Pulmonary and Cardiac Conditions Quiz

Cardiology Review Notes (Weeks 1-3)

• This review supplements, not replaces, student notes.
• Review focuses on high-yield topics and key points.
• The presentation's opinions are the presenter's own.

General Tips/Advice/Reassurances

• The practical exams are fair.
• Complete the weekly quizzes and ECG quizzes.
• Understand the drugs, not just memorize them.

Cardiovascular Basics

• Vessels:
  • Arteries: High pressure, distensible (less so with age). Control microvascular flow. Resistance vessels (large pressure change), thin walls.
  • Arterioles: Control microvascular flow, resistance vessels, slow flow due to large cross-sectional area, thin walls.
  • Capillaries: Low pressure, capacitance vessels (distensible), thin walls.
• Plasma skimming: Blood from larger vessels enters at 40%. Flow profile develops a parabolic shape. High shear in center, low velocity near walls. Cells move rapidly through areas of low shear.

Ew, Math

• Cardiac output (blood/min) = Heart rate (beat/min) x Stroke volume (blood/beat)
• Ejection fraction = Stroke volume/End diastolic volume
• Mean arterial pressure = (2/3 x Diastolic BP) + (1/3 x Systolic BP) ≈ 93mmHg
• Compliance = change in volume/change in pressure
• Poiseulle Equation: Flow (Q) = πPr⁴/8ηl

Heart Basics

• Phases of the cardiac action potential:
  • Phase 0 (Depolarization): Voltage-gated Na⁺ channels open.
  • Phase 1 (Initial repolarization): Voltage-gated Na⁺ channels close, voltage-gated K⁺ channels begin to open.
  • Phase 2 (Plateau): Voltage-gated Ca²⁺ channels open, K⁺ efflux continues, myocytes contract.
  • Phase 3 (Rapid repolarization): Voltage-gated Ca²⁺ channels close, slow voltage-gated K⁺ channels open.
  • Phase 4 (Resting potential): High K⁺ permeability.
• Systole vs diastole, Isovolumteric contraction and relaxation, Electrical activity before mechanical activity.
• Systolic and diastolic heart failure (different graphs showing pressure/volume relationships)

Drugs

• ACE Inhibitors (-pril): Indications: Hypertension, heart failure, MI. ADRs: Hypotension, worsening kidney function, cough, angioedema. Contraindications: Allergy, pregnancy.

• ARBs (-sartan): Indications: Hypertension, heart failure, MI. ADRs: Hypotension, worsening kidney function, cough, angioedema. Contraindications: Allergy, pregnancy.

• MRA (Spironolactone/Eplerenone): Indications: Hypertension (supplement), ascites in cirrhosis. ADRs: Gynecomastia, hyperkalemia. Contraindications: Allergy, pregnancy.

• Digoxin: Mechanism: Inhibits Na+/K+ ATPase -> increased Ca²⁺ -> increased contractility. Indications: Atrial fibrillation (AF) (rate control). ADRs: Arrhythmias, emesis, nausea, visual or CNS problems.

• Nitrates: Mechanism: Increase cGMP, vasodilation (arterial, venous, coronary). Indications: MI, angina, coronary spasm, MI with PE. ADRs: Headache, hypotension, reflex tachycardia, withdrawal syndrome.

• Calcium Channel Blockers:

  • Dihydropyridines (-dipine): Mechanism: Vasodilators, decrease BP, vasodilate coronary arteries, no effect on contractility or SA node. Indications: Hypertension. ADRs: Headache, low BP, edema.
  • Non-dihydropyridines (Verapamil, Diltiazem): Mechanism: Vasodilators, less potent than dihydropyridines, decrease myocardial contractility & sinus rate (slow SA node), increase refractory period of AV node. Indications: Atrial fibrillation (AF), Supraventricular tachycardia (SVT). ADRs: Bradycardia, worsening CO, edema.

• Beta-Blockers: Classification (nonselective, cardioselective, 3rd generation). Indications (angina, MI, hypertension, HFrEF, AF). ADRs (bronchospasm, bradycardia, worsening HF). Contraindications (severe reactive airway disease).

