Twenty-five years' experience with the arterial switch operation.

OBJECTIVE: The arterial switch operation was introduced in 1976 to correct transposition of the great arteries and has since replaced atrial palliation. This study examines the long-term outcomes of the arterial switch operation. METHODS: Included in the study were 195 patients who underwent the arterial switch operation from 1977 through June 2000. Patients were evaluated for functional class, pulmonary stenosis, left ventricular function, arrhythmias, aortic sequelae, and coronary disease. RESULTS: Overall perioperative mortality was 15%, but rates dropped in the last 5 years to 4% for complex transposition and 0% for simple transposition. Of 151 survivors, 2 died late; 1 died of persisting pulmonary hypertension and 1 died of ventricular fibrillation after coronary pathologic changes. At last follow-up, a total of 145 patients were in New York Heart Association functional class I and 4 patients were in class II. The most frequent complication was pulmonary stenosis, necessitating 45 reinterventions in 26 patients. Left ventricular dysfunction was noted in 5 patients. Arrhythmias were seen in 5 patients: 2 patients had ventricular fibrillation (1 died and 1 required a defibrillator implantation), 1 had sick sinus syndrome, 1 had atrial flutter, and 1 had a single attack of supraventricular tachycardia. Aortic valve incompetence was absent or trivial in 146 patients, 3 had mild incompetence, 1 had moderate incompetence, and 1 had severe incompetence. Coronary sequelae were found in 5 of the 61 patients who underwent angiography. CONCLUSION: Long-term clinical outcome of the arterial switch operation is good, and perioperative mortality is now low. Morbidity is dominated by pulmonary stenosis and coronary artery disease, with the potential for lethal arrhythmias.

Fate of the aortic root after arterial switch operation.

OBJECTIVE: Concerns have been voiced about possible dilation and insufficiency of the neo-aortic valve after the arterial switch operation (ASO). AIMS: To determine growth of the neo-aortic valve and the aortic anastomosis after ASO and the prevalence of insufficiency or stenosis. PATIENTS AND METHODS: Since 1977, 144 consecutive patients (pts) underwent ASO for transposition of the great arteries (TGA). Median follow-up was 8.65 years (0.1--22.5 years). Simple TGA was present in 97 pts and 47 had TGA with ventricular septal defect (VSD). Detailed echocardiography included measurements of aortic diameter at four levels. The 608 measurements were compared with published normal values. RESULTS: The mean aortic valve z-score was 1.5, without significant change with age (P=0.75). Under 4 months, mean valve z-score was 0.63+/-2.20, between 5 and 12 months 2.56+/-2.30 (P<0.0001). Gradual growth occurs thereafter. The aortic sinus follows an identical growth pattern. The aorta at the anastomosis, is initially smaller than normal (z-score -0.64). After 4 months the z-score is 0.83, followed by continued growth of 0.1 z-score per year. At the last visit, the aortic valve z-score was above 2 in 51 patients, between -2 and 2 in 72 and less than -2 in six patients, none of whom had a flow velocity above 2 m/s. z-score of patients with VSD remained above those without VSD (P<0.0001). Aortic insufficiency was grade 2/4 in three patients, grade 3/4 in one and grade 4/4 in one. No patient developed aortic stenosis. CONCLUSION: After ASO the neo-aortic valve and sinus are larger than normal, representing the natural size difference in the prenatal situation and influence of associated cardiac malformations. In the first year of life, rapid dilatation of the new aorta is observed, followed by growth towards normalization of the valve and sinus size. Stenosis at the anastomosis was not observed. Aortic dilatation by itself is rarely associated with significant insufficiency.

[Arterial-switch operation for transposition of the great vessels; good results in the Wilhelmina Children's Hospital, Utrecht, 1977-2000]. / Arteriële-switchoperatie bij transpositie van de grote vaten; gunstige resultaten in het Wilhelmina Kinderziekenhuis Utrecht, 1977-2000.

