Title : Autonomic dysfunction resulting in Inappropriate Sinus Tachycardia (IST) after Roux-en-Y gastric bypass.
Abstract:
A 27year old female with a history of Roux-en-Y gastric bypass, complicated by gastrojejunal anastomotic stricture resulting in Wernicke’s encephalopathy due to thiamine deficiency was admitted to our service for persistent tachycardia, palpitations, symptomatic orthostatic hypotension, dizziness and shortness of breath at rest. She had no history of cardiac disease or cardiac arrhythmia prior to her surgery. Her resting heart rate was 138. Since the surgery, she lost around 130 lbs within a span of 7 months. Her tachycardia worsened with activity. Initial ECG showed a borderline shortened PR interval of 116ms with questionable delta wave concerning for WPW (Wolff-Parkinson-White (WPW) syndrome) (Figure 1). After a careful EP evaluation, WPW was ruled out. Her rhythm was determined as Sinus tachycardia with borderline shortened PR interval. Her 2D Echo showed normal LVEF of 60-65% with mild mitral and tricuspid regurgitation. Her condition was thought to have been initiated by rapid profound weight loss causing autonomic dysfunction resulting in IST/POTS (Inappropriate Sinus Tachycardia/ Postural orthostatic tachycardia syndrome). She also developed severe new-onset peripheral neuropathy post-surgery and underwent a complete neurological workup that included a lumbar puncture which ruled out autoimmune/post-infectious neuropathy. Her Multiple sclerosis panel, copper level, VDRL & Oligoclonal bands were all normal.
We started her on metoprolol 12.5 BID, florinef 0.2mg QD, midodrine 10mg QID, Ivabradine 7.5mg BID and Propranolol 10mg TID providing good symptom relief. She underwent aggressive physical therapy and was placed on supplemental Folic acid and thiamine as well.Autonomic dysfunction is quite common after bariatric surgery. It occurs more frequently after gastric bypass surgery. Profound rapid weight loss is believed to be a contributing factor. This patient had a complication with her gastric bypass surgery that required several dilations of her jejunum in the past which further worsened her vitamin deficiencies. It is important to discuss cardiac side effects with candidates interested in gastric bypass surgery.
Audience Take Away Notes
- Autonomic dysfunction caused from profound rapid weight loss after bariatric surgery.
- Cardiac comorbidities to be considered before rapid weight loss surgery.
- Educate patients for signs and symptoms for IST/POTS after rapid profound weight loss.
- Resting tachycardia in a patient must be evaluated thoroughly, especially after weight loss surgery.
