Aortic dissection and third-degree atrioventricular block in a patient with a hypertensive crisis

Abstract

A 55-year-old man with a history of uncontrolled hypertension was admitted because of an episode of severely elevated blood pressure. An electrocardiogram revealed complete atrioventricular block while imaging showed a dissecting aneurysm of the descending thoracic and abdominal aorta, type B according to the Stanford classification. Laboratory tests revealed significant increases in serum C-reactive protein. Coronary arteriography was performed and was negative for coronary artery disease. A VDD pacemaker was placed, and a combination of 4 antihypertensive agents was used as treatment. Type B aortic dissection may present with a wide range of manifestations. The authors suggest that measurement of C-reactive protein may be used in hypertensive patients to help reflect vascular injury and its degree, progression, and prognosis. Disorders of intraventricular conductivity are rarely seen in both types of dissection of the aorta (type A, B). Atrioventricular conductivity disorders that result in complete atrioventricular block have been reported only in patients with type A dissection (before the bifurcation of the subclavian artery). In this particular case, however, the authors diagnosed an atrioventricular conductivity disorder causing atrioventricular block in a patient with type B dissection. Consequently, the authors speculate that myocardial fibrosis, as a result of long-standing hypertension, could be the main pathogenetic mechanism leading to the development of such phenomena, resulting from a potential expanding of the fibrotic process to the atrioventricular conduction system.

Figure 1

Stanford B dissecting aneurysm of the aorta expanding from the level of the left subclavian artery. (A) True lumen, (B) false lumen, and (C) left subclavian artery.

Figure 2

Aortic dissection. (A) True lumen, (B) false lumen.