cardiology2016 161-170

Correct answer:E This patient is exhibiting symptoms consistent with paroxysmal supraventricular tachycardia (PSVT), and adenosine is the drug of choice for the treatment of this arrhythmia. As the name implies. PSVT comes on suddenly and the focus of automaticity lies above the ventricles (i.e. in the tissues of the atria or AV node). It can frequently be dependent on a reentrant circuit. Adenosine is a very rapid acting drug with a half-life of only less than 10 seconds. It acts by slowing conduction through the AV node by hyperpolarizing the nodal pacemaker and conducting cells The side effects most frequently associated with adenosine are flushing, chest burning (due to bronchospasm), hypotension and high grade AV block. (Choice A) Amiodarone is a class III antiarrhythmic and is useful in both supraventricular (atrial, nodal, junctional) and ventricular tachyarrhythmia. This is one of the broadest spectrum antiarrhythmic drug available. It is also known for its side effect profile which includes photodermatitis, a blue/grey skin discoloration, pulmonary fibrosis, and either hyper- or hypothyroidism. (Choice B) Lidocaine is a class IB antiarrhythmic and overdose or toxicity with lidocaine most commonly causes neurologic symptoms. It is usually indicated for ventricular arrhythmias. (Choice C) Procainamide is a class IA antiarrhythmic and is commonly associated with drug-induced lupus syndrome. (Choice D) Verapamil is a class IV antiarrhythmic and is the most cardioselective of the calcium channel blockers. It is a potent negative inotrope and previously was the drug of choice for PSVT. However, this has been replaced by adenosine. Additionally, the most frequent adverse reactions noted with verapamil are constipation and gingival hyperplasia. (Choice F) Digoxin slows conduction through the AV node and is also a positive inotrope. Digoxin/Digitalis causes a well-characterized toxicity; symptoms include fatigue, blurry vision, changes in color perception, nausea and vomiting, diarrhea, abdominal pain, confusion, and delirium. Educational Objective: Adenosine is a rapidly acting antiarrhythmic used to quickly convert people out of PSVT (drug of choice). It is also rapidly cleared and has a half-life of only less than 10 seconds. It commonly causes chest burning (bronchospasm), flushing and high grade block as adverse reactions (remember, this is the drug used for chemical stress tests!)
A. Acetazolamide B. Furosemide C. Hydrochlorothiazide D. Mannitol E. Spironolactone F. Triamterene
A2
Correct answer:E Mineralocorticoid receptor antagonists (eg, spironolactone, eplerenone) prevent aldosterone from binding to its receptor in the distal renal tubules. This leads to increased sodium and water excretion while conserving potassium ions (potassium-sparing diuresis). These antagonists also block the deleterious effect of aldosterone on the heart, causing regression of myocardial fibrosis and improvement in ventricular remodeling。 Mineralocorticoid receptor antagonists reduce morbidity and improve survival in patients with congestive heart failure and decreased ejection fraction. Therefore, they are recommended in addition to standard heart failure therapy (ACE inhibitors and beta blockers). They should not be used in patients with hyperkalemia or renal failure. The most common side effects are hyperkalemia and gynecomastia (spironolactone » eplerenone). (Choices Af C, and F) Acetazolamide (carbonic anhydrase inhibitor), hydrochlorothiazide (thiazide diuretic), and triamterene (epithelial sodium channel blocker) have a variably lower diuretic effect compared to loop diuretics and are not as efficacious for treating heart failure symptoms. (Choice B) Furosemide is a loop diuretic frequently used for treatment of pulmonary congestion and fluid retention in heart failure patients. Although loop diuretics improve symptoms significantly, they do not provide survival benefit (ie, improved morbidity but not mortality) in these patients. (Choice D) Mannitol is an intravenous osmotic diuretic used primarily to lower intracranial pressure and treat acute glaucoma. It is not used to treat heart failure as It can cause an initial rise in extracellular fluid volume, exacerbating pulmonary congestion and peripheral fluid retention. Educational objective: Mineralocorticoid receptor antagonists (eg, spironolactone, eplerenone) improve survival in patients with congestive heart failure and reduced left ventricular ejection fraction. They should not be used in patients with hyperkalemia or renal failuold man with nonischemic cardiomyopathy comes to the office for follow-up. He recently was hospitalized for acute decompensated heart failure The patient's symptoms have improved with multidrug treatment, but he has persistent shortness of breath on mild exertion. He has a history of hypertension and hypercholesterolemia. Blood pressure is 115/70 mm Hg and pulse is 66/min. There is a third heart sound on heart auscultation and mild lower extremity pitting edema. A recent echocardiogram showed a left ventricular ejection fraction of 30%. Which of the following diuretics would most likely improve survival if added to this patient's current regimen?
cardiology2016 161-170
Q1
A 24-year-old male presents to the emergency department with sudden onset of palpitations He had an episode similar to this one year ago that resolved spontaneously. Rapid IV injection of a drug into this patient results in instantaneous resolution of the arrhythmia but is accompanied with transitory flushing, burning in the chest and shortness of breath. Which of the following drugs was used to treat this patient's condition? A. Amiodarone B. Lidocaine C. Procainamide D. Verapamil E. Adenosine F. Digoxin