A 79-Year-Old Woman With a Pacemaker and High Atrial Rates

Jeff S. Healey, MD, MSc, FRCPC; Jonathan P. Piccini, MD, MHS, FACC; Christian T. Ruff, MD, MPH


March 22, 2019

Editorial Collaboration

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A 79-year-old woman presents for her annual pacemaker follow-up. She has a history of hypertension over the past 20 years, which is currently well controlled on perindopril (8 mg daily). She has no other significant medical or surgical history, no known allergies, and no history of bleeding. Ten years ago she had some transient lightheadedness and was diagnosed in the emergency room with a possible transient ischemic attack. A follow-up visit with a neurologist did not reveal any neurologic deficit, and an MRI of the brain revealed a small, old lacunar infarct in the basal ganglia that did not correlate with her symptoms. Her echocardiogram revealed mild left ventricular hypertrophy and mild left atrial enlargement.

Eight years ago the patient presented with a more profound episode of lightheadedness and had a syncopal episode while in the emergency room. The cardiac monitor revealed paroxysmal high-grade atrioventricular (AV) block. She then underwent implantation of a dual-chamber pacemaker, and her symptoms have not recurred. Her pacemaker and leads continue to function as expected. At this year's visit, she is found for the first time to have short-lasting, asymptomatic atrial high-rate episodes (Figure 1).

Figure 1.


She does not report palpitations, shortness of breath upon exertion, chest pain, or recurrent syncope. She does not appear to have had any further neurologic events. She denies any other symptoms and has not sought medical attention for any issues since her last visit.


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