E-point septal separation: a bedside tool for emergency physician assessment of left ventricular ejection fraction.

OBJECTIVES: Rapid assessment of left ventricular ejection fraction (LVEF) may be critical among emergency department (ED) patients. This study examined the predictive relationship between ED physician performed bedside mitral-valve E-point septal separation (EPSS) measurements to the quantitative, calculated LVEF. We further evaluated the relationship between ED physician visual estimates of global cardiac function (GCF) and calculated LVEF values.

METHODS: A prospective observational study was conducted on a sequential convenience sample of patients receiving comprehensive transthoracic echocardiography (TTE). Three ED ultrasound fellows performed bedside ultrasound examinations to obtain both EPSS measurements and subjective visual GCF estimates. A linear regression analysis was conducted to examine the relation of EPSS to the calculated LVEF from the comprehensive TTE. Agreement (modified Cohen κ) between ED ultrasound fellow GCF estimates and the calculated LVEF was also assessed.

RESULTS: Linear regression analyses revealed a significant correlation (r=0.73, P<.001) between bedside EPSS and the calculated LVEF. The sensitivity and specificity of an EPSS measurement of greater than 7 mm for severe systolic dysfunction (LVEF≤30%) were 100.0% (95% confidence interval, 62.9-100.0) and 51.6% (95% confidence interval, 38.6-64.5), respectively. Subjective estimates of GCF were moderately correlated with calculated LVEF (Cohen κ=0.58).

CONCLUSIONS: Measurements of EPSS by ED physicians were significantly associated with the calculated measurements of LVEF from comprehensive TTE. Subjective visual estimates of GCF, however, demonstrated only moderate agreement with the calculated LVEF. An EPSS measurement greater than 7 mm was uniformly sensitive at identifying patients with severely reduced LVEF.