• Cholinergic Neurons & Receptors (parasympathetic): Cholinergic neurons: all skeletal muscles, preganglionic neurons (including to the adrenal gland), postganglionic neurons, some neurons in brain. Cholinergic receptors: Nicotinic (skeletal muscles, brain ganglia), Muscarinic (PSNS postganglionic neuron targets, sweat glands, brain)..

• Anticholinesterase Inhibitors: Mechanism: Target both nicotinic and muscarinic receptors. Indications: Myasthenia gravis.

• Antimuscarinics (Atropine): Mechanism: Target muscarinic receptors only. Indications: Bradycardia antidote, Surgical anesthetic.

• Neuromuscular blockers: Mechanism: Target muscarinic receptors specific to the NMJ. Indications: Surgical anesthetic.

Heart Sounds

• Know the descriptions of each heart sound, including its location, timing, character, and associated conditions.

Aortic Stenosis/Regurgitation.

• Pathophysiology: High pressures causing LV hypertrophy and increased O2 demand.
• Signs: Crescendo-decrescendo systolic ejection murmur, pulsus parvus et tardus. Low S2.
• Symptoms: Syncope, angina, dyspnea, sudden onset severe dyspnea, pulmonary edema.
• Treatment: Valve replacement (bioprosthetic or mechanical).
• Aortic Regurgitation
  • High-pitched blowing decrescendo early diastolic murmur.
  • Widened pulse pressure.
  • S3 (sign of volume overload)

Mitral Stenosis/Regurgitation

• Mitral Stenosis
• Pathophysiology: Impaired flow from LA to LV
• Signs: Decrescendo diastolic murmur, Afib, Opening snap, Loud S1.
• Symptoms: Asymptomatic, or HF in years. LHF (PND, orthopnea). RHF (Edema, portal HTN).
• Tx: Beta blockers, anticoagulants, diuretics, Percutaneous mitral balloon valvuloplasty.
• Mitral Regurgitation
  • Decrescendo systolic murmur.
  • Maybe S3.
  • Afib in chronic.
  • LHF: PND, orthopnea.
  • RHF: Edema, portal HTN.
  • CO: Fatigue, dyspnea
  • Tx: Beta blockers, anticoagulants, diuretics. Surgical mitral valve repair.

Pericarditis, Constrictive Pericarditis, Pericardial Effusion, Tamponade

• Pericarditis • Inflammation of pericardium, often viral, could be post MI • Typical symptom: pleuritic chest pain, improves leaning forward • Signs: Pericardial friction rub, ECG changes (diffuse ST elevation, PR depression, or other patterns) • Workup: Echo to rule out pleural effusion, other tests
• Constrictive Pericarditis • Thickening and rigidity of pericardium, typically resulting from acute pericarditis. • Symptoms: Fluid overload, elevated JVP, Ascites, Peripheral edema, reduced cardiac output, exertional dyspnea. • Signs: Tachycardia, Pulsus paradoxus, Pericardial knock (sudden cessation of ventricular filling) • Workup: Echo (increased pericardial thickness, abnormal ventricular filling)
• Pericardial effusion: Too much pericardial fluid • Symptoms: Orthopnea, retrosternal pain and hypotension • Signs: Muffled heart sounds, distended neck veins, tachycardia, pulsus paradoxus, obstructive shock, cardiac arrest
• Pericardial Tamponade: A severe form of pericardial effusion where pressure on the heart is significantly increased.
• Workup : Echo, POCUS, CXR (increased silhouette).
• Treatment: Unstable: pericardiocentesis. Stable: conservative measures or pericardiocentesis.

Infective Endocarditis

• Pathophysiology and Symptoms: S. aureus most commonly, transient bacteremia on damaged valve causing colonization → platelets aggregate to form a biofilm. Constitutional symptoms(fever), Tricuspid regurgitation, heart failure.
• Workup: Duke's criteria (CBC, 3x blood cultures, urine culture, ECG, CXR, ECHO)
• Treatment: Antibiotics (typically IV vancomycin), some indications for surgery.

