A persistent left superior vena cava (PLSVC) is a rare abnormality that presents a challenge to the implanter. Its incidence varies from 0.3–0.5% of the population.1,2 It has always been recommended that the right superior vena cava (RSVC) be used for implantation of arrhythmia control devices in patients with PLSVC.9 In many such cases (about 10–17%), the right superior vena cava is also absent.5 A few reports have described different approaches in different clinical situations.6–8 To our knowledge, this is the first case report of implantation of dual-chamber pace maker via PLSVC utilizing a steerable stylet (the Locater™; St. Jude Medical, Inc., Minnetonka, Minnesota) with chronic follow-up showing stable threshold. Case Report. An 86-year-old male with past medical history of hypertension and coronary artery disease presented with multiple syncopal episodes; the Holter monitor revealed episodes of sinus pauses. In the Electrophysiology Laboratory, during the introduction of the guiding wire via left subclavian approach, it was noted that the guidewire was going to the left side of the spine in the anterior-posterior fluoroscopic projection. A venogram was obtained, which confirmed the finding of persistent left superior vena cava. The ventricular lead was advanced through the LSVC and the coronary sinus into the right atrium; multiple maneuvers and adjustments to the stylet were not helpful. A steerable stylet (the Locater™, model 4036; Pacesetter, a trademark of St. Jude Medical, Inc.) was used. By adjusting the tip of the stylet as needed in the right atrium, we were able to direct the tip of the lead toward the tricuspid valve and implant it at the right ventricle. A passive fixation lead was used (model 5034; Medtronic AVE, Santa Rosa, California) (Figure 1). The right atrium lead was implanted with no difficulties utilizing the same type of stylet; a passive fixation lead (model 4568) was used (Figure 2). Pacing and sensing threshold and the CXR at three months were stable (Figure 3). Discussion. A persistent left superior vena cava is a rare abnormality. Its incidence varies between 0.3–0.5% of the population;1,2 it represents the most common abnormality of venous return to the heart. PLSVC results from the embryological persistence of the left common cardinal vein and its caudal junction with the left duct of Cuvier.3,4 The PLSVC reaches the right atrium via the coronary sinus and is accompanied by a normal right superior vena cava; in about 10–17% of cases, the right superior vena cava is absent.5 Implantation of the ventricular lead through the left superior vena cava has always been a challenge due to the angle the lead should take to enter into the right ventricle, and due to the possibility of dislodgement. Many reports have described a successful implantation due to improved techniques or due to multiple intra-cardiac maneuvers6,7 or using a double superior vena cava;8 most of the case reports used an active fixation lead. To our knowledge, this is the first case reporting the use of a steerable stylet (the Locater) for implanting a passive fixation lead in the right ventricle. The Locator is a multi-functional mechanical tool that allows the physician to define and vary the curvature of the distal portion of the lead without removing the stylet from the lead.
1. Spearman P, Leier CV. Persistent left superior vena cava: Unusual wave contour of left jugular vein as the presenting feature. Am Heart J 1990;120:999‚Äì1002. 2. Campell M, Deuchar DC. Left-side superior vena cava. Br Heart J 1954;16:423‚Äì439. 3. Dirix LY, Kersschot IE, Fierens H, et al. Implantation of dual chamber pacemaker in a patient with persistent left superior vena cava. PACE 1988;11:343‚Äì345. 4. Horrow JC, Lingaraju N. Unexpected persistent left superior vena cava: Diagnostic clues during monitoring. J Cardiothorac Anesth 1989;3:611‚Äì615. 5. Ronnevik PK, Abrahamsen AM, Tollefsen I. Transvenous pacemaker via a unilateral left superior vena cava. PACE 1982;5:808‚Äì813. 6. Hsiang Chiang Hsiao, et al. Right ventricular lead implantation via a persistent left superior vena cava. Angiology 1997;10:919‚Äì923. 7. Okreglicki AM, et al. VDD pacing using the persistent left superior vena cava. PACE 1998;21:1189‚Äì1191. 8. Garg A, et al. Dual chamber pacemaker implantation via a double superior vena cava. PACE 2000;23:142‚Äì143. 9. Furman S, et al. A Practice of Cardiac Pacing, Third Edition. pp. 300.