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By Lawrence M. Prescott, Ph.D.
Because of the numerous major advances in the techniques,
devices, and medications used in percutaneous coronary
intervention (PCI), a 2005 update of the 2001
Guidelines for Percutaneous Coronary Intervention was
jointly released by the American College of Cardiology,
the American Heart Association, and the Society for
Cardiovascular Angiography and Interventions at a special
briefing during the American Heart Association Scientific
Sessions 2005 held in Dallas in mid-November.
"These guidelines have applications and implications
far beyond the practice of interventional cardiology,"
said William W. O'Neill, M.D., Corporate Chairman of
Cardiology for the William Beaumont Hospital System in
Royal Oak, Michigan. "It's imperative that physicians and
hospital administrators review the guidelines, because
they may be used to grade performance."
Percutaneous coronary intervention encompasses a wide
variety of procedures used to treat patients with blocked
coronary arteries. Typically, PCI is performed by
threading a balloon-tipped catheter from the femoral
artery in the groin to the blockage in the coronary
artery. The balloon is then inflated to open the artery
and an expandable metal stent often placed to keep the
artery open.
In the four years since the 2001 revision of the PCI
Guidelines, there have been dramatic advances.
Drug-eluting stents that not only keep the artery open but
also release medication that prevents scar tissue
overgrowth were not even commercially available in 2001.
"The use of drug-eluting stents is rapidly changing the
treatment of coronary artery disease," stated Ted Feldman,
M.D., Professor of Medicine, Northwestern Medical School,
Chicago, Illinois, and Director of the Cardiac
Catheterization Laboratory, Evanston Hospital, Evanston,
Illinois. "These guidelines address the real-world issues
that are important to the use of drug-eluting stents."
Additional highlights of the guidelines include:
Recommendations for Institutional and Annual
Operator Volume: PCI procedures should be performed by
experienced physicians who perform more than 75 elective
PCI procedures per year and at least 11 PCI procedures on
heart attack patients at high-volume centers.
Anatomic Indicators: It is reasonable to perform
PCI on patients who have significant coronary artery
disease of the left main coronary artery but who are not
eligible for bypass surgery. Careful post-procedural
surveillance should include a post PCI angiogram at two to
six months post-procedure as part of the follow-up.
Onsite Surgical Facilities for Elective Angioplasty:
Elective PCI should not be performed at institutions that
do not have onsite cardiac surgery facilities.
Use of Distal-Protection Devices: While these
devices require further study, it is recommended that
distal embolic protection devices be used whenever it is
technically feasible in patients who are undergoing PCI to
saphenous vein grafts transplanted to the heart during
coronary artery bypass surgery.
Antiplatelet and Antithrombolytic Adjunctive
Therapies for Patients Undergoing PCI:
- All patients should be taking aspirin before PCI
procedure, whether or not already taking daily chronic
aspirin therapy.
- A loading dose of clopidogrel should be administered
before PCI is performed.
- If clopidogrel is given at the time of the
procedure, supplementation with GP IIb/IIIa receptor
antagonists can be beneficial to facilitate earlier
platelet inhibition than with clopidogrel alone.
Post-Procedural Pharmacotherapeutic Recommendations:
- In addition to risk-factor modification, all
post-PCI patients should begin taking a regimen of
aspirin and clopidogrel unless these medications are
contraindicated.
- ACE inhibitors should be considered for all patients
with coronary heart disease, left ventricular
dysfunction, or high blood pressure.
- All patients who have suffered a heart attack or
have another acute condition, such as left ventricular
dysfunction, should be given ?-blockers for at least six
months, unless there are contraindications.
- Diabetic patients need glucose-lowering therapies
that will bring their HbA1c levels to less than 7%.
- Aggressive lipid lowering therapy, reducing
low-density lipoprotein cholesterol (LDL-C) to less than
70 mg/dL is recommended as an optional target for very
high risk patients.
Finally, one of the key recommendations in the updated
guidelines concerns the goal of PCI: to restore blood flow
to the heart muscle within 90 minutes of the patient's
arrival at the hospital.
"It is an aggressive goal," said Sidney C. Smith, Jr.,
M.D., who headed the guideline writing committee and is
Professor of Medicine and Director, Center for
Cardiovascular Science and Medicine, University of North
Carolina, Chapel Hill, North Carolina. "The science shows
that patients truly benefit from 'a door-to-balloon time'
of 90 minutes or less. We have consistently looked at
where the science says we should be, and challenged
ourselves."
This update on
the new percutaneous coronary intervention (PCI)
guidelines released at the American Heart Association
Scientific Sessions 2005 was written by Lawrence M.
Prescott, Ph.D. He may be contacted via e-mail at
sprescott@aol.com. |