MVA: an important global problem

As we continue to battle the Covid-19 pandemic, a little-known disease – microvascular angina (MVA) – has also been flagged as an important global health problem.

A prospective, international study recently published in the European Heart Journal has shown that chest pain cause by problems with the very small vessels supplying blood to the heart is an important health problem that increases the risk of heart attacks, stroke and death due to cardiovascular reasons.

Until now MVA has reportedly been thought of as a benign disease that mainly occurs in women; however, the study, which recruited 686 patients from 14 institutions in seven countries on four continents between July 2015 and December 2018, showed that during one to two years of follow-up until December 2019, events such as stroke, heart attack and hospitalisation for chest pain occurred in nearly 8% of patients each year.

The researchers found that men and women were almost equally affected, and the prognosis was no different according to sex or ethnicity.

“MVA is an under-researched area, partly because no definite universal definition was available before the COVADIS [COronary VAsomotor Disorders International Study] definition and partly because cardiologists are mainly interested in the large coronary arteries but not the smaller vessels that are also part of the coronary circulation,” says first author of the study and member of the COVADIS Group, Professor Hiroaki Shimokawa.

“Currently, many doctors are not aware of the importance of coronary microvascular dysfunction. As a result, many patients with MVA are misdiagnosed as having postmenopausal disorders or an imbalance of conscious and unconscious nervous system for instance.

“However, previous research has suggested that the number of patients with MVA is three to four million in USA, which is equal or greater than the number of patients with breast cancer, so it is an important global problem,” he says.

While the researchers disclose study limitations that include the absence of a reference group which to compare the results, Professor Shimokawa says that this international study “demonstrates the importance of coronary dysfunction in patients with MVA”.

“Considering the fact that coronary microvascular dysfunction is involved not only in MVA but also in other forms of cardiovascular disease, including large coronary artery disease and myocardial disease, we believe clinicians should pay closer attention to it,” says Professor Shimokawa.

To read the study, visit: academic.oup.com/eurheartj/advance-article/doi/10.1093/eurheartj/ehab282/6284114