Analysis and Interpretation of the Electrocardiogram
Hypokalemia
Hypokalemia is associated with progressive ST depression, progressive flattening or inversion of the T waves, the development of U waves, increased amplitude and duration of the P waves and QRS complexes as well as a slight increase in the duration of the PR interval. Furthermore, hypokalemia affects automaticity of the pacemaker cells and leads to multiple arrhythmias such as sinus bradycardia, atrioventricular block, atrial flutter and Torsades de Pointes. Most commonly, hypokalemia results from thiazide diuretic misuse, diarrhea, renal or adrenal disease. Other causes include infusion of large amounts of glucose or alkali substances, liver cirrhosis and diabetic coma.