Could this be vertigo? I have had a double bypass 3 years ago and tomorrow I am having a heart cath test. Yesterday I woke up to light headedness and my eyes were a little off. It felt like my equilibrium was off alittle bit. Today it seems a little bit b

Arrhythmia. Altered heart rhythm can cause lightheadedness and dysequilibrium... Your upcoming test will assess heart rate and rhythm...
This . This could have been a sign of dehydration, blood pressure changes, blood sugar changes, vertigo, carotid artey disease etc. If you have not done so already, you need to inform your doctor about these symptoms. He/she may want to do additional testing (i.e. Scan of your carotid arteries in your neck to look for blockage) and other diagnostic and/or blood tests. Best of luck.