A 69-year-old man is brought to the emergency department due to severe chest pain that started suddenly, approximately 3 hours ago. He describes the pain as sharp and the "worst pain in my life." He feels the pain anteriorly as well as in his neck and between the shoulder blades. The patient has not seen a doctor for the past 20 years and takes no medications. On physical examination he appears very uncomfortable. There is an early diastolic decrescendo murmur at the right upper sternal border. ECG shows sinus tachycardia with nonspecific ST-segment and T-wave changes. Chest x-ray reveals widening of the superior mediastinum. Which of the following is the most likely predisposing condition in this patient?

Question

A 69-year-old man is brought to the emergency department due to severe chest pain that started suddenly, approximately 3 hours ago.  He describes the pain as sharp and the "worst pain in my life."  He feels the pain anteriorly as well as in his neck and between the shoulder blades.  The patient has not seen a doctor for the past 20 years and takes no medications.  On physical examination he appears very uncomfortable.  There is an early diastolic decrescendo murmur at the right upper sternal border.  ECG shows sinus tachycardia with nonspecific ST-segment and T-wave changes.  Chest x-ray reveals widening of the superior mediastinum.  Which of the following is the most likely predisposing condition in this patient?

Quizplus · Accepted Answer

11ec25c8_d32f_9374_bc81_d5215a325a95_MD0003_00 This patient's clinical presentation-sudden severe chest and back pain, early decrescendo diastolic murmur suggestive of aortic regurgitation (AR), widening of the mediastinum on chest x-ray, and nonspecific ST-segment and T-wave changes on ECG-is consistent with acute aortic dissection involving the ascending aorta, including extension into the aortic annulus (leading to acute AR). Chronic systemic hypertension is the most important predisposing risk factor for aortic dissection, present in >70% of cases. In addition to chronic hypertension, an acute and transient increase in blood pressure (eg, due to cocaine use or heavy lifting) is frequently noted as a precipitant of acute aortic dissection. Patients are usually older (age >60) and may have a prior aortic aneurysm. Atherosclerosis alone does not increase the predisposition to aortic dissection, although it is frequently present, particularly in association with thoracic aortic and abdominal aortic aneurysms (Choice C). (Choice A) Bicuspid aortic valve by itself may slightly increase the risk of aortic dissection; the association of bicuspid aortic valve with aortic root enlargement in some patients further increases the risk. However, systemic hypertension is a more significant predisposing factor. (Choices B and F) Deep venous thrombosis and rheumatic valvulitis are not associated with an increased risk of aortic dissection. (Choice D) Giant cell arteritis often presents with subacute systemic symptoms (eg, fever, weight loss), as well as headache, claudication, and vision changes. Aortic involvement can cause aneurysmal dilation and increase the risk of dissection; however, this is an uncommon complication. (Choice E) Marfan and Ehlers-Danlos syndromes are inherited connective tissue disorders characterized by degeneration and weakening of the medial layer of the aortic wall. Patients with these conditions have an increased risk for aortic aneurysm and aortic dissection. Although Marfan syndrome is responsible for almost 50% of the aortic dissections seen in patients age <40, it is an uncommon cause in older patients (age >60). Educational objective: Chronic systemic hypertension is the most important risk factor for aortic dissection, especially in older patients (age >60). Marfan syndrome is common in young patients (age <40) with aortic dissection, but it is rare in older patients with dissection. References: Risk profiles for aortic dissection and ruptured or surgically treated aneurysms: a prospective cohort study. (http://www.ncbi.nlm.nih.gov/pubmed/25609416) Corrigendum to: 2014 ESC guidelines on the diagnosis and treatment of aortic diseases. (http://www.ncbi.nlm.nih.gov/pubmed/26129948)

A 69-Year-Old Man Is Brought to the Emergency Department Due