Permanent Pacemaker Implantation in Patients With Isolated Persistent Left Superior Vena Cava From a Right-Sided Approach: Technical Considerations and Follow-Up Outcome.

BACKGROUND: Positioning a permanent pacing wire in patients with persistent left superior vena cava (PLSVC) to right ventricle often comes as on-table surprise. It is technically demanding and therefore most of operators prefer left-sided approach. We assessed technical challenges during pacemaker implantation, and their short- and long-term outcomes among patients with isolated PLSVC from a right-sided approach.

METHODS: Thirty-one consecutive patients with isolated PLSVC and 93 patients with right superior vena cava (RSVC) were enrolled with syncope with sinus node dysfunction (SND) and atrioventricular (AV) block. Study was designed on the basis of nested case-control method, and therefore 1:3 proportions was the enrolment criteria to detect any difference as statistically significant as incidence of isolated PLSVC is low.

RESULTS: Mean age of patients was 64.8 ± 10.5 years. SND was the most common indication (n = 55; 44%) followed by AV block (n = 47; 37%). Nineteen (20%) patients received tined pacing lead, while 105 (85%) had screwing lead. There was no significant difference in mean procedural time (25 ± 11 min vs. 23 ± 12 min; P = 0.24), mean fluoroscopic time (3.1 ± 2.2 min vs. 2.7 ± 2.1 min; P = 0.54), pacing parameters for atrial and ventricular leads, dislodgement rate (3.2% vs. 4.8%; P = 0.32) and follow-up duration (6.9 ± 1.3 years vs. 7.2 ± 1.1 years; P = 0.18) between two groups. Compared to patients with RSVC, those with PLSVC had alpha loop configuration for ventricular lead which was statistically significant (31 vs. 00; P = 0.002).

CONCLUSIONS: Patients with PLSVC had alpha loop configuration for ventricular lead because of circuitous course via left mediastinum. Although pacemaker implantation through coronary sinus via isolated PLSVC from right sided-approach is technically challenging, it obtains good long-term results but needs frequent follow-up during the initial period.