Transverse Arch Hypoplasia Research Articles

Extended Resection and End-to-End Anastomosis for Aortic Coarctation in Infants: Results of a Tailored Surgical Approach

The surgical repair of aortic coarctation in infants has evolved over time. This study evaluates our current approach utilizing extended end-to-end anastomosis without prosthetic material to enlarge all areas of aortic arch hypoplasia. The Michigan Congenital Heart Center database was reviewed for infants who underwent repair of isolated aortic coarctation from January 1, 1990, to January 1, 2000. Eighty-three infants underwent surgical repair of isolated coarctation during this decade. Median age at repair was 21 days (range, 2 to 365). Repair was performed through thoracotomy in 72 patients. Because of severe transverse arch hypoplasia, the remaining 11 infants underwent median sternotomy with circulatory arrest. There were 2 deaths: 1 due to pulmonary hypertension in a patient with alveolar capillary dysplasia and 1 late death due to pneumonia in a patient with noncardiac anomalies. Neither patient had residual coarctation. Technique-related complications of bronchial compression, chylothorax, and vocal cord paralysis were noted in 4 patients. Follow-up data were available for 66 patients (80%) with mean follow-up duration of 4.5 years (SD +/- 3.1). Reintervention was required in 4 patients (6%). One underwent reoperation after 1 month, and 3 underwent balloon angioplasty within 7 months of initial repair. The remaining 61 patients are asymptomatic, on no antihypertensive medications, and have aortic arch gradients less than 15 mm Hg. One developed subaortic stenosis necessitating resection. Tailored surgical repair for aortic coarctation has a low rate (6%) of residual and recurrent coarctation even when performed in infants. Mortality and morbidity are low.

Transverse arch hypoplasia may predispose patients to aneurysm formation after patch repair of aortic coarctation

Background Thoracic aortic aneurysm after patch repair of aortic coarctation is a potentially lethal complication. We hypothesized that transverse arch hypoplasia in association with patch repair of aortic coarctation predisposes aneurysm formation. Methods A retrospective analysis was performed on all patients undergoing isolated aortic coarctation repair at the University of Virginia Health Systems between 1970 and 1995. Of 244 repairs, 38 patients underwent patch repair. These 38 patients were divided into two groups. The aneurysm group (n = 15) had aortic aneurysms develop at the repair site, which required aneurysmectomy. The nonaneurysm group (n = 23) did not have any aneurysms develop. Univariate analysis and Fisher's exact text were used to identify factors that independently predict aneurysm formation. Results Univariate analysis demonstrated aortic arch hypoplasia associated with patch repair independently predicts future aneurysm formation ( p < 0.01). Patients who had an aneurysm develop also had a similar incidence of bicuspid aortic valves, mild restenosis, and late hypertension compared with patients in the nonaneurysm group. Conclusions Aneurysm formation after patch repair of aortic coarctation develops into a subgroup of patients. Aortic arch hypoplasia associated with coarctation independently predicts future aneurysm formation.

Interventions for aortic coarctation.

The standard treatment of coarctation of the aorta is surgical. In the last 2 decades, however, treatment by catheter intervention has become more widespread, using either balloon angioplasty or primary stent implantation. Balloon angioplasty was originally used for recurrent coarctation after surgical repair but has now been shown equally effective for unoperated coarctation. The procedure produces a satisfactory gradient reduction in approximately 80% of patients, with transverse arch hypoplasia the main predictor of poorer outcome. Rates of restenosis and aneurysm formation are less than 10%. Primary stent implantation has been suggested as an option potentially superior to angioplasty alone. Stent implantation limits elastic recoil and potentially reduces aneurysm formation by reducing the amount of balloon stretch required. The incidence of suboptimal gradient reduction is low, probably 5% or less, as is the rate of restenosis. Aneurysm formation, vascular complications, and stent migration also occur in less than 5%. Catheter interventions are now an established treatment strategy for coarctation, with a good success rate and safety profile. The outcome for native and recurrent coarctation appears similar. The authors believe that for most adult patients with coarctation of the aorta, catheter intervention should be offered as initial therapy.

Transverse arch hypoplasia predisposes to aneurysm formation at the repair site after Dacron patch angioplasty for coarctation

Transverse arch hypoplasia predisposes to aneurysm formation at the repair site after Dacron patch angioplasty for coarctation

Transverse arch hypoplasia predisposes to aneurysm formation at the repair site after patch angioplasty for coarctation of the aorta

Objectives. This study used magnetic resonance imaging (MRI) to evaluate the morphology and pathophysiology of aneurysm formation after patch angioplasty for coarctation of the aorta.Background. Late aneurysm formation at the repair site is a well known and frequent complication after patch angioplasty. However, because the underlying mechanisms remain unresolved, postoperative outcome is unpredictable and adequate follow-up difficult.Methods. Seventy-three of 85 patients with patch angioplasty for coarctation of the aorta were screened for aneurysm formation. Magnetic resonance imaging was performed in all 33 patients with an aneurysm, and results were compared with those for 13 control patients and 10 normal subjects. Mean (±SD) time between operation and MRI was 12.0 ± 2.0 years. Aneurysm was defined as the ratio of the diameter of the aorta at the repair site to the diaphragmatic aorta ≥1.5. Hypoplasia of the transverse arch and recoarctation at the repair site were defined as a ratio <0.9. Transverse arch ratios on MRI were compared with those on preoperative cineangiography and the pressure gradient between the patient's right and left arm.Results. All 33 patients with an aneurysm had a hypoplastic transverse arch. The 13 patients with a normal ratio at the repair site had a normal transverse arch ratio (chi square, p < 0.0001). Logarithmic regression showed a significant negative correlation (r = 0.62) between the repair site and transverse arch ratios. A significant pressure difference between the patient's right and left arm was found in patients with versus those without aneurysm (p = 0.0009). No significant difference was found between transverse arch ratios on preoperative cineangiography and postoperative MRI (mean 0.014 ± 0.1, p = 0.4).Conclusions. Aneurysm formation at the repair site is highly related to hypoplasia of the transverse arch. Sufficient catch-up growth of a hypoplastic transverse arch is rare after late patch angioplasty. Dynamic phenomena, such as flow acceleration and turbulence, originating in a narrow transverse arch, may contribute to aneurysm formation at the repair site after patch angioplasty.

