According to a study, researchers examined wearing a lightweight vest equipped with a cardioverter defibrillator that detects abnormal heart rhythms in addition to taking recommended medications is associated with a reduction in the likelihood of dying during the first 90 days following a heart attack in people whose heart function was also impaired.

People who wore the wearable cardioverter defibrillator (WCD) during the study timeframe were 35% less likely to die for any reason compared with those who received medications alone. While the study did not find a significant benefit regarding reducing sudden cardiac death, the primary endpoint.

The study did find that the wearable defibrillator was associated with fewer overall deaths. "But the cause of death is irrelevant if we can prevent it. This study found that the device was associated with fewer deaths among people recovering from a heart attack with low ejection fraction.

It's also the first therapy associated with a mortality benefit above and beyond standard medical therapy immediately after a heart attack." The three-month mortality rate for people recovering from a heart attack which also have reduced heart function is around 5%, Olgin said, and that is with optimal medical management.

Similarly, inVEST, 4.9 percent of participants in the control group died compared with only 3.2% of those wearing the WCD, an absolute difference of 1.7%. Despite the high rate of sudden death in the months following a heart attack, implantable cardioverter defibrillators (ICDs) placed in the chest aren't currently indicated for this patient population before 40-90 days for several reasons.

First, large studies have failed to show that implanting an ICD during this period results in long-term reductions in mortality.  Second, in many cases, someone's ejection fraction will improve in the ensuing months' post-heart attack. According to Olgin, these new findings suggest WCDs could fill the gap in cardiac therapy until patients can be evaluated for an ICD.

Current guidelines recommend the WCD as a potential tool that practitioners can use, but the researchers believe findings from this large randomized trial will add important data to inform these guideline recommendations further. The vast majority of patients in both groups upwards of 85% received appropriate guideline-directed treatment for post-heart attack management.

Even heart failure management gave patients' reduced ejection fraction. At the end of the study, researchers searched the National Death Index for participants lost to follow up. The rate of cardiovascular-related re-hospitalizations was 25% and was similar in both groups.

Researchers are working on much additional analysis from this study. They also plan on transitioning patients into a registry for longer-term follow up.