Angina Flashcards
Types of Angina (3)
1 atherosclerotic
2 vasospastic
3 unstable
Determinants of cardiac oxygen requirement (2)
1 Diastolic factors
2 Systolic factors
both lead to cardiac fiber tension
Inc myocardial O2 req
Diastolic factors (2)
Blood volume
Venous tone
Systolic factors (4)
Peripheral resistance
Heart rate
Heart force
Ejection time
Goals for angina management(4)
Inc O2 delivery
Reduce O2 req
Inc efficiency of O2 utilization
Myocardial revasc
Releases nitric oxide in smooth muscle cells through mitochondrial enzyme aldehyde dehydrogenase 2 ALDH2
Nitrates
Given SL, transdermal, IV, oral
High first pass effect
Nitroglycerin
Nitrate given orally
Isosorbide mononitrate
Nitrate given SL, orally
Isosorbide dinitrate
Nitrate inhaled
Amyl nitrite
Activates nitrite to nitric oxide by ALDH2/3
NO combines with guanylyl cyclase Inc CGMP PGE prostaglandin production PGI prostacyclin production Diminished vascular smooth muscle activation Vasodilation of arteries and veins
Nitrates
Nitrate tolerance attributed to (3)
Sulfhydryl group - cysteine
Inc O2 free radicals
Dec calcium generated polypeptide cgrp (vasodilator)
Nitrates relieve angina by
Inc venous compliance Dec ventricular preload Relaxation of veins Dec CO promote diastole inc CBF Relaxation of bronchi GI Inc CGMP Dec platelet aggregation
Nitrate SE
OH
syncope
headache
Temporal pulsation
Nitrates CI in
Inc ICP
IF TOLERATING GIVE CYSTEINE
Nitrates cause
compensatory tachycardia, contractility and salt and water retention
Nitrate uses
Angina
Cyanide poisoning
Nitrates can promote lethal hypotension if combined with
PDE5 inhibitors
Sildenafil
MI
Nitrates cause toxicity of
Methemoglobinemia
Alpha 1 recetor affinity with more effect on smooth muscle vs nondihydropiridine bec of K channel
Nifedipine
Dec transmembrane Ca current leading to
relaxation of vascular, bronchial, GI and uterine smooth muscles
dec in cardiac contractility
dec in SA node/AV node (hr)
Ca ch blocker L type
Ca ch blockers reduce BP but induce
Reflex tachycardia (Nifedipine)
Dec heart rate and contractility
Blocks calcium dependent conduction in AV node
Non Dihydro Ca ch blocker
Used as prophylaxis for effort and vasospastic angina HTN SVT Migraine Preterm labor Stroke/SAH Raynaud’s
Calcium ch blocker
Ca ch blocker SE (4)
AV block nondihydropiridine MI (short acting Nifed) Constipation Bradycardia Pretibial edema Flushing Dizziness
Dec cardiac workload (BP, HR, contractility)
Dec O2 demand (reduced ischemic time)
Inc heart size
Prolonged ejection
Beta blockers
Beta blockers inc EDV and ejection time so they are best balanced by
nitrates due to inc O2 req
Prophylactic tx of exercise induced angina
Dec mortality in px with recent MI
Improves survival with stroke and HTN
Beta blockers
Beta blocker SE (4)
Erectile dysfunction
Hypoglycemia
Worsening claudication
Fatigue, insomnia
Avoid in asthmatics, bradycardics
Reduces late sodium current INa that facilitates Ca entry via Na-Ca exchanger dec intracell Ca and prolonging QT interval
Ranolazine
Dec diastolic tension cardiac contractility and work
Ranolazine
Ranolazine SE
Prolonged QT interval (CAD)
Shortened QT in long QT syndrome
Nicotinamide nitrate ester
Dec preload and afterload
Myocardial protective by activating cardiac K ATP ch
Nicorandil
Inhibits fatty acid oxidation in myocardium
PostMI and angina
Drug class
Trimetazidine
PFOX inhibitor
How is trimetazidine able to improve metabolic status of ischemic tissue
By partial inhibition of enzyme long chain 3 ketoacetyl thiolase LC-3KAT
Inhibits xanthine oxidase contributing to oxidative stress and endothelial dysfunction
Allopurinol
High dose allopurinol prolongs the
Exercise time in px with angina
Relatively selective If funny Na ch inhibitor
Reduces HR by inhibiting hyperpolarization activated Na ch in SA node but not in afib
Ivabradine
Reduces angina with efficacy similar to Ca ch blocker and Beta blocker
Ivabradine
Inhibitor of smooth muscle Rho kinase
Fasudil
Family of enzyme inhibiting vascular relaxation
Rho kinase (ROCK)
Reduces coronary spasm in experimental animals
Fasudil
CAD Medical Therapy (7)
Antiplatelet Lipid lowering ACEI Beta blocker Nitrate Ca ch blocker Anticoagulation
Intermittent claudication pain occuring in skeletal ms legs during exercise and disappears with rest
Chronic ischemic ulcers
PAD
PDE3 Inhibitor, selective antiplatelet and vasodilator for PAD
Inc exercise tolerance in pxs with severe claudication
Cilostazol
Xanthine derivative reducing viscosity of blood and inc deformability of RBC allowing efficient blood flow in obstructed areas
Pentoxyfylline
Determinants of vascular tone (4)
1 Inc CGMP (dephosphorylation of MLC NO)
2 Dec intracellular Ca (vasodilation, Ca ch blocker Beta blocker)
3 Inc K efflux permeability (opening of K ch prevents depolarization, Minoxil, Diazoxide)
4 Inc CAMP vascular smooth muscle inactivates MLCK(Beta 2 agonist, Fenoldopan D1)
Inhibits beta oxidation of FFA
Cytoprotective that normalizes blood flow in low flow ischemia
Trimetazidine
