Asian Cardiovasc Thorac Ann 2004;12:38-40
© 2004 Asia Publishing EXchange Ltd
Arterial Switch Operation without Coronary Translocation: Mid-term Results
Kona Samba Murthy, MCh,
Robert Coelho, MCh,
Snehal Kulkarni, MD1,
Benjamin Ninan, MD2,
Kotturathu Mammen Cherian, FRACS
Department of Cardiac Surgery
1 Department of Cardiology
2 Department of Anesthesiology, Institute of Cardiovascular Diseases, Chennai, India
For reprint information contact: Kona Samba Murthy, MCh Tel: 91 40 2360 0852 Fax: 91 40 2360 8050 Email: konasmurthy{at}hotmail.com Apollo Children’ Heart Hospital, Jubilee Hills, Hyderabad AP 500 033, India.
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ABSTRACT
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We innovated a technique of arterial switch operation without coronary translocation in 1995, which avoids problems related to coronary artery translocation with good mid-term results. It is a better alternative for surgeons who are not well versed with coronary translocation of conventional arterial switch operation and with difficult coronary anatomy. This report deals with the mid-term results of our new technique.
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INTRODUCTION
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A multi-institutional study showed that units performing fewer than 20 arterial switch operations (ASO) a year have higher mortality compared to busy units.1 Coronary artery translocation is the most important step for achieving successful outcome in conventional ASO, which requires high technical expertise. We innovated a new technique of ASO without coronary translocation in 19952 and report the mid-term results of our technique.
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MATERIALS AND METHODS
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From September 1995 to August 1998, 41 cases of transposition of great arteries (TGA) and its variants were operated upon with our new technique. The clinical spectrum included TGA, intact ventricular septum (IVS) – 14 cases (34%) and TGA, ventricular septal defect (VSD), including Taussig Bing anomaly – 27 cases (66%). The age ranged from 13 days to 2.5 years (median, 6 months) and weight ranged from 2 to 11.5 kg (median, 4.1 kg). The coronary artery pattern observed was as per Table 1
. The admission pattern for ASO is given in Table 2.
After median sternotomy and routine cardiopulmonary bypass (CPB), the ductus was ligated and divided. The patient was cooled to 20–24°C and under cardioplegic arrest the great arteries were transected just above commissures. A hockey-stick-shaped incision was made in the proximal aorta and pulmonary artery on facing sinuses. The flaps were sutured in such a way that coronary ostia were committed to neoaorta. After Lecompte maneuver the distal aorta was anastomosed to neoaorta. Neo-pulmonary artery was enlarged anteriorly with a pericardial patch and anastomosed to distal pulmonary artery (PA). The detailed description of the technique was published earlier.2
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RESULTS
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The CPB time ranged from 120 to 402 min (mean, 184 min); aortic crossclamp time ranged from 41 to 141 min (mean, 73 min) and total circulatory arrest time ranged from 4 to 36 min (mean, 16 min).
Overall, the hospital mortality was 22% (9/41): 14% (2/14) in TGA IVS group and 26% (7/27) in TGA VSD, including Taussig Bing Group. Four patients died of persistent pulmonary artery hypertensive crisis, 4 patients died of low cardiac output and multiorgan failure, and 1 patient died of acute cardiac failure following right ventricular outflow tract (RVOT) obstruction. The period of ventilation ranged from 1 to 21 days (mean, 6 days). Delayed sternal closure was done in 7 patients (16%).
All surviving 32 patients were followed-up from 28 to 64 months. One patient who did not have RVOT patch enlargement in the initial surgery required relief of RVOT obstruction 2 years after the primary correction. No other patient had significant RVOT or left ventricular outflow tract (LVOT) obstruction or semilunar valve incompetence. All patients underwent echocardiogram at regular intervals during follow-up. Cardiac catheterization and angiocardiography were done in 8 patients, which showed good growth of neoaorta, new PA and coronary arteries without any obstructions (Figure 1). Dobutamine stress thallium and MUGA were performed in the 8 patients, which showed no myocardial perfusion defects and regional wall motion abnormalities (Figure 2). There was no late death. All surviving patients were in Class I, without any cardiac medication.
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Figure 2. Rest and stress thallium scan showing good myocardial perfusion without any filling defects (2 years after surgery)
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DISCUSSION
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A multi-institutional study showed units that perform fewer than 20 ASOs per year have mortality of 36–55% (with 29–33% confidence limits) compared to busy units. The pattern of admissions in our hospital for ASO is given in Table 2
, which shows an average of 13.6 patients per year. The median age of these patients was 6 months. The multi-institutional study showed that a mean age of more than 14 days carries higher mortality. Generally, about 30% of the TGA are associated with large or small VSD, but in our series 66% patients were associated with VSD1,3 which indicates that these patients survived a longer period because of the good intermixing of blood. Many reports showed TGA associated with VSD had higher mortality when compared to those with intact ventricular septum. But all these patients who had VSD developed severe pulmonary artery hypertension before surgery, which poses a higher risk for surgery.
