Atrial Lead Dislodgement in Dual-Chamber Permanent Pacemaker​

An 88-year-old male status post dual-lead permanent pacemaker placement presented with symptoms of pacemaker malfunction, including bradycardia and fatigue. What is the diagnosis? • Xray of the Week

Figure 1. Frontal chest X-ray. What is the diagnosis?

Figure 2. Frontal chest X-ray: Both pacemaker leads project over the right ventricle (red and green arrows), with the intended atrial lead dislodged from the right atrium and positioned in the right ventricle alongside the ventricular lead. The pulse generator is appropriately located in the left pectoral region.

Diagnosis

Atrial lead dislodgement in dual-lead permanent pacemaker, with both leads in the right ventricle.

Discussion

Pacemaker lead dislodgement is a common early complication of dual-lead permanent pacemaker implantation, occurring in 1-5% of cases, often due to inadequate fixation, patient activity, or twiddler's syndrome (patient manipulation of the device).[1][2] In dual-lead systems, the atrial lead is typically placed in the right atrial appendage for sensing and pacing, while the ventricular lead is in the right ventricular apex. Dislodgement of the atrial lead into the right ventricle can lead to ineffective atrial pacing, loss of atrioventricular synchrony, and symptoms of pacemaker syndrome or arrhythmia.[3][4]

Radiologically, this manifests as abnormal lead trajectory on chest X-ray, potentially causing complications like perforation, thrombosis, or tricuspid valve injury if unrecognized.[5]

Imaging Findings

Chest X-ray is the first-line modality for assessing pacemaker lead position and integrity post-implantation, with high sensitivity for detecting dislodgement (nearly 100% when compared to electrocardiography).[1][6] Frontal and lateral views are essential; lateral views help confirm chamber placement, as frontal views alone may be ambiguous due to overlap.

• On frontal chest X-ray: The normal atrial lead shows a gentle J-curve toward the right atrium (superior and lateral), while the ventricular lead has a straighter course to the right ventricular apex (inferior and medial). In dislodgement, the atrial lead deviates inferiorly, projecting over the right ventricle similar to the ventricular lead, often appearing parallel or crossed.

• Associated findings: Lead redundancy, coiling, or fracture; pulse generator rotation (in twiddler's syndrome); or signs of perforation (e.g., lead tip beyond cardiac silhouette).

Multiplanar CT can be used for confirmation if X-ray is equivocal, but routine post-implantation chest X-ray is sufficient for most cases.[2][7]

Lead Type	Normal Position on Frontal Chest X-ray	Abnormal (Dislodged) Position
Atrial Lead	J-shaped curve directing superior-laterally to right atrial appendage	Straight or inferior course to right ventricle, parallel to ventricular lead
Ventricular Lead	Straight course to right ventricular apex, tip pointing inferior-medially	May be unaffected, but both leads in RV if atrial dislodged

Management and Prognosis

Management involves urgent lead repositioning via percutaneous extraction and reimplantation, with electrocardiographic confirmation of capture; anticoagulation may be needed if thrombosis is suspected.[3][5] Prognosis is excellent with early detection (success rate >95%), but delayed recognition can lead to reoperation or complications like heart failure (mortality <1% in uncomplicated cases).[4][6]

Key Learning Points

• Chest X-ray is critical for immediate post-implantation evaluation of pacemaker lead position, identifying dislodgement by abnormal trajectory.

• Look for lack of J-curve in the atrial lead and both leads projecting over the right ventricle on frontal views; obtain lateral views to confirm chamber.

• Radiology interpretation guides timely intervention, preventing complications like perforation or loss of pacing—always compare to prior films.

• Routine chest X-ray post-procedure detects most lead-related issues; correlate with ECG for functional assessment.

References

1. Costelloe CM. Radiography of pacemakers and implantable cardioverter defibrillators. AJR Am J Roentgenol. 2012;199(6):1252-1258. doi:10.2214/AJR.12.8641

2. Silva C, Christensen JD. How I do it: evaluating cardiac implantable devices and noncardiac mimics on chest radiographs. Radiology. 2025;315(2):e241911. doi:10.1148/radiol.241911

3. Hunter TB, Taljanovic MS, Tsau PH, Berger WG, Standen JR. Medical devices of the chest. Radiographics. 2004;24(6):1725-1746. doi:10.1148/rg.246045031

4. Aguilera AL, Volokhina YV, Fisher KL. Radiography of cardiac conduction devices: a comprehensive review. Radiographics. 2011;31(6):1669-1682. doi:10.1148/rg.316115529

5. Dipoce J, Soni A, Dhillon S, Golzarian J. Radiology of cardiac devices and their complications. Br J Radiol. 2015;88(1046):20140540. doi:10.1259/bjr.20140540

6. Pascual Alandete Germán S, Isarria Vidal S, Domingo Montañana ML, De la Vía Oraá E, Vilar Samper J. Pacemakers and implantable cardioverter defibrillators, unknown to chest radiography: review, complications and systematic reading. Eur J Radiol. 2015;84(3):499-508. doi:10.1016/j.ejrad.2014.12.011

7. Mathew RP, Alexander T, Patel V, Low G. Chest radiographs of cardiac devices (Part 1): cardiovascular implantable electronic devices, cardiac valve prostheses and Amplatzer occluder devices. SA J Radiol. 2019;23(1):1730. doi:10.4102/sajr.v23i1.1730

Kevin M. Rice, MD is the president of Global Radiology CME and is a radiologist with Cape Radiology Group. He has held several leadership positions including Board Member and Chief of Staff at Valley Presbyterian Hospital in Los Angeles, California. Dr. Rice has made several media appearances as part of his ongoing commitment to public education. Dr. Rice's passion for state-of-the-art radiology and teaching includes acting as a guest lecturer at UCLA. In 2015, Dr. Rice and Natalie Rice founded Global Radiology CME to provide innovative radiology education at exciting international destinations, with the world's foremost authorities in their field. In 2016, Dr. Rice was nominated and became a semifinalist for a "Minnie" Award for the Most Effective Radiology Educator. He was once again a semifinalist for a "Minnie" for 2021's Most Effective Radiology Educator by AuntMinnie.com. He has continued to teach by mentoring medical students interested in radiology. Everyone he has mentored has been accepted into top programs across the country, including Harvard, UC San Diego, Northwestern, Vanderbilt, and Thomas Jefferson.

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