Cardio part 2 Adult Health

12-Lead Electrocardiogram (EKG/ECG)

• Measures the electrical activity of the heart from twelve different angles
• Standard diagnostic tool for cardiac assessment
• Interpreted by trained professionals like cardiologists and doctors
• Electrodes placed on limbs and chest to view the heart from different directions
• Left arm electrodes look down at the heart
• Right arm electrodes look diagonally toward the heart
• V leads look from below the heart
• Leg leads provide additional perspectives
• PQRST waveforms appear differently in different leads due to varying perspectives

Telemetry Monitoring

• Continuous cardiac monitoring system used primarily in hospital settings
• Real-time observation of a patient's heart activity at a central monitoring station
• Provides continuous monitoring of heart activity
• Monitored at the nurse's station, with alarms to alert staff to issues
• Three-Lead System uses white, black, and red leads
• White lead is placed on the right side of the chest
• Red lead is placed on the left side, just under the ribs
• Black lead is placed opposite the white lead
• Mnemonic: "White on right, red on ribs, black opposite white," alternatively "Smoke over fire" (black over red)
• Five-Lead System expands on the three-lead system with additional leads
• White lead: Right side of the chest, just under the clavicle
• Green lead: Below the ribs
• Black lead: Smoke (over fire)
• Red lead: Fire
• Brown lead: Near the heart
• Mnemonic: "Clouds over grass, smoke over fire, brown by the heart."

Holter Monitor

• Portable device used to continuously record the heart's electrical activity over an extended period
• Detects intermittent arrhythmias or palpitations not evident during a brief office visit
• Used for patients experiencing intermittent palpitations or arrhythmias
• Monitoring period can vary (12 hours to 10 days), depending on symptom frequency
• Patients wear the monitor while going about their daily lives
• After monitoring, the device is returned to the doctor's office for data download and analysis
• Electrode placement is similar to telemetry, but specific placement is crucial for accurate readings
• White lead: Right side
• Black lead: Opposite the white lead
• Red lead: Smoke over fire
• Green lead: Clouds over grass
• Brown lead: By the heart

Hemodynamic Monitoring

• Involves invasive techniques used in critical care settings to assess a patient's circulatory function
• Provides continuous data on parameters like blood pressure and cardiac output
• Primarily used in critical care units
• Typically managed by registered nurses (RNs)
• Unstable hemodynamics refers to unstable vital signs
• Arterial pressure catheter inserted into a wrist artery to continuously measure systolic blood pressure
• Includes central venous monitoring, pulmonary artery wedge pressure

Stress Test

• Evaluates the heart's function under physical exertion or pharmacological stimulation
• Determines if the heart receives enough blood and oxygen during stress
• Methods include exercise stress test and pharmacological stress test
• Exercise stress test is typically performed on a treadmill or stair climber
• Patients wear a monitor and blood pressure cuff
• Starts with walking and progresses to running
• Requires comfortable clothing and tennis shoes
• Monitors heart response to increasing stress
• Performed until the limit of exertion
• Evaluates for myocardial dysrhythmias, cardiac capability, and ischemia
• Pharmacological stress test uses medication to simulate the effects of exercise on the heart
• Medications include adenosine (Adenocard) and dipyridamole (Persantine)
• Adenosine is the most popular choice
• Thallium scan uses a radioactive isotope (thallium) to assess blood flow to the heart during exercise or with adenosine
• Performed with exercise or adenosine
• Purpose to stress the heart and observe its response

Echocardiogram

• Ultrasound of the heart
• Non-invasive imaging technique used to assess the heart's structure and function

Ventricular Ejection Fraction (EF)

• Measures the percentage of blood pumped out of the left ventricle with each contraction
• Normal EF is generally 55% to 70%, but may vary slightly between facilities
• Target EF: Aim for greater than 60%
• Moderate Heart Failure: EF between 40% and 55%
• Moderate to Severe Heart Failure: EF less than 40%
• Significance: EF indicates how efficiently the heart is pumping blood

Chest X-Ray

• Standard radiographic image of the chest
• Used in cardiology to assess the size and shape of the heart
• Purpose: Evaluates the size and shape of the heart
• Limitations: Primarily focuses on cardiac aspects, not lung infiltrates

