A 32-year-old man is evaluated for syncope. The patient passed out once briefly when playing basketball and experienced no post-syncopal symptoms. Over the last year, he has tired easily and becomes short of breath when climbing 3-4 flights of stairs. The patient takes lansoprazole for acid reflux. In the past, a physician had told him that his blood pressure is "borderline." The patient smokes half a pack of cigarettes a day. His paternal uncle died suddenly at age 30. Blood pressure is 152/90 mm Hg and pulse is 90/min. A 2/6 midsystolic murmur is heard at the left sternal border and accentuates on standing. Lungs are clear to auscultation. Echocardiography shows left atrial enlargement, interventricular septal thickness of 2 cm (normal

Question

A 32-year-old man is evaluated for syncope.  The patient passed out once briefly when playing basketball and experienced no post-syncopal symptoms.  Over the last year, he has tired easily and becomes short of breath when climbing 3-4 flights of stairs.  The patient takes lansoprazole for acid reflux.  In the past, a physician had told him that his blood pressure is "borderline."  The patient smokes half a pack of cigarettes a day.  His paternal uncle died suddenly at age 30.  Blood pressure is 152/90 mm Hg and pulse is 90/min.  A 2/6 midsystolic murmur is heard at the left sternal border and accentuates on standing.  Lungs are clear to auscultation.  Echocardiography shows left atrial enlargement, interventricular septal thickness of 2 cm (normal <1.1 cm), and posterior left ventricular wall thickness of 0.9 cm (normal <1.1 cm).  Left ventricular ejection fraction is 75%.  There is systolic anterior motion of the mitral valve.  At rest, peak instantaneous left ventricular outflow gradient is 30 mm Hg and increases to 45 mm Hg with Valsalva.  Which of the following is the most appropriate next step in management of this patient?

Quizplus · Accepted Answer

Explanation: 11ec2b69_be2e_7a7d_8f63_d1799331684e_MD0005_00 This patient's clinical history-fatigue, dyspnea, exertional syncope, and family history of sudden cardiac death (SCD)-along with physical examination and echocardiographic findings, is consistent with hypertrophic cardiomyopathy (HCM). HCM is an autosomal dominant genetic disorder of the cardiac sarcomere with a heterogeneous and variable clinical presentation. SCD is the most dreaded complication of HCM, with an annual incidence of approximately 1%. Implantable cardioverter-defibrillator (ICD) placement is indicated for prevention of SCD in patients with a history of cardiac arrest or sustained, spontaneous ventricular tachycardia (VT). Patients with HCM who are at high risk for malignant arrhythmias (eg, family history of SCD, recurrent or exertional syncope, nonsustained VT, hypotension with exercise, extreme left ventricular hypertrophy) should also be considered for ICD placement. This patient has a history of syncope during exertion and a family history of SCD and should be referred for an ICD placement to prevent SCD. (Choice A) Alcohol septal ablation is usually reserved for patients with persistent symptoms refractory to medical therapy. Alcohol septal ablation is not indicated for prevention of SCD in patients with HCM, and in fact may increase the risk for SCD or VT. (Choice B) Lisinopril and other vasodilators cause a reduction in systemic vascular resistance, potentially worsening the left ventricular outflow tract gradient in patients with HCM. Beta blockers are considered first-line treatment for hypertension in patients with HCM. (Choice D) A moderate weight loss program may be recommended in patients with HCM who have been treated adequately. However, intensive weight loss is not advised as it may be associated with an increased risk for SCD. (Choice E) Tilt table testing is indicated in patients with recurrent episodes of syncope but no evidence of structural heart disease. This patient has HCM with high-risk features and should have an ICD placed for primary prevention of SCD. Educational objective: Implantable cardioverter-defibrillator placement is indicated for preventing sudden cardiac death (SCD) in patients who have hypertrophic cardiomyopathy and an increased risk for SCD due to: Prior history of cardiac arrest or sustained, spontaneous ventricular tachycardia (VT) Family history of sudden death Recurrent or exertional syncope Nonsustained VT Hypotension with exercise Extreme left ventricular hypertrophy References: Implantable defibrillators and prevention of sudden death in hypertrophic cardiomyopathy. (http://www.ncbi.nlm.nih.gov/pubmed/18384577)

A 32-Year-Old Man Is Evaluated for Syncope