Balloon angioplasty of native coarctation of the aorta: Midterm follow-up and prognostic factors

OBJECTIVES, This retrospective analysis was designed to examine the intermediate and long-term effects of balloon angioplasty for native coarctation of the aorta and to determine whether any factors are predictive of outcome. Balloon angioplasty for native coarctation of the aorta is controversial. Concerns exist over lack of long-term follow-up and possible formation of aneurysms. The role of transverse arch and isthmus hypoplasia after balloon dilation is unknown. Included in the study were all patients 3 days to 29 years old (mean age 4.6 years) referred for possible balloon dilation to the pediatric cardiac catheterization laboratory with evidence of a discrete coarctation of the aorta. The hemodynamic data, angiograms and clinical records of 102 patients were examined, with follow-up data from 2 to 117 months (median 36.2) available in 92 patients. Immediate success with balloon angioplasty was achieved in 93 (91.2%) of the 102 patients. Seventy-one patients (77.2%) with intermediate follow-up data (range 12 to 117 months) available are asymptomatic and normotensive, with insignificant arm to leg blood pressure gradients (< or = 20 mm Hg). Twenty-one patients (22.8%) with an initial successful result developed an increase in gradient 2 at 86 months after angioplasty, requiring reintervention in 18. Follow-up > 72 months is available in 17 patients, 16 of whom are normotensive and have not required additional intervention. No additional intervention was needed in 88.4% of older children and infants > 7 months old. Ten of the 13 surviving neonates who initially had a successful dilation required reangioplasty or operation 14 days to 10 months (median 4.6 months) after angioplasty. Transverse arch hypoplasia had minimal effect on follow-up blood pressure gradient, whereas isthmic hypoplasia was associated with reintervention in 50%. A small aneurysm was noted in 2 (1.9%) of 102 patients. Balloon angioplasty of native aortic coarctation is effective in infants and older children. In neonates, balloon angioplasty provides effective palliation only. Aneurysm formation is rare; however, lifetime follow-up is warranted.

Repair of coarctation of the aorta in children: postoperative morphology.

To determine the morphologic sequelae after surgical repair of coarctation of the aorta, the authors retrospectively reviewed angiograms and hemodynamic and clinical data on 215 patients who underwent cardiac catheterization after surgical repair of coarctation of the aorta during a 13-year period. Ninety-seven patients (45%) underwent coarctation resection with end-to-end anastomosis; 92 (43%), subclavian-flap angioplasties; and 26 (12%), synthetic-patch repairs. Sixty-four patients (30%) had an "aneurysm," defined as a measurement ratio of repair site to diaphragmatic aorta greater than 1.5. Transverse-arch or isthmic hypoplasia or recoarctation was detected in 86 patients (40%) and was most commonly associated with septal defects or obstruction of the left ventricular outflow tract. Pullback systolic pressure gradients at catheterization were significantly higher (P = .0001) in the patients with transverse-arch hypoplasia and recoarctation than in those with ratios of transverse arch to diaphragmatic aorta greater than 0.9. Significant postoperative arch obstructions can be predicted with measurement ratios on the basis of the diameter of the abdominal aorta.

Quantitative morphology of the aortic arch in neonatal coarctation

It has been speculated that neonatal coarctation results from postnatal constriction of the aortic isthmus and ductus arteriosus. However, aortic arch hypoplasia is present in some neonates with coarctation and is presumed to be due to decreased aortic arch blood flow in utero. To measure the degree of aortic arch hypoplasia and to analyze the distribution of blood flow in neonatal coarctation, quantitative morphometric analysis of the great vessels from two-dimensional echocardiograms was performed in 14 neonates with isolated coarctation and 14 normal control neonates, all less than 1 month old. Measurements of the aortic valve, pulmonary valve, ascending aorta, transverse aortic arch between the carotid and subclavian arteries, aortic isthmus, descending aorta, main pulmonary artery and brachiocephalic vessels were obtained to the nearest 0.5 mm. In coarctation patients the transverse arch and isthmus were significantly smaller than in control subjects (p less than 0.001). In addition, pulmonary valve and main pulmonary artery diameters were significantly greater in neonates with coarctation than in normal neonates. Transverse arch hypoplasia and increased pulmonary valve and pulmonary artery diameters are present in neonates with coarctation. This suggests decreased aortic arch flow and increased pulmonary and ductus arteriosus flow in utero, which produce a characteristic echocardiographic appearance of transverse arch hypoplasia with a large main pulmonary artery.