Angina Flashcards
Define angina pectoris
an imbalance btwn the oxygen requirement of the heart and the oxygen supplied to it via the coronary aa.
Define stable angina (effort; classic)
inadequate blood flow in the presence of CAD
Define variant angina (vasospastic, Prinzmetal)
transient spasm of localized portions of the vessels resulting in sig. myocardial ischemia and pain
Define unstable angina (acute coronary syndrome)
present when episodes of angina occur at rest and when these is an increase in the severity, freq. and duration of CP in pts with previously stable angina
What determines the oxygen requirement of the heart?
diastolic factors: blood volume, venous tone
systolic factors: peripheral resistance, HR, heart force, ejection time
Describe the typical presentation of stable ischemic heart disease
brought on by exercise
relieved by rest/sublingual Nitro
substernal CP: squeezing, heaviness, tightness lasting usually 5-10min
Radiation: L/R arm, back, abd, neck
Which drugs are used in Angina Pectoris?
Nitrates
Beta Blockers
Calcium Channel Blockers
Misc. (Ranolazine, Ivabradine)
Nitrates MOA?
Nitroglycerin
releases nitric oxide in smooth muscle which activates guanylyl cyclase and increase cGMP —> vascular smooth muscle relaxation
Effects of Nitroglycerin
Smooth muscle relaxation
vasodilation decreases VR and heart size
may increase coronary floq
Clinical application for Nitroglycerin?
Oral/Transdermal: Prophylaxis
IV: ACS
Sublingual: acute episodes of angina
Nitroglycerin PK?
high first pass effect, so sublingual dose is much smaller than oral
Side effects of Nitroglycerin?
orthostatic hypotension, tachycardia, HA
Nitroglycerin drug interactions
Phosphodiesterase type 5 inhibitors- synergistic hypotension
Long acting Nitrate? Ultrashort acting Nitrate?
Transdermal
Amyl nitrite (not really used)
BB MOA
blocks sympathetic effects on heart and blood pressure, reduces renin release
Effects of BB?
decreased HR , CO and BP
decreases myocardial oxygen demand
Clinical applications for BB in angina?
prophylaxis
BB toxicities?
asthma, AV block, acute HF, sedation
Name 3 CCBs. MOA?
Nondihydropyridine: Verapamil, Diltiazem
Dihydropyridine: Nifedipine
Nonselective block of L type calcium channels in vessels and heart
Effects of CCBs
reduce vascular resistance, HR, and cardiac force results in decreased oxygen demand
Clinical application for CCB?
prophylaxis of angina
HTN
Side effects of CCBs?
Non-dihydropyridine: AV block, acute HF, constipation, edema
Dihydropyridines: excessive hypotension, baroreceptor reflex tachycardia
What are good combo therapy options for pts with angina pectoris?
Nitrate/BB
Nitrate/CCB
depends on what is better tolerated
What kind of drug is Ranolazine? MOA?
Sodium channel blocker
inhibits late sodium current in heart
Effects of Ranolazine
reduces cardiac oxygen demand
fatty acid oxidation modