Current smoking, as well as higher levels of cumulative cigarette exposure from past smoking, were both associated with higher left ventricular mass, a higher LV mass-to-volume ratio, and worse diastolic function in an elderly community-based population with no overt indications of coronary artery disease or heart failure, according to a report published online Sept. 13 in Circulation: Cardiovascular Imaging.
“These findings suggest that smoking is associated with subtle alterations in LV structure and function, which might help explain the higher risk of heart failure [HF] reported for smokers, independent of coronary artery disease [CAD],” said Wilson Nadruz Jr., MD, of the cardiovascular division, Brigham and Women’s Hospital, Boston, and his associates.
They analyzed links between smoking and echocardiographic features using data from the Atherosclerosis Risk in Communities (ARIC) study, an ongoing prospective observational study involving community-dwelling adults who were aged 45-64 years at baseline in 1987-1989. For their study, Dr. Nadruz and his colleagues assessed echocardiographic images taken for 4,580 ARIC participants at follow-up roughly 25 years later. None of these adults had any indication of CAD or HF; 287 (6.3%) were current smokers, 2,316 (50.5%) were former smokers, and 1,977 (43.2%) never smoked.
Compared with never smokers, current smokers showed a greater LV mass index (80.4 vs. 76.7), a greater LV mass-to-volume ratio (1.93 vs. 1.83), and a higher prevalence of LV hypertrophy (15% vs. 9%), as well as a higher prevalence of concentric LV hypertrophy and worse LV diastolic function. The same association was found between never smokers and former smokers who had higher levels of cumulative cigarette exposure, the investigators said (Circ Cardiovasc Imag. 2016 Sep 13. doi: 10.1161/circimaging.116.004950).
This association between smoking and altered LV structure and function remained robust after the data were adjusted to account for numerous cardiac risk factors such as older age, higher BMI, diabetes, hypertension, greater alcohol consumption, and higher heart rate. It also didn’t vary by patient sex, race, or income level. In contrast, there was no association between smoking and right ventricular structure or function.
“These data suggest that smoking can independently lead to thickening of the heart and worsening of heart function, which may lead to a higher risk for heart failure, even in people who don’t have heart attacks,” Dr. Nadruz said in a statement.
Looking at the results in a more positive light, senior author Scott D. Solomon, MD, professor of medicine at Harvard University, Boston, said “The good news is that former smokers had similar heart structure and function, compared with never smokers,” suggesting that “the potential effects of tobacco on the myocardium might be reversible after smoking cessation.”