Texas Heart Institute at St. Luke’s Episcopal Hospital First in Nation to Implant Heart Pump in Study to Assess Device’s Potential to Limit Heart Muscle Damage after Heart Attack
Interventional cardiologists affiliated with Texas Heart® Institute (THI) at St. Luke’s Episcopal Hospital (St. Luke’s) recently implanted the first two patients in the nation with a tiny heart pump in a feasibility trial to determine the pump’s potential to limit damage to heart muscle following a heart attack.
The FDA-approved trial will assess whether use of the Impella® 2.5 pump for 24 hours after a patient has undergone angioplasty to open a blocked coronary artery may limit the area of heart muscle damage, known as infarct size. Enrolled patients must have suffered a STEMI—ST-elevation myocardial infarction—the most serious form of heart attack.
THI at St. Luke’s was the first among a maximum of five sites approved to enroll a total of 60 patients in the feasibility trial. If successful, the feasibility study could expand to a larger trial.
Darlene Davis, a 49-year-old Houston resident, was the first patient enrolled in the trial on September 14 at St. Luke’s. Her day began routinely as she was cleaning her mother’s house and fixing breakfast before heading to work at a car rental business. Davis suddenly began to feel pressure and a “funny” pain in her back that started moving from her left side to her chest.
Davis’ brother drove her to a nearby fire station. Once there, paramedics determined that she was having a heart attack. An ambulance was soon taking Davis to St. Luke’s in the Texas Medical Center, where she was taken directly to the Cardiac Catheterization Laboratory.
Twenty-eight minutes after Davis’ arrival, Leo Simpson, MD, performed a successful angioplasty to re-establish blood flow to her heart. Minutes after the procedure, Guilherme Silva, MD, and the clinical research team presented the opportunity to participate in the study to Davis. She agreed to participate in the clinical trial and was immediately implanted with the heart pump.
Andrew Civitello, MD, implanted the pump in the second patient, a 54-year-old man, at St. Luke’s on September 20.
“This trial may have significant implications for the 250,000 patients who have a STEMI in the U.S. each year,” Dr. Civitello said. “Many of these patients develop progressive heart failure from damage suffered during a heart attack.”
“By resting the heart with the Impella pump during a major heart attack, we hope to limit the damage done to the heart,” he added. “If successful, the procedure should ultimately lead to improved survival and quality of life after a STEMI.“
The Impella is billed as the “world’s smallest heart pump” by its developer, Abiomed Inc. It received FDA approval in 2008 for partial circulatory support. A physician inserts the pump with a catheter through a small opening in a patient’s groin, threads it through the femoral artery and eventually into the left ventricle of the heart. The pump then pulls blood from the left ventricle through an inlet area in the pump’s tip and expels blood from the catheter into the ascending aorta.
THI at St. Luke’s was chosen as a site for the trial based on the cardiologists’ extensive experience implanting the pump for other purposes, including in high risk patients while undergoing angioplasty and in conjunction with ablations of the left ventricle. An ablation is a procedure used to treat abnormal heart rhythms.
By “unloading” pooled blood from the left ventricle, the pump decreases the pressure inside the left ventricle and results in better perfusion, which is the delivery of oxygenated blood and nutrients from the heart,” Dr. Silva said. “This gives the left ventricle a rest. You can think of it as allowing the left ventricle to put up its feet for a little while.”
Scott Sherron, MD, co-chair of St. Luke’s STEMI Committee, noted that previously, cardiologists were only able to affect infarct size by the speed of their response to open a blocked artery.
“Time is muscle,” Dr. Sherron said. “But now we may have a tool that we can use in addition to opening the artery, which would be a great addition to our toolbox for treating heart attacks.”