CVT Pharmacology & Cardiac Medications Flashcards

Which class of antiarrhythmic drugs works primarily by blocking sodium channels to stabilize cardiac cell membranes?

Answer: Class I

Class I antiarrhythmics (e.g., lidocaine, flecainide) block fast sodium channels, slowing conduction velocity and stabilizing excitable membranes.

Adenosine is used in the clinical setting primarily to:

Answer: Terminate paroxysmal supraventricular tachycardia

Adenosine transiently blocks AV nodal conduction to terminate reentrant SVT, restoring sinus rhythm within seconds.

Which anticoagulant is most commonly used during cardiac catheterization to prevent thrombus formation?

Answer: Heparin

Unfractionated heparin is the standard anticoagulant for procedural anticoagulation during cardiac catheterization due to its rapid onset and reversibility.

Nitroglycerin relieves angina primarily by:

Answer: Reducing preload and afterload through venous and arterial dilation

Nitroglycerin is a nitrate that donates nitric oxide, causing smooth muscle relaxation, venodilation, and reduced preload, decreasing myocardial oxygen demand.

A patient receiving digoxin therapy develops nausea, visual disturbances, and bradycardia. The CVT should suspect:

Answer: Digoxin toxicity

Classic digoxin toxicity presents with GI symptoms, visual changes (yellow-green halos), and bradyarrhythmias due to enhanced vagal tone and decreased AV conduction.

Beta-blockers are contraindicated in patients with which of the following conditions?

Answer: Decompensated heart failure

Beta-blockers are contraindicated in acute decompensated heart failure because negative inotropy can worsen cardiac output and precipitate cardiogenic shock.