<prompt> All the following are the electrocardiographic features of hyperkalemia exceptProlonged PR intervalProlonged QT intervalSine wave patternLoss of P waves  <response>: Hyperkalemia pro- duces a sequence of changes , usually beginning with nar- rowing and peaking tenting of the T waves. Fuher elevation of extra- cellular K leads to AV conduction disturbances, diminution in P-wave Ref Harrison 20th edition pg 1421 amplitude, and widening of the QRS interval. 