Cardio - Unit 2, Medical Management and Potential Complications of ACS Flashcards
Medical Management of ACS
- Beta blocking drugs
- Organic nitrates (sublingual nitroglycerin)
- Oxygen reduces dyspnea
- Morphine relieves pain and dyspnea
- IV fluids if potential for BP to crash
What do beta-blocking drugs do to the heart?
Reduce the work of the heart by blocking adrenaline effects, blood vessel dilation
What do organic nitrates (sublingual nitroglycerin) do to the heart?
- Reduce preload, thereby work, potential for excessive preload reduction - venous dilation and decreases after load by arterial dilation
- Small effect on coronary blood flow
Sequencing of Drugs related to Thrombosis and Coagulation
- Thrombolytic during ACS to restore blood flow
- Heparin to reduce coagulation rapidly
- Maintenance anticoagulation with warfarin
- Asprin or plavix as an antithrombotic
- Cholesterol-lowering drugs
What happens if there’s late administration of thrombolytics?
Can cause reprofusion injury
What do thrombolytics do?
Activate the natural anti clotting system which breaks down fibrin threads and dissolves any formed clot
Clinical Implications of Anti-thrombotic
- Risk of bleeding and bruising are increased
- Internal hemorrhage risk
- Avoid bumping
Clinical implications of cardiac meds
- Acute - be sure pt has drug available
- Chronic - ensure pt is taking it
- Cause DECREASED cardiac response to exercise
- INCREASE exercise tolerance in pts with angina
- May lead to peripheral vasodilation and Orthostatic intolerance
Management of ACS
- ER to ICU to stabilize
- Medical treatment by cardiologist - medications and monitoring
Surgical options for ACS
- Percutaneous Translumial Coronary Angioplasty (PTCA) or Percutaneous Coronary Interventions (PCI)
- CABG - Coronary Artery Bypass Graft
Why would you require a PTCA or PCI as an intervention?
- Persistent chest pain or angina
- Blockage of only 1-2 arteries with severe symptoms
- A change in symptom severity
- Failed medical therapy and worsening of L ventricular dysfunction
What are the surgical options for a CABG ?
- Open heart
- Minimally invasive
Why would you require a CABG as an intervention?
- Presence of triple vessel disease (involves multiple vessels)
- Severe L main artery stenosis
- L coronary artery has a combined 70% or greater stenosis of L anterior descending and proximal left circumflex artery - particularly if L ventricular function is impaired
Potential results of an MI
MI = death of tissue
- Complications depend on extent of damage
- Arrhtyhmias
- Contractile issues
- Wall weakening
- All can lead to decreased cardiac output
Cardiogenic shock
- Death of greater than 40% of LV
- Heart has been damaged so much it’s unable to supply enough blood to the organs of the body
Ventricular Remodeling
- Contractile issues and wall weakening
- With STEMI, changes in shape, size and thickness of myocardium
- Areas of ventricular dilation and ventricular hypertrophy
Factors that affect remodeling
- Size of infarct
- Ventricular load/pressure
- Patency of the artery that was infarcted - how well the artery that was infarcted was functioning
What is the severity of functional impairment related to?
- Left ventricular hypertrophy (determine progression towards HF)
- Conduction defects (increase risk of v-fib or tendency to develop mural thrombosis)
- Smoking, DM, HTN (can continue to accelerate and worsen atherosclerosis)
What is the best predictor of function post ACS?
VO2max
Below what VO2 max indicates the inability to perform ADLs independently and poor prognosis of survival?
Less than 21 mL/kg/min
Mural thrombus
- Clump of atherosclerotic plaque build up
- Thrombi that attach to the wall of a blood vessel and cardiac chamber
Angina and ACS Management
- Control for cardiac pain (-nitrates, morphine, beta blockers)
- Limit necrosis
- Prevent complications
- Thrombolytics/clot busters if within 3 hours of onset
What is the primary concern with medical management of acute coronary syndrome?
Reperfuse that area of the heart not receiving enough blood and oxygen
Sequencing of drugs related to thrombosis and coagulation
- Thrombolytic during ACS to restore blood flow
- Heparin to reduce coagulation rapidly
- Maintenance anticoagulation with warfarin
- Either aspirin or plavix as an Antithrombotic
- Cholesterol lowering drugs to slow atherosclerotic process
Persistent angina and arrhythmias (STEMI)
- Especially V-fib = most common lethal complication
- Death of tissue releases particles that interfere w/ myocardial cell repolarization
- A-fib, heart -block, particularly when affects R side of heart
STEMI and NonSTEMI complications
- CHF: Ejection fraction less than 40%
- Hypertrophy of areas
- Ventricular aneurysm - ballooning out of a weekend LV
- Ventricular wall rupture
- Dyskinesia/Hypokinesia (increased risk of hemostasis)
- Mural thrombus on the damaged wall of LV (Risk of later CVA)
Prognosis for ACS
- Depends on number of vessels involved
- Degree of injury to the heart
- Survival rate long term decreases as the number of vessels involved increases
Signs and symptoms of MI
- History of chest pain
- Shortness of breath
- Diaphoresis
- N&V
- Characteristic changes on EKG (ST segment elevation)
- Enzymes of cardiac myocytes in blood especially CK-MB
Why are enzymes monitored during an MI?
- Either confirm suspicion of MI based on clinical signs
- Diagnose it in the absence of clinical signs
