Anti-anginal drugs Flashcards
drug therapy options for exertional angina
Nitrates Calcium Channel Blockers Beta Blockers Ranolazine Ivabradine
how do nitrates work in SMC
Activates Guanylyl Cyclase Increases cGMP Dephosphorylates Myosin Light Chains Ultimately Produces Smooth Muscle Relaxation Relaxation Is ENDOTHELIUM-INDEPENDENT
NITRATE MECHANISM OF ACTION
• DECREASED VENOUS RETURN Dilates Venous Capacitance Vessels • REDUCED LV WALL TENSION LaPlace’s Law • REDUCED AFTERLOAD • DIRECT CORONARY ARTERY VASODILATATION Increased Subendocardial Perfusion
CLINICAL USE OF ORGANIC NITRATES
Angina Pectoris Exertional Angina Unstable Angina Prinzmetal’s Angina Hypertensive Emergencies Congestive Heart Failure
MOST COMMONLY USED ORGANIC NITRATES FOR ANGINA
Nitroglycerine (sublingual, spray, patch or ointment)
Isosorbide mono/dinitrate (sublingual, chewable, oral)
nitrate side effects
orthostatic hypotension
reflex tachycardia
headache
nitrate tolerance (cannot be given 24/7)
what type of channel regulates smooth muscle contracton
voltage gated L-type Ca channels
what type of channel regulates cardiac muscle contration
voltage gated L-type Ca channels - in cardiac cells the amount of Ca that enters is proportional to the strength of contraction
what type of channel regulates cardiac pacemaker activity
L-type Ca channels
CLINICAL USE OF CALCIUM CHANNEL BLOCKERS (6)
Angina Pectoris Hypertension Arrhythmias Hypertrophic Cardiomyopathy Migraine Raynaud’s Phenomenon
CALCIUM CHANNEL BLOCKERS FOR ANGINA exampes
DIHYDROPYRIDINES
Nifedipine
Nicardipine
Amlodipine
VERAPAMIL
DILTIAZEM
BEPRIDIL
nifedipine has mainly what type of effect
vasodilatory (very little negative inotrophic and chronotropic effects)
side effects of Verapamil and diltiazem (CCB)
bradycardia
CHF
heart block
hypotension
side effects of nifedipine
reflex tachycardia
peripheral edema (a little usually means the drug is working and will go away)
hypotension
where are B1 and B2 receptors found?
β1 Receptors:
Cardiac Muscle
β2 Receptors:
Cardiac Muscle
Bronchial Smooth Muscle
Vascular Smooth Muscle
cAMP ACTIONS IN CARDIAC MUSCLE
• Increased Opening of L-type Ca channels Inotropy • Increased Reuptake of Ca into SR stores Inotropy & Lusitropy • Increased Pacemaker Current Chronotropy • Increased Rate of Conduction Dromotropy
B-blockers effects on the heart
block cAMP effects: • decrease HR • decrease afterload • increase heart size • decrease contractility • decrease O2 wastage * anti-arrhythmic • increased diastolic perfusion • decrease O2 demand
CLINICAL USE OF BETA BLOCKING AGENTS (8)
Angina Pectoris Hypertension Arrhythmias Dissecting Aortic Aneurysm Mitral Valve Prolapse Post-MI Prophylaxis Hyperthyroidism Migraine
NONSELECTIVE (BETA-1+BETA-2) BBs
PROPRANOLOL
NADOLOL
CARDIOSELECTIVE (BETA-1) BB
ATENOLOL
METOPROLOL
NONSELECTIVE WITH ISA
LABETALOL
PINDOLOL
CARDIOSELECTIVE WITH ISA
ACEBUTOLOL
BB primarily eliminated by the liver
Propranolol, Caredilol, Metoprolol
BB primarily eliminated by the kidney
Atenolol, Nadolol, Sotalol
BETA BLOCKER SIDE-EFFECTS
BRONCHOSPASM* (do not give if pt has obstructive pulmonary disease)
PERIPHERAL VASOSPASM
EXAGGERATION OF CARDIAC THERAPEUTIC EFFECTS
CNS EFFECTS
INSOMNIA
DEPRESSION
FATIGUE
CONTRAINDICATIONS TO ADMINISTRATION OF BETA BLOCKERS
Acute Congestive Heart Failure Marked bradycardia (HR
RANOLAZINE - suggested MOA
Ranolazine partially inhibits fatty acid oxidation, allowing the heart to use more glucose as a fuel by relieving the inhibition on pyruvate dehydrogenase.
The net result is reduced lactic acid accumulation, less intracellular acidosis, and a reduction in the severity of the myocardial ischemic response.
IVABRADINE MOA
Ivabradine is an If Current Inhibitor (The “funny” current) responsible for Phase IV depolarization of the SA node.
Inhibits pacemaker activity and slows the heart rate at rest and during exercise
who is Ivabradine recommended for?
Indicated for the symptomatic treatment of chronic stableangina pectoris in patients with normalsinus rhythmwho cannot take beta blockers.
Also indicated in combination with beta blockers in heart failure patients with LVEF lower than 35 percent inadequately controlled by beta blockers alone and whose heart rate exceeds 70 beats per minute.
how effective is ivabradine
As effective as beta blockers and comparable withamlodopine in the management of chronic stable angina
side effects of ivabradine
Luminous Phenomena; bradycardia, AV block
NONPHARMACOLOGICAL Rx OF ANGINA PECTORIS
Exercise Training Angioplasty Atherectomy Stents Intra-Aortic Balloon Counterpulsation Coronary Artery Bypass Grafting (CABG) ? Angiogenic Gene Therapy
