Perfusion: CAD, Heart Failure, and Pharmacology

• The core concept is perfusion.
• The exemplars include Coronary Artery Disease and Congestive Heart Failure.

Perfusion Principles:

• Understand risk factors and prevention related to perfusion alterations.
• Be familiar with perfusion diagnostic testing and clinical judgment.
• Understand Coronary Artery Disease, Congestive Heart Failure, and Myocardial Infarction.

Pharmacology of Perfusion:

• Use antianginals (Nitrates).
• Use antilipemics such as Bile acid sequestrants, Fibrates, HMG CoA reductase inhibitors, Nicotinic acid, Cholesterol absorption inhibitors, and Omega 3.
• Use cardiac glycosides like Digoxin and Digoxin immune fab.
• Use aspirin, beta blockers, calcium channel blockers, and thrombolytics.
• Use Angiotensin Converting Enzyme Inhibitors/Angiotensin II Receptor Blockers.

Learning Objectives:

• Recognize the etiology and pathophysiology of coronary artery disease (CAD), acute coronary syndrome (ACS), and heart failure (HF).
• Identify risk factors contributing to CAD, ACS, and HF.
• Analyze client's clinical manifestations and prioritize nursing interventions for CAD, ACS, and HF.
• Interpret diagnostic studies for diagnosing CAD, ACS, and HF.
• Implement solutions that address the highest priority.
• Recognize the importance of an interdisciplinary team when caring for clients with CAD, ACS, and HF.
• Implement a nursing education plan for clients with CAD, ACS, and HF.
• Compare and contrast pharmacological management for patients with CAD, ACS, and HF.

Perfusion Defined:

• The passage of fluid (such as blood) through a specific organ or area of the body (such as the heart).
• Cardiac Output (CO) = Stroke Volume x Heart Rate.
• The amount of blood that the heart pumps into the circulatory system in 1 minute maintains tissue perfusion.
• Preload is the amount ventricles stretch at the end of the relaxation phase (Diastole), or the end diastolic volume.
• Afterload is the pressure/load needed to open the valves (Pulmonary and Aortic Valve).

Coronary Artery Disease (CAD):

• CAD is also called Atherosclerotic Heart Disease.
• CAD occurs when major blood vessels that supply the heart are damaged or diseased.
• CAD can be caused by lipid-containing deposits (plaques) which build up in the coronary arteries; This causes narrowing or obstruction of blood flow to the myocardial tissue.
• Lack of perfusion to the myocardial tissue and inadequate oxygen supply lead to hypertension, angina, dysrhythmias, myocardial infarction (MI), heart failure and death.
• CAD occurs over a long duration of decades.

CAD Risk Factors

• Non-modifiable risk factors include:
  • Increasing age. >45 for men, >55 for women
  • Family history of coronary heart disease.
  • Men > premenopausal women.
  • Post-menopausal women.
  • Race. White males show the highest incidence of CAD and mortality.
• Possible risk factors include:
  • Sleep apnea
  • Autoimmune disorders
  • Alcohol use
  • Pre-eclampsia
• Modifiable risk factors include:
  • Elevated serum cholesterol.
  • Smoking/Nicotine inhalation
  • Hypertension (BP > 120/80).
  • Diabetes Mellitus
  • Physical inactivity.
  • Obesity (BMI ≥30); waist >40" men, 35" women.
  • Metabolic Syndrome (central obesity, HTN, abnormal lipids, >fasting glucose level).
  • Oral contraceptive use or hormone replacement therapy.
  • Substance abuse - stimulants such as methamphetamine or cocaine, which increase HR and cause vasoconstriction.

CAD Assessment:

• Includes asymptomatic periods
• Assess for chest pain
• Assess for paroxysmal "sudden" chest pain, which can is intermittently caused by physical or emotional stress leading to myocardial ischemia.
• Check for:
  • Palpitations
  • Dyspnea or Shortness of Breath
  • Syncope
  • Cough or hemoptysis.
  • Excessive fatigue

Angina Pectoris:

• Angina pectoris is chest pain caused by myocardial ischemia.
• Any factor that increases oxygen demand or decreases oxygen supply may deprive the myocardium of necessary oxygen needed to function effectively.
• Physical exertion and sexual activity can cause angina pectoris.
  • Increases heart rate and reduces diastole (time of maximum blood flow to the myocardium).
• Intense emotion and anxiety can cause angina pectoris.
  • Initiates the sympathetic nervous system and increases cardiac workload
• Temperature extremes can cause angina pectoris.
  • Usually cold exposure and hypothermia (vasoconstriction); occasionally hyperthermia (vasodilation and blood pooling)
• Tobacco use and second-hand smoke inhalation can cause angina pectoris.
  • Replaces oxygen with carbon monoxide; nicotine causes vasoconstriction and catecholamine release
• Stimulants (cocaine, amphetamines) can cause angina pectoris.
  • Increase heart rate and cause vasoconstriction
• Coronary artery narrowing (atherosclerosis, coronary artery spasm) decreases blood flow to myocardium, which can cause angina pectoris.

CAD Diagnostic Testing:

• Lipoprotein profile measures Total Cholesterol, low-density lipoprotein (LDL), high-density lipoprotein (HDL), and triglycerides.
• Chest X-ray will show increased density of lungs and size of the heart.
• Electrocardiogram (ECG/EKG) is a graphic representation of electrical activity that occurs in the heart.
• Echocardiogram is a noninvasive ultrasound of the heart
• Cardiac Catheterization uses contrast and a long flexible catheter to visualize the heart chambers, coronary arteries and great vessels.
• Stress Test (Exercise ECG) is a non-invasive study of heart during activity. It detects and evaluates for CAD. This includes a Treadmill or IV infusion of dipyridamole or Dobutamine HCL.
• Cardiac CT assesses calcium deposits in the vessels. Does not check specific Blockages.
• Normal cholesterol levels:
  • Total Cholesterol: 125-200 mg/dL
  • LDL: <130 mg/dL
  • HDL (Men): >45 mg/dL
  • HDL (Women): >55 mg/dL
  • Triglycerides (Men): <160 mg/dL
  • Triglycerides (Women): <135 mg/dL

CAD Treatment:

