Outcome Of Patients After Arterial Switch Operation:10 Years Of Experience In A Single Center

Background The arterial switch operation(ASO)has become the procedure of choice for the transposition of great arteries(TGA)and double outlet right ventricle with subpulmonary ventricular septal defect(Taussig–Bing anomaly,TBA).In spite of the excellent outcome in terms of survival,surgical repair is far from anatomical and potential late defects were identified.The supravalvar pulmonary stenosis(SVPS)is widely recognized as the most frequent complication after ASO.It was not until early 20 th century did ASO began to routinely perform in several large heart center in China,and the data of early and midterm outcome of ASO in large populations are still few.Objective To identify the early and midterm outcome in terms of mortality,reoperation and supravalvar pulmonary stenosis(SVPS)in patients underwent ASO and analyze the predictors of mortality,reoperation and moderate or severe SVPS.Methods Between December 2000 and December 2016,168 patients underwent ASO at Wuhan Union Hospital,China were included,patients’ characters,surgical reports and echocardiograms were retrospectively reviewed.The patients were divided into three groups: simple TGA(n=90)with an intact septum,complex TGA(n=71)with a ventricular septal defect or other anomalies,and TBA(n=7).The risk factors were analysised by the multivariate logistic regression and the Cox regression models were employed appropriately.Results(1)94 patients had complete echocardiograms,the median echocardiographic follow-up from ASO was 3.29 years(range,0.25 to 10.24 years).At any time during follow-up,27.7% patients showed an SVPS of mild or more,whereas 12.8% patients of moderate or severe SVPS.At the last follow-up,moderate or severe SVPS was observed in 4.3% patients.The multivariate analysis showed nonpericardial patches(P=0.093)and moderate or severe SVPS at discharge(P=0.021)was the risk factors for moderate or severe SPVS at the last follow-up.(2)From the total cohort,two patients(1.2%)of complex TGA underwent early reoperation because of aneurysmal dilation of the pulmonary patch.For the 141 survivors,the median followup from ASO was 4.19 years(range,0.09 to 10.73 years).Three patients required 4 late reoperation or reintervention.Patients of simple TGA was freedom from reoperation.The freedom from reoperation or reintervention rate was 94.4 ± 2.5% at 5 years.The multivariate analysis showed that age at ASO older than 1 year(P=0.012),aortic arch anomalies(P=0.024),longer duration of mechanical ventilation(P<0.001)as strong predictors for reoperation.(3)From the total cohort,early death occurred in 27 patients.Longer cardiopulmonary bypass(CPB)time(p=0.009)was the predictor of early mortality by multivariate analysis.Late deaths occurred in 3 patients within the first year after ASO.The Kaplan-Meier’s survival rate was 79.4 ± 3.3% at both 1 year and 5 years.By multivariate analysis,situs inversus(P=0.002)was the independent risk factor for mortality.Conclusion It is not recommended to use non-pericardial patches.Patients with moderate or severe SVPS at discharge should be more closely followed.The risk of reoperation is greatly increased in patients with aortic arch anomalies,age at ASO older than 1 year and longer duration of mechanical ventilation.Longer CPB time and situs inversus were risk factors for mortality.