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A 65-year-old man presented with an acute onset of aphasia for which he received intravenous thrombolysis with substantial improvement. This was the second stroke he had in 6 months. The patient’s other medical problems included well-controlled hypertension and diabetes. Seven months before this admission, a dual-chamber pacemaker was implanted at an outside institution for sick sinus syndrome. Device interrogation revealed no atrial fibrillation and normal lead parameters. Electrocardiogram results showed atrial pacing with capture and intrinsic ventricular conduction. Magnetic resonance angiography results of carotid, vertebral, and cerebral arteries were normal. Chest radiography was taken (Figure 1).
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Mispositioned lead in the left ventricle through an atrial septal defect
A. Transthoracic echocardiogram
On the posterior-anterior projection (Figure 1A), the ventricular lead curves more superiorly than usual and lacks the expected indentation as it traverses the tricuspid valve. The lateral projection (Figure 1B) demonstrates a posterior orientation of the lead that is suspicious of left ventricular placement. A correctly placed right ventricular lead courses more laterally in the right atrium, is closer to the inferior border of the cardiac silhouette, and points anteriorly on the lateral radiograph. Dynamic tenting of the lead by the tricuspid annulus in systole can be visualized on fluoroscopy. A right-bundle branch block pattern of depolarization is another indicator of lead malposition but was not present in this patient because of intrinsic conduction.
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Corresponding Author: Shing Ching, MBBS, Division of Cardiology, Department of Medicine and Geriatrics, United Christian Hospital, Hip Wo St, Kwun Tong, Kowloon, Hong Kong, China (firstname.lastname@example.org).
Published Online: October 30, 2019. doi:10.1001/jamacardio.2019.4140
Conflict of Interest Disclosures: None reported.
Additional Contributions: We thank the patient for granting permission to publish this information.
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