Cardiovascular System

Assessment of the Cardiovascular System

Overview

  • Chapter 27 of Medical-Surgical Nursing by Professor Ogle (Spring 2026)

Learning Outcomes

  • Utilize knowledge of anatomy and physiology to perform focused assessments of the cardiovascular system.

  • Demonstrate clinical judgment in interpreting assessment findings in patients with cardiovascular conditions.

  • Plan evidence-based care for patients with cardiovascular conditions that necessitate diagnostic testing.

Anatomy Review

Goals

  • The primary goal is to supply oxygen to organs and tissues, termed perfusion.

Inner structures of the heart

  • Atria:
      - Left atrium
      - Right atrium

  • Ventricles:
      - Left ventricle
      - Right ventricle

  • Valves:
      - Aortic valve
      - Mitral valve
      - Tricuspid valve
      - Pulmonic valve

Layers of the Heart

  • Endocardium

  • Myocardium

  • Epicardium

  • Pericardium
      - Visceral pericardium
      - Pericardial space
      - Parietal pericardium

Outer Structures of the Heart

  • Coronary arteries

  • Superior vena cava

  • Inferior vena cava

  • Aorta

  • Pulmonary arteries

Cardiovascular System Overview

Components of the Cardiovascular System

  • The cardiovascular system is composed of the heart, arteries, arterioles, capillaries, venules, and veins.

  • Collaborates with the:
      - Respiratory system
      - Hematologic system

Compensation Mechanisms

  • Problems with these systems lead to cardiovascular system compensations:
      - Increased heart rate (HR)
      - Increased blood pressure (BP)

Cardiovascular Anatomy & Physiology Terms

Cardiac Output (CO)

  • Definition: The amount of blood pumped from the left ventricle each minute.

  • Equation: CO=HRimesSVCO = HR imes SV
      - HR (Heart Rate): The number of beats per minute.
      - SV (Stroke Volume): The amount of blood ejected by the left ventricle during each contraction (systole).     - Influenced by:
          - Heart Rate
          - Preload
          - Afterload
          - Contractility
            - Preload: The degree of ventricular stretch before contraction; excessive preload can negatively impact cardiac output.
            - Afterload: The resistance the ventricle must overcome to eject blood (related to blood pressure).
            - Contractility: The effectiveness of the myocardium's contraction, negatively affected by conditions like hypoxia and acidemia.

Arterial System

Blood Pressure

  • Definition: The force of blood exerted against vessel walls.

  • Required components:
      - Volume
      - Pump
      - Vascular tone

Regulating Mechanisms

  • Autonomic Nervous System (ANS):
      - Composed of sympathetic and parasympathetic nervous systems.

  • Endocrine System:
      - Activates ANS through substances like catecholamines, kinins, serotonin, and histamines.
      - Renin-Angiotensin-Aldosterone System (RAAS): Involvement of the kidneys in blood pressure regulation.

  • Blood Pressure Indicators:
      - Systolic BP: Indicator of ventricular function and vascular tone.
      - Diastolic BP: Pressure against arterial walls during ventricular diastole.

Sensory Receptors

  • Baroreceptors:
      - React to stretching; when stretched due to increased BP, they block the vasomotor center to lower BP.
      - Decreased volume or pressure sends fewer signals to the CNS, which activates the sympathetic nervous system, increasing HR and BP.

  • Chemoreceptors:
      - React to hypoxemia; when oxygen in arterial blood decreases, they activate the vagus nerve to increase BP.

Venous System

Objectives

  • Main goal: Complete blood circulation by returning blood from capillaries to the right side of the heart.

  • Features:
      - Typically has less vascular tone, making it more accommodating to changes in fluid volume.
      - Most veins possess valves to prevent backward flow.

Cardiovascular Assessment

Patient History

Nonmodifiable Risk Factors

  • Age

  • Gender

  • Ethnicity

  • Family history of cardiovascular disease (CVD).

Modifiable Risk Factors

  • Cigarette smoking

  • Sedentary lifestyle

  • Obesity

  • Diet

  • Psychological factors

  • Illicit drug use

  • Alcohol use

Social History

  • Aspects to consider:
      - Living situation (alone or with others)
      - Environment
      - Occupation
      - Support systems

5A Approach for Smoking Cessation

  1. Ask about tobacco use.

  2. Advise patients to quit.

  3. Assess readiness to quit.

  4. Assist by providing resources.

  5. Arrange follow-up.

History of Present Illness (HPI)

  • Comprehensive assessment of concerns, including:
      - Onset
      - Duration
      - Sequence
      - Frequency
      - Location
      - Quality
      - Intensity
      - Associated symptoms
      - Precipitating, alleviating, and aggravating factors

Symptoms

  • Pain/Discomfort:
      - Distinguishing between cardiac and noncardiac pain (Refer to Table 27.1, p. 645)
      - Women may experience discomfort often resembling indigestion rather than chest pain.

  • Dyspnea:
      - Includes dyspnea on exertion (DOE), orthopnea, and paroxysmal nocturnal dyspnea (PND).

