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These recommendations are made at the request of cardiologists,
medical insurance funders and suppliers of drug-eluting stents
on the eve of the commercial release of the first of these
devices. These recommendations are based upon the limited
information presently available from published articles and
preliminary oral presentation of results. Presently, the recommendations
cannot be extended beyond the indications that have been employed
in the various trials. Furthermore, in recognition of the
very high cost of these devices, the recommendations support
the use of drug-eluting stents only in circumstances in which
a significant clinical benefit for the patient can be anticipated.
These recommendations will be updated and expanded from time
to time as new information becomes available.
Trials of the rapamycin / sirolimus-eluting stent have been
conducted in limited numbers of patients. Entry to the trials
allowed stable and unstable patients to be studied, though
patients with intracoronary thrombus and/or very recent myocardial
infarction were excluded. The stents were implanted only in
de novo single native vessel stenosis, in symptomatic patients
or in a stenosis shown to be functionally significant by pressure
or flow wire. The stenotic lesions had to be less than 15
mm in length, Type A/B1/B2, in vessels between 2.5 and 3.5
mm in diameter. The trials excluded patients with an ejection
fraction less than 30%, total occlusions, main stem lesions,
ostial lesions, lesions with large side branches of more than
2 mm diameter and calcified lesions that could not be predilated.
Patients received a thienopyridine (clopidogrel or ticlopidine)
for 2 months after the implantation. Follow-up has been reported
for up to one year.
The initial sirolimus trials universally reported a zero
restenosis rate for the first year. Preliminary results of
sirolimus stent placement in less than ideal lesions are reported
have a 2% restenosis rate at 8 months. Provisional results
of paclitaxel-eluting stents also indicate a low restenosis
rate, though higher than those encountered with sirolimus-eluting
stents.
One preliminary report of a small number of patients who
received sirolimus-eluting stents indicates a similar of benefit
in diffuse in-stent restenosis.
The following lesions are more prone to restenosis:
1. Small vessels < 3 mm diameter
2. Lesions > 25 mm in length
3. Highly proximal left anterior descending lesions proximal
to the first septal perforator and first diagonal branch
The following patient group is more prone to restenosis:
1. Diabetics
The consequences of restenosis are potentially more serious
in the following circumstance:
1. Lesions that supply a large area of viable
myocardium.
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1. It is considered appropriate to use a drug-eluting stent
in a coronary artery particularly in combinations of the following
circumstances:
a proximal stenosis in a vessel 3 mm or less in diameter,
a proximal stenosis > 15 mm in length,
a highly proximal left anterior descending stenosis,
a stenosis in a vessel supplying a large area of myocardium
a stenosis in a diabetic.
2. A drug-eluting stent may be appropriate for treatment
of a diffuse in-stent restenosis.
1. It is inappropriate to use more than one drug-eluting
stent per vessel
2. It is inappropriate to use drug-eluting stents in more
than two coronary arteries.
3. It is considered inappropriate to use a drug-eluting stent:
the left main coronary artery,
in patients with proximal triple vessel disease and
in proximal double vessel disease that includes the LAD
The outcome in these patients is better with aorto-coronary
bypass grafting than with percutaneous intervention (Duke
database).
4. It is considered inappropriate to use a drug-eluting stent
in patients with
a stenosis <15 mm in length in a vessel >3.5 mm
in diameter
any stenosis in a vessel > 4 mm in diameter
distal disease
disease within a branch of one of the major coronary arteries
a bifurcation lesion in which the branch is >2mm in diameter
a focal in-stent restenosis
a saphenous vein graft stenosis
5. It is inappropriate to use a drug-eluting stent after
using a debulking device within the same vessel.
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Cardiologists
The Cardiologist must be aware of the high cost of these
devices and the impact of their use on the patient's financial
and medical insurance resources. In some instances the use
of these devices will deplete the patient's prosthesis allocation
by his/her medical insurer and the excess then may have to
be borne as a personal expense by the patient. The absolute
benefit to the patient should be enhanced and the global impact
upon costs should be diminished by meticulous application
of the above recommendations. When a cardiologist chooses
to exceed the limits of these recommendations, he/she may
be required to justify his/her action to the concerned funder/patient,
without the support of the SA Heart Association.
All cardiologists implanting these devices should participate
in contributing information to the company database referred
to below.
Distributors
It is strongly recommended that each company distributing
a drug-eluting stent establish a comprehensive, global registry
on the use of their particular device that includes the indications
for the procedure and the short- and long-term outcomes. The
information should be captured in a database. The data from
these registries should be made available to the South African
Heart Association at 6 monthly intervals.
Medical insurers
Medical insurers should recognise the advantages of drug-eluting
stents. Although upfront costs will be higher, the long-term
benefit will be a reduced need for anti-anginal therapy and
re-intervention either by repeat percutaneous technique or
aorto-coronary bypass grafting, leading to a certain reduction
in cost.
Medical insurers may request the South African Heart Association
to conduct a peer-review of any practitioner whose utilisation
of drug-eluting stents is suspected to exceed these recommendations.
The costs of such review will be borne by the insurer concerned.
Prof AF Doubell (President)
Dr C Schamroth (Vice-President & Chairman Private Practice
Committee)
Dr AJ Dalby (Chairman, Ethics & Guidelines Committee)
Prof P Manga (Chairman, Full-time Practice Committee)
Dr GA Cassel
Dr R Girdwood
Dr TA Mabin
Dr R Matisonn
Dr S Spilkin
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