51-Year-Old With Dyspnea and Palpitations

Case Presentation

51-year-old female with hypertrophic cardiomyopathy and a history of recurrent AF for which she began taking amiodarone 200 mg PO daily 18 months ago. Mild hypothyroidism was noted 3 months after starting amiodarone, and a small dose of synthroid was prescribed and amiodarone was continued.

51-Year-Old With Dyspnea and Palpitations
Other pertinent medical history includes sinoatrial node dysfunction for which a dual chamber pacemaker was implanted in 1999.

At her last visit to clinic several months earlier, she had no complaints, and pacemaker interrogation revealed normal device function with minimal atrial fibrillation. She now presents to the hospital emergency department with dyspnea, lower extremity edema and palpitations. In addition she complains of an unintentional 10 pound weight loss and GI irritability over the past month.


Amiodarone 200 mg daily
Synthroid 50 mcg daily
diltiazem 240 mg daily
Lasix 40 mg daily
warfarin to maintain INR 2.0 – 3.0.

Physical Exam

VS: HR 126, BP 138/62, RR 14, Afebrile 98% on 2 L

Gen: Alert, slightly anxious, does not appear dyspneic

Neck: 12 cm JVP Lungs-Bibasilar crackles CV-Irregularly Irregular, Brisk pulses, 2/6 SEM LUSB Abdomen-Benign, no masses

Extremities: Warm, 2+ Pitting Edema

Neurologic Exam: Normal

Laboratory Values (provide ranges)

Hgb: 12.6 (12.9 – 16.9 g/dl)
Platelets: 274 (150 – 350 x103/ul)
WBC: 9.3 (4.5 – 11 x103/ul)
Troponin I: 0.10 (0.00 – 0.09 ng/ml)
Serum Creatinine: 0.9 (0.6 – 1.5 mg/dl)
Potassium: 4.1 (3.4 – 4.8 mEq/L)
Magnesium: 2.2 (1.4 – 2.0 mg/dl)
NT-Pro BNP: 14,500 (0 – 900 pg/dl)

Based on the above information, the next best step in evaluation would be:

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