Page 70 - Advanced echocardiography in characterization and management of patients with secondary mitral regurgitation

Chapter four. Regurgitant Volume/Left Ventricular End-Diastolic Volume Ratio
waived the need for written patient informed consent.
Clinical characteristics included New York Heart Association (NYHA) functional class, HF etiology, and medication use. Ischemic HF was defined based on previous coronary revascularization with percutaneous coronary intervention or coronary artery bypass grafting and/or coronary artery disease diagnosed on invasive coronary angiography.
Echocardiography
Transthoracicechocardiographywasperformedwithpatientsinhemodynamicallystable condition at rest in the left lateral decubitus position, using a commercially available system (General Electric Vingmed Ultrasound, Milwaukee, Wisconsin). Parasternal, apical, and subcostal views were acquired using 3.5-MHz or M5S transducers. Two- dimensional images and M-mode and Doppler data were digitally stored for off-line analysis (EchoPAC 201.0.0, General Electric Vingmed Ultrasound). MR severity was assessed using a multiparametric approach (7,9). EROA was measured using the PISA method, and RVol was derived by multiplying EROA times the MR velocity time integral. Severe MR was defined as EROA ≥20 mm2 and/or RVol ≥30 ml/beat (7, 8, 9). LV end- systolic volume (ESV) and LVEDV were measured in the apical 2- and 4-chamber views and calculated using the Simpson biplane method (13). Subsequently, LV ejection fraction (EF) was derived as stroke volume (SV) (calculated as EDV – ESV) divided by EDV. The regurgitant fraction (RF) was calculated by measuring the difference between SV measured at the MV annulus and SV at the LV outflow tract and dividing the difference by SV measured at the MV (10). Although the difference between SV measured at the MV annulus and SV measured at the LV outflow tract represents RVol, in the present study, RVol derived using the PISA method was used. The RVol/LVEDV index was calculated and based on previous report (11). The population was dichotomized as RVol/EDV ratio ≥20% (larger RVol and/or smaller LVEDV) and RVol/EDV ratio <20% (smaller RVol and/ or larger LVEDV) (Figure 1).
Follow-up
Patients underwent follow-up for the primary endpoint of all-cause mortality after the first echocardiogram showing moderate-to-severe and severe MR. Survival data were obtained from the departmental cardiology information system (EPD-Vision 11.8.4.0, Leiden University Medical Center), which is linked to the governmental death registry database. All patients underwent complete follow-up.
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