Neoaortic Regurgitation Detected by Echocardiography After Arterial Switch Operation: A Systematic Review and Meta-Analysis

Background

Neoaortic root dilatation (NeoARD) and neoaortic regurgitation (NeoAR) are common sequelae following the arterial switch operation (ASO) for transposition of the great arteries.

Objectives

The authors aimed to estimate the cumulative incidence of NeoAR, assess whether larger neoaortic root dimensions were associated with NeoAR, and evaluate factors associated with the development of NeoAR during long-term follow-up.

Methods

Electronic databases were systematically searched for articles that assessed NeoAR and NeoARD after ASO, published before November 2022. The primary outcome was NeoAR, classified based on severity categories (trace, mild, moderate, and severe). Cumulative incidence was estimated from Kaplan-Meier curves, neoaortic root dimensions using Z-scores, and risk factors were evaluated using random-effects meta-analysis.

Results

Thirty publications, comprising a total of 6,169 patients, were included in this review. Pooled estimated cumulative incidence of ≥mild NeoAR and ≥moderate NeoAR at 30-year follow-up were 67.5% and 21.4%, respectively. At last follow-up, neoaortic Z-scores were larger at the annulus (mean difference [MD]: 1.17, 95% CI: 0.52-1.82, P < 0.001; MD: 1.38, 95% CI: 0.46-2.30, P = 0.003) and root (MD: 1.83, 95% CI: 1.16-2.49, P < 0.001; MD: 1.84, 95% CI: 1.07-2.60, P < 0.001) in patients with ≥mild and ≥moderate NeoAR, respectively, compared to those without NeoAR. Risk factors for the development of any NeoAR included prior pulmonary artery banding, presence of a ventricular septal defect, aorto-pulmonary mismatch, a bicuspid pulmonary valve, and NeoAR at discharge.

Conclusions

The risks of NeoARD and NeoAR increase over time following ASO surgery. Identified risk factors for NeoAR may alert the clinician that closer follow-up is needed. (Risk factors for neoaortic valve regurgitation after arterial switch operation: a meta-analysis; CRD42022373214).

Anatomical reconstruction of proximal coronary artery stenosis in children

OBJECTIVES

Timing and method of surgical reconstruction for non-sclerotic proximal coronary artery stenosis, occuring de-novo or post coronary artery transfer, are evolving. We have pursued a technique of anatomical reconstruction of ostial and short segment proximal coronary artery stenosis and atresia in children, using patch plasty or interposition vein graft. Herein, we discuss the medium- to long-term outcome.

METHODS

Nine consecutive children undergoing ten left main coronary artery reconstructions using autologous great saphenous vein patch (n = 4), autologous pericardium (n = 4), xenopericardium (n = 1) or great saphenous vein interposition graft (n = 1) were retrospectively analysed. Complementary wedge resection of the stenotic coronary ostium was performed in chronic cases.

RESULTS

The aetiology of coronary artery stenosis was post arterial switch operation (n = 6), Takayasu`s arteritis (n = 1), idiopathic left main coronary artery atresia (n = 1) and anomalous origin of the left coronary artery from the pulmonary artery (n = 1). Median age and weight at operation were 0.15 (range 0.01-13.1) years and 4.4 (range 3 -13.1) kilograms, respectively. Survival was 100% at median follow-up of 12.6 (range 1-19.2) years. All patients showed normal left ventricular ejection fraction on transthoracic echocardiogram. In one patient, kinking of the proximal left circumflex artery resulted in non-significant obstruction. In all other cases, follow-up catheter angiography revealed unobstructed coronary arteries. Cardiac magnetic resonance tomography showed no significant perfusion deficit in any child.

CONCLUSIONS

Anatomical reconstruction of the proximal left coronary artery using autologous saphenous vein may allow optimal restoration of physiological coronary blood flow, keeping the option of future coronary bypass operation open.

Early Outcomes of Patients Undergoing Neoaortic Valve Repair Incorporating Geometric Ring Annuloplasty

OBJECTIVES

During congenital heart surgery, the pulmonary valve and root may be placed into the systemic position, yielding a "neoaortic" valve. With the stress of systemic pressure, the pulmonary roots can dilate, creating aneurysms and/or neoaortic insufficiency (neoAI). This report analyzes the early outcomes of patients undergoing neoaortic valve repair incorporating geometric ring annuloplasty.

METHODS

Twenty-one patients underwent intended repair at six centers and formed the study cohort. Thirteen had previous Ross procedures, five had arterial switch operations, and three Fontan physiology. Average age was 21.7 ± 12.8 years (mean  ±  SD), 80% were male, and 11 (55%) had symptomatic heart failure. Preoperative neoAI Grade was 3.1  ±  1.1, and annular diameter was 30.7  ±  6.5 mm.

