You may have been taking nitroglycerin to relieve your angina, and recently your doctor has had to increase the dosage. Ventriculograms enable your doctor to visualize your left ventricle from many angles. They reveal much information about the ventricle's structure and functioning. You might have already taken other less invasive diagnostic tests such a treadmill test, an echocardiogram or a nuclear scan. Based upon the results of those tests, your history, physical examination, and symptoms, your doctor has determined that additional information is required.
Cardiac catheterization can provide that information.
Finally, you may be scheduled to undergo surgery on another part or system of your body. Your doctor has ordered a cardiac catheterization test to determine whether you have severe coronary artery disease. If so, he may want you to undergo one of two corrective procedures first. These events are rare. Discuss your current medications with your physician.