ECG of the Month: A 76-Year-Old Woman Presents with Frequent PVC
A 76-year-old woman with a history of hypertension and known left bundle branch block (LBBB) is admitted for new-onset atrial fibrillation (Figure 1A) and heart failure. Echocardiography demonstrates global left ventricular hypokinesis with moderately depressed left ventricular systolic function, suggesting tachycardia induced cardiomyopathy. A direct current cardioversion is attempted, but is unsuccessful. She is started on dofetilide 500 mcg twice daily, dose adjusted given her creatinine clearance is reduced. She is continued on diltiazem, furosemide, and digoxin. No significant QT prolongation is noted after two doses of dofetilide. An arrhythmia is recorded on telemetry at 2:00 a.m. (Figure 1B).
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