The Study Of Clinical Application Of Doubly Committed Sub-arterial Ventricular Septal Defects Closure Through A Right Subaxillary Thoracotomy And The Postoperative Life Quality In Children

Objective This study aimed to summarize the experience of doubly committed sub-arterial ventricular septal defects(VSDs)closure through a right subaxillary thoracotomy(RSAT)in children,investigate the feasibility of doubly committed sub-arterial VSDs closure through a RSAT and evaluate mid and long-term outcomes of repair of VSDs through a RSAT and the postoperative life quality of the patients.Materials and Methods Section I: 1?Materials:Between Oct.2009 and Sept.2015,clinical data of 78 patients(A Group)who underwent doubly committed sub-arterial VSDs closure through a RSAT and 50 patients(B Group)who underwent doubly committed sub-arterial VSDs closure through median sternotomy were retrospectively analyzed.The patients were from Women and children's Hospital of Qingdao and Affiliated Hospital of Jining Medical College.The patients of “B Group” were selected randomly by “Excel software”.General information of the 128 doubly committed sub-arterial VSDs patients was:70 males,58 females;a mean age of 5.0±2.7 years(range,0.5 to 15 years);body weight 15.3±9.0kg(range,7 to 42kg).Ultrasound cardiogram,electrocardiogram and chest X-ray were examined in all patients preoperatively.All patients had a definite diagnosis of doubly committed sub-arterial VSD preoperatively and precordial systolic heart murmur apparently.All patients were in New York Heart Association(NYHA)cardiac function class I.The inclusion criteria were as follows:(1)precordial systolic heart murmur apparently,(2)doubly committed subarterial VSDs by ultrasound cardiogram,apparent left to right ventricular shunt,noticeable hemodynamic abnormality,left ventricular enlargement by echocardiography,(3)increased heart shadow and ephemeral pneumonia on chest X-ray,(4)left ventricular enlargement or approximately normal by electrocardiogram,and(5)frequent respiratory infection.The exclusion criteria were as follows:(1)respiratory diseases,(2)a history of undergoing right thorax and cardiac procedure,(3)body mass index(BMI)greater than 30kg/m2,(4)moderate to severe aortic regurgitation,(5)severe pulmonary hypertention,and(6)severe hepatic and renal dysfunction,etc.2?Surgical technique:After trachea cannulation and intravenous inhalational anesthesia,(1)The patients of “A Group” were placed in a left 75~90? lateral position.Left axilla was elevated 8~15cm with a cushion according the age and body weight of the patient.The right arm was brought over the head and supported by a sling.A oblique incision between the intersection point of the middle axillary line and the 3rd intercostals space and the intersection point of the anterior axillary line and the 5th intercostals space was made.The length of the incison was in line with the age and body weight of the patient,for infants 4~6cm and children 7~8cm approximately.The subcutaneous tissue was undermined and the anterior border of the latissimus dorsi and posterior border of the ectopectoralis was set free of attachments.Part of the costoscapularis was undermined and the muscles were mobilized to expose the 5th rib,with the preservation of the long thoracic nerve,the breast and muscle-sparing.The intercostal muscles were separated from the 5th rib and the pleura was entered in the 4th intercostal space.Two retractors(Jinzhong Medical Instrument Co.,ltd,Shanghai,China)were used to retract both structures together.The tidal volume was reduced and the right lung was deflated to a certain extent.Right lung was retracted posteriorly with a wet sponge to expose the pericardium and protect the lung.The pericardium was opened parallel 2cm anterior to the phrenic nerve generally,upward to the reflection of ascending aorta and the pericardium and downward to the reflection of venae cava inferior and the pericardium.The thymus gland was removed if necessary.Right lung was covered with a wet sponge.The heart was dragged and elevated to right side of the operative field by means of the sutures set through the pericardium,contributing to the exposure of the heart and defect.After heparinization,the cardiopulmonary bypass(CPB)was established routinely through the ascending aorta,the superior venae cava and inferior venae cava.The cannulation of the ascending aorta was one of the critical steps during the establishment of CPB.The adventitia of ascending aorta root was dragged downward by a forceps.The tip of the cannula was nipped by a forceps,contributing to the cannulation of the ascending aorta.After the establishment of the CPB,the interval between ascending aorta and main pulmonary artery was undermined.The cardioplegia(St.Thomas)was affused antergradely from the root of the ascending aorta.The procedure was accomplished under mild hypothermia CPB.The left heart venting was inserted through the patent foramen ovale(PFO)or interauricular septum.After cardioplegia arrest,a wet sponge was placed in the pericardial cavity beneath the heart and the defect was positioned in a shallower area accordingly,contributing to get better visualization of the infundibulum of right ventricle and doubly committed sub-arterial VSD.The technique of VSDs closure was similarly to that of median sternotomy.Most of the defects were approached through the incision of the main pulmonary artery and closed with a piece of dacron patch using a running suture.