Summary
Technologies associated with cardiac resynchronization therapy (CRT) devices and lead systems have progressed. However, dislocation after coronary sinus (CS) lead placement continues to be a problem. Furthermore, CS lead positioning at the site of the ventricular latest activation (detected by echocardiography) is often problematic due to large vessel size leading to the lead placement (wedge site) near the apical site. The newly available active fixation CS lead (StarFix 4195) enabled us to anchor the CS lead at the target site regardless of vessel size and availability of a wedge site. We report on seven patients who had previously failed conventional CS lead positioning due to large vessel size and a low phrenic nerve stimulation threshold at the optimal site and lack of stabilization followed by dislocation at the target vein. We attempted to replace the original lead with the StarFix 4195. All patients successfully underwent StarFix 4195 lead replacement at the target site and responded to CRT in the long-term follow-up period.
Keywords: Active fixation coronary sinus lead, Cardiac resynchronization therapy, Pacemaker lead dislocation
Introduction
The newly available active fixation coronary sinus (CS) lead (StarFix 4195™, Medtronic Inc., Minneapolis, MN, USA) is a unipolar, steroid eluting, over the wire left ventricular (LV) pacing lead characterized by three deployable lobes which can be deployed by advancing the outer pushing tube of the proximal catheter. The StarFix 4195 lead has enabled us to anchor the CS lead at the target site regardless of vessel size and availability of a wedge site, and decreased the rate of lead dislocation which might be followed by LV capture threshold rise and/or appearance of phrenic nerve stimulation. We report the first experience of cardiac resynchronization therapy (CRT) using the StarFix 4195 CS lead system in Japan.
Case report
From November, 2007 through March, 2009, seven patients (six males and one female; median age 69 years; range 36–80 years) experienced failure of CS lead placement and therefore underwent active fixation within the target coronary vein using the StarFix 4195 lead. All patients had severely decreased LV ejection fraction (<35%) and were in New York Heart Association functional class III or IV despite optimal drug therapy. Etiologies of heart failure in the seven patients are shown in Table 1. CRT pacemakers or CRT defibrillators were implanted with standard techniques using an endovascular approach via a left axillary vein. Target coronary vein branch for the optimal CS lead positioning (according to findings of echocardiography) was determined after CS venogram. The conventional CS lead systems (Attain 4193 and 4194) were used for LV pacing in all patients. We used the StarFix 4195 only in patients who had failed conventional CS lead positioning due to lack of “wedge position” because of large vessel size, a low phrenic nerve stimulation threshold at the optimal site, and dislocation at the target vein even after successfully positioned at the “wedge position”. Because the StarFix 4195 lead had not been approved for clinical use in Japan (before April 2009), the medical ethics committee at Ehime University Hospital approved the individual import and usage of the lead. All patients gave written informed consent. All patients were followed up and echocardiographic data were obtained every 3 months. CRT responder status was defined by a decrease in LV end-systolic volume of ≥15% using the modified biplane Simpson's method at follow-up echocardiography.
Table 1.
Details of seven patients who underwent StarFix 4195 lead replacement.
| Patient | Age | Sex | NYHA class | Diagnosis | Cause of StarFix use | Effect of CRT |
|---|---|---|---|---|---|---|
| 1 | 69 | M | III | CHF after DDD pacing | Dislocation of Attain 4194 | Responder |
| 2 | 80 | M | III–IV | DCM | Dislocation of Attain 4193 | Responder |
| 3 | 36 | M | III | Corrected TGA | PN stimulation at the optimal site | Responder |
| 4 | 78 | M | III–IV | CHF after DDD pacing | PN stimulation at the optimal site | Responder |
| 5 | 72 | M | III | OMI | PN stimulation at the optimal site | Responder |
| 6 | 71 | M | III | DCM | Dislocation of Attain 4194 | Responder |
| 7 | 77 | F | III–IV | Cardiac sarcoidosis | Dislocation of Attain 4194 | Responder |
CHF, congestive heart failure; CRT, cardiac resynchronization therapy; DCM, dilated cardiomyopathy; NYHA, New York Heart Association; OMI, old myocardial infarction; PN, phrenic nerve; TGA, transposition of the great arteries.
