Cardiovascular System

Comprehensive NCLEX-RN Review — Anatomy, Physiology, Pathophysiology, Pharmacology, and Nursing Management

Anatomy & Physiology
Cardiovascular Assessment
Cardiac Diagnostics & Lab Values
ECG Interpretation
Coronary Artery Disease & Angina
Myocardial Infarction
Heart Failure
Hypertension
Valvular Disorders
Endocarditis & Pericarditis
Cardiac Surgery: CABG, Valve Replacement, Pacemaker
Cardiac Medications
Dysrhythmias & Emergency Care
Peripheral Vascular Disorders
Pediatric Cardiology
NCLEX Priority Concepts

1. Anatomy & Physiology of the Heart

Heart Wall Layers

The heart wall consists of three distinct layers:

Pericardium (outer layer): Has an outer fibrous (parietal) layer and an inner serous (visceral/epicardium) layer. The space between these layers is the pericardial space, which contains a small amount of pericardial fluid that reduces friction during heartbeats.
Myocardium (middle layer): The muscular layer of the heart responsible for contraction.
Endocardium (inner layer): The thin lining of the chambers of the heart.

The precordium is the part of the front of the chest wall that overlies the heart and epigastrium — the area auscultated during a cardiac exam.

Chambers of the Heart

The heart has four chambers: Right Atrium, Left Atrium, Right Ventricle, and Left Ventricle.

Clinical Pearl: The left ventricle has the thickest myocardium because it must pump blood against high systemic pressure. It is the workhorse of the heart.

Cardiac Cycle

The cardiac cycle includes contraction (systole) and relaxation (diastole) and has three stages:

Atrial systole — atria contract, pushing blood into ventricles
Ventricular systole — ventricles contract, pushing blood into pulmonary artery and aorta
Complete cardiac diastole — all chambers relaxed, heart fills passively

Major Vessels Connected to the Heart

Vessel	Origin / Termination	Type of Blood
Superior / Inferior Vena Cava	→ Right Atrium	Deoxygenated
4 Pulmonary Veins	Lungs → Left Atrium	Oxygenated
Pulmonary Artery	Right Ventricle → Lungs	Deoxygenated
Aorta	Left Ventricle → Body	Oxygenated

Valves of the Heart

Valve	Type	Location	Sound
Mitral (Bicuspid)	AV Valve	Between L. Atrium and L. Ventricle	S₁
Tricuspid	AV Valve	Between R. Atrium and R. Ventricle	S₁
Aortic	Semilunar	Origin of Aorta	S₂
Pulmonary (Pulmonic)	Semilunar	Origin of Pulmonary Artery	S₂

Chordae tendineae are cord-like tendons attached to the tricuspid and mitral valves that prevent eversion of the valves during ventricular systole. They attach to papillary muscles, which are projections of the myocardium.

Heart Sounds

S₁ (lub): Closure of mitral and tricuspid valves at the start of ventricular systole
S₂ (dub): Closure of aortic and pulmonic valves at the start of ventricular diastole
S₃ (gallop): Abnormal — common in CHF or valvular regurgitation; can be normal in adults < 30 years
S₄ (gallop): Abnormal — common in MI or ventricular hypertrophy
Murmurs: Extra heart sounds from turbulent blood flow; may be physiological (innocent, common in children) or pathological (ASD, VSD, etc.)

Conduction System

Structure	Function	Inherent Rate
SA Node (Sinoatrial)	Primary pacemaker; initiates impulse	60–100 bpm
AV Node (Atrioventricular)	Delays impulse, allowing atrial contraction before ventricular	40–60 bpm
Bundle of His	Divides into Right and Left Bundle Branches	—
Purkinje Fibers	Distribute impulse through ventricles	20–40 bpm

Clinical Pearl: If the SA node fails, the AV node can initiate impulses at 40–60 bpm (junctional escape rhythm). If both fail, the ventricles fire at 20–40 bpm (ventricular escape rhythm) — this is often inadequate to maintain consciousness.

Coronary Circulation

Right Coronary Artery (RCA): Supplies the right atrium, right ventricle, inferior portion of the left ventricle, posterior septal wall, SA node, and AV node.
Left Coronary Artery (LCA) divides into:
- Left Anterior Descending (LAD): Supplies the anterior wall of the left ventricle, anterior ventricular septum, and apex — the "widow maker" if occluded.
- Circumflex Artery: Supplies the left atrium and lateral and posterior surfaces of the left ventricle.

Types of Circulation

Systemic circulation: Oxygenated blood from left ventricle → aorta → body → deoxygenated blood returns via vena cavae to right atrium.
Pulmonary circulation: Deoxygenated blood from right ventricle → pulmonary artery → lungs → oxygenated blood returns via 4 pulmonary veins to left atrium.
Hepatic (portal) circulation: Blood from GI tract organs → liver; interruption causes portal hypertension.

Heart Volumes & Hemodynamics

Term	Definition	Normal Value
Preload (EDV)	Volume of blood in ventricles before contraction	—
Afterload	Resistance ventricles must overcome to eject blood	—
Stroke Volume	Difference between preload and afterload	~70 mL
Ejection Fraction	SV / EDV — percentage of blood ejected	55–70%
Cardiac Output	SV × HR	~4,900 mL/min (4–8 L/min)
CVP	Central venous pressure (right atrial pressure)	3–8 mmHg (4–12 cm H₂O)
PCWP	Pulmonary capillary wedge pressure (L. ventricular pressure)	4–12 mmHg
PAP	Pulmonary artery pressure	< 20 mmHg

KEY POINTS — Anatomy & Physiology:
✔ The heart has 3 layers: pericardium, myocardium, endocardium
✔ 4 chambers: RA, LA, RV, LV (LV has thickest wall)
✔ 4 valves: mitral & tricuspid (AV) close at S₁; aortic & pulmonic close at S₂
✔ Conduction: SA node (60–100) → AV node (40–60) → Bundle of His → Purkinje
✔ RCA supplies SA/AV nodes; LAD supplies anterior LV and septum
✔ Ejection fraction = SV/EDV; Normal > 55%

2. Cardiovascular Assessment

Health History

Key symptoms to assess include: shortness of breath (SOB), cough, dizziness, syncope, palpitations, chest pain, dyspnea, orthopnea (dyspnea relieved by sitting up), paroxysmal nocturnal dyspnea (PND), edema, cyanosis, history of rheumatic fever, STDs (syphilis), obesity, high cholesterol, and hormonal contraceptive use (↑ DVT risk).

