GPT 2.01 Notes Flashcards
(21 cards)
What are the key anatomical components of the cardiovascular system?
Heart chambers, valves, coronary arteries, conduction system (SA node, AV node, bundle branches, Purkinje fibers)
What are the cellular and molecular events in cardiac contraction?
Calcium influx triggers actin-myosin cross-bridge cycling in cardiac muscle cells
What is unique about cardiac muscle?
Striated, involuntary, interconnected by intercalated discs enabling synchronized contraction
How does the autonomic nervous system regulate heart rate?
Sympathetic increases rate and contractility; parasympathetic (vagus nerve) decreases heart rate
What are normal heart pressures and how do they relate to heart sounds?
Pressure rises cause valve opening/closing; S1 = AV valve closure, S2 = semilunar valve closure
What key features are seen on a normal ECG?
P wave (atrial depolarization), QRS complex (ventricular depolarization), T wave (ventricular repolarization)
What is atheroma pathogenesis?
Endothelial injury → lipid deposition → inflammation → plaque formation
What causes thromboembolism?
Thrombus formation on plaques or stasis → embolus breaks off → vessel occlusion
Define Coronary Heart Disease (CHD), Acute Coronary Syndrome (ACS), and Myocardial Infarction (MI).
CHD = narrowing of coronary arteries; ACS = sudden reduced blood flow; MI = myocardial necrosis from ischemia
What is the pathophysiology of CHD?
Atherosclerosis → reduced coronary blood flow → ischemia → angina or infarction
What are clinical features of CHD?
Chest pain, dyspnea, fatigue, possible MI symptoms
What are investigations for CHD?
ECG, cardiac enzymes (troponins), stress test, coronary angiography
What are management principles for CHD?
Lifestyle changes, antiplatelets, statins, nitrates, revascularization
What drugs are used in CHD and their mechanisms?
Aspirin (antiplatelet), statins (lipid lowering), beta-blockers (reduce O2 demand), nitrates (vasodilation)
How does CHD contribute to heart failure?
Ischemic damage weakens myocardium → impaired contractility and cardiac output
Define heart failure in terms of stroke volume, filling pressure, and contractility.
Reduced stroke volume due to impaired contractility or increased filling pressures (preload) per Starling’s Law
What is the pathophysiology of heart failure?
Systolic or diastolic dysfunction → inadequate tissue perfusion → compensatory mechanisms → symptoms
What are clinical features of heart failure?
Dyspnea, edema, fatigue, orthopnea, pulmonary congestion
What investigations are used in heart failure?
Echocardiogram, BNP levels, chest X-ray, ECG
What are management principles of heart failure?
Diuretics, ACE inhibitors, beta-blockers, lifestyle changes, device therapy
What is the pharmacology of drugs used in heart failure?
Diuretics reduce fluid overload; ACE inhibitors reduce afterload; beta-blockers reduce sympathetic stress; digoxin increases contractility
