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Updated: Aug 15, 2026

Rodent Working Heart Model for the Study of Myocardial Performance and Oxygen Consumption
Published on: August 16, 2016
Effects of desipramine on autonomic input to the heart
B T Walsh1, L L Greenhill, E G Giardina
1Department of Psychiatry, College of Physicians and Surgeons, Columbia University, New York, USA. btw1@columbia.edu
Objective:
To examine the impact of age on the effects of desipramine (DMI) on autonomic input to the heart.
Method:
Twenty-four-hour electrocardiograms were obtained from 42 subjects, aged 7 to 66 years, while off and on DMI. To obtain measures of autonomic input to the heart, heart rate variability was assessed via spectral analysis of RR interval variability.
Results:
DMI treatment was associated with a significant increase in 24-hour mean heart rate and significant decreases in RR interval variability in all spectral bands, including in the high-frequency band, which provides a measure of parasympathetic input to the heart. RR interval variability was greater in younger individuals both off and on DMI.
Conclusions:
DMI treatment was associated with a marked decline in RR interval variability, indicating that DMI affects autonomic input to the heart. Specifically, DMI reduced parasympathetic input, which, in theory, may increase vulnerability to arrhythmias. However, the magnitude of DMI's impact on RR interval variability did not vary with age.
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