Blood flows differently through the hearts of men and women, according to new research.
Scans have identified dramatic variations in its movement through the left ventricle – the organ’s main pumping chamber.
Men’s hearts have to work harder and exert more energy there in order to move blood through the organ, whereas women’s blood swirled more violently and the ventricle’s wall showed more signs of strain – patterns scientist think are linked.
The finding could shed light on gender inequalities in cardiovascular disease care that are costing lives, the University of Wisconsin, Madison authors believe.
Advance ‘4D’ MRI scans show how blood moves through the left (red) and right (yellow) ventricles of the heart.Differences the University of Wisconsin team found between men and women may explain why heart disease affects the sexes differently
Heart disease is the leading of death for American men and women alike, but the exact types of cardiac conditions affect each group differently.
And from their observations, doctors believe these differences are explicable not just by the differences in the size and shape of male and female human hearts, but in their structural mechanics, and how blood moves through them.
Kinetic energy, for instance, the force spent during contraction and filling of the muscle, was significantly higher in the left ventricles of men.
Vorticity, on the other hand, a measure of regions of rotating flow that form during different points of the cardiac cycle, was greater in women.
There was also more strain – an indicator of left ventricular function, reports Radiology: Sportstoto Cardiothoracic Imaging.
The study used a sophisticated technique called 4D flow MRI (magnetic resonance imaging).
It offered striking visuals of blood flow in the heart and vessels of 20 men and 19 women.
When these were compared with cardiac function there were significant differences between the sexes.
The results could be used to help create quantitative standards that adjust for gender to provide improved assessment of heart performance.
Differences in the hearts of men and women have long been known. Women’s are smaller in size and beat faster than men’s, on average.
But much less is known about the way that blood flows through the hearts of men and women – and how that relates to cardiac health.
Lead author Dr David Rutkowski, Singapore Pools of the University of Wisconsin, Madison, said: ‘Using the MRI data, we found differences in how the heart contracts in men and women.
‘There was greater strain in the left ventricle wall of women and a higher vorticity in the blood volume.We hypothesize these two things are related.’
The study and the methods it employed have a number of potential applications,he said.