New implantable device treats heart failure
Baylor College of Medicine doctors are now treating heart failure patients using a novel implantable device that works by making the heart beat stronger. A team lead by Dr. Mihail Chelu, associate professor of medicine – cardiology and director of electrophysiology at Baylor Heart Clinic, implanted the first ‘Optimizer Smart System’ at Baylor St. Luke’s Medical Center and the larger Texas Gulf Coast area .
The management of patients with heart failure is complex and requires the collaborations between electrophysiologists. Chelu was assisted by Dr. Austin Howard, clinical postdoctoral fellow in electrophysiology at Baylor, and the electrophysiology team at Baylor St. Luke’s. He also worked closely with heart failure specialist Dr. Ajith Nair, assistant professor of medicine – cardiology at Baylor.
“Heart failure occurs when the muscles of the heart weaken,” Chelu said. “It can be caused by a number of issues such as a heart attack, narrowed arteries or chronically high blood pressure. The muscles become damaged and cannot pump properly to supply the body with oxygenated blood it needs to function normally. This can be a slow, painful progression that can lead to death. While this new device cannot fix the heart so to speak, it does improve heart function, which decreases shortness of breath and improves the ability to perform physical activity. Overall, it improves the quality of life for those living with heart failure.”
A typical measurement for heart failure, known as the ejection fraction (EF), looks at the overall percentage of blood leaving the heart with each contraction; a normal EF reading is above 55 percent. This device is indicated for patients with EF between 25-45 percent and with marked limitation of physical activity, but who are comfortable at rest. They also experienced fatigue with less than ordinary physical activity (this class of heart failure rating is called New York Heart Association class III).
“The outcomes are that patients can walk further, have longer conversations and not tire as easily, giving them more of a normal life. Studies have shown that this type of device reduced hospitalization rates for heart failure and improved exercise tolerance and quality of life,” Chelu said.
The device was approved by the FDA in 2019. It works by improving the heart muscle contractile function. This helps to improve heart function, over time improving size, shape and function of the heart muscle. The device sends electrical pulses five to seven hours a day, in one-hour treatments separated by regular intervals without causing muscle to contract. This differs from a pacemaker in which every electrical signal leads to heart muscle contraction.
The device, created by Impulse Dynamics, is made up of several components, including an implantable pulse generator, battery charger, programmer and software. It is implanted using minimally invasive techniques, under the skin in the upper left or right area of the chest and connected to two energy-delivering leads that are implanted in the heart. The procedure typically lasts one hour and most patients can go home on the same day.