Mitral early-diastolic inflow peak velocity (E)-to-left atrial strain ratio as a novel index for predicting elevated left ventricular filling pressures in patients with preserved left ventricular ejection fraction.

Abstract

Objectives: We sought to explore the relationship between an index of left ventricular diastolic function parameters combined with left atrial strain and the diastolic function of patients with preserved ejection fraction.

Methods: We prospectively enrolled 388 patients with left ventricular ejection fraction (LVEF) ≥ 50%, 49 of whom underwent left heart catherization. Transthoracic echocardiography was performed within 12 h before or after the procedure. Left atrial (LA) strain was obtained by speckle tracking echocardiography. These patients served as the test group. The remaining patients (n = 339) were used to validate the diagnostic performance of the mitral early-diastolic inflow peak velocity (E)-to-left atrial reservoir strain ratio (E/LASr) in left ventricular diastolic dysfunction.

Results: Invasive measurements of LV end-diastolic pressure (LVEDP) demonstrated that the E/LASr ratio was increased in patients with elevated LVEDP [ 2.0 (1.8-2.2) vs 3.0 (2.6-4.0), p < 0.001] in the test group (n = 49). After adjusting for age, mitral A, E/e' ratio and β-blocker use, the E/LASr ratio was an independent predictor of elevated LVEDP and showed good diagnostic performance in determining elevated LVEDP [area under the curve (AUC) 0.903, cutoff value 2.7, sensitivity 74.2%, specificity 94.4%]. In the validation group (n = 339), the E/LASr ratio also performed well in diagnosing elevated left atrial pressure (LAP) (AUC 0.904, cutoff value 3.2, sensitivity 76.5%, specificity 89.0%), while with a cut-off value of 2.7, the E/LASr ratio showed high accuracy in discriminating elevated LAP. In addition, E/LASr was a good index of excellent diagnostic utility (AUC: 0.899 to 0.996) in the categorization of diastolic dysfunction grades. Regarding the clinical relevance of this index, the E/LASr ratio could accurately diagnose HF with preserved ejection fraction (HFpEF) (0.781), especially in patients with "indeterminate" status (AUC: 0.829). Furthermore, an elevated E/LASr ratio was significantly associated with the risk of rehospitalization due to major adverse cardiac events (MACEs) within one year (odds ratio: 1.183, 95% confidence interval: 1.067, 1.312).

Conclusions: In patients with EF preservation, the E/LASr ratio is a novel index for assessing elevated left ventricular filling pressure with high accuracy.