Early and Mid Term Results of Surgical Repair of Coarctation of the Aorta: Experience of Benha in 19 Patients with simple Coarctation of the Aorta

Alaa Gafar MD, Mohamed Khairy MD, Yousry El-Saied MD, Yousry Shaheen, MD, Aly Abdel- Samea MD, Ahmed Ali MD.

Department of Cardiothoracic Surgery, Benha Faculty of Medicine,

Benha University, Egypt

Abstract

Objective: To evaluate early and mid term results of surgical repair of coarctation of the aorta in patients with isolated (simple) coarctation of the aorta.

Patients and methods: Between March 2000 and February 2005, nineteen patients diagnosed as cases of isolated coarctation of the aorta (with or without PDA) using Echocardiography .They underwent resection of the coarcitated segment with end-to-end anastomosis. The patients were followed up for a mean period 23.8 ± 7.4 months. In each visit, the patient clinically evaluated for blood pressure, gradient (by echocardiography), neurological and recoarctation symptoms

Results: the age ranged from 6 months to 9 years (mean of 4.4 ± 2.8 years) and 12 patients of them (63%) were males. The patients presented with different symptoms in the form of claudications in 12 patients (63%), headache in 10 patients (54%), chest pain in 3 patients (16%), and repeated chest infections in 7 patients (36%). On examination, 14 patients (73%) had weak femoral pulse, and 11 patients (58%) had systolic continuous murmur conducted to the back. All the patients had hypertension which was defined as blood pressure greater than that of the 90th percentile for age, On measuring blood pressure, the mean upper limb blood pressure was 129/83 ± 6.7/5.7 mm Hg, and the mean gradient was 35.4 ± 6.8mm Hg. Operatively, the mean operative time was 149.2 ± 14.6 minutes, the mean cross clamp time was 25.7 ± 2.4 minutes, the mean intercostal tube (ICT) period was 2.7 ± 0.8 days, the mean ICU stay was 1.6 ± 0.6 days and the mean hospital stay was 9.9 ± 1.6 days. There was no operative or hospital mortality. There was immediate postoperative increase in mean blood pressure which was 131/82 ± 6/3 mm Hg, this increase was controlled with infusion of antihypertensive drugs. However, all the patients had dramatic improvement in blood pressure before discharge as the mean blood pressure on discharge was 114/67 ± 6/4 mm Hg and the mean gradient on discharge was 13.3 ± 5.1mm Hg. On follow up, the signs of hypertension occurred in total of 4 patients (21%), unfortunately, 2 of them died due to heart failure (11 and 15 months postoperatively). The other 2 patients with post operative hypertension were on one antihypertensive medication to control blood pressure. There was significance difference (P Value less than 0.05) between both mean blood pressure as well as mean gradient on admission and both on discharge, also there was significance difference between both mean blood pressure and mean gradient on admission and both on 30 months after surgery.

Conclusion: Surgical repair of isolated coarctation of the aorta by the technique of excision of the coarcitated part with end-to-end anastomosis is essential in young patients to avoid subsequent morbidity and premature mortality. The short term and midterm results were satisfactory and encouraging

Introduction:

Coarctation of the aorta accounts for approximately 5% of all congenital heart diseases and is defined as a congenital narrowing of the aorta. The narrowing is most commonly located just distal to the origin of the left subclavian artery (Ad & Vidne, 1999). Traditionally, coarctation was classified into infantile (preductal) and adult (postductal) types, however, this classification is often misleading because age of the presentation was found to be related more to the degree of narrowing and the presence of associated abnormalities than to the location. The term simple aortic coarctation refers to an isolated abnormality in the absence of any other cardiovascular lesion except patent ductus arteriosus (PDA) (Konen et al, 2004). Untreated coarctation of the aorta is associated with premature mortality and morbidity with a median age at death of 31 years (Hoimyr et al, 2006) and (Bauer et al, 2001).The first surgical repair of coarctation of the aorta was performed by Crafoord and Nylin in 1945 (Hopkins et al, 1988). Different studies revealed that the classical repair involving resection of the coarcitated part with end-to-end anastomosis has resulted in decreased the incidence of recoarctation and aneurysm formation (Brouwer et al, 1994).

In this study, we reviewed the early and mid term results of our experience in elective surgical repair of coarctation of the aorta in 19 patients with isolated (simple) coarctation of the aorta.

Patients and Methods:

Between March 2000 and February 2005, nineteen patients diagnosed as cases of isolated coarctation of the aorta (with or without PDA), were admitted to our hospital. The age of our patients ranged from 6 months to 9 years (mean was 4.4±2.8years).

