1082 LEFT VENTRICULAR FUNCTION ESTIMATION: WHEN VOLUMES MEASUREMENT IS NOT FEASIBLE

Abstract

Abstract Background Contrast echocardiography is mainly performed for the assessment of global left ventricular (LV) function, left ventricular ejection fraction (LVEF) and stroke volume (SV) thanks to improved visualization of endocardial LV borders. Neverless in some patients estimation of ventricular volumes could be difficult also with contrast and assessment of LVEF can be really hard. The aim of the study was to find alternative methods for LV function evaluation independent from volume assessment. Methods Patients who underwent a contrast echocardiography between October 2015 and September 2022 were enrolled in the study. A complete transthoracic echocardiography was performed and Sonovue contrast was then injected. End-diastolic and end-systolic LV volume in apex 4 and 2 chamber views, were measured prior and after injecting contrast. Left ventricular outflow tract diameter (LVOTd) was measured and LVOT velocity time integral was traced in order to calculate LVOT VTI Stroke Volume (product of LVOT cross sectional area to the LVOT VTI). LVOT VTI SV obtained during traditional echocardiography was then compared to LV SV calculated as the difference between end-diastolic and end-systolic volume traced after contrast. After intravenous bolus injection of Sonovue pulmonary transit time (PTT) was recorded as contrast agent's transit time from right to left ventricle in apex 4 chamber view (seconds). PTT was then compared to measures of LV function: LVEF with and without Sonovue and LV SV with contrast. Results 149 patients were enrolled in the study, 86 had history of CAD, 31 presented dilatative cardiomyopathy, 5 hypertrophic cardiomyopathy (HMC), 113 had arterial hypertension, and 37 diabetes. Medium BMI was 28. The main indications for contrast echocardiography were measurement of EF and exclusion of thrombi in LV apex. LVOT VTI SV was calculated in 126 patients. In the same patients LVEF Stroke Volume was calculated. A strong correlation (P value < 0.0001) between LVOT VTI SV and LV SV was found (Figure 1). PPT was calculated in 74 patient and in the same patients LVEF with and without contrast (Figure 2) and LV SV were calculated. A strong correlation (P-value <0.048, p-value<0.006 and p-value < 0.046 respectively) was found. Conclusion This study demonstrates that, besides extremely poor acoustic windows, bedside echocardiography, with and without contrast, can be used to estimate LV function using volume-independent methods like PTT and LVOT VTI SV.