ECG findings in Hypokalemia

  T wave flattens.

 
U wave amplitude increases. The prominent U waves may become taller than the T waves.

      When
the U wave merges with the T wave, it may give the appearance of QT interval prolongation.

 
ST segment depression.



Clinical significance

  In patients under Digoxin therapy, hypokalemia predisposes to Digoxin induced arrhythmias.

  In patients with Long QT Interval Syndrome (LQTS), hypokalemia predisposes to Torsades de Pointes.




References (with links to sample ECGs)

  Chou's Electrocardiography in Clinical Practice. Adult and Pediatric.

      5th ed. Philadelphia. WB Saunders. 2001.

  Perm J 2012;16(2):57.

  Am J Emerg Med 2014 Mar;32(3):286.e1-4.

  Ann Noninvasive Electrocardiol 2013;18(6):593-596.

  J La State Med Soc 2015;167(3):140-141.

  Ann Noninvasive Electrocardiol 2014;19(4):387-390.

  Intern Emerg Med 2012;7(2):193-194.

  BMJ Case Rep 2012 Sep 30;2012.

  J Travel Med 2012 Mar-Apr;19(2):124-126.

  Tidsskr Nor Laegeforen 2011;131(4):358-360.

  J Gen Intern Med 2013;28(9):1242-1246.