…These age variations in heart rate are due to variations in the activity of the autonomic nervous system and changes in the automaticity of the…

…This is due to altered tone in the autonomic nervous system, with increased sympathetic input (leading to stimulation of beta adrenergic receptors) and parasympathetic withdrawal…

…due to atrial fibrillation with wide QRS complexes due to bundle branch blocks or other conduction defects. However, in rare instances, it may be due…

…Due to this rapid clearance, adenosine must be administered as a rapid intravenous bolus. Unlike many other intravenous medications where rapid boluses risk hemodynamic instability…

…of the QRS complexes vary from one beat to another (in the same lead). This is due to the swinging back and forth of the…

…of the R waves. This is believed to be due to delayed (and thus electrically unopposed) depolarization in the ischemic area. Fragmented QRS complex The…

…and infarction Use of ECG in acute coronary syndromes & chest pain patients An ECG must be performed on all patients seeking medical attention due to…

…Furthermore, sudden cardiac arrests account for 50% of all years of life lost due to cardiovascular disease ( Myerburg et al ). Sudden unexpected cardiac arrest is…

…may also arise due to extensive subendocardial infarction (NSTEMI). If pathological Q waves occur as a result of myocardial infarction, the infarction may be classified…

…to infarction due to the collaterals. Occasionally, patients with total and proximal occlusions may present without ST segment elevations (which they should exhibit) due to…