Question | Answer |
Name two calcium channel blockers that slow heart rate and decrease conractility? | Diltiazem
Verapamil |
What is the drug of choice to decrease oxygen demand? | Beta Blocker |
How does Ranolazine (non-dihydropyridine)work? | Improves efficiency of oxygen utilization |
What are three things Ranolazine does not do? | Decrease heart rate or blood pressure and reduce contractility |
What are the side effects of Ranolazine (non-dihydropyridine)? | Dizziness, headache, constipation, QT prolongation |
When taking Ranolazine what are some contraindications? | Do not use with antifungals, or grapefruit juice |
Ranolazine dosage
(non-dihydropyridine) | 500 mg BID initially
Can titrate to 1000mg BID
second or third line agent for angina |
What is drug of choice for acute angina? | Nitroglycerine |
What are nitrate side effects? | headache, hypotension (causes venous dilation than arterial), nausea/vomiting, dry mouth, **TOLERANCE** |
True or False, Ranolazine is a 3A4 substrate and grapefruit juice will cause an increase of buildup of this medication? | True |
After which dose of nitrate do you call 911? | Take first dose and wait 5 minutes, take second dose and wait 5 minutes, if still having CP after 10 minutes, take 3rd dose and call 911 |
What is brand name of Isosorbide mononitrate Extended Release? | Imdur |
How do you take Imdur? | This is a long acting nitrate, taken once a day in the morning. Runs out after 12-14 hours to give you that nitrate free interval. |
How do you take Isosorbide dinitrate? | Once in the morning and then in afternoon at least 7 hours apart, do not take evenly spaced to give you the nitrate free period needed. |
Use nitrates cautiously in patients with? | Glaucoma, severe anemia, hyperthyroidism, hypovolemia, hyperthyroidism |
What is the shelf life of nitroglycerine? | 6 months, it is sensitive to light and oxygen |
What is dosage for Isosorbide mononitrate? | 30-120mg once daily |
What is phase 4 of the cardiac action potential? | The reset phase, where Na-K-ATPase puts cations where they are supposed to be |
What happens in phase 0? | Na rushes into the cell and becomes very positive. |
What happens in phase 1 and 2? | Calcium rushes in and Potassium goes out of the cell, plateau phase |
What happens in phase 3? | Potassium continues to rush out of the cell and produces a hypernegative charge. |
Mechanism of antiarrhythmics: what phase decreases automaticity? | Phase 4 |
Mechanism of antiarrhythmics: what phase increases the refractory period? | Phase 2 and 3 |
Mechanism of antiarrhythmics: what phase slows conduction velocity? | Phase 0 |
Mechanism of antiarrhythmics: what phase limits reentry? | Phase 1,2,3,and 4 |
What is the resting phase of ion channels? | Closed but ready to go |
What is the active phase of ion channels? | Open |
What is the inactive phase of ion channels? | Closed and can't be opened |
Which medications affect the Na Channel? | Ia. Procainamide, quinidine
Ib. Lidocaine, mexilitine
Ic. Propafenone, flecainide |
Which medications affect the nodal channel? | Beta blockers (SA and AV node) |
Which medications affect the K channel? | Amiodarone, sotalol,... |
Which medications affect the nodal Ca Channel? | Calcium channel blockers |
Class Ia agents affect which two channels? | Na and K- slow down initial depolarization and lengthen phase 2 and 3 by slowing down K release |
Class Ib agents have? | Rapid on-off kinetics, have little effect on normal heart rate(work well on tachy arrhytmias in phase 0) |
Class Ic agents have? | Slow on-off kinetics result in greater effects on phase 0. More pronounced slowing of conduction. |
Class II and IV Beta and Calcium channel blockers slow which phase? | Phase 4, most specifically at the AV and SA nodes. |
Which medication effects K to increase refractory period, has beta blocker properties and decreases automaticity, and Na channel blockers to decrease repolarization. | Amiodarone |
Used for supraventricular and ventricular arrhythmias | Class Ia and Ic |
Used for ventricular arrythmias | Class Ib |
Used for supraventricular rate | Class II and IV |
How do high K levels effect digoxin? | Digoxin won't work as well. |
How do low K levels effect digoxin? | Digoxin levels can become toxic. |
What are toxicity signs of digoxin? | Nausea, vomiting, weakness, and altered mental status. May see green halos but not common. |
Which two drugs can be used with impaired cardiac function for rhythm control? | Amiodarone and Dofetilide |
When treating atrial fibrillation, which is more important: rate or rhythm control | Rate control |
What is the half life of amiodarone? | 7 weeks- requires loading dose for sooner steady state. |
Amiodarone pharmacodynamic drug interactions? | Beta blockers, Ca Channel blockers, digoxin, most other antiarrhythmics, and anything with QT prolongation. Additive effect of bradycardia. |
Amiodarone pharmacokinetic drug interactions? | Warfarin (increases INR levels), digoxin, cyclosporine, opiates, statins, phenothiazines, triptans, anti-epileptics. |
Adverse Drug reactions with chronic use of amiodarone | Pulmonary toxicity, pneumonitis, fibrosis, hepatoxicity, optic neuropathy/corneal deposits, hypo/hyperthyroid, peripheral neuropathy paresthesias, ataxia, weakness tremor, photosensitivity, skin discoloration, Stevens-Johnson, blood dyscrasias |
Important monitoring for amiodarone? | EKG and CXR, electrolytes (esp K and Mg)baseline TSH, LFT and PFTs, Visual exam 6-12 months. |
Half-life of amiodarone | 7 weeks long |