Prevalence of episodes of ST-segment depression among mild-to-moderate hypertensive patients in northern Italy: The Cardioscreening Study

OBJECTIVESTo assess the prevalence of episodes of ST-segment depression in a population of consecutive patients with mild-to-moderate essential hypertension who are free of clinical signs of coronary artery disease. METHODSThe study involved 28 Italian centers that enrolled 414 hypertensive patients (aged 50–70 years; diastolic blood pressure ≥ 95–115 mmHg or systolic blood pressure ≥ 150–220 mmHg, or both, 10 days after withdrawal of medications). Silent myocardial ischemia was assessed by means of exercise stress testing and 48 h Holter monitoring. An ischemic episode was defined as a horizontal or downward sloping ST-segment depression ≥ 100 μV, occurring 80 ms after the J point, and lasting for at least 1 min. RESULTSOf the 414 patients enrolled, 411 completed the exercise stress test. During the test significant ST segment depression occurred for 25 patients (6.1%) and all episodes but one were asymptomatic and not associated with arrhythmias. Of the 396 patients for whom we analyzed a 48 h Holter recording, 43 (10.9%) had at least one episode of ST-segment depression and seven of these had also had one during the exercise stress test. The median number of episodes per patient was five (range 1–19), median duration was 9 min (range 1–20 min), and the mean amplitude of the ST-segment depression was 190 ± 180 μV. None of these episodes was associated with symptoms and all of them occurred under resting condition. Patients with (n = 61) and without (n = 335) ST-segment depression during Holter monitoring or exercise stress testing had similar ages (59 ± 6 versus 58 ± 6 years) and did not differ for tobacco smoking, plasma lipid levels, blood pressure values and prevalence of echocardiographic left ventricular hypertrophy (57% of patients had left ventricular mass indexes ≥ 134 g/m for men and ≥ 110 g/m for women in both groups). Women had a higher prevalence of ST-segment depression than did men during Holter monitoring [32 of 183 (17.5%) versus 11 of 213 (5.2%)], whereas the prevalences of ischemia during the exercise stress test were similar. Female sex was the only significant factor associated with the occurrence of silent myocardial ischemia [odds ratio 2.56 (95% confidence interval 1.40–4.71)]. CONCLUSIONSOur results show that 15% of patients with mild-to-moderate hypertension, who are free of clinical signs of coronary artery disease, experience episodes of ST-segment depression during Holter monitoring or exercise stress testing. Most of these ep