Application Of Body-pulmonary Shunt In Surgery Treatment Of Tetralogy Of Fallot

BackgroundTetralogy of Fallot is one of the most common clinical cyanotic congenital heart diseases in China, with high morbidity accounting for 12-14% congenital heart diseases. Its severe symptoms often leave the infected children in poor natural prognosis conditions. In 2003, Kirklin and Bbrratt-Boyes reported that natural mortality rates of tetralogy of Fallot without surgery treatment are 25% for patients below 1 year’s old,40% below 3,70% below 10 and 95% below 40. Therefore, it is widely believed at present that tetralogy of Fallot patients shall be treated with surgery as early as possible. As stressed by Wan Zengwei, there are two subjective preconditions to conduct tetralogy of Fallot surgery:the first being a big enough left ventricle with its end diastolic volume index generally thought to be>30 ml/m2, and the second being well developed lung artery with two major clinical assessment index:McGoon≥1.2 or Nakata index≥150ml/m2. Sole Tetralogy patients with lung artery missing on one side may be treated with first phase surgery given that the above preconditions are fulfilled. If the aforesaid preconditions are not fulfilled, the success rate of radical resection will be lower, causing higher surgery mortality rate and more complication symptoms. Palliative operation shall be considered for the mal-conditioned patients. In recent years, many cardiac centers believe that radical resection is suitable for Tetralogy of Fallot patients of all ages as long as there are clinical symptoms, considering the advancement of pediatric congenital heart disease operation and cardiopulmonary bypass techniques and perioperative management level. However, some research centers believe otherwise:radical resections for infants, especially new born, may cause high mortality rate and complications. Mortality rate and complication rate among patients treated with transannular patch are obviously higher, and surgical rectifications for patients above the age of 1 and weighing more than 10 KG are obviously safer. The phase one surgical risk increases for patients with abnormal coronary artery that may affect the incision repair or patch of abnormal right ventricular outflow tract. Therefore, whether tetralogy of Fallot surgeries should be staged remains to be a focus concerning by every cardiac surgeons.ObjectionTo discuss the application of Body-Pulmonary shunts in surgeries of tetralogy of Fallot, and summarize clinical experiences to direct clinical treatment.MethodsHaving reviewed tetralogy of Fallot patients (285 in total) treated between January 1,2008 and December 31,2010.21 were treated by blalock-taussig shunts, 10 males and 11 females of age between 5 month and 12,3 years and 4 months old in average; eighing between 5 to 22 Kg, (12.06±4.06) Kg in average; individual body surface (0.28-0.87) m2, (0.53±0.14) m2 in average; oxyhemoglobin saturation (56-79)%, (66.3±5.4)% in average. In these cases, there are 1 right thoracotomy artificial vessel bridging surgery between right subclavian artery and right pulmonary artery,10 right thoracotomy artificial vessel bridging surgery between aorta and right pulmonary artery,8 mid front thoracotomy artificial vessel bridging surgery between aorta and right pulmonary artery and 2 mid front thoracotomy artificial vessel bridging surgery between aorta and right pulmonary. Periodical follow-up visits in (11±8) months were conducted to analyze and compare the pre and after surgery oxyhemoglobin saturation, Nakata index, three LVEDVI indexes (calculated with 64 layer CT examination, and data from LVEDVI and cardiac color ultrasound examination) and cardiac color ultrasound and 64 layer CT examination to calculate Nakata index and LVEDVI.SPSS 17.0 is adopted for statistics analysis, with statistics shown in (x±s). T testing of matched data is adopted as statistical method. P<0.05 divergence is statistically significant. Results1. Oxyhemoglobin saturations before and after blalock-taussig shunts are (66.3±5.4)%and (79.8±4.4)%, respectively, P<0.05, with Nakata index being (115.3±11.4)mm2/m2 and(177.1±21.9)mm2/m2, P<0.05 respectively, and LVEDV index being (25.5±3.8) ml/m2 and (33.9±3.5) ml/m2, P<0.05, respectively.2. Nakata index and LVEDVI calculated with cardiac color ultrasound and 64 layer CT examination are (128.8±14.5) mm2/m2,(190.7±39.4) mm2/m2, respectively, and (25.5±3.9) ml/m2 (28.9±3.4) ml/m2, respectively, both P<0.05.3. One patient of mid front thoracotomy artificial vessel bridging surgery died 20 hours after surgery because of hyoxemia due suspiciously to vascular occlusion. One patient of mid front thoracotomy artificial vessel bridging surgery had vascular occlusion within 3 month and went through another right thoracotomy artificial vessel bridging surgery between right subclavian artery and right pulmonary artery. One patient had vascular occlusion after 1 year, but his pulmonary artery index and left ventricle index met requirements, so radical mastectomy was operated. The other 18 patients were healed after radical mastectomy in 4-18 months following the bridging operation.Conclusion1. As a palliative operation to enhance patient’s lung Qpv, oxygenation, development of lung vessels and left ventriculus and to prevent lung angiopathy, blalock-taussig shunts may create conditions for second stage radical mastectomy. And Nakata index and LVEDVI calculated with cardiac color examination and 64 layer CT may direct the surgery.2. Body-Pulmonary shunt may increase success rate of tetralogy of Fallot surgery and reduce risks of post-operation complications.