A 66-year-old retired police officer is brought to the emergency department due to abrupt-onset sharp anterior chest pain. The pain started approximately 2 hours ago while he was working on his car in the garage. The patient describes the pain, which radiates to his neck and lower jaw, as "the worst pain of my life." He also has epigastric discomfort. Medical problems include hypertension, hyperlipidemia, and benign prostatic hyperplasia. Medications include hydrochlorothiazide, losartan, tamsulosin, atorvastatin, and daily aspirin. The patient has a 30-pack-year smoking history but quit approximately 5 years ago. He is physically active and jogs 2-3 miles on most days.
Temperature is 37.2 C (99 F), blood pressure is 201/104 mm Hg in the right upper arm and 198/94 mm Hg in the left upper arm, pulse is 90/min, and respirations are 22/min. Pulse oximetry is 95% on room air. The patient appears very uncomfortable due to pain. There is a faint early diastolic murmur at the left sternal border and an S4 at the apex. The lungs are clear to auscultation. Mild epigastric tenderness is present on deep palpation without rebound. There is no peripheral edema, and lower extremity pulses are symmetric.
ECG shows high-voltage QRS complexes in the precordial leads and nonspecific ST-segment and T-wave changes.
Which of the following is the most appropriate initial treatment for this patient?

Question

A 66-year-old retired police officer is brought to the emergency department due to abrupt-onset sharp anterior chest pain.  The pain started approximately 2 hours ago while he was working on his car in the garage.  The patient describes the pain, which radiates to his neck and lower jaw, as "the worst pain of my life."  He also has epigastric discomfort.  Medical problems include hypertension, hyperlipidemia, and benign prostatic hyperplasia.  Medications include hydrochlorothiazide, losartan, tamsulosin, atorvastatin, and daily aspirin.  The patient has a 30-pack-year smoking history but quit approximately 5 years ago.  He is physically active and jogs 2-3 miles on most days.
Temperature is 37.2 C (99 F), blood pressure is 201/104 mm Hg in the right upper arm and 198/94 mm Hg in the left upper arm, pulse is 90/min, and respirations are 22/min.  Pulse oximetry is 95% on room air.  The patient appears very uncomfortable due to pain.  There is a faint early diastolic murmur at the left sternal border and an S4 at the apex.  The lungs are clear to auscultation.  Mild epigastric tenderness is present on deep palpation without rebound.  There is no peripheral edema, and lower extremity pulses are symmetric.
ECG shows high-voltage QRS complexes in the precordial leads and nonspecific ST-segment and T-wave changes.
Which of the following is the most appropriate initial treatment for this patient?

Quizplus · Accepted Answer

11ec193a_95ca_1933_853d_9f6ce1208bae_MD0002_00 The abrupt onset of sharp, severe chest pain in this patient with evidence of long-standing hypertension (ie, audible S4, high-voltage QRS complexes suggesting left ventricular [LV] hypertrophy) and a murmur of acute aortic regurgitation (decrescendo diastolic murmur) strongly suggests acute aortic dissection. A pulse deficit or significant systolic blood pressure (SBP) difference (>20 mm Hg) between extremities is absent in approximately two-thirds of presenting patients. In addition to pain control, initial therapeutic goals for suspected aortic dissection include lowering SBP to ≤120 mm Hg and decreasing LV contractility to reduce aortic wall shear stress. Drugs that decrease the rate of rise in systolic pressure with each ventricular contraction (dp/dt) are optimal for the initial treatment of aortic dissection. Intravenous beta blockers (eg, labetalol, propranolol, esmolol) are preferred in this setting to reduce both blood pressure and LV contractility. (Choices A and E) Antiplatelet agents (eg, clopidogrel) and unfractionated heparin are appropriate therapy for acute coronary syndrome; however, the sharp character of this patient's chest pain is atypical for cardiac chest pain, and ECG shows no definitive evidence of ischemia. These drugs are likely to cause further propagation of an acute aortic dissection (eg, resulting in hemothorax or hemopericardium) and are contraindicated when the diagnosis is suspected. (Choice B) Hydralazine is a direct arterial vasodilator that can cause reflex sympathetic stimulation, leading to increased heart rate, LV contractility, and aortic wall shear stress. As a result, its use should be avoided in patients with suspected aortic dissection. (Choice D) Nitroprusside is also a potent vasodilator that can cause reflex sympathetic stimulation; however, due to a short half-life and relative ease in titration, it is the preferred drug for additional blood pressure control in patients with acute aortic dissection who have persistent SBP elevation despite initial antihypertensive therapy. In such patients, nitroprusside (typically administered for SBP >120 mm Hg) should be given only after adequate beta blockade due to the risk of reflex sympathetic stimulation. Educational objective: Dissection involving the ascending aorta can result in acute aortic regurgitation (evidenced by a decrescendo diastolic murmur). Intravenous beta blockers are preferred in patients with suspected aortic dissection to lower blood pressure and decrease left ventricular contractility to reduce aortic wall shear stress. Nitroprusside should be given only following adequate beta blockade. __________ References: Presentation, diagnosis, and outcomes of acute aortic dissection: 17-year trends from the International Registry of Acute Aortic Dissection. (http://www.ncbi.nlm.nih.gov/pubmed/26205591) 2010 ACCF/AHA/AATS/ACR/ASA/SCA/SCAI/SIR/STS/SVM guidelines for the diagnosis and management of patients with thoracic aortic disease. (http://www.ncbi.nlm.nih.gov/pubmed/20233780)

A 66-Year-Old Retired Police Officer Is Brought to the Emergency