Peripheral Vascular Disorders Study Notes

Chp 27 & 30

Introduction to Peripheral Vascular Disorders
  - Focus on three key areas:
    - Peripheral Arterial Disease
    - Pulmonary Embolism
    - Abdominal Aortic Aneurysms

Cardiovascular System Assessment
  - Assessment chapter details are crucial for understanding heart function.
  - Focus on pages 636 to 652 as outlined in the syllabus.
  - Key concepts include:
    - Perfusion
    - Oxygenation
    - Electrolyte Management

Cardiac Output (CO)
  - Definition: Amount of blood pumped by the heart per minute.
  - Average CO: 3 to 6 liters/minute.
  - Calculation: CO = Stroke Volume (SV) × Heart Rate (HR)
    - Stroke Volume: Volume of blood ejected by the left ventricle in one contraction.
  - Importance: Determines efficiency of perfusion, particularly in patients post-myocardial infarction (MI) or undergoing cardiac surgery.
Preload and Afterload
  - Preload: Volume of blood in the ventricles at the end of diastole.
    - Affected by venous return and ventricular compliance.
  - Afterload: Pressure the ventricles must overcome to eject blood during systole, influenced by vascular resistance.
    - Medications can alter preload or afterload (e.g., diuretics for preload, vasodilators for afterload).

Arterial System
- Function: Delivers oxygen and nutrients to tissues; aids in temperature regulation.
- Structure: Composed of arteries, arterioles, capillaries.
Venous System
- Function: Returns deoxygenated blood to the heart; serves as a fluid reservoir.
- Structure: Composed of veins, venules.

Definition: Force exerted by circulating blood on vessel walls, measured primarily in arteries.
  - Components:
    - Systolic Pressure: Pressure during ventricular contraction (higher number).
    - Diastolic Pressure: Pressure during ventricular relaxation (lower number).
  - Normal Blood Pressure: 120/80 mmHg (varies with age).
    - Hypertension: >140 systolic or >90 diastolic; changes over time observed.
Regulatory Mechanisms
  - Autonomic Nervous System: Influences heart rate and blood vessel tone via baroreceptors and chemoreceptors.
  - Renin-Angiotensin System (RAS): Contributes to blood pressure regulation through sodium retention and vasoconstriction.
  - Endocrine Hormones: Thyroid and adrenal hormones influence blood pressure, e.g., excess cortisol leads to increased blood pressure.

Age-related changes include:
  - Increased arterial stiffness and calcification.
  - Decreased number of pacemaker cells in the sinoatrial (SA) node.
  - Weakened heart muscle and potential enlargement of the left ventricle, affecting pump efficiency.
  - Reduced sensitivity of baroreceptors, influencing blood pressure regulation.

Smoking: Pack history (smoking quantity and duration).
Lifestyle: Activity vs. sedentary behavior.
Alcohol Consumption: Quantity and frequency.
Health History: Past medical history (previous MIs, hypertension, hyperlipidemia).
Medication History: Current medications and treatments.

New York Heart Association (NYHA) Classes:
- Class I: No limitations in physical activity.
- Class IV: Inability to carry on physical activity without discomfort.

Definition: Percentage of blood ejected from the ventricle with each heartbeat.
Normal EF: Approximately 60%.
Lower EF indicates worsening heart function, particularly in heart failure patients.

Importance of vital signs, particularly blood pressure and heart rate as indicators of perfusion status.
Pulse Assessment Sites:
- Radial, pedal, posterior tibial, popliteal.
Quality of Pulse: Measured on a scale of 0 (absent) to 3 (bounding).
Inspecting Heart Sounds:
  - Auscultation landmarks to identify heart murmurs:
    - Aortic: 2nd intercostal space, right side.
    - Pulmonic: 2nd intercostal space, left side.
    - Tricuspid: 4th intercostal space, left side.
    - Mitral: 5th intercostal space at midclavicular line.

Understanding lipid profiles and normal values for cholesterol and triglycerides.
Low-Density Lipoprotein (LDL): "Bad" cholesterol; elevated levels are concerning.
High-Density Lipoprotein (HDL): "Good" cholesterol; elevated levels are desirable.
Serum Markers:
- Troponin T and I: Indicators of cardiac muscle damage; should be absent in healthy individuals. Elevation suggests ischemia or infarction.
- B-Type Natriuretic Peptide (BNP): Elevated in heart failure.

Definition: Persistent elevation in blood pressure.
- Systolic Hypertension: >140 mmHg.
- Diastolic Hypertension: >90 mmHg.
Types of Hypertension:
- Primary (Essential): Without an identifiable cause; risk factors include age, obesity, smoking, and sedentary lifestyle.
- Secondary: Caused by underlying health issues or medications (e.g., kidney disease).
Hypertensive Crisis:
- Blood pressure >180/120 mmHg; can lead to severe complications and requires emergency intervention.

Lifestyle modifications:
- Regular aerobic exercise (30 minutes, 5 days/week).
- Dietary modifications including the DASH diet to reduce hypertension risk.

First-Line Medications:
- Thiazide diuretics, ACE inhibitors, Angiotensin II receptor blockers (ARBs), calcium channel blockers.
Second-Line Medications: Other diuretics, beta-blockers, and specific renin inhibitors.
Monitoring for medication side effects is crucial, particularly related to electrolyte balance and heart rate.
Important Drug Interactions:
- Grapefruit juice can significantly affect the metabolism of certain cardiovascular medications, leading to increased side effects.

Review pertinent chapters in textbook for more in-depth study.
Focus on understanding concepts related to ejection fraction, functional assessment, interaction of medications, and laboratory markers to better prepare for assessments and patient care in the cardiovascular domain.
Next Session: Atherosclerosis and related conditions.
Break Duration: 5 to 10 minutes before proceeding.