When Damaged Hearts Struggle to Heal

Photo from Olivier Collett on Unsplash
Photo from Olivier Collett on Unsplash

By analysing a certain protein that forms new blood vessels following a heart attack or unstable angina the long term-survival of heart patients could be predicted.

The study, published in PLOS ONE, has shown the presence or absence of a gene variant for the protein (vascular endothelial growth factor [VEGF]-A) can help predict the long-term survival chances in males who have experienced an acute coronary event.

Dr Barry Palmer of the Massey University School of Health Sciences said that the human body’s ability to recover from severe health events such as heart attacks is aided by its capacity for new blood vessel creation.

“Measuring an individual’s ability to restore blood circulation after a serious, life-threatening health event, may be useful in choosing treatment options and timing of specialist or GP visits. It may also have implications for susceptibility to other complex diseases, such as cancer.

“We showed testing for a VEGF-A gene variant from a patient’s blood was a useful predictor of how long these patients survived after their heart disease event. This association was most obvious in non-diabetic patients.”

The study reported on 1927 patients from the Coronary Disease Cohort Study in New Zealand, of which 30 percent had at least one previous episode of serious heart disease.

In a subgroup, the researchers also investigated the utility of measuring VEGF-A protein itself from 550 heart patients.

It has long been known that VEGF-A plays a role in helping cancer tumours to grow by increasing their blood supply, Dr Palmer said.

“In the heart disease field, it’s been suggested that high levels of VEGF-A might be a good thing to help grow new blood vessels around clogging or blocked arteries. The research so far has led to some controversy with some reports showing that more VEGF-A in the bloodstream is associated with better outcome in heart disease.

“While others, including our study, show high levels of VEGF-A after a heart event is linked to worse outcomes. An explanation for this could be that high VEGF-A levels may signal hearts under stress struggling to restore heart function, but not always rescuing function enough to save badly damaged hearts,” Dr Palmer added.

“High levels of VEGF-A in the blood may be being churned out to try and grow new blood vessels in a badly damaged heart, but may not be enough for the patients with the most damaged hearts. About 40 percent more of patients with high VEGF-A are dying within eight years of their original admission to hospital.

“After adjusting for seven other relevant measurements, patients with 10-fold higher levels of VEGF-A, measured shortly after their health event, had approximately twice the risk of death during the follow-up period.”

Source: Massey University