Acute dissection of the thoracic aorta: experience at the Puerto Rico Medical Center (1991 through 1995)

Abstract

Background: Acute dissection of the thoracic aorta has a very poor prognosis unless promptly diagnosed and treated. The clinical presentation, diagnosis and management of 16 patients was reviewed.

Methods: We identified 12 patients from the Puerto Rico Medical Center and 4 patients from the "Centro Cardiovascular de Puerto Rico y del Caribe" whose diagnosis was made from January 1991 to December 1995. Medical records and autopsy reports were reviewed.

Results: Of the 16 patients, 10 [62%] were males, 10 [62%] were 60 years old or older [range 25 to 85 years], and 15 [93%] had a past history of hypertension although only 6 [38%] were found with an initial blood pressure of 140/90 or higher. Chest pain was the initial symptom in 13 [81%]. Of these 46% [6/13] described it as oppressive, with radiation to back or neck in 38% [5/13]. In none a neurological abnormality was the initial presentation. No physical sign was present in more than 40% of patients. One patient had a diastolic murmur suggestive of aortic regurgitation but none had a pericardial rub or a neurologic deficit. The electrocardiogram showed left ventricular hypertrophy in 35% but none had changes compatible with an acute Q wave infarction. The chest radiography was compatible with dissection in all in whom it was done [8/8]. Computerized tomography of the chest was diagnostic in 6 of 8 patients [sensitivity 75%]. Aortography had a sensitivity of 80% [4/5]. Trans-thoracic echocardiogram was diagnostic in 3 of 4 patients [75% sensitivity]. Transesophageal echocardiogram had a 100% sensitivity [2/2]. In 8 patients [50%] the correct diagnosis was made by postmortem examination, all of whom died within 24 hours of Emergency Room's evaluation. Of those properly diagnosed 5 died without being surgically intervened. Only one survived surgery [1/3] Overall mortality was 93%. The most common pathological finding was Type A dissection in 14 [88%]. Cardiac tamponade was found in 9 [56%]. Hemothorax was found in 6 [38%]. Aortic valve insufficiency was reported in 20% and coronary artery involvement in 28%.

Conclusions: The dismal prognosis traditionally associated with acute dissection of the thoracic aorta remains unchanged. Prompt diagnosis based on high clinical suspicion. followed by expeditious medical and surgical treatment are fundamental to change the natural course of this condition.