Cardiovascular effects of desipramine in children and adults during exercise testing

Objective: In light of recent reports of sudden death in children being tre ated with desipramine (DMI), 3 of which were associated with physical exerc ise, the authors examined the effects of DMI on exercise in children and ad ults before and during DMI treatment. Method: Before treatment, 22 subjects (9 children, 13 adults) participated in a graded treadmill exercise test. Outcome measures included exercise tolerance, cardiovascular, and electroca rdiographic parameters at progressive intensity levels and serum norepineph rine (NE) levels before and after exercise testing. Subjects were then trea ted with DMI, titrated to an average DMI dosage of 3 mg/kg, and underwent r epeated exercise testing. Results: DMI treatment was associated with a sign ificant elevation of circulating NE levels in the pre-exercise assessment. Exercise tolerance was not affected by DMI, and blood pressure and heart ra te effects were modest. The cardiovascular impact of DMI treatment was simi lar in children and adults. One 31-year-old subject exhibited a brief episo de of ventricular tachycardia associated with exercise during DMI treatment . Conclusions: DMI has only minor effects on the cardiovascular response to exercise, and these effects do not appear age-related. However, DMI may in crease the risk of exercise-associated arrhythmias in rare individuals.