Angiography and Cardiac Catheterization

• Angiography involves visualizing blood circulation using dye injection
• Cardiac catheterization is a specific type of angiography focused on the heart's coronary arteries
• Angiography is a general term for imaging blood vessels with dye
• Cardiac catheterization specifically examines the coronary arteries of the heart
• Procedure involves passing a catheter through a peripheral vessel (artery) to reach the heart
• Access points include the radial artery (newer, less invasive) and the femoral artery (traditional)
• Performed in a surgical suite
• Requires informed consent from the patient
• Uses iodine-based contrast dye
• Allergy check is essential due to iodine content
• Post-procedure care includes:
• Distal assessment: Check pulses, color, and sensation of the distal extremity to ensure adequate blood flow
• Frequency of checks: Every 15 minutes for the first hour, then every 30 minutes for the next hour, then hourly for four hours (or per facility protocol)
• Pressure dressing: Apply a pressure dressing to the puncture site to prevent bleeding
• Dressing management: Never remove the pressure dressing
• Bleeding check: Monitor for blood seeping under the patient
• Vital signs: Monitor vital signs regularly
• Positioning: Patient must lay supine to avoid opening the artery

MUGA Scan

• (Multiple Gated Acquisition) scan uses a radioactive tracer and a camera to take pictures of the heart as it pumps
• Radioactive tracer is injected, and a camera captures images of the heart during pumping
• Images are taken at rest and during exercise to assess heart function under stress
• Patient preparation:
• NPO (nothing by mouth) for six hours prior to the scan
• No caffeine or tobacco before the test
• Post-procedure: Force fluids to help eliminate the radioactive tracer

Coronary Artery Calcium Score

• Diagnostic test that visualizes plaque deposits in the coronary arteries to assess the risk of coronary artery disease
• Purpose to visualize plaque deposits containing calcium in the coronary arteries
• Plaque Identification is used to detect calcium in plaque, indicating potential risk for heart attack
• Determines the patient's risk of coronary artery disease
• Score interpretation:
• Zero means no evidence of heart disease
• 10-300 means moderate evidence of heart disease
• Greater than 300 means high chance of severe heart disease

EKG Basics

• (Electrocardiogram, ECG) records the electrical activity of the heart over time
• Voltage is represented by the height of the waveform on the EKG paper
• Time is represented horizontally on the EKG paper
• Small Box Measurement: Each small box on the EKG paper represents 0.04 seconds
• Large Box Measurement: Five small boxes equal 0.20 seconds (0.04 x 5 = 0.20)

EKG Waveform Components

• Understanding the different waves and intervals on an EKG is crucial for interpreting cardiac function
• P Wave: Represents atrial contraction (depolarization)
• Should be an upward wave in lead II
• There should be one P wave for every QRS complex
• P waves should be similar in shape and size
• QRS Complex: Represents ventricular contraction (depolarization)
• Q is the first downward deflection
• R is the upward deflection
• S is the downward deflection following the R wave
• T Wave: Represents ventricular repolarization (resetting)
• PR Interval: Represents atrioventricular (AV) conduction time
• Normal Range: 0.12 to 0.20 seconds
• Measured from the beginning of the P wave to the start of the QRS complex
• QRS Interval: Represents the time it takes for ventricular depolarization
• Normal Range: 0.06 to 0.08 seconds
• ST Segment: Represents the period between ventricular depolarization and repolarization
• Should be near the baseline
• ST Elevation: If the ST segment is elevated above the baseline, it may indicate a heart attack (myocardial infarction)

EKG Graph Paper Measurements

• Understanding the measurements on EKG graph paper is essential for accurate interpretation
• Small box width is 0.04 seconds
• Large box width is 0.20 seconds (5 small boxes x 0.04 seconds/box)
• Key Terms and Important Points include:
• P Wave: Represents atrial depolarization (atrial contraction)
• PR Interval: Represents the time between atrial and ventricular depolarization
• QRS Complex: Represents ventricular depolarization (ventricular contraction)
• T Wave: Represents ventricular repolarization
• Rhythm: Should be regular in a normal heart
• Normal Heart Rate: 60-100 beats per minute

Sinus Arrhythmias

• Originate from the sinoatrial (SA) node and are characterized by variations in heart rate often related to breathing patterns
• Sinus Arrythmia is a normal finding where the regularity of the heart rhythm is slightly altered during inspiration
• Regularity: The heart rhythm varies slightly with breathing
• Prevalence: Common and healthy in young people
• Treatment: Usually requires no treatment as it doesn't typically cause symptoms or problems

Sinus Bradycardia

• Slow heart rate originating from the SA node
• Bradycardia is defined as a heart rate below 60 bpm
• Definition: Heart rate less than 60 bpm
• ECG Characteristics: Everything else on the ECG (P wave, QRS complex, T wave) looks normal; only the rate is slow
• Causes:
  • SA Node Defects are issues with the heart's natural pacemaker
  • Myocardial Infarction (MI) can damage the SA node
  • Ischemic Drugs like beta blockers and calcium channel blockers decrease heart rate
  • Digoxin Toxicity can cause bradycardia, hold if heart rate is less than 60 bpm
  • Sleep Apnea can lead to a slower heart rate
  • Vagal Stimulation can drop heart rate
• Symptoms depend on how low the heart rate is:
  • Chest pain
  • Shortness of breath
  • Confusion
  • Syncope (fainting)
  • Hypotension (low blood pressure)