Auscultation Areas

Location	Intercostal Space	Sound Heard Best
Aortic Area	2nd right intercostal space	S₂ (aortic closure)
Pulmonic Area	2nd left intercostal space	S₂ (pulmonic closure)
Erb's Point	3rd left intercostal space, sternal border	S₂ best heard here
Tricuspid Area	4th–5th left intercostal space	Tricuspid valve sounds
Mitral Area	5th left intercostal space, midclavicular line	Mitral valve sounds

Peripheral pulses are graded on a scale of 0–4: 0 = absent; 1 = palpable; 2 = normal; 3 = full; 4 = full and bounding (↑ BP, ↑ stroke volume).

BNP (B-type Natriuretic Peptide): Elevated in left ventricular failure (normal < 100 pg/mL). ANP (Atrial Natriuretic Peptide): Elevated in right ventricular failure, can cause nocturia.

3. Cardiac Diagnostics & Lab Values

Cardiac Enzymes

Marker	Rises	Peaks	Returns to Normal	Normal Value
Troponin I	3 hours	18–24 hours	7 days	< 0.5 ng/mL
Troponin T	3 hours	18–24 hours	7 days	< 0.1 ng/mL
CK-MB	4–6 hours	18–24 hours	48–72 hours	< 5% of total CPK
Myoglobin	1 hour	4–6 hours	24–36 hours	Not normally present
LDH (LDH₁ > LDH₂)	24 hours	48–72 hours	10–14 days	140–280 IU/L

Clinical Pearl: Troponin is the gold standard for diagnosing MI. It rises within 3 hours and remains elevated for 7 days. CK-MB peaks faster (18–24 hrs) but returns to normal sooner. Myoglobin rises within 1 hour — useful for early detection but not specific to cardiac muscle.

Serum Lipids

Lipid	Normal / Desired Value
Total Cholesterol	< 200 mg/dL
LDL (Low-Density Lipoprotein)	< 100 mg/dL (ideal)
HDL (High-Density Lipoprotein)	> 60 mg/dL (desired); < 40 mg/dL poor
Triglycerides	< 150 mg/dL

Electrolytes Affecting Cardiac Function

Electrolyte	Normal Range	Hypo- Effects	Hyper- Effects
Potassium (K⁺)	3.5–5.2 mEq/L	Ventricular arrhythmias, flattened T wave, U wave, digoxin toxicity risk	Asystole, peaked T wave, small P wave
Calcium (Ca²⁺)	8.5–11 mg/dL	Prolonged ST and QT interval	Shortened ST, AV block, brady/tachycardia
Magnesium (Mg²⁺)	1.5–2.5 mEq/L	VT, VF, Torsades de Pointes, hypotension	Prolonged PRI, wide QRS

Cardiac Catheterization

Indications: Diagnostic — evaluate anatomical defects, blood flow, conduction disturbances, coronary artery blockages. Therapeutic — stent placement, PTCA, temporary pacemaker.

Right-sided: Catheter via antecubital or femoral vein → SVC/IVC → right atrium
Left-sided (retrograde): Catheter via brachial or femoral artery → aorta → left ventricle

Pre-Test Care	Post-Test Care
Informed consent	Check circulation distal to insertion site
Ask about iodine/shellfish allergy	Check peripheral pulses, color, sensation q15min × 4 hrs
Monitor renal function	Monitor for numbness/tingling
NPO 8–12 hours prior	Keep extremity straight 6–8 hrs
Height, weight, baseline VS, peripheral pulses	Strict bed rest 6–12 hrs
Withhold metformin 24–48 hrs before	Observe site for bleeding/hematoma
Inform patient: warmth, flushing, salty taste, palpitations during procedure	Increase fluid intake; monitor for dysrhythmias, cardiac tamponade

Echocardiogram / TEE

Echocardiogram: Non-invasive ultrasound — no special prep; patient lies still, breathes normally.
Transesophageal Echo (TEE): Invasive — probe inserted via esophagus. Patient NPO, local anesthetic. Post-procedure: monitor gag reflex and swallowing before resuming feeding.

Hemodynamic Monitoring

Device	Measures	Normal	Nursing Care
CVP	Right atrial pressure (preload)	3–8 mmHg	Maintain phlebostatic axis at mid-axillary line; ↑CVP = hypervolemia/CHF; ↓CVP = hypovolemia
Swan-Ganz	PA pressure, PCWP (left-sided pressures)	PAP < 20; PCWP 4–12	Sterile dressing q24h; balloon deflated except during PCWP reading; same position each reading

KEY POINTS — Diagnostics:
✔ Troponin is the gold standard for MI (rises 3 hrs, stays 7 days)
✔ CK-MB < 5% of total CPK; rises 4–6 hrs post-MI
✔ K⁺ 3.5–5.2 — hypokalemia causes U waves; hyperkalemia causes peaked T waves
✔ Mg²⁺ 1.5–2.5 — low Mg²⁺ → Torsades de Pointes
✔ Cardiac cath: NPO, check allergy, withhold metformin. Post-op: bed rest, keep extremity straight, check pulses
✔ CVP 3–8 mmHg; PCWP 4–12 mmHg

4. ECG Interpretation

ECG Grid & Waveforms

On ECG graph paper, the X-axis (horizontal) represents time in seconds, and the Y-axis (vertical) represents voltage in mV.
Each small square = 0.04 sec. Each large square = 0.04 × 5 = 0.2 sec. Five large squares = 1 second.