(1)A doubly committed sub-arterial VSD was approached through the incision of the main pulmonary artery:A transverse incision approximately 1.5~2.5cm in length,1.5~2.0cm above the pulmonary valve annulus,was created in the main pulmonary artery.The distal section of the main pulmonary artery was dragged eccentrically by means of the sutures set through it.Two drag hooks were placed into right ventricular outflow tract(RVOT)through the incision of main pulmonary artery.Appropriate traction of the two drag hooks contributed to exposure the defect,while at the same time trying to avoid excessive traction injury to the myocardium.The pulmonary annulus was dragged by means of the sutures set through it.Thus,a doubly committed sub-arterial VSD was exposed satisfactorily.These important structures should be recognized,which include the annulus of aortic valve,right coronary cusp,the annulus of pulmonary valve and pulmonary valve.A piece of dacron patch of appropriate size was prepared according to the size of the defect.A double needle suture with a piece of pledget started from inferior rim of the defect counterclockwise.There was some difficulty in exposing aortic and pulmonary commissural annulus.Skillful co-operation between the surgeons and adjusting the inclination of the operating bed helped to accomplish the procedure.Dragging the dacron patch with appropriate traction contributed to expose the defect.It was important to put sufficient emphasis on the preservation of the semilunar valves and aortic sinus.A little of cardioplegia affused antergradely from the root of the ascending aorta contributed to identify the annulus of aortic valve.When the suture approached the pulmonary commissural annulus,the other side of the double needle suture proceeded anticlockwise.After accomplishing the closure,the knot was set nearby the pulmonary commissural annulus.The defect was closed directly with one to two pledgetted polypropylene sutures for small defect with a firm rim,with the preservation of the semilunar valves and aortic sinus.Skillful co-operation between the surgeons helped to accomplish the procedure.(2)A doubly committed sub-arterial VSD was approached through the longitudinal incision of RVOT.A longitudinal incision approximately 1.5 to 2.0cm in length,as short as possible,was created in RVOT with the preservation of the branches of right coronary artery.A doubly committed sub-arterial VSD was exposed satisfactorily by means of the sutures set through the incision of RVOT.Generally,it was relatively easy to accomplish doubly committed sub-arterial VSDs closure through the incision of RVOT.The defect was repaired similarly to the technique of approaching through the main pulmonary artery.After the closure of the defect,the incision of the main pulmonary artery or RVOT was closed using a running suture.After the gas in left heart was drove out,a PFO or atrial septal defect(ASD)was closed directly.After the rebeating of the heart,the incision of right atrium was closed using a running suture.The pericardial cavity was closed using an interrupted suture.The chest drainage tube was implanted through the 6th or 7th intercostals space on right midaxillary line.The lung was inflated adequately and repeatedly to eliminate the residual air in the thoracic cavity to reduce the complications such as subcutaneous emphysema and pneumopericardium.For closure,pericostal sutures were placed with the retainment of a normal space between the rib(2)The doubly committed sub-arterial VSD of “B Group”was approached through a median sternotomy.The defect was approached through a median sternotomy as short and low as possible.The thymus gland was removed if necessary.After heparinization,the CPB was established routinely through the ascending aorta,the superior venae cava and inferior venae cava.The procedure was accomplished under mild hypothermia CPB.The defects were approached through the incision of the main pulmonary artery or RVOT.The defect was repaired similarly to the technique of approaching through a RSAT.It was important to put sufficient emphasis on the preservation of the semilunar valves and aortic sinus during the procedure.After the closure of the defect,the incision of the main pulmonary artery or RVOT was closed using a running suture.Additional procedures of concomitant defects:Mild aortic insufficiency,mitral insufficiency and tricuspid insufficiency needed no further repair);The mitral