A longitudinal, observational study of patients without cardiovascular disease at baseline found that the mass and volume of the left ventricle differs between men and women as they get older. The results were based on cardiac MRI taken at baseline and during a follow-up visit.
Lead researcher John Eng, MD, of Johns Hopkins University in Baltimore, and colleagues published their findings online in Radiology on Oct. 20.
After a median follow-up period of 9.4 years, the mass of the left ventricle increased 8 g per decade in men and decreased 1.6 g per decade in women. In addition, the left ventricle diastolic volume decreased 29.8 mL per decade and 213.3 mL per decade, respectively, while stroke volume decreased 28.8 mL per decade and 28.6 mL per decade, respectively.
Further, the mass-to-volume ratio increased 0.14 and 0.11 g/mL per decade, respectively.
The Multi-Ethnic Study of Atherosclerosis included 2,935 patients who enrolled at six community-based centers in the U.S. between July 2000 and September 2002. At baseline, they were between 45 and 84 years old and had no history of coronary artery disease, peripheral vascular disease, cerebrovascular disease and heart failure.
Between April 2010 and February 2012, patients had their fifth follow-up examination, during which they underwent a cardiac MRI. They had also had a cardiac MRI at baseline. The imaging was performed with 1.5-T imagers.
“We had the opportunity to re-examine the same people after 10 years so that we could see what happened to their hearts after a decade,” Eng said in a news release. “This is a more reliable way to assess left ventricular changes over time.”
At baseline, the mean age was 69 years, 53 percent of participants were women, 42.3 percent were white, 24.9 percent were black, 20.3 percent were Latino and 12.5 percent were Asian.
Compared with patients who refused cardiac imaging at the fifth follow-up, those who consented to imaging were younger and had a higher level of education. More white patients and fewer Latino patients underwent the follow-up MRI. In addition, patients undergoing the follow-up MRI had a lower systolic blood pressure, hypertension and diabetes and were less likely to have a history of smoking and more likely to exercise.
During the follow-up visit, 56.7 percent of patients had hypertension, 20.7 percent had impaired fasting glucose, 16.9 percent had diabetes, 7.5 percent were smokers and 36.8 percent were taking lipid-lowering medications.
The researchers noted that the change in left ventricle mass was positively associated with systolic blood pressure and body mass index and negatively associated with treated hypertension and high-density lipoprotein cholesterol.
“The shape of the heart changes over time in both men and women, but the patterns of change are different,” Eng said. “Men’s hearts tend to get heavier and the amount of blood they hold is less, while women’s hearts don’t get heavier.”