The catheterization lab held the key to diagnosis in a patient who noted only mild neck discomfort.
Joe, age 67, presented to the emergency department (ED) after a near-syncopal episode that came on while he was eating dinner. He reported nausea, diaphoresis, light-headedness, and generalized weakness. In addition, he noted palpitations and mild left-sided neck discomfort without radiation. Joe denied chest pain, back pain, shortness of breath, headache, focal weakness, abdominal pain, fever, vomiting, or diarrhea. His only significant medical history was hypercholesterolemia; there was no history of diabetes or hypertension. Joe said he drank occasionally. He denied smoking or using illicit drugs, and he had no allergies. His only medication was simvastatin (Zocor). Family history was unremarkable. He had returned just two days before from India.
In the ED, Joe was diaphoretic and pale. He appeared well-nourished. Vital signs were pulse 140 beats per minute, BP 82/51 mm Hg, respiratory rate 22 breaths per minute, temperature 98°F, and oxygen saturation on pulse oximetry 98%. His neck was nontender, with no bruits.
On cardiac examination, his pulse was irregularly irregular. His lungs were clear. He had no pedal edema or calf tenderness. Neurologic examination found no focal deficits. His skin felt wet and cool; he did not have any rashes.
Joe’s routine blood work was normal. The ECG revealed atrial fibrillation with inferior and lateral ST-segment elevations. Chest x-ray was clear, with no abnormalities. An immediate cardiology consult was obtained. We drew blood for cardiac enzymes and D-dimer levels.
The patient was given a liter of normal saline for his hypotension as well as aspirin, clopidogrel (Plavix), and heparin for the possibility of MI. Beta blockers were held because of the hypotension. Vital signs repeated after a fluid bolus were BP 102/64 and heart rate 130 beats per minute. Joe was immediately sent to the catheterization laboratory.
We were all surprised to find that Joe had a proximal aortic dissection with no history of chest or back pain. The dissection involved the arch of the ascending aorta and traversed down to the base of the heart, causing incompetence of the aortic valve, as well as occlusion of the right coronary artery (RCA). The result was ischemia in the distribution of the RCA. Joe underwent immediate aortic valve and arch replacement.
Unfortunately, patients who present with cardiac ischemia are often given aspirin, heparin, clopidogrel, and thrombolytics, which can lead to fatal events in those with aortic dissections. In >90% of patients with dissections, the clinical presentation is abrupt, severe pain, often described as tearing,1 in the chest or between the scapulae.
Our patient experienced only a mild discomfort in his neck with no chest or back pain. A significant number of patients do present with a “silent” (painless) aortic dissection. They may have only ischemic or neurologic findings.2-6
Symptoms of aortic dissection depend on the location of the lesion. Dissection into a carotid artery may result in a classic stroke presentation. Abdominal or flank pain may result from dissection into the abdominal aorta, renal arteries, or iliac arteries. Nausea, vomiting, and diaphoresis are common.1 Patients with aortic dissections are usually 50-70 years old with a history of hypertension. Risk factors include connective tissue disorders, pregnancy, trauma, and tobacco use.2
Most patients will have a normal heart and lung exam. Their skin may feel cool and clammy despite an elevated BP. The diastolic murmur of aortic insufficiency may be heard.
Hypertension and tachycardia are commonly present, but hypotension is possible, too, in patients with coronary artery involvement. Decreased pulses should raise suspicion of an aortic lesion. The ischemic end-organ manifestations include MI,3-6 pericardial disease (cardiac tamponade), pulmonary disorders, stroke, musculoskeletal disease of the extremities, spinal-cord injuries, and intra-abdominal disorders. Symptoms may change as the dissection progresses.>sup>1
Thoracic dissections will often (90%) result in an abnormal aortic contour on chest x-ray, including widening of the mediastinum and deviation of the trachea, main-stem bronchi, or esophagus. Intimal calcium may be seen distant from the edge of the aorta, suggesting dissection.1
The ECG is abnormal in most patients with an aortic dissection. The newer helical CT scans have almost 100% specificity and sensitivity for diagnosing aortic dissections and are becoming the preferred diagnostic technique. Aortography is the traditional diagnostic gold standard, and transesophageal echocardiography is the most expedient technique for confirming the diagnosis of aortic dissection.2
Treatment of proximal aortic dissection requires 10-15 units of blood on standby and immediate consultation with a cardiothoracic surgeon. Initial ED management involves controlling the pulse and BP with beta blockers and nitroprusside or labetalol. Hypotensive patients need crystalloid boluses or blood. Dissections involving the ascending aorta are treated surgically in a timely fashion.2
Although Joe’s first set of cardiac enzymes was normal, the second set indicated myocardial ischemia (creatine kinase [CK] 1,142 mU/mL; CK-MB 65 mU/mL [5.7% of total CK]). After 19 days in the hospital, he was discharged home on metoprolol (Lopressor) and warfarin (Coumadin). Joe returned to work after a few months and continues to do well.
Dr. Llovera, Dr. Roit, Dr. Sama, and Dr. Poordabbagh are in the Department of Emergency Medicine, North Shore University Hospital in Manhasset, New York.
1. Tintinalli JE, Kelen GD, Stapczynski JS. Emergency Medicine: A Comprehensive Study Guide. 5th ed. New York, N.Y.: McGraw-Hill; 2000:412-416.
2. Rivers C, Howell J, Barkin R. Preparing for the Written Board Exam in Emergency Medicine. 5th ed. Milford, Ohio: Emergency Medicine Educational Enterprises, Inc.; 2006:128-133.
3. McKechnie RS, Patel D, Eitzman DT, et al. Spontaneous coronary artery dissection in a pregnant woman. Obstet Gynecol. 2001;98(5 Pt 2):899-902.
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5. Papadopoulos DP, Moyssakis I, Perakis A, et al. Acute myocardial infarction due to spontaneous dissection of the right coronary artery in a young male. Cardiovasc Intervent Radiol. 2004;27:536-537.
6. Weiss P, Weiss I, Zuber M, Ritz R. How many patients with acute dissection of the thoracic aorta would erroneously receive thrombolytic therapy based on the electrocardiographic findings on admission? Am J Cardiol. 1993;72:1329-1330.