Permanent pacemaker configuration.   The generator is under the skin. A wire is passed into a vein beneath the clavicle and into the right side of the heart (the tip is positioned in the right ventricle). In this example there is a second wire in the right atrium.

I saved this used 1970’s single lead unit made by Cordis in Miami.  The surgeon would place it into a “pocket” under the skin and attach it to an electrode in the heart.   Paul Goldfinger photo. ©

The opposite side of the unit shown.  Cardiologists would go into the OR with the surgeon when a pacemaker was placed. Now, surgeons are usually no longer needed for this procedure. ©  Paul Goldfinger photo

A tiny modern version of a permanent pacemaker.

Current model.

By Paul Goldfinger, MD, FACC,  Dean at the Blogfinger  Off-shore School of Medicine .   Re-posted from Feb. 2016 on Blogfinger.net

My career spanned the remarkable history of permanent cardiac pacemakers. In the early 1970’s, those devices were as a big as a can of tuna fish. They had limited functions and a variety of technical problems. Today they are miniature electronic marvels.

The story began around 1930 when an Australian researcher found that the heart could be stimulated with a localized electrical shock delivered from a wire.

1949: The Medtronic Company, pioneers in pacemakers, was begun in a garage in Buffalo by an engineer and a physician.

1952: At the Boston Beth Israel Hospital, a patient was admitted with fainting spells due to drastic slowing of the heart. These are called Stokes-Adams attacks. This was the first case to be treated with a temporary pacemaker. A wire was attached to the external wall of his heart, while the pacemaker generator was outside his body.

1957: The first battery powered unit was developed, and, in 1958, the first permanent pacemaker was implanted in a dog, consisting of a generator under the skin and a wire attached to the outside wall of the heart.

1960: The first permanent pacemaker was implanted in a human. In 1961, the first in New Jersey was performed by heart surgeon Victor Parsonnet at Newark Beth Israel. Dr. Parsonnet is one of a core group of doctors world-wide to get credit for pioneering work in permanent pacemakers.

1973- 1980: The era when my own career began, the technology of permanent pacemakers evolved strikingly, with smaller and more complicated  “generators,” longer lasting batteries, and better electrode (wire) systems.  Medical electronics had been evolving thanks to the invention of the microprocessor.

When a patient only needed a temporary pacemaker, a cardiologist such as myself would pass a wire into the right ventricle through a vein in the arm or neck and attach it to an external pacemaker which hung from an IV pole at the bedside.  Eileen sometimes kids me by saying, “If you can put a wire into somebody’s heart, how come you can’t…….(fill in the blank)”

The permanent units could just only control slow heart rates at first, but later, more functions were developed and could be programmed (changing the settings) from without.

At first, pacemakers had to be routinely changed every two years because of battery life, but later the batteries were improved.

In the early 1970’s research with a nuclear powered pacemaker was performed by Dr. Parsonnet and his team at Newark’s Beth Israel Hospital . They were trying to increase the battery life.   That technology did not work out.

During this phase, techniques for monitoring the battery life and functions of a permanent pacemaker were developed. Eventually a patient could be followed by the use of a telephone, so hospitals throughout NJ had a setup where they could check their patients by phoning into NBIH for monitoring allowing doctors to predict when a pacemaker had to be changed and how well it was working. In-person visits to a pacemaker clinic were also required to check a variety of other functions .

In late 1970’s, at Dover (NJ) General Hospital and Medical Center, Jean Wiarda, RN ( a cardiac nurse) and myself,  with the cooperation of Medtronic, set up the first free-standing pacemaker clinic in north Jersey. After that, many other hospitals followed suit and broke away from the NBIH connection.  Later patients were able to phone in  their pacemaker signals from home  to the clinics. They also had to come for in-person evaluations intermittently depending on what we wanted to measure or program.

A major development, evolving in the 1970’s, was the transvenous lead for permanent pacemakers which eliminated the need to open the chest and sew an electrode into the heart muscle.   Instead, an electrode could be passed through a vein under the collar bone and into the right ventricular chamber, eliminating the need for heart surgery.

Now that continues to be standard, although the pacemaker generators are much smaller, and the electrodes have been refined, and sometimes more than one wire is used. Even though the generators are now tiny (you can’t even tell that someone has a unit,) they can perform all sorts of miraculous functions and are totally adjustable from without using a device called a programmer.

Surgeons used to install permanent transvenous pacemakers, but now these complex devices are placed by electrophysiologists, cardiologists who specialize in electrical diagnostics and therapeutics including implantable cardio-defibrillators.

The future of electrophysiology is huge, and progress is made every day in this field.

The latest development, currently  being perfected is that of wireless pacemakers, meaning no wires into the heart.  This will revolutionize the field since about 250,000 permanent pacemakers are placed yearly in the US, and about 750,000 around the world.

Around here, Jersey Shore Medical Center and Morristown Medical Center have first rate electrophysiology departments.

Editor’s note  10/30/20:  Thanks to Dr. Eran Zacks, FACC, FHRS   (Fellow  Heart Rhythm Society) of Monmouth Cardiology for updating us on new rhythm monitoring techniques and wireless pacemakers.

THE TIMETONES

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