Hans Åberg

Metabolic effects of a change in antihypertensive treatment

Twenty hypertensive men, aged 58 to 62 years, who had been treated with a combination of different drugs for many years, had their therapy changed in a stepwise manner to a combination of 50 mg of atenolol per day and 2 to 15 mg of prazosin per day. The effects of each change of treatment were assessed separately five to six months after the change. Serum lipids and high-density lipoprotein concentrations were determined, and an intravenous glucose tolerance test was performed at the start of the study and after each change. In the group in which therapy was changed from a diuretic to prazosin, serum cholesterol and triglyceride concentrations decreased significantly by 11 and 42 percent, respectively, but in the group in which therapy was changed from hydralazine to prazosin, there were no alterations in serum lipids or lipoproteins. The changes in therapy had no overall effects on glucose or insulin parameters evaluated with an intravenous glucose tolerance test. However, prazosin was associated with an increase in the fasting blood glucose level and a decrease in the peak insulin value after glucose injection, both of which were dose-related effects. The data indicate that the glucose turnover was at least as good after a switch from diuretic to prazosin treatment as before at lower insulin values. In those patients in whom therapy was switched from propranolol to 50 mg of atenolol per day, the serum triglyceride concentration decreased by about 10 percent, whereas in the group in which therapy was changed from 100 to 50 mg of atenolol per day, there were no serum lipid or lipoprotein alterations. The results show that a combination of 50 mg of atenolol per day and prazosin has metabolic advantages over combined diuretic and propranolol treatment. Such advantages may be of importance in the long-term treatment of hypertensive patients.

Atrial Activity during Exercise in Patients with Atrial Flutter or Atrial Fibrillation

The atrial activity was studied at rest and during exercise in 6 patients with atrial flutter and in 7 patients with atrial fibrillation. In the latter, a special recording technique was used which permitted identification of the f-waves. No increase in the frequency of the atrial waves was found. Thus the increase of the ventricular rate during work in patients with atrial flutter or atrial fibrillation seems to be caused by a change in the atrio-ventricular conduction.

Electrocardiographic Changes in 50-Year-Old Men with Different Levels of Diastolic Arterial Blood Pressure

An ECG study of P wave abnormalities and signs of left ventricular hypertrophy (LVH) was performed in a series of 76 50-year-old men with hypertension detected in a population study. Two control groups were obtained from the same study. P wave abnormalities were common (36/76) among the hypertensives but were frequently seen also among the controls (41/152). Thus it seems that P wave abnormality, with the current criteria, is not a reliable early sign to discriminate hypertensives from persons with a normal blood pressure. High QRS voltage or left axis deviation was not uncommon in the control groups, while any combination of at least two criteria of LVH (high voltage, prolonged ventricular activation time, ST-T changes or left axis deviation) was far more common in the hypertensive group. In cases with high voltage as the single criterion of LVH examination of the P wave may be helpful to discriminate hypertensives from persons with a normal blood pressure.