Long-term results of left ventricular reconditioning and anatomic correction for systemic right ventricular dysfunction after atrial switch procedures

OBJECTIVES: Systemic right ventricular failure after atrial switch procedures for transposition of the great arteries has been addressed at Melbourne's Royal Children's Hospital (1981-1993) and the Cleveland Clinic Foundation (1993-2001) with reconditioning of the morphologically left ventricle by means of pulmonary artery banding followed by an arterial switch operation and an atrial reseptation. METHODS: Thirty-nine patients (Royal Children's Hospital, 19; Cleveland Clinic Foundation, 20) with a median age of 10.8 years (range, 13 months-24 years) entered this protocol a median of 10.3 years (range, 0.5-24 years) after an atrial switch procedure. RESULTS: The median duration of pulmonary artery banding was 13 months (range, 0.5-5.4 years). Ten (28%) patients responded unfavorably to morphologically left ventricular reconditioning (5 mortalities: 4 transplantations and 1 PAB still in place). Twenty-four (83%) of the 29 patients who underwent an atrial switch operation and atrial reseptation survived. During a median follow-up period of 8.2 years (range, 1-16 years), 3 patients had cardiac-related deaths. All 18 long-term survivors are asymptomatic. At last echocardiographic evaluation, the morphologically left ventricular function was normal or mildly decreased in 16 (89%) patients, and all had normal or mildly decreased systemic right ventricular function with no or mild tricuspid regurgitation. Age greater than 12 years was associated with a greater probability of morphologically left ventricular failure and not completing the protocol (P =.02) and a higher operative mortality at anatomic correction (P =.02). CONCLUSIONS: Morphologically left ventricular reconditioning and an anatomic correction protocol should be integrated into a cardiac transplantation program when treating patients with morphologically right ventricular failure after Mustard and Senning procedures. It is an alternative to cardiac transplantation in selected patients, with good long-term results. The response to morphologically left ventricular reconditioning past adolescence is inconsistent.     

Long-term results of arterial switch operation

Surgical results and late outcome in 202 patients who had undergone arterial switch operation from 1984 to 1997 were investigated. Actuarial survival was 90.6% at 10 years and 90.0% at 20 years. Fifty-two patients (25.7%) underwent reoperation for pulmonary stenosis and 7 patients (3.5%) had aortic valve replacement. Freedom from re-intervention was 71.9% at 10 years and 60.4% at 20 years. Using xeno-pericardial patch for pulmonary reconstruction was strong predictor for postoperative pulmonary stenosis. Coronary ischemic event was rare but some patients showed electorocardiogram (ECG) change on exercise and hypoplastic left coronary artery. Cardiopulmonary function was almost normal in long term survivors.     

Total right ventricular exclusion procedure: an operation for isolated congestive right ventricular failure

OBJECTIVE: To prevent possible deleterious effects of right ventricular volume overload on cardiorespiratory function, we developed a total right ventricular exclusion procedure for the treatment of end-stage isolated congestive right ventricular failure. METHODS: Since 1996, this procedure has been performed in 5 patients in New York Heart Association functional class IV: 2 adults with arrhythmogenic right ventricular dysplasia and 3 children with Ebstein anomaly. The entire right ventricular free wall was resected along the atrioventricular groove and then parallel to the interventricular septum, sparing the pulmonary valve and a skeletonized right coronary artery. The orifice of the tricuspid valve was closed with either a polytetrafluoroethylene patch or with its leaflets. The defect of the right ventricular free wall was covered with a polytetrafluoroethylene patch in the 2 patients with arrhythmogenic right ventricular dysplasia and directly closed with the remnant of the free wall in the 3 children with Ebstein anomaly. After resection of a redundant right atrial wall, coronary sinus blood flow was rerouted into the left atrium through an atrial septal defect. A total cavopulmonary connection was constructed in 4 patients and a bidirectional superior cavopulmonary anastomosis in 1 infant. The heart was controlled with a DDD pacemaker in 3 patients. RESULTS: The patients were extubated at a mean of 14 hours postoperatively (range, 1-38 hours). There were no early or late deaths. At follow-up, ranging from 8 to 57 months, the mean cardiothoracic ratio had decreased from 74% +/- 7% before the operation to 52% +/- 6% (P <.01). All patients are in functional class I. Neither of the patients with arrhythmogenic right ventricular dysplasia have had attacks of ventricular tachycardia nor are they using antiarrhythmic medication. CONCLUSIONS: The total right ventricular exclusion procedure provides effective decompression of the lung, as well as the left ventricle, and may result in more effective volume loading of a surgically created single ventricle with increased systemic output. We believe that this new surgical option offers rescue treatment for isolated end-stage right ventricular failure in critically ill patients.     

