Coarctation of the aorta

Paradoxical hypertension after repair of coarctation of the aorta: a review of its causes

Correction of a coarctation of the aorta, an apparent simple cause of hypertension, paradoxically can provoke two hypertensive responses, one of which is potentially fatal. The first, limited to the first 24 hours, occurs in nearly one half of the patients. This is likely due to the high set of the carotid baroreceptors. The second, which may be associated with abdominal pain and, in some, with necrosis of the small bowel as a result of severe arteritis confined to arteries arising from the aorta below the coarctation, develops in about one half of the first responders. Norepinephrine excretion greatly increases for several days, whereas angiotensin levels are elevated for 3 to 4 days. The hypertension responds to beta-blockers, to arterial smooth muscle relaxants, and to angiotensin converting enzymes. A theory is advanced to explain the second response. It is the adaptation gone awry that ensures adequate flow to exercising muscles below the coarctation, above and beyond that delivered by increasing the systolic pressure. It could be a regionally controlled mechanism similar to the rationing of blood flow in diving mammals.

Coarctation of the aorta in infants and children: 25 years of experience

Repair of coarctation of the aorta was performed in 334 patients ranging from less than a year to 16 years of age at Children's Hospital of Pittsburgh from 1953 to 1977. Resection and end-to-end anastomosis were performed in 310, interposition grafts in 7, and other procedures in 17. There were 41 operative deaths among the 95 infants less than 1 year old (43% mortality); all of these infants had associated cardiac anomalies. Only 1 operative death occurred in patients older than a year (0.4% mortality). No hospital deaths occurred in patients with isolated coarctation of the aorta. Eleven late deaths were due to associated anomalies (7) and unrelated or unknown causes (4). Postoperatively, hemorrhage occurred in 7, paradoxical or persistent hypertension in 128, postcoarctectomy syndrome in 32, neurological problems in 14, pulmonary complications in 53, and infections in 12 patients. Restenosis occurred in 26 patients (8%); only 10 have required reoperation. Residual hypertension was present in 28 of 264 patients (11%). Mortality from coarctation resection remains high in infants, but is minimal in children older than 1 year. Based on minimizing the risk of restenosis and residual hypertension, elective repair of coarctation is recommended when the patient is about 6 years of age.

Successful outcome of complications of excision of aortic coarctation

A case is described of a patient who made a complete recovery following unusually serious complications of excision of aortic coarctation. The thoracic aorta was reconstructed successfully using an aortic graft along a course which appears to be short and direct.

Surgical management of coarctation of the aorta with minimal collateral circulation

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Coarctation of the aorta

In a series of 70 patients who had surgical correction of coarctation of the aorta between 1952 and 1969, the operative mortality was 7% and the complication rate was 14%. The mortality was particularly high in adult males over 30, with pre-operative evidence of left ventricular ischaemia. Simple surgical procedures had satisfactory results, but the use of prostheses carried a high risk, and turning down the left subclavian artery failed to lower the blood pressure. The blood pressure score fell by 68% after operation, and by a further 8% following discharge from hospital. This result was maintained up to 17 years after operation, and may be expected in all groups of patients.

Coarctation in the Elderly

The clinical presentation and operative results have been assessed of a series of patients with coarctation over the age of 40, and have been compared with a larger group of all ages.

Long-standing hypertension increased markedly the incidence of symptoms due to left ventricular strain and cerebral hypertension. There was little increase in symptoms due to poor peripheral blood flow and no case of subacute bacterial endarteritis.

The preoperative systolic blood pressures, when related to the normal for the age and sex of the patient, were higher and the diastolic pressures lower than an average group but signs of left ventricular strain were more common.

At operation the aortic narrowing was found to be of usual severity. Grafts were necessary because of poor anastomotic tissue rather than long narrow segments as in the larger group. The operative mortality was doubled in the elderly, due entirely to hemorrhage from friable aortas. Morbidity was increased as a result of pulmonary and pleural complications.

Postoperative blood pressures were almost exactly comparable with those of the over-all group when related to normal for age and sex. Symptoms were usually relieved but there was relatively slight radiologic or electrocardiographic change. The operative mortality and morbidity are acceptable in view of the risks of inaction and the satisfactory results of operation in the survivors.

Multiple and Infraductal Coarctations of the Aorta

Reports of multiple and infraductal coarctations are appearing more frequently in the literature as interest in the treatment of cardiovascular disease grows.

A case with 4 distinct coarctations is presented.

The Growth of the Normal Aorta and of the Anastomotic Site in Infants Following Surgical Resection of Coarctation of the Aorta

Observations were made on the growth of the anastomotic site 2 to 4 years after surgical resection of coaretation of the aorta in 5 infants who were less than 2 years of age at the time of surgery. Aortic measurements were made from biplane angiocardiograms. The physiologic adequacy of the anastomotic site was demonstrated by absence of a gradient in direct pressure measurements between the upper and lower extremities. Additional observations on the normal growth of the descending thoracic aorta were made from studies in 154 subjects with other forms of heart disease. They ranged in age from 2 days to 74 years.

Coarctation of the aorta proximal of the left subclavian artery: experience with six surgical cases

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Neurologic complications of aortic surgery

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Postoperative changes in the electrocardiogram in congenital heart disease. II. Coarctation of the aorta and patent ductus arteriosus

Electrocardiograms of 41 cases of coarctation and of 73 cases of patent ductus arteriosus were analyzed before and after surgical correction of the defect. The changes in the electrocardiogram which occurred after surgical repair of the coarctation were considered to be due to the diminished load on the left ventricle. In 65 of the cases of patent ductus arteriosus, electrocardiographic signs of left ventricular hypertrophy were recorded. Eight patients, seven of whom presented atypical murmurs, showed evidence of right ventricular or combined ventricular hypertrophy. Following ligation of the ductus, the electrocardiogram became normal in the majority of the cases.