Wave / Interval	Represents	Normal Duration	Clinical Significance
P wave	Atrial depolarization	—	Absent in atrial fibrillation, atrial standstill
PR Interval (PRI)	Time from atria through AV node	0.12–0.20 sec	Prolonged = 1st degree AV block; variable = Wenckebach
QRS Complex	Ventricular depolarization	< 0.12 sec	Wide = bundle branch block, ventricular rhythms
ST Segment	Complete ventricular depolarization	Isoelectric	Elevation = STEMI; Depression = ischemia
T wave	Ventricular repolarization	—	Inverted = ischemia; Peaked = hyperkalemia
QT Interval	Ventricular systole to end diastole	Men ≤ 0.42; Women ≤ 0.43	Prolonged = risk for ventricular tachyarrhythmias
U wave	—	—	If present, indicates hypokalemia

5 Characteristics of Normal Sinus Rhythm

R-R intervals are constant (regular rhythm)
Rate (atrial and ventricular) 60–100 bpm
P wave in front of every QRS complex
PRI 0.12–0.20 sec
QRS < 0.12 sec

Heart Rate Calculation Methods

6-second method: Count R waves in a 6-second strip × 10 — quick estimate
300 method (regular rhythms): Count large squares between 2 R waves, divide 300 by that number (1 large square = 300 bpm; 2 = 150; 3 = 100; 4 = 75; 5 = 60; 6 = 50)
1500 method (most accurate): Count small squares between 2 R waves, divide 1500 by that number

Stress Test / Exercise ECG

Patient walks on treadmill with increasing intensity while ECG, BP, and symptoms are monitored. Indications: diagnose CAD, evaluate exercise tolerance, assess treatment effectiveness. Contraindications: acute MI, unstable angina, uncontrolled HTN, severe aortic stenosis.

KEY POINTS — ECG:
✔ Normal sinus rhythm: regular, 60–100 bpm, P before every QRS, PRI 0.12–0.20, QRS < 0.12
✔ ST elevation = injury (STEMI); ST depression = ischemia
✔ Prolonged QT = risk for torsades; U wave = hypokalemia; Peaked T = hyperkalemia
✔ HR calculation: 300 ÷ large squares between R waves (regular rhythms)

5. Coronary Artery Disease (CAD) & Angina Pectoris

Coronary Artery Disease

Definition: Narrowing of the coronary arteries with decreased blood supply to the myocardium, primarily caused by atherosclerosis.

Risk Factors: Family history, ↑lipoproteins, smoking, diabetes mellitus, hypertension, obesity, sedentary lifestyle, stress, competitive lifestyle.

Findings: Dyspnea, chest pain, palpitations, syncope, cough, excessive fatigue.

Diagnosis: ↑Serum lipids, cardiac catheterization reveals atherosclerotic lesions.

Antilipemic Medications

Drug Class	Examples	Side Effects	Nursing Implications
Statins (HMG-CoA Reductase Inhibitors)	Atorvastatin, Fluvastatin, Lovastatin, Pravastatin, Rosuvastatin, Simvastatin	GI upset, ↑liver enzymes, Rhabdomyolysis	Periodic LFTs; annual eye exam; NO grapefruit juice (↑risk of liver/renal failure)
Bile Acid Sequestrants	Cholestyramine, Colestipol	GI disturbances	Mix powder well with water/juice; give 1 hr after other meds
Fibrates	Gemfibrozil, Fenofibrate, Clofibrate	GI upset	Monitor LFTs
Other	Ezetimibe, Niacin, Fish Oil	Flushing (niacin)	Niacin: take with food to reduce flushing

Angina Pectoris

Definition: Transient paroxysmal chest pain due to insufficient blood flow to the myocardium resulting in myocardial ischemia.

Types of Angina

Type	Characteristics
Stable (Exertional)	Relieved by rest or nitroglycerin; predictable pattern
Unstable (Preinfarction)	May not be relieved by nitroglycerin; increasing frequency/severity; medical emergency
Variant (Prinzmetal's)	Caused by coronary artery vasospasm; may occur at rest
Intractable	Chronic, incapacitating, unresponsive to interventions

Angina vs. MI Comparison

Feature	Angina	MI
Pain	Temporary, relieved by rest or NTG	Unrelieved by rest or NTG; requires morphine
Cardiac Enzymes	Normal	Elevated
ECG	ST depression or T wave inversion during pain	ST elevation (STEMI) or depression (NSTEMI), T inversion, abnormal Q wave

Nursing Interventions for Angina

Check BP before each dose of nitroglycerin
S/L nitroglycerin: max 3 doses, 5 minutes apart; store in amber, tight container; tingling/burning should be felt
Patients on nitroglycerin should avoid ED drugs (sildenafil, tadalafil, vardenafil) — severe hypotension risk
O₂ 3 L/min as ordered
Reduce stress/anxiety; avoid overexertion, extreme temperatures
Topical nitroglycerin: apply to non-hairy chest area, rotate sites, remove old patch before new one, remove patch for 12 hours daily to prevent tolerance

KEY POINTS — CAD & Angina:
✔ Stable angina: relieved by rest/NTG; Unstable: ↑ risk, may not respond to NTG
✔ S/L NTG: 3 doses max, 5 min apart; call 911 if no relief after 3rd dose
✔ NO ED drugs with nitrates — can cause severe hypotension
✔ Topical NTG: remove for 12 hours daily to prevent tolerance
✔ Statins: avoid grapefruit juice! Monitor LFTs

6. Myocardial Infarction (MI)

Definition: Death of myocardial cells from inadequate oxygenation, characterized by localized necrosis with subsequent healing, scar formation, and fibrosis.

Findings

Substernal chest pain radiating to neck, shoulder, back, arms — often crushing in quality
Levine's sign: Clutching of the chest (fist over sternum)
Pain unrelieved by rest or nitroglycerin; relieved only by morphine
Cool, clammy, ashen skin; apprehension; N/V; dyspnea; elevated temperature
Rales/crackles, dysrhythmias, S₄ gallop
Location-dependent: RCA → inferior MI; LAD → anterior/septal MI; Circumflex → posterior/lateral MI

Diagnosis

Elevated cardiac enzymes (troponin, CK-MB)
↑ESR, ↑cholesterol, ↑WBC (appears day after MI, remains ↑ for 1 week)
ECG: ST elevation, T wave inversion, abnormal Q wave
Cardiac catheterization

Management: MONA Therapy

Intervention	Purpose
Morphine	Relieves pain and anxiety; vasodilation → ↓preload, ↓afterload, ↓cardiac workload, ↓O₂ demand
Oxygen	2–4 L/min to improve oxygenation
Nitrates	Vasodilation, ↓preload
Aspirin	Antiplatelet effect; reduces mortality

Additional: Beta blockers (metoprolol), establish IV line, bed rest with semi-Fowler's, 12-lead ECG, monitor urinary output (min 30 mL/hr), hemodynamic monitoring.