Early and midterm results of the arterial switch operation for transposition of the great arteries in Japan

A total of 267 infants and children who underwent the arterial switch operation for transposition of the great arteries in the 6 years before Jan. 1, 1988 in six main Japanese institutions were entered into this review. The current status of patients surviving more than 1 year after the operation were evaluated along with early operative results. One hundred forty-six patients had an intact ventricular septum, 103 had a significant ventricular septal defect, and 18 had so-called Taussig-Bing anomaly of the transposition type. Eighteen patients were less than 28 days of age, 73 were 1 to 5 months of age, and 176 were older than 6 months of age at the time of operation. The overall mortality rate was 35% in the first 3 years and 12% in the more recent 3 years. There was a significant difference between the overall mortality rate of primary and two-stage repair (22% versus 10%, p = 0.047) in patients with intact ventricular septum. The overall mortality rate in patients with type B or C coronary arteries of Yacoub, and Radley-Smith's classification was significantly higher than that of other types of arteries (86% versus 18%, p = 0.0001). A total of 156 patients survived more than 1 year after the operation, and 44 children (28%) were noted to have supravalvular pulmonary stenosis (greater than 20 mm Hg). This complication was more common in patients operated on in the newborn period. Trivial or mild aortic regurgitation was noted in 29 patients (19%) and was more common in patients with two-stage than with primary repair (24% versus 14%). Aortic regurgitation was significantly more prevalent in patients in whom coronary arteries were implanted into slits or U-shaped defects than in those whose arteries were implanted into punched-out holes made on the pulmonary root (28% versus 8%, p = 0.049). Normal sinus rhythm was present in 97% of 154 patients and left ventricular ejection fraction was within the normal range in 97% of 115 patients at catheterization 1 to 5 months after the operation.     

Segmental wall-motion abnormalities after an arterial switch operation indicate ischemia

We prospectively studied 29 consecutive neonates undergoing an arterial switch operation to determine if segmental wall motion abnormalities (SWMA) represented myocardial ischemia. Intraoperative transesophageal echocardiogram was recorded at baseline and twice after cardiopulmonary bypass. Cardiac troponin I (cTnI) levels were measured before sternal incision and 3, 6, 12, 24, 48, and 72 h after removal of the aortic cross-clamp. Immediate postoperative Holter and 15-lead electrocardiograms (ECG) were evaluated for ischemia. Transthoracic echocardiograms were obtained before hospital discharge. At bypass termination, immediately after protamine administration, segmental wall motion was normal in nine neonates and abnormal in 20. SWMA were transient in five and present at the time of chest closure in 15 neonates. Neonates in whom SWMA were present at chest closure had more segments involved than those in whom SWMA were transient (P > 0.001). Neonates with SWMA at chest closure had higher cTnI levels postoperatively versus neonates with normal wall motion (P = 0.02). Postoperative ECG data were available in 26 neonates. There was ECG evidence of myocardial ischemia in two of eight neonates with normal wall motion, one of five with transient SWMA, and nine of 13 with SWMA at chest closure. CTnI levels at 12, 24, and 48 h and intraoperative SWMA were predictive of postoperative SWMA. We believe these data indicate that SWMA, which persist at the completion of an arterial switch operation, and which are present in multiple myocardial segments, correlate with myocardial ischemia. Further follow-up of these patients is needed to determine if increased intraoperative myocardial ischemia correlates with long-term outcomes.     

