Effects of pinacidil on the heart: Serial electrocardiographic and echocardiographic observations

In a prospective, double-blind study comparing pinacidil to hydralazine in mild systemic hypertension, 33 patients were followed with serial echocardiograms and electrocardiograms. There were four study groups: pinacidil and hydralazine (long-term therapy), and pinacidil and placebo (short-term therapy). There were no significant changes in mean echo LV mass or in LV systolic function in any of the groups. One patient in each group developed LVH de novo despite decreases in blood pressure. Four patients receiving pinacidil therapy (23%) developed new T-wave abnormalities and in 1, the initially abnormal T waves returned to normal at follow-up. Seven of 9 T-wave abnormalities were minor (Minnesota Code) and were not associated with any echocardiographic abnormality. One patient in the placebo group also developed new minor T-wave abnormalities. One patient receiving pinacidil therapy who had new major T-wave abnormalities developed cardiac ischemia. There were no other cardiac events.