Thrombolytic Agents

Agent	Side Effect	Antidote
tPA (Alteplase, Activase)	Bleeding	Amicar (aminocaproic acid)
Streptokinase
Urokinase

Surgical Interventions

PTCA (Percutaneous Transluminal Coronary Angioplasty) — dilates stenosed artery
Stent placement — prevents re-occlusion
Atherectomy — removes plaque via cutting chamber and rotating blade
Laser angioplasty — vaporizes plaque
CABG — bypass surgery for multiple blocks

Nursing Management

Bed rest; monitor output; administer medications as ordered
Monitor for complications: Heart failure, arrhythmias, pulmonary edema, thrombophlebitis, pericarditis, cardiogenic shock
Discharge instruction: Low Na, low cholesterol diet; regular walking (aerobic exercise); sexual activity may resume by 4–6 weeks

Clinical Pearl: Time is muscle! Door-to-balloon time should be < 90 minutes for PCI. Every minute of delay increases myocardial damage. Administer aspirin immediately on suspecting MI.

KEY POINTS — MI:
✔ MONA: Morphine, Oxygen, Nitrates, Aspirin — the cornerstone of MI management
✔ Troponin is the gold standard diagnostic marker
✔ Complications: heart failure, arrhythmias, cardiogenic shock, pericarditis
✔ Thrombolytics must be given within 6 hours of symptom onset for maximum benefit

7. Heart Failure (Congestive Heart Failure)

Definition: The heart is unable to pump enough blood to meet the metabolic demands of the body.

Left-Sided vs. Right-Sided Heart Failure

Feature	Left-Sided Failure	Right-Sided Failure
Causes	LV damage from MI, HTN, aortic valve disease, mitral stenosis	LV failure, RV infarction, pulmonary stenosis, PE, COPD/CF/PH (Cor Pulmonale)
Key Signs	Dyspnea, orthopnea, PND, rales/crackles, S₃, wheezing, cyanosis, pallor, decreased peripheral pulses, oliguria, pink frothy sputum	Anorexia, weight gain, dependent edema, hepatomegaly, cool extremities, JVD, positive hepatojugular reflex, nocturia
Hemodynamics	↑PAP, ↑PCWP, ↑BNP (>100)	↑CVP, ↑SGPT (ALT)
Pulse	Pulsus alternans (alternating strong/weak)	—
Ejection Fraction	Systolic HF: EF < 40% (reduced); Diastolic HF: EF normal (preserved)	—

Systolic vs. Diastolic Heart Failure

Systolic HF (HFrEF): Impaired contractility → ↓EF (< 40%) — heart can't pump blood out
Diastolic HF (HFpEF): Impaired relaxation → normal EF — heart can't fill properly (stiff ventricle)

Medical Management

Medication	Key Points
Digoxin	Therapeutic level 0.8–2.0 ng/mL. SE: N/V/D, bradycardia, lethargy, photophobia, diplopia, yellow-green halos. Hold if HR < 60 (adults) or > 100. Monitor K⁺; hold if K⁺ < 3.5. Antidote: Digibind
Diuretics	Furosemide (Lasix) — monitor K⁺, give in morning
Potassium Supplements	Given with loop diuretics to prevent hypokalemia
IABP (Intra-aortic balloon pump)	Balloon in descending thoracic aorta; inflates during diastole, deflates during systole; triggered by ECG; uses helium or CO₂

Nursing Care for Heart Failure

Administer medications 1 hour before or 2 hours after feeding
Diet: Sodium-restricted, potassium-rich, low cholesterol
Fluid restriction as ordered
Daily weight — report gain > 1–2 kg in 2 days
Meticulous skin care; balance rest and activity
Emergency care for pulmonary edema if develops

Pulmonary Edema (Medical Emergency)

Causes: Left-sided heart failure, rapid IV fluid administration.

Findings: Pink frothy sputum, severe dyspnea, cough, tachycardia, pallor, wheezing, rales, diaphoresis, JVD, ↓pO₂, ↑pCO₂, ↑CVP.

Management: Morphine, diuretics, digoxin, aminophylline, nitroglycerin, nesiritide, phlebotomy (300–500 mL), high concentration O₂ (40–60%), CVP monitoring, semi-Fowler's or over-bed table, prepare for intubation.

KEY POINTS — Heart Failure:
✔ Left-sided: "Lungs" — dyspnea, rales, PND, pink frothy sputum
✔ Right-sided: "Body" — edema, JVD, hepatomegaly, weight gain
✔ Systolic HF: ↓EF; Diastolic HF: normal EF (stiff ventricle)
✔ Digoxin: hold if HR < 60 or K⁺ < 3.5; watch for toxicity (yellow-green halos)
✔ Daily weight — gain > 1–2 kg in 2 days = fluid retention

8. Hypertension

Definition: Persistent elevation of systolic BP ≥ 140 mmHg and/or diastolic BP ≥ 90 mmHg.

Types of Hypertension

Type	Characteristics
Primary (Essential)	Associated with aging, loss of elasticity of blood vessels. Risk: aging, family history, smoking, stress, obesity, ↑Na, African American males
Secondary	Associated with other disease conditions (renal, endocrine, etc.)
Benign	Moderate rise, gradual onset, prolonged course. Stage 1: 140–159/90–99; Stage 2: ≥160/≥100
Malignant (Crisis)	>180/120 mmHg. Rapid onset, short course. Can cause stroke, encephalopathy, renal failure, MI. S/S: headache, blurred vision, altered LOC, dyspnea, cyanosis, seizures

General Findings of Hypertension

Occipital headache, visual disturbances, dizziness, chest pain, tinnitus, epistaxis, flushed face, polyuria, dyspnea.

Complications

Loss of vision, CVA (stroke), CHF, renal failure.

Nursing Management for HTN

Record BP in all 3 positions and both arms
Do not miss doses; do not abruptly discontinue drugs (rebound HTN)
Avoid hot bath, alcohol, strenuous exercise within 3 hours of taking meds
Sodium restriction to 2 g/day; minimize canned foods
Stress management, aerobic exercise, smoking cessation, weight reduction
Malignant HTN: IV antihypertensives; monitor VS/BP every 5 min; bed rest with HOB 45°

See Cardiac Medications section below for detailed antihypertensive drug classes.

