Cardiovascular Pathology – Part 2 Comprehensive Notes

Coronary Artery Disease (CAD)

• Pathophysiology identical to peripheral arterial disease (atherosclerosis).

  • Four histologic stages to recall in order:

  1. Response-to-injury → endothelial dysfunction.

  2. Fatty streak formation (see vivid slide image).

  3. Fibrous plaque with lipid deposit.

  4. Complicated lesion (plaque rupture & thrombosis).

• Risk factors (know for “select-all-that-apply” items)

  • Modifiable: high cholesterol, hypertension, diabetes, smoking, physical inactivity, obesity.

  • Non-modifiable: \text{age}, genetics/family history, male sex.

  • Emphasise that most exam stems mix modifiable & non-modifiable—read carefully.

Angina Pectoris: Stable vs. Unstable

• Stable Angina

  • Transient, predictable chest pain on exertion; resolves with rest or nitroglycerin.

  • Normal ECG between episodes; no troponin rise ⇒ no cell death (pure ischemia).

• Unstable Angina

  • Chest pain even at rest; thrombus on ruptured plaque produces partial lumen occlusion.

  • ECG: normal, T-wave inversion, or ST depression possible.

  • NO troponin rise (still no infarction) – key board question.

Acute Coronary Syndrome (ACS)

Diagnostic hierarchy

Non-invasive → invasive

1. Resting ECG.

2. Treadmill stress test.

3. Nuclear stress test or dobutamine stress echo.

4. Cardiac CT.

5. Angiography / PCI (balloon angioplasty) – both diagnosis and therapy.

NSTEMI vs. STEMI (memorise table)

Sudden Cardiac Death (SCD)

• \approx 350\,000 U.S. deaths / year.

• #1 cause = ventricular arrhythmia (esp. VFib) post-MI.

• CPR/AED resets rhythm (“electrical problem” vs. MI = “circulation problem”).

• Always correlate monitor with patient (machines misread!).

Heart Failure (HF)

Right- vs. Left-Sided HF (draw flow diagram!)

Systolic vs. Diastolic HF

Compensatory Mechanisms (short-term helpful, long-term harmful)

• SNS → catecholamines ↑HR & ↑SVR.

• RAAS → \uparrow aldosterone, Na/H_2O retention.

• ADH → water reabsorption.

• Chronic activation ⇒ hypertrophy, worsening HF.

Factors precipitating Acute Decompensation

• High-Na diet, fluid overload.

• Medication non-adherence (diuretics, ACE-I, anti-arrhythmics).

• Uncontrolled HTN.

• New arrhythmia or MI.

• Intercurrent illness / surgery (↑ metabolic demand).

Congenital Heart Defects

Endocardial & Myocardial Inflammations

Rheumatic Heart Disease (RHD)

• Auto-immune sequela of repeated strep throat infections.

• Inflammation of valves (mitral > aortic).

• Takes years; S/Sx: fever, migratory arthritis, scarlet rash, chorea, murmurs.

Infective Endocarditis (IE)

• Bacterial vegetation on valves (IV-drug use, prosthetic valves).

• Fever + new murmur! Classic peripheral signs:

  • Splinter haemorrhages, Osler nodes, Janeway lesions, Roth spots.

• Complications: septic emboli → stroke, MI, glomerulonephritis.

Myocarditis vs. Pericarditis

Pericardial Effusion vs. Tamponade

Valvular Disorders

Terminology

• Stenosis = narrowed, tight valve (flow obstruction).

• Regurgitation/Insufficiency = valve doesn’t seal → backward flow.

Mitral Valve

• Stenosis (diastolic): rheumatic fever; ↓CO, pulmonary edema; exertional dyspnea, cough.

• Regurgitation (systolic): MI rupture, RHD; ↓CO, pulmonary edema; often asymptomatic early.

Aortic Valve

• Stenosis (systolic): calcification, RHD; LV hypertrophy, angina, syncope, dyspnea.

• Regurgitation (diastolic): congenital or RHD; LV dilation, flash pulmonary edema, nocturnal dyspnea.

High-Yield “Red-Star” Reminders

• Non-STEMI & STEMI both elevate troponin; unstable angina does not.

• Right HF symptoms = “systemic”; Left HF symptoms = “pulmonary.”

• Tetralogy = only common cyanotic defect on exam lists.

• Myocarditis = viral muscle inflammation → arrhythmia risk; Pericarditis = positional chest pain.

• Tamponade = Beck’s triad; treat immediately.

• New fever + murmur? Think infective endocarditis; order blood cultures.

• Systolic HF → ↓EF; Diastolic HF → preserved EF.

End of comprehensive cardiovascular part 2 review – suitable as standalone study sheet.