C.A. 81 years old female patient with end stage renal disease (unknown etiology) on haemodialysis treatment from 01/06/1996. Her body weight was 43 Kg. She had remarkable osteoporosis and normal-low Parathyroid hormone (adynamic bone disease?). Other co-morbidities: peptic ulcer disease, diverticulosis, transient ischemic attack some years ago, and notably, neither cardiac disease nor hypertension reported.
Med list: Epogen 8000 units/week iv. Renvela 800mg bid, Omeprazole 20 mg daily, paracetamol 1000 mg daily
After taking (first time in her life!) 50 mg of tramadol (for bone pain) at bed time she experienced malaise and vomiting. On arrival at hemodialysis unit (30 April 2013) she had low blood pressure (90/60), nausea, vomiting, weakness, palpitations and sweating. Interdialytic weight gain was only 0,8 Kg. Blood gas analysis showed normal acid-base and normal electrolyte
Basal EKG (A in figure) showed normal sinus rhythm with bradycardia at 55 bpm, normal PR interval and narrow QRS, no repolarization abnormalities were present.
The EKG in context of vomiting crisis (B in the figure) showed a change in the duration and morphology of P wave (>120 ms and +/- morphology in inferior leads, II, III and VF –see detail in the figure-). This pattern is typical of advanced interatrial block (Bayes de Luna A., et al J Electrocardiol 1985:18:1, Baranchuk A. et al Europace 2013:15:1822 )
Bicarbonate-dialysis was performed. Note that K+ and Ca++ dialysate concentration were 3 mEq/L and 1,5 respectively. Session was uneventful with 1 L fluid removal. Two days later (2 May 2013) advanced IAB was disappeared (C in figure).
This is a typical case of intermittent advanced interatrial block without clear relation to changes in heart rate and probably as a consequence of some type deleterious and transient effect during vomiting crisis perhaps related with imbalance of autonomous nervous system.