CARDIAC LECTURE KEY VOCABULARY

50 vocabulary flashcards covering anatomy, physiology, diagnostics, diseases, and treatments from the cardiac lecture notes.

Mediastinum

Central thoracic cavity space where the heart is located.

Pericardial sac

Double-layered membrane enclosing the heart and containing fluid for lubrication.

Preload

Filling pressure/stretch of the ventricles at end-diastole before contraction.

Afterload

Resistance the heart must overcome to eject blood during systole.

Contractility

Intrinsic strength of cardiac muscle contraction independent of preload and afterload.

Cardiac output

Volume of blood pumped by the heart per minute (HR × stroke volume).

Stroke volume

Amount of blood ejected by one ventricle with each heartbeat.

Pulse pressure

Difference between systolic and diastolic blood pressure; normally about one-third of SBP.

Mean Arterial Pressure (MAP)

Average arterial pressure felt by organs; calculated (SBP + 2DBP)/3; ≥60 mm Hg needed for perfusion.

Sinoatrial (SA) node

Primary pacemaker of the heart located in right atrium; initiates electrical impulse.

Atrioventricular (AV) node

Electrical gateway between atria and ventricles; delays impulse before ventricular conduction.

Bundle of His

Specialized conducting fibers that transmit impulses from AV node to bundle branches.

Purkinje fibers

Network of fibers distributing electrical impulse through ventricular myocardium for contraction.

P wave

ECG deflection representing atrial depolarization.

QRS complex

ECG waveform representing ventricular depolarization.

QT interval

Time from ventricular depolarization to repolarization on ECG; varies with heart rate.

PR interval

ECG measurement from onset of P wave to start of QRS; reflects AV conduction time.

Coronary circulation

Network of arteries and veins that supply blood to and drain blood from the myocardium.

Right Coronary Artery (RCA)

Coronary vessel supplying right atrium, right ventricle, SA and AV nodes, inferior LV.

Left Anterior Descending artery (LAD)

Branch of left coronary artery supplying anterior LV wall, septum, and apex.

Circumflex artery

Left coronary branch supplying lateral and posterior walls of left ventricle.

Cardiac biomarkers

Blood proteins released with myocardial injury, used to diagnose acute coronary syndromes.

Troponin I

Highly sensitive cardiac biomarker that rises within hours and peaks 10–24 h after MI.

Creatine Kinase-MB (CK-MB)

Cardiac-specific enzyme fraction that rises 3–6 h after MI; peaks around 18 h.

B-type natriuretic peptide (BNP)

Hormone released from ventricles in heart failure; indicates ventricular stretch and fluid overload.

Atherosclerosis

Plaque buildup in arterial intima leading to narrowing and reduced blood flow.

Arteriosclerosis

General term for thickening and loss of elasticity of arterial walls.

Coronary Artery Disease (CAD)

Atherosclerotic disease of coronary arteries leading to angina, MI, and death.

Hypertension

Persistent elevation of systemic arterial blood pressure.

Primary (essential) hypertension

Chronic high BP without identifiable cause; 90–95 % of cases.

Secondary hypertension

Elevated BP due to specific, correctable cause (e.g., renal disease, endocrine disorder).

Orthostatic hypotension

Drop in SBP ≥20 mm Hg or DBP ≥10 mm Hg with position change plus ↑HR or dizziness.

Hypertensive crisis

Acute severe elevation in BP (≥180/120 mm Hg).

Hypertensive emergency

Hypertensive crisis with evidence of acute target-organ damage requiring IV therapy.

Hypertensive urgency

Severe BP elevation without target-organ damage; treated with oral agents.

DASH diet

Dietary Approaches to Stop Hypertension; emphasizes fruits, vegetables, low-fat dairy, low sodium.

Cardiac catheterization

Invasive imaging of heart chambers and vessels using catheters and contrast dye.

Percutaneous Coronary Intervention (PCI)

Non-surgical procedure (e.g., angioplasty) to open narrowed coronary arteries.

Coronary artery stent

Expandable mesh tube placed during PCI to keep coronary artery open.

Coronary Artery Bypass Graft (CABG)

Surgical rerouting of blood around blocked coronary arteries using graft vessels.

Stable angina

Predictable chest pain with exertion relieved by rest or nitroglycerin.

Prinzmetal’s (variant) angina

Coronary artery spasm causing chest pain, often at rest and cyclically.

Acute Coronary Syndrome (ACS)

Spectrum of prolonged myocardial ischemia: unstable angina, NSTEMI, or STEMI.

Non-ST Elevation Myocardial Infarction (NSTEMI)

MI without ST elevation; partial coronary artery occlusion and elevated biomarkers.

ST-Elevation Myocardial Infarction (STEMI)

MI with ST elevation due to complete coronary occlusion; requires rapid reperfusion.

Collateral circulation

Alternate blood flow channels that develop around blocked coronary vessels.

Left Ventricular Hypertrophy (LVH)

Thickening of LV wall from chronic pressure overload (e.g., hypertension).

Cardiogenic shock

Severe pump failure after MI leading to inadequate tissue perfusion and high mortality.

Target organ damage

Structural or functional injury to heart, brain, kidneys, eyes, or vessels from hypertension.

Ambulatory Blood Pressure Monitoring (ABPM)

24-hour automated BP recording to confirm hypertension and detect white-coat effect.