A 64-year-old man comes to the office due to shortness of breath for the last 6 months. He describes his lifestyle as active but says, "I can't catch my breath when I walk fast or climb the stairs. Six months ago, I felt completely fine." He has no symptoms at rest or at night, and he has had no palpitations, chest pain, lightheadedness, syncope, or lower extremity swelling. The patient has a history of hypertension and diet-controlled type 2 diabetes mellitus. He also takes over-the-counter antacid for occasional heartburn. He is a lifetime nonsmoker and drinks beer over the weekend. The patient has no family history of heart attacks or sudden cardiac death, but his grandfather had a stroke in his 60s. Blood pressure is 149/86 mm Hg and pulse is 88/min and regular. Oxygen saturation is 97% on room air. Lungs are clear on auscultation. No heart murmurs are heard. There is no peripheral edema. ECG shows normal sinus rhythm, voltage criteria for left ventricular hypertrophy, and T-wave inversion in leads V5 and V6. Creatinine is 0.9 mg/dL and complete blood count is unremarkable. Echocardiogram shows a dilated left ventricle with ejection fraction of 38%. Which of the following is the best next step in management of this patient?

Question

A 64-year-old man comes to the office due to shortness of breath for the last 6 months.  He describes his lifestyle as active but says, "I can't catch my breath when I walk fast or climb the stairs.  Six months ago, I felt completely fine."  He has no symptoms at rest or at night, and he has had no palpitations, chest pain, lightheadedness, syncope, or lower extremity swelling.  The patient has a history of hypertension and diet-controlled type 2 diabetes mellitus.  He also takes over-the-counter antacid for occasional heartburn.  He is a lifetime nonsmoker and drinks beer over the weekend.  The patient has no family history of heart attacks or sudden cardiac death, but his grandfather had a stroke in his 60s.  Blood pressure is 149/86 mm Hg and pulse is 88/min and regular.  Oxygen saturation is 97% on room air.  Lungs are clear on auscultation.  No heart murmurs are heard.  There is no peripheral edema.  ECG shows normal sinus rhythm, voltage criteria for left ventricular hypertrophy, and T-wave inversion in leads V5 and V6.  Creatinine is 0.9 mg/dL and complete blood count is unremarkable.  Echocardiogram shows a dilated left ventricle with ejection fraction of 38%.  Which of the following is the best next step in management of this patient?

Quizplus · Accepted Answer

Explanation: The progression of chronic heart failure is classified in 4 stages; this patient has Stage C heart failure with symptomatic left ventricular systolic dysfunction (ejection fraction <40%) due to dilated cardiomyopathy. Most cases of dilated cardiomyopathy are idiopathic (or primary), but coronary artery disease (CAD) leading to ischemic cardiomyopathy is the most common secondary etiology. Many patients with ischemic cardiomyopathy do not have typical anginal symptoms and initially present with symptoms of heart failure (eg, dyspnea, volume overload). Therefore, all patients with unexplained new-onset heart failure should be evaluated for CAD with stress testing or coronary angiography. Although acute myocardial infarction causes irreversible myocardial death, patients with chronic myocardial ischemia often have viable myocardial tissue with reversibly depressed contractility. In these patients, coronary revascularization can lead to improvement in symptoms, systolic function, and long-term mortality. Stage C heart failure (Choice A) Twenty-four-hour Holter monitoring is used to detect cardiac arrhythmia. Patients with persistent tachyarrhythmias can in rare cases develop dilated cardiomyopathy (tachycardia-mediated cardiomyopathy); however, this patient has not had symptoms (eg, palpitations, lightheadedness) to suggest tachyarrhythmia. (Choice B) Hypertension is a common secondary cause of dilated cardiomyopathy and should be managed aggressively with antihypertensive medication. This patient has a history of hypertension and may benefit from additional medication therapy, but ambulatory blood pressure monitoring will not be significantly helpful. (Choice C) Beta-natriuretic peptide levels can be used to differentiate heart failure exacerbation from other causes of dyspnea, and troponin levels are used for the detection of myocardial necrosis and infarction. These tests are typically more appropriate for evaluating acute symptoms rather than chronic progressive dyspnea, and are unlikely to influence management in this patient with known echocardiogram findings of dilated cardiomyopathy and left ventricular systolic dysfunction. (Choice E) Polysomnography is used to diagnose obstructive sleep apnea, which can indirectly contribute to the development of dilated cardiomyopathy by causing systemic hypertension. However, evaluation for CAD is more important for addressing this patient's heart failure. Educational objective: Coronary artery disease is the most common cause of secondary dilated cardiomyopathy, and evaluation with stress testing or coronary angiography should be performed in all patients presenting with unexplained heart failure due to left ventricular systolic dysfunction. References: Risk factors for congestive heart failure in US men and women: NHANES I epidemiologic follow-up study. (http://www.ncbi.nlm.nih.gov/pubmed/11295963) 2013 ACCF/AHA guideline for the management of heart failure: a report of the American College of Cardiology Foundation/American Heart Association Task Force on Practice Guidelines. (http://www.ncbi.nlm.nih.gov/pubmed/23747642)

A 64-Year-Old Man Comes to the Office Due to Shortness