Value of a specific bradycardic agent in cardiac surgery compared to placebo

The effects of alinidine on systemic and pulmonary haemodynamics and the ECG were studied in 8 patients early after open heart surgery as a double-blind cross-over comparison between alinidine and placebo. Placebo had no effect on any of the measured variables. Alinidine given as an i.v. bolus (10 mg) followed by an infusion (10 mg h-1) was associated with alinidine plasma levels of 172 +/- 17 and 114 +/- 13, respectively, (+/- SE, ng ml-1) and decreased heart rate (-12%) and rate-pressure product (-14%) in all patients. While stroke volume index tended to increase, there were no changes in arterial, pulmonary and atrial pressures, cardiac index, and systemic and pulmonary vascular resistances. PR and QRS intervals of the ECG remained unaffected, and the QTc interval transiently decreased. Alinidine appears to be a suitable drug for control of inappropriate sinus tachycardia in patients with heart disease undergoing surgery.