Surgical repair of coarctation of the aorta in neonates: factors affecting early mortality and re-coarctation

Restenosis Rate and Reinterventions after Aortic Arch Repair in Infants

The aim. This study aims to determine the reintervention rate in infantsundergoing aortic arch repair and to analyze risk factors and evaluate the results of reinterventions. Materials and methods. This retrospective study examines 445 infants with aortic arch hypoplasia who under-went aortic arch reconstruction between 2011 and 2019. The study included only patients with two-ventricle physiology and subsequent two-ventricle repair. Techniques for primary repair included extended end-to-end anastomosis (n = 348), end-to-side anastomosis (n = 611), autologous pericardial patch repair (n = 16). Results. The overall mortality in the entire study group was 3.3 %. Follow-up period ranged from 1 month to 9.4 years (mean 2.8 ± 2.5 years). Restenosis at the site of aortic arch repair was identiϐied in 47 (10.5 %) patients. Of these, 12 patients underwent surgical reconstruction of the aortic arch, 27 patients underwent balloon angioplasty, and in 8 patients both methods were used. Freedom from reintervention was 89.4 % at 1-year follow-up and 87.5 % at 4-year follow-up. The most determining factorsfor restenosis were related to hypoplastic proximal aortic arch and body weight less than 2.5 kg. Conclusions. Surgical treatment of aortic arch hypoplasia in newborns and infants is effective and shows good immediate and long-term results. Anatomical correction of reobstruction at the level of the aortic arch is safe with both endovacular and surgical methods with low mortality and incidence of repeated interventions. Identified risk factors for mortality and recurrent aortic arch interventions help to improve the treatment of aortic arch hypoplasia in patients under 1 year of age.

Prediction of recurrent coarctation by early postoperative blood pressure gradient

OBJECTIVE

Blood pressure gradients that are noted early after repair of coarctation in neonates and infants are often attributed to proximal arch hypoplasia. Rapid growth of the hypoplastic proximal arch is usually observed, although in some individuals an early gradient predicts the subsequent need for reintervention. To define the predictive reliability of blood pressure gradients between arms and legs and to identify predictors of arch growth, we undertook a retrospective study.

METHODS

Between January 2000 and June 2008, 77 infants underwent surgical repair of coarctation. Data collected included preoperative dimensions of aortic segments. Blood pressure gradients between arms and legs determined by cuff were compared intraoperatively and postoperatively, as well as 2-dimensional echocardiographic dimensions of the aorta between those who did not require reintervention for recoarctation (group A) and those who did (group B). Receiver operating characteristic curve analysis was applied to evaluate discrimination of the systolic gradient in differentiating the 2 groups of patients.

RESULTS

At surgery, patients' median age was 10 days and weight was 3.3 kg. There was 1 early death. Median follow-up was 40 months (interquartile range, 24-63 months). Recoarctation developed in 11 patients (14.3%), defined as a resting blood pressure gradient of greater than 20 mm Hg with a corresponding decrease in the diameter of the aorta by 50%. Freedom from recoarctation was 87% at 1 year and 85% at 5 years. Multivariable logistic regression analysis identified the size of the ascending aorta as a risk factor for recoarctation. Blood pressure gradient at the end of surgery was not predictive of recoarctation. The ascending aorta and transverse arch showed rapid growth in group A, and this was associated with a decrease in blood pressure gradient over time. In comparison, the growth of the ascending aorta and arch in group B was significantly less than in group A and associated with worsening of gradients. Receiver operating characteristic curve analysis revealed that gradients at the time of hospital discharge (>13 mm Hg) had excellent discriminative accuracy in identifying patients in whom subsequent recoarctation developed.

CONCLUSIONS

Small size of the ascending aorta is a risk factor for recoarctation. Limb gradient in the operating room at completion of surgery is not a reliable tool to assess repair of coarctation, although the gradient at the time of hospital discharge can be used to accurately predict recoarctation. Rapid growth of both the ascending and the transverse aorta is frequently observed and associated with improvement in gradients over time.

Aortopulmonary index as a novel morphologic correlate of early recurrence of coarctation of aorta after surgical repair in infancy

BACKGROUND

The aim of this study was to determine morphologic correlates of early reintervention for recurrent coarctation in infants undergoing surgical repair in the current era.

METHODS

Medical records of infants who underwent repair of coarctation were retrospectively reviewed. Z scores for aortic segments, relative aortic arch segmental dimensions (indexed to ascending or descending aortic dimension), and aortopulmonary index (the ratio of aortic to pulmonary annular diameter) were derived from preoperative echocardiograms.

RESULTS

Eighty-seven patients underwent repair (median age, 13 days). Early arch reintervention (<1 year after surgery) was performed in 11. Lower aortopulmonary index and Z scores of the aortic annulus and sinotubular junction were associated with early reintervention. Aortopulmonary index < 0.6 was the best correlate (sensitivity, 72.7%; specificity, 73.7%; area under the curve, 0.732). Aortic arch dimensions were not correlated with early reintervention.

CONCLUSION

In the current era, aortopulmonary index rather than aortic arch hypoplasia is correlated with the need for reintervention for recurrent coarctation within 1 year of surgery.

Recurrent arch obstruction after repair of isolated coarctation of the aorta in neonates and young infants: is low weight a risk factor?

