Use of Theophylline to Avoid Permanent Pacing in Post Heart Transplant Sinus Node Dysfunction.

Abstract

Introduction: Post-operative sinus node dysfunction can occur in patients following orthotopic heart transplantation (OHT), requiring temporary or permanent pacing. Theophylline (TH) has been used as a pharmacologic alternative in such patients. Methods: This study retrospectively evaluated 60 patients who underwent OHT from 2008 to present. 27 patients were treated for sinus bradycardia (defined by heart rate < 85 beats per minute). One patient died within 60d of OHT and was excluded. 20 patients (group A) were administered TH alone and 6 (group B) were administered TH and temporary pacing. Heart rates during the 24 hours prior to the start of TH, at 7d following the start of TH, during the 24 hours following discontinuation (DC) of TH, at 30d and 60d after DC of TH, and during the patient's most recent hospital visit were analyzed. Additionally, the duration and doses of treatment with TH were obtained. Results: Patients in group A (4 women & 16 men) were started on TH an average of 7d post OHT for a mean duration of 28d with a median dose of 400mg. Statistically significant differences from 24 hour post OHT heart rates were noted compared to average heart rates at 7d post initiation of TH (p=.002), in the 24 hours following DC of TH (p<.001), at 30d post initiation of TH (p<.001), at 60d post initiation of TH (p=.001), and at the most recent measurement (median = 521d post OHT) (p=.004) (table 1). Group B, on temporary pacing at 8d pre-TH, consisted of 2 women and 4 men. TH was started an average of 9d post-OHT for a mean duration of 33d with a median dose of 400mg. Pacing was discontinued after a mean of 8d. Heart rates and treatment profiles are shown in table 1.Table: No Caption available.Conclusions: Our results indicate that TH can be instituted to effectively increase heart rate in patients with post-OHT sinus bradycardia. Sinus node dysfunction usually improves over a period of weeks to months and early use of TH could increase heart rate sufficiently to delay or eliminate the need for permanent pacing after OHT.