A 48-year-old man comes to the emergency department due to severe chest pain that started 2 hours ago. He has difficulty localizing the pain, saying that it "hurts all over my chest." He has had no shortness of breath, lightheadedness, syncope, or palpitations. The patient has no known medical conditions. He is a lifetime nonsmoker and does not use illicit drugs. His father died suddenly at age 52 from a presumed heart attack. Temperature is 36.7 C (98.1 F), blood pressure is 178/102 mm Hg, pulse is 105/min and regular, and respirations are 16/min. On physical examination, the lungs are clear to auscultation and heart sounds are normal. ECG reveals sinus tachycardia, voltage criteria for left ventricular hypertrophy, and T-wave inversion in leads V5 and V6. A CT image of the chest is shown below. In addition to pain control, which of the following is the most appropriate, immediate pharmacotherapy for this patient?

Question

A 48-year-old man comes to the emergency department due to severe chest pain that started 2 hours ago.  He has difficulty localizing the pain, saying that it "hurts all over my chest."  He has had no shortness of breath, lightheadedness, syncope, or palpitations.  The patient has no known medical conditions.  He is a lifetime nonsmoker and does not use illicit drugs.  His father died suddenly at age 52 from a presumed heart attack.  Temperature is 36.7 C (98.1 F), blood pressure is 178/102 mm Hg, pulse is 105/min and regular, and respirations are 16/min.  On physical examination, the lungs are clear to auscultation and heart sounds are normal.  ECG reveals sinus tachycardia, voltage criteria for left ventricular hypertrophy, and T-wave inversion in leads V5 and V6.  A CT image of the chest is shown below.  In addition to pain control, which of the following is the most appropriate, immediate pharmacotherapy for this patient?

Quizplus · Accepted Answer

Explanation: 11ec25c8_d176_235a_bc81_d78c4165aa52_MD0003_00 This patient's clinical presentation and CT scan findings (intimal tears separating the true and false lumens of the ascending and descending aorta) are consistent with aortic dissection. Aortic dissection involving the ascending aorta (type A) is considered a surgical emergency, with mortality rates of 1%-2% per hour following symptom onset; rapid diagnosis and treatment are critical. CT scan findings type A The goals of initial therapy of aortic dissection include: adequate pain control. reduction of systolic blood pressure (SBP) to 100-120 mm Hg. decrease in left ventricular (LV) contractility to reduce aortic wall stress. Intravenous beta blockers (eg, labetalol, propranolol, esmolol) are preferred for initial therapy to reduce heart rate, SBP, and LV contractility. These effects lead to a decrease in the rate of rise in SBP (dP/dt) and in aortic wall stress. (Choice A) Aortic dissection, especially involving the aortic root, can cause acute aortic regurgitation, which can lead to acute heart failure and pulmonary edema requiring diuretic (eg, furosemide) therapy. This patient's lungs are clear, making pulmonary edema unlikely; therefore, diuretics would have no role in management. (Choices B and D) Hydralazine and nitroprusside are vasodilators sometimes used in hypertensive emergencies. However, they can cause reflex sympathetic stimulation with consequent rises in heart rate, LV contractility, and aortic wall stress. These changes increase the risk of propagation of an aortic dissection. In patients with aortic dissection, nitroprusside is used as a second-line agent only if SBP remains above goal (ie, >120 mm Hg) despite adequate beta blockade. (Choices E and F) Patients with aortic dissection should not receive thrombolytic therapy with tissue plasminogen activator (appropriate in some patients with ischemic stroke) or anticoagulation therapy with intravenous heparin (appropriate in some patients with acute coronary syndrome or pulmonary embolism) due to the risks of bleeding and propagation of the dissection into the pericardial space (hemopericardium). Educational objective: Intravenous beta blockers (eg, labetalol, esmolol) are the treatment of choice for the initial medical management of patients with acute aortic dissection, as they lower heart rate and blood pressure and reduce left ventricular contractility. References: Diagnosis and management of aortic dissection. (http://www.ncbi.nlm.nih.gov/pubmed/11511117) Acute aortic syndromes. (http://www.ncbi.nlm.nih.gov/pubmed/16344407)

A 48-Year-Old Man Comes to the Emergency Department Due to Severe