Left ventricular ejection fraction using a simplified wall motion score based on mid-parasternal short axis and apical four-chamber views for non-cardiologists

Réal Lebeau; Maxime Robert-Halabi; Maxime Pichette; Alain Vinet; Claude Sauvé; Maria Dilorenzo; Viet Le; Eric Piette; Mathieu Brunet; William Bédard; Karim Serri; Frédéric Poulin

doi:10.1186/s12872-023-03141-x

Left ventricular ejection fraction using a simplified wall motion score based on mid-parasternal short axis and apical four-chamber views for non-cardiologists

BMC Cardiovasc Disord. 2023 Mar 8;23(1):115. doi: 10.1186/s12872-023-03141-x.

Authors

Affiliations

¹ Division of Cardiology, Hôpital du Sacré-Coeur de Montréal, 5400 Gouin Blvd W., Montreal, QC, H4J 1C5, Canada.
² Centre de Rercherche de l'Hôpital Sacré-Coeur de Montréal, Montreal, QC, Canada.
³ Department of Pharmacology and Physiology, Faculty of Medicine, Université de Montréal, Montreal, QC, Canada.
⁴ Department of Emergency Medicine, Hôpital Sacré-Coeur de Montréal, Montreal, QC, Canada.
⁵ Division of Cardiology, Hôpital du Sacré-Coeur de Montréal, 5400 Gouin Blvd W., Montreal, QC, H4J 1C5, Canada. f.poulin@umontreal.ca.

Abstract

Background: There is a need for a convenient, yet reliable method to assess left ventricular ejection fraction (LVEF) with point-of-care ultrasound study (POCUS). We aim to validate a novel and simplified wall motion score LVEF based on the analysis of a simplified combination of echocardiographic views.

Methods: In this retrospective study, transthoracic echocardiograms of randomly selected patients were analysed by the standard 16-segments wall motion score index (WMSI) to derive the reference semi-quantitative LVEF. To develop our semi-quantitative simplified-views method, a limited combination of imaging views and only 4 segments per view were tested: (1) A combination of the three parasternal short-axis views (PSAX BASE, MID-, APEX); (2) A combination of the three apical views (apical 2-chamber, 3-chamber and 4-chamber) and (3) A more limited combination of PSAX-MID and apical 4-chamber is called the MID-4CH. Global LVEF is obtained by averaging segmental EF based on contractility (normal = 60%, hypokinesia = 40%, and akinesia = 10%). Accuracy of the novel semi-quantitative simplified-views WMS method compared to the reference WMSI was evaluated using Bland-Altman analysis and correlation was assessed in both emergency physicians and cardiologists.

Results: In the 46 patients using the 16 segments WMSI method, the mean LVEF was 34 ± 10%. Among the three combinations of the two or three imaging views analysed, the MID-4CH had the best correlation with the reference method (r² = 0.90) with very good agreement (mean LVEF bias = - 0.2%) and precision (± 3.3%).

Conclusions: Cardiac POCUS by emergency physicians and other non-cardiologists is a decisive therapeutic and prognostic tool. A simplified semi-quantitative WMS method to assess LVEF using the easiest technically achievable combination of mid-parasternal and apical four-chamber views provides a good approximative estimate for both non-cardiologist emergency physicians and cardiologists.

Keywords: Left ventricular ejection fraction; POCUS; Wall motion score.

MeSH terms

Echocardiography* / methods
Humans
Retrospective Studies
Stroke Volume
Ventricular Function, Left*