Real-time CT-guided percutaneous placement of LV pacing leads.

OBJECTIVES

The aim of this study was to assess the feasibility of real-time computed tomographic (CT) imaging to guide the percutaneous placement of left ventricular (LV) leads in an animal model.

BACKGROUND

Cardiac resynchronization therapy has been shown to improve morbidity and mortality in patients with chronic heart failure. However, placement of the coronary sinus lead can be challenging and may require a more aggressive surgical approach.

METHODS

Nine swine were placed in a real-time CT scanner to define the safest percutaneous access strategy. Under real-time CT guidance, a 3.5-F pacing lead was placed percutaneously in the anterolateral LV epicardium (n = 6 swine) or to the posterolateral wall after the creation of intentional left pneumothorax (n = 3 swine) in a tangential (n = 12) or perpendicular (n = 1) approach. Pacing parameters and CT images were assessed during 30-min follow-up. Necropsy findings were compared with real-time CT images.

RESULTS

CT imaging successfully defined the safest percutaneous access route in all 13 lead placements and guided the therapeutic creation of pneumothoraces. Needle trajectory remained within 5 mm of the access route defined on CT imaging. LV lead placement under CT guidance was successful in all attempts within 19 ± 7 min. The mean pacing thresholds was 2.5 ± 1.5 V, the mean R wave amplitude was 11.2 ± 5.6 mV, and the mean impedance was 686 ± 103 Ω and remained unchanged after tangential placement during 30-min follow-up. Although no cardiac complications were observed with tangential lead placement (12 of 12), the perpendicular approach resulted in a pericardial effusion requiring pericardiocentesis. At necropsy, CT images correlated well with the in situ pathological results.

CONCLUSIONS

Percutaneous placement of LV pacing leads under CT guidance is feasible and might offer an alternative to more invasive surgical approaches in patients with complicated coronary sinus lead placement.