Experimental Heart Failure Treatment Shows Promise
But experts caution that larger studies of combined treatment are needed
That's a "decent" improvement, said Dr. Eduardo Marban, director of the Cedars-Sinai Heart Institute in Los Angeles. And it's possible it could translate into long-term benefits -- like a lower risk of a repeat heart attack or longer life, according to Marban.
But, he said, larger studies are needed to prove that.
"This is a feasibility and efficacy study," Marban explained. He added that neither shock waves nor bone marrow cells are approved treatments for heart failure. "You're not going to be able to go to your doctor and ask for this."
Dr. Gregg Fonarow, a professor of cardiovascular medicine and science at the University of California, Los Angeles, agreed that caution is in order.
"Whether these findings can be reproduced, and whether there is any clinical benefit that will result from this approach, will require subsequent, well-designed clinical trials," said Fonarow.
The findings are based on 103 patients who'd developed chronic heart failure after a heart attack. Zeiher's team randomly assigned 81 patients to receive shock wave therapy; afterward, 42 of them received an infusion of bone marrow cells, while 39 were given a cell-free "placebo" infusion.
The remaining 21 patients received placebo shock wave therapy. (A cushion was placed over the chest so the ultrasound waves could not reach the heart.) They did, however, get a real infusion of bone marrow cells.
Four months later, patients who'd received the combination therapy were faring best: On average, the percentage of blood being pushed out of the heart's main pumping chamber ticked up 3 percent.
That's "modest," the researchers acknowledged, but it compared with no significant change in the other patients.
The combination-therapy group also had fewer heart-related "events," such as heart rhythm problems, hospitalization for heart failure, repeat heart attacks or strokes. There were 32 such complications among the 42 patients, versus 18 among the 21 patients who received only bone marrow cells.
Now, one of the big questions is whether the improved heart function fades with time, Zeiher said. Repeat treatments may be necessary.
"In principle," Zeiher said, "that can be very easily performed, because the procedure itself is rather simple and -- most importantly -- safe."