The American College of Cardiology/American Heart Association
Task Force on Practice Guidelines was formed to gather
information and make recommendations about appropriate
use of technology for the diagnosis and treatment of
patients with cardiovascular disease. Percutaneous coronary
interventions (PCIs) are an important group of technologies
in this regard. Although initially limited to balloon
angioplasty and termed percutaneous transluminal coronary
angioplasty (PTCA), PCI now includes other new techniques
capable of relieving coronary narrowing. Accordingly,
in this document, rotational atherectomy, directional
atherectomy, extraction atherectomy, laser angioplasty,
implantation of intracoronary stents and other catheter
devices for treating coronary atherosclerosis are considered
components of PCI. In this context PTCA will be used
to refer to those studies using primarily balloon angioplasty
while PCI will refer to the broader group of percutaneous
techniques. These new technologies have impacted the
effectiveness and safety profile initially established
for balloon angioplasty. Moreover, important advances
have occurred in the use of adjunctive medical therapies
such as glycoprotein (GP) IIb/IIIa receptor blockers.
In addition, since publication of the previous Guidelines
in 1993, greater experience in the performance of PCI
in patients with acute coronary syndromes and in community
hospital settings has been gained. In view of these
developments, further review and revision of the guidelines
is warranted. This document reflects the opinion of
the third ACC/AHA committee charged with revising the
guidelines for PTCA to include the broader group of
technologies now termed PCI.
Several issues relevant to the Committee's process
and the interpretation of the Guidelines have been noted
previously and are worthy of restatement. First, PCI
is a technique that has been continually refined and
modified; hence continued, periodic Guideline revision
is anticipated. Second, these Guidelines are to be viewed
as broad recommendations to aid in the appropriate application
of PCI. Under unique circumstances, exceptions may exist.
These Guidelines are intended to complement, not replace,
sound medical judgment and knowledge. They are intended
for operators who possess the cognitive and technical
skills for performing PCI and assume that facilities
and resources required to properly perform PCI are available.
As in the past, the indications are categorized as Class
I, II, or III, based on a multifactorial assessment
of risk as well as expected efficacy viewed in the context
of current knowledge and the relative strength of this
knowledge. Initially, this document describes the background
information that forms the foundation for specific indications.
Topics fundamental to coronary intervention are reviewed
followed by separate discussions relating to unique
technical and operational issues. Formal recommendations
for the use of angioplasty are included in Section
V. Indications are organized according to clinical
presentation. This format is designed to enhance the
usefulness of this document for the assessment and care
of patients with coronary artery disease (CAD).
This document employs the ACC/AHA style classification
as Class I, II, or III. These classes summarize the
indications for PCI as follows:
Class I: Conditions for which there is evidence
for and/or general agreement that the procedure or treatment
is useful and effective.
Class II: Conditions for which there is conflicting
evidence and/or a divergence of opinion about the usefulness/efficacy
of a procedure or treatment.
Class IIa: Weight of evidence/opinion is in favor
of usefulness/efficacy.
Class IIb: Usefulness/efficacy is less well established
by evidence/opinion.
Class III: Conditions for which there is evidence
and/or general agreement that the procedure/treatment
is not useful/effective, and in some cases may be harmful.
The weight of evidence in support of the recommendation
for each listed indication is presented as follows:
Level of Evidence A: Data derived
from multiple randomized clinical trials.
Level of Evidence B: Data derived from a
single randomized trial or nonrandomized studies.
Level of Evidence C: Consensus opinion of
experts.