Sinus Tachycardia

• Rapid heart rate originating from the SA node
• Considered a heart rate greater than 100 bpm
• Definition: Heart rate greater than 100 bpm
• Rate: Usually between 100-150 bpm, but can be higher
• ECG Characteristics: All complexes are normal; the rhythm is regular, but fast
• Physiological Response is a response to the body's need for increased cardiac output
• Causes:
  • Exercise, fever, anxiety, hypovolemia, and various medications can stimulate an increased heart rate
• Symptoms depend on the heart rate
  • Palpitations
  • Chest pain
  • Shortness of breath
  • Decreased level of consciousness
  • Confusion
  • Syncope
  • Dizziness
  • Hypotension
  • Severe Tachycardia can trigger chest pain and ischemia, indicating underlying cardiac disease

Atrial Arrhythmias: Atrial Fibrillation (A-Fib)

• Common atrial arrhythmia characterized by rapid, chaotic electrical activity in the atria, leading to an irregular heart rhythm
• Chaotic atrial rhythm with a rapid atrial rate
• Atrial Rate typically between 350-600 beats per minute (atrial rate, not ventricular)
• The atria are fibrillating (quivering) instead of pumping effectively
• ECG Characteristics:
  • Absence of distinct P waves due to the chaotic atrial activity
  • Irregularly irregular rhythm -QRS complexes are present but may not be as fast as the atrial rate
• Ensure the patient is still during ECG recording to avoid mistaking movement for fibrillation

ECG Rhythm Analysis Techniques

• Analyzing ECG rhythms requires a systematic approach
• Calipers or Paper Method is used to measure the R-R intervals
  • Mark the R waves on the paper and compare the intervals across the rhythm strip
  • Variations in R-R intervals indicate irregularity
  • Six-Second Strip Method: If the ECG strip is six seconds long, count the number of QRS complexes
  • Multiply the number of complexes by 10 to estimate the heart rate Example: 5 complexes in a 6-second strip ≈ 50 bpm
  • Three-Second Markers: ECG paper often has markers indicating 3-second intervals. Two markers represent 6 seconds, aiding in quick heart rate estimation

Atrial Fibrillation (Cardiac Arrythmias Comprehensive Study Guide)

• Characterized by a chaotic atrial rhythm and an irregular ventricular rhythm, leading to an irregular pulse
• The hallmark of atrial fibrillation is its irregularity
• The ventricular rate (heart rate) can range from 50 to 180 beats per minute, distress is indicated at a rate of 180
• Expect an irregular radial and apical pulse
• Causes:
  • Heart failure (HF), previously referred to as congestive heart failure (CHF)
  • Atrial hypertension
  • Can be transient in healthy individuals
  • Complications: Quivering atria can lead to clot formation, increasing the risk of stroke, pulmonary embolism, and heart attack
• Treatment:
  • Medications to convert back to sinus rhythm for asymptomatic patients
  • Cardioversion (electrical or chemical) electrical cardioversion involves delivering a controlled shock, though less intense than for ventricular rhythms. Chemical cardioversion uses medications for symptomatic patients

Atrioventricular (AV) Blocks

• Involved in a defect in the AV junction, impairing the conduction of impulses from the SA node (pacemaker) to the ventricles
• The block occurs somewhere between the SA node and the AV junction
• Degrees of AV Block:
  • First-Degree AV Block is usually asymptomatic and has a prolonged PR interval
  • Second-Degree AV Block may cause vertigo or weakness
  • Third-Degree AV Block (Complete Heart Block): - Atria and ventricles beat independently (not coordinated) - Has serious condition requiring immediate intervention - Causes low blood pressure, low heart rate (e.g., 30s or lower), and chest pain - Treatment involves a pacemaker

Premature Ventricular Contractions (PVCs)

• Premature contractions originate outside the SA node, often in the Purkinje fibers
  • Origin: Ectopic focus in the ventricles, not the SA node
  • Subjective Experience: Often felt as a "skipped beat."
  • Causes: Stress, emotional upset, hypoxemia, or can occur spontaneously
  • ECG Characteristics:
    • Absent P wave preceding the QRS complex
    • Wide QRS complex (greater than 0.06-0.08 seconds)
    • T wave is opposite in direction to the QRS complex
    • Compensatory pause after the PVC where a radial pulse may not be felt
  • Treatment:
  • Antiarrhythmic drugs (e.g., lidocaine, procainamide) for frequent PVCs
  • Clinical Significance:
    • Uniform PVCs, frequent PVCs, multiform PVCs
    • Patterns: Bigeminy every other beat is a PVC, Trigeminy every third beat is a PVC

