Effects of hyperbaric exposure on mechanical and electronic parameters of implantable cardioverter-defibrillators

Hyperbaric oxygen therapy (HBOT) is the standard adjuvant treatment for life-threatening or disabling pathologies. Currently, mechanical and electronic variations of implantable cardioverter-defibrillators (ICD) in hyperbaric conditions have not been evaluated. As a result, many patients eligible for HBOT but ICD recipients cannot undergo this therapy, even in emergency situations.

Twenty-two explanted ICD of various brands and models were randomized in two groups: single hyperbaric exposure at an absolute pressure of 4000 hPa and 30 iterative hyperbaric exposures at an absolute pressure of 4000 hPa. Mechanical and electronic parameters of these ICD were blindly assessed before, during, and after hyperbaric exposures. Regardless of the hyperbaric exposure, we could not find any mechanical distortion, inappropriate occurrence of anti-tachycardia therapies, dysfunction of tachyarrhythmia therapeutic programming, or dysfunction of programmed pacing parameters.

Dry hyperbaric exposure seems harmless on ICD tested ex vivo. This result may lead to a reconsideration of the absolute contraindication of emergency HBOT to ICD recipients. A real-life study in these patients with an indication to HBOT should be performed to assess their tolerance to the treatment.