Tests for the Heart and Myocardial Infarction (MI)

• Risk Tiers (asym/low, moderate, high) related to testing.
• Stress tests: Treadmill, pharmacologic (persantine, adenosine, dobutamine).
• Pathophysiology: Plaque rupture with thrombus (STEMI - complete occlusion) or Non-occlusive (NSTEMI).
• Ischemic (Type 1), mismatch (Type 2).
  • Signs: EKG changes (ST elevation/depression) and other markers
  • Types: STEMI, NSTEMI.
• Management: Acute: Cardiac monitor, EKG, large-bore IVs, oxygen, ASA, nitroglycerin (SL), morphine. PCI (if appropriate). Otherwise, thrombolytics.
• Complications: Mitral regurgitation, Arrhythmias, pericarditis, mural/septal rupture and tamponade. Mural thrombus.

CABG (Coronary Artery Bypass Graft)

• Coronary artery order of importance: LAD > circumflex > RCA.
• Coronary artery occlusion order: Left main coronary stenosis, Left main equivalent, Triple vessel, Double vessel
• Procedures using internal thoracic artery, radial artery, saphenous vein.

Aneurysms

• True involve all three layers of vessel wall.
• Saccular (saclike) and Fusiform (bulging).
• Pseudo aneuyrsims = walled off.
• Indications for repair: size (infrarenal AAA ≥ 5.5 cm men, 5cm women). Rapid growth rate (> 1 cm/year).
• Thoracic (6-6.5 cm)
• Popliteal (3-4 cm MC).

Dissection

• Pathophysiology Blood leaks into vessel wall, creating a false lumen.
• Signs: Tearing chest pain radiating to the back.
• Treatment: Fixing the tear.

Vascular Pathology

• Generally asymptomatic
• Never regress
• Treatment is prophylactic to prevent complications.
• Complications often include
  • Rupture
  • Embolism
  • Thrombosis
• Screening with abdominal ultrasound in people at high risk.

Risk of Rupture Increases with Aneurysm Size... except for saccular (mycotic) & pseudoaneurysms. Management includes Aggressive anti-atherosclerotic management, Stenting, or graft (open repair).

Limb Ischemia

• Acute: Embolic (catastrophic, white leg, complete sensory loss, often from cardiac source) or Thrombotic (progressive, hx of claudication).
  • Symptoms: Asx, Pain, pulses are absent, paresthesia (decreased fine touch), pallor.
  • Tx: Anticoagulation, oxygen, IV hydration, analgesia, endovascular options.
• Chronic: Intermittent claudication (functional, distal → proximal, often) or Critical limb ischemia (limb threatening, pain at rest, tissue loss, gangrene).
  • Tx: Medical management (ABCDEs, antiplt, statins, BP), exercise, smoking cessation. Surgical bypass/percutaneous revascularization (for severe ischemia).

ECGs and Arrhythmias

• Location Matters: ECG leads correspond to specific areas of the heart.
• Rate: Calculate using number of large boxes between QRS complexes (300/box count) or counting QRS complexes over ten seconds and multiplying by 6.
  • Normal: 60-100 beats per minute.
  • Tachycardia:= >100 bpm
  • Bradycardia: < 60 bpm.
• Rhythm: Regular or irregular. Narrow or wide QRS complexes. Present P waves. Evidence of AV block or retrograde P waves (Junctional).

Determining Normal Heart Axis

• Based on the positive/negative nature of leads I and aVF on an ECG.

AV Block

• 1st degree: PR interval > 0.20 seconds.
• 2nd degree Type 1 (Wenckebach): PR interval progressively lengthens until a QRS is dropped.
• 2nd degree Type 2: PR constant, but some QRS are dropped randomly.
• 3rd degree (complete): AV dissocation, no relationship between P and QRS

Bundle Branch Blocks

• RBBB & LBBB. QRS is widened beyond 0.12 seconds. Characteristic EKG morphology in limb leads.

Cardiac Arrhythmias, Narrow & Broad QRS

• Tachycardia (narrow QRS): Sinus tachycardia (Sympathetic stimulation), Atrial fibrillation (multiple foci, irregular rhythm), Atrial flutter (single reentrant circuit, sawtooth pattern).
• Tachycardia (broad QRS): Ventricular tachycardia (Autonomic focus or re-entrant circuit in ventricles; regular rhythm), Supraventricular tachycardia (narrow QRS, often with abnormal P waves, irregular rhythm).
• Ventricular fibrillation: Disordered impulses, rapid irregular wide QRS.

