CAD is a narrowing or blockage of the arteries and vessels that provide oxygen to the heart. It is caused by atherosclerosis, a build-up of fatty material (plaque) on the lining of arteries. This narrows the blood vessel and restricts blood flow to the heart, often causing chest pain (angina). When the blood flow is completely cut off, a heart attack (myocardial infarction) occurs. CAD is the most common type of heart disease and the leading cause of death in both men and women in the U.S.
With today’s medical advances, many cases of CAD can be diagnosed and treated with a minimally invasive technique called cardiac catheterization. More than 5,000 “cath” procedures (angiograms, angioplasties, and stent placements) are performed a year in MMC’s state-of-the-art cardiac catheterization lab, making it one of the highest-volume facilities in New England.
To diagnose CAD, a heart specialist called an interventional cardiologist inserts a thin, flexible tube (catheter) into an artery in the leg or arm. The doctor then advances the catheter to the arteries in the heart, injects a special contrast dye through the catheter, and x-ray images are taken of the heart’s blood vessels to detect any blockages or other abnormalities. This is called a coronary angiogram.
When a narrowing or blockage of the arteries is found, the interventional cardiologist may perform one or both of these procedures to treat CAD:
Angioplasty – A tiny, deflated balloon is placed on the tip of the catheter and threaded through blood vessels to reach the narrowed or blocked artery. When the balloon is inflated, it pushes the plaque against the artery wall, creating a wider path for blood to flow to the heart.
Stent Placement – Sometimes a stent is placed in the artery during angioplasty. A stent is a small mesh “scaffold” that is used to prop open narrowed or weakened arteries. Notably, MMC has been involved in national clinical trials of newer drug-eluting stents. These stents are coated with a drug that dramatically reduces restenosis (the build-up of scar tissue at the site of the stent that can cause the artery to narrow again).
Open Heart Surgery for CAD – Another option for some patients with CAD is open heart surgery. In order to bypass the blocked section of coronary artery, the cardiac surgeon reroutes the blood flow through a new section of blood vessel. This new vessel is usually taken from an artery in the arm or wrist, or a vein in the leg. MMC was among the first hospitals in the nation – and the first in Maine – to perform bypass surgery in 1972, and today our surgeons perform nearly 1,000 of these open heart surgeries annually.