PHARM :/
This class III antiarrhythmic prolongs the action potential duration by blocking potassium channels and is notable for its long half-life and risk of pulmonary fibrosis and thyroid dysfunction.
What is amiodarone?
Amiodarone is a class III antiarrhythmic with K⁺ channel blockade that prolongs repolarization (QT interval). Its iodine content causes thyroid abnormalities; its lipophilicity contributes to a very long half-life and pulmonary toxicity.
This EKG finding represents atrial depolarization and is normally upright in leads I, II, and aVF.
What is the P wave?
P wave = atrial depolarization. Its morphology and axis help identify atrial enlargement or ectopic atrial rhythms.
This formula is used to calculate LDL cholesterol using total cholesterol, HDL cholesterol, and triglycerides. What is the formula?
What is the Friedewald formula?
The Friedewald formula estimates LDL-C as: LDL-C = Total Cholesterol – HDL-C – (Triglycerides / 5). It is commonly used in routine labs when triglycerides are <400 mg/dL.
A 60-year-old man with hyperlipidemia presents with angina. Coronary angiography shows plaques in the LAD. What is the pathophysiology of his condition?
What is atherosclerosis (plaque formation in large arteries)?
Endothelial injury → lipid deposition → inflammation → plaque formation. Plaques in coronary arteries reduce perfusion → angina.
This murmur has a diastolic opening snap
What is mitral stenosis
Opening snap: high frequency, early to middiastolic sound, heard after S2. Occurs when mitral leaflet motion suddenly stops during diastole because the stenosed valve has reached its maximum opening.
This subset of class I antiarrhythmics have an increased risk for torsades de pointes.
What is class IA?
Class IA antiarrhythmics have moderate blockade of sodium channels which prolongs the AP duration. They also have blockade of the potassium channels which prolongs the QT interval, increasing the risk of torsades.
An irregularly irregular rhythm with absent P waves and narrow QRS complexes is characteristic of this arrhythmia.
What is atrial fibrillation?
Atrial fibrillation = chaotic atrial electrical activity with no discernible P waves and an irregularly irregular ventricular response.
This apolipoprotein is found exclusively on chylomicrons, is required for secretion from enterocytes, and constitutes 48% of apo-B protein.
What is Apo-B48?
Apo-B48 is unique to chylomicrons, unlike Apo-B100 (found on VLDL, IDL, LDL). It is essential for chylomicron assembly and secretion.
A patient with chronic kidney disease has elevated blood pressure due to volume overload. Which mechanism contributes most?
What is impaired pressure natriuresis?
In CKD, the kidneys can’t excrete sodium effectively → volume expansion → hypertension.
This problem will have an absent a wave on a jugular venous pressure tracing
What is Afib?
Afib is characterized by chaotic, disorganized atrial electrical activity. The atrial kick (a wave) is lost because atrial contraction is absent or very ineffective.
This direct arteriolar vasodilator increases cGMP leading to smooth muscle relaxation, but can cause reflex tachycardia and lupus-like syndrome as adverse effects.
What is hydralazine?
Hydralazine increases cGMP to relax vascular smooth muscle (preferentially arterioles). It can cause reflex tachycardia, fluid retention, and drug-induced lupus (anti-histone antibodies).
ST-segment elevations in leads II, III, and aVF with reciprocal depression in leads I and aVL indicate infarction in this anatomic region of the heart.
What is an inferior wall myocardial infarction (RCA territory)?
Inferior MI = involves the right coronary artery (RCA). Look for ST elevation in II, III, aVF; reciprocal depression in I, aVL.
A patient presents with lipid deposits in their Achilles tendons and a milky corneal ring. This constellation of findings suggests a severe familial lipid disorder involving LDL receptor deficiency.
What is Familial Hypercholesterolemia (Type II)?
Type II familial hypercholesterolemia is autosomal dominant with few/absent LDL receptors. Tendon xanthomas and corneal arcus are hallmark findings.
A 62-year-old woman presents with crushing chest pain >30 minutes. ECG shows ST elevation in V2-V5. Troponins elevated. What is the diagnosis?
