Over 1.5 million heart attacks occur every year in the United States alone, and more than 800,000 people die yearly due to heart disease. However, a new device could be key in preventing the steps that lead to heart disease after a heart attack.
'Therepi' is a small device researchers hope can stop heart attacks from causing further scarring and blockage (and ultimately valve failure). The device has a reservoir that attaches directly to damaged heart tissue. The device connects to a port under the patient's skin where therapies could be injected by the patient themselves or a nurse.
The Therepi device was developed through a collaboration between researchers from MIT, Harvard University, Royal College of Surgeons in Ireland, Trinity College Dublin, Advanced Materials and BioEngineering Research (AMBER) Centre, and National University of Ireland Galway.
"After a heart attack we could use this device to deliver therapy to prevent a patient from getting heart failure."
"After a heart attack we could use this device to deliver therapy to prevent a patient from getting heart failure," said Ellen Roche, co-first author of the study and assistant professor at MIT's Department of Mechanical Engineering and MIT's Institute for Medical Engineering and Science. "If the patient already has some degree of heart failure, we can use the device to attenuate the progression."
Common systems to deliver heart therapies are often invasive and not effective. One way to deliver drugs is by administering them systematically rather than directly to the damaged tissue. More often than not, only a small bit of the drug reaches the heart tissue. That's exactly what Therepi could avoid, the researchers explained.
"From a pharmacological point-of-view, it's a big problem that you're injecting something that doesn't stay at the damaged tissue long enough to make a difference," said William Whyte, co-first author and PhD candidate at Trinity College Dublin and AMBER.
Therepi's reservoir is made from a gelatin-based polymer, and could be the future of more effective drug delivery. The reservoir has a semi-spherical shape with a flat bottom that sits on the diseased tissue. That flat part has a semi-permeable membrane that can be tweaked to allow for more or less of a drug dosage to reach the heart tissue.
"The material we used to construct the reservoir was crucial. We needed it to act like a sponge so it could retain the therapy exactly where you need it," noted Whyte. "That is difficult to accomplish since the heart is constantly squeezing and moving."
The team tested Therepi in rats, and the device proved powerful in boosting cardiac performance after a heart attack. The researchers gave the rats several doses of cells to a damaged heart and studied them over four weeks. They then noted the changes through a pressure-volume catheter and echocardiograms.
"We saw that the groups that had our device had recovered some heart function," said Claudia Varela, a PhD student in the Harvard-MIT Division of Health Sciences and Technology.
Therepi could help in more areas
Therepi could do more than just treat heart disease, the team said. It can one day be used to deliver a variety of drugs to multiple areas, and it would give doctors better control as to the dosage they provide patients.
"As a pharmacist by training, I'm really excited to start investigating what the best dose is, when is the best time to deliver after a heart attack, and how many doses are needed to achieve the desired therapeutic effect," explained Whyte.
And the team's leadership already expects it to move beyond the realm of cardiovascular health, as Varela noted in a statement.
"The device is really a platform that can be tailored to different organ systems and different conditions," said Varela. "It's just a great example of how intersectional research looking at both devices and biological therapies can help us come up with new ways to treat disease."