Background: This study was conducted to assess the efficacy and applicability of on-pump beating heart valvular operations using retrograde coronary sinus perfusion.
Methods: A prospective, randomized study was conducted. A total of 50 patients participated in this study after having been allocated to one of two groups. On-pump beating heart valvular operations using retrograde coronary sinus perfusion as myocardial protection were performed in 25 patients (beating heart procedure group: aortic = 8 patients, mitral = 15 patients, double = 2 patients). Twenty-five patients underwent conventional valvular operation using retrograde continuous warm blood cardioplegia (conventional procedure group: aortic = 9 patients; mitral = 13 patients; double = 3 patients). The remaining operative variables and early outcomes of these procedures were compared. In the beating heart procedure group, myocardial tissue oxygen was measured by near infrared spectroscopy, and partial oxygen pressure of coronary sinus perfusion was also measured.
Results: The visual field of the on-pump beating heart was equal to that of conventional valvular operation, and technical accuracy was not compromised. In the beating heart procedure group, tissue oxygen saturation was maintained at 79% +/- 2%, and partial oxygen pressure of coronary sinus perfusion blood and returned blood were maintained at 383 +/- 29 mm Hg and 38 +/- 2 mm Hg, respectively. Postoperative peak creatine kinase-MB (measured every 3 hours postoperatively) and peak troponin T concentrations were significantly lower than those of conventional procedures (17.5 +/- 7.8 vs 32.1 +/- 9.3 IU/L and 0.12 +/- 0.04 vs 0.21 +/- 0.06 ng/mL, respectively; p < 0.05). There was no operative mortality and no major complications.
Conclusions: On-pump beating heart valvular operation is a good surgical option, and has advantages because conditions for the heart are more physiologic with beating tonus than with cardioplegia.