A 50-year-old woman comes to the office after 4 weeks of nonproductive cough. The cough is constant throughout the day and "very annoying." The patient was diagnosed with nonischemic cardiomyopathy 2 months ago when she was hospitalized with shortness of breath and lower extremity edema. She reports marked improvement with breathing and no nighttime awakenings. The patient has no fever, sore throat, rhinorrhea, chest pain, or hemoptysis. Medications include carvedilol, lisinopril, spironolactone, and torsemide. The patient smoked cigarettes from age 25-30, and she does not use alcohol or illicit drugs. Her temperature is 36.7 C (98 F), pulse is 78/min, blood pressure is 132/74 mm Hg, and respirations are 14/min. BMI is 32 kg/m². The patient's oropharynx is clear, jugular veins are flat when she is supine, lungs are clear on auscultation, and no peripheral edema is present. A faint systolic murmur is heard at the apex. Chest x-ray reveals mild cardiomegaly and clear lung fields. Which of the following is the best next step in managing this patient's current symptoms?

Question

Quizplus · Accepted Answer

The chronic nonproductive cough in this patient with heart failure is likely an adverse effect of ACE inhibitor therapy. ACE inhibitors (eg, lisinopril) cause cough in up to 20% of patients, and onset of the cough is typically within a week of drug initiation or dosage increase (although onset may be delayed for months). The pathogenesis of the cough is likely related to an increase in the circulating levels of inflammatory mediators (eg, bradykinin, substance P, thromboxane, prostaglandins) that results in bronchoconstriction and bronchial irritation. (Choice A) CT scan of the chest is more sensitive than chest x-ray in ruling out lung malignancy as the etiology of chronic cough; however, it is not indicated in this patient with a minimal, remote smoking history and an absence of weight loss, chest pain, and hemoptysis. CT scan should be considered if the cough persists following discontinuation of lisinopril. (Choice C) Torsemide does not have a strong association with cough, and discontinuation may lead to volume overload and an acute heart failure exacerbation in this patient. (Choices D and F) Asthma, a common cause of chronic cough, is diagnosed with pulmonary function testing and treated with an albuterol inhaler. However, onset of symptoms in middle adulthood and absence of wheezing are not typical of asthma and make the diagnosis unlikely. (Choice E) A serum brain natriuretic peptide level <100 pg/mL is useful in ruling out a suspected heart failure exacerbation. However, this patient has no evidence of such an exacerbation (eg, crackles on lung auscultation, lower extremity swelling, jugular venous distension, shortness of breath). Cough due to heart failure is typically productive rather than nonproductive. (Choice G) The anticholinergic effect of oral antihistamine (eg, diphenhydramine) is useful in treating chronic cough due to upper airway cough syndrome (postnasal drip), which is unlikely in the absence of rhinorrhea. Educational objective: ACE inhibitors commonly cause chronic cough and should be considered in the differential diagnosis in all patients taking the medication. References: Differential diagnosis of chronic cough. (http://www.ncbi.nlm.nih.gov/pubmed/16450567)

A 50-Year-Old Woman Comes to the Office After 4 Weeks