Experience of valve replacement under mild hypothermia on pump-beating heart: an analysis of 800 cases

摘要

Objective: To assess the outcome of valve replacement under mild hypothermia on pump-beating heart and to discuss the risk factors of cardiac valve surgery. Methods : In the period from November 1997 to May 2003, a total of 800 cases of valve replacement were carried out in our institute. The clinical data were reviewed and the technique of mild hypothermia and pump- beating heart to replace cardiac valve was described in detail. Results: 800 patients, 308 male and 492 female, with age range from 8 to 66 years, weighing 19 to 88 kg, underwent operation. The average cardiopulmonary bypass time was (109.38 ± 40. 64) min, the average clamping time of the vena cava was (77.87 ± 27.99 ) min and the average mechanical ventilation time was (17.78 ± 12.21) h. There were 17 patients died in the early postoperative stage with an early mortality rate of 2.13% . The causes of death were failure in the weaning of extracorporeal circulation in 2 cases, severe low output syndrome in 3 cases, ventricular fibrillation in 3 cases, obstruction of coronary ostium of mechanical prosthetic valve in 1 case, hepatic failure in 2 cases, pulmonary failure in 1 case, multiorgan failure in 4 cases, and prosthetic valve dysfunction in 1 case. Severe postopertive complications occurred in 51 cases (6.375%), which included reexplora-tion because of excessive bleeding in 16 cases (2.0%) , lavage of poststernal infection in 2 cases (0.25%) , postoperative strike in 7 cases (0.875% ) , pulmonary failure in 5 cases (0.625% ) , hepatic failure in 4 cases (0.5% ) , multiorgan failure in 11 cases (1.375%), ventricular arrhythmia in 5 cases (0.625%) and peripheral circulation failure in 1 case (0.125% ). Conclusion: Mild hypothermia and pump-beating heart result in satisfying clinical outcome in patients undergoing valve replacement. The integrated sequenced deairing procedure ensures the avoidance of air embolism during operation. Pump- beating heart technique offers a safe and practical option especially in patients with severe critical valvular disorder.