Does silent myocardial ischaemia detected by Holter monitoring predict death or myocardial infarction in healthy middle-aged and elderly subjects with no previous heart disease?
Silent myocardial ischaemia detected by Holter monitoring in healthy older adults without known heart disease identifies a high-risk subgroup for future cardiac events.
AIMS: We aimed to determine the prevalence and prognostic significance of daily-life silent myocardial ischaemia (SMI) in healthy middle-aged and elderly subjects with no previous heart disease. METHODS AND RESULTS: Six hundred and seventy-eight healthy men and women between 55 and 75 years of age and with no history of cardiovascular disease or stroke were included. Baseline examinations included physical examination, fasting laboratory testing, and 48 h ambulatory electrocardiogram monitoring. An episode of ischaemia was defined by a down-sloped or horizontal ST depression of at least 1 mm at a duration of at least 1 min. Seventy-seven subjects (11.4%) had SMI. All participants were followed for up to 5 years. In 77 subjects with SMI, 16 (20.7%) had an event (death or myocardial infarction). In 601 subjects without SMI, 50 (8.3%) had an event. The hazard ratios for SMI in relation to cardiac and combined events after correction for conventional risk factors were 3.1 (1.24-7.97), P=0.016 and 1.97 (1.06-3.69), P=0.033, respectively. CONCLUSION: SMI as detected by Holter monitoring was detected in 11.4% of these subjects and was associated with more than three-fold increase in the cardiac event rate after correction for risk factors, implying that this test could be used to identify high-risk individuals among these subjects.
Sajadieh et al. (Thu,) studied this question.