KEY POINTS — HTN:
✔ 140/90 is the threshold for diagnosis
✔ Malignant HTN > 180/120 = medical emergency
✔ Never abruptly stop antihypertensives — rebound hypertension
✔ Lifestyle: low Na diet, exercise, weight loss, smoking cessation

9. Valvular Disorders

Valvular Stenosis vs. Regurgitation

Disorder	Pathophysiology	Key Findings
Mitral Stenosis	Narrowed mitral valve opening → ↓blood flow from LA to LV → ↑LA pressure → pulmonary HTN	Dyspnea, fatigue, hemoptysis, atrial fibrillation, S₁ loud, opening snap
Mitral Regurgitation	Incomplete closure → blood flows back into LA during systole → LA enlargement	Dyspnea, fatigue, holosystolic murmur at apex
Aortic Stenosis	Narrowed aortic valve → ↑LV pressure → LV hypertrophy → ↓CO	Syncope, angina, dyspnea on exertion, systolic ejection murmur at right 2nd ICS
Aortic Regurgitation	Incomplete closure → blood flows back into LV during diastole → LV volume overload	Water-hammer pulse, wide pulse pressure, diastolic murmur at left 3rd ICS

Management: Valve replacement (mechanical or bioprosthetic) or valvuloplasty. Patients with mechanical valves require lifelong anticoagulation (warfarin). Bioprosthetic (tissue) valves may not require long-term anticoagulation but have limited durability.

Clinical Pearl: Patients with valvular disease need prophylactic antibiotics before dental or invasive procedures to prevent infective endocarditis. Always check for history of rheumatic fever!

10. Endocarditis & Pericarditis

Infective Endocarditis

Definition: Inflammation of the endocardium, leading to deposit of fibrin and platelets on mitral and aortic valves causing stenosis and insufficiency.

Causative organisms: Beta-hemolytic streptococcus, Gonococcus, Staphylococcus aureus.

Risk factors: Open heart procedures, rheumatic heart disease, GU/OB-GYN procedures, dental procedures (3–6 months prior), invasive monitoring, IV drug use, prosthetic valves.

Sign/Symptom	Description
Fever, chills	Most common presenting symptoms
Cough, dyspnea	Pulmonary congestion
Murmurs	New or changing heart murmur
Petechiae	Small red/purple spots on skin or mucous membranes
Splenomegaly	Enlarged spleen
Clubbing	Fingertip enlargement from chronic hypoxia
Janeway Lesions	Non-tender hemorrhagic lesions on palms/soles
Osler's Nodes	Reddish, tender lesions on pads of fingers/hands/toes
Splinter Hemorrhages	Linear hemorrhages under nails

Management: Antibiotics based on culture, antipyretics, surgical valve replacement for damaged valves. Emphasize prophylactic antibiotics before invasive procedures.

Pericarditis

Definition: Inflammation of the parietal and visceral pericardium.

Causes: Secondary to bacterial/viral/fungal infection, acute MI, radiation, neoplasms, uremia, medications (procainamide, hydralazine, doxorubicin), collagen diseases (SLE, RA).

Findings: Chest pain radiating to left shoulder/neck/back, aggravated by inspiration/coughing/swallowing, worse supine, relieved leaning forward, hemoptysis, tachycardia, fever, pericardial friction rub, cyanosis/pallor, paradoxical pulse, JVD, ↑WBC/ESR/SGOT, ECG: ST elevation on all leads.

Management: Pain management, antibiotics, corticosteroids/salicylates/indomethacin to reduce inflammation.

KEY POINTS — Endocarditis & Pericarditis:
✔ Endocarditis: Janeway lesions (non-tender) vs. Osler's nodes (tender)
✔ Prophylactic antibiotics before dental/invasive procedures for high-risk patients
✔ Pericarditis pain: worse supine, better leaning forward; ST elevation on all leads
✔ Cardiac tamponade: Beck's triad (muffled heart sounds, hypotension, JVD) — emergency!

11. Cardiac Surgery

CABG (Coronary Artery Bypass Graft)

Procedure: An obstructed coronary artery is replaced with a graft — most frequently the saphenous vein, brachial artery, mammary artery, or synthetic/porcine grafts.

Traditional: Sternotomy with extracorporeal circulation (ECC)
MIDCAB (Minimally Invasive): Thoracotomy (incision between ribs) — faster recovery but potentially more pain

Pre-Op Care	Post-Op Care
Teach deep breathing/coughing with splinting	Monitor respiratory status; encourage coughing, deep breathing
Explain equipment (hemodynamic monitoring, ET tube/ventilator, chest tube)	Hemodynamic monitoring; Monitor ECG for dysrhythmias
	Administer anticoagulants as ordered
	Monitor fluid/electrolytes; hourly urine output (<30 mL/hr = report)
	Chest tube drainage: report >100–150 mL/hr or >500 mL/24 hrs
	Effective pain management
	Assess VS and SpO₂ before ambulation; D/C if BP drops 10–20 mmHg or HR ↑ >10 bpm

Discharge Teaching for CABG

Daily walking with gradual increase in distance
Avoid heavy lifting, continuous arm movement; no driving until permitted
Sexual activity may resume by 3rd–4th week (can climb 2 flights of stairs or walk 1 block without symptoms)
Diet: low fat, low sodium, low calorie

Pacemaker

Indications: 2nd or 3rd degree AV block, bundle branch block, acute MI with Mobitz II, symptomatic bradycardia, Adams-Stokes attack, sick sinus syndrome.

