Study Notes on Coronary Artery Disease Lecture by Miss Buchanan

Cardiovascular Lecture on Coronary Artery Disease

Introduction

• Presenter: Miss Buchanan

• Lecture Format: PowerPoint available on Blackboard, recommended for better interaction.

Objectives of the Lecture

• Discuss the effects of normal aging on the cardiovascular system.

  • Aging impacts the heart's efficiency as a pump by age 65.

  • Heart can function adequately unless there is underlying cardiac disease.

• Importance of routine cholesterol checks for adults over 20 (recommended every 4 to 6 years according to the American Heart Association).

• Older adults with high cholesterol should adopt lifestyle changes and medications to lower cholesterol, including:

  • Cholesterol medications

  • Smoking cessation

  • Increased activity levels

  • Blood pressure medications

  • Weight loss

  • Control of blood glucose levels

Risk Factors for Cardiac Disease

• Modifiable Risk Factors (can change through lifestyle modifications):

  • Smoking

  • Hyperlipidemia (high cholesterol levels)

  • Hypertension (high blood pressure)

  • Type 2 diabetes

  • Obesity

  • Sedentary lifestyle

  • Stress and psychosocial factors

• Non-modifiable Risk Factors (cannot change):

  • Family history

  • Age

  • Past lifestyle habits

  • Gender

  • Cultural and ethnic considerations

Coronary Arteries Overview

• Coronary arteries' location: Run along the epicardial surface of the heart, supplying the heart muscle with oxygen-rich blood and nutrients.

• Origin: Derived from the base of the aorta.

  • Right coronary artery: Originates above the right cusp of the aortic valve.

  • Left coronary artery: Originates above the left posterior cusp of the aortic valve.

• Size: Diameter of about 1/8 inch.

• Functionality: Supply nutrients by curving around the heart muscles and bifurcating toward the apex.

• Vulnerability: Susceptibility to atherosclerotic changes due to structural characteristics.

Coronary Artery Disease (CAD)

• Definition: CAD involves diseased or damaged arteries supplying the heart, being the leading cause of death in the U.S.

• Statistics (2017): 42.6% of deaths attributed to cardiovascular disease were due to CAD.

• Incidence: Every 40 seconds, an American suffers from a myocardial infarction (MI) related to CAD.

• Types of Causes of CAD:

  • Obstructive CAD: Most commonly due to atherosclerotic changes within coronary arteries.

  • Non-obstructive CAD: Other causes not due to physical blockages.

Pathophysiology of Atherosclerosis

• Healthy arteries vs. atherosclerosis:

  • Known for yellowish plaques of cholesterol, lipids, and cellular debris affecting coronary arteries.

• Causes:

  • Damage to the endothelium from high blood pressure, tobacco smoke, and other disease processes (inflammation).

• Progression:

  • Inflammatory responses lead to plaque formation, narrowing arteries, and hindering blood flow.

  • Risk of plaque rupture, leading to blockage.

Symptoms of Ischemic Heart Disease

• Vary based on plaque size, location, and obstructions.

• Most common symptom: Myocardial ischemia, presenting as chest pain or angina pectoris.

• Definition of Ischemia: Condition where heart muscle does not receive enough blood, causing oxygen deprivation.

• Angina pectoris symptoms:

  • Described as a cramp-like choking feeling with thoracic pain related to decreased oxygen flow to the myocardium.

• Types of Angina:

  • Stable Angina: chest pain during activity, alleviates with rest/nitroglycerin.

  • Unstable Angina: increased severity/frequency of pain not relieved by rest/nitroglycerin, indicative of a pending heart attack.

  • Variant Angina: coronary artery spasm during rest.

Clinical Manifestations of Myocardial Ischemia

• Pain characteristics: Can range from mild discomfort to severe pain, often described as pressure, burning, squeezing, or fullness.

• Location: Typically poorly localized, deep behind the sternum; may radiate to neck, jaw, left arm.

• Non-pain symptoms may include:

  • Mild indigestion

  • Shortness of breath

  • Nausea and vomiting

  • Pallor and diaphoresis

  • Dizziness/lightheadedness

• Distinctions in symptoms for women: Often less chest pain, instead experiencing nausea, fatigue, indigestion, and discomfort in the back/abdomen.

• Impact of diabetes on symptoms: May cause decreased sensation, masking chest pain due to neuropathy.

Assessment of Chest Pain

• Subjective Data: Information shared by the patient regarding new or worsening chest pain.

  • Details to gather: Location, intensity, duration, radiation, precipitating factors, relieving factors.

• Objective Data: Observable signs and symptoms during physical assessment.

  • Behaviors: Gestures like clutching chest, vital signs (heart rate, blood pressure), signs of anxiety or perspiration.

Diagnostic Tests and Management

• Essential tests for chest pain diagnosis:

  • EKG: Determines heart rhythm and identifies heart attacks, must be conducted within 10 minutes.

  • Labs: Includes cardiac enzymes to differentiate heart attacks from coronary artery disease effects.

  • Cath Lab: for coronary angiography to locate blockages.

• Medical Management Goals:

  • Control symptoms and reduce ischemia.

  • Identify and eliminate precipitating factors.

  • Modifiable cardiovascular risks correction through medication and lifestyle changes.

Treatment of Angina Pectoris

• Main medication: Nitroglycerin - a vasodilator.

  • Patients need to carry this continuously if history of angina.

• ER treatment: IV nitroglycerin, anticoagulants, and oxygen therapy for demand relief.

• Additional medications: Beta-blockers and calcium channel blockers for reducing workload and improving blood flow.

• Nursing interventions:

  • Comfort measures and anxiety reduction.

  • Tissue perfusion promotion through controlled activity levels.

  • Educate on recognizing symptoms and responding to signs of escalating pain.

Prognosis and Complications of CAD/MI

• Prognosis depends on factors like age, diabetes, comorbid conditions, and lifestyle modifications adherence.

• Potential outcomes: Some patients may remain stable for years, others may progress toward MI.

• Myocardial Infarction (MI): Necrosis of heart muscle due to reduced/ceased blood flow.

• Clinical manifestations of MI: Pain significantly more severe than angina, prolonged duration, described variably (crushing, heavy, vice-like).

• Statistics: Most MIs caused by atherosclerotic plaques (70%); women often have modifiable risk factors.

MI Management and Nursing Care

• Key diagnostics upon presenting with chest pain:

  • First Response: EKG within 10 minutes; interpret ST elevation.

  • Lab tests: Troponin I – critical for diagnosing heart attack (rises within 3 hours, peaks at 12).

  • Prepare for potential PCI: Gold standard for acute management.

• Protocol: MONA (Morphine, Oxygen, Nitroglycerin, Aspirin) initiated upon suspected MI.

• Procedures:

  • PCI: A minimally invasive procedure for managing CAD, involves stenting.

  • CABG (Coronary Artery Bypass Grafting): for severe angina with significant narrowed arteries, involving grafting additional blood vessels.

  • Postoperative Monitoring: Complications like stroke, infection, graft failure, and renal failure are risks of CABG.

Nursing Interventions for CAD Patients

• Post catheterization monitoring for adequate tissue perfusion, infection prevention, and emotional support.

• Patient Education: risk factor modification, lifestyle changes, and adherence to medication regimens are critical for prognosis improvement.

• Importance of early recognition and intervention in chest pain to minimize ischemic damage and enhance recovery outcomes.