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.

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.