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CARDIAC SYSTEM

49

Table 1-18. American Ilearr Association's Functional Capacity and Objective Assessment of Patients with Diseases or the Heart Functional Clpacitt

Objective Assessmentb

Class I: Patiems with cardiac disease but without

No objective evidence of

resulting limitations of physical activity. Ordicardiovascular disease

nary physical activity does nOt cause undue

fatigue, palpitation, dyspnea, or anginal pain.

Class II: Patients with cardiac disease thar results

Objective evidence of

m a slight limitation of physical activity.

minimal cardiovascular

Paricnr� are comforrable at rest, but ordinary

disease

physical activity results in fatigue, palpitations, dyspnea, or anginal pam.

Class III: Patients with cardiac disease that

Objective evidence of

results 111 a marked limitation of physical

moderately severe caractivity. I>atienrs arc comforrable at rest, but

diovascular disease

less-than-ordinary activity causes fatigue, palpitations, dyspnea, or angmal pam.

Class IV: Patlenrs with cardiac disease [hat

Objective evidence of

results in an inability to carry on any physical

severe cardiovascular

activit), Without discomfort. Fatigue, palpitadisease

tions, dyspnea, or .,mglllal palll may be presenr

even at rest. If any physical activiry is undertaken, symptoms increase.

�F""cliu".,l cap,JClty refers to subjective symptoms of the paflenr. This aspect of the

classification is idenncal lo the New York Heart Association's Classification.

"Ob;ectwe ,lssessmem was added to the claSSification system by the American 'Ieart

Assouauon In 1994. II refers 10 measurements such as electrocardiograms, stress tests,

ech()(ardiogram�. and radiologic Images."l

Functional Classification of Heart Disease, and this new classification is

described in Table 1 - 1 8. Activity progression for patients hospitalized

with CHF is based on the ability of medical treatments (e.g., dillresis, inotropes) to keep the patient Out of heart failure. When a patient with CHF

is medically stabilized, the CHF is thought to be "compensated." Clinical

examination findings allow the therapist to continuously evaluate the

patient'S tolerance to the activity progression. Although metabolic equivalent (MET) tables are nOt commonly used clinically, they do provide a method of progressively increasing a patient'S activity level. As greater

MET levels are achieved with an appropriate hemodynamic response, the

next level of activity can be attempted. Table 1 - 1 2 provides MET levels

for common activities that can be performed with patients.

50

AClITE CARE HANDBOOK FOR PHYSICAL THERAPISTS

Management

The following section discusses surgical and nonsurgical procedures,

pharmacologic interventions, and physical therapy interventions for

patients with cardiac dysfunction.

Revascu/arization and Reperfusion of the Myocardium

Thrombolytic Therapy

Thrombolyric therapy has been established as an acute management

strategy for patients experiencing an M1 because of the high prevalence

of coronary artery thrombosis during acute Mis. Thrombolytic agents,

characterized as fibrin-selective and nonselective agents, are administered

to appropriate candidates via intravenous access. The most common

agents include: streptokinase (nonselective), anisylated plasminogen

streptokinase activator complex (nonselective), and tissue plasminogen

activator (t-PA) (fibrin-selective)." Fibrin-selective agents have a high

velocity of clot lysis, whereas the nonselective agents have a slower clot

lysis and more prolonged systemic lyric state.

The indication for thrombolytic therapy includes chest pain that is

suggestive of myocardial ischemia and is associated with acute ST segment elevation on a 1 2-lead ECG or a presumed new left ventricular bundle branch block. Hospital protocol regarding the time period to perform thrombolyric therapy usually varies, as clinical trials have led to some controversy.12 Some studies show benefits only if treaanent is conducted within 6 hours of symptoms, whereas others have demonstrated improvement with treatment up to 24 hours after onset of symptoms. 12

The contra indications to thrombolytic therapy generally include

patients who are at risk for excessive bleeding. Because of the variability that can occur among patients, many contraindications ate considered relative caurions, and the potential benefits of therapy are

weighed against the potential risks. Thtombolytic therapy is used in

conjunction with other medical treatments such as aspirin, intravenous heparin, intravenous nitroglycerin, lidocaine, atropine, and a beta-blocker. As previously discussed, early peaking of CK-MB is

associated with reperfusion.'2

Percutaneous Revascularization Procedures

Percutaneous revascularization procedures are used to return blood

flow through coronary arteries that have become occlusive secondary

CARDIAC SYSTEM

5 1

to atherosclerotic plaques. The following list briefly describes three

percutaneous revascularization proceduresl2:

1 . PerClltalleOllS translumillal corollary allgioplasty (PTCA)

is performed on small atherosclerotic lesions that do not completely occlude the vessel. PTCA can be performed at the time of an initial diagnostic catheterization, electively at some time after a

catheterization, or urgently in the setting of an acute Ml.

A sheath is inserted into the femoral, radial, or brachial artery,

and a catheter is guided through the sheath into the coronary

artery. A balloon system is then passed through the catheter to the

lesion site. Inflations of variable pressure and duration may be

arrempted to reduce the lesion by at least 20% diameter with a

residual narrowing of less than 50% in the vessel lumen 12 Owing

to some mild ischemia that can occur during the procedure,

patients occasionally require temporary transvenous pacing, intraaortic ballon counterpulsation, or femorofemoral cardiopulmonary bypass circulatory suppOrt during PTCA.

The use of coronary laser angioplasty, directional coronary

atherectomy, and endoluminal stents was developed in response to

the major limitations of PTCA, which include abrupt closure (in

up to 7.3% of patients), restenosis, anatomically unsuitable

lesions, chronic total occlusions, unsatisfactory results in patients

with prior coronary arrery bypass graft (CABG) surgery '·

2.

Coronary laser angioplasty uses laser energy to create precise