<prompt> J waves are seen inHypothermiaHyperthermiaHypokalemiaHyperkalemia  <response>: Hypothermia 1319-H 1389-H17thECG-Changes:Hypothermia- Associated with a distinctive convex hump at the J point Osborn waveHypocalcemia- Prolongation of the Q-T interval ST-segment portionHypercalcemia- Abbreviation of the ST segment and shortening of the QT interval.Hypokalemia- Decreased amplitude and broadening of T-wave, prominent U waves, premature ventricular contractions and depressed ST segmentsHyperkalemia- Peaked T waves of increased amplitude, widening of the QRS, and biphasic QRS-T complexes- Severe hyperkalemia causes cardiac arrest with a slow sinusoidal type of mechanism sino-wave pattern followed by asystole. CVA-T-wave pattern seen in subarachnoid haemorrhage. 