Milrinone enhances systolic, but not diastolic function during coronary artery bypass grafting surgery.
OBJECTIVE
To evaluate the effect of milrinone on diastolic function during coronary artery bypass grafting surgery (CABG).


METHODS
Fifty patients undergoing CABG were randomized to receive a bolus and infusion of milrinone or placebo before cardiopulmonary bypass (CPB) until skin closure. Hemodynamic and transesophageal echocardiographic measurements of systolic and diastolic function were obtained. Pulsed wave Doppler measurements of the early (E wave) and atrial components (A wave) of the transmitral (TMF) and transtricuspid (TTF) flows, and systolic (S wave), diastolic (D wave) and atrial components (Ar) of the pulmonary (PVF) and hepatic venous blood flow (HVF) velocities were performed. Early and atrial components of the mitral (Em and Am waves) and tricuspid annulus velocities (Et and At waves) were assessed by tissue Doppler imaging (TDI). Assessment of diastolic dysfunction was graded from normal to severe using a scale score.


RESULTS
Cardiac index and heart rate were higher in the milrinone group compared to placebo after the administration of study drug (2.8 +/- 0.6 vs 2.1 +/- 0.5 L.min(-1)m(-2)) (P < 0.0001) and (67 +/- 8 vs 60 +/- 12 beats.min(-1)) (P < 0.05) respectively. There were no changes in left and right ventricular diastolic dysfunction scores between study groups. Higher PVF S wave, HVF S wave, TTF A wave and At measured by TDI in the milrinone group compared with placebo suggested an improvement in ventricular systolic and atrial contraction.


CONCLUSIONS
Distinct from its effects on systolic function, milrinone administered before CPB is not with associated improved biventricular diastolic function in patients undergoing CABG.
Couture
Pierre
P
Department of Anesthesiology, Montreal Heart Institute, Montréal, Québec, Canada. pierre.couture@icm-mhi.org
Denault
André Y
AY
Pellerin
Michel
M
Tardif
Jean-Claude
JC
D000368:Aged; D001794:Blood Pressure / Q000187:drug effects; D002315:Cardiopulmonary Bypass; D002496:Central Venous Pressure / Q000187:drug effects; D001026:Coronary Artery Bypass; D003971:Diastole / Q000187:drug effects*; D015150:Echocardiography, Doppler; D017548:Echocardiography, Transesophageal; D005260:Female; D006339:Heart Rate / Q000187:drug effects; D006801:Humans; D008102:Liver Circulation / Q000187:drug effects; D008297:Male; D008875:Middle Aged; D020105:Milrinone / Q000494:pharmacology*; D008943:Mitral Valve / Q000000981:diagnostic imaging; D011652:Pulmonary Circulation / Q000187:drug effects; D018401:Sample Size; D013599:Systole / Q000187:drug effects*; D016896:Treatment Outcome; D014261:Tricuspid Valve / Q000000981:diagnostic imaging; D014665:Vasodilator Agents / Q000494:pharmacology*; D016277:Ventricular Function, Left / Q000187:drug effects; D016278:Ventricular Function, Right / Q000187:drug effects
D014665:Vasodilator Agents; D020105:Milrinone