• Smoking/Nicotine Cessation
• Exercise: Aim for 30-60 minutes 5 days/week.
• Weight Loss
• Dietary Changes: follow a low-calorie, low-sodium, low-cholesterol, low-fat diet, with increase in Omega-3 fatty acids such as salmon, albacore tuna, mackeral or supplements; also increase dietary fiber.
• Reduce alcohol intake
• Stress Reduction
• Medications for treatment include cholesterol-modifying and antilipemic medications.
  • HMG-CoA reductase inhibitors/Statins:
    • Atorvastatin (Lipitor)
    • Simvastatin (Zocor)
    • Rosuvastatin (Crestor)
      • Adverse Effects: Abd pain, headache, rash, myopathy (muscle pain) progress to Rhabdomyolysis-ARF. Check Liver Function tests.
      • AVOID GRAPEFRUIT JUICE. It inactivates enzyme CYP3A4, which metabolizes statin, resulting in drug toxicity.
      • Take with dinner or HS.
    • Bile Acid Sequestrants such as Cholestyramine (Questron).
      • Adverse Effects: Constipation, heartburn, nausea,belching and bloating
    • Niacin (nicotinic acid, Vitamin B3).
      • Adverse Effects: Flushing, pruritus, and gastrointestinal distress. Small doses of ASA or NSAIDs may be taken 30 minutes before dose to minimize flushing.
    • Fibric Acid Derivatives (Fibrates) include Gemfibrozil and Fenofibrate.
      • Adverse Effects: Abdominal discomfort, nausea, diarrhea, headache, blurred vision, increased risk for gallstones, prolonged prothrombin time -Aspirin (antiplatelet). Monitor platelets, signs of bleeding -Anti-Anginal Medications should include Beta Blockers.
      • Beta Blockers:
        • Atenolol (Tenormin)
        • Carvedilol (Coreg)
        • Labetalol (Normodyne, Trandate)
        • Metoprolol (Lopressor, Toprol XL)
        • Propranolol (Inderal, Inderal LA)
          • Adverse Effects: Bradycardia, depression, impotence, and fatigue; abruptly stopping can result in rebound HTN, angina, palpitations, MI, arrhythmias (tachycardia, ventricular tachycardia), or sudden death.
          • Check an apical pulse before administering. HOLD if HR < 50 (adult). Check the patient's history (COPD, Asthma?) dt bronchoconstriction
    • Calcium Channel Blockers (CCBs).
      • Amlodipine
      • Diltiazem
      • Nicardipine
      • Nifedipine
      • Verapamil
        • Adverse Effects: Hypotension, palpitations, tachycardia or bradycardia, constipation, nausea, flushing, peripheral edema. AVOID GRAPEFRUIT. Grapefruit can slow the metabolism of calcium channel blockers leading to increased serum concentrations and adverse effects (severe hypotension, organ dysfunction). -Nitrates: cause vasodilation on large and small coronary arteries, relaxes venous and arterial smooth muscle which decreases SVR and Pulmonary vascular resistance.
      • Nitroglycerin often abbreviated NTG (Nitro-Bid, Nitrostat, Nitrol)
      • Isosorbide dinitrate (Isordil, Dilatrate-SR)
      • Isosoride mononitrate (Imdur, Monoket)
        • Adverse Effects: Headache, tachycardia, postural hypotension, contact dermatitis (topical). Never take Nitrate/Nitrite with Sildenafil/Viagra (PDE-5 inhibitor- vasodilator cause Hypotension).
        • Sublingual administration: After 1st tablet if pain not relieved call 911. May repeat up to 3 tablets in a 15-min period, 1 tablet every 5 minutes
        • Transdermal patch: Off for 8-12 hours before applying new patch. Apply to a new site, cover with plastic wrap (occlusive) and secure with tape. Do not use your fingertips!
    • Angiotension-Converting Enzyme (ACE) Inhibitors used for Heart Failure and Hypertension, which decreases SVR. Examples include:
      • Enalapril (Vasotec)
      • Lisinopril (Prinivil)
      • Captopril (Capoten)
        • Adverse Effects: Fatigue, dizziness, mood changes, headaches, loss of taste, angioedema, hyperkalemia, renal impairment, and a characteristic dry nonproductive cough;Salt substitutes contain high potassium and must not be consumed unless approved by the health care provider (HCP) when taking an ACE Inhibitor or ARBs.
    • Angiotension II Receptor Blockers (ARBS):
      • Losartan (Cozaar)
      • Irbesartan (Avapro)
      • Valsartan (Diovan)
        • Adverse Effects: Chest pain, fatigue, hypoglycemia, diarrhea, UTI, anemia, and weakness. Hyperkalemia and cough can occur, less likely than ACE inhibitors.
    • Diuretics: Will be discussed under Heart Failure is used to treat HTN Also include:
      • Stool softeners/Laxatives(Lilley & Snyder, et. al., [2023], page. 806)
        • Categories:
          • Bulk-forming. psyllium, methylcellulose
          • Emollient. docusate salts, mineral oil
          • Hyperosmotic. polyethylene glycol, lactulose, sorbitol, glycerin
          • Saline. magnesium hydroxide, magnesium sulfate, magnesium citrate
          • Stimulant. senna, bisacodyl

Myocardial Infarction:

• STEMI is an ST-elevation on the ECG. This is caused by an occlusive thrombus, and is a medical emergency. The artery must be opened within 90 minutes to restore blood and oxygen to heart muscle and reduce size of infarct.
  • Can be treated with Cardiac Catheterization with Percutaneous coronary intervention (PCI), or balloon angioplasty with stents. or Thrombolytic therapy-Tenecteplase, Alteplase (IV).
• STEMI does have ST segment elevation on ECG, this is caused by a non-occlusive thrombus. The treatment is Cardiac catheterization within 12-72 hours. With either a NSTEMI or STEMI an echocardiogram may show hypokinesis, which is worsening myocardial contractility, or akinesis, which is absent myocardial contractility in the necrotic area(s).
• Most MIs affect the left ventricle.

