Page 122 - Advanced echocardiography in characterization and management of patients with secondary mitral regurgitation

Chapter six. Right ventricular - pulmonary artery coupling
were identified from April 1999 to July 2017 and included in this retrospective analysis. Patients with previous mitral valve intervention and missing echocardiographic data were excluded. Clinical and demographic characteristics at baseline were collected through the departmental clinical database (EPD-Vision 11.8.4.0; Leiden University Medical Center, Leiden, The Netherlands) and included cardiovascular comorbidities, New York Heart Association (NYHA) functional class, HF etiology and medication use. The institutional review board waved the need for written patient informed consent for this retrospective study with clinically acquired data.
Echocardiography
Using commercially available systems (General Electric Vingmed Ultrasound, Milwaukee, USA) equipped with 3.5 MHz or M5S transducers, transthoracic echocardiography data were acquired in hemodynamically stable patients in the left lateral decubitus position. Parasternal, apical, and subcostal views were acquired and two-dimensional images, M-mode and Doppler data were digitally stored for offline analysis (EchoPAC 201.0.0, General Electric Vingmed Ultrasound, Norway). 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 (13). LA volume was calculated at end-systole from the apical 4- and 2-chamber views (13). LV and LA volumes were indexed for body surface area. LV global longitudinal strain (GLS) was measured from standard 2-dimensional transthoracic echocardiography using the apical 4-chamber, 2-chamber, and long-axis views of the LV (14). LV GLS was determined offline using commercially available software (EchoPAC 201.0.0, General Electric Vingmed Ultrasound, Norway). According to current recommendations, an integrative approach (including qualitative, semiquantitative, and quantitative data) was used to grade MR severity given the following definitions: moderate (grade 2), moderate to severe (grade 3), and severe (grade 4) (15, 16). The vena contracta width was measured on the parasternal long- axis view at the narrowest part of the MR jet (17). The effective regurgitant orifice area (EROA) and regurgitant volume (RVol) were measured according to the proximal isovelocity surface area (PISA) method. An EROA of ≥20mm2 and/or a RVol of ≥30 mL/ beat defined prognostically severe MR (15, 18, 19). 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 (E/e’) was calculated (20). TAPSE was measured on the apical 4-chamber view using the M-mode to evaluate RV systolic function (21). The PASP was estimated using the peak velocity of the tricuspid regurgitant jet and the Bernoulli equation and, depending on the diameter and collapsibility of the inferior vena cava, 3, 8 or 15 mmHg were added (21). In patients with atrial fibrillation the average of 3 cardiac beats were calculated. As previously suggested (12), the TAPSE/PASP ratio
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