Abstract
Introduction
The left ventricular (LV) lead implantation in cardiac resynchronization therapy (CRT) is one of the most important and complex steps, leading to implantation failure in 10–15% of cases. New LV lead implantation techniques are needed to allow better resynchronization and decrease mortality and hospitalizations.
Objectives
To evaluate the efficacy and safety of the snare technique in the LV lead implantation in cases of standard technique failure.
Methods
Prospective, single-center study of patients undergoing CRT implantation since 2015. Demographic, clinical, and CRT implantation techniques were evaluated, taking into account the vessel with the best resynchronization capacity. The snare technique, through the active traction of the lead to the target vessel, was used in cases of standard technique failure. Time to surgical revision and mortality were evaluated by the Cox regression and Kaplan-Meier methods. Major complications, defined as reasons for prolonged hospitalization or potentially fatal, were evaluated.
Results
486 CRTs were implanted since 2015 (73.9% males, 73 years (IQR 66–79), median follow-up of 487 days (IQR 175–749), 91% for heart failure, dilated cardiomyopathy in 55.4%. In 17.3% of these patients (n=84), LV lead was implanted through the snare technique, 94% of the cases in a lateral vein, 100% efficacy in the positioning in the intended vessel.
Comparing the snare technique with the standard technique, patients implanted with snare presented a lower all-cause surgical revision (HR 0.31, 95% CI 0.094–0.98, p=0.035), with a number needed to treat of 25 patients to prevent one surgical revision, and a lower revision rate due to LV lead implant failure/dislodgement (Log Rank 5.1, p=0.024). There were no surgical revisions for LV lead repositioning in patients undergoing the snare technique. The rate of major complications (4.8% vs 3.0%, p=0.41), 30-day mortality (3.5% vs 1.8%, p=0.28) and all-cause mortality (13.1% vs 13.9%, p=0.47) were similar to the standard procedure. Major complications in both groups were pericardial effusion and contrast nephropathy.
The snare technique presented a longer procedure duration (104 vs 78 min, p<0.01) and fluoroscopy time (26.6 vs 15.5 min, p<0.01). Over time, there was a learning curve with reduction in procedure duration and fluoroscopy time.
Conclusion
The snare technique allows LV lead implantation in the vein with the best resynchronization characteristics, increasing the success rate in the implantation of CRT. It also reduced all-cause surgical revisions and surgical revisions due to LV lead implant failure/dislodgement, with a favourable safety profile similar to the standard technique.
Implantation Techniques of Leads for Left Ventricular Pacing in Cardiac Resynchronization Therapy and Electrocardiographic Consequences of the Stimulation Site