Heart rate variability reveals risk of arrhythmias after intoxication with antidepressants

Excerpt

We demonstrate here for the first time how monitoring of depressed heart rate variability (HRV) after intoxication with tricyclic antidepressants (TCA) may be a valuable marker of the cardiac autonomic nervous system function and can help identify patients who are at risk for developing cardiac arrhythmias. A 28-year-old man was admitted to the ICU at 3:20 a.m., 3 h after taking 9.2 g trimipramine and 7.35 g amitriptyline in a suicide attempt. His blood pressure was 140/70 mmHg and heart rate 105–135 bpm. He remained conscious and was breathing spontaneously with a respiration rate of 12–18/min, maintaining an oxygen saturation of 98%. The initial electrocardiogram showed widening of the QRS complex to more than 150 ms and a prolonged QTc interval of 522 ms, which immediately improved after intravenous administration of 100 ml 8.4% sodium bicarbonate and 2 mg physostigmine salicylate [1]. Plasma levels were elevated at 831 ng/ml for trimipramine and 733 ng/ml for amitriptyline. Initial treatment included short-term intubation for a gastric lavage with 140 l fluid followed by multiple doses of activated charcoal, a single administration of magnesium sulfate, and intravenous fluid replacement. …