The workshop "my worst arrhythmia nightmare" will include 3 case-based presentations and cover the following topics: 1) Management of patients with non sustained ventricular tachycardia and newly diagnosed dilated cardiomyopathy with severe left ventricular dysfunction. 2) Management of patients with conduction disturbances in the context of acute myocardial infarction. 3) Evaluation of patients with AV conductions disorders (limiting optimisation of medical treatment or requiring pacing), moderate LV dysfunction (35-40%) and narrow QRS. Generally there is a limited appreciation of a rational approach to these particular arrhythmia cases. This workshop will fulfill the learning needs of those seeking a practical approach to these difficult arrhythmia cases. Difficult arrhythmia cases like those addressed in this workshop are a frequent challenge to all involved in the clinical management of patients. This workshop will provide participants with a comprehensive and practical approach to difficult arrhythmia cases. Workshop participants will also learn how to interpret the ECG tracings in such cases. The CHRS education committee planned this workshop. Members of this committee include community and academic cardiologists, electrophysiologists, cardiology residents and allied professionals from diverse practices and experience across Canada. The CHRS education committee is composed of representatives from each of the following regions: British Colombia, Prairies, Ontario, Quebec, Atlantic Provinces. The CHRS education committee has developed an objective and balanced representation of the topic of "difficult arrhythmias" that is completely free of third-party influence and/or support. Of note, 8 previous "My worst arrhythmia nightmare" workshops have been held at CCC (2011-2018). All of these were well attended and highly successful with plenty of interaction and discussion. For the past 3 years our workshop was selected for an exploratory workshop format. Even with this new format involving the performance of our workshop 3-times in a row, our workshop was well-attended at each of the sessions. Over the years, the topics included covered a plethora of difficult situations in arrhythmia management that are relatively frequently encountered in the practice of clinical cardiology. Based on the success of the previous workshops, the CHRS education committee have decided to plan a "my worst arrhythmia nightmare" workshop annually at CCC, in order to fulfill the learning needs of cardiologists, internists and trainees in the field of arrhythmia management. This year, the CCS congress managing team invited us to submit our session again for inclusion in the CCC 2019 Scientific Program.