Cardiovascular 3

• Atherosclerosis is a type of blood vessel disorder. It beings as soft deposits of fat that harden with age and is referred to as the hardening of the arteries. It can occur in any artery of the body but the coronary arteries are the most at risk.
• The major cause of CAD is atherosclerosis
• Atherosclerosis has 4 stages:

  • chronic endothelial injury
  • fatty streak
  • fibrous plaque
  • complicated lesion
• Chronic endothelial injury can be caused by hypertension, tobacco use, hyperlipidemia, diabetes, infections and toxins
• Fatty streak is when lipids accumulate and migrate into smooth muscle cells
• Fibrous plaque is when collagen covers the fatty streak. The vessel lumen is narrowed which reduces blood flow and fissures can develop
• A complicated lesion is when the fibrous plaque ruptures. It forms a thrombus and further narrows or occluses the vessel which causes MI and unstable angina
• Coronary artery disease is a perfusion problem since it affect the blood vessels
• Collateral circulation is the arterial connections that exist within the coronary circulation. Their growth is attributed to genetics (angiogenesis) and presence of chronic ischemia (inadequate blood supply)
• Ischemia is the inadequate blood supply vs infarction is cell death
• Non modifiable risk factors for CAD

  • age
  • gender (men have increased risk)
  • ethnicity
  • family history of heart disease
• Modifiable risk factors for CAD

  • serum lipid alterations like increased cholesterol
  • hypertension
  • tobacco use
  • physical inactivity
  • obesity
  • diabetes
• Metabolic syndrome are a group of risk factors that increase the risk for heart disease. They include low HDL cholesterol, high waist circumference and elevated BP
• Health promotion for CAD

  • physical fitness (150 minutes of moderate intensity physical activity per week)
  • nutritional therapy (low saturated fat)
  • smoking cessation
  • cholesterol lowering drug therapy
  • antiplatelet therapy
• Chronic stable angina is chest pain that occurs intermittently with the same pattern of onset, duration and intensity of symptoms
• Angina is a demand for oxygen that exceeds the supply of oxygen. This causes pain, often in the chest, which may be related to resp, cardio, GI or musculoskeletal system
• Chronic stable angina is a reversible myocardial ischemia resulting from an increased demand of oxygen compared to its supply. The primary reason for insufficient blood flow (oxygen) is the narrowing of coronary arteries by atherosclerosis
• Factors that decrease oxygen supply

  • atherosclerosis in coronary arteries
  • coronary artery spasm
  • hypovolemia (not enough blood volume)
  • hypoxemia (low oxygen)
  • anemia (low RBC)
  • coronary artery thrombosis
• Factors that increase oxygen demand

  • anxiety
  • hyperthermia
  • physical exertion
• Clinical manifestations for chronic stable angina are chest pain, pressure or ache in the chest, squeezing and tightness sensation
• Characteristics of chronic stable angina

  • usually does not change with position or breathing
  • pain is brief (3-5 min)
  • commonly subsides when precipitating factor is relieved
  • pain at rest is unusual
  • pain relieved by rest or nitroglycerin
• Locations of chest pain

  • back, shoulders, chest, neck, jaw
• Atypical angina manifestations: fatigue, dyspnea, syncope (fainting) with exertion, epigastric sensations such as nausea or vomiting, indigestion
• Unstable angina is caused by the rupture of plaque exposing thrombogenic surface. It is refractory to nitroglycerin
• Diagnostic tests:

  • serum lipids: HDL, LDL, triglycerides
  • ECG
  • holter monitor
  • exercise stress test
• Nursing management for angina

  • monitor vital signs
  • 12-lead ECG
  • comfortable positioning
  • prompt pain relief with a nitrate followed by an opioid analgesic if needed
• Education on angina

  • provide information regarding precipitating factors
  • address concerns such as anxiety
  • discuss self management skills
  • lifestyle changes such as smoking cessation and healthy diet with control of lipid and alcohol
  • advise patients to seek urgent help if angina worsens suddenly