The multi-institutional study showed that the reasons for the failure of over half of the institutions to achieve survival rates as high as those obtained in the low-risk institutions were not evident. The study suggested that the difference might be in the difficulty of defining qualitative aspects of the repair and the intraoperative and early postoperative care. Lack of improvement in survival rates across 2 years of the study in both groups of institutions indicates that improvements do not result from experience alone.1 This explains the reason for high mortality was fewer cases rather than the surgical technique per se.
Coronary artery translocation is the most important step to achieve a successful outcome in conventional ASO in transposition of great arteries. Yacoub, 4 Planche5 and various other surgeons described a variety of techniques for various coronary artery patterns. Different coronary artery patterns, one of the important risk factors, require appropriate techniques to translate the coronary artery to the neoaorta. There should not be any traction or kinking during the translocation.
In conventional techniques, the risk of death is increased when the left main coronary artery or either of its branches arises from sinus 2, single coronary artery and intramural course.6,7 It requires dissection and mobilization of proximal coronary arteries, which might lead to fibrosis and scarring leading to stenosis.8 In our experience, more than half (53%) of the patients had unusual (high risk) coronary artery pattern. With our technique, whatever the coronary artery pattern may be, the same technique of coronary reallocation is used. Since it is not mobilized from the original course of the coronary artery, there is no risk of coronary kinking and traction. The high-risk coronary pattern for conventional techniques is nullified with this new technique. Since there is no need for dissection in the proximal course of the coronary arteries, the incidence of fibrosis, scarring and stenosis are not seen in mid-term.
In the follow-up, echocardiogram, cardiac catheterization and angiocardiogram showed good growth of neoaorta and neo-pulmonary artery without significant LVOT or RVOT obstructions. No patient developed coronary artery stenosis.
In our experience, an older age group (median 6 months), higher incidence of VSD (66%) with severe PAH and fewer number of cases accrues to the higher mortality. Other factors contributing to high mortality were delayed referral, malnutrition, difference between chronological age and biological age and suboptimal infrastructure. These are the usual problems in developing countries.
We thank Mrs Revathy Vijay Kumar, Secretary, and Mr Pary Uma, Medical Illustrator, for their help in preparing this manuscript.
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REFERENCES
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- Norwood WI, Dobell AR, Freed MD, Kirklin JW, Blackstone EH. Intermediate results of the arterial switch repair, a 20-institution study. J Thoracic Cardiovasc Surg
1988;96:854–63.[Abstract]
- Murthy KS, Cherian KM. A new technique of arterial switch operation with in situ coronary reallocation for transposition of great arteries. J Thoracic Cardiovasc Surg
1996;112:27–32.[Abstract/Free Full Text]
- Kirklin JW, Barratt-Boyes BG. Complete transposition of the great arteries. In: Kirklin JW, Barratt-Boyes BG. eds. Cardiac Surgery: Morphology, Diagnostic Criteria, Natural History, Techniques, Results, and Indications. 2nd ed. New York, Churchill Livingstone 1993:1384–467.
- Yacoub MH, Radley-Smith R. Anatomy of the coronary arteries in transposition of the great arteries and methods for their transfer in anatomical correction. Thorax
1978;33:418–24.[Abstract/Free Full Text]
- Planche C, Bruniaux J, Lacour-Gayet F, Kachaner J, Binet JP, Sidi D, et al. Switch operation for transposition of the great arteries in neonates. A study of 120 patients. J Thorac Cardiovasc Surg
1988;96:354–63.[Abstract]
- Mayer JE Jr, Sanders SP, Jonas RA, Castaneda AR, Wenovsky G. Coronary artery pattern and outcome of arterial switch operation for transposition of the great arteries. Circulation
1990:82(suppl IV):139–45.
- Kirklin JW, Blackstone EH, Tchervenkov CI, Castaneda AR. Clinical outcomes after the arterial switch operation for transposition. Patient support, procedural, and institutional risk factors. Circulation
1992;86:1501–15.[Abstract/Free Full Text]
- Daebritz SH, Nollert G, Sachweh JS, Engelhardt W, von Bernuth G, Messmer BJ. Anatomical risk factors for mortality and cardiac morbidity after arterial switch operation. Ann Thorac Surg
2000; 69:1880–6.[Abstract/Free Full Text]
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ABSTRACT
INTRODUCTION