The diagnosis was made by characteristic signs and symptoms, and confirmed by echocardiographic evaluations. The upper limb blood pressure, lower limb blood pressure and the gradients between them were measured and evaluated. In all patients we used the technique of resection of the coarcitated part with end-to-end anastomosis (We exclude all the other 12 older patients in whom we used the technique of the aortic repair with Dacron patch). The results of the surgery in the form of operative time, cross clamp time, the period of intercostal tubes, ICU stay, and hospital stay were evaluated. Operative mortality, immediate and on discharge blood pressure as well as gradient were measured and confirmed by echocardiographic evaluations.

The patients were followed up for a period ranged from 11 months to 30 months (mean was 23.8 ± 4.4 months) in regular bases at 3, 9, 18 and 30 months postoperatively. In each visit, the patient evaluated for blood pressure, gradient (by echocardiography), neurological symptoms and other morbidity, signs of recoarctation as well as mortality.

The preoperative results, immediate postoperative results as well as the results of each visit were collected, compared and statistically analyzed.

Technique of surgery:

The surgical approach in all patients was through a left posterolateral thoracotomy in the 4th intercostal space, which provided adequate exposure. Great care should be taken to the 1st intercostal arteries to avoid ligation or tearing. The aortic arch, the brachiocephalic vessels and descending thoracic aorta were dissected free to help mobilization of the aorta for easy resection and anastomosis, Patent ductus arteriosus or ligamentum arteriosum was transected and sutured, after application of the aortic cross clamps proximally just distal to the subclavian artery and distally below the anticipated incision line and used to apply traction (pulling) the descending thoracic aorta up to the anastomosis. Resection of the coarcitated part of the aorta was done. Then traction on the upper and lower clamps allowed the 2 aortic ends to come together. The anastomosis was contracted with 7/0 or 6/0 polypropylene sutures, continuous posteriorly and interrupted anteriorly (in 8 infants and younger patients), 4/0 or 5/0 polypropylene in the eleven older patients anastomosis was done using continuous sutures. The thoracotomy incision was closed in layers after insertion of a single intercostal tube for 24-48 hours according the amount of drainage. The patients then transferred to ICU with close monitoring of blood pressure by invasive and non-invasive techniques.

Results:

This study included 19 patients with isolated coarctation of the aorta, 6 of them (31 %) were with PDA and the other 13 patients (69%) were without PDA, the age ranged from 6 months to 9 years (mean of 4.4 ± 2.8 years) and 12 patients of them (63%) were males. The patients presented with different symptoms (Table I) in the form of claudications in 12 patients (63%), headache in 10 patients (54%), chest pain in 3 patients (16%), and repeated chest infections in 7 patients (36%). On examination, 14 patients (73%) had weak femoral pulse, and 11 patients (58%) had systolic continuous murmur conducted to the back. All the patients had hypertension which was defined as blood pressure greater than that of the 90th percentile for age, 5 patients (26%) were on one antihypertensive drug, 2 patients (10%) on 2 medications and one patient (5%) on 3 medications. On measuring blood pressure, the mean upper limb blood pressure was 129/83 ± 6.7/5.7 mm Hg and the mean lower limb blood pressure was 70/42 ± 5/5 mm Hg and the mean gradient between the precoarctation and the postcoarctation was 35.4 ± 6.8mm Hg.

Table I : Presentations of 19 patients with coarctation of the aorta:

Presentation / No of patients
Mean Age / 4.4 ± 2.8 years
Claudications / 12/19 (63%)
Headache / 10/19 (54%)
Chest Pain / 3/19 (16%)
Repeated Chest Infections / 7/19 (36%)
Mean Blood Pressure / 129/83 ± 6.7/5.7 mm Hg
Mean Gradient / 35.4 ± 6.8mm Hg
Weak Femoral pulse / 14/19 (73%)
No femoral pulse / 5/19 (26%)
Heart Murmur / 11/19 (58%)
PDA / 6/19 (31%)

Operative results were summarized in table II, the mean operative time was 149.2 ± 14.6 minutes, the mean cross clamp time was 25.7 ± 2.4 minutes, the mean intercostal tube (ICT) period was 2.7 ± 0.8 days, the mean ICU stay was 1.6 ± 0.6 days and the mean hospital stay was 9.9 ± 1.6 days. The post operative course was smooth in all patients except 2 patients (10%) as the period of ICT was longer than others due to more amount of serosanginuous drained fluid which gradually decreased in volume till the removal of the tube. There was no operative or hospital mortality.