Intrapericardial diaphragmatic hernia after arterial switch operation

Intrapericardial diaphragmatic hernia after median sternotomy for cardiothoracic procedures is a rare complication. We describe an interesting case of diaphragmatic hernia in a 6-month-old girl presenting as cardiac tamponade, 4 months after an arterial switch operation. The diaphragmatic defect was iatrogenic and emphasizes the danger of inadvertent diaphragmatic injury during cardiac operations.     

Coronary revascularization after arterial switch operation.

We report two cases presenting bilateral coronary artery obstruction after arterial switch operation. The first patient underwent bilateral internal thoracic artery grafting to the left and right coronary arteries. The other patient, presenting a single coronary ostium, underwent surgical coronary ostial angioplasty in concomitance to proximal arterioplasty of both coronary arteries employing a single "pantaloon" shape autologous pericardial patch. Both patients survived and, at 1 year and 9 months after the coronary revascularization procedures, the coronary angiography demonstrated a good patency of the internal thoracic grafts and excellent ostial plasty results, respectively. A complete literature review of patients undergoing different coronary revascularization procedures after arterial switch operation is reported.     

Aortic valve repair after arterial switch operation

A patient with transposition of the great arteries and a ventricular septal defect underwent an arterial switch operation 15 months after pulmonary artery banding. At 12 years of age, severe neoaortic valve regurgitation, due to dilated aortic sinuses and poor leaflet coaptation, developed. Aortic valve repair involved placement of subcommissural sutures, elliptical excision and tailored reduction of two anterior aortic sinuses, with triangular patch expansion of the proximal ascending aorta. A good result was obtained.     

Technical modification and late results of arterial switch operation

The success of arterial switch operations for transposition of the great arteries largely depends on faultless coronary translocation and subsequent sufficient myocardial perfusion. Occurrence of late coronary obstructions after arterial switch operation was often reported. We developed the bay window technique as a useful adjunct to prevent coronary complications. Late results of this technique are described. No coronary events occurred (i.e. inclusive of coronary stenosis, myocardial infarction, and coronary death). The bay window technique is an innovative and simple surgical adjunct for translocating complex coronary arteries.     

Creation of an atrial septal defect for acute postperfusion right ventricular failure

Acute postperfusion right ventricular failure following mitral and aortic valve replacement in a patient with severe double-valve incompetence secondary to endocarditis is presented. The situation was reversed by creating an atrial septal defect that decompressed the right ventricle and increased left ventricular filling pressure.     

Late coronary artery lesions after neonatal arterial switch operation: results of surgical coronary revascularization.

OBJECTIVE: To evaluate the results of surgical revascularization in children with coronary artery lesions following neonatal arterial switch operation (ASO). METHODS: Among 755 neonates who underwent ASO, there were 713 late survivors (94%). Coronary lesions were detected in 34 patients (5%). Coronary revascularization was carried out in 19 children (mean age: 5.6+/-3.2 years) in whom myocardial ischemia was demonstrated by myocardial perfusion imaging studies. Coronary lesions involved the left main coronary artery in 14 cases, the left anterior descending artery in 3, and the right coronary artery in 2. Sixteen patients had coronary angioplasty (left main coronary artery in 11, left anterior descending artery in 3, right coronary artery in 2). Two patients underwent a mammary bypass and one had a saphenous vein proximal bypass. RESULTS: There was no mortality or coronary event. Mean follow-up was 6.3+/-2.8 years. Patency of coronary repair was demonstrated in all patients; however, in one child with angioplasty of the left main coronary artery, there was a residual stenosis of the left anterior descending artery, and reoperation with a mammary bypass was required. Myocardial perfusion imaging was performed in 18 patients; myocardial perfusion was normal in 16 and 2 had minimal residual perfusion defects. Treadmill exercise testing was performed in 11 patients and was normal in all. CONCLUSIONS: (1) Following ASO, coronary lesions are not uncommon and they are progressive. Routine and sequential coronary evaluation is necessary. (2) Coronary revascularization can be achieved using coronary angioplasty in most cases. Mammary bypass may be used in selected circumstances. Normal myocardial perfusion is restored in most patients.     