BACKGROUND

Repair of aortic coarctation is often delayed in small infants because of the belief that such patients are at risk of recurrent arch obstruction and that growth will decrease this risk. To determine whether low weight was a risk factor for recurrent arch obstruction, we reviewed our experience with coarctation repair via left thoracotomy in infants less than 3 months of age.

METHODS

From 1990 to 1999, 103 patients less than 3 months of age underwent repair of aortic coarctation through a left thoracotomy. Median age was 18 days (1-90 days), with 45 patients less than 2 weeks. Median weight was 3.3 kg (1.0-6.4 kg) and 14 patients were less than 2 kg. The method of repair was resection and end-to-end anastomosis in 64 patients, subclavian flap angioplasty in 34, and patch augmentation of the arch in 5. Demographic, echocardiographic, and operative variables were analyzed for correlation with recurrent arch obstruction.

RESULTS

One early and 1 late death occurred, both in patients who had complications but no evidence of recoarctation. At median follow-up of 24 months, reinterventions for recurrent arch obstruction were performed in 15 patients. The median time to reintervention was 5 months and was less than 1 year in 12 patients. Kaplan-Meier freedom from arch reintervention was 88% at 1 year (95% confidence intervals: 82%-94%) and 82% at 5 years (95% confidence intervals: 72%-92%). Factors associated with shorter duration to arch reintervention by univariable Cox regression included younger age (continuous, P =.01; <2 weeks, P =.005), smaller transverse arch (absolute diameter, P <.001; indexed to weight, P =.03; indexed to ascending aortic diameter, P =.02), and smaller ascending aorta (absolute diameter, P =.02). Smaller absolute transverse arch diameter and younger age were the only independent predictors of shorter time to arch reintervention by multivariable Cox regression analysis. Weight and type of repair did not correlate with risk of recoarctation.

CONCLUSIONS

Low weight is not a risk factor for recurrent obstruction after repair of coarctation of the aorta in infants less than 3 months of age. Rather, risk of recoarctation is more a function of the anatomy of the arch. Thus, it is not indicated to delay repair in low weight infants with the goal of achieving growth.

Surgery for coarctation of the aorta in infants younger than 3 months: end-to-end repair versus subclavian flap angioplasty: is either operation better?

OBJECTIVE

Recurrent coarctation is a complication which is seen at a consistent rate following all types of repair for coarctation of the aorta. Particularly disappointing late results are reported in younger infants, under 3 months of age. This retrospective analysis was undertaken to compare the outcomes on late follow-up between subclavian flap angioplasty and resection and end-to-end repair, in this age group.

METHODS

Over a 12-year period, between 1982 and 1994, 86 infants under 3 months of age underwent surgical repair of coarctation (39 resections and end-to-end repair, and 47 subclavian flap angioplasty procedures). Operative mortality was not significantly different (P = 0.6) between resection and end-to-end repair (5.1%) and subclavian flap angioplasty (8.5%). All operative deaths (six patients) were in infants with associated ventricular septal defects. The mean follow-up for all patients was 7.95 years +/- 4.10 (range 0-14.5 years). The 5-year survival for resection and end-to-end repair was 87 +/- 5%, compared to 75 +/- 7% for subclavian flap angioplasty (P = 0.2).

RESULTS

Recurrent coarctation occurred in nine patients who needed reoperation. The reoperation-free rates at both 5 and 10 years for resection and end-to-end anastomosis, and subclavian flap repair were 86 +/- 6% and 90 +/- 5%, respectively. The recurrence in the resection and end-to-end anastomosis group were due to constrictive scarring at the anastomosis, whereas periductal tissue and growth of posterior aortic ridge caused recurrence in the subclavian flap angioplasty group. There were no deaths during reoperation for recurrence.

CONCLUSIONS

Both procedures are extremely effective for coarctation repair in young infants and run a similar risk of recurrence, which are due to completely different mechanisms. The surgeon's expertise is the major determinant of outcome.

Influence of prenatal diagnosis on congenital heart defects

The impact of prenatal detection of congenital heart defects (CHD) using the four-chamber screening examination cannot be accurately ascertained because of the wide range of detection rates that affect the cost associated with it. Assuming a screening ultrasound cost of $200 per examination, recent studies in which examiners not trained in fetal echocardiography obtained and interpreted the four-chamber view only identified 5.3% of CHD, for a cost of $476,190 per malformation. When the four-chamber screening examination was performed by an individual trained in fetal echocardiography, the detection rate increased to 55%, for a cost of $45,454 per malformation. This resulted in a savings of 90%, or $430,736. Because individuals trained in fetal echocardiography are not available to perform and interpret all of the heart screening examinations, another approach is for the fetal echocardiographer to review one to two minute video clips of the four-chamber and outflow tracts screening examination obtained by the individual performing the fetal screening examination. It is estimated that at a charge of $30 per video clip review, the cost to detect 50% of CHD would be $7,500 per defect. This would result in a reduction of 98% for the detection of CHD using current screening methods. This approach would increase the detection rate of CHD by 10-fold, remove the liability of missing CHD from the untrained individual performing the screening examination, and provide revenue to tertiary centers in which individuals skilled in fetal echocardiography could maximize their diagnostic skills.