CHAPTER 23

Cardio: CAD

Coronary Artery Disease (CAD)

Coronary Artery Disease (CAD)

The most prevalent type of cardiovascular disease in adults, characterized by atherosclerosis, which narrows the coronary vessels, reducing blood flow to the myocardium.

Atherosclerosis

Abnormal accumulation of lipid and fibrous tissue in arterial walls, leading to the narrowing of vessels and obstructing blood flow; also known as plaque.

Ischemia

Insufficient tissue oxygenation due to reduced blood supply, leading to myocardial damage and potentially myocardial infarction.

Angina Pectoris

Chest pain caused by myocardial ischemia, often associated with significant coronary atherosclerosis.

Acute Coronary Syndrome (ACS)

Signs and symptoms indicating unstable angina or acute myocardial infarction, requiring immediate medical attention.

Percutaneous Coronary Intervention (PCI)

A procedure using a catheter to reduce blockage within a coronary artery, improving blood flow.

Myocardial Infarction (MI)

Death of heart tissue due to lack of oxygenated blood flow, leading to irreversible damage.

High-Density Lipoprotein (HDL)

Protein-bound lipid that transports cholesterol to the liver for excretion, exerting a beneficial effect on the arterial wall.

Low-Density Lipoprotein (LDL)

Protein-bound lipid that transports cholesterol to tissues, exerting a harmful effect on the arterial wall.

Metabolic Syndrome

Cluster of metabolic abnormalities increasing the risk of cardiovascular disease, including insulin resistance, obesity, dyslipidemia, and hypertension.

Elevated fasting glucose

Fasting glucose levels greater than or equal to 100 mg/dL on two separate occasions or current drug treatment for elevated glucose.

Adipokines

Cytokines released by adipose tissue that can modify insulin action and contribute to atherogenic changes in the cardiovascular system.

C-reactive protein (CRP)

Inflammatory marker for cardiovascular risk, associated with acute coronary events and stroke, produced by the liver in response to stimuli like tissue injury.

Lipoproteins

Proteins that transport fats within the circulatory system, categorized by density based on protein content, including LDL, HDL, VLDL, and chylomicrons.

HDL (High-Density Lipoprotein)

Known as "good cholesterol," it transports other lipoproteins to the liver for degradation and excretion, serving as a protective factor against heart disease.

LDL (Low-Density Lipoprotein)

Known as "bad cholesterol," high levels are associated with advancing coronary artery disease and plaque formation in arterial walls.

Triglycerides

Fatty acids transported by lipoproteins in the blood, elevated levels may result from various factors like genetics, obesity, high-carbohydrate diets, and certain medications.

Physical Activity

Regular exercise helps increase HDL levels, reduce triglycerides, and lower the risk of coronary events and mortality, with recommendations for moderate-intensity aerobic activity for at least 150 minutes per week.

Lipid-lowering medications

Medications like statins, fibrates, bile acid sequestrants, cholesterol absorption inhibitors, and PCSK9 agents used to control cholesterol levels and reduce cardiovascular risk, with considerations for individualized treatment plans and potential adverse effects.

Tobacco use and CAD

Tobacco use contributes to CAD by triggering catecholamine release, increasing LDL oxidation, and reducing oxygen supply to the myocardium, leading to increased risk of CAD and sudden cardiac death.

Cholesterol Absorption Inhibitor

Ezetimibe

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Side effects of Ezetimibe:

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Proprotein Convertase Subtilisin-Kexin Type 9 (PCSK9) Agents

Alirocumab, Evolocumab

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Side effects of PCSK9 Agents:

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Hypertension:

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Diabetes and Heart Disease:

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Angina Pectoris:

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Types of Angina:

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Angina Diagnosis

The process of diagnosing angina involves obtaining the patient's history related to ischemic symptoms, performing a 12-lead ECG to detect ischemic changes, and conducting laboratory studies including cardiac biomarker testing.

Pharmacologic Therapy Objectives

The main goals of medical management for angina are to reduce myocardial oxygen demand and increase oxygen supply, achieved through pharmacologic therapy and risk factor control.

Nitroglycerin

A vasodilator used to improve blood flow to the heart, primarily dilating veins to reduce preload, decrease blood return to the heart, and lower blood pressure, thus reducing myocardial oxygen requirements.

Beta-Adrenergic Blocking Agents

Medications like metoprolol that reduce myocardial oxygen consumption by blocking beta-adrenergic stimulation, leading to decreased heart rate, conduction speed, blood pressure, and myocardial contractility.

