Dual Rare Lead-Related Complications

Abstract

Background

LMNA-related dilated cardiomyopathy is associated with ventricular remodeling and a high arrhythmic risk, frequently requiring implantable cardioverter-defibrillator (ICD) implantation. Although transvenous systems are generally safe, rare lead-related complications may occur.

Case Summary

We report a 51-year-old man with LMNA-related dilated cardiomyopathy who experienced 2 rare and sequential ICD lead complications. An initially septal right-ventricular lead was complicated by myocardial transfixion because of anterior apical positioning, revealed by cardiac computed tomography after a rise in pacing thresholds. During reintervention, a second lead was implanted but was later found to have traversed an unrecognized sinus venosus atrial septal defect with partial anomalous pulmonary venous return, resulting in inadvertent left-ventricular lead placement. The lead was successfully repositioned under transesophageal echocardiographic guidance. Three-dimensional computed tomography reconstruction clearly demonstrated both abnormal lead positions.

Discussion and Take-Home Message

This case highlights the importance of systematic troubleshooting, awareness of altered anatomy, and multimodality imaging during ICD implantation.

Visual Summary

Pathogenic truncating LMNA variants are associated with dilated cardiomyopathy, conduction disease, ventricular arrhythmias, and a high risk of sudden cardiac death, often warranting implantable cardioverter-defibrillator (ICD) implantation.1, 2, 3 Although transvenous systems are generally safe, rare complications such as myocardial perforation⁴ or inadvertent left-ventricular lead malposition^5,6 may occur and can be challenging to diagnose. We report a case in which both complications occurred sequentially in the same patient, underscoring important diagnostic and procedural challenges.

Visual Summary.

Dual Ventricular ICD Lead Malposition

(A) Lateral (left) chest radiographs show the dual-chamber implantable cardioverter-defibrillator system with the right ventricular defibrillation lead ($) projecting toward the RV apex and the atrial lead positioned in the right atrium. The abnormal anterior trajectory of the RV lead suggests a deviation from the expected septal course. The abnormal trajectory of the left ventricular lead (∗) shows an unintended course across an atrial septal defect and progression into the left ventricle (LV). (B and C) Three-dimensional computed tomography reconstruction of left lateral view (B) and 30° oblique view (C), with the right-sided chambers displayed in transparent blue, the left-sided chambers in transparent red, with the ventricular leads highlighted in yellow for the RV lead ($) and in green for the left ventricular lead (∗). Red open cycle in C shows the atrial septal defect.

History of Presentation, Past Medical History, and Differential Diagnosis

A 51-year-old man with genetically confirmed LMNA-related dilated cardiomyopathy (class 5 truncating variant in LMNA) was referred for primary prevention ICD implantation. Baseline imaging revealed markedly dilated left and right ventricles, with severe left ventricular systolic dysfunction (left ventricular ejection fraction: 30%). Coronary angiography had previously demonstrated normal coronary arteries.

A dual-chamber transvenous ICD was implanted. The right ventricular defibrillation lead was positioned on the apical septum with initially acceptable sensing, pacing thresholds, and impedances. However, within weeks, device interrogation demonstrated a significant increase in pacing thresholds after an internal shock for a ventricular tachycardia episode. A cardiac computed tomography (CT) scan subsequently revealed that the RV lead tip had perforated the myocardial wall, consistent with a lead perforation, without pericardial effusion, and demonstrated that the lead was in fact not septo-apical but positioned on the anterior wall of the RV.

Investigations and Management

The patient returned to the operating room for reintervention. Intraoperative testing showed absence of distal capture in unipolar configuration, supporting extracardiac positioning. The perforating lead was intentionally left in place (because there was no pericardial effusion and removal was considered to carry a risk of converting a contained perforation into cardiac tamponade) and a new RV lead was implanted. The second lead was targeted to the interventricular septum and appeared fluoroscopically satisfactory.

Unexpectedly, follow-up lateral chest radiographs raised concerns about unusual lead position. A repeat CT scan demonstrated that the new lead had traversed an unrecognized sinus venosus atrial septal defect (ASD) with partial anomalous right superior pulmonary venous connection; the lead crossed the interatrial septal defect via the triphasic ostium and entered the left atrium and ultimately advanced into the left ventricle (Figures 1 and 2). The lead tip was embedded in the inferolateral LV wall.

Figure 1.