Type	Description
Fixed Rate	Fires at preset rate regardless of patient's rhythm
Demand	Fires only when patient's HR drops below preset rate
Temporary - Transcutaneous	Non-invasive; 2 large electrode patches on chest and back
Temporary - Transvenous	Invasive; lead wire inserted via antecubital, femoral, jugular, or subclavian vein
Permanent	Generator implanted subcutaneously under clavicle; lithium battery lasts ~10 years; function checked q3 months

Nursing Care for Pacemaker

Monitor site for signs of infection until healing complete
Monitor HR for full minute; report deviation from preset rate
Observe pacemaker spikes on ECG
Monitor for malfunction: weakness, fainting, dizziness, hypotension
Monitor electrolytes (especially potassium)
Wear loose clothing; avoid contact sports
Avoid electromagnetic fields: MRI, airport scanners, weapon detectors, transmitter towers, antitheft devices
Carry ID bracelet with pacemaker information; periodic hospitalization for battery change

Cardiac Tamponade

Definition: Accumulation of blood/fluid in the pericardium preventing adequate ventricular filling, can lead to cardiogenic shock.

Beck's Triad (Classic Signs): Muffled/distant heart sounds, low arterial BP, distended neck veins.

Other findings: Chest pain, tachycardia, pericardial friction rub, paradoxical pulse, sudden cessation of chest drainage after CABG, elevated CVP, ↓Hgb/Hct.

Management: CVP monitoring, pericardiocentesis, prepare for return to OR.

KEY POINTS — Cardiac Surgery:
✔ CABG post-op: monitor chest tube drainage (>100 mL/hr = report), urine output (<30 mL/hr = report)
✔ Pacemaker: avoid MRI & airport scanners; carry ID card; lithium battery lasts ~10 yrs
✔ If pacemaker fails: assess for dizziness, syncope, hypotension
✔ Cardiac tamponade: Beck's triad — muffled heart sounds, hypotension, JVD

12. Cardiac Medications — Complete Drug Table

Cardiac Glycosides

Drug	Action	Side Effects	Nursing Considerations
Digoxin	↑Contractility, ↓HR	N/V/D, bradycardia, lethargy, photophobia, diplopia, yellow-green halos, arrhythmias	Hold if HR <60 (adults); check K⁺; hold if K⁺ <3.5; therapeutic level 0.8–2.0; antidote: Digibind

Beta Blockers (β-Blockers)

Class	Examples	Action	Side Effects	Nursing Implications
1st Gen (Non-selective)	Propranolol, Nadolol, Labetalol, Pindolol, Timolol	Block β-receptors → ↓HR, ↓contractility, ↓BP	Bradycardia, CHF, bronchospasm, hypoglycemia, impotence, depression, fatigue	Contraindicated in asthma; monitor HR/BP before giving; do not stop abruptly (may exacerbate ischemia); mask signs of hypoglycemia
2nd Gen (Cardioselective)	Metoprolol, Atenolol, Bisoprolol
Non-selective α/β	Carvedilol

ACE Inhibitors & ARBs

Class	Examples	Action	Side Effects	Nursing Implications
ACE Inhibitors	Captopril, Enalapril, Lisinopril, Ramipril, Quinapril, Benazepril	Inhibit conversion of angiotensin I → angiotensin II → vasodilation, ↓aldosterone	Stomatitis, taste loss, tongue ulcers, dry cough, hyperkalemia, pancytopenia, renal damage, proteinuria, angioedema, teratogenic	Monthly urine protein + CBC; CI in renal insufficiency; avoid K⁺-sparing diuretics; monitor K⁺
ARBs	Losartan, Valsartan, Candesartan, Telmisartan	Block angiotensin II at receptor sites → ↓vasoconstriction, ↓aldosterone	Similar to ACE-I but less cough	Same monitoring as ACE-I

Calcium Channel Blockers

Examples	Action	Side Effects	Nursing Implications
Nifedipine, Nicardipine, Amlodipine, Verapamil, Diltiazem	Block Ca²⁺ entry → ↓cardiac contractility, ↓HR, vasodilation, ↓BP	Dizziness, hypotension, bradycardia, palpitations, flushing, arrhythmias, diarrhea/constipation, gingival hyperplasia	CI in CHF; avoid with β-blockers; monitor for hypotension with S/L nifedipine

Diuretics

Class	Examples	Action	Side Effects	Nursing Implications
Loop Diuretics	Furosemide, Torsemide, Ethacrynic Acid, Bumetanide	Act on Loop of Henle; block Na⁺/water reabsorption	Hyponatremia, hypokalemia, dehydration	Give in AM; give K⁺ supplements; only choice for renal patients; not recommended in pregnancy
Thiazides	HCTZ, Chlorthalidone, Metolazone	Promote renal excretion of Na⁺, K⁺, water	Hypokalemia, hyperuricemia, hypercalcemia, hyperglycemia, sexual dysfunction	CI in sulfa allergy; CI in renal insufficiency
K⁺-Sparing	Spironolactone, Triamterene, Amiloride, Eplerenone	Block aldosterone; excrete Na⁺/water, retain K⁺	Gynecomastia, menstrual irregularities, hirsutism, impotence	No K⁺ supplements; avoid salt substitutes; CI in renal insufficiency/hyperkalemia
Osmotic	Mannitol, Glycerin, Isosorbide	↑Osmotic pressure of glomerular filtrate	Pulmonary edema, N/V, headache, hyponatremia, dehydration	Mainly for ↑ICP and ↑IOP

Nitrates / Anti-anginals

Drug	Route	Action	Nursing Considerations
Nitroglycerin	S/L, IV, topical (cream/patch)	Vasodilation → ↓preload, ↓afterload, ↓O₂ demand	Check BP before each dose; max 3 S/L doses 5 min apart; store in amber glass; avoid ED drugs (sildenafil, tadalafil, vardenafil)
Isosorbide Dinitrate (Isordil)	PO (long-acting)	Same as NTG	Also used for chronic angina prophylaxis
Topical NTG (Transderm-Nitro)	Patch/cream	Same as NTG	Apply to non-hairy chest; rotate sites; remove old before new; remove 12 hrs daily to prevent tolerance; do not massage

