EFFECTS OF ANTIHYPERTENSIVE TREATMENT ON SILENT-MYOCARDIAL-ISCHEMIA IN HYPERTENSIVES WITHOUT CORONARY HEART-DISEASE

To evaluate clinically silent S-T segment depression in hypertensives with normal coronary arteriograms, 48-hour ECG recordings of S-T segments were analysed in 25 patients (15 men, 10 women; mean age 57 ± 9.2 years) before starting antihypertensive drug therapy. Ischaemic episodes were recorded in 14 patients, ten of whom had an abnormal exercise ECG and 13 had hypertensive fundus changes. After antihypertensive drug therapy had been given for 2-3 weeks (pre-treatment blood pressure systolic 174 ± 8.5, diastolic 90 ± 5.4 mm Hg; post-treatment 132 ± 12.9/77 ± 8.3 mm Hg) the number of ischaemic episodes per 48 hours fell significantly from 219 to 113 (P < 0.05), the median of ischaemic episodes decreased from 16 to 5 per 48 hours (P < 0.05), and the median of maximal S-T segment depressions from 1.6 to 1.2 mV (P < 0.05). These results indicate that S-T segment analysis of long-term ECG monitoring is a suitable method for demonstrating silent ischaemia in hypertensives, and danger of ischaemic attacks in hypertensives is reduced by effective antihypertensive drug treatment.