OBJECTIVE: To examine the results of the arterial switch operation which is used to correct the transposition of the great arteries. DESIGN: Descriptive. METHOD: In the period May 1977-October 2000 195 patients at the Wilhelmina Children's Hospital in Utrecht, the Netherlands, underwent an arterial switch operation. The patient group consisted of 132 boys and 63 girls, with a median age at surgery of 8 days (range: 0-1976). In accordance with the protocol, the postoperative follow-up consisted of echocardiography and an ECG. Further investigations were performed on indication. Additional data were collected from the status reports. The mean follow-up was 8.0 years (range: 0.04-22.17). RESULTS: The overall peri-operative mortality was 15% (30/195). Initially this figure was about 50%, in the 1980s it was 15% and from 1996 onwards it was 4%. Of the 151 surviving and traceable patients, 2 patients died years later (1.3%). Of the remaining 149 patients, 145 were classified in New York Heart Association class I and 4 in class II. Due to pulmonary stenosis, 45 reinterventions were required in 26 patients (/149; 17%). Left ventricle dysfunction occurred in 5 patients (3%), arrhythmias in 5 patients and aorta abnormalities in 5 patients. Coronary artery abnormalities were found in 5 of the 61 patients who underwent angiography (8%). CONCLUSION: Peri-operative mortality decreased to 4% and late mortality was 1.3%. The long-term clinical outcome of the arterial switch operation was good. Morbidity was predominantly caused by pulmonary stenosis and late coronary obstruction.

[Balloon angioplasty as the primary treatment for coarctation of the aorta in 30 children; immediate results and follow-up]. / Ballonangioplastiek als primaire behandeling van coarctatio aortae bij 30 kinderen; directe resultaten en follow-up.

OBJECTIVE: Evaluation of the results of balloon dilatation in coarctation of the aorta in children. DESIGN: Retrospective. METHOD: In the years 1990-1999 30 patients with a congenital coarctation of the aorta were treated with balloon angioplasty in the Children's Heart Centre of Utrecht University Medical Centre, the Netherlands. The group comprised 5 girls and 25 boys, with a mean age of 4.8 years (range 1 month-16 years) without severe associated congenital heart defects or a long segment coarctation. Follow-up included Doppler echocardiography and MRI within the first 6 years after the procedure. The fall of the pressure gradient was assessed with Student's t-test for paired observations and the reintervention period was calculated by the Kaplan-Meier method. RESULTS: No children died. Of 30 procedures performed, 28 (93%) were considered successful. Mean pressure gradient was reduced from 36.2 mmHg (SD: 12.7) to 13.1 mmHg (SD: 9.3) (p < 0.001). Mean follow-up was 4.1 years; the follow-up of 11 patients was longer than 5 years. Four patients (13%) developed a recoarctation. No aneurysm formation was encountered (n = 14). CONCLUSION: Balloon angioplasty for the treatment of native coarctation of the aorta in children may be an efficient and not very damaging solution for this selected group of patients.

Influence of coronary anatomy and reimplantation on the long-term outcome of the arterial switch.

