Echocardiography Not a Useful Predictor of Heart Disease and Heart Failure in Asymptomatic Individuals

The use of echocardiography as a screening tool for structural and valvular heart disease among the general population showed no benefit in the reduction of mortality, nor did it reduce the risk of myocardial infarction (MI) or stroke, according to results from a recent study [JAMA Intern Med. 2013;173:1592-1598]. Haakon Lindekleiv, MD, PhD, University of Tromsø, Tromsø, Norway, and colleagues conducted a study to examine whether echocardiographic screening for structural heart disease in the general population improved long-term survival or reduced the risk of cardiovascular disease (CVD).

The study consisted of 6861 participants, taken from the population-based Tromsø study, which focused on CVD. Participants were randomized to either an echocardiographic screening group (n=3272) or a control group (n=3589). The primary outcome measure was all-cause mortality; secondary outcome measures were sudden death, death from heart disease, and fatal and nonfatal MI and stroke. Participants were followed up for 15 years, between 1994 and 2009.

The researchers collected information on baseline cardiovascular risk factors and medication use via self-reported questionnaires and physical examination. A total of 290 participants had a follow-up that included complete medical history, clinical examination, transthoracic echocardiography, resting and exercise electrocardiography, and if necessary, transesophageal echocardiography.

Exploratory analyses of the risk of death from all causes were performed in 6 predefined subgroups: participants with hypertension, participants with diabetes mellitus, participants with a family history of early MI, and participants with low, moderate, and high cardiovascular risk profile.

Of the 290 participants referred for follow-up, cardiac or valvular pathologic conditions were verified in 249. Results showed that during the 15 follow-up years, 880 participants (26.9%) in the screening group and 989 participants (27.6%) in the control group died (see Table below). The researchers found no statistically significant differences between groups in terms of primary or secondary outcome measures. Adjusting for possible confounding factors also did not alter the results.

The researchers did find that screening reduced the risk of death from all causes among those participants who had a family history of early MI, with an absolute risk reduction in mortality after 15 years of 4.7%.

“Our findings add empirical evidence to the existing guidelines for appropriate use of echocardiography, which hitherto have been based on expert consensus opinion,” Dr. Lindekleiv said.