Large-scale study confirms growing body of clinical evidence for St Jude Medical quadripolar system


St Jude Medical has announced results from a large-scale, clinical study concluding that the Quartet left-ventricular quadripolar lead provides more options to effectively manage common pacing complications compared to systems with bipolar leads.

The MORE-CRT data, More options available with a quadripolar LV lead provide in clinic solutions to CRT challenges, was presented during a hot line late-breaking session at the European Society of Cardiology Congress 2014 (ESC 2014). Results showed that complications occurred less frequently and were managed more efficiently in patients who received the Quartet lead than in patients who received bipolar electrode leads.

“The risk of left ventricular lead-related events was more than 40% lower in patients implanted with a Quartet CRT-D system relative to patients implanted with a bipolar CRT-D system,” says Giuseppe Boriani of the Institute of Cardiology, University of Bologna, Italy, and the MORE-CRT steering committee chairman. “The overall freedom from intraoperative and post-operative left ventricular lead-related events was significantly higher in quadripolar CRT group versus bipolar CRT group. These data are very important in deciding how we treat our patients going forward.”

More than 60 centres from 13 countries participated in this first randomised, large-scale clinical study of more than 1,000 patients comparing the St Jude Medical Quartet lead to bipolar left ventricular leads (one-third of bipolar leads were St Jude Medical and two-thirds were non-St Jude Medical). The primary endpoint of the study was freedom from intra- and post-operative left ventricular lead-related events at six months.

The Quartet lead was associated with a statistically significant increase in freedom from combined left ventricular lead-related events – 85.97% in patients implanted with a Quartet lead compared to 76.86% in patients implanted with a bipolar LV lead.

“The design of St Jude Medical’s Quartet quadripolar technology is unique,” says Mark D Carlson, chief medical officer and vice president of global clinical affairs for St Jude Medical. “The MORE-CRT study confirms that our quadripolar system has set the standard for the quadripolar pacing industry and the study is a strong addition to the more than 100 publications showing our technology improves outcomes and quality while reducing costs.”

The quadripolar pacing technology is important because failed implant rates in heart failure patients receiving a cardiac resynchronisation therapy (CRT) system are significantly higher with bipolar left ventricular pacing leads due to anatomy (creating lead stability problems), phrenic nerve stimulation (PNS) or poor electrical measurements.