​Differential diagnosis of ischemic causes of negative U wave on ECG are : 
-Prinzmetal’s angina 
-coronary heart disease
-exercise induced ischemia
-angina 
-myocardial infarction 

​Differential diagnosis of non ischemic causes of negative U wave on ECG are : 
-pulmonary embolism 
-long QT syndrome 
-left ventricular hypertrophy 
-right ventricular hypertrophy 

​Differential diagnosis of negative U wave on ECG are : 
-non ischemic causes
-ischemic causes

​Differential diagnosis of drugs causing high U wave on ECG  are : 
-quinidine 
-procainamide
-digitalis 

​Differential diagnosis of high U wave on ECG are : 
-cardiomyopathy 
-hypokalemia 
-bradycardia 
-high vagal tone 
-hyperthyroidism 
-diabetes mellitus 
-left ventricular hypertrophy 

​Differential diagnosis of high T wave on ECG are : 
-chronic phase of myocardial infarction 
-Prinzmetal’s angina 
-normal variant 
-acute perimyocarditis 
-complete left bundle branch block 
-increase left ventricular strain 
-left ventricular hypertrophy 
-hyperkalemia 
-acute hemopericardium 
-vagotonia 

​Differential diagnosis of terminally negative T wave on ECG are : 
-intoxication 
-rheumatic 
-neoplastic infiltration 
-perimyocarditis 
-myocarditis 

​Differential diagnosis of pre terminal negative T wave on ECG are : 
-digitalis 
-pericarditis 
-left ventricular hypertrophy 
-congestive heart disease

​Differential diagnosis of flattened / low T wave on ECG are : 
-myocarditis 
-hypothyroidism 
-Addison’s disease
-hypocorticism 
-hypokalemia 
-congestive heart disease
-myocardial ischemia 
-anterior myocardial infarction 
-cardiomyopathy 
-pericardial effusion 
-sympathicotonia 

​Differential diagnosis of negative T wave on ECG are : 
-hyperventilation 
-juvenile T wave pattern 
-digoxin effect 
-left ventricular hypertrophy with strain 
-right ventricular hypertrophy with strain 
-myocardial contusion 
-myocarditis 
-pericarditis 
-myocardial infarction 
-myocardial ischemia 
-subarachnoid hemorrhage 
-intermittent left bundle branch block 
-dilated cardiomyopathy 
-post pacemaker T inversion 
-post tachycardia T inversion 
-idiopathic apical hypertrophy