Clinical Manifestations of MI:

• Severe chest pain not relieved by rest, position change, or nitrate administration.
• Pain is described as: Heavy, pressure, tight, burning, or crushing.
• Substernal or epigastric pain may radiate to neck, jaw, arms or back
• Pain may feel like indigestion, NOT relieved by antacids, with nausea and vomiting
• Occurs while active or at rest
• Women-atypical discomfort, SOB or fatigue
• Patients with Diabetes may be asymptomatic

Diagnostic Studies: Acute Coronary Syndrome:

• Electrocardiogram (ECG): Changes in the QRS complex, ST segment, and T wave caused by injury, ischemia, and infarction (whenever possible compare to previous ECG)
• Serum Cardiac Biomarkers: Proteins released into the blood from the necrotic heart muscle (cardiac-specific troponin T [cTnl] greater than 0.4 ng/mL indicative of cardiac injury, creatine kinase MB [CK-MB], Myoglobin)
• Cardiac Catheterization: Goal to open the totally occluded artery and limit the infarction size

Drug Therapy for MI:

• Use Thrombolytic therapy such as Tenecteplase, Alteplase / Tissue Plasminogen Activator [t-Pa]
• Use IV Nitroglycerin to reduce angina pain & improve coronary blood flow. Monitor BP closely.
• Use Morphine: Vasodilator, decreases cardiac workload. lowers myocardial oxygen consumption, and reduces anxiety. Monitor for s/s Respiratory Depression.
• Use Beta-blockers: Decreases myocardial demand by reducing HR, BP and contractility.
• Use antidysrhythmic Medications for Dysrhythmias.
• Use Lipid-lowering Drugs
• Use Stool Softeners: docusate sodium (Colace) prevent straining and resultant vagal stimulation from the Valsalva maneuver-bradycardia

ACS/STEMI Nursing Interventions:

• Start on Telemetry
• Apply oxygen to increase the oxygen to the heart muscle, especially if oxygen saturation <90%
• Start 1-2 large bore (18 gauge) IVs
• Draw to cardiac enzymes
• Use IV Nitroglycerin for faster route vasodilation
• Use IV Morphine
• Cardiac Catheterization/Percutaneous Coronary Intervention (PCI) would likely be performed within 90 minutes for a STEMI
• If at a hospital that cannot perform a PCI arrange for transport ASAP, may start IV thrombolytics

Congestive Heart Failure (CHF)

• Can be left-sided versus right-sided.
• Can be classified as systolic versus diastolic heart failure.

Heart Failure

• Heart Failure is a complex clinical syndrome that develops in response to myocardial insult; Secondary disease result of another condition
• It is the inability of the heart to provide sufficient blood to meet the oxygen needs of the tissues and organs.
• Decreased cardiac output leads to decreased tissue perfusion, impaired gas exchange, fluid volume imbalance, and decreased functional ability
• Left ventricular ejection fraction (LVEF): Amount of blood (percentage) in the left ventricle (LV) at the end of the relaxation phase (diastole) that is pumped out of the LV with the next systole
• Heart Failure with reduced ejection fraction (HFrEF): LVEF <40%
• Heart Failure with preserved ejection fraction (HFPEF): LVEF >50%

Heart Failure Ejection Fraction:

• Normal Ejection Fraction ranges from 55% to 70%
• Ejection Fraction 40% to 54%: Pumping Ability of the Heart: Slightly below normal
• Ejection Fraction 35% to 39%: - Pumping Ability of the Heart: Moderately below normal - Level of Heart Failure/Effect on Pumping: Mild heart failure with reduced EF (HF-rEF).
• Ejection Fraction less than 35%: - Pumping Ability of the Heart: Severely below normal. - Level of Heart Failure/Effect on Pumping: Moderate-to-severe HF-rEF. Severe HF-rEF increases risk of life-threatening heartbeats and cardiac dyssynchrony (right and left ventricles do not pump in unison).

