Scientists have found that this experimental pig treatment alters the scar tissue that forms after a heart attack. Although the extent of scarring is the same, the structure changes, allowing for better recovery.
In case of heart attack, the heart muscle is damaged, leading to the formation of this scar tissue. As a result, even when people survive the attack, their ability to pump blood is reduced.
Existing medical responses today attempt to restore blood flow – and thus oxygen – to the heart as soon as possible after an attack. This reduces scarring, but since attacks rarely occur when medical technology is at hand, it often comes too late to prevent long-term damage. Heart failure occurs within a year after almost a quarter of the patients' first attack.
According to IFLScienceJames Chong of the University of Sydney, Australia administered an intravenous infusion of platelet-derived growth factor rhPDGF-AB to 36 pigs for seven days.
A month later, animals receiving this growth factor had better heart function and a 40% increase in survival rate, the scientist said in the study. published in the journal Science Translational Medicine.
Speaking to this site, Chong explained that the team was initially surprised by the results because, although cardiac function clearly improved, the volume of scar tissue had not changed.
Using advanced microscopy techniques, the researchers found that the pig's scar tissue had "chaotic and disorganized" collagen fibers. But for the pigs that received rhPDGF-AB, the fibers were aligned.
Although the team is still unsure why the aligned scar tissue works so much better, Chong said it "helps in the transmission of viable heart muscle on both sides and also aids in the formation of blood vessels." Together they allow the heart to continue to function relatively normally even in the event of induced shocks.
The team had also achieved similar results in guinea pigs, but the good thing here is that the pig's heart is very similar to ours. Therefore, the next step will be to conduct human clinical trials, although the university still needs investment to do so and complete some specific safety tests.
However, the main outstanding issue is how quickly, after a heart attack, treatment begins to be effective. The pigs used in this research received it immediately after induced attacks. As this will not be possible with people, delay time can be a crucial factor.