Cardiovascular

Leading Causes of Death in the US

  • Heart Disease: 695,547

  • Cancer: 605,213

  • COVID-19: 416,893

  • Accidents (Unintentional Injuries): 224,935

  • Stroke (Cerebrovascular Diseases): 162,890

  • Chronic Lower Respiratory Diseases: 142,342

  • Alzheimer’s Disease: 119,399

  • Diabetes: 103,294

  • Chronic Liver Disease and Cirrhosis: 56,585

  • Nephritis, Nephrotic Syndrome, and Nephrosis: 54,358
    (CDC, 2021)

Heart Disease Statistics

  • Diabetes Statistics

    • 9.7 million adults have undiagnosed diabetes

    • 29.3 million adults have diagnosed diabetes

    • 115.9 million adults have prediabetes

    • Data based on 2017-2020

  • Cardiovascular Disease (CVD) Statistics (2023 Update)

    • 25.5% of US adults have high Low-Density Lipoprotein Cholesterol (LDL-C) (≥130 mg/dL)

    • Age-adjusted US death rate from CVD: 224.4 per 100,000

    • Age-adjusted global death rate from CVD: 239.8 per 100,000

    • Someone in the US dies from CVD approximately every 34 seconds

    • 2544 US deaths from CVD each day

    • Someone in the US dies from stroke every 3 minutes and 17 seconds

    • 439 US deaths from stroke each day

Cardiac Overview

  • Key Aspects of Heart Functionality

    • Plumbing: Refers to plumbing and sealing functions of the heart

    • Electrical: Conducting electrical impulses for heart rhythm

    • Structural: The structural integrity of the heart

    • Pump Failure: The ability of the heart to pump blood efficiently

Anatomical Structure of the Heart

  • Heart Composition:

    • Four chambers (different wall thickness)

    • Three layers:

    • Endocardium

    • Myocardium

    • Epicardium

  • Pericardium:

    • Composed of visceral and parietal layers

    • Contains pericardial space

  • Wall Thickness:

    • Left ventricular wall is 2 to 3 times thicker than the right

Blood Flow Through the Heart

  • Right Side (Unoxygenated):

    • Blood flows from Superior Vena Cava (SVC) and Inferior Vena Cava (IVC) to right atrium

    • Flows through tricuspid valve to right ventricle

    • Flows through pulmonic valve to pulmonary artery to lungs

  • Left Side (Oxygenated):

    • Blood flows from pulmonary veins to left atrium

    • Flows through mitral valve to left ventricle

    • Flows through aortic valve to systemic circulation

Heart Valves

  • Types of Heart Valves:

    • Mitral Valve

    • Tricuspid Valve

    • Pulmonic Valve

    • Aortic Valve

    • Chordae Tendineae

    • Papillary Muscle

Coronary Circulation

  • Coronary Arteries:

    • Major coronary arteries include the left and right coronary arteries

    • Left Coronary Artery:

    • Branches into Left Anterior Descending and Left Circumflex

    • Supplies blood to left atrium, left ventricle, interventricular septum, part of right ventricle

    • Right Coronary Artery:

    • Supplies blood to right atrium, right ventricle, part of posterior left ventricle

    • Includes AV node and bundle of His

    • Coronary Veins:

    • Drain into coronary sinus

Conduction System

  • Specialized tissue creates and transports electrical impulses leading to heart muscle contraction (depolarization)

  • Process: Begins at Sinoatrial (SA) node → Interatrial pathways → Atrial contraction → Atrioventricular (AV) node → Internodal pathways → Bundle of His → Left and right bundle branches → Purkinje fibers → Ventricular contraction

Electrocardiogram (ECG)

  • Records electrical activity of heart using P, QRS, T, and U waveforms

  • P Wave: Firing of SA node and depolarization of atria

  • QRS Complex: Depolarization from AV node throughout ventricles

  • T Wave: Repolarization of ventricles

  • U Wave (if seen): Repolarization of Purkinje fibers (may signify hypokalemia)

  • Intervals: PR, QRS, QT intervals measure signal travel time across different heart areas

Heart Functionality Terms

  • Systole: Contraction of heart muscle; ejection of blood from ventricles

  • Diastole: Relaxation of heart muscle; ventricles fill with blood

  • Stroke Volume (SV): Amount of blood ejected with each heartbeat

  • Cardiac Output (CO): Amount of blood pumped by each ventricle in one minute; defined by: CO = SV imes HR

    • Normal ranges: 4 to 8 L/min

Factors Affecting Cardiac Output

  • Preload: Volume of blood stretching the ventricles at the end of diastole

    • Frank-Starling Law: Increased stretch leads to increased force of contraction

    • Conditions affecting it: Hypertension (HTN), aortic valve disease, hypervolemia