Treatments for Bradycardia/Tachycardia

• Bradycardia: Atropine, isoproterenol, Temporary pacing, permanent pacemaker (chronic).
• Tachycardia
  • SVT: Vagal maneuvers, adenosine, verapamil, diltiazem, cardioversion, procainamide, ibutilide.
  • VT: Adenosine, lidocaine, procainamide, amiodarone, Cardioversion (often).
  • AF (Atrial Fibrillation): ASA, clopidogrel, apixaban, rivaroxaban, dabigatran, BB, CCB, Digoxin, DC cardioversion(<48hrs). General principles for all: Identify the type, assess stability, treat accordingly.

Heart Failure

• Chronic progressive disease where the heart can't meet the body's oxygen demands.
• Compensated: Asymptomatic, has compensatory responses (enlarged heart, increase HR)
• Decompensated: Symptomatic, requires treatment/hospitalization.
• Systolic (HFrEF) and Diastolic (HFpEF): Left-sided (low EF, enlarged ventricles), Right-sided (pulmonary hypertension, fluid back-up), Biventricular (both sides).
• Causes: Ischemic heart disease, Cardiomyopathy (primary or secondary), Valvular heart disease, hypertension.
• Symptoms: Fatigue, reduced exercise tolerance, dyspnea, orthopnea, PND, edema (peripheral/pulmonary), ascites, elevated JVP, hepatomegaly, anorexia, and GI distress.
• Diagnosis: Clinical history, PE, vital signs, weight, volume status, CXR, EKG, Lab studies (CBC, electrolytes, BNP), echocardiogram for ventricular function.
• Treatment with medications (digoxin, loop diuretics, ACEis, ARBs, ARNi, other inotropes...).

Cardiomyopathy (3 Major Types)

• Dilated: Ventricular chamber enlargement and systolic dysfunction with normal LV wall thickness (due to various causes-viral, genetic conditions, etc.)
• Hypertrophic: Thickening of the ventricular walls (often genetic causes) and can lead to dilation of mitral/tricuspid annuli.
• Restrictive: Large atria, high amyloid deposit (often presents with diastolic dysfunction).

Classification of Heart Failure (NYHA, ACC/AHA)

• The various clinical classifications of Heart failure based on Functional capacity.

Assessment of Heart Failure

• Clinical history and physical exam (vital signs, weight, volume status, CXR, ECG, BNP, echocardiogram, additional testing like exercise tests).

Treatment for Heart Failure

• Diuretics (loops, thiazides), inotropes (digoxin, milrinone/dobutamine), ACE/ARBs, beta-blockers, and MRA.
• Early to late stage management as well as hospitalizations.
• Consider other options like implantable cardioverter defibrillators or Ventricular assist devices in end-stage HF.

Hypertension (HTN)

• Treatment: Lowering blood pressure to reduce associated CV risk. This includes lifestyle changes (diet, exercise) and medications.
  • Appropriate Medications: Diuretics (thiazides), ACE inhibitors, ARBs, beta-blockers, DHP CCBs.
• Management: Lifestyle changes (weight loss, diet, exercise, stress reduction) and antihypertensive medications based on patient risk group (High/Moderate/Low-risk) associated with thresholds and targets.

Pediatric Heart Disease

• Fetal Circulation: Ductus venosus, ductus arteriosus, foramen ovale.
• Congenital Heart Disease: Categories of lesions based on shunt involvement and blood flow characteristics (acyanotic/pink, cyanotic/blue).
  • Valves lesions (bicuspid aorta, aortic stenosis/regurgitation, mitral stenosis/regurgitation)
• Pediatric Murmurs: Classification of heart murmurs in children, separating innocent murmurs from significant heart disease (e.g., ASD, VSD, etc.
• Kawasaki Disease: Acute, systemic vasculitis with coronary artery aneurysm risk.

Respiratory Week 1

• Lung Volumes: TLC, VC, IRV, EVR, RV, FRC are defined (and depicted diagrammatically to show their relationship).
• Pulmonary Function Tests (PFT): How they're conducted and the values measured (FEV1, FVC, FEV1/FVC ratio, TLC, RV, and DLCO). Use these tests to determine if a patient has obstructive, restrictive, or isolated diffusion abnormalities.
• Interpreting PFT Results: Obstructive, restrictive, and isolated defects.