RevascularizationCoronary Artery Bypass Graft and

Percutaneous Transluminal Coronary Angioplasty

Coronary Artery Disease

Coronary Artery Disease (CAD) the reason for revascularization.

CAD: Narrowing of the coronary arteries, usually caused by atherosclerosis.

Atherosclerosis: the most common type of arteriosclerosis, characterized by cholesterol-lipid-calcium deposits on the walls of arteries.

Arteriosclerosis: Thickening and hardening of the arteries.

Taber’s Medical Dictionary 2005

Definitions

Epidemiology

Prevalence (2010): 6% of Americans (18,775,860) have CAD.

A problem the size of a small continent!

Wikipedia, “World Populations” Population of Australia 22 Billion

Treatment CABG

Treatment CABG

Treatment PTCA

Treatment PTCA

Epidemiology and Co$T

CABG PTCA

Annual Procedures (Incidence) +500,000 +1.4 million

Cost per case $60,853 $17,763-28,558

Total Cost of Cardiovascular Disease$393 billion annually!

In 2008 the United States spent nearly 400 billion dollars to bailout the housing industry, avoiding a suspected world wide financial crisis. Many citizens were outraged at the exorbitant amount spent.

Clinical Aspects

Symptoms: Dyspnea, palpitations, vertigo, angina, sub-sternal pain, GI distress, nausea, indigestion, diaphoresis, impending doom, malaise, fatigue, pain that is exacerbated with activity or radiates to arm, neck or jaw.

Clinical Aspects

Symptoms: Dyspnea, palpitations, vertigo, angina, sub-sternal pain, GI distress, nausea, indigestion, diaphoresis, impending doom, malaise, fatigue, pain that is exacerbated with activity or radiates to arm, neck or jaw.

Laboratory

Common Lab Test: CK, CK-MB, Troponin, C-Reactive Protein (CRP), hs CRP, Lipid Profile, Fibrinogen, BNP.

The cost of these labs range from $39-$79 individually. You can also get a great package deal for only $299.00 according to Heath Testing Centers of America. Some hospitalized patients receive these tests every 8 hours. According to CNBC the average monthly cost of a gym membership is $40-50.00.

Diagnostic Testing

Test Brief Explanation

Exercise ECG testing Patients are exercised at near 85% VO2 max . Patient is monitored for ECG changes.

Planar Thallium A Radiotracer is injected into blood stream. Photos are taken with a gamma camera before and after exercise.

Stress Echocardiography Heart structural and functional capacities are measured under stress of exercise by ultrasound.

PET/CT and SPECT The use of radioisotope and specialized CT or Photon machines to create 3D images of organs.

Complications

• Ventricular Arrhythmia, Stroke, Renal Failure, Bleeding, Ventricular Rupture, Respiratory Failure, Pulmonary Embolism, Dissection and Abrupt Closure of Arteries, Coronary Artery Intramural Hematoma, Perforation, Distal Embolization, Side Branch Occlusion, Stent Jail, Failure Of Stent Deployment, Stent Thrombosis, Stent Infection, Myocardial Ischemia, Infection, Access Site Bleeding, Retroperitoneal Bleeding, Anticoagulation-associated Bleeding, Drop In Platelet Count, Peripheral Artery Disease, Radiation Exposure, Myocardial Infarction, Death.

“PREHAB”ilitaion

• A recent study preformed in 2010 indicates advantages of exercise before PTCA and CABG.

“The incidence of artery spasm, occlusion and damage is lower in larger arteries with preserved endothelial function. We conclude that the beneficial effects of exercise training on both artery size and function, which are particularly evident in individuals who possess cardiovascular diseases or risk factors, infer that exercise training may reduce complication rates following catheterization and enhance the success of arteries harvested as bypass grafts.”

Sports Medicine, Volume 40, Number 6, 1 June 2010 , pp. 481-492(12)

Effects of CABG and PTCA on ability to exercise

CABG PTCATypically hemodynamicly unstable for first 24 hours post op.

Patients must remain bedfast for several hours after procedure.

Reduced Upper Extremity functional capacity for 3-4 weeks post op.

If uncomplicated, patients regain or improve exercise ability quickly.

Lower extremity sluggishness, edema and weight gain. Chest tubes and drains may cause a tripping hazard. Decreased pulmonary function can inhibit function as well.

Patients must monitor for hematoma or bleeding in groin. No strenuous resistance exercise for 2-3 weeks.

May have decreased, Hgb/HCT, energy reserves. General fatigue and malaise.

