SA pioneers micro tech in the heart

A tiny leadless pacemaker – the first of its kind in South Africa and a fraction of the size of a AAA battery – has been successfully implanted in the chamber of a patient’s heart in a sophisticated, minimally invasive procedure at Netcare Unitas Hospital recently.

Cardiologist Dr Jean Vorster and electrophysiologist Dr Jane Moses performed the country’s first implant of an AVEIR VR Leadless Pacemaker (LP) in late November, marking a milestone in next generation treatment for heart rhythm disorders with the latest in LP microtechnology.

“Although pacemakers have become smaller with longer battery life over the past two to three decades, there has been little advancement in the therapy,” says Dr Vorster, a renowned cardiologist practising at Netcare Unitas Hospital.

“This latest iteration of pacemaker technology not only eliminates the need for leads, which are usually implanted through the veins leading to the heart, but there is also the aesthetic advantage that the patient is no longer left with a bulge in their chest as a constant reminder of their condition, because this LP is so small and the minimally invasive direct implant means there is no need for a surgical scar on the chest at all. The AVEIR VR LP is also unique in the considerable advancement in the algorithms and programming of the device,” he says.

“This pacemaker is small enough to fit comfortably within the lower right ventricle of the heart, and while this single chamber device is good news in itself for the treatment of heart rhythm disorders, the major significance of this technology lies in the possibilities it presents for further breakthroughs in the near future,” adds electrophysiologist Dr Jane Moses.

With longer battery life packed into the tiny device measuring just 38mm and only a third of the volume of a standard AAA battery, this flagship VR LP is designed to attach securely to the wall of the heart. The LP is positioned, and retrieved if necessary, using a long, slender catheter system carefully guided to the heart via the femoral vein in the patient’s groin. 

The system’s capabilities include mapping before placement to enhance precision. The AVEIR VR LP is equipped to measure the electrical impulses of the ventricles, impedance and an initial capture threshold before it is secured in position by attaching the LP’s tip electrode to the heart muscle. Once contact is confirmed, the instrument gently rotates the LP to embed it into the muscular inner wall of the heart’s lower chamber.

Dr Moses points out that, at present, leadless pacemakers such as this remain cutting-edge technology and are usually only considered for individuals for whom conventional pacemakers are unsuitable.

“Leadless pacemakers may be recommended where there is insufficient access to implant leads, or there is an infection present that could become further complicated. As the first in the country and only the second such device implanted on the continent, we are encouraged that this technology is paving the way for further developments,” she says.

“In the not-too-distant future, we can foresee the benefits of this microtechnology for implanting one LP in the ventricle or lower chamber of the heart, and another in the atrium or upper chamber, to stimulate the heart in such a way that brings us closer to more natural pacing to restore regular, healthy heartbeats for a wider range of conditions to bring hope to more patients.”

Immediate advantages of the newer leadless pacemakers for patients include that they eliminate the risks associated with leads degrading or fracturing, as well as the need for more frequent reintervention. There is also less risk of infection without the need for an open surgical wound with the minimally invasive LP placement.

Dr Vorster concludes: “Eliminating leads is really a game-changer in pacemaker technology. In Europe, some patients can return home on the day of the procedure, reducing the need for hospital recovery. Cardiac microtechnology and the prospect of dual chamber devices are no longer science fiction; they are scientific fact.”