Young women who are not at risk for a cardiac event can experience a spontaneous heart attack which occurs suddenly rather than after a slow build-up of plaque over time.
SCAD or Spontaneous Coronary Artery Dissection is a poorly understood condition. So far, it is still impossible to predict the genes and environmental triggers that result in coronary arteries spontaneously tearing or dissecting. This leads to a life-threatening heart attack that requires emergency medical care.
Recently, researchers were able to identify the genetic clues that can give us a better understanding of SCAD. A team led by Santhi Ganes, M.D. from the Michigan Medicine Frankel Cardiovascular Center have identified the difference between SCAD and the common heart attack called atherosclerosis.
According to Ganesh, the SCAD risk alleles were inversely associated with coronary disease and myocardial infarction due to atherosclerotic disease. This suggests that the biology underneath the diseases are very different. He adds that while many of the same genetic markers are involved, they are involved in different ways.
The team of researchers performed a genome-wide association study and analysed millions of genetic markers in patients with SCAD. They found a significant association of several specific genetic regions associated with SCAD, implicating specific genes influenced by the identified genetic variants.
Furthermore, the team reports that the genetic risk factors for SCAD also predict SCAD among people with FMD or fibromuscular dysplasia. FMD is a vascular disease that can affect any artery in the body and can occur in patients with SCAD. Similar to SCAD, individuals with FMD also don’t have the traditional risk factors associated with atherosclerosis such as high blood pressure and diabetes. However, they are at risk for vascular complications like arterial aneurysms and dissections.
It is also interesting to note that, as discovered by the study, the SCAD risk alleles are positively associated with migraine headache. This highlights a shared genetic basis for SCAD and migraine headache. However, more research is needed to precisely define the biological relationship between SCAD and the mentioned conditions as well as its implications.
Ganesh says that the unbiased and large-scale study is able to provide new clues to further the research on SCAD. Co-lead author Jacqueline Saw, M.D. from Vancouver General Hospital/ University of British Columbia adds that the identification of the risk alleles will improve our understanding of the risks of SCAD.
The next step of the research is to conduct analyses on larger groups of patients with SCAD and conduct further in-depth studies of the genetic and biologic relationship between SCAD and FMD as well as related dysplasia-associated arterial diseases. Ganesh’s team is also launching a clinic and genetic study of postpartum SCAD.