Electrocardiogram and B-type natriuretic peptide as screening tools for left ventricular systolic dysfunction in a population-based sample of 75-year-old men and women.

BACKGROUND: Plasma concentration of B-type natriuretic peptide (BNP) has been suggested as a powerful screening tool for left ventricular systolic dysfunction. However, there are reports indicating that the 12-lead electrocardiogram (ECG) could be just as powerful. We aimed to evaluate the 12-lead ECG and BNP as screening tools for left ventricular systolic dysfunction in an elderly, unselected population.
METHODS: In a randomly selected population-based sample of 75-year-old men and women (n = 407), diagnostic characteristics were evaluated for the ECG and plasma concentration of BNP to detect left ventricular systolic dysfunction.
RESULTS: Sensitivity, specificity, and negative and positive predictive values for the ECG to detect left ventricular systolic dysfunction were 96%, 79%, 100%, and 26%, respectively. The corresponding values for the BNP (cut-off value 28 pg/mL) were 93%, 55%, 99%, and 13%. In participants without major abnormalities in the ECG, left ventricular systolic dysfunction was found in <1% (1/302), irrespective of BNP concentrations. In participants with abnormal ECGs, systolic dysfunction was more prevalent in persons with abnormal BNP concentrations than in those with normal concentrations (35% vs 3%, difference 32%, 95%CI for the difference 16%-44%)
CONCLUSIONS: In 75-year-old subjects both the ECG and the plasma concentration of BNP are highly efficient in excluding left ventricular systolic dysfunction. However, compared with the BNP, the ECG yields a lower number of false positive cases. In screening for left ventricular systolic dysfunction, the BNP has a diagnostic value in addition to the ECG, but only in individuals with abnormal ECGs.