RESULTS

Valve repair was accomplished in 20/21, using geometric annuloplasty rings and leaflet plication (n = 13) and/or nodular release (n = 7). Fourteen had neoaortic aneurysm replacement (13 with root remodeling). Two underwent bicuspid valve repair. Six had pulmonary conduit changes, one insertion of an artificial Nodulus Arantius, and one resection of a subaortic membrane. Ring size averaged 21.9  ±  2.3 mm, and aortic clamp time was 171  ±  54 minutes. No operative mortality or major morbidity occurred, and postoperative hospitalization was 4.3  ±  1.4 days. At discharge, neoAI grade was 0.2  ±  0.4 (P < .0001), and valve mean gradient was ≤20 mm Hg. At average 18.0  ±  9.1 months of follow-up, all patients were asymptomatic with stable valve function.

CONCLUSIONS

Neoaortic aneurysms and neoAI are occasionally seen late following Ross, arterial switch, or Fontan procedures. Neoaortic valve repair using geometric ring annuloplasty, leaflet reconstruction, and root remodeling provides a patient-specific approach with favorable early outcomes.

Neo-aortic posterior sinus of Valsalva reduction and closed coronary artery transfer as a method to approach aortopulmonary mismatch in transposition of great arteries

OBJECTIVE

In transposition of great arteries (TGA), aortopulmonary mismatch (APM) can determine postoperative neo-aortic insufficiency after arterial switch operation (ASO). The distortion of sinu-tubular junction may be the geometric mechanism responsible. We developed a strategy able to reduce the mismatch at the timing of ASO, and in this study, we aimed to describe our indications and results.

METHODS

Preoperative root circumferences at the level of the mid-portion of sinus of Valsalva and ascending aorta circumference were used to define APM. Indication to surgery was a neo-aortic root (NAR) to ascending aorta ratio ≥ 1.4. Along with standard ASO, posterior neo-aortic sinus inverted conal resection and punch technique for coronary reimplantation was used in all patients to re-establish the more geometric ratio possible between the two components. Hypoplastic aortic arch (HAA) and aortic coarctation (CA) were managed by aortic arch enlargement with an autologous pericardial patch.

RESULTS

Twenty patients (20 male), 19 with diagnoses TGA (17 with ventricular septal defect, 85%) and 1 with Taussig-Bing anomaly underwent ASO. HAA was present in three (15%) and CA in two (10%). The mean preoperative neo-aortic to ascending aorta ratio was 1.8 versus 1.1 postoperatively (p < .01). No moderate or severe neo-aortic insufficiency was observed before discharge and at a mean follow-up of 4.3 years (interquartile range = 0.5-12 years).

CONCLUSION

Neo-aortic reduction plasty with coronary reimplantation by punch technique is an effective strategy to approach preoperative APM in TGA. This technique confers a more harmonious geometry to NAR that can improve neo-aortic valve function.

Growth Pattern of the Neo-Aorta after Arterial Switch Operation during Childhood

Background and Objectives

Neo-aortic root dilatation (ARD) and annular dilatation (AAD) tend to develop after arterial switch operation (ASO). However, the trend of neo-aortic growth has not been well established. This paper aims to identify this trend, its associated factors, and predictors of neo-aortic dilatation after ASO.

Methods

We analyzed the growth trend of the neo-aortic root, annulus, and sinotubular junction (STJ) z-scores using random coefficients model and the risk factors affecting neo-aortic dilatation in 163 patients who underwent ASO from 2006 to 2015.

Results

Among 163 patients, 41 had a ventricular septal defect, and 11 had Taussig-Bing (TB) anomaly. The median follow-up duration was 6.61 years. The increased in the neo-aortic root z-score was different between the trapdoor and non-trapdoor coronary artery transfer techniques (0.149/year, p<0.001 vs. 0.311/year, p<0.001). Moreover, the neo-aortic annulus and STJ z-score significantly increased over time after ASO (0.067/year, p<0.001; 0.309/year, p<0.001). Pulmonary artery banding (PAB) was rather a negative affecting factor. The probabilities of freedom from ARD, AAD, and neo-aortic STJ dilatation at 10 years after ASO were 33.4%, 53.9%, and 65.4%. Neo- aortic regurgitation within 1 year was the predictor of ARD, AAD, and neo-aortic STJ dilatation. TB anomaly, PAB, and native pulmonary sinus z-score were other predictors for ARD.

