Practice Pattern D represents a progression in heart disease beginning with cardiac pump dysfunction, which eventually may progress to cardiac pump failure. It is critically important that a physical therapist be able to distinguish between a person with cardiac pump dysfunction and a person with cardiac pump failure. The inclusion/exclusion criteria of Practice Pattern D list two specific pathologies that may distinguish between cardiac pump dysfunction from cardiac pump failure (ejection fraction <30% and exercise-induced myocardial ischemia) and two specific impairments that may distinguish between cardiac pump dysfunction from cardiac pump failure (hypoadaptive blood pressure response to exercise and achieved MET level during exercise testing).1 These distinguishing characteristics are listed in Box 18-1.
BOX 18-1 Patients/Clients Diagnostic Group Characteristics for Practice Pattern D
Practice Pattern D: Impaired Aerobic Capacity and Endurance Associated With Cardiovascular Pump Dysfunction/Failure Patients/clients who have impaired aerobic capacity associated with cardiovascular pump dysfunction and who may have one or a combination of the following:
Abnormal heart rate response to increased oxygen demand
Decreased ejection fraction (30%–50%)
Exercise-induced myocardial ischemia (1–2 mm ST-segment depression)
Functional capacity of less than or equal to 5–6 METS
Hypertensive blood pressure response to increased oxygen demand
Nonmalignant arrhythmias
Symptomatic response to increased oxygen demand
Angioplasty or atherectomy
Cardiomyopathy
Coronary artery bypass grafting
Coronary artery disease
Hypertensive heart disease
Uncomplicated myocardial infarction
Valvular heart disease
Excludes patients/clients with:
Age <4 months
Airway clearance impairment
Mechanical ventilation
Heart failure
Practice Pattern D: Impaired Aerobic Capacity and Endurance Associated With Cardiovascular Pump Dysfunction/Failure Patients/clients who have impaired aerobic capacity associated with cardiovascular pump failure and who may have one or a combination of the following:
Abnormal heart rate response to increased oxygen demand
Ejection fraction of less than 30%
Severe exercise-induced myocardial ischemia (> 2 mm ST-segment depression)
Functional capacity of less than or equal to 4–5 METs
Flat or falling blood pressure response to increased oxygen demand
Complex ventricular arrhythmias
Symptomatic response to increased oxygen demand
Atrioventricular block
Cardiogenic shock
Cardiomyopathy
Complicated myocardial infarction
Age <4 months
Mechanical ventilation
Membrane oxygenator
Intra-aortic balloon pump
Ventricular assist device
Modified with permission from American Physical Therapy Association. Guide to Physical Therapist Practice. 2nd ed. Phys Ther. 2001 Jan;81(1):9-746.
Although these tests and measures are available from the patient’s medical history, they may, in fact, be history and not represent current cardiac performance. Similarly, the only aforementioned test providing specific information to distinguish cardiac pump dysfunction from failure is the ejection fraction. Another simple measurement that can be performed by a physical therapist that may provide important information to distinguish cardiac pump dysfunction from failure is observing the blood pressure response during a controlled expiratory maneuver.2-10 This simple test can provide important information about the disablement of heart disease and can provide a basis upon which the physical therapist can determine necessary outcomes, subsequent examinations, and specific treatment methods. The most relevant characteristics of cardiac pump dysfunction and cardiac pump failure will be presented in the following sections beginning with the microanatomy and physiology of both the dysfunctional and the failing cardiac pump, which will be followed by a brief review of the effects of ...