What is STEMI (anterolateral MI)?
ST elevation in contiguous leads indicates transmural ischemia. Troponin elevation confirms myocardial necrosis. Immediate reperfusion is required.
This embryologic structure gives rise to the coronary sinus.
What is the left horn of the sinus venosus?
The left horn of the sinus venosus becomes the oblique vein of the left atrium and the coronary sinus, which collects venous blood from the heart itself. The coronary sinus then drains into the right atrium near the tricuspid valve, providing the main venous return from the myocardium.
This lipid-lowering agent activates PPAR-α to increase lipoprotein lipase activity and decrease triglycerides, but may cause myopathy, especially when combined with statins.
What is a fibrate (e.g., gemfibrozil or fenofibrate)?
Fibrates (gemfibrozil, fenofibrate) activate PPAR-α, increasing LPL activity and fatty acid oxidation. Major side effects: myopathy (esp. with statins) and cholesterol gallstones.
A “bunny ears” pattern (RSR′) in V₁–V₂ with a widened QRS complex is characteristic of this conduction abnormality.
What is a right bundle branch block (RBBB)?
RBBB → delayed right ventricular depolarization → classic RSR′ pattern (“rabbit ears”) in V₁–V₂ and wide QRS (>120 ms).
When triglycerides exceed 1000 mg/dL, patients are at risk of this acute abdominal emergency due to capillary obstruction and free fatty acid-mediated tissue injury.
What is acute pancreatitis?
Severe hypertriglyceridemia → chylomicron accumulation → ischemia and free fatty acid-mediated injury → pancreatitis.
A 50-year-old man with history of amyloidosis has low-voltage ECG, biatrial enlargement on echo, and restrictive filling pattern. What cardiomyopathy does he have?
What is restrictive cardiomyopathy?
Non-dilated ventricles with stiff myocardium → diastolic dysfunction. Causes: amyloidosis, sarcoidosis, hemochromatosis.
This area of the heart is where you would listen if you were concerned for an ASD.
What is the pulmonic area (2nd IC space, left sternal border)?
In an ASD, blood flows left to right, increasing right heart volume. This increased flow across the pulmonic valve produces a mid-systolic ejection murmur. The murmur is not at the ASD itself; you will hear it where the blood flows faster which is over the pulmonic valve.
This β₁-selective blocker with additional α₁-blocking activity is especially useful in chronic heart failure due to its ability to decrease afterload and improve mortality.
What is carvedilol?
Carvedilol is a nonselective β and α₁ blocker that decreases afterload and improves LV function in chronic heart failure; reduces mortality in HFrEF (heart failure with reduced EF).
A progressively lengthening PR interval until a beat is dropped describes this type of AV block. What is Mobitz type I (Wenckebach) AV block?
What is Mobitz type I (Wenckebach) AV block?
Mobitz type I (Wenckebach) = progressive AV nodal delay until a nonconducted P wave (dropped QRS). Often benign, can be seen in athletes or due to increased vagal tone (second-degree AV block)
A patient has high total cholesterol and triglycerides, xanthomas, and a premature coronary event. Genotyping reveals Apo-E2 homozygosity. This patient most likely has this rare type of familial dyslipidemia.
What is Familial Dysbetalipoproteinemia (Type III)?
Type III is due to Apo-E2 subtype, causing impaired clearance of chylomicron remnants and VLDL. Presents with mixed hyperlipidemia and xanthomas.
A 55-year-old man has dyspnea and fatigue. ECG shows a constant PR interval but occasional dropped QRS complexes. What is the diagnosis?
What is Mobitz Type II AV block?
Mobitz II shows constant PR intervals with sudden non-conducted P waves. Often associated with bundle branch disease, high risk of progression to complete heart block → may need a pacemaker.
This factors makes hypertensive emergency different from hypertensive urgency.
What is end-organ damage?
Both are characterized by severe hypertension (greater than or equal to 180/greater than or equal to 120), by only hypertensive emergency has end-organ damage ex. encephalopathy, stroke, retinal hemorrhages and exudates, papilledema MI, HF, aortic dissection, kidney injury, MAHA, eclampsia).