A Rare Entrapment of Temporary Pacing Wire During Transcatheter Mitral Valve-in-Valve Procedure

Technical Summary: A Rare Entrapment of Temporary Pacing Wire During Transcatheter Mitral Valve-in-Valve Procedure

Problem Statement
Transcatheter mitral valve-in-valve (TM-ViV) implantation is a critical intervention for high-risk patients with degenerated surgical bioprosthetic valves. However, the procedure involves complex transseptal access and carries risks of periprocedural complications, including valve embolization, perforation, and conduction system injury. This case report addresses a rare and severe complication: the unintended malposition of a temporary pacing wire into the left ventricle via a patent foramen ovale (PFO), resulting in the wire becoming firmly entrapped between the existing surgical bioprosthesis and the newly deployed transcatheter valve. The clinical challenge lies in the prohibitive risk of extracting the wire, which could cause annular disruption, severe mitral regurgitation, or cardiac tamponade, particularly in an elderly patient with significant comorbidities.

Methodology and Case Management
The report details the management of an 89-year-old male with a degenerated mitral bioprosthesis and multiple comorbidities (heart failure, atrial fibrillation, renal insufficiency, hepatic cirrhosis) who underwent TM-ViV implantation using a 26-mm SAPIEN 3 valve.

• Procedural Setup: Under general anesthesia, a temporary pacing wire was positioned, presumed to be in the right ventricular apex. Transseptal puncture was performed under transesophageal echocardiographic (TEE) guidance, followed by balloon dilation and valve deployment under rapid ventricular pacing.
• Complication Identification: Post-deployment, resistance was encountered during wire withdrawal. Fluoroscopic imaging (LAO 45° and RAO 30° projections) revealed the wire had traversed the interatrial septum via a PFO, crossed the mitral orifice, and was entrapped between the stent frames of the two bioprosthetic valves.
• Conservative Strategy: Given the high surgical risk and the danger of percutaneous extraction, a multidisciplinary team decided against removal. The wire was transected approximately 2 cm from the venous access site, and the retained intracardiac segment was buried subcutaneously.
• Post-Procedural Care: The patient was placed on long-term warfarin anticoagulation (target INR 2.5–3.5) to mitigate thromboembolic risks associated with the retained foreign body.

Key Results

• Immediate Outcome: The TM-ViV procedure was successful with a reduction in mean transvalvular gradient from 22 mmHg to 4 mmHg, no paravalvular regurgitation, and satisfactory valve positioning.
• Follow-up: At the 12-month follow-up, the patient exhibited significant improvement in cardiac functional status and alleviation of dyspnea. Serial echocardiograms confirmed the continued satisfactory function of the new bioprosthesis.
• Safety Profile: No thromboembolic events (transient ischemic attacks, stroke, systemic embolism), infective endocarditis, or bleeding complications were observed during the one-year period.

Key Contributions
This case report provides the first documented instance of temporary pacing wire entrapment specifically following a TM-ViV implantation. It contributes to the literature by:

1. Documenting a Unique Complication: Highlighting the specific mechanism of wire malposition through a PFO into the left ventricle and subsequent entrapment between bioprosthetic valves.
2. Validating a Conservative Management Approach: Demonstrating that wire transection with subcutaneous burial, combined with chronic anticoagulation, is a viable and safe alternative when extraction poses excessive risk.
3. Identifying Diagnostic Gaps: The case underscores that reliance on bedside telemetry without specific lead monitoring (e.g., V1) and the absence of routine TEE monitoring during wire placement can lead to delayed detection of malposition.

Significance and Claims
The authors assert that this case demonstrates conservative management is a safe and effective alternative for complicated wire entrapment where extraction is contraindicated. The report emphasizes the critical importance of vigilant real-time monitoring of the pacing wire course during transseptal structural heart interventions. Specifically, it advocates for the use of dual-plane fluoroscopy (LAO and RAO) and electrocardiographic morphology analysis (looking for right bundle branch block patterns indicative of left ventricular pacing) to prevent such malpositions. The paper concludes that while the complication is serious, it is preventable through heightened vigilance and standard procedural techniques in structural heart interventions.