Researchers say a common heart condition could be linked to thousands of cases of sudden cardiac death around the world.
A research team from the University of Adelaide analysed more than 7,600 studies and found that 12 per cent of victims of sudden cardiac death without a clear cause had mitral valve prolapse.
Mitral valve prolapse, a condition that alters the leaflets of the valve that let blood flow from one chamber of the heart to another, affects 12 in every 1,000 people worldwide.
For those who have the condition, blood flow between the heart’s chambers is difficult. Rather than closing smoothly and evenly, the leaflets of the valve bulge (prolapse) upward into the left atrium of the heart.
The study’s lead researcher Dr Rajiv Mahajan, Cardiologist at the University of Adelaide’s Centre for Heart Rhythm Disorders, said the findings, published in medical journal Heart, are the first to conclusively link mitral valve prolapse to sudden cardiac death.
“Over the years, there have been several case studies associating mitral valve prolapse with unexplained sudden cardiac death, however the link had not been confirmed,” Mahajan said.
“Our analysis confirms the association, and indicates that the incidence of sudden cardiac death in patients with mitral valve prolapse is significant at 14 in 1000 per year.”
The findings do not indicate that everyone who has mitral valve prolapse will die from sudden cardiac death. Indeed, many people living with the condition do so without symptoms or the need for treatment.
“The research has however enabled us to identify a number of consistent features found in cases of sudden cardiac death where the patient had mitral valve prolapse,” Mahajan said.
“Presence of scarring of the heart muscle, cases of severe bulging of both leaflets of the mitral valve, and heavy mitral valve leakage have all been reported in patients with mitral valve prolapse who have been resuscitated from cardiac arrest, which suggest patients with these features are at high risk.”
In response to their findings, the research team is creating a prospective registry in Australia for patients with mitral valve prolapse, resuscitated cardiac arrest and reported sudden cardiac death.
Heart disease is one of the leading causes of death worldwide. Figures recorded in 2015 show coronary artery disease accounted for 8.8 million deaths around the world.
Common risk factors for heart-related conditions include high blood pressure, high cholesterol, smoking, obesity and family history.