Ventricular Tachycardia (V-tach)

• Life-threatening arrhythmia characterized by a rapid ventricular rate of over 100 bpm
• Rate: Ventricular rate exceeds 100 bpm. ECG Characteristics: Absent P waves, wide and often notched QRS complexes, and buried T wave
• Hemodynamic Effects: Decreased cardiac output
• Causes: Digoxin toxicity, low potassium or magnesium, heart disease, and hypoxia
• Clinical Action: "Oh crap" moment requires immediate assessment and intervention
• Check for a pulse; pulseless V-tach leads to cardiac arrest
• Treatment:
• Antiarrhythmic drugs, and defibrillation

Ventricular Fibrillation (V-fib)

• Life-threatening arrhythmia where the ventricles quiver instead of pumping
• Results in no cardiac output
• Ventricular Activity means that the ventricles are quivering, not contracting effectively
• Causes no cardiac output and cardiac arrest
• Clinical Status: Cardiac arrest, no pulse
• ECG Characteristics: Chaotic, wavy line with no identifiable complexes
• Causes: Myocardial infarction (MI) or heart attack, coronary artery disease, cardiomyopathy, hypothermia, digoxin or quinidine toxicity, electrolyte imbalances (e.g., hyperkalemia, low magnesium, low potassium), and electrical shock
• Treatment: CPR, electrical defibrillation, and ACLS drugs (administered during a code)
• Asystole occurs when there is no electrical activity in the heart
• Prognosis is generally poor

Asystole

• Absence of electrical activity in the heart
• There is no heartbeat, no blood pressure
• Prognosis is generally poor, but recovery is possible in some cases
• Possible Causes: Hypoxia (lack of oxygen), acidosis (excessive acid in the body fluids), potassium imbalance (either high or low), drug overdose, and hypothermia (abnormally low body temperature)
• Treatment: CPR (Cardiopulmonary Resuscitation), Epinephrine (Adrenaline), Atropine, and cardiac pacing (in specific circumstances)
• Cardiac Pacing Limitations: Requires some electrical activity to be effective. Defibrillation Ineffectiveness: Defibrillation is not effective in asystole because there is no electrical activity to shock

Defibrillation Key Considerations

• Defibrillation is a procedure used to treat life-threatening conditions affecting the heart's rhythm
• Delivers an electrical shock to the heart to restore a normal heartbeat
• Must follow specific guidelines and safety measures to ensure the procedure's effectiveness and prevent harm to both the patient and medical personnel
• CPR must be performed on a hard surface to be effective
• Ensure the area is dry; avoid standing in water during defibrillation. Ensure everyone is clear of the patient before delivering the shock
• Use gel or conductive pads between the patient's skin and the paddles to ensure good electrical contact
• Apply pads in a specific configuration to direct electricity through the heart
• A cardiac rhythm must be present before defibrillation can be performed
  • Defibrillation is not used in asystole (flatline)
• Procedure protocol states:
  • CPR and medications are administered between shocks
  • Do not administer shocks continuously without assessing the patient's condition.
  • After a shock, check for a heartbeat
  • If there is no heartbeat, resume CPR and administer medications while the defibrillator recharges
• Paddles are placed at the apex of the heart and on the right side of the upper sternum
• Before delivering a shock, announce "Clear" to ensure everyone is away from the patient
• Document the number of defibrillations, energy levels (e.g., 200, 300, 360 joules), and the patient's condition after each shock -Scope of Practice: LPNs (Licensed Practical Nurses) typically do not perform defibrillation or administer IV push medications

Cardioversion vs Defibrillation

• Both procedures deliver electrical shocks to the heart but are used in different clinical scenarios
• Defibrillation is used in cardiac arrest situations, while cardioversion is used when the patient has a heartbeat but needs to have their heart rhythm corrected

Pacemakers

• Medical device used to help regulate the heart rate when the heart's natural pacemaker is not functioning correctly
• Typically used when the heart rate is too slow, such as in cases of sinus bradycardia or other bradycardias
• Used when the heart rate is too low (e.g., sinus bradycardia) and only activate when the heart's rate falls below the set threshold
• Incision Monitoring, Dressing Changes, and Activity Restrictions
• Patient Education covers Pulse Monitoring, Symptom Awareness, Identification, and Family Education
• Post-operative Restrictions include Immobilization, Arm Movement, and Activity Limitations
• Report any Weakness, Vertigo, Chest pain, or a pulse rate that is too low
• Nursing Interventions include Heart Rate Monitoring, Hydration, and Insertion Site Monitoring