Role of Heart Rate Variability in Predicting Post-Endoscopic Retrograde Cholangiopancreatography Pancreatitis

Introduction : Early recognition of post-ERCP pancreatitis (PEP) would help deliver an appropriate discharge plan following ERCP. Functioning of the autonomic nervous system can be measured using non-invasive heart rate variability techniques (HRV) and provides quantitative information about the modulation of cardiac vagal and sympathetic activity. Pain evoked sympathetic activation is a well-known phenomenon, as exhibited in those suffering PEP. The aim of this study is to determine if a single post-procedural measurement of HRV identifies those at risk of developing PEP. Methods : A prospective, observational, single-centre cohort study was performed including all patients undergoing either diagnostic or therapeutic ERCP. In addition to standard monitoring electrocardiographic (ECG) signals 4 hours post- ERCP were recorded using a digital ECG. Results : A Total of 115 patients were enrolled over 11 months. PEP occurred in 12 (10.4%) patients. The low frequency (LF)/ high frequency (HF) ratio on HRV was significantly higher in those suffering PEP (median LF/HF 2.58 vs 2.10, p<0.001). It is possible to identify patients at high risk of PEP through HRV analysis where the LF/HF ratio is found to exceed 2.43, with an AUC of 0.827 and combined sensitivity of 83.3 % and specificity of 81.6 % (PPV 42%, NPV 97%). Conclusions : In this first study of HRV analysis in those undergoing ERCP the index of sympathovagal balance (LF/HF) predicted PEP independently of other risk factors. This could lead to the use of post procedural HRV to identify patients suitable for early discharge following ERCP. (Acta gastroenterol. belg., 2016, 79, 429-434).