Acute dissection of the aorta: Options for diagnostic imaging
Abstract
When dissection of the aorta is suspected, the physician needs to initiate medical therapy immediately, even before a final diagnosis is made. New imaging technologies are essential in making a diagnosis. In some cases, these new imaging modalities obviate the need for angiography.
Diagnostic clues include an abrupt, intense, ripping or tearing pain in the chest or back, ischemic signs in various organs due to occlusion of branch vessels, and a new murmur of aortic insufficiency. Patients often have underlying hypertension, atherosclerosis, or connective-tissue disease.
Medical therapy should be initiated immediately with intravenous infusions of nitroprusside and concomitant administration of a beta blocker or a calcium antagonist with negative inotropic effects (verapamil or diltiazem). Blood pressure and urine output must be closely monitored to assure adequate tissue perfusion.
Aortography remains the gold standard for imaging procedures. Transthoracic or transesophageal echocardiography, computed tomography, and magnetic resonance imaging all have advantages and disadvantages in certain situations, and are safer than aortography. However, they will not reveal coronary artery disease.
Proximal dissections must be repaired immediately; patients with coronary artery disease can undergo bypass grafting at the same time.
