24 July 2013
Echocardiographic (ECG) screening is often used to assess people with a family history of sudden death or hereditary diseases affecting the heart and some experts have argued that population-wide screening could be useful for detecting asymptomatic heart problems.
However, a new study suggests extending such screening to the general population would have little benefit in terms of identifying structural heart disease.
Researchers at the University of Tromso in Norway studied 6,861 middle-aged people, approximately half of whom were placed in a screening group and were given a cardiac ECG test, while the others were not screened.
In particular, they wanted to see whether people who were screened had a reduced risk of cardiovascular disease and improved long-term survival, compared with the control group.
Among patients who were screened, 8.9 per cent (290 patients) had abnormal ECG findings and were referred for follow-up examinations, with 7.6 per cent (249 individuals) found to have cardiac or valvular problems.
However, the study authors noted that diagnosing asymptomatic disease is only useful "if it can lead to clinical action that slows or stops progression of disease".
"Although sclerosis of the aortic and mitral valves has been associated with a substantial increased risk of cardiovascular disease, we did not find that early diagnosis of valvular disease in the general population translated into reduced risk of death or cardiovascular events," they revealed.
The study participants were followed for 15 years to enable the researchers to evaluate the long-term benefits of population-wide screening.
During that time, 26.9 per cent of people who were screened and 27.6 per cent of people who were not screened died.
The researchers found no significant differences in the rates of sudden death, death from heart disease, or the incidence of fatal or non-fatal heart attack or stroke.
While the cardiac ECG test has an important role to play in ruling out structural abnormalities in high-risk patients and those with worrying symptoms, the latest study suggests it should not be rolled out as a routine screening test for low-risk individuals, particularly as structural heart disease is relatively uncommon in the general population.
Writing in the journal JAMA Internal Medicine, the study authors concluded: "This supports existing guidelines that echocardiography is not recommended for cardiovascular risk assessment in asymptomatic adults.
"Although our results were negative, we believe that they are of clinical importance because they may contribute to reducing the overuse of echocardiography."
Writing in an accompanying commentary, Drs Erin Michos and Theodore Abraham, from the Johns Hopkins University School of Medicine in the US, observed that critical evaluations of any screening test look at whether or not the test detects a disease process early; whether any intervention is more effective if applied early; whether the test improves outcomes; and whether it causes any harm.
They commented: "Given the low prevalence of structural heart disease in the general population, the number needed to screen is high, and the findings of the Tromso study suggest that early intervention for preclinical disease did not improve outcomes."
Posted by Edward Bartel
Health News is provided by Adfero in collaboration with Spire Healthcare. Please note that all copy above is ©Adfero Ltd. and does not reflect views or opinions of Spire Healthcare unless explicitly stated. Additional comments on the page from individual Spire consultants do not necessarily reflect the views or opinions of other consultants or Spire Healthcare.