Symptomatic Bradycardia: A Rarely Reported Manifestation of Crohn's Disease Flare-up and Mesalamine Use

Background:
Inflammatory bowel disease (IBD), including Crohn’s disease and ulcerative colitis, has been known to cause a variety of gastrointestinal manifestations as well as extra-intestinal manifestations. Extra-intestinal manifestations are reported to affect 20-30% of patients with Crohn’s disease resulting in cutaneous, ophthalmic, musculoskeletal, and hepatobiliary symptoms. Cardiovascular manifestations are less frequently noted but may arise in patients with no prior cardiac history and complicate management of acute Crohn’s disease flare-ups.
Methods:
Patient is a 44-year-old female with history of Crohn’s disease who presented to the emergency department for bloody stools and abdominal pain for the past several days. Patient was diagnosed with Crohn’s disease 6 years ago and symptoms had progressively worsened during this time. Patient had been prescribed azathioprine in the past but was unable to take due to lack of insurance. CT abdomen was ordered and was unremarkable. Patient was started on intravenous methylprednisolone and mesalamine 4.8 grams daily for Crohn’s flare-up. On initial admission, patient presented with a heart rate of 69. However, within 24 hours of admission, patient presented with new-onset lightheadedness and dizziness. For the next few days, patient presented with symptomatic bradycardia with heart rates decreasing to 32 beats per minute. Cardiac workup was initiated, and EKG showed sinus bradycardia. Transthoracic echocardiogram showed EF of 55-60% and was otherwise unremarkable. Over the next 5 days, patient’s heart rate improved to the 60s as her Crohn’s flare-up improved.
Results:
While Crohn’s disease is classically associated with gastrointestinal symptoms, extra-intestinal symptoms including uveitis/episcleritis, enteropathic arthritis, cholelithiasis, and urolithiasis may be noted. Less frequently, the inflammation associated with Crohn’s disease can result in a range of cardiovascular manifestations including arrhythmias, atrioventricular block, myocarditis, pericarditis, and heart failure. In patients with Crohn’s disease, there is a low reported incidence of cardiovascular manifestations, but these manifestations have a higher incidence than the general population. Symptomatic sinus bradycardia in patients with no prior cardiac history has rarely been reported in the literature. Additionally, mesalamine use has rarely been reported as a cause of bradycardia and should be considered in any patient presenting with new-onset bradycardia not related to drugs such as beta blockers or calcium channel blockers. Only a few clinical cases have ever been reported in the literature and these generally occurred among younger women with bradycardia presenting within a short period of time following administration of mesalamine. Due to the frequent use of mesalamine for treatment of ulcerative colitis and Crohn’s disease, the risk of bradycardia should be considered prior to starting treatment. Regular monitoring of patients following mesalamine administration can prevent adverse effects related to symptomatic bradycardia.
Conclusions:
Crohn’s disease management is complicated by the wide range of gastrointestinal and extra-intestinal manifestations that may be associated with the inflammatory processes of IBD. Crohn’s disease flare-ups with associated mesalamine use may present with new-onset symptomatic bradycardia as a rarely-reported side effect. As a result, monitoring for cardiovascular manifestations of Crohn’s disease flare-ups and mesalamine use is recommended.