Right ventricular outflow tract obstruction after arterial switch operation for the Taussig-Bing heart.

OBJECTIVE: Incidence of right ventricular outflow tract obstruction (RVOTO) may be suspected to be higher after arterial switch operation (ASO) for Taussig-Bing heart than after ASO for transposition of the great arteries (TGA), as Taussig-Bing anomaly is frequently associated with aortic arch obstruction and subvalvular aortic stenosis. We evaluated the risk to develop RVOTO after ASO for Taussig-Bing heart. METHODS: The 34 Taussig-Bing cases who underwent ASO from 1984 to 2005 were reviewed. RVOTO was defined as peak echo-gradient >or=30 mmHg across right ventricular outflow tract. Kaplan-Meier method was used to estimate time-related events. RESULTS: Subaortic stenosis was resected in 25 patients, 20 of whom (80%: 20/25) were discharged from hospital free from RVOTO. There was one early death: 2.9% mortality. Three patients died late. Actuarial survival was 85.1%+/-7.0% from 54 month onwards. Eleven survivors (36.7%: 11/30) experienced postoperative RVOTO. Obstruction was seen in 82% (9/11) of cases at subvalvular and/or valvular level. Surgery (n=4) or percutaneous intervention (n=2) was required in six patients. Patients discharged from hospital with RVOTO (n=8) were more likely to undergo reintervention for RVOTO (p=0.026). Freedom from reintervention for RVOTO decreased rapidly in the first two years to 86.5+/-6.3%, slowly thereafter (80.4+/-8.4% at year 7) and stabilized at 70.3+/-11.9% from year 11 on. Risk for RVOTO occurrence was 23.5+/-7.3% early after repair and progressively increased to level out at 53.6+/-11% at year 11. Patients who underwent subaortic resection were more likely (p=0.023) to be free from RVOTO occurrence or development. In the period under review, for patients who underwent ASO for simple (n=355) and complex (n=92) TGA, reoperation rate for neopulmonary stenosis was 0.3% (1/355) and 5.4% (5/92), respectively, to be compared to 11.8% (4/34) RVOTO rate of reoperation for Taussig-Bing heart in this study. CONCLUSIONS: Postoperative right-sided obstruction occurs more frequently after ASO repair of Taussig-Bing heart than after TGA arterial switching, leading to higher reintervention rate. Resection of the commonly associated subaortic stenosis often prevents RVOTO development.     

Extracorporeal right to left atrial bypass to treat right ventricular failure

Graft right ventricular failure after heart transplantation, secondary to preoperative functional pulmonary hypertension, was successfully managed in a 49-year-old patient using an extracorporeal right to left atrial bypass. We comment on the case and discuss the type of mechanical assistance used.     

Unusual complication of arterial switch operation: ventricular septal aneurysm treated with surgical ventricular restoration.

Despite current low overall perioperative mortality, ischemic complications due to coronary artery translocation remain the most unwanted early complication of the arterial switch operation. We describe the case of a boy who underwent, at five days of age, one-stage arterial switch operation for transposition of the great arteries with repair of ventricular septal defect and coarctation of the aorta. Early postoperative course was complicated by severe ischemic left ventricle (LV) dysfunction and development of a ventricular septal aneurysm. At four years of age he underwent successful surgical ventricular restoration associated with implantation of a biventricular pacing, with complete resolution of heart failure symptoms.     

