Read journal articles, abstracts and other clinical evidence related to CRT management and the Quartet™ Quadripolar LV Lead:

• Reduced mortality associated with quadripolar compared to bipolar left ventricular leads in cardiac resynchronization therapy.

  Turakhia, M., Cao, M., Fischer, A., Nabutovsky, Y., Sloman, L. S., Dalal, Nirav., Gold, M. R. (2018). J Am Coll Cardiol EP. 2(4). 426-33.

  Conclusions: In this observational study of CRT-D devices, use of a quadripolar, compared to a bipolar LV lead, was associated with a reduction in LV lead deactivation, replacement, and mortality.

• Less with More: Hospitalization cost and Event Rates with Quadripolar versus Bipolar CRT-D.

  Corbisiero, R., Kazemian, P., Bharmi, R., Shar, R., Muller, D. (2016). PACE 39(10). 1038-1045.

  Conclusion: This U.S. economic comparative study demonstrated that QUAD exhibited lower postimplant inpatient HFH rates and reduced healthcare utilization compared to BIP systems.

• Hospitalization rates and associated cost analysis of cardiac resynchronization therapy with an implantable defibrillator and quadripolar vs. bipolar left ventricular leads: a comparative effectiveness study.

  Forleo, G. B., Di Biase, L., Bharmi, R., Dalal, N., Panattoni, G., Pollastrelli, A., … Romeo, G. (2015). Europace, 17(1), 101-107.

  Conclusions: In this comparative effectiveness assessment of well-matched groups of CRT-D patients with quadripolar and bipolar LV leads, QUAD patients experienced a lower rate of hospitalizations for HF and LV lead surgical revision, and a lower cost burden. This has important implications for LV pacing lead choice.

• Post-operative performance of the Quartet™ Left Ventriocular Heart Lead.

  Tomassoni, G. Baker, J., Corbisiero, R., Love, C., Martin, D., Niazi, I., … Zhang, Z. (2013). J Cardiovasc Electrophysiol 24(4). 449-456.

  Conclusions: The Quartet LV lead electrical performance was stable and was associated with a high implant success and low dislodgement rate during 3‐month follow‐up. In all patients with PNS, the 10 pacing vectors combined with reduced output programming enabled the elimination of PNS noninvasively.

• Decreased rate of left ventricular lead deactivation and replacement associated with use of quadripolar LV leads.

  Turakhia, M. P., Gold, M. R., Fischer, A., Sloman, L. S., Kumar, C., Dalal, N., … Cao, M., (2013). Europace, 15(Suppl. 2), S47.

  Conclusions: Compared to traditional bipolar LV leads, use of the Quartet LV lead was associated with a significantly lower rate of deactivation or replacement at 3 months post-implant. At both initial programming and during follow-up, nearly half of all Quartet LV lead patients were programmed to vectors unique to the Quartet LV lead.

• First prospective, multi-centre clinical experience with a novel left ventricular quadripolar lead.

  Sperzel, J., Dänschel, W., Gutleben, K. J., Kranig, W., Mortensen, P., Connelly, D., … Rinaldi, C. A. (2012). Europace, 14(3), 365-372.

  Conclusion: The new quadripolar electrode LV lead provides more programming options to address common problems faced when managing CRT patients. Electrical measurements from new vectors are comparable with conventional configurations. Furthermore, 11% of patients in the study suffered PNS on all conventional bipolar vectors.

• Clinical and procedural outcome of patients implanted with a quadripolar left ventricular lead: Early results of a prospective multicenter study.

  Forleo, G. B., Mantica, M., Di Biase, L., Panattoni, G., Della Rocca, D. G., Papavasileiou, L. P., … Romeo, F. (2012). Heart Rhythm, 9(11), 1822-1828.

  Conclusion: Over the longer term, CRT with the quadripolar LV lead is associated with excellent pacing thresholds, low rates of dislocations, and PNS.

• Elimination of phrenic nerve stimulation occurring during CRT: Follow-up in patients implanted with a novel quadripolar pacing lead.

  Mehta, P. A., Shetty, A. K., Squirrel, M., Bostock, J., & Rinaldi, C. A. (2012). Journal of Interventional Cardiac Electrophysiology, 33(1), 43-49.

  Conclusion: The quadripolar Quartet LV lead is associated with a high implant success rate, stable pacing parameters and a low displacement rate during the first 6 months after implant. The ten LV pacing vectors available with this lead allowed PNS and capture threshold problems to be overcome at implant, and importantly at follow-up, thus obviating the need for lead reposition.

• Left ventricular pacing with a new quadripolar transvenous lead for CRT: Early results of a prospective comparison with conventional implant outcomes.

  Forleo, G. B., Della Rocca, D. G., Papavasileiou, L. P., Molfetta, A. D., Santini, L., & Romeo, F. (2011). Heart Rhythm, 8(1), 31-37.

  Conclusion: This prospective, controlled study provides strong evidence that CRT with the quadripolar LV lead results in low rates of dislocations and phrenic nerve stimulation.

• A new quadripolar lead for left ventricular pacing: Short term reliability and future opportunities.

  Viani, S. M., Segreti, L., Di Cori, A., Zucchelli, G., Paperinin, L., Soldati, E., … Bongiorni, M. G. (2011). Europace, 13(Suppl. 3).

  Conclusions: Our preliminary data show that this quadripolar LV lead is reliable and can provide many advantages over conventional bipolar LV leads (more opportunities to ensure LV capture and to avoid PNS without adjusting lead position, ability to ensure lead stability without sacrificing middle or basal pacing sites). Further studies are required to identify the real clinical benefits of this new tool.

• LV-pacing: Vector optimization using a novel quadripolar electrode acutely improves cardiac output in cardiac resynchronization therapy patients.

  Gutleben, K. J., Kranig, W., Barr, C., Morgenstern, M. M., Simon, M., & Dalal, Y. H. (2011). Europace, 13(3), P403.

  Conclusions: VSQ pacing using the quadripolar electrode improved acute hemodynamics in >50% of patients at PD and >40% of patients at 1MFU. The use of VSQ might reduce non responder rates in CRT.

• A new insulation material for cardiac leads with potential for improved performance.

  Jenney, C., Tan, J., Karicherla, A., Burke, J., & Helland, J. (2005). Heart Rhythm, 2(5), S318-319.

  Conclusions: The new SPC™ insulation exhibits significantly improved performance over both silicone rubber and polyurethane. Its flexibility and softness can result in a substantial reduction of lead tip stiffness compared to polyurethane 55D. Invivo testing has shown that biostability of the SPC™ is at least as good as, or better than current polyurethane 55D. SPC™ is expected to be a reliable insulation for future use in cardiac leads. Further studies with SPC are in progress.