Rare coronary artery variants are associated with increased mortality and reinterventions following the arterial switch operation

OBJECTIVE

To determine the influence of coronary anatomy on long-term outcomes of the arterial switch operation (ASO).

METHODS

We retrospectively reviewed patients with transposition of the great arteries or Taussig-Bing anomaly who underwent ASO at our institution between 1992 and 2022. The primary endpoint was freedom from a composite of death, transplantation, and coronary reintervention.

RESULTS

A total of 632 patients (median age, 5.0 days; interquartile range [IQR], 4.0-7.0 days) underwent ASO. Coronary anatomy included the following categories: usual (n = 411; 65%), circumflex (Cx) from sinus 2 (n = 89; 14%), inverted (n = 55; 9%), single sinus (n = 46; 7%), and intramural (n = 31; 5%). Overall operative mortality was 3% (n = 16) and highest in patients with intramural cardiac anatomy (n = 3; 10%), although it dropped to 0% in this group in the most recent decade. The median duration of follow-up was 14.5 years (IQR, 6.0-20.3 years). Twenty-year freedom from the primary endpoint was 95 ± 1% for usual anatomy, 99 ± 1% for Cx from sinus 2, 90 ± 4% for inverted, 91 ± 4% for single sinus, and 80 ± 9% for intramural (P < .001). Intramurals had the highest 20-year incidence of coronary reintervention (11 ± 8%). Cox modeling identified intraoperative coronary revision (hazard ratio [HR], 20.1; 95% confidence interval [CI], 9.4-53.9; P < .001), Taussig-Bing anomaly (HR, 4.9; 95% CI, 2.2-10.9; P < .001), and an intramural coronary artery (HR, 2.9; 95% CI, 1.0-8.2; P = .04) to be risk factors for the composite endpoint.

CONCLUSIONS

Rare coronary artery variants-particularly intramural-are associated with increased mortality and coronary reinterventions after ASO. A low threshold for unroofing intramurals is likely associated with declining mortality and improved outcomes. Additional investigations are needed to determine the long-term fate of the coronary arteries after ASO.

The Arterial Switch Operation in the Developing World: Risk Factors and Current Outcomes

BACKGROUND

Published data on the outcomes of the arterial switch operation in the developing world are limited. We sought to identify the midterm outcomes of and risk factors for mortality and morbidity in patients undergoing the arterial switch operation at a high-volume center in Vietnam.

METHODS

A retrospective review was conducted of 608 patients who underwent an arterial switch operation for the treatment of transposition of the great arteries (TGA; n = 509) or double-outlet right ventricle TGA (DORV-TGA; n = 99) at a single center from 2010 to 2021.

RESULTS

Overall early mortality was 5.9%, and late mortality was 1%. Multivariate Cox regression showed weight at operation of <3 kg (P < .001), prolonged aortic cross-clamp time (P < .001), and need for secondary aortic cross-clamp (P = .011) as risk factors for overall mortality. The actuarial 10-year survival rate was 93%. The overall cardiac reoperation rate was significantly higher in patients with DORV-TGA (hazard ratio [HR], 16.43; 95% CI, 4.70-57.43; P < .001). The rate of freedom from cardiac reoperation at 10 years was 94%. Risk factors for outflow tract reoperation were patients with DORV-TGA (HR, 23.28; 95% CI, 2.86-189.66; P = .003), single coronary artery (HR, 4.1; 95% CI, 1.16-14.46; P = .028), and mild aortic valve regurgitation observed in 3.7% of patients.

CONCLUSIONS

The outcomes of the arterial switch operation in a low- and middle-income country were satisfactory. Nevertheless, the complexity of the procedure and lower weight of patients are still challenges. Patients with DORV-TGA and single coronary artery need to be closely followed up.

Techniques and pitfalls of coronary arterial reimplantation in anatomical correction of transposition

BACKGROUND AND AIM

We assessed the anatomical variations in coronary arterial patterns relative to the techniques of reimplantation in the setting of the arterial switch operation, relating the variations to influences on outcomes.

