REN and Hypertension: The lesser decrease in systolic blood pressure on the old-drug combination is probably the consequence of the β–blocker-induced reduction of heart rate, which is responsible for a later return of the reflected waves in the central arteries during systole and more pronounced systolic augmentation.23, 24 Furthermore, under treatment with inhibitors of the renin system, but not under treatment with β-blockers, the structural arteriolar abnormalities associated with hypertension regress.