Anticoagulants & Antiplatelets

Drug	Mechanism	Monitoring	Antidote	Nursing
Unfractionated Heparin	Blocks prothrombin → thrombin	PTT (goal 1.5–2× normal)	Protamine Sulfate	IV via pump; SQ: 90° angle, 26–27G, don't aspirate, don't massage
LMWH (Enoxaparin, Dalteparin)	Factor Xa inhibition	Anti-Xa levels	Protamine (partial)	Given SQ; do not expel air bubble; rotate sites
Warfarin (Coumadin)	Blocks vitamin K-dependent clotting factors	PT/INR (INR 2–3 typical)	Vitamin K (Aquamephyton)	Avoid sudden ↑ in vitamin K-rich foods; bleeding precautions (soft toothbrush, no floss)
Aspirin	Antiplatelet (COX inhibition)	—	—	Give with food to reduce GI irritation
Clopidogrel (Plavix)	ADP receptor blocker	—	—	Often combined with aspirin for ACS
Other Antiplatelets	Prasugrel, Ticagrelor, Abciximab, Dipyridamole	Various mechanisms	—	Monitor for bleeding

Antiarrhythmics

Class	Examples	Use	Key Points
Class I (Na⁺ channel blockers)	Lidocaine, Procainamide, Quinidine	Ventricular arrhythmias	Lidocaine: IV push for PVCs/VT; monitor for CNS toxicity
Class II (β-blockers)	Propranolol, Metoprolol	SVT, rate control in AFib	—
Class III (K⁺ channel blockers)	Amiodarone, Sotalol	VT, VF, AFib	Amiodarone: can cause pulmonary fibrosis, thyroid dysfunction, corneal deposits
Class IV (Ca²⁺ channel blockers)	Verapamil, Diltiazem	SVT, AFib rate control	—

KEY POINTS — Cardiac Medications:
✔ Digoxin: hold if HR <60 or K⁺ <3.5; toxicity → yellow-green halos, bradycardia, N/V
✔ β-blockers: don't stop abruptly; CI in asthma; mask hypoglycemia
✔ ACE-I: dry cough common; monitor K⁺ and renal function; teratogenic
✔ Diuretics: give in AM; loop diuretics require K⁺ supplementation
✔ Heparin: PTT monitoring; antidote = protamine sulfate
✔ Warfarin: INR 2–3; antidote = vitamin K; avoid sudden changes in vitamin K intake
✔ Nitrates + ED drugs = severe hypotension — absolutely contraindicated!

13. Dysrhythmias & Emergency Cardiac Care

Premature Ventricular Contractions (PVCs)

Irritable focus in ventricle fires prematurely — no P wave, wide QRS (≥ 0.12 sec)
Causes: electrolyte imbalances, digoxin toxicity, CHF, hypoxia, MI, stimulants
Patterns: Bigeminy (every 2nd beat), Trigeminy (every 3rd), Couplet (2 in a row)
Management: IV Lidocaine, Amiodarone, Quinidine, Procainamide

Ventricular Tachycardia (VT)

Rate 150–250 bpm; P waves hidden; QRS > 0.12 sec
Causes: acute MI, CAD, hypokalemia, digoxin toxicity
Stable: O₂ + antiarrhythmics; unstable: DC cardioversion; pulseless: defibrillation + CPR

Ventricular Fibrillation (VF)

Chaotic rhythm, no distinguishable waves → cardiac arrest within 90 seconds
Management: Defibrillate (200J → 300J → 360J), CPR, Epinephrine, Amiodarone, Lidocaine

Defibrillation vs. Cardioversion

Feature	Defibrillation	Cardioversion
Purpose	Terminate VF/pulseless VT	Convert SVT, AFib, VT (with pulse)
Synchronized?	No (asynchronous)	Yes (synchronized to R wave)
Energy	200J → 300J → 360J	50–100J (lower)
Procedure	Emergency — no sedation	Elective — sedation given

Nursing Care During Defibrillation/Cardioversion

Do NOT touch patient or bed during shock delivery — announce "ALL CLEAR"
Stop O₂ during procedure (fire hazard)
Pre-cardioversion: hold digoxin 48 hrs; informed consent; sedation (midazolam, propofol, fentanyl)
Post: maintain airway, O₂ as ordered, monitor VS and rhythm

Implantable Cardioverter-Defibrillator (ICD)

For patients with spontaneous VT/VF or unresponsive to medications
Nursing: wear loose clothing, avoid contact sports, avoid MRI/weapon detectors, carry medical alert bracelet, encourage CPR training for family

CPR Summary

Check unresponsiveness → call code → check carotid pulse
Compression: lower half of sternum, at least 2" deep (adults), 100–120/min
Ratio: 30:2 (adults, 1 or 2 rescuers); 15:2 (children/infants, 2 rescuers)
Push hard, push fast, allow full chest recoil, avoid excessive ventilation
Switch compressors every 2 minutes; gap between cycles ≤ 10 seconds

KEY POINTS — Dysrhythmias & Emergencies:
✔ PVC: wide QRS, no P wave — treat cause (electrolytes, hypoxia)
✔ VT: rate 150–250 — pulse = cardiovert; no pulse = defibrillate
✔ VF: immediate defibrillation — "shockable rhythm"
✔ Defib: asynchronous; Cardioversion: synchronized to R wave
✔ "All clear" before shocking — stop O₂
✔ CPR: 30:2, at least 2" depth, allow chest recoil

14. Peripheral Vascular Disorders

Arterial vs. Venous Ulcers

Feature	Arterial Ulcer	Venous Ulcer
Cause	Smoking, arterial occlusive disorders, diabetes	Thrombophlebitis, varicose veins, edema
Pulses	Diminished	Normal (may be hard to palpate due to edema)
Capillary Refill	Prolonged	Normal
Pain	Claudication	No claudication
Appearance	Necrotic, black/blue	Non-healing, granulation tissue, brownish/leathery
Management	Femoral-popliteal bypass, amputation	Prolonged dressing, Unna boot, elastic stockings, elevation

Deep Vein Thrombosis (DVT)

Risk factors: Obesity, CHF, MI, pregnancy, smoking, trauma, dehydration, OCPs, prolonged immobility, post-op.

Findings: Superficial — pain, tenderness, induration, redness along vein. DVT — swelling, tenderness, positive Homan's sign (pain on dorsiflexion), cyanosis, ↑WBC/ESR, ↑D-dimer.

Management: Anticoagulation (heparin → warfarin). Surgical: venous thrombectomy, IVC filter (umbrella-like device in IVC).

Discharge teaching: Avoid prolonged standing/sitting, crossing legs, smoking, prolonged flying. Perform dorsiflexion exercises. Maintain hydration. Swimming is good exercise.