Classifications of Heart Failure

• New York Heart Association (NYHA) Classes of Heart Failure: Categories (I-IV) based on physical activity limitations due to symptom burden
• American College of Cardiology Foundation and the American Heart Association (ACCF/AHA): Staging system (A-D) emphasizes the evolution and progression of heart failure as well as treatment strategies. (Does patient have structural heart disease? Symptoms?)
• Acute Heart Failure: rapid onset of disease, often in the context of pre-existing cardiomyopathy (viral, drug-induced, PE, pericardial effusion)
• Chronic Heart Failure: Long-term condition that gets worse over time.
• Diastolic Heart Failure: Decreased filling/relaxation of the ventricle; thickened ventricular wall. Can have a normal EF.
• Systolic Heart Failure: Inability to pump with enough force (decreased contractility = decreased inotropy) EF≤40

Heart Failure Risk Factors

• Coronary Artery Disease (CAD)
• Hypertension
• Diabetes Mellitus
• Obesity
• Sleep Apnea
• Alcohol Use
• Medications used to treat conditions or co-morbidities
• Valve Disease (incompetent): Stenosis or Regurgitation
• Dilated Cardiomyopathy
• Myocardial Infarction
• Arrhythmias

Manifestations of Heart Failure:

• Right-Sided Heart Failure signs are:
  • Right ventricular heaves
  • ↑ HR
  • Murmurs
  • Jugular venous distention
  • Edema: pedal, scrotum, sacrum
  • Weight gain
  • Ascites
  • Anasarca
  • Hepatomegaly
• Left-Sided Heart Failure signs include:
  • Left ventricular heaves.
  • ↑ HR
  • Pulsus alternans
  • PMI displaced inferiorly and left of the midclavicular line.
  • ↓ PaO2, slight ↑ PaCO2 (poor O2 exchange)
  • Crackles
  • S3 and S4 heart sounds
  • Pleural effusion
  • Changes in mental status
  • Restlessness, confusion
  • Shallow respirations
  • Dry, hacking cough
  • Frothy, pink-tinged sputum.
• Right-Sided Heart Failure Symptoms: are:
  • Fatigue
  • Anxiety, depression
  • Right upper quadrant pain
  • Anorexia and GI bloating
  • Nausea
• Left-Sided Heart Failure Symptoms.
  • Weakness, fatigue
  • Anxiety, depression
  • Dyspnea
  • Paroxysmal nocturnal dyspnea
  • Orthopnea
  • Nocturia
• Right-sided HF is when Fluid backs up into the abdomen, legs, and feet causing edema
• Left-sided HF is when Fluid may back up in the lungs, causing shortness of breath
• With Chronic CHF, patients may experience clinical manifestations of both right-sided (systemic venous congestion) and left-sided (pulmonary congestion) failure

Heart Failure Testing:

• b-Type natriuretic peptide (BNP): Peptide that causes natriuresis
• NT-Pro-BNP: A protein secreted by the ventricular musculature in response to volume or pressure overload. Results >100 picograms/milliliter (pg/mL)
• CK-MB: Tests for myocardial cell injury
• Troponin (cardiac): Test for cardiac injury and ischemia
• C-reactive protein (CRP): Marker of inflammation
• CBC, CMP & Lipid panel
• ECG, Holter monitor (24-48 hours), ECG event recorder
• Echocardiogram, Stress Echo
• Imaging: Chest x-ray, Cardiac CT scan, Cardiac MRI, Magnetic resonance angiography (MRA)
• Exercise/Stress Test
• Cardiac Catheterization/Angiogram

