Over the long run, however, the policies of the one-drop rule and segregation, in conjunction with other factors such as a long tradition of racial nationalism and white liberal support, generated a counter-reaction that led to a very different form of racial politics.
Learn about these ultrasound-like tests of the heart -- and find out what to expect -- here. Cardiac Catheterization. Cardiac catheterization -- also called a coronary angiogram -- means running a catheter into your heart. It's done to help doctors see what's going on in there, and whether they need to operate. Here's where to learn about it.
The test can show your heartâs structure (muscle, valves and chambers) and how well blood flows through your heart and major vessels. MRI of the heart lets your doctor see if your heart is damaged from a heart attack, or if there is lack of blood flow to the heart muscle because of narrowed or blocked arteries.