BACKGROUND: Abnormal coronary artery anatomy is reported to have a significant influence on the outcome of the arterial switch operation. This study examines the impact of coronary anatomy and the occurrence of late coronary obstruction on left ventricular (LV) function and long-term outcome. METHODS: Coronary artery anatomy, of 170 patients after arterial switch operation (1977-1999), was determined based on operative reports and pre-operative aortograms. Current status was evaluated using ECGs, echocardiograms, scintigraphy, and post-operative coronary angiograms. RESULTS: In 133/170 patients, coronary artery anatomy consisted of an anterior descending (LAD) and circumflex artery (Cx) from the left sinus and the right coronary artery (RCA) from the right or posterior sinus. The left coronary had an intramural initial course in two of these patients. Fifteen patients had the LAD from the left and Cx and RCA from the right sinus; eight had LAD and RCA from one sinus and Cx from the other; four had single ostium; and three had three separate ostia. Four patients had complex patterns and four patients had a supra commissural coronary. To date, follow-up angiography was performed in 59 patients. Surgical coronary sequellae were found in five patients. Two patients had an occluded left ostium. Initially, they were asymptomatic but showed polymorphic ventricular extrasystoles on ECG and moderate LV dysfunction with large irreversible perfusion defects on scintigraphy. Both patients developed ventricular fibrillation at the age of 14 years. One patient did not survive. The other patient required implantation of a defibrillator. One patient has an occluded RCA, one patient has stenosis of the right ostium and one patient has multiple tortuous collaterals without obstruction of a major branch. In the latter three patients, coronary sequellae were not suspected on ECG, echo, or scintigraphy and were only found on follow-up angiography. Retrograde collateral flow was noted in all three occluded coronaries. LV dysfunction, with normal coronaries, was noted in three patients. All, of these patients, had peri-operative ischaemia suggesting failure of myocardial protection. Two are now asymptomatic with mild LV dysfunction. One patient continues to have severe myocardial dysfunction and secondary aortic insufficiency. A Ross-like procedure was performed placing the original aortic valve in the neo-aortic root. Coronary artery anatomy did not influence early survival or late coronary sequellae. CONCLUSION: Abnormal coronary anatomy was not a determinant of outcome in our study. Surgical coronary obstruction is independent of original anatomy. It can be almost silent and is potentially fatal. Follow-up angiography must be considered in all patients after the arterial switch operation.

Air travel and adults with cyanotic congenital heart disease.

BACKGROUND: Concern has been expressed that a reduction of partial oxygen pressure during flight in commercial aircraft may induce dangerous hypoxemia in patients with cyanotic congenital heart disease. METHODS AND RESULTS: To evaluate the validity of this concern, the transcutaneous SaO2 was measured in 12 adults with this type of heart disease and 27 control subjects during simulated commercial flights of 1.5 and 7 hours in a hypobaric chamber. Ten of those patients and 6 control subjects also were evaluated during two actual flights of approximately 2.5 hours in a DC-10 and an A-310, respectively. During the prolonged simulated and actual flights, the capillary blood pH, gases, and lactic acid were analyzed in the patients and during one of the actual flights also in the control subjects. During the simulated flights the SaO2 was at all times lower in the patients than in the control subjects. However, the maximal mean actual percentage decrease, as compared with sea level values, did not exceed 8.8% in either patients or control subjects. During the actual flights, this maximal decrease in the patients was 6%. In-flight reduction of the capillary PO2 was considerable in the control subjects but not in the patients. It is our hypothesis that the lack of a significant decrease of the PO2 in the patients might possibly be due to a high concentration of 2.3 diphosphoglycerate in the red cells. The flights had no influence on the capillary blood pH, PCO2, bicarbonate, or lactic acid levels in either patients or control subjects. CONCLUSIONS: Atmospheric pressure changes during commercial air travel do not appear to be detrimental to patients with cyanotic congenital heart disease.

Late re-interventions following arterial switch operations in transposition of the great arteries. Incidence and surgical treatment of postoperative pulmonary stenosis.

Seventy-six patients were studied after arterial switch operation (ASO) between May 1977 and February 1992. Pulmonary artery reconstruction was initially performed by: conduit interposition in 5 patients, direct main pulmonary artery anastomosis and button patches in 60 patients, and pantaloon-like patch repair in 11 patients. Pulmonary stenosis developed in 17 patients (22%), requiring a total of 26 late re-interventions. Re-intervention was required in four out of five patients operated with pulmonary artery conduits, 11 out of 60 with a button patch repair and 2 out of 11 following pantaloon-type repair. In this series pulmonary artery stenosis (PS) involving the pulmonary valve occurred in 9/17 patients. Involvement of the pulmonary valve was related to the technique of pulmonary artery reconstruction. In these patients surgery is necessary. Balloon angioplasty can be a valuable tool when the stenosis is more distal. The incidence of PS was not influenced by the type of reconstruction or the use of Lecompte's maneuver.