A treatment that goes only skin deep to help the heart. It delivers a powerful shock with less risk. Now doctors hope the new device will go the distance with their young patients.
Watching 37-year-old Carlos Ahon with his daughters, you’d never guess he’s anything but perfectly healthy.
Jenny Ahon, translating for Carlos: “He was feeling the pain a little bit, but he didn’t pay attention because he always exercises. He didn’t realize something was wrong with him.”
Constantly tired even after sleeping, Carlos finally sought help. His diagnosis … an enlarged heart muscle that worked less efficiently. The condition can lead to sudden cardiac arrest — a rapid electrical rhythm that stops the heart’s ability to pump blood.
Dr. Bradley Knight, Cardiac Electrophysiologist, Northwestern Memorial Hospital: “For every minute that goes by without shocking the heart, survival rate decreases by 10 percent.”
Carlos needed an implanted defibrillator that would zap his heart back into normal rhythm when necessary.
Dr. Knight: “It has pacing electrodes at the end and shocking coils to deliver a shock when the heart goes very fast.”
Jenny Ahon: “He thought it was going to be a radical change for his life, he was very scared.”
With good reason. It’s not an easy install.
Dr. Knight: “The weakest link in the system is the lead that requires being placed inside the heart.”
With a standard defibrillator, doctors snake a lead through a vein under the collarbone down into the heart’s lower chamber — a tricky entrance, but an even trickier exit if the wires or electrodes need to be replaced down the road.
Dr. Knight: “Extracting a transvenous lead is associated with significant morbidity. The risk of dying is about one percent, but we only do it when it’s absolutely necessary. If someone is in their 20s or 30s or 40s and needs an implantable defibrillator, they are going to have it for 30, 40 or 50 years, that lead can fail, and it becomes a very big problem.”
But now Northwestern Memorial cardiac electrophysiologist Dr. Bradley Knight has a solution — a new subcutaneous device that takes some of the risk out of the game.
Dr. Knight: “There is a lead, but it’s placed entirely under the skin. It’s not placed in the heart. This lead is tunneled under the skin and laid adjacent to the chest bone and attached to this defibrillator, which is placed here below the armpit. If anything were to go wrong this could be taken out pretty easily without having to extract the lead from outside the heart.”
Two and a half years after he received the new device as part of a clinical trial, Carlos is thankful he gave it a shot.
Jenny Ahon, Carlos’ wife: “He feels a lot more secure now, especially after receiving a shock six months after he was implanted. Then he saw the necessity for the defibrillator. He can do everything he wants to.”
Dr. Knight: “A shock is your friend and it saves your life.”
There are some trade-offs – the subcutaneous defibrillator is bulkier than standard models, and it can’t deliver pacing for congestive heart failure or arrhythmias. For more information, visit Northwestern’s Bluhm Cardiovascular Institute’s website www.heart.nmh.org.