  • Fatigue:
      - A nonspecific symptom often associated with decreased cardiac output (CO).

  • Palpitations:
      - A subjective sensation of fluttering in the chest, often related to irregular heart rhythms.

Other Indicators

  • Weight Gain:
      - An early indicator of positive fluid balance leading to edema.

  • Syncope:
      - A brief loss of consciousness due to decreased cerebral blood flow, often linked with reduced CO.

  • Near-Syncope:
      - Dizziness with an inability to remain upright.

  • Extremity Pain:
      - Can stem from ischemia (from atherosclerosis) or venous insufficiency.
      - Intermittent Claudication:
      - Pain related to decreased arterial tissue perfusion.

Physical Assessment Components

Signs & Symptoms of Cardiovascular Alterations

  • Skin Changes:
      - Cool, pale, moist skin.
      - Central cyanosis noticeable at nail beds, earlobes, lips, toes.
      - Peripheral cyanosis.

  • Extremities:
      - Clubbing of fingers indicative of chronic hypoxia (increased nail bed angle).
      - Peripheral edema.

  • Blood Pressure:
      - Hypertension defined as BP ≥ 140/90 mmHg.
      - Hypotension defined as BP ≤ 90/60 mmHg.
      - Orthostatic hypotension.
      - Ankle-brachial index assessment.

Peripheral Blood Flow

  • Jugular Venous Distension (JVD):
      - Assess central vs. peripheral arterial pulses.

  • Bruits:
      - Indicate turbulent blood flow due to arterial narrowing.

  • Precordium Inspection:
      - Inspect for prominent pulses.
      - Auscultate for abnormal heart sounds, including gallops and murmurs (S₃ & S₄); listen for pericardial friction rub.

  • Psychosocial Assessment:
      - Evaluate psychological defense mechanisms (e.g., denial) and support systems.

Cardiovascular Diagnostic Assessments

Laboratory Tests

  • Troponin Levels:
      - Troponin is a myocardial muscle protein released due to myocardial injury.

  • Lipids:
      - Total cholesterol should be < 200 mg/dL.   - Triglycerides vary slightly between genders; ideal levels are 40-160 mg/dL.   - High-density lipoproteins (HDL) should be > 45 mg/dL.
      - Low-density lipoproteins (LDL) should be < 130 mg/dL.

Blood Coagulation Studies

  • Assessments include:
      - Prothrombin time (PT)
      - International normalized ratio (INR)
      - Partial thromboplastin time (PTT)
      - These tests are critical in managing anticoagulation therapy.

Erythrocytes (RBCs)

  • Increased levels may occur in cardiovascular diseases due to compensation for decreased oxygen availability.

Electrolyte Balance

  • Hyperkalemia:
      - Characterized by peaked T waves.

  • Hypocalcemia:
      - Can lead to ventricular dysrhythmias, prolonged QT interval, and cardiac arrest.

  • Hypomagnesemia:
      - Associated with torsades de pointes and prolonged QT interval.

Imaging Tests

  • Chest X-Ray:
      - Used to evaluate the size, silhouette, and position of the heart.
      - Can indicate cardiac enlargement, pulmonary congestion, cardiovascular calcifications, and verify central line placement.

Invasive Testing

  • Cardiac Catheterization:
      - Most definitive diagnostic test for heart disease, invasive in nature.
      - Important pre-requisites:
        - Assess patient’s physical and psychological readiness.
        - Verify signed informed consent.
        - NPO status: 6 hours for solids; 2 hours for fluids.
        - Baseline assessment including vital signs.
        - Prepare the procedure insertion site (radial vs. femoral).
      - Several procedures can be performed by a cardiologist.
      - Post-operative care focuses on keeping the procedure extremity straight (2-6 hours depending on site) and vascular checks along with vital signs.
      - Provide appropriate discharge education.

Electrocardiography (ECG)

  • Types:
      - Resting ECG
      - Holter monitoring
      - Exercise electrocardiography (stress test)
        - Requires signed informed consent and immediate availability of necessary equipment (cardiac drugs, defibrillator).
        - Monitor for symptoms post-test that may necessitate admission.

  • Electrophysiology Study (EPS):
      - Involves electrical stimulation to provoke lethal dysrhythmias for evaluation purposes.

Echocardiography

  • Definition: An ultrasound of the heart used to assess structure and mobility.

  • Evaluates factors such as chamber sizes, ejection fraction, and flow gradient across valves.

  • Transesophageal Echocardiography (TEE):
      - Utilizes an ultrasound transducer placed behind the heart in the esophagus for examining cardiac structure and function.

Imaging Techniques

  • CT Imaging:
      - Coronary Artery Calcium (CAC) Calculation: Identifies patients at risk for coronary artery disease (CAD).
      - CT Angiography (CTA): Involves IV contrast to identify areas of stenosis.

  • MRI:
      - Provides detailed images measuring cardiac wall thickness, chamber dilation, valve function, and blood movement in the major vessels.
      - Note on patient safety: Considerations are necessary for patients with pacemakers.