Clinical data for the seven patients are shown in Table 1. The StarFix 4195 was used because of a low phrenic nerve stimulation threshold at the “wedge position” in three patients, and a lack of stabilization followed by dislocation when the tip of the pacing lead was inserted at the “wedge position” in four patients. All patients successfully underwent StarFix 4195 lead replacement at the target vein (fully deployed within lateral or posterolateral branch of the coronary vein) without complications. The parameters for sensing (R wave of 11 ± 7 mV) and pacing (threshold at 0.4 ms pulse width of 1.4 ± 1.3 V) were all acceptable. A representative case is shown in Fig. 1. After a follow-up period of 12 ± 6 months, none of the leads have dislodged. Results have been completely satisfactory, with adequate sensing and pacing function. As compared with baseline, LV ejection fraction and LV end-systolic volume improved significantly after long-term follow-up (Fig. 2). All patients were considered responders to CRT by echocardiography. Thus, the StarFix 4195 is a useful device for reducing the frequency of CS lead failure during and after CRT device implantation and thereby maximizing the efficacy of CRT.
Figure 1.
Representative case. (A) Coronary venography (right anterior oblique view) of patient 1 (upgrade from DDD) showing the target lateral vein, which was relatively straight and lacked vessel branches of appropriate size for wedging at the mid-portion of the vessel. Of note, the posterior vein was not suitable for coronary sinus (CS) lead placement because that resulted in an insufficient distance between the CS and the right ventricular lead tips, possibly leading to unfavorable effects of cardiac resynchronization therapy. (B) Final CS lead position (Medtronic Attain 4194) in the lateral vein with guidewire protruding at the time of the initial operation. Note the tip of CS lead was wedged at a more apical portion. (C) The Attain 4194 lead dislocated soon after the guiding catheter was removed. (D) During the second operation, the StarFix 4195 CS lead was used for active fixation within the mid-portion of the lateral coronary vein. (E) The CS lead maintained a stable position after the guiding catheter was removed. The space between the indicator rings is reduced indicating that all the three lobes were deployed. Pacing and sensing performance were all acceptable.
Figure 2.
Changes in left ventricular end-systolic volume (LVESV) and left ventricular ejection fraction (LVEF). Both parameters significantly improved during long-term follow-up after cardiac resynchronization therapy. The changes in echocardiographic variables from baseline to follow-up were compared using Student's paired t-test. A level of statistical significance was set as p < 0.05.
Discussion
CRT is widely recognized as a treatment for chronic heart failure in patients with severely impaired LV systolic function combined with dyssynchrony [1], [2]. Although the most delayed electromechanical activation site should be paced to maximize the effect of CRT [3], [4], [5], [6], standard transvenous CS lead placement at the site of the ventricular latest activation (detected by echocardiography) is often challenging because of anatomic conditions such as a lack of adequate branches of coronary veins, low phrenic nerve stimulation thresholds, and high LV capture thresholds. Even when such problems are not encountered, CS lead stabilization at the optimal site can become impossible if a “wedge position” is not available due to large vessel size. Furthermore, dislocation after successful CS lead placement at the target vein remains an issue.
CS lead dislocation occurs in 8–11% of patients who undergo CRT device implantation without active fixation of the CS lead [7] and it is one of the critical problems affecting patients who undergo CRT device implantation. Dislocation is associated with LV capture loss and phrenic nerve stimulation, which might result in repositioning of the CS lead after the initial procedure. In order to avoid CS lead dislocation, the pacing lead should be inserted at the “wedge position”. However, that position is often located near the apical site, resulting in a decreased distance from the right ventricular pacing lead positioned at the apex. This may lead to a decrease in the CRT responder rate [8]. Even when the CS lead is positioned at the “wedge position”, dislocation of the lead can still occur. Previous reports have suggested the usefulness of other CS lead stabilization techniques such as stenting [9] or active fixation using a screw-in lead [10]. However, CS lead placement using the StarFix 4195 lead is safer than the other methods in terms of a reduced risk of perforation and insulation defects of the pacing lead. A major limitation of the StarFix 4195 lead placement is extractability after long-term implantation, particularly in cases of lead infection. Because there are no published data regarding any type of CS lead extraction, additional studies in a larger patient population are needed. Nonetheless, taking the poor prognosis of drug refractory heart failure into consideration, we think the CS lead positioning at the optimal site is a first priority.
