Stem Cell Therapy Lowers Heart Failure Risk Following Heart Attack

The largest trial conducted so far indicated that individuals who received a stem cell infusion right after a heart attack had a lower risk of developing heart failure compared to those who underwent standard treatment. This finding offers compelling evidence that stem cells may aid in the heart’s self-repair mechanisms.

Following a heart attack, the heart muscle sustains permanent damage and weakness, rendering the organ unable to adequately pump blood to meet the body’s needs, frequently resulting in heart failure. Presently, the only available treatments are heart transplants or pumps that can restore heart function.

To explore solutions, researchers turned to stem cells, which possess the remarkable capability to transform into various cell types. Nonetheless, prior studies evaluating their application post-heart attack have yielded inconsistent results. A 2020 study with 375 participants showed that bone marrow-derived cells, which include stem cells that evolve into blood cells, did not notably decrease mortality compared to standard therapies such as cardiac rehabilitation and medications aimed at lowering blood pressure, preventing blood clots, and managing cholesterol levels.

Armin Attar and colleagues from Shiraz University in Iran explored a different strategy. They employed mesenchymal stem cells capable of differentiating into structural cells such as cartilage and adipose tissue. These stem cells are also known to release substances that mitigate inflammation and promote tissue regeneration.

The researchers collected mesenchymal stem cells from umbilical cord blood and administered them into the hearts of 136 patients within three to seven days following their first heart attack. While these stem cells can also be extracted from the individual’s own adipose or bone tissue, the cultivation process can take up to a month. By utilizing umbilical cord blood samples, the team can provide treatments more swiftly and potentially enhance their efficacy, Attar explained. Another group of 260 participants received standard post-heart attack treatments.

After three years, individuals who received the stem cell therapy were, on average, 57% less likely to develop heart failure and 78% less likely to be hospitalized for heart failure compared to those receiving standard treatment. Furthermore, they exhibited significant improvements in cardiac function, suggesting that the therapy aids in the regeneration of heart tissue post-injury.

“This represents a significant advancement,” Attar remarked. Although the therapy did not lower mortality risk during the study period, the reduction in hospitalizations is still significant, according to Hina Chowdhury from the Icahn School of Medicine at Mount Sinai in New York. “Heart failure is the predominant cause of hospital admissions in the U.S.,” she pointed out.

However, it should be noted that 80% of participants were male, leading Chaudhry to caution that it is uncertain how the therapy would affect women, who are more prone to heart failure post-heart attack. Attar’s team did not observe any gender differences in a separate analysis. This study was also restricted to young adults, with all participants aged between 18 and 65. “It’s beneficial to see distinctions among age groups, as younger individuals typically have enhanced regenerative abilities and recover better from cardiac injuries,” Chaudhry noted.

This research provides the most robust evidence to date that stem cells can aid in restoring heart function post-heart attack. Nevertheless, this treatment does not fully heal the heart. “There is no medication or treatment that can replace lost heart muscle cells,” Chaudhry emphasized. Still, she added, “This ongoing work is expanding our understanding of the heart’s regeneration process and how to achieve it.”