Clinical Trial Tests New LV Lead for Heart Pacing Devices Tiny Screw Anchors Attain Stability Quad Lead to Vein Wall
The world’s first Attain StabilityTM Quad lead was recently implanted in a patient at Ohio State’s Ross Heart Hospital by cardiac electrophysiologist Toshimasa Okabe, MD. Part of an international clinical trial sponsored by medical device manufacturer Medtronic, the Attain Stability Quadripolar MRI SureScan Left Ventricular (LV) lead is being tested for its safety and effectiveness.
The multicenter clinical study is prospective and non-randomized. The global study aims to enroll 471 people with severe congestive heart failure across 56 sites in the U.S., Canada, Europe, Hong Kong and Malaysia.
The LV lead is one of three leads that connect to a quadripolar cardiac resynchronization therapy defibrillator (CRT-D) or a CRT-P (pacemaker). The placement and stability of the lead is critical in delivering electrical impulses to both lower heart chambers to help them beat together in a more synchronized pattern.
A More Versatile and Secure Lead
Dr. Okabe notes some distinct advantages of the Attain Stability Quad lead being tested: “This new lead has an active-fixation mechanism—a small screw that bites into the wall of a vein to hold it in place,” Dr. Okabe says.
Dr. Okabe explains that the stability of the lead is critical for patients who have severe congestive heart failure and are prone to infection. “This could be a real breakthrough. When we prevent the lead from moving or dislodging, we don’t have to re-open the pacemaker pocket and expose the patient to potential infection.”
In addition, the lead has four electrodes (quadripolar) rather than the traditional two electrodes (bipolar) to find the optimal location for pacing the heart. “The lead’s four electrodes give us more options on where to pace from,” says Dr. Okabe.
Through a small incision in the chest, the electrophysiologist introduces three wires and places the third wire (the LV lead) in a small vein around the left ventricular chamber. Dr. Okabe notes, “There’s a lot of anatomical variation in where we can implant the LV lead. Some veins are too small or tortuous, or too big. This Attain Stability Quad lead could be placed in big vessels — even major vessels — and would be unlikely to move. We hope this new design will allow us to implant the lead in a location where conventional leads would have been too unstable.”
Implanting the lead quickly and efficiently is important because “faster procedure time directly correlates with a lower rate of infection,” Dr. Okabe adds.
Addressing Safety Concerns
When implanting CRT devices, electrophysiologists know there’s a 1 percent risk of infection with any cardiac device. The only treatment is to remove the CRT and its leads.Dr. Okabe says developers of the new LV lead carefully calculated a design that could be removed without damaging the walls of a blood vessel.
“Clinicians have expressed concern that placing the lead and screwing it into the wall of the vein would rupture the vessel. That hasn’t been the case in animal or human trials,” Dr. Okabe confirms.
In animal studies, researchers extracted the leads after two years with no problems. No one knows if that task will become more difficult with a lead that’s been in place for 10 to 20 years. “We’re weighing the risk of a potential removal at a later date against improving the quality of life and ability to live longer now.”
Dr. Okabe has successfully implanted close to a dozen LV leads in study participants, with no adverse events. Dr. Okabe is one of eight cardiac electrophysiologists at Ohio State participating in the study.