Evaluation of the E/e' Ratio of the Mitral Annulus in Predicting Fluid Responsiveness.

Montreal Heart Institute70 enrolled

Overview

Diastolic function may be evaluated by different measurements on transesophageal echocardiography (TEE). They include mitral inflow velocities obtained by pulsed-wave doppler (PW) : peak early diastolic velocity (E) and late diastolic velocity (A). Mitral annulus velocities, early diastolic (e') and late diastolic (a') are obtained by tissue doppler imaging (TDI). The ratio E/e' reflects left ventricular filling pressure and, as such, might be a predictor of fluid responsiveness. The aim of this study is to evaluate the predictive value of the mitral valve E/e' ratio for fluid responsiveness among patients undergoing coronary bypass graft surgery. Fluid responsiveness being defined as an increase in stroke volume of ≥ 15%. After induction of anesthesia, patients will have their diastolic function evaluated by means of E/e' and other measures. They will then be administered an intravenous bolus of 500 mL of Lactate Ringer® along with passive leg raising (PLR). Stroke volume and fluid responsiveness will be assessed by the thermodilution method (Swan-Ganz catheter) and the FloTrac® device. Fluid responders will be compared to non-responders to evaluate the relationship between E/e' ratio and fluid responsiveness.

Study Type

INTERVENTIONAL

Allocation

Purpose

OTHER

Masking

NONE

Enrollment

Conditions

Left Ventricular Function Diastolic Dysfunction Fluid Responsiveness

Eligibility

Sex: ALLMin age: 18 Years

Medical Language ↔ Plain English

Inclusion Criteria: * Patients \>18 yrs, undergoing elective coronary artery bypass grafting or surgery will be included. Exclusion Criteria: * Significant mitral valvular heart disease (mitral regurgitation ≥ 2/4 or stenosis) * Significant right sided valvular heart disease (tricuspid regurgitation ≥ 2/4) * Intracardiac shunts * Emergency surgery * Non-sinusal rythme * Clinical evidence of decompensated heart failure * Clinical evidence of decompensated pulmonary hypertension * Renal insufficiency with creatinine clairance ≤ 30 cc/min or dialysis * Contraindications to TEE, including esophageal disease or unstable cervical spine * CVP ≥ 15 mm Hg or PCWP ≥ 18 mm Hg immediately before fluid infusion

Outcomes

Primary Outcomes

Mitral valve E/e' ratio for prediction of fluid responsiveness

TEE evaluation of mitral inflow velocities and mitral annulus velocities measured right before fluid administration as a predictor of fluid responsiveness defined as an increase of 15% or more of the stroke volume

Time frame: TEE images taken within the 15 minutes before fluid administration and responsiveness evaluation within the 5 minutes following fluid administration and leg raising

Secondary Outcomes

Pulmonary capillary wedge pressure (PCWP) a-wave to v-wave ratio of the for prediction of fluid responsiveness

a-wave on v-wave ratio of the pulmonary capillary wedge pressure (PCWP) curve for prediction of fluid responsiveness defined as an increase of 15% or more of the stroke volume

Time frame: Waveform measured within the 15 minutes preceding fluid administration and responsiveness evaluation within the 5 minutes following fluid administration and leg raising

Pulse pressure variation (PPV) for prediction of fluid responsiveness

Pulse pressure variation (PPV) measured on arterial pressure curve for prediction of fluid responsiveness defined as an increase of 15% or more of the stroke volume

Time frame: PPV measured within the 15 minutes preceding fluid administration and responsiveness evaluation within the 5 minutes following fluid administration and leg raising

Stroke volume variation (SVV) for prediction of fluid responsiveness

Stroke volume variation (SVV) directly measured by FloTrac/Vigileo® with its intrinsic algorithm for prediction of fluid responsiveness defined as an increase of 15% or more of the stroke volume

Time frame: SVV measured within the 15 minutes preceding fluid administration and responsiveness evaluation within the 5 minutes following fluid administration and leg raising