METHODS

We reviewed pertinent published investigations, assessing events reported following varied surgical techniques for reimplantation of the coronary arteries in the setting of the arterial switch procedure.

RESULTS

The prevalence of reported adverse events, subsequent to reimplantation, varied from 2% to 11%, with a bimodal presentation of high early and low late incidence. The intramural pattern continues to contribute to mortality, with some reports of 28% fatality. The presence of abnormal course relative to the arterial pedicles in the setting of single sinus origin was associated with a three-fold increase in mortality. Abnormal looping with bisinusal origin of arteries was not associated with increased risk.

CONCLUSION

The techniques of transfer of the coronary arteries can be individually adapted to cater for the anatomical variations. Cardiac surgeons, therefore, need to be familiar with the myriad creative options available to achieve successful repair when there is challenging anatomy. Long-term follow-up will be required to affirm the superiority of any specific individual technique. Detailed multiplanar computed-tomographic scanning can now reveal all the variants, and elucidate the mechanisms of late complications. Coronary angioplasty or surgical revascularization may be considered in selected cases subsequent to the switch procedure.

Impact of Coronary Artery Anatomy in Arterial Switch Operation: In-hospital and Post-discharge Outcomes

OBJECTIVE

The influence of the coronary artery anatomy on the prognosis of patients receiving an arterial switch operation (ASO) is currently controversial, and the risk factors for this operation may change in more complicated patients. This study aimed to investigate the influence of coronary artery anomalies on the in-hospital and post-discharge outcomes of ASO in patients with transposition of the great arteries (TGA) and Taussig-Bing anomaly (TBA).

METHODS

We retrospectively reviewed 206 patients who underwent ASO from January 2007 to December 2019. The median age at operation was 33 [interquartile range (IQR): 20-71] days. Median follow-up time was 7.2 years (IQR: 4.0-10.3 years).

RESULTS

Coronary anomalies were present in 86 patients (41.7%), with 9 (4.4%) of them having a single coronary artery. Additional coronary features included intramural courses in 5 (2.4%) patients, ostial stenosis in 1 (0.5%) patient, and accessory coronary artery orifices in 5 (2.4%) patients. There were 32 (15.5%) in-hospital deaths and 8 (4.6%) post-discharge deaths, yielding an overall survival of 81.3%, 80.7% and 79.9% at 1, 5 and 10 years, respectively. Mortality due to ASO has been drastically decreased since 2013. Patients with a single coronary artery had higher rate of in-hospital mortality, but this finding was not statistically significant. The earlier surgical era (OR: 2.756) and a longer cardiopulmonary bypass time (OR: 2.336) were significantly associated with in-hospital mortality, while coronary patterns were not. An intramural coronary artery (HR: 10.034) and a patient age of older than 1 year at the time of ASO (HR: 9.706) were independent predictors of post-discharge mortality.

CONCLUSION

ASO remains the procedure of choice for TGA with coronary anomalies with acceptable in-hospital and post-discharge outcomes in terms of overall survival and freedom of reoperation. However, intramural coronary artery is an independent risk factor for post-discharge mortality. Timely surgery within the 1st year of life helps improve overall midterm survival of ASO.

The Coronary Arteries in Adults after the Arterial Switch Operation: A Systematic Review

Coronary artery status in adults long after the arterial switch operation (ASO) is unclear. We conducted a systematic review to provide an overview of coronary complications during adulthood and to evaluate the value of routine coronary imaging in adults after ASO, in light of current guidelines. Articles were screened for the inclusion of adult ASO patients and data on coronary complications and findings of coronary imaging were collected. A total of 993 adults were followed with a median available follow-up of only 2.0 years after reaching adulthood. Myocardial ischemia was suspected in 17/192 patients (8.9%). The number of coronary interventions was four (0.4%), and coronary death was reported in four (0.4%) patients. A lack of ischemia-related symptoms cannot be excluded because innervation studies indicated deficient cardiac innervation after ASO, although data is limited. Anatomical high-risk features found by routine coronary computed tomography (cCT) included stenosis (4%), acute angle (40%), kinking (24%) and inter-arterial course (11%). No coronary complications were reported during pregnancy (n = 45), although, remarkably, four (9%) patients developed heart failure. The 2020 European Society of Cardiology (ESC) guidelines state that routine screening for coronary pathologies is questionable. Based on current findings and in line with the 2018 American ACC/AHA guidelines a baseline assessment of the coronary arteries in all ASO adults seems justifiable. Thereafter, an individualized coronary follow-up strategy is advisable at least until significant duration of follow-up is available.