Multiplanar Cardiac Computed Tomography Demonstrating Inadvertent Left Ventricular Lead Malposition Through a Sinus Venosus Atrial Septal Defect

Orientation markers are displayed on each image: A, anterior; P, posterior; R, right; I, inferior. (1) Sagittal reconstruction showing the ventricular lead crossing the interatrial septum through the sinus venosus atrial septal defect before entering the left atrium. (2) Axial reconstruction demonstrating the lead traversing the left atrium and mitral valve before reaching the left ventricle. (3) Coronal reconstruction illustrating the lead tip embedded in the lateral wall of the left ventricle. (4) Sagittal reconstruction illustrating the 2 ventricular leads in distinct ventricles.

Figure 2.

Intraoperative Transoesophageal Echocardiography Demonstrating Inadvertent Left Ventricular Lead Malposition Through a Sinus Venosus Atrial Septal Defect

(A) Aortic valve short-axis transoesophageal echocardiographic view confirming the lead traversing the posterior atrial septal defect before entering the left-sided cardiac chambers. (B) Bicaval transoesophageal echocardiographic view demonstrating the superior atrial septal defect with the ICD lead crossing the interatrial septum from the right atrium into the left atrium.

Outcome and Follow-up

The patient underwent a third procedure with intraoperative transesophageal echocardiographic guidance. The mispositioned lead was carefully retracted into the right atrium, redirected through the tricuspid valve, and successfully implanted on the true RV septum with appropriate electrical parameters.

Three-dimensional reconstruction of the cardiac CT provided a comprehensive visualization of both leads placed in the different ventricular cavities, illustrating the mechanism of these 2 rare complications.

Discussion

In this case, 2 uncommon ICD lead complications—myocardial transfixion and inadvertent left ventricular lead malposition into the LV through an unrecognized sinus venosus ASD—occurred sequentially in the same patient. To the best of our knowledge, no similar case has been reported. LMNA-related cardiomyopathy is characterized by progressive ventricular remodeling,⁷ frequently involving biventricular dilation and altered cardiac geometry, which may increase procedural complexity and predispose to lead-related complications during transvenous ICD implantation.⁸

Lead perforation is an uncommon but recognized complication (0.5% of implantations⁹), more frequent in patients with dilated ventricles, thin myocardial walls, or apical positioning.¹⁰ Sudden rises in pacing thresholds, abnormal lead impedances, or atypical lead orientation on imaging should prompt immediate evaluation, with cardiac CT being a highly sensitive modality.¹¹ In our case, the patient’s markedly dilated right ventricle had flattened the septum and altered cardiac orientation, creating the misleading impression on left anterior oblique fluoroscopy that the lead was correctly positioned on the apical septum. Previous studies have demonstrated that fluoroscopy alone has limited accuracy for determining true RV lead position, frequently misclassifying free-wall leads as septal when compared with cardiac CT.12, 13, 14 This limitation is particularly relevant in patients with altered cardiac geometry, such as the present case.

Unintentional LV lead placement, although rare, is clinically significant because of the risk of thromboembolism if unrecognized.¹⁵ It may occur via a patent foramen ovale, ASD, or arterial entry.⁶ In this case, a previously unknown sinus venosus ASD with partial anomalous pulmonary venous return created an atypical pathway facilitating LV malposition. This highlights the importance of suspecting congenital anomalies when fluoroscopic findings appear inconsistent with expected anatomy.

The combination of multimodality imaging—including echocardiography, fluoroscopy, and CT—was essential for both diagnosis and safe reintervention.

Conclusions

This case illustrates 2 rare and sequential ICD lead complications in a patient with LMNA-related dilated cardiomyopathy: anterior RV wall lead perforation followed by inadvertent LV lead malposition through an unrecognized sinus venosus ASD. The case emphasizes the importance of meticulous troubleshooting, awareness of potential congenital anomalies, and the role of multimodality imaging in guiding diagnosis and corrective interventions. The 3D CT reconstruction provides valuable teaching material for electrophysiologists facing similar scenarios.

Funding Support and Author Disclosures

The authors have reported that they have no relationships relevant to the contents of this paper to disclose.

Take-Home Messages

• •In patients with dilated cardiomyopathy, especially LMNA-related disease, altered cardiac geometry may lead to misleading fluoroscopic appearances and increase the risk of implantable cardioverter-defibrillator lead perforation or malposition, warranting a low threshold for advanced imaging and an increase in the incidence of standard fluorescent lighting.
• •Unexpected implantable cardioverter-defibrillator lead behavior should prompt consideration of underlying congenital anomalies, as unrecognized atrial septal defects may allow inadvertent left-ventricular lead placement with potentially serious consequences.