Page 562 - Cardiac Nursing

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538 PA R T I V / Pathophysiology and Management of Heart Disease
Women based solely on chronologic age but should be patient centered
Women presenting with CHD frequently have increased severity with consideration of the patient’s general health, functional and
of disease at time of presentation. Women are generally older cognitive status, comorbidities, life expectancy, and preference
when they present with their first coronary event, and often have and goals. Clinical trials have shown benefits from early invasive
have diffuse atherosclerotic disease and a higher incidence of co- procedures with similar success rates as younger patients but with
morbidities, including hypertension, diabetes mellitus, hypercho- higher risks of bleeding and vascular complications. Older adults
lesterolemia, peripheral vascular disease, and unstable angina. often have altered pharmacokinetics, risk of drug interactions, and
Women have an excellent long-term prognosis after a successful polypharmacy contributing to complications. 14 Increased risk of
procedure even though coronary vessel lumen may be smaller. Al- neurological events secondary to diffuse atherosclerotic disease has
though newer revascularization procedures with stents and con- also been seen in older adults.
comitant use of glycoprotein (GP) IIb/IIIa receptor inhibitors
have shown similar benefit in women as men, these interventions
have not eliminated the gender difference in mortality that has PERCUTANEOUS
persistently shown higher rates with device treatment in the set- TRANSLUMINAL CORONARY
ting of ACS and elective procedures in women. 3,6
ANGIOPLASTY
Patients With Diabetes Mellitus
Patients with diabetes mellitus account for about 20% of revascu- Dotter and Judkins first proposed the concept of transluminal an-
15
larization procedures. PCI in patients with diabetes is associated gioplasty in 1964. Gruentzig initially applied the technique of
with less favorable long-term outcomes, need for repeat interven- percutaneous transluminal coronary angioplasty (PTCA) to hu-
1
tion because of restenosis, multivessel disease, and possible pro- man coronary arteries in 1977. Since the first PTCA, advances in
gression of underlying disease. Current guidelines have favored catheter and balloon techniques have improved immediate and
CABG surgery for patients with diabetes who have two-or-three long-term success. Although conventional balloon angioplasty is a
vessel disease because of more complete revascularization and de- core procedure in the catheterization laboratory, it is usually not a
creased need for repeat intervention. 7–9 Use of DES has improved stand-alone procedure but is now augmented by adjunctive stent-
the long-term outcomes in patients with diabetes who have single- ing, which greatly improves procedural success and reduces com-
vessel disease. 10 An intravenous GP IIb/IIIa receptor inhibitor plication rates.
should be administered for diabetic patients with unstable angina The desired therapeutic effect of balloon angioplasty is the en-
or NSTEMI; GP IIb/IIIa receptor inhibitors appear to improve largement of the internal luminal diameter of the diseased artery.
the outcome of PCI with reduced death, MI and repeat revascu- Application of balloon pressure to an atherosclerotic lesion results in
larization. 11 plaque rupture, disruption of the endothelium, and stretching of
the vessel segment, which enlarges the vessel lumen size (Fig. 23-1).
Patients With Multivessel CAD Guiding catheters are used to cannulate the coronary artery and
The two primary interventions for multivessel CAD are PCI and to provide support for delivery of guidewires and interventional
CABG. Several randomized and observation studies have com- devices. In the catheterization laboratory, after the guide catheter is
pared the long-term outcomes of these two interventions before placed and the wire crosses the lesion, a balloon catheter is selected
the introduction of DES. These trials demonstrated that in ap- that most closely approximates the diameter of the nondiseased ref-
propriately selected patients with multivessel coronary disease, an erence segment adjacent to the site to be treated. The prepared and
initial strategy of standard PCI with bare metal stent (BMS) yields flushed balloon is loaded onto the free end of the guidewire. The
similar overall outcomes to initial revascularization with CABG. balloon is passed into the guide catheter, down the proximal vessel,
An important exception is in the subgroup of patients with dia- and across the lesion. Once the balloon catheter is positioned
betes mellitus who had reduced cardiac mortality with CABG across the lesion, the balloon is inflated using a handheld inflation
compared to PCI. Patient preference, patient compliance with device equipped with a pressure dial. Multiple balloon inflations of
dual antiplatelet therapy, surgical risk, angiographic characteris- variable pressure and duration are used depending on the type of
tics, LV function, and co-morbid issues need to be considered be- lesion and the physician preference. The response of the lesion to
fore a treatment strategy is selected. 12 dilatation is assessed by contrast injection and repeat angiography
An observational study from the New York State Registry iden- through the guiding catheter with the guidewire in place. When
tified patients with multivessel disease who received DES or under- the lesion in successfully dilated, the balloon apparatus is removed
went CABG. Conclusions from the registry indicated lower mor- and multiple angiographic projections are reviewed. The guidewire
tality rates and repeat revascularization with CABG compared to and guiding catheter are removed after an adequate result is
13
DES. Currently, ongoing multicenter, randomized, controlled tri- obtained.
als such as SYNTAX (Synergy between PCI with Taxus and Cardiac
Surgery) and FREEDOM (Future Revascularization Evaluation in Cutting Balloon Angioplasty
Patients With Diabetes Mellitus—Optimal Management of Multi-
vessel Disease), are evaluating multivessel DES versus bypass sur- Cutting balloon angioplasty uses a balloon designed with three-to-
gery in different subsets of patients and will provide guidance for se- four microscopic blades or atherotomes mounted on the balloon
lection of treatment that will benefit specific groups of patients. 12 surface that protrude slightly above the balloon surface when in-
flated (Fig. 23-2). The mechanism of action referred to as athero-
Older Adults tomy utilizes the balloon device to make three-to-four controlled
Patients aged 75 years and older should be considered for PCI in incisions that score the plaque in an atherosclerotic coronary artery.
a similar manner as younger patients. Decisions should not be The noncompliant balloon then dilates the incised areas resulting