Effects of Medications

Medication HR (R, E) BP ECG Exercise Capacity

Asprin No Effect No Effect No Effect No Effect

Plavix No Effect No Effect No Effect No Effect

GP2B/3A inhibitors No Effect No Effect No Effect No Effect

Beta Blockers Decrease R,E Decrease Decrease Increases with anginal patients,

D without

ACE Inhibitors Neutral Decrease Neutral Neutral, except w/ CHF then Increase.

Statins No effect No effect No effect Known to cause muscle soreness

ARB’s Neutral Decrease Decrease Neutral

Antiarrhythmics Class dependent Mostly Neutral Class Dependent Neutral

Nitrates Increase R,E Decrease Increase Increase

Calcium Chanel Blockers

Increase R,E Decrease Decreases Ischemia Increases with anginal patients.

R=Resting E= Exercise, BP=Blood Pressure,

Effects on Exercise Bout

CABG and PTCA

• Increased blood flow beyond prior occlusion, reduces ischemia related to exertion.

• Decreases in angina and associated increased work capacity.

• Improved myocardial oxygen supply may improve ventricular contractility and wall motion, thus increasing stroke volume.

• Favorable hemodynamic response to exercise.

• Improved chronotropic impairment (delay in HR recovery).

• Diminished or elimination of ischemia related ventricular arrhythmias.

Effects on Exercise Training Chronic

• Average improvement of 20% increase in max VO2max

• Reduced heart rate and blood pressure = decrease in myocardial workload and oxygen demand.

• Improved autonomic control

• Better glucose metabolism

• Each MET increase in exercise capacity, decreases mortality by 8-17%

Exercise Testing

Methods Measures Endpoints Comments

Cycle (Ramp 17W/min, 25-50 W/3 min stage)

12 EKG, HR Dysrythmias

>2mm ST change

Ischemic Threshold

ST changes can occur with restenosis .

Treadmill (1-2 METS/ 3 min stage)

Bruce or Naughton

Protocol.

RPE(6-20), Gas analysis (VO2max/peak), BP, RPP

T wave inversion

SBP > 250 mmhg or DBP >115 mmHg

Decrease in SBP 10 mmHg

Angina score of 3-4.

Chronotropic impairment suggests poor prognosis

Isokenetic or Isotonic 90% MVC

Greatest load lifted 2-3 times

3 consecutive reps Do not preform until sternum is healed. Up to 12 weeks.

WARNING: It is not recommended to exercise test CABG patients for 3-5 weeks post procedure due to, in part, sternal instability and little clinical benefit. PTCA: Patients can be tested sooner and more often; 1-2 weeks after procedure.

Remember Exercise Testing is not normal exercise or activity!!!

To be used for prognosis, program establishment, and functional improvement.

Exercise Prescription

Mode Goals Intensity/Frequency/ Duration

Time to Goal

Aerobic

Large Muscle Activities

Leg/Arm ergometery

Increaes Aerobic Capacity

Decreaes HR and BP response to submaximal exercise

Decrease CAD, Increase ADLs

RPE 11-16

(begin 11-13)

40-80 VO2max or HR reserve

4-7 days a week

20-60 min sessions

4-6 Months

Resistance

Circuit Training

Increase ability to preform ADLs and occupational work

Increase Muscle Strength

Decrease RPP (Rate Pressure Product) while lifting

40-50% MVC (avoid vasalva)

2-3 days a week

8-10 different exercises

Resistance increase overtime

12 weeks Post CABG

4-6 months

Flexibility

Upper/Lower

ROM

Decrease Injury

Maintain ROM

2-3 days per week

Static Stretches hold for 10-30 sec

4-6 months

Exercise PrescriptionImportant points to remember

• Know the signs of when to stop (Angina, SOB, Vertigo, change in Vital Signs).

• Walking is one the best exercises for most patients (40-50 HRR), and it’s a indicator of prognosis.

• Encourage ROM and ambulation quickly in CABG.

• Resistance training should always be proceeded by aerobic training.

Summary and Conclusion

There are millions of patients receiving revascularization procedures in the United States each year. There is a need for exercise professionals to understand and apply the principles of FITT individually for these patients. The proper use of exercise in Cardiac Rehab prevents restenosis, decreases post procedure cardiac complications, increase quality of life, and save millions of dollars each year.

References

Taber’s Medical Dictionary 2005

“Antithrombotic therapy for intracoronary stent implantation: General use”: Donald Cutlip, MDThomas Levin, MD: Up to Date..

Arterial Prehabilitation: Can Exercise Induce Changes in Artery Size and Function that Decrease Complications of Catheterization? : Sports Medicine, Volume 40, Number 6, 1 June 2010 , pp. 481-492(12)

“Periprocedural complications of percutaneous coronary intervention “, Authors Joseph P Carrozza, MD, Donald Cutlip, MD, Thomas Levin, MD, David O Williams, MD