Congestive Heart Failure Goals of Therapy

• Supporting oxygenation, ventilation, cardiac output, and end organ perfusion
• Identifying and addressing the cause of the heart failure
• Symptom relief
• Optimizing volume status
• Avoiding complications
• Providing patient/family teaching addressing factors that precipitate HF exacerbations
• Patient Education with an Interdisciplinary Team- Primary Care & Specialty Care, the patient needs to be educated on when to notify provider, Prescriptions, over-the-counter meds, and supplements. The patient should follow a diet low in sodium, between 1.5-2 grams/day, reading labels

Medications for Congestive Heart Failure:

• Angiotension-converting enzyme (ACE) inhibitors
  • Benazepril (Lotensin)
  • Captopril (Capoten)
  • Enalapril (Vasotec)
• Angiotension II Receptor Blockers
  • Losartan (Cozaar)
  • Valsartan (Diovan)
• Beta Blockers
  • Metoprolol succinate (Toprol XL)
  • Bisoprolol (Zebeta)
  • Carvedilol (Coreg)
• Neprilysin-Angiotensin Receptor Inhibitor
  • Sacubitril/valsartan (Entresto)
• Diuretics include:
  • Loop Diuretics: Furosemide (Lasix), Bumetanide (Bumex), torsemide
  • Thiazide Diuretics: Hydrochlorothiazide, Metolazone (Zaroxolyn)
  • You must assess BP, electrolytes, kidney function (BUN/creatinine)
• Aldosterone Antagonists (Potassium-sparing Diuretics)
  • Eplerenone (Inpra)
  • Spironolactone (Aldactone)
  • You must assess BP, electrolytes, kidney function (BUN/creatinine)
• Positive Inotropes are:
  • Beta-Adrenergic Agonists: Dobutamine, Dopamine
  • Phosphodiesterase inhibitor: Milrinone
  • Cardiac Glycoside (Digoxin)
• Digitalis (Digoxin is a weak positive inotrope and you must hold if HR < 60/min adult or < 70/min for child or <90/min for an infant .
  • Adverse Effects: Bradycardia or tachycardia, hypotension, Headache, fatigue, confusion, convulsions, Colored vision, GI disturbances, Anorexia, nausea,vomiting, diarrhea
  • Digoxin Toxicity Causes include low potassium, low magnesium, decreased renal function, and hypothyroidism. Symptoms and signs include: Bradycardia, Headache, Dizziness, Confusion, Nausea, blurred or yellow vision,Heart block or ventricular dysrhythmias
  • Treatment: Digoxin Immune Fab, it recognizes digoxin as an antigen and forms an antigen-antibody complex with the drug, thus inactivating the free digoxin. It is indicated only for hyperkalemia in a patient with Digoxin toxicity or if the patient has life-threatening cardiac dysrhythmias, sustained ventricular tachycardia or fibrinillation, and severe sinus bradycardia or heart block unresponsive to atropine treatment or cardiac pacing with a life-threatening digoxin overdose of more than 10 mg digoxin in adults and more than 4 mg digoxin in children.

Complications of Congestive Heart Failure:

• Pleural Effusion: Fluid between the two tissue layers (pleura) that covers the lung and line the chest wall.
• Dysrhythmias
• Atrial and Ventricular
  • Ventricular Tachycardia, Ventricular Fibrillation.
  • Patients may need an Implantable cardioverter-defibrillator (ICD) to treat arrhythmias.
• Severe Hepatomegaly: Impaired liver function lead to Cirrhosis
• Cardiorenal Syndrome: Decreased renal perfusion, impaired function
• Anemia: Reduced erythropoietin production in kidney
• Patients may have Mechanical Circulatory Support Devices such as Bridge to Transplant Ventricular Assist Devices in the left, right, or both ventricles.

Perfusion Nursing Considerations:

• The provider should be notified for any change in status or assessment.
• Obtain orders for labs, ECG, Imaging, consults
• Insure that you have a good IV
• Pay attention to labs, weights, and subtle changes
• Patient may be anxious or have a sense of doom.
• Treatment inlcudes ABC's and medications, which should be administered as ordered.