ABSTRACT
Background: Elevated left ventricular filling pressures are the main physiological consequence of diastolic dysfunction and carry a prognostic significance in different cardiovascular diseases including coronary artery diseases, and cardiomyopathies. Filling pressures are considered elevated when the mean pulmonary capillary wedge pressure is >12mmHg or when the left ventricular end diastolic pressure is >/= 16 mm Hg. a reliable noninvasive method for the estimation of LVEDP is needed
Objective: The aim of this study was to evaluate the correlation between the Tissue Doppler Imaging derived E/e ratio, and Left Ventricular End Diastolic Pressure [measured during left ventricular catheterization] in patients with significant Coronary artery Disease, and to identify the optimal cutoff value of the E/e ratio to predict elevated LVEDP
Patients and Methods: This study included 87 patients scheduled for elective coronary angiography at Ibn-Albitar Hospital catheterization laboratory between December 2012 and April 2013.Transthoracic echocardiography was performed to all patients within 2 hours before left heart catheterization, using Philips echocardiography system and S5-1 probe. Mitral valve inflow velocities were assessed by Pulsed-wave Doppler performed in the apical 4-chamber view. Ejection fraction [EF] was measured with biplane Simpson's method from the apical 4-chamber view. PW TDI was performed in the apical 4-chamber view to measure mitral annular velocities from the medial and lateral mitral annuli
Results: The mitral inflow velocities [E, and A] were not correlated to LVEDP while the E/A ratio had a weak positive and the DT of the E wave had a weak negative correlations with LVEDP. E/e ratio showed intermediate to good positive correlation with LVEDP especially those derived from the medial mitral annulus. The correlation between E/e ratio and LVEDP was similar in the patients with or without significant CAD. The ROC curve showed that the cutoff point of E/ e ratio for predicting LVEDP higher than 15mm Hg was from medial mitral annulus > 15 [sensitivity 77.5 %, specificity 84.6%; P<0.001] and from lateral mitral annulus >10 [sensitivity 79 %, specificity 80.3 %; P < 0.001]. On subgroup classification according to EFs, the E/e medial showed significant but weaker correlation with LVEDP in patients with EF >/= 50%, as compared to patients with EF < 50 %. E/e lateral and E/e average had poor correlation with LVEDP in patients with EF >/= 50 %, while they have intermediately significant correlation in patients with EF < 50%
Conclusion: The TDI derived E/e ratio is better than mitral inflow doppler velocities and intervals for predicting elevated LVEDP in patients with or without significant CAD, especially in patients with reduced EF. The E/e medial > 15 and E/e lateral > 10, predict LVEDP > 15 mm Hg with good sensitivity and specificity