Conclusion

The growth of neo-aortic root, annulus, and STJ after ASO was greater than somatic growth during childhood. The coronary artery transfer technique affected the growth pattern of the neo-aortic root.

Does Coronary Reimplantation After Neoaortic Reconstruction Increase Aortic Regurgitation?

Coronary reimplantation after neoaortic reconstruction (CRANR) in the arterial switch operation (ASO) allows easy selection of accurate coronary transfer sites in the distended neoaorta. However, neoaortic valve injury may occur during coronary reimplantation. We determined whether the CRANR procedure increased the incidence of aortic valve regurgitation (AR) after ASO. Between March 1994 and August 2017, 227 patients underwent ASO. Since September 2000 CRANR has been performed on 155 patients and open coronary reimplantation (OCR) on 72. Patients who had undergone aortocoronary flaps procedures (n = 13), had early or late mortality (n = 27), or lacked data (n = 11) were excluded. We enrolled and retrospectively reviewed the medical records of 176 patients who were followed up for postoperative AR: 38 underwent OCR and 138 underwent CRANR. We compared the incidences of early and late postoperative AR in both groups. We defined mild or greater AR as "significant AR." The groups did not differ in body weight at operation, great artery relationship, and coronary artery anatomy. The incidences of significant AR at discharge were 21.1% (8/38) in the OCR group and 16.6% (23/138) in the CRANR group (p = 0.53). The freedom from significant AR at 5 years was 59.9% in the OCR group and 62.4% in the CRANR group with no difference between the two groups (p = 0.73). Moderate AR occurred in one patient in the CRANR group. No surgical intervention was required for the aortic valve in either group. ASO using the CRANR technique did not increase the incidence of postoperative early and late AR.

Transposition of Great Arteries with Complex Coronary Artery Variants: Time-Related Events Following Arterial Switch Operation

Coronary artery anatomy represents a challenging and, often, determining predictor of outcome in an arterial switch operation (ASO). Impact of specific coronary artery variants, such as single, intramural and inverted, on time-related events following ASO, is, yet, to be determined. We sought to compare early and late outcomes within the group of nonstandard coronary artery variants. Patients who underwent ASO from January 1995 to October 2010 were reviewed. Patients with coronary artery variants other than L1Cx1R2 ("standard" by Leiden classification) were included. Patients with single, intramural and inverted coronary artery variants incorporated in group A. All other nonstandard coronary variants incorporated in group B. Demographics, perioperative variables, early and late outcomes were assessed. Of the 123 ASO, 24 patients (19.5%) with nonstandard coronary variant were studied. Thirteen were in group A and 11 in group B. There were two early deaths (1 in group A and 1 in group B) (p > 0.05). There is one death early after hospital discharge (group A). Mean follow-up was 59.4 ± 55.1 months. There was no structural coronary artery failure after hospital discharge following ASO. Freedom from any reintervention at 8 years was (78.3 ± 9.6%) (p 0.55) with no late neo-aortic or mitral valve intervention. ASO with single, intramural or inverted coronary artery course carries no added longitudinal risk for structural or flow impairment within the group of nonstandard coronary artery variants. There is an early hazard period with no late survival attrition. Aortic arch repair as part of staged strategy prior to ASO might influence early and late outcome.

Past, present, and future of the arterial switch operation: historical review

The arterial switch operation is the extant surgical correction after a long series of palliations attempted and/or successfully achieved for the treatment of discordant ventriculoarterial connections. As early as 1954, pioneers such as Mustard, Bailey, Kay, and Idriss led the way with at first disheartening failures, temporarily leading to abandoning the procedure. The first successful atrial baffle procedure in 1958 established itself as the procedure of choice for treating discordant ventriculoarterial connections, but tenacity, courage, and vision to pursue anatomic correction finally led to the first successful arterial switch in 1975 by Jatene. After a decade to perfect surgical technique and timing indications for the various anatomic subtypes, the new era of the neonatal arterial switch since the late 1980s set the very high standards that we all know and expect today. Despite excellent early and long-term survival, important residual lesions are increasingly being recognised. Expected anatomic residuals include supravalvar pulmonary stenosis, neoaortic valve insufficiency, and coronary ostial stenosis. Reinterventions and rare, but challenging surgical reoperations address these residual findings with satisfactory outcomes. Quality of life into young adulthood is satisfactory, but functional problems include reduced exercise capacity, diffuse coronary insufficiency, and neurodevelopmental shortcomings, of which the true incidence and potential clinical implications are still unknown. The arterial switch is a spectacular anatomic correction for a once lethal condition and currently the best surgical solution for patients with discordant ventriculoarterial connections. It is, however, far from a true cure; closer and ongoing follow-up for future care will continue to be required.