Hyperbaric oxygen therapy reduces the risk of QTc interval prolongation in patients with diabetes and hard-to-heal foot ulcers

Aims: Heart rate corrected QT (QTc) interval prolongation is a risk factor associated with increased mortality. Hyperbaric oxygen therapy (HBO) has previously been shown to have acute beneficial effects on QTc dispersion. The aim of this study was to evaluate long-term effects of HBO on QTc time in diabetic patients with hard-to-heal foot ulcers. Methods: In a prospective, double-blinded placebo-controlled study, patients were randomized to 40 treatment sessions with either HBO or air (placebo), at 2.5 ATA. Patients fulfilling >35 completed treatment sessions were included in the evaluation. Results: Of the initial 75 patients (38 HBO/37 placebo), two were excluded due to pacemaker use. Baseline characteristics were similar between groups. At the 2-year follow-up, QTc time was significantly shorter in the HBO compared to the placebo group (438 vs. 453 ms, p < 0.05). Further, fewer HBO treated patients had a QTc time >450 ms (22 vs. 53 %, p < 0.02). This difference seemed to be caused by a significant prolongation of the QTc interval in the placebo group (427 (419-459) at baseline vs. 456 ms (424-469) after 2 years), whereas no significant change was seen in HBO treated patients. Conclusions: HBO treatment might protect against QTc prolongation in this high-risk diabetic population. (C) 2015 Elsevier Inc. All rights reserved.