Midterm results after arterial switch operation for transposition of the great arteries: a single centre experience

ABSTRACT: BACKGROUND: The arterial switch operation (ASO) has become the surgical approach of choice for d-transposition of the great arteries (d-TGA). There is, however an increased incidence of midterm and longterm adverse sequelae in some survivors. In order to evaluate operative risk and midterm outcome in this population, we reviewed patients who underwent ASO for TGA at our centre. METHODS: In this retrospective study 52 consecutive patients with TGA who underwent ASO between 04/1991 and 12/1999 were included. To analyze the predictors for mortality and adverse events (coronary stenoses, distortion of the pulmonary arteries, dilatation of the neoaortic root, and aortic regurgitation), a multivariate analysis was performed. The follow-up time was ranged from 1--10 years (mean 5 years, cumulative 260 patient-years). RESULTS: All over mortality rate was 15.4 % and was only observed in the early postoperative period till 1994. The predictors for poor operative survival were low APGAR-score, older age at surgery, and necessity of associated surgical procedures. Late re-operations were necessary in 6 patients (13.6 %) and included a pulmonary artery patch enlargement due to supravalvular stenosis (n = 3), coronary revascularisation due to coronary stenosis in a coronary anatomy type E, aortic valve replacement due to neoaortic valve regurgitation (n = 2), and patch-plasty of a pulmonary vein due to obstruction (n = 1). The dilatation of neoaortic root was not observed in the follow up. CONCLUSIONS: ASO remains the procedure of choice for TGA with acceptable early and late outcome in terms of overall survival and freedom of reoperation. Although ASO is often complex and may be associated with morbidity, most patients survived without major complications even in a small centre.     

Long-term results of cardiac and general health status in children after neonatal arterial switch operation

BACKGROUND: The purpose of this study was to assess cardiac and general health status 8 to 14 years after neonatal arterial switch operation for transposition of the great arteries. METHODS: Sixty unselected children with intact ventricular septum (78.3%) or ventricular septal defect (21.7%) without or with aortic isthmic stenosis (5.1%) were examined 10.5 +/- 1.6 (mean +/- SD) years after neonatal switch and 5.3 +/- 1.6 years after mid-term evaluation. Complete clinical examination, standard and 24-hour Holter electrocardiogram, M-mode, 2D-, Doppler, and color Doppler echocardiography were performed. Results were compared with normal values and to mid-term follow-up results. RESULTS: Rates of reoperation after arterial switch operation and operation to correct concomitant coarctation were 3.3% and 5.1%, respectively. No patient needed medication, and 93.3% had no limitation of physical activity. All children had normal height and weight; 31.6% had abnormal thoracic configuration after median sternotomy. Most patients (91.7%) were in sinus rhythm. Incidence of complete right bundle branch block (10.0%) was unchanged, as was prevalence of ectopic activity (occasional atrial ectopy 20.0%, ventricular ectopy: occasional 21.7%; frequent 1.7%). Left ventricular dimensions and shortening fraction did not change over time. Diameters of neo-aortic valve annulus and neo-aortic root did not increase, and z-scores decreased between mid-term and present evaluation. Incidence of neo-aortic insufficiency was 13.3% and remained unchanged in comparison with the pre-examination value. Neo-aortic stenosis was not seen. Compared with mid-term follow-up, incidence (41.6%) and degree of supravalvular pulmonary stenosis increased. CONCLUSIONS: Good cardiac results persist 10 years after neonatal arterial switch operation for transposition of the great arteries. Encouraging findings include preservation of left ventricular function, low incidence of rhythm disturbances, lack of further neo-aortic root dilatation, and unchanged incidence of neo-aortic insufficiency compared with mid-term follow-up. Increased incidence and degree of supravalvular pulmonary stenosis are of concern.