Forward stroke volume is predictor of perioperative course in patients with mitral regurgitation undergoing mitral valve replacement

Abstract

BACKGROUND: Decreased left ventricle ejection fraction (LVEF) is a predictor of poor late
outcome in patients with mitral regurgitation (MR). The relationship between pre-operative
forward stroke volume (SV) and right heart parameters and perioperative outcome in patients
with MR has been little studied.

METHODS: Forty patients with severe organic MR, unsuitable for mitral valve repair, who
underwent mitral valve replacement (MVR) were included in the study (50% men, average age
61 ± 9 years). Exclusion criteria were: aortic valve disease, coronary artery disease,
rethoracotomy, stroke, infection or significant perioperative bleeding. Pre-operative detailed
echocardiographic examination was performed. The end-point was post-operative prolonged
intensive care unit (ICU) stay of more than three days because of the need for inotropic support.

RESULTS: Pre-operative NYHA class was 2.6 ± 0.4, mean right ventricular end-diastolic
diameter (RVEDD) was 28.7 ± 4 mm, TAPSE was 20 ± 4 mm, mean right ventricular
systolic pressure (RVSP) was 38 ± 13 mm Hg, left ventricular end-systolic diameter was 43.5 ± 11 mm, left ventricular end-diastolic diameter was 60 ± 11 mm, left ventricular enddiastolic
volume (Simpson) was 155 ± 47 mL, LVEF was 55 ± 11%, mean regurgitation
fraction was 58% and forward SV (measured by Doppler) was 35 ± ± 11 mL. All patients
survived the operation. Mean ICU stay was 3.2 ± 2.9 days (range 1-10 days), mean TISS-28 was
623 ± 293 and mean NEMS 151 ± 85. By univariate analysis, ICU stay was significantly
longer in patients in higher pre-operative NYHA (p = 0.04), lower LVEF (p = 0.01), lower
forward SV (p = 0.001) higher RF (p = 0.01), pre-operative right ventricular dilatation (p = 0.04),
higher RVSP (p = 0.006) and right ventricular dysfunction (p = 0.04). By multivariate
analysis, forward SV (p = 0.002, b = –0.45) and RVEDD (p = 0.02, b = 0.31) were
independent predictors for prolonged ICU stay.

CONCLUSIONS: Pre-operative forward stroke volume and right ventricle size are predictors of
the perioperative hemodynamic status in patients with mitral regurgitation undergoing MVR.

(Cardiol J 2010; 17, 4: 386-389)