Calcium Channel Blockers

Drugs such as amlodipine that decrease heart workload by slowing heart rate, reducing myocardial contraction strength, and dilating coronary arterioles to enhance oxygen supply and decrease oxygen demand.

Antiplatelet Medications

Drugs like aspirin that prevent platelet aggregation, reducing the risk of thrombosis and improving blood flow through the coronary arteries.

Anticoagulants

Medications such as heparin used to prevent new blood clot formation, particularly in unstable angina, by reducing the risk of myocardial infarction and maintaining anticoagulation levels within a therapeutic range.

Glycoprotein (GP) IIb/IIIa agents

Medications like abciximab or eptifibatide administered intravenously to prevent platelet aggregation by blocking the GP IIb/IIIa receptors, reducing intracoronary clot formation.

Oxygen therapy

Initiated during chest pain to increase myocardial oxygen delivery and alleviate pain, monitored by pulse oximetry with normal saturation levels >95% on room air.

Angina assessment

Involves questioning the patient about pain location, description, onset, duration, triggers, relief measures, associated symptoms, and pain intensity on a scale.

Nursing diagnoses for angina

Include risk for impaired cardiac function, anxiety, lack of knowledge about the disease, and ability to perform self-care.

Nursing interventions for angina

Immediate action for pain relief, nitroglycerin administration, oxygen therapy, monitoring vital signs, ECG changes, and assessing for acute MI.

Reducing anxiety in angina patients

Addressing fears, providing information, stress reduction methods, and exploring spiritual needs to alleviate anxiety.

Preventing pain in angina patients

Identifying pain triggers, balancing activity with rest, and educating on lifestyle modifications to minimize anginal episodes.

Home care checklist for angina patients

Includes lifestyle changes, medication adherence, symptom recognition, emergency actions, support resources, and health promotion strategies.

Evaluation of angina management

Expected outcomes include prompt pain relief, decreased anxiety, understanding of complications prevention, adherence to self-care, and stable ECG findings.

Acute Coronary Syndrome (ACS)

Emergent condition with myocardial ischemia leading to MI if not promptly treated, encompassing unstable angina, NSTEMI, and STEMI.

Acute Coronary Syndrome (ACS)

A group of conditions, including unstable angina, NSTEMI, and STEMI, characterized by reduced blood flow to the heart.

Myocardial Infarction (MI)

Commonly known as a heart attack, occurs when blood flow to a part of the heart is blocked, leading to tissue damage.

Electrocardiogram (ECG)

A test that records the electrical activity of the heart, used to diagnose and monitor heart conditions like MI.

Troponin

Cardiac biomarker indicating myocardial injury, specifically used to diagnose acute MI.

ST-segment Elevation

An ECG finding where the ST segment is elevated above the isoelectric line, indicative of acute MI.

Unstable Angina

Chest pain due to reduced blood flow to the heart, without evidence of acute MI on ECG or cardiac biomarkers.

NSTEMI

Non-ST-segment elevation myocardial infarction, diagnosed by elevated cardiac biomarkers without ST-segment elevation on ECG.

STEMI

ST-segment elevation myocardial infarction, diagnosed by characteristic ECG changes indicating significant myocardial damage.

Echocardiogram

Imaging test using sound waves to assess heart function, especially useful when ECG findings are inconclusive.

Creatine Kinase (CK)

Enzyme released when muscle cells, including heart muscle, are damaged, used as a marker for acute MI.

Medical Management

Treatment strategies aimed at reducing myocardial damage, preserving function, and preventing complications in patients with acute MI.

Percutaneous Coronary Intervention

Emergency procedure to open blocked coronary arteries during an acute MI.

Primary PCI

Immediate percutaneous coronary intervention (PCI) performed in the cardiac catheterization laboratory to open the occluded coronary artery and restore blood flow to the oxygen-deprived area in patients with ST-segment elevation myocardial infarction (STEMI).

Thrombolytics

Medications such as alteplase, reteplase, and tenecteplase used to dissolve blood clots in coronary arteries, promoting reperfusion in acute myocardial infarction (MI) when primary PCI is not available within a timely manner.

Door-to-balloon time

The time interval from the patient's arrival in the emergency department to the initiation of PCI, ideally kept under 60 minutes to minimize myocardial cell death due to oxygen deprivation.

ACE Inhibitors

Medications that inhibit the conversion of angiotensin I to angiotensin II, leading to decreased blood pressure, enhanced diuresis, and reduced oxygen demand of the heart, commonly used post-MI to improve outcomes and prevent heart failure.

