Dr. Charles "Pat" Davis, MD, PhD, is a board certified Emergency Medicine doctor who currently practices as a consultant and staff member for hospitals. He has a PhD in Microbiology (UT at Austin), and the MD (Univ. Texas Medical Branch, Galveston). He is a Clinical Professor (retired) in the Division of Emergency Medicine, UT Health Science Center at San Antonio, and has been the Chief of Emergency Medicine at UT Medical Branch and at UTHSCSA with over 250 publications.
Dr. Shiel received a Bachelor of Science degree with honors from the University of Notre Dame. There he was involved in research in radiation biology and received the Huisking Scholarship. After graduating from St. Louis University School of Medicine, he completed his Internal Medicine residency and Rheumatology fellowship at the University of California, Irvine. He is board-certified in Internal Medicine and Rheumatology.
Percutaneous coronary intervention is a non-surgical method used to open
narrowed arteries that supply heart muscle with blood (coronary arteries).
Percutaneous means "through unbroken skin." Percutaneous coronary intervention
is performed by inserting a catheter through the skin in the groin or arm into
an artery. At the leading tip of this catheter, several different devices such
as a balloon, stent, or cutting device (artherectomy device) can be deployed.
The catheter and its devices are threaded through the inside of the artery back
into an area of coronary artery narrowing or blockage.
The "I" in percutaneous
coronary intervention is for "Intervention," which means that even if the person
is actively having a heart attack (myocardial infarction or MI), percutaneous
coronary intervention can be used to intervene and stop the attack by opening up
the narrow or blocked coronary artery. This allows blood to flow to the heart
Percutaneous coronary intervention began as percutaneous transluminal coronary angioplasty (PTCA), a
term still found in the literature, and now encompasses balloons, stents (metal
scaffolding expanded inside the artery lumen), and other modifications to the
catheter tip, including devices that can cut out plaque and thus open up the
narrowed artery. Although treatment of acute heart attack is a very important
use of percutaneous coronary intervention, it has several other uses.
Percutaneous coronary intervention can be used to relieve or reduce angina,
prevent heart attacks, alleviate congestive heart failure, and allows some
patients to avoid surgical treatment (coronary artery bypass graft or CABG) that
involves extensive surgery and often long rehabilitation time.
Coated stent: Also known as a medicated stent. A tiny cage coated with a drug to prop open an artery and prevent it from closing again. The stent is a minute metal mesh tube. It is inserted into a coronary artery usually just after an angioplasty has been done to open the vessel. The stent slowly releases the drug with which it is coated. The drug may, for example, be sirolimus. Coated stents reduce the risk of artery re-narrowing, or restenosis,
after angioplasty which occurs about a third of the time when bare metal stents