3.2 Risk Stratification Flashcards
Risk stratification is based on what idea?
Is this idea always true?
A patient’s history and profile can suggest who should be watched closely for complications (ex. cardiac arrest)
should be taken with a grain of salt, because cardiac events can occur without normal symptoms, and from plaque build-ups <70%
What do we want to consider when determining if the patient needs supervision?
Absolute risk
disease progression
concurrent disease conditions
age
possible complications that can occur during exercise
What factors are believed to increase risk of adverse cardiac events during physical exertion?
- high intensity exercise
- known CVD
- high probability of CVD
- ppl with many risk factors, especially if uncontrolled
- beginning an exercise program
- showing up to exercise UNWELL
How often will you see some type of problem during exercise for cardiac rehab patient?
every 320 hrs of exercise
In risk stratification, what factors do we want to consider?
Left ventricular ejection fraction
Ischemic load
Exercise tolerance
Ventricular Dysrhythmia
Control of risk factors affecting disease progression
Age
Co-morbidities
What are the 2 “shockable” arrhythmia?
VTAC or VFIB
What are the signs and symptoms to be aware of in risk stratification?
discomfort
short of breath
fatigue
orthopnea (short of breath laying down)
dizziness or syncope
ankle edema - pitting edema
palpitations
other target organ damage, claudication, etc.
What is orthopnea?
shortness of breath while laying down
What is syncope and pre-syncope?
syncope: fainting
pre-syncope: light-headedness or faint
What is the AHA risk stratification criteria for Class A 1,2,3?
A-1: child, adolescent, men<45, women<55 who have no symptoms or known CVD or coronary risk factors
A-2: men≥45yrs, women≥55yrs; no symptoms or known CVD, <2 major CV risk factors
A-3: men≥45yrs, women ≥55yrs, no symptoms or known CVD, ≥3 major CV risk factors
What is the AHA risk stratification criteria for Class B?
known, stable CVD with low risk for complications with vigorous exercise, but slightly greater than apparently health individuals
AHA Class B includes individuals with what diagnoses?
- CAD (MI, CABGS, PTCA) - but stable conditions
- Valvular heart disease (excluding severe valvular stenosis or regurgitation)
- Congenital heart disease
- Cardiomyopathy
- Exercise test abnormalities that don’t meet class C criteria
-medically stable
-NO unstable angina
What is the exercise capacity of a class B individual?
≥ 6 METS
What are the symptoms of a AHA class B individual?
no symptoms, or no symptoms below exercise at 6 METS
What is the AHA risk stratification criteria for Class C?
individuals with moderate to high risk for cardiac complications during exercise and/or unable to self-regulate activity or understand recommended activity level
AHA Class C includes individuals with what diagnoses?
- CAD (MI, CABGS, PTCA) - but stable conditions
- Valvular heart disease (excluding severe valvular stenosis or regurgitation)
- Congenital heart disease
- Cardiomyopathy, EF ≤30%
- Complex ventricular arrhythmias not well controlled
What are the clinical characteristics of a class C individual?
- Exercise capacity <6 METS
- Angina or ischemia ST depression at workload <6 METS
- Fall in systemic BP below resting level with exercise
- Nonsustained ventricular tachycardia with exercise
- previous cardiac arrest that was not in presence of acute MI or during clinical procedure
- physician believes they have a possibly life threatening med problem
What is the difference between class B and class C in terms of supervision?
B - medical supervision suggested for initial prescription session; then supervision by trained nonmedical personnel until able to monitor activity
C - medical supervision during all exercise sessions until safety is established
What individuals are classified in AHA Class D?
- unstable ischemia
- severe and symptomatic valvular stenosis or regurgitation
- congenital heart disease
- heart failure that’s not compensated
- uncontrolled arrhythmias
- other medical conditions that can be aggravated by exercise
What are the activity guidelines for Class D?
no activity
daily activities must be prescribed on the basis of the individual assessment by the patient’s physician
What is the risk rate compared to functional capacity (METS)?
low risk: >8 METS
intermediate risk: 5-8 METS
high risk: <5 METS
If not able to achieve _ METS, the risk of premature death is a lot higher.
However, you maximize benefit (plateau) at about __ METS.
<7 METS - risk of premature death is a lot higher
Maximize benefit at about 10 METS
A brisk walk would be considered about _ METS.
3 METS
Myocardial ischemia is caused by what?
decreased supply (primary ischemia)
increased demand (secondary ischemia)
or a combination (mixed ischemia)
What is ischemic burden?
the sum of all episodes of myocardial ischemia (with or without angina) = ichemic burden
What aspects of dysrhythmias predict health outcomes?
> 10 PVC’s per min
Non-sustained VT
Sustained VT
What is a PVC?
premature ventricular contraction
Is prolonged strenuous exercise a good thing (ie., marathons or ultra runs)?
Can have damage on the heart
ex. study with rats and long-term intensive exercise training = increased myocardial inflammation, fibrosis, reduced arrhythmia threshold
Extreme endurance exercise is associated with the release of what?
It may be associated with what diagnoses?
Release of troponin, CPK-MB, and BNP (increase in cardiac enzymes, damaging heart muscle)
Transient cardiac dysfunction
Cardiac fibrosis
Dysrhythmias
can generate scar tissue in the heart
- may see calcification in coronary arteries after long-term
What are the signs and symptoms below which an upper limit for exercise intensity should be set?
onset of angina pectoris (chest pain)
decreased SBP, SBP > 240mmHg
DBP >110mmHg
≥ 1mm ST-segment depression
Evidence of left ventricular dysfunction
Threatening ventricular arrhythmias
Peak exercise HR should be at least __beat/min below the HR associated with these signs and symptoms of upper limit.
10 beats/min
For an individual that suffers an out-of-hospital sudden cardiac arrest, the likelihood that they will survive through hospital discharge is __%.
6%
With every additional minute of cardiac arrest, what happens to the likelihood of survival?
survival drops 10%
In the population that routinely exercise, the risk of MI or SCD increases by how much when participating in vigorous aerobic exercise?
risk of MI increases 2-5x
What are the guidelines for progression to independent exercise with minimal or no supervision?
-Functional capacity ≥ 8 METS
-appropriate hemodynamic response to exercise and recovery
-appropriate ECG response at peak exercise
-cardiac symptoms are stable or absent
-stable and/or controlled baseline HR and BP
-adequate management of risk factors
- knowledge and understanding of safe exercise prescription
-knowledge of disease process, signs and symptoms, medication use and side effects
-compliance and success with program of risk intervention