Cardiac Rehabilitation

A structured program focusing on risk reduction, patient education, physical activity, and psychosocial support for individuals with coronary artery disease (CAD) or those who have experienced an MI, aiming to enhance quality of life and prevent further cardiac events.

Alleviating anxiety and decreasing fear

Important nursing functions that reduce the sympathetic stress response, leading to decreased workload of the heart and potential relief of pain and signs of ischemia.

Risk for impaired cardiac function associated with reduced coronary blood flow

Nursing diagnosis indicating the potential for compromised heart function due to decreased blood flow in the coronary arteries.

Relief of chest pain/discomfort

Goal of nursing interventions aimed at alleviating chest pain and discomfort in patients.

Sympathetic stress response

Physiological reaction involving the sympathetic nervous system that can be reduced through nursing interventions to alleviate anxiety and fear.

Ischemic pain and symptoms

Characteristic clinical findings associated with reduced blood flow to the heart, leading to pain and other symptoms.

Myocardial infarction (MI)

Condition where there is damage to the heart muscle due to reduced blood flow, potentially leading to decreased cardiac output and other complications.

Left ventricular failure

Nursing diagnosis indicating potential impairment in the function of the left ventricle of the heart.

Absence of respiratory distress

Goal of nursing interventions aimed at preventing respiratory distress in patients with left ventricular failure.

Impaired peripheral tissue perfusion

Nursing diagnosis indicating compromised blood flow to peripheral tissues due to impaired cardiac output.

Reduction of anxiety

Goal of nursing interventions focused on decreasing anxiety levels in patients experiencing a cardiac event.

Percutaneous Transluminal Coronary Angioplasty (PTCA)

A procedure using a balloon-tipped catheter to open blocked coronary vessels and improve blood flow within a coronary artery by compressing the atheroma.

Lifestyle Modifications

Changes in daily habits post-myocardial infarction (MI) to promote heart-healthy living, including avoiding chest pain triggers, maintaining a healthy weight, quitting smoking, following a heart-healthy diet, and managing stress.

Cardiac Rehabilitation

A structured program of activity and exercise for long-term rehabilitation post-MI, involving physical conditioning, walking, monitoring pulse rate, and engaging in regular exercise.

Coronary Artery Stent

A metal mesh placed post-PTCA to support the vessel and prevent restenosis, with drug-eluting stents containing medications to reduce thrombi formation, requiring antiplatelet medications for prevention.

Complications of Percutaneous Coronary Interventions

Potential issues during or after PCI procedures, such as myocardial ischemia, bleeding, hematoma formation, retroperitoneal hematoma, arterial occlusion, pseudoaneurysm formation, arteriovenous fistula formation, and acute kidney injury.

Coronary Artery Bypass Graft (CABG)

A surgical procedure where a blood vessel is grafted to an occluded coronary artery to allow blood flow beyond the blockage.

Internal Thoracic Arteries

Arteries recommended for CABG due to their histologic characteristics and increased production of vasoactive molecules, improving arterial patency.

Off-pump Coronary Artery Bypass (OPCAB)

A CABG technique performed without cardiopulmonary bypass, associated with reduced short-term postoperative morbidity.

Complications of CABG

Potential issues post-surgery include hemorrhage, arrhythmias, and myocardial infarction, requiring multidisciplinary collaboration for management.

Preoperative Management for CABG

Includes the use of aspirin, beta-blockers, and statins to improve outcomes and prevent complications in older patients with comorbidities undergoing surgery.

Surgical trauma

Causes tissues and blood vessels to ooze bloody drainage.

Intraoperative anticoagulant therapy

Involves the use of heparin during surgery to prevent blood clotting.

Postoperative coagulopathy

May result from liver dysfunction and depletion of clotting components after surgery.

Accurate measurement of wound bleeding

Essential to monitor and ensure proper healing post-surgery.

Administration of blood products

Includes packed red blood cells, fresh frozen plasma, platelet concentrate, and recombinant factor VII.

Cardiac tamponade

Accumulation of fluid and clots in the pericardial sac, compressing the heart.

Hypothermia

Low body temperature leading to vasoconstriction and shivering.

Hypertension

Results from postoperative vasoconstriction, may stretch suture lines and cause bleeding.

Tachyarrhythmias

Increased heart rate common post-surgery, may require medications like amiodarone or diltiazem.

Bradycardias

Decreased heart rate due to surgical trauma, may require external pacemaker or medications like atropine.