An invasive cardiologist is a doctor who specializes in using diagnostic and therapeutic tools that are inserted directly into the patient's body to treat heart disease. These tools can include balloons, catheters and stents. Opening the body to perform heart surgery, however, is not considered a method of invasive cardiology.
All cardiologists are trained in both invasive and non-invasive methods, but will usually specialize in one type of cardiology. Non-invasive cardiology focuses on imaging techniques, such as radiology.
Cardiac catheterization is used in conjunction with other medical techniques to diagnose and treat cardiovascular problems. A cardiologist inserts a long tube (catheter) into a blood vessel on a patient's arm or leg, then threads it through to the heart, so medical procedures can be performed.
In balloon angioplasty, which is used to treat coronary artery disease, a cardiologist inserts a catheter with a small deflated balloon at the end into a patient's artery. The cardiologist then inflates the balloon to compress plaque against artery walls, allowing blood to flow more freely.
Stent procedures are typically performed alongside balloon angioplasty. A stent, which is a tiny, mesh-like device, is inserted into an artery blocked with plaque. When the stent expands, it keeps the artery open, ensuring proper blood flow.
As of 2008, more than half of American cardiologists practice invasive cardiology. The specialty now has its own medical journal through the American Heart Association.