Coronary Venous Angioplasty and Stenting for Biventricular Pacemaker Left Ventricular Lead Implantation
We sought to examine whether cardiac vein angioplasty and/or stenting would allow for the proper placement of the LV lead in these patients. Few prior reports3–5 have examined this common technique used in the coronary arteries specifically for the coronary venous system for the facilitation of LV BVP lead placement.
Case Report 1. An 83-year-old male with a history of coronary artery disease, status post coronary artery bypass graft surgery and pacemaker for heart block was referred for biventricular implantable cardioverter defibrillator (ICD) implantation because of congestive heart failure, despite optimal medical therapy and an ejection fraction of 30%. An attempt was made to upgrade his permanent pacemaker to a biventricular ICD, but there was a stenosis of the LV vein, thus a regular ICD was implanted. He returned for upgrade of his standard ICD to a biventricular ICD with the adjunctive use of venoplasty to allow passage of the LV lead.
At implantation, angioplasty over a 0.014 inch guidewire with a 3.5 mm x 20 mm balloon inflated to 8 atmospheres (atm), was accomplished with no significant residual stenosis. No anticoagulation was used to prevent bleeding from the implant incision site. Subsequent LV pacing lead (Guidant® Model 4513, Guidant Corp., Indianapolis, Indiana) advancement into a posterolateral LV vein was accomplished with good pacing (1 V at 0.5 msec) and sensing thresholds (R-wave = 7.6 mV) obtained. Postimplantation transthoracic echocardiography ruled out pericardial effusion or other mechanical complication.
Case Report 2. A 75-year-old male presented to our institution in sustained ventricular tachycardia (VT). His VT cycle length was approximately 390 msec. Subsequent cardiac catheterization demonstrated an overall LV ejection fraction of 8%, with 1+ mitral regurgitation. No coronary artery stenoses of significance were noted. Following catheterization, he continued to experience multiple episodes of sustained VT greater than 48 hours post-elevation in cardiac enzymes. These episodes required electrical cardioversion despite intravenous amiodarone loading and in the absence of acute ischemia. An ICD was implanted at that time, and the patient was discharged home on suppressive amiodarone therapy. A few months later, the decision was made to upgrade the patient to a biventricular ICD, as he continued to have symptoms of class III heart failure despite optimal therapy.
implantation, the coronary sinus was injected with contrast to opacify the coronary venous system. The optimal LV vein was stenosed and unable to be crossed (Figure 1). The LV vein stenosis was traversed with a 0.014 inch guidewire and dilated with a 2 x 20 mm Crossail balloon (Guidant®) to 8 atm and a 4 x 20 mm Crossail balloon to 10 atm (Figure 2). No anticoagulation was used to prevent bleeding from the implant incision site. Because of immediate venous recoil in the atrioventricular groove and venous thrombosis, two sequential 4 x 24 mm Medtronic® Driver stents (Medtronic, Inc., Minneapolis, Minnesota) were deployed at 14 atm (Figure 3). Successful placement of the LV lead (Medtronic® Model 4193) was thereafter accomplished in the posterolateral LV vein (Figure 4). V-lead pacing and sensing thresholds (0.9 V at 0.5 msec and R-wave = 6.7 mV, respectively) were noted to be acceptable at implantation and at follow up (0.8 V at 0.5 msec and R-wave = 8 mV, respectively). Postimplantation transthoracic echocardiography ruled out the presence of pericardial effusion or other mechanical complication.
Discussion. While recent advances in lead technology and delivery systems have improved the success rates of LV lead implantation to accomplish LV pacing via a percutaneous approach, anatomic variations often make lead delivery a challenge.6,7 Although coronary vein stenoses are rare, as noted by Hansky et al (4 [1.83%] of 218 patients),5 previous coronary artery bypass graft procedures, scarring after myocardial infarction and previous implantation of a CS lead are all possible etiologies for this entity.5 In one center’s experience,3 10% of patients who underwent BVP implantation had asymptomatic coronary venous stenosis. Symptomatic coronary vein stenosis has not been reported, which is likely due to the presence of abundant collateral circulation.
Stenoses and small-caliber veins, as this report and prior reports show, can be successfully dilated with standard coronary angioplasty catheters and stented, if necessary, for the optimal placement of LV BVP leads. New specifically designed over-the-wire systems that allow dilatation to about > 3 mm allow for placement of these leads and do not result in any intraoperative or postoperative complications. Percutaneous transluminal coronary angioplasty (PTCA) with provisional stenting in this setting is done solely for the purpose of lead advancement. New guides that conform to tortuous coronary sinus anatomy are being developed for the facilitation of pacing lead advancement; however, these guides can still meet resistance in extremely tortuous and/or stenotic areas of the venous system.
Patients who undergo coronary venous stent implantation are not initiated or maintained on antiplatelet therapy. As with any new technique, however, caution is advised with this novel procedure. It should only be performed in centers with extensive experience in the combined techniques of transvenous LV leads and PTCA. Potential complications include venous rupture, resulting in cardiac tamponade and interference with lead threshold. The question of the limits of balloon inflation needs further investigation in order to minimize the risk of venous rupture. Other complications include access site complications due to inadequate length of the delivery catheter, and infection through the open-wound access site in the chest wall. Another complication involves thrombosis of the coronary sinus. This, however, has not been reported to result in significant complications. Further study also needs to be undertaken with respect to the long-term effects of stent implantation in the coronary venous system. A multidisciplinary team consisting of an interventional cardiologist and electrophysiologist is advised, with cardiac surgical backup available.
Conclusion. Coronary vein angioplasty and/or stenting is a novel, safe and effective method to facilitate transvenous LV biventricular pacemaker lead implantation in patients with stenosed or small-caliber cardiac veins that preclude lead implantation through the usual means. We have shown that coronary vein angioplasty and stenting facilitates the placement of the LV lead by providing a mechanical and structural framework for the LV lead.
References
- Cazeau S, Leclercq C, Lavergne T, et al. Effects of multisite biventricular pacing in patients with heart failure and intraventricular conduction delay. N Engl J Med 2001;12:873–880.
- Walker S, Levy S, Rex S, et al. Initial United Kingdom experience with the use of permanent, biventricular pacemakers. Europace 2000;2:233–239.
- Van Gelder BM, Meijer A, Basting P, et al. Successful implantation of a coronary sinus lead after stenting of a coronary vein stenosis. Pacing Clin Electrophysiol 2003;26:1904–1906.
- Sandler DA, Feigenblum DY, Bernstein NE, et al. Cardiac vein angioplasty for biventricular pacing. Pacing Clin Electrophysiol 2002;25:1788–1789.
- Hansky B, Lamp B, Minami K, et al. Coronary vein balloon angioplasty for left ventricular pacemaker lead implantation. J Am Coll Cardiol 2002;40:2144–2149.
- Hansky B, Vogt J, Gueldner H, et al. Left heart pacing — Experience with several types of coronary vein leads. J Interv Card Electrophysiol 2002;6:71–75.
- Gilard M, Mansourati J, Etienne Y, et al. Angiographic anatomy of the coronary sinus and its tributaries. Pacing Clin Electrophysiol 1998;21:2280–2284.