Arterial switch operation for transposition of the great arteries: A single-centre 32-year experience

OBJECTIVE

Arterial switch operation (ASO) is nowadays the standard of care for neonates with D-transposition of the great arteries (D-TGA). We evaluated our early and late results with ASO for D-TGA.

MATERIALS AND METHODS

We collected data on 267 patients with D-TGA, either with intact ventricular septum (D-TGA/IVS; n = 182, 68%) and with other associated congenital heart malformations (complex D-TGA; n = 85, 32%) that underwent ASO between January 1987 and July 2018.

RESULTS

Median age at ASO was 8 days (interquartile range [IQR], 6-12 days). Fifteen patients (5.6%) died in hospital (6/182 with D-TGA/IVS, 3.3% and 9/85 with complex D-TGA, 11%; P = 0.02). Median follow-up time was 10.2 years (IQR, 3.7-18 years). There were 2 (0.8%) late sudden deaths. Overall survival at 10 and 20 years was 94% and 93%, respectively. Thirty-five patients (14%) required either reoperations or reinterventions, mainly for right ventricular outflow tract obstruction (n = 28, 11%). Freedom from reoperation/reintervention at 10 and 20 years was 87% and 78%, respectively. All patients were in NYHA I at latest clinical examination. Six over 173 patients (3.4%) who underwent a postoperative evaluation of their coronaries presented acquired anomalies. Forty-four patients (17%) who performed a cardiopulmonary exercise testing (CPET) have a predicted VO ₂ comparable to normal peers.

CONCLUSIONS

The results of ASO for D-TGA are excellent, with a fairly low mortality and reoperation/reintervention rate. Functional capacity evaluated with CPET is comparable to normal peers. Continuous follow-up for detecting asymptomatic acquired coronary artery disease is mandatory. A reassessment of competitive sport eligibility criteria for specific D-TGA patients should be considered.

Long-term Management of the Arterial Switch Patient

PURPOSE OF REVIEW

This review paper describes the management of patients with dextro-transposition of the great arteries (D-TGA) with a focus on the complications seen and the appropriate care required to identify and prevent adverse events.

RECENT FINDINGS

D-TGA is a form of cyanotic congenital heart disease (CHD) representing ~ 3% of all CHD and almost 20% of all cyanotic CHD. Since the late 1980s, standard of care is to repair these patients with an arterial switch operation (ASO) as opposed to a Mustard/Senning operation. The long-term survival and complication rates are superior in the ASO. Long-term follow-up is recommended for all D-TGA patients and includes management with adult congenital heart disease specialists and the use of echocardiography and advanced imaging with CT or MRI. The most common complications seen are pulmonary stenosis, coronary artery stenosis, and neo-aortic regurgitation. Careful evaluation of new symptoms or declining function is essential in preventing and treating these long-term sequelae.

Successful Late Recruitment of the Occluded Left Main Coronary Artery After Initial Arterial Switch Operation

We describe a surgical technique for late recruitment of the proximally occluded left main coronary artery (LMCA) after initial arterial switch operation, which had been complicated by severe left ventricular dysfunction. This technique allowed for LMCA recanalization, using the patent conal artery branching off the LMCA close to the ostium. It is particularly useful in small children, where surgical options for coronary arteries are limited and associated with a high risk of restenosis. It was successfully used in a two-month-old boy with successful revascularization confirmed by angiography.