Site-dependency of the E/e' ratio in predicting invasive left ventricular filling pressure in patients with suspected or ascertained coronary artery disease

Abstract

Purpose: To test the accuracy of different mitral annular sites of the E/e' ratio in predicting invasive left ventricular filling pressure (LVFP) in patients hospitalized for coronary artery disease (CAD).

Methods: Forty-one patients with suspected or ascertained chronic CAD underwent non-invasive estimation of LVFP the same day as coronary angiography combined with right catheterization for pulmonary capillary wedge pressure (PCWP) assessment. The ratio between E velocity and early diastolic velocity of the mitral annulus (e') was calculated as a surrogate of PWCP by (i) averaging septal and lateral e' (E/e'A2); (ii) averaging septal, lateral, inferior, anterior (E/e'A4); (iii) using the sole septal (E/e'S); or (iv) lateral annulus (E/e'L). Patients were divided in two groups according to the PCWP: 25 with the PCWP <18 mmHg and 16 with the PCWP ≥ 18 mmHg.

Results: The two groups were comparable for gender, body mass index, blood pressure, heart rate (HR), E/A ratio, and deceleration time. The ejection fraction (EF) was lower and left atrial volume index (LAVi) greater (both P < 0.02) in patients with the PCWP ≥ 18 mmHg. They also exhibited higher E/e'S (P < 0.05), E/e'L (P < 0.0001), E/e'A2, and E/e'A4 (both P < 0.005) than patients with the PCWP <18 mmHg. In pooled groups, after adjusting for HR EF and LAVi, E/e'L (β = 0.42, P < 0.01), E/e'A2 (β = 0.32, P < 0.05), and E/e'A4 (β = 0.31, P < 0.05) were all independently associated with PWCP. E/e'L ≥ 16.2 predicted PCWP ≥18 mmHg with the highest diagnostic accuracy (AUC = 0.826), sensitivity (81.3%), and specificity (80%).

Conclusions: In patients with CAD, E/e'L is the most accurate parameter in predicting abnormally increased LVFP.

Keywords: Diastole; E/e′ ratio; Left ventricular filling pressure; Pulmonary capillary wedge pressure; Pulsed tissue Doppler.