Clinical significance of minor nonspecific ST-segment and T-wave abnormalities in asymptomatic subjects: a systematic review.

The purpose of the study is to examine the prevalence and significance of minor nonspecific ST-segment and T-wave abnormalities (NSSTTA) in the prediction of future cardiovascular disease (CVD) events. Minor NSSTTA are commonly encountered in clinical practice. To date, there have been no systematic reviews focusing on the prevalence and prognostic importance of these findings. Literature searches of MEDLINE (1966-2005) were supplemented with searches of bibliographies from key articles. We focused on isolated minor NSSTTA in healthy middle-aged or elderly populations, including men, women, blacks, and whites, and the association of isolated minor NSSTTA with incident cardiovascular and coronary events. Isolated minor NSSTTA are common in middle-aged white men (ranging from 3.6% to 10.3%), and seem to be even more prevalent in women, blacks, and the elderly. In the 3 studies that examined isolated minor NSSTTA, the multivariable-adjusted hazard ratios for coronary mortality ranged from 1.24 to 1.66. Although gender, race, and age-specific differences in the prognostic significance of minor NSSTTA are not clear because of limited data, minor NSSTTA in asymptomatic patients are an important risk factor for coronary and cardiovascular mortality, independent of traditional risk factors. Minor NSSTTA are prevalent in asymptomatic individuals, and they confer increased risk for CVD and coronary heart disease (CHD), independent of traditional risk factors. Future studies with standardized methodology are needed to elucidate the physiological significance of minor NSSTTA and to further describe gender, race, and age-related differences in the prevalence and prognostic significance of minor NSSTTA.