Pulmonary Embolism (PE)

Definition: Usually related to a detached venous thrombus from deep veins of leg, right heart, or pelvic area — often affects lower lobes of lungs due to higher blood flow.

Findings: Pleuritic chest pain, severe dyspnea, tachypnea, rales, apprehension, tachycardia, hemoptysis, ↑temperature, shock symptoms if severe, ↑V/Q ratio, ↑D-dimer.

Management: Anticoagulants, thrombolytics, narcotics for pain. Surgery: embolectomy.

KEY POINTS — Vascular:
✔ DVT: Homan's sign (pain on dorsiflexion), ↑D-dimer — anticoagulate
✔ PE: pleuritic chest pain + dyspnea + tachypnea = suspect PE
✔ Prevent DVT: ambulation, compression devices, hydration, dorsiflexion exercises
✔ Arterial ulcer: necrotic, diminished pulses, claudication; Venous ulcer: granulation, edema, brownish skin

15. Pediatric Cardiology

Fetal Circulation

Umbilical vein brings oxygenated blood from placenta → IVC via ductus venosus
Blood passes from right atrium to left atrium through foramen ovale
Blood pumped from right ventricle → pulmonary artery → redirected to aorta via ductus arteriosus
Blood returns to placenta via 2 umbilical arteries (from internal iliac/hypogastric arteries)

Normal Circulatory Changes at Birth

Ductus venosus → ligamentum venosum (within 1 week)
Foramen ovale → fossa ovalis (within 1 week)
Ductus arteriosus → ligamentum arteriosum (2–3 weeks)
Hypogastric/umbilical arteries → ligamentum teres

Congenital Heart Defects

Defect	Type	Description	Key Features	Management
ASD	Acyanotic	Opening in atrial septum → L→R shunt	Systolic ejection murmur at upper left sternal border; dyspnea	Amplifier closure or surgical closure (2–4 yrs)
VSD	Acyanotic	Opening in ventricular septum — most common CHD	Holosystolic murmur at lower left sternal border; FTT, CHF, frequent infections	Surgical closure or PA banding
PDA	Acyanotic	Failure of ductus arteriosus to close	Machinery murmur; higher in preemies; can cause CHF	Indomethacin (in preemies); ligation; coil
Coarctation of Aorta	Acyanotic	Stenosis distal to left subclavian artery	↑BP in arms, ↓BP in legs; warm upper body, cool lower body; ↑risk of stroke	Resection & anastomosis
Tetralogy of Fallot (TOF)	Cyanotic	4 defects: VSD, pulmonary stenosis, overriding aorta, RV hypertrophy	TET spells (cyanotic spells); squatting; clubbing; polycythemia; harsh systolic murmur	Palliative: Blalock-Taussig shunt; Corrective: total repair; knee-chest for TET spells

TET Spell Management

TET spells (acute hypoxic episodes): precipitated by crying, feeding, defecation. S/S: cyanosis, tachypnea, tachycardia, altered LOC, flaccidity → may progress to seizure, CVA, or death.

Management: Morphine, Propranolol, Prostaglandins, Oxygen, Knee-chest position. If found squatting — allow child to stay in that position.

Rheumatic Fever

Definition: Cross-reactivity disorder after Group A β-hemolytic strep infection (usually strep throat). Peak incidence in school-age children.

Major Symptoms (Jones Criteria)	Minor Symptoms
Carditis (SOB, hepatomegaly, edema, valve damage)	Recent strep infection history
Polyarthritis (migratory joint inflammation)	↑ESR
Sydenham's Chorea (purposeless involuntary movements)	↑ASO titer
Subcutaneous nodules (firm, non-tender on bony prominences)	↑CRP
Erythema Marginatum (transient, non-pruritic rash)

To confirm RF: 2 major symptoms OR 1 major + 2 minor symptoms.

Management: Penicillin (monthly injection until age 20 or 5 yrs after attack, whichever is longer); erythromycin if allergic to penicillin. NSAIDs, steroids. Bed rest until labs normalize. With chorea: ↓stimulation, safety precautions, assist with feeding.

KEY POINTS — Pediatric:
✔ Foramen ovale closes → fossa ovalis (1 wk); Ductus arteriosus → ligamentum arteriosum (2–3 wks)
✔ Most common CHD: VSD
✔ TOF: 4 defects — if child squats, allow it (knee-chest position increases systemic vascular resistance)
✔ TET spells: O₂, morphine, knee-chest, propranolol
✔ Rheumatic fever: Jones criteria — 2 major or 1 major + 2 minor; penicillin prophylaxis until age 20

16. NCLEX Priority Concepts — Cardiovascular

TOP NCLEX PRIORITIES FOR CARDIOVASCULAR:

1. Airway, Breathing, Circulation (ABCs): Always assess and stabilize the airway and breathing first. In cardiac arrest, start chest compressions immediately (C-A-B).

2. Chest Pain Assessment: PQRST (Provocation, Quality, Radiation, Severity, Timing). Differentiate angina (relieved by rest/NTG) from MI (requires morphine).

3. MONA for MI: Morphine, Oxygen, Nitroglycerin, Aspirin — administer immediately.

4. Heart Failure: Daily weight is the most sensitive indicator of fluid status. Assess for JVD, edema, rales. Give diuretics in AM. Hold digoxin if HR <60.

5. Anticoagulant Safety: Bleeding precautions (soft toothbrush, no floss, electric razor). Monitor PTT (heparin) or INR (warfarin). Know antidotes.

6. Potassium & Cardiac Function: Hypokalemia → arrhythmias, U waves, digoxin toxicity. Hyperkalemia → peaked T waves, asystole.

7. Defibrillation vs. Cardioversion: Defibrillation = emergency, no sedation, asynchronous. Cardioversion = elective, sedation, synchronized to R wave. "ALL CLEAR" before shocking.

8. Cardiac Tamponade: Beck's triad (muffled heart sounds, hypotension, JVD). Emergency pericardiocentesis.

9. Post-Cardiac Catheterization: Keep affected extremity straight, bed rest, check pulses q15min × 4 hrs. Monitor for bleeding/hematoma.

10. Patient Education: Low Na/low cholesterol diet, smoking cessation, exercise (walking), stress management, medication compliance, recognition of s/s (chest pain, SOB, edema).