Table II: Operative Results:

Item / Results
Mean Operative Time / 149.2 ± 14.6 minutes
Mean Cross Clamp Time / 25.7 ± 2.4 minutes
Mean Immediate Blood Pressure / 131/82 ± 6/3 mm Hg
Mean ICT Period / 2.7 ± 0.8 days
Mean ICU Period / 1.6 ± 0.6 days
Mean Hospital Stay / 9.9 ± 1.6 days
Mean Period of Decreased Blood Pressure / 4.2 ± 1.3 days
Mean Blood Pressure on Discharge / 114/67 ± 6/4 mm Hg
Mean Gradient On Discharge / 13.3 ± 5.1mm Hg
% of Decrease of Systolic Blood Pressure/
% of Decrease of Diastolic Blood Pressure / 11.7% /
19 %

There was immediate postoperative increase in mean blood pressure which was 131/82 ± 6/3 mm Hg, this increase was controlled with infusion of nitroprusside, nitroglycerine or β-blockers. However, all the patients had dramatic improvement in blood pressure before discharge as the mean blood pressure on discharge was 114/67 ± 6/4 mm Hg and the mean gradient on discharge was 13.3 ± 5.1mm Hg.

On follow up period (Table III), the mean blood pressure measurements were satisfactory in all visits and the mean gradient measurements were less than 20 mm Hg in all visits, these also were satisfactory. The signs of hypertension occurred in total of 4 patients (21%), 2 patients (10%) within 3 months after surgery, another one patient (5%) within 18 months after surgery and the last one (5%) within 30 months after surgery. Unfortunately, the 2 patients (10%) who had signs of hypertension within 3 months after surgery died due to heart failure (11 and 15 months postoperatively). The survived 2 patients with post operative hypertension were on one antihypertensive medication to control blood pressure.

Table III: Follow up:

Item / 3 Months / 9 Months / 18 Months / 30 Months / Total
Mean Blood Pressure / 107/64 ± 9/10 mm Hg / 109/64 ± 10/11 mm Hg / 113/72 ± 9/10 mm Hg / 113/73 ± 5/6 mm Hg
Mean Gradient / 15 ± 6.7mm Hg / 17 ± 9mm Hg / 17 ± 8mm Hg / 16 ± 4mm Hg
Signs of Hypertension / 2/19 (10%) / No / 1/19(5%) / 1/19(5%) / 4/19(21%)
Mortality / No / No / 2/19(10%) / No / 2/19(10%)

Table IV shows the statistical significance difference (P Value ≤ 0.05) between the mean blood pressure and the mean gradient on admission and that on discharge as well as the statistical significance difference between the mean blood pressure and the mean gradient on admission and that on 30 months after surgery.

Table IV: P Value Of Mean Blood Pressure and Gradient before, after surgery and on follow up:

On Admission / On Discharge / P Value / On 30 Months / P Value
Mean Blood Pressure / 129/83 ± 6.7/5.7 mm Hg / 114/67 ± 6/4 mm Hg / 0.0001/0.00006 / 113/73 ± 5/6 mm Hg / 0.0002/0.003
Gradient / 35.4 ± 6.8mm Hg / 13.3 ± 5.1mm Hg / 0.000004 / 16 ± 4mm Hg / 0.00002

Discussion:

Coarctation of the aorta accounts for approximately 5-7% of all live births with congenital heart diseases (Rosenthal, 2005). Coarctation of the aorta is a congenital malformation that can lead to premature death if it remains uncorrected, 50% of the patients die by the age of 30 years, 75% at 46 years and 90% at the age of 58 years (Aris et al, 1999). The 1st clinical surgical repair of coarctation of the aorta was reported by Crafoord and Nylin in 1945. Several series have short-term success of coarctation repair in terms of decreased mortality and a decrease in hypertension (Buchart et al, 2000).

Our study carried out on 19 patients with isolated coarctation of the aorta (with or without PDA) to evaluate short term and midterm results of surgical repair of coarctation of the aorta by technique of resection with end-to-end anastomosis.

The mean age of our patients was 4.4±2.8 years (ranged from 6 months to 9 years), this was related to that stated by Brouwer et al, 1994, that the ideal age for elective aortic coarctation repair was supposed to be between 4 years and adolescence to avoid the high mortality in neonates. Gradually the timing for elective repair of coarctation of the aorta has shifted towards infancy, in another series the mean age at the time of surgical intervention was younger and it was 1.85±3.1 years (Walhout et al, 2003).