Prevalence of silent ST segment depression during long-term ambulatory electrocardiographic monitoring in asymptomatic diabetic patients with essential hypertension

: Thirty-five asymptomatic diabetic patients with non insulin-dependent diabetes and mild moderate essential hypertension (18 males and 17 females, mean age 60 +/- 6 years) underwent echocardiographic examination, followed by simultaneous ambulatory blood pressure and electrocardiographic monitorings. Three hundred and sixteen significant episodes of asymptomatic ST segment depression (at least 1 mm 80 msec after the J point, lasting more than 1 min) were recorded in 21 patients (60%) with a total duration of 5637 minutes. Patients with asymptomatic episodes of ST segment depression had significantly higher values of total cholesterol (p < 0.05), LDL cholesterol (p < 0.05), Glycosylated hemoglobin (p < 0.001), left ventricular mass index (p < 0.02), mean 24-hour systolic and diastolic ambulatory blood pressure (p < 0.001), systolic (p < 0.02) and diastolic (p < 0.01) ambulatory blood pressure variability and hypertensive peaks (p < 0.05), with respect to the rest of the study population. The number of ST segment depression episodes was significantly related to total cholesterol levels (r = 0.40, p < 0.05), LDL cholesterol levels (r = 0.36, p < 0.05) glycosylated hemoglobin levels (r = 0.50, p < 0.01), left ventricular mass index (r = 0.48, p < 0.01), ambulatory systolic (r = 0.43, p < 0.01) and diastolic (r = 0.51, p < 0.01) blood pressure variability and hypertensive peaks (r = 0.50, p < 0.01). Our data suggest that haemodynamic and metabolic factors could have a relevant role in high prevalence of SMI in asymptomatic diabetic patients with EH. The evidence of SMI in these patients warrants further diagnostic work-up and prognostic assessment.