Navigating Misplaced Leads: A Case of Left Ventricle (LV) Lead Placement via a Patent Foramen Ovale (PFO) in a Dual-Chamber Permanent Pacemaker (PPM).

Pacemaker lead misplacement is a rare but clinically significant complication of pacemaker implantation. We present the case of a male patient in his 80s with a permanent pacemaker (PPM) who was found to have an inadvertently misplaced right ventricular (RV) lead coursing through a patent foramen ovale (PFO) into the left ventricle (LV). The patient presented with progressive dyspnoea and was found to have moderate mitral regurgitation related to lead interference with valve closure. Imaging modalities confirmed the lead's anomalous position. A multidisciplinary discussion concluded that conservative management with anticoagulation was the safest approach. This case highlights the importance of multimodal imaging in identifying lead misplacement and the clinical implications of inadvertent LV pacing. Furthermore, it underscores the importance of routine post-implantation assessment to detect lead displacement, which can often occur without symptoms. Early identification through systematic evaluation is essential to prevent complications and ensure optimal device function.