valve commissural plasty was accomplished with the shrinking of the anterior and posterior commissures of the mitral annulus for mild to moderate mitral insufficiency;The tricuspid valve commissural plasty was performed using a De Vega'S plasty with the shrinking of the septal and posterior commissures of the tricuspid annulus for mild to moderate tricuspid insufficiency;PFO or ASD was closed directly or with a piece of autologous patch.For RVOT obstruction patients,a longitudinal incision was created in RVOT.After resection of the hypertrophic muscles,the incision of RVOT was closed directly using a running suture or reconstructed with a patch of autologous pericardium.3?Ulinastatin(10 thousand UI/kg)was pumped into the body through the internal jugular vein after anesthesia induction and before the beginning of CPB and the other 10 thousand UI/kg ulinastatin was mixed into CPB priming solution.Conventional ultrafiltration was applied during the progress of CPB.Modified ultrafiltration was performed after the progress of CPB with the flow rate of 15~20m L/(kg.min)and ultrafiltration time of 10~15min.4?Observational indexes:(1)The CPB time,aortic cross-clamping time,the amount of bleeding,post-operative chest drainage,mechanical ventilation time and intensive care unit(ICU)and hospital stay time were compared between the two groups.(2)All patients were followed up through outpatient service or telephone at 3,6 and/or 12 months after surgery.Ultrasonic cardiogram,electrocardiogram and chest X-ray were examined before discharge and during the follow-up.Satisfactory degree of the patients and their relatives were investigated.(3)The pulmonary function parameters[fraction of inspired oxygen(Fi O2),breathing rate(R),tidal volume(TV),peak of airway pressure(Ppeak),pressure of the pause and insp.cycle off(insp%)] and inflammatory mediators[interleukin 6(IL-6)and interleukin 8(IL-8)] were measured at specific time points[before CPB(T1),30 min after CPB(T2),6h after the surgery(T3)and 12 h after the surgery(T4)].The levels of resistance of air way(Raw),static pulmonary compliance(Cstat),oxygen index(OI)and alveolar-arterial oxygen difference(Aa DO2)were measured as follows:Raw=(Ppeak-Ppause)×0.6×insp%/(TV×F),Cstat=TV/(Ppause-PEEP),OI=Pa O2/Fi O2 and Aa DO2=[Fi O2×(atmospheric pressure-water vapor pressure)-Pa CO2/R]-Pa O2,R(respiratory coefficient)=0.8,which were measured according to the results of blood gas analysis and the pulmonary function parameters.(4)The indexes of myocardial injury[troponin I(c Tn I),creatine kinase isoenzyme(CK-MB),creatine kinase(CK),lactate dehydrogenase(LDH)]and inflammatory mediators [tumor necrosis factor(TNF-?),s ICAM-1,MDA and SOD] were measured at specific time points[before CPB(T1),30 min after CPB(T2),6h after the surgery(T3)and 12 h after the surgery(T4)].Section II: 1?Materials:From Jan.2006,1537 isolated VSD patients underwent surgical repair through a RSAT in Women and children's Hospital of Qingdao and Affiliated Hospital of Jining Medical College cardiac surgery.Between Jan.2015 and Sept.2016,527 patients with isolated VSDs(aged 6~15 years,up to this investigation)who underwent surgical repair through a RSAT were surveyed as“C Group”,while 236 contemporaneous cohorts with isolated VSDs underwent this repair through a median sternotomy were surveyed as“D Group”.The patients were selected randomly by“Excel software”.General information of“C Group”and“D Group”was:295 males,232 females;a mean age of 3.5±1.6 years;body weight 14.5±4.8kg and 124 males,112 females;a mean age of 3.4±1.7 years;body weight 14.3±5.2kg,respectively.2?Observational indexes:The mid-and long-term outcomes of the patients of the two groups were collected.The follow up was accomplished through outpatient service or telephone.Symptoms and physical signs related with primary disease and the outcomes of ultrasonic cardiogram,electrocardiogram and X-ray were observed.Chinese TNO-AZL Children's Quality of Life(TACQOL)questionnaires supported by Public Health College of Tongji Medical College of Huazhong University of Science and Technology were analysed to evaluate the health-related quality of life of the patients.Results All procedures of the patients were performed successfully in this study and incision prolongation or conversion to another approach was not required in “A Group” and “C Group”.No patients of “A Group”and “C Group”had another surgical approach to their defects during the procedure.The short and mid-term follow up outcomes demonstrated no perioperative mortality,no second run of CPB because of a large residual VSD,no reoperation for bleeding,no nervous system ingury,phrenic nerve ingury,pleural effusion,pericardial effusion and poor wound healing or infection occurred in “A Group”and “B Group”.The mid and long-term follow up outcomes showed no death related with cardiac incidents occurred in “C Group”and “D Group”.The follow up rate of “C Group” and “D Group”was 81.88%(357/436)and 81.28%(152/187),respectively.