Introduction

We report a case of a successful His-Bundle Pacing in the presence of an isolated PLSVC. 

Case

A 72-year-old male with a history of symptomatic sick sinus syndrome, and mild left ventricular nonischemic cardiomyopathy presented with New York Heart Association (NYHA) class III heart failure symptoms and had an ejection fraction of 45% to 50% despite optimal guidelines-directed neurohormonal blockade. As the patient had a normal QRS complex, with a wide first degree AV-Block (PQ > 300ms, Figure 1) a His-bundle pacing approach was chosen in order to achieve rate control and maintain physiologic activation of the ventricles.

After obtaining left subclavian access a venography showed an isolated PLSVC with dilated coronary sinus. A stearable sheat was introduced to locate the bundle of his. A fixed helix electrode (Medtronic SelectSecure^TM MRI SureScan^TM3830 ) was than implanted showing selective His-Pacing (Figure 2). Atrial and right ventricular backup electrodes were subsequently implanted (Figure 3).

At three months after surgery, the His-bundle threshold was 1,5V with an impedance of 513Ohm. The patient presented with NYHA class I and normal ejection fraction (EF 60%).

Discussion

In the presence of an isolated persistent left superior vena cava (PLSVC) implantation of pacemaker electrodes can be challenging. The present case demonstrates that, with the use of a steerable sheath, it is possible to achieve direct His-bundle pacing in this setting.

Figure 1: Sinus rhythm, HF 49/min, first degree AV-Block (PQ 300 ms)

Figure 2: Selective His-Bundle Pacing

Figure 3: Chest radiograph demonstrating the final His-bundle and pacemaker lead positions (RA: Right atrial electrode, His: His-bundle electrode; RV: right ventricular electrode)