#Pacemaker failure to capture pdf#

Six months after cardiac surgery the patient underwent a VVI pacemaker implant (Vitatron G20) for permanent atrial fibrillation with slow ventricular response. Patient underwent bivalvular mechanic mitral- aortic valve replacement 13 years ago. She had a history of type 2 diabetes mellitus and chronic kidney disease (eGFR of 12 ml/min). An 81-year-old woman was admitted to our institution with bradycardia, weakness and presyncope. We report a case where moderate hyperkalemia caused pacemaker exit block and a failure of ventricular pacemaker capture. Occasionally failure to capture appears at a lower level, especially in the presence of heart disease.

When the K level reaches 7 mEq/L pacing thresholds could increase, with or without increased latency. When the K level increases, the intraventricular conduction velocity is decreased and the paced QRS complex widens. Hyperkalemia is a life threatening metabolic condition. Our patient showed a moderate acute hyperkalemia, which caused pacemaker exit block and capture failure. Analytic test showed a creatinine 3.78 mg/dl, Urea 187 mg/dl, sodium 133 mEq/L, potassium 6.2 mEq/L, and pH 7.37. The interrogation of the device showed a correct ventricular sensing and a threshold for ventricular pacing of 6.5 V at 1 ms pulse width. At admission physical examination revealed a pulse rate of 42 per minute, blood pressure of 95/50 mmHg, and an oxygen saturation of 93% on room air.

#Pacemaker failure to capture pdf#

View PDF Download PDF Tables & Figures AbstractĪn 81-year-old woman was admitted to our institution with bradicardia, weakness and presyncope. Related article at Pubmed, Scholar Google This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited. (2015) Failure of Ventricular Capture and Pacemaker Exit Block Secondary to Moderate Hyperkalemia. Moderate Hyperkalemia Pau Alonso *, Raquel Lopez, Maria Jose Sancho-Tello, Ana Andres, Oscar Cano, Joaquin Osca and Jose Olagueĭepartment of Cardiology, Electrophysiology Section, La Fe University Hospital, Valencia, SpainĮlectrophysiology Section, La Fe University HospitalĮ-mail: OctoAccepted: NovemPublished: November 28, 2015Ĭitation: Alonso P, Lopez R, Sancho-Tello MS, Andres A, et al. Possibility of lead displacement has to be considered, which is more likely with temporary pacing.Failure of Ventricular Capture and Pacemaker Exit Block Secondary to In the setting of evolved inferior wall infarction, it is likely that temporary pacing was done for complete heart block, which has now resolved into first degree AV block. Inhibited mode means that a sensed impulse will inhibit the pacing. Usually demand pacemaker waits for a pause in the basic rhythm before firing as it senses the spontaneous rhythm and works in inhibited mode. Early occurrence again indicates sensing failure. Rhythm strip shows two additional pacing spikes with ventricular captures, also occurring fairly early after the previous QRS complex. Though it has not captured the ventricles, it does not mean capture failure as it has occurred within the QT interval of the previous QRS complex when we expect the ventricles to be refractory. The premature occurrence indicates sensing failure. The pacing artefact marked by red arrow has occurred prematurely and has failed to capture the ventricles. The premature occurrence of the pacing spike would indicate a sensing failure of the pacemaker. The spike marked with blue arrow has come a short while after the preceding QRS complex and has captured the ventricles causing a wide QRS complex.

Multiple pacemaker spikes or pacing artefacts are visible. The interesting part is evident in the rhythm strip. What are the findings in this ECG and possible explanations?ĮCG shows PR interval prolongation, Q and ST elevation with T inversion in lead III, small q and T inversion in aVF along with lateral ST depression and T wave inversion indicating an inferolateral myocardial infarction with first degree AV block.