Conclusion
Despite limited data, our results indicate that the newly available StarFix 4195 CS lead reduces the frequency of lead dislocation and maximizes the efficacy of CRT.
References
- 1.Abraham W.T., Fisher W.G., Smith A.L., Delurgio D.B., Leon A.R., Loh E., Kocovic D.Z., Packer M., Clavell A.L., Hayes D.L., Ellestad M., Trupp R.J., Underwood J., Pickering F., Truex C. Cardiac resynchronization in chronic heart failure. N Engl J Med. 2002;346:1845–1853. doi: 10.1056/NEJMoa013168. [DOI] [PubMed] [Google Scholar]
- 2.Takamatsu H., Tada H., Okaniwa H., Toide H., Maruyama H., Higuchi R., Kaseno K., Naito S., Kurabayashi M., Oshima S., Taniguchi K. Right bundle branch block and impaired left ventricular function as evidence of a left ventricular conduction delay. Circ J. 2008;72:120–126. doi: 10.1253/circj.72.120. [DOI] [PubMed] [Google Scholar]
- 3.Butter C., Auricchio A., Stellbrink C., Fleck E., Ding J., Yu Y., Huvelle E., Spinelli J., Pacing Therapy for Chronic Heart Failure II Study Group Effect of resynchronization therapy stimulation site on the systolic function of heart failure patients. Circulation. 2001;104:3026–3029. doi: 10.1161/hc5001.102229. [DOI] [PubMed] [Google Scholar]
- 4.Becker M., Kramann R., Franke A., Breithardt O.A., Heussen N., Knackstedt C., Stellbrink C., Schauerte P., Kelm M., Hoffmann R. Impact of left ventricular lead position in cardiac resynchronization therapy on left ventricular remodeling. A circumferential strain analysis based on 2D echocardiography. Eur Heart J. 2007;28:1211–1220. doi: 10.1093/eurheartj/ehm034. [DOI] [PubMed] [Google Scholar]
- 5.Ypenburg C., van Bommel R.J., Delgado V., Mollema S.A., Bleeker G.B., Boersma E., Schalij M.J., Bax J.J. Optimal left ventricular lead position predicts reverse remodeling and survival after cardiac resynchronization therapy. J Am Coll Cardiol. 2008;52:1402–1409. doi: 10.1016/j.jacc.2008.06.046. [DOI] [PubMed] [Google Scholar]
- 6.Kiuchi K., Yoshida A., Fukuzawa K., Takano T., Kanda G., Takami K., Hirata K. Identification of the right ventricular pacing site for cardiac resynchronization therapy (CRT) guided by electroanatomical mapping (CARTO) Circ J. 2007;71:1599–1605. doi: 10.1253/circj.71.1599. [DOI] [PubMed] [Google Scholar]
- 7.Nägele H., Azizi M., Hashagen S., Castel M.A., Behrens S. First experience with a new active fixation coronary sinus lead. Europace. 2007;9:437–441. doi: 10.1093/europace/eum061. [DOI] [PubMed] [Google Scholar]
- 8.Heist E.K., Fan D., Mela T., Arzola-Castaner D., Reddy V.Y., Mansour M., Picard M.H., Ruskin J.N., Singh J.P. Radiographic left ventricular-right ventricular interlead distance predicts the acute hemodynamic response to cardiac resynchronization therapy. Am J Cardiol. 2005;96:685–690. doi: 10.1016/j.amjcard.2005.04.045. [DOI] [PubMed] [Google Scholar]
- 9.Cesario D.A., Shenoda M., Brar R., Shivkumar K. Left ventricular lead stabilization utilizing a coronary stent. Pacing Clin Electrophysiol. 2006;29:427–428. doi: 10.1111/j.1540-8159.2006.00365.x. [DOI] [PubMed] [Google Scholar]
- 10.Hansky B., Vogt J., Gueldner H., Schulte-Eistrup S., Lamp B., Heintze J., Horstkotte D., Koerfer R. Implantation of active fixation leads in coronary veins for left ventricular stimulation: report of five cases. Pacing Clin Electrophysiol. 2007;30:44–49. doi: 10.1111/j.1540-8159.2007.00578.x. [DOI] [PubMed] [Google Scholar]