Medical Device Daily

Demonstrating its intention to move into an expanded area of the ventricular assist device (VAD) space,WorldHeart (Oakland, California) recently reported the first human implant, earlier this month, of its rotary VAD at St. Luke's Hospital (Thessaloniki, Greece). The procedure marked the start of the company's first-in-man feasibility study of this advanced-generation device.

A surgical team, whose members had completed training at WorldHeart's Salt Lake City facility in February, implanted the device into a 67-year-old man with advanced congestive heart failure, in conjunction with an operation that included heart valve repair as well as a coronary artery bypass graft.

The rotary VAD was added to the WorldHeart portfolio with its August 2005 acquisition of MedQuest Products (Salt Lake City), developer of the HeartQuestVAD (Medical Device Daily, Aug. 3, 2005).

WorldHeart is the developer of the Novacor LVAS and HeartSaver VAD systems which are pulsatile systems – meaning having bearings that produce a sort of beating “pulse.“ Thus, at the time it purchased MedQuest, WorldHeart president and CEO Jal Jassawalla noted the company's expansion into the non-pulsatile arena with the complementary rotary device. “Our industry needs both pulsatile and rotary pumps to treat the full spectrum of clinical needs of end- and late-stage heart failure patients,“ he said at the time.

WorldHeart describes this device as the only bearingless, fully magnetically levitated implantable centrifugal rotary pump in clinical trials. It is a continuous flow pump that uses magnetic levitation to fully suspend a spinning rotor, its only moving part, inside a compact housing. The pump's proprietary levitation technology employs a combination of passive magnetic suspension and single-axis active control.

In this description, the term “bearingless“ is key, specifically in terms of the device's compatibility with blood and the ability to avoid thrombosis and clotting that may be caused by the contact between blood and mechanical bearings.

“This is absolutely crucial,“ Jassawalla told Medical Device Daily. “We're not just talking about standard biocompatibility. The system has been designed to be the best ever for hemocompatibility, for its flow characteristics, with magnetic suspension – a bearing-free unobstructed blood pathway across the widest range of operation possible.“

The unobstructed flow of blood around a magnetically levitated rotor, “translates, we hope,“ Jassawalla said, “to extreme gentleness to red cells and white cells.“ This, in turn, will result in the ability to use “anti-platelet therapy only and minimal anticoagulation therapy“ following implantation, he said.

The first-in-man trial follows significant animal and bench testing and will enroll five patients, with a focus on demonstrating safety. “The idea,“ Jassawalla said, “is to get critical information on how [the device] interacts with physiology control systems, blood compatibility and the blood flow pathway.“

The feasibility study then will be followed by other European trials, sometime by the end of 2006 or early 2007, to support application for CE marking.

The first-in-man trial is focused on use of the rotary device as bridge-to-transplant, with the patient being very high risk, but the study researchers also are hoping for some degree of heart function recovery in this patient.

Dr. James Long, cardiac surgeon and director of the Utah Artificial Heart Program – and one of the physicians assisting in the first implantation – called the focus on recovery “extremely important“ in terms of the possible opportunity to take very sick Class III/IV patients “back to Class II – a functional state. That would be a significant plus for the field, an advancement of an area we know will be extremely promising,“ he told Medical Device Daily.

Future trials in the U.S., Jassawalla indicated, will likely focus on using the rotary VAD system to support patients “for multiple years.“

While he noted WorldHeart's initial focus on pulsatile systems, he said that the company is stretching to become “the lead supplier of pulsatile systems and the leading supplier of rotary systems.“ And as a corollary to this, he noted the strong clinical focus of matching the right device to the right patient.

“What we brought to the party,“ he added, “is a relatively mature quality system, an infrastructure, a small team in Europe and a robust qualification unit. It was very much taking what was already developed [by HeartQuest] to the clinical stage and adding our experience and final testing.“

He acknowledged that development of the rotary VAD for longer term support “will take a few years“ but that ultimately the device could address a worldwide population of from 50,000 to 100,000 and be a financial opportunity of from $3.5 billion to $7 billion.

A clear positive, he noted, is current reimbursement in place for bridge-to-transplant use of the device and support of clinical trials.

An additional need, he said, is “to get the cardiologist to support the field. It's happening at a slower rate . . . but more and more of our surgical colleagues are cooperating.“

Antonis Pitsis, MD, cardiac surgeon, director of the Thessaloniki Heart Institute at St. Luke's Hospital, and principal clinical investigator of the feasibility trial, said, “Our surgical and clinical team is extremely pleased to perform the first implant of this unique new device. The WorldHeart rotary VAD has, thus far, met our high expectations, and it has been particularly rewarding to see the patient doing well. The patient is enjoying interacting with his family.“

Dr. Petros Sfirakis, deputy director of cardiac surgery at the Onassis Cardiac Surgery Center (Athens, Greece), assisted with the operation. The Onassis Cardiac Surgery Center has experience with WorldHeart's Novacor pulsatile VAD, which is CE-marked, and is collaborating with St. Luke's in the initial clinical trial of the WorldHeart rotary VAD.

World Heart has additional facilities in Salt Lake City and in Heesch, the Netherlands. WorldHeart's registered office is Ottawa, Ontario.