(1)The CPB and aortic cross-clamping time of “A Group” were longer than that of “B Group”.The amount of intraoperative bleeding,postoperative chest drainage,ICU and hospital stay of “A Group”were shorter than that of“B Group”.There was no statistically significant difference in mechanical ventilation time between the two groups.(2)Approximately 82.05%(64/78)defects were approached through the incision of main pulmonary artery in “A Group”,while approximately 82.00%(41/50)defects were approached through the incision of main pulmonary artery in “B Group”.There was no statistically significant difference between the two groups.(3)The postoperative short and mid-term follow up outcomes revealed that there was no significant difference in complications after surgery between “A Group”and “B Group”.(1)Postoperative echocardiography revealed 1 patient with small residual shunt(<2mm)and 1 patient with mild mitral regurgitation in “A Group” and 1 patient with small residual shunt(<2mm)in“B Group”.The incision length was 6.7±1.5cm(range,5.0 to 8.0cm).Follow-up period was 37±27.5 months(range,6 to 72 months).Two small residual shunts detected on echocardiography healed at the 6 and 12 months follow-up visit,respectively.No evidence of the regression of cardiac function was detected during the follow-up.The patients were all in New York Heart Association cardiac function class I.The thoracic incision healed properly in all patients.No chest deformity and asymmetrical development of the breast has been found in“A Group”.The cosmetic advantage of the RSAT is noticeable,which is often invisible under the armpit.All patients of “A Group”were satisfied with the cosmetic results during the follow-up.(4)The indexes of pulmonary function ingury parameters(Cstat?Raw?Aa DO2?OI)after cardiopulmonary bypass were significant different from that of primary levels.There was no significant difference in those indexes at each time points(T2?T3?T4)between the two groups.The indexes of myocardial ingury parameters(c Tn I?CK-MB?CK?LDH)after cardiopulmonary bypass were significant different from that of primary levels.There was no significant difference in those indexes at each time points(T2?T3?T4)between the two groups.(5)The mid and long-term follow up results showed that there were no late deaths related with cardiac defect during the follow-up in “C Group” and “D Group”.All patients of “C Group”felt well and were satisfied with the cosmetic results.The cosmetic advantage of the RSAT is noticeable,which is often invisible under the armpit.No asymmetrical development of the breast and chest deformity(scoliosis,pigeon breast or chonechondrosternon)has been found in “C Group”.The incision of “D Group”was located in anterior median chest with apparent scar.The rate of chest deformity in “D Group” was 1.7%(4/236),which include pigeon breast 3 cases and chonechondrosternon 1 case.There was statistically significant difference in chest deformity between the two groups(c2=389.235,p=0.000).There was no statistically significant difference in the results of accessory examinations(ultrasonic cardiogram,chest X-ray and electrocardiogram)between the two groups.(6)Chinese TNO-AZL Children's Quality of Life(TACQOL)questionnairesdemonstrated the scores of “C Group”were higher than that of “D Group”in the domains “Positive Emotion,Self-care Ability,Cognitive Functioning,Motor Functioning and Physical Complaints and the Whole”.There was statistically significant difference in these domains.There was no statistical difference in “Negative Emotion and Communication Ability” between the two groups.Conclusions(1)In our opinion,suitable operative position,entrance to the thoracic cavity obtained through the 4th intercostal space and appropriate traction of the sutures set through suitable positions,better visualization of doubly committed subarterial VSDs could be achieved.With accumulated experience of the right subaxillary thoracotomy applied in open heart surgery and the technique of doubly committed subarterial VSDs exposure through this approach,the right subaxillary thoracotomy provides an feasible alternative for doubly committed subarterial VSDs closure in children.(2)The right subaxillary thoracotomy can be performed with less invasiveness,faster recovery and favorable cosmetic results for doubly committed subarterial VSDs closure in children.(3)Combined conventional ultrafiltration and modified ultrafiltration and ulinastatin used in the procedure provides satisfactory myocardial and pulmonary function protection in pediatric open heart surgery during cardiopulmonary bypass.(4)Mid and long-term postoperative follow up outcomes demonstrated that surgical repair of VSDs through a right subaxillary thoracotomy can provide superior results which include less complications,apparent cosmetic advantage of the incision,higher degree of satisfaction and better health-related quality of life for pediatric patients.