Performance of a simplified wall motion score index method for emergency physicians to assess left ventricular ejection fraction : prospective study about 65 cases

Objective: The purpose of our study is to evaluate a simple and rapid method for the assessment of left ventricular ejection fraction (LVEF), that can be used by emergency physicians, namely the Simplified Wall Motion Score... [ view full abstract ]

Objective: The purpose of our study is to evaluate a simple and rapid method for the assessment of left ventricular ejection fraction (LVEF), that can be used by emergency physicians, namely the Simplified Wall Motion Score index method (SWMSI). The score is derived from the 17 segment-model that is based on evaluation of regional contractility of the left ventricle obtained from a left short axis parasternal view and an apical view.

Method : This randomized prospective study was carried out in the cardiology department over a period of one month involving patients aged > 16 years who had to undergo a transthoracic echocardiography examination (TTE). The patients had a double Doppler echocardiography examinations.

- An initial echocardiographic investigation was done by an emergency physician who had received a three-month training in Doppler echocardiography. This examination comprised an estimate of LVEF by the SWMSI method following by a global visual estimation (GVE)

- The second echocardiographic examination was performed by an echo-proficient reader. This investigation comprised an estimate of LVEF by successively SWMSI, GVE and by the biplane Simpson’s method BS which constituted our reference method. The concordance of SWMSI estimate with the GVE and BS estimates were calculated in both readers by the inter-class concordance coefficient of Cronbach’s alpha.

Results : Sixty-six patients were involved in the study. Mean age was 56 ± 14 years; sex ratio was 9 males/4 females. The patients were included independently of the degree of alteration of the left ventricle contractility.

- For the emergency physician, the concordance of SWMSI obtained from a left short axis parasternal view and by the biplane simpson’s method was 0.74 (IC 95% = [0.70 – 0.78]; p<10-3) and the concordance of SWMSI obtained from an apical view and by the biplane Simpson’s method was 0.72 (IC 95% = [0.70 – 0.75]; p<10-3) and the concordance of GVE and that obtained by the biplane Simpson’s method were 0.95 (IC 95% = [0.50 – 0.59]; p<10-3).
- For the cardiologist, the concordance of SWMSI obtained from a left short axis parasternal view and that from an apical view and the concordance of GVE and that obtained by the biplane Simpson’s method were 0.95 (IC 95% = [0.92 – 0.98]; p<10-3).

Conclusion : Assessment of LVEF was better performed among emergency physicians with the SWMSI method than with the GVE method independently of the degree of alteration of the left ventricle contractility. The semi-quantitative method should be adopted by emergency physicians for LVEF estimated. Nevertheless, a minimum three-month training in Doppler echocardiography would be necessary.