M-mode, and Doppler data were stored for offline analysis (EchoPAC 201.0.0, GE Vingmed Ultrasound). LV volumes (end-systolic and end-diastolic) were measured in the apical 2- and 4-chamber views and LVEF was calculated according to Simpson’s biplane method and indexed for body surface area (6). MR severity was graded according to current recommendations using an integrative approach that includes qualitative, semiquantitative, and quantitative data: mild (grade 1), moderate (grade 2), moderate to severe (grade 3), and severe (grade 4) (7, 8, 9). Significant MR was defined by a grade of ≥2+. Parameters for LV diastolic function included peak early diastolic wave and late diastolic wave measured on pulsed wave Doppler of mitral inflow, and the peak early diastolic wave- to-late diastolic wave ratio was calculated. Using tissue Doppler imaging, the septal and lateral peak early diastolic mitral annular velocities were measured in the apical 4-chamber view (10). As a measure of LV filling pressures, the ratio between peak early diastolic transmitral flow velocity and peak early diastolic mitral annular tissue velocity ratio was calculated. The tricuspid regurgitation was assessed on continuous- wave Doppler and tricuspid regurgitation velocity was calculated. To evaluate right ventricular function, tricuspid annular plane systolic excursion was measured on the apical 4-chamber view using the M-mode (11). LV GLS was measured from standard
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