Right ventricular function before and after an uncomplicated coronary bypass graft as assessed by pulsedwave doppler tissue imaging of the tricuspid annulus

ABSTRACT

RV function using myocardial velocities before and after a CABG is unknown. CABG on the beating heart without cardiac- pulmonary bypass [off- pump] has gainad increasing popularity. Improved post operative ventricular function has been cited as an advantage over on- pump surgery. A total of 36 pts [26 male and 10 female] with significant coronary artery disease underwent elective CABG, between March 2005 and June 2006. All had pulsed wave TDI and mmode imaging obtained from the apex, visualising the tricuspid free wall annulus. Amplitude of TV annulus displacement and RV systolic and diastolic velocities were compared before and 5 days after surgery. Regional mitral annular velocities were also studied for comparison. Altogether 21 pts Underwent off- pump CABG. Each subject had a mean 2.6 grafts. All left ventricular regional velocities showed a non significant reduction after surgery. TAM and both systolic [S] and diastolic [E and L] velocities in the RV decreased considerably 5 days after CABG. S 12.6 vs 7.7, E 10.8 vs. 7, A 6.6 vs 9, [p-0.000]. The off- pump group had a similar trend with no evidence of preserved RV function compared to the on- pump group. Systolic and diastolic RV function, as assessed by DTI and TAM decreased significantly after CABG. TDI can provide a simple and noninvasive qualitative method for assessing and monitoring of RV function after surgery. Off- pump CABG cannot prevent this malfunction