  • Contractility:

    • Increased by epinephrine and norepinephrine from the Sympathetic Nervous System (SNS)

    • Increased contractility leads to increased SV through enhanced ventricular emptying

  • Afterload: Peripheral resistance against which the left ventricle must pump

    • Dependent on ventricle size, wall tension, and blood pressure

    • Increased BP results in increased resistance and workload leading to hypertrophy

Cardiac Reserve

  • The ability of the cardiovascular system to maintain or increase cardiac output in response to various health situations such as exercise, stress, or hypovolemia

Regulatory Mechanisms of the Cardiovascular System

  • Autonomic Nervous System (ANS) Effects on Heart:

    • Sympathetic Stimulation: Increases HR, impulse speed through AV node, and force of contractions; mediated through (\beta)-adrenergic receptors

    • Parasympathetic Stimulation: Decreases HR and impulse conduction from SA to AV node; mediated by vagus nerve

  • Effect on Blood Vessels:

    • Sympathetic stimulation of (\alpha)-adrenergic receptors causes vasoconstriction; decreased stimulation results in vasodilation

Regulation by Baroreceptors

  • Located in the aortic arch and carotid sinus, these are sensitive to arterial pressure/stretch

    • Stimulation inhibits SNS and enhances PNS leading to decreased HR and peripheral vasodilation; opposite occurs with decreased stretch or pressure

  • Chemoreceptors: Located in aortic and carotid bodies, changes in CO2 levels lead to alterations in respiratory rate and blood pressure

Blood Pressure

  • Blood Pressure Definition: Force exerted by blood against arterial walls

  • Systolic Blood Pressure (SBP): Peak pressure during ventricular contraction; normal defined as less than 120 mm Hg

  • Diastolic Blood Pressure (DBP): Residual pressure during relaxation; normal defined as less than 80 mm Hg

  • Factors Influencing Blood Pressure:

    • Cardiac Output (CO) and Systemic Vascular Resistance (SVR)

    • Relationship expressed as:
      BP = CO \times SVR

Measurement of Blood Pressure

  • Invasive Technique: Catheter inserted into an artery attached to a transducer

  • Noninvasive Techniques:

    • Sphygmomanometer and stethoscope; measure as SBP/DBP

    • Use correct cuff size and positioning; brachial artery is recommended site

    • First Korotkoff phase equals SBP (first sound); Fifth Korotkoff phase equals DBP (sound disappears)

    • Automated device; Doppler ultrasonic flowmeter can also be used

Pulse Pressure and Mean Arterial Pressure

  • Pulse Pressure:

    • Difference between SBP and DBP; normally about 1/3 of SBP

    • Increased with exercise, atherosclerosis; decreased with heart failure, hypovolemia

  • Mean Arterial Pressure (MAP):

    • Average pressure within the arterial system; calculated as:
      MAP = \frac{(SBP + 2 \times DBP)}{3}

    • MAP must be greater than 60 mm Hg to perfuse vital organs to avoid ischemia

Gerontologic Considerations

  • The risk of cardiovascular disease (CVD) increases with age

  • Coronary artery disease (CAD) due to atherosclerosis; most common problem observed

  • CVD is a leading cause of death in adults over age 65

  • Cardiovascular changes result from aging, disease, environmental factors, and lifetime health behaviors

Subjective Data Collection

  • Medical Comorbidities:

    • Hypertension, Hyperlipidemia, Diabetes, Sleep Apnea, Kidney disease, Coagulopathies

  • Family History:

    • Coronary disease (early onset), Long QT syndrome, Congenital/inheritable abnormalities, Sudden Cardiac Death, Stroke

Genetic Links Related to Heart Conditions

  • Coronary Artery Disease: Linked to lipoprotein genes

  • Cardiomyopathy: Autosomal and X-linked dominant mutations

  • Hypertension: Influenced by genetic, environmental, and lifestyle factors

Risk Factor Identification

  • Modifiable Risk Factors:

    • Blood Pressure, Smoking, Cholesterol levels, Diabetes, Physical inactivity, Obesity

  • Non-Modifiable Risk Factors:

    • Age, Gender, Family History, Race

Objective Data Collection

  • Physical Assessment:

    • Assess general appearance and vital signs

    • Measure manual BP bilaterally; assess postural BP and HR

Assessment of Peripheral Vascular System

  • Inspection:

    • Skin color, hair distribution, venous pattern, edema, clubbing, lesions

    • Jugular venous distention (JVD) indicates right-sided heart failure

  • Palpation:

    • Temperature, moisture, and edema assessment

    • Palpate pulses for rhythm and force (0 to 3+); assess for thrills

    • Assess capillary refill in less than 2 seconds

Documentation of Palpation Pulses

  • Pulse Documentation:

    • 3+ Bounding

    • 2+ Normal

    • 1+ Weak

    • 0 Absent

  • Peripheral Edema Documentation:

    • 1+ Mild pitting with slight indentation; no appreciable extremity edema

    • 2+ Moderate pitting; thumb indentation resolves rapidly

    • 3+ Deep pitting; indentation remains briefly with observable edema

    • 4+ Severe pitting; indentation persists; visibly swollen extremity

Anatomical Landmarks for Cardiovascular Assessment

  • Common Anatomical Landmarks:

    • 2nd rib, Midsternal Line (MSL), Midclavicular Line (MCL), Anterior Axillary Line (AAL)

    • Angle of Louis related to major valves

Physical Examination of the Cardiovascular System

  • Thorax: Inspection and palpation

  • Auscultation Areas:

    • Aortic, Pulmonic, Tricuspid, Mitral, Erb’s point

    • Evaluate for abnormal pulsations or thrills

    • Inspect the epigastric area for abdominal aorta pulsation

    • Examining for heaves and Point of Maximal Impulse (PMI)

Heart Sounds Auscultation

  • S1: Closure of mitral and tricuspid valves; “Lubb”; beginning of systole

  • S2: Closure of aortic and pulmonic valves; “Dubb”; beginning of diastole

  • Use diaphragm for better clarity; note any pulse deficit during auscultation

Extra Heart Sounds

  • S3: Ventricular gallop; heard in early diastole; indicates fluid overload; low-pitched

  • S4: Atrial gallop; occurs in late diastole; refers to a “stiff” wall; low-pitched

Heart Murmurs

  • Innocent murmur: Low-pitched in children, may be musical and best heard at left lower sternal border.

  • Systolic Murmurs: E.g., Aortic Stenosis and Mitral Regurgitation; best heard at the respective valve area with specific characteristics.

  • Diastolic Murmurs: E.g., Aortic Regurgitation; best practices for detection include positioning and diaphragm use.

Electrocardiogram Diagnostic Studies

  • Types of ECG:

    • Resting 12 lead ECG

    • Ambulatory ECG monitoring (Holter)

    • Exercise or stress testing

    • Event monitor or loop recorder

    • Internal monitoring for serious dysrhythmias

Arrhythmias

  • Types of Arrhythmias: E.g., atrial flutter

Functional Studies

  • Include exercise stress testing to determine oxygen demand

Imaging Techniques

  • Chest X-ray: Checks for displacement, pericardial effusion, and pulmonary congestion

  • Echocardiogram: Uses ultrasound waves to assess heart structure and function, including ejection fraction (EF)

Interventional Studies

  • Cardiac Catheterization: Evaluates coronary artery disease through visual diagnostics and interventions

Cardiac Disease Processes Overview

  • Including Hypertension, Coronary Artery Disease, and Heart Failure

Hypertension

  • Prevalence: Affects ~45% of adults in the US

  • Contributes to ~23.7% of heart disease deaths

  • Many people require a combination of medication and lifestyle adjustments

    • 108 million US adults with hypertension, 71% not controlled, 49% untreated

Classification and Risks of Hypertension

  • Classification table of BP readings

  • Risk factors and lifestyle correlation: Age, Sex, Race, Education level

Hypertension Effects

  • Increases risk for complications such as myocardial infarction (MI) and heart failure

Clinical Manifestations of Hypertension

  • Symptoms of Hypertension: Fatigue, Dizziness, Palpitations, Angina, Dyspnea

Management Strategies for Hypertension

  • Lifestyle modifications based on AHA guidelines for controlling blood pressure

  • Educational approaches for promoting adherence

Nursing Management for Hypertension

  • Assessment Considerations: Subjective and objective data collection to assess cardiovascular status

    • Health management education on lifestyle improvements and pharmacologic therapy adherence

    • Monitoring & patient support through clinic visits

Nursing Evaluation for Hypertension Management

  • Expected outcomes include achieving individualized BP goals and reporting minimal side effects from therapy.

Case Studies Overview

  • Included for practical assessment and application of hypertension knowledge in patient scenarios regarding risk factors for CAD and therapeutic interventions needed.

Guidelines on Cardiac Disease Management

  • Comprehensive criteria for assessing cardiac events such as myocardial infarction and acute coronary syndrome

Final Notes

  • Discussion on complications related to acute coronary syndromes and heart failure, emphasizing nursing assessments and patient management strategies in real-world applications.

Conclusion

  • Importance of understanding the integrative nature of cardiovascular health, risk factors, and comprehensive assessments in professional nursing practice to promote patient outcomes.