Chennai doctors implant advanced leadless pacemakers in 75 and 92-year-old patients

Doctors at the Madras Medical Mission (MMM) hospital in Chennai recently implanted a true dual-chamber leadless pacemaker in two patients aged 75 and 92. A first-of-its-kind in elderly patients, implanting the small, self-contained device directly into the heart is considered to be the next big revolution in cardiac surgery.

While pacemaker implant is not new in cardiac treatments, these leadless pacemakers involve less physical trouble and a minimal surgical procedure compared to the conventional pacemakers. “A leadless pacemaker was safer and more convenient not only to the patient but also for physicians owing to the ease of implantation,” says Dr Ajit Mullasari.

In October, a 75-year-old patient came to the hospital complaining of tiredness and dizziness, with his daily activities becoming very minimal. He came with a complete heart block. After all the initial tests, the doctors decided that he needed a pacemaker to bounce back to normal life. But, given his age, the risk involved and the high rate of infection with conventional pacemakers, the doctors opted for the leadless pacemaker.

It was implanted directly inside the heart, unlike conventional pacemakers, which involve a battery under the collarbone and two wires connecting it to the heart. The leadless pacemakers do not have the pulse generator which is placed under the skin near the collarbone. It is rather a small device involving a minimal surgical procedure.

With the success of the first implant, the doctors were soon ready to go for the second. This time involving a 92-year-old patient. This patient was operated within a couple of weeks, and both have walked back home like normal individuals, without any risk of infection or post-surgery care. “By avoiding wires and surgical pockets like in the conventional pacemakers, we significantly reduce infections, lead dislodgement and other complications. These leadless pacemakers ensure that the patient is comfortable and it accelerates recovery,” says Dr Ajit. 

What is a leadless dual-chamber pacemaker?

A heart patient may need a pacemaker if his or her heartbeat is very slow and the heart cannot pump blood to the body parts. A pacemaker keeps the heart beating regularly and pumps blood efficiently. Modern pacemakers, called the leadless pacemakers, do not need wires. It is like a small, capsule-like metal box containing a high-energy battery. A human heart has nodes and fibres that conduct electrical signals called impulses through the heart’s chambers. The electrical impulses regulate and coordinate the pumping action and contraction of the heart muscles. Each contraction of the ventricles is felt as a heartbeat. When there are problems with the heart’s electrical signals, a pacemaker may be required to regulate the electrical activity. If the heart beats slowly, the pacemaker sends signals, restoring the heartbeat to a regular rate.

This new system, called as the leadless dual-chamber pacemaker, involves two small self-contained devices implanted directly into the heart - the right atrium and the right ventricle. The conventional procedure used to be messy, and the two wires from the generator or the box-type battery may turn infectious, or will be difficult to remove. These wires will have to be replaced. Now, with the leadless pacemakers, the microbes are placed into the heart itself. It is a small cell-like battery which is implanted into the surface of the heart, and so it doesn’t involve any charging battery kept in the upper chamber, i.e, near the collarbone. “Right now, it is a bit big. But over a period of time, this will become smaller,” says Dr Ajit. 

A regular pacemaker involves an open surgery, while the leadless pacemakers can be implanted via a catheter inserted through a vein. These pacemakers are leadless, kept directly in the heart’s chamber without cutting through the chest wall, and have years of battery life. And, there are no chest scars. The procedure takes less than an hour, and the patients can resume their normal activities within a day. 

On the other side, the patients, says Dr Ulhas Pandurangi, will have to be carefully chosen for leadless pacemakers. It is because these devices are not suited for individuals requiring dual ventricular or arterial pacing, those undergoing cardiac resynchronisation therapy or those with difficult vascular access. “This might change in the future as the makers are working on devices that can be placed in the middle of the heart to take control and perform all the activities of a traditional pacemaker,” says Dr Ulhas.  

“These are roughly one-tenth of the size of the conventional pacemakers used all these days,” says Dr Ajit. While these leadless pacemakers are a bit expensive compared to the traditional ones, Dr Ajit is of the opinion that the cost may eventually reduce. However, if the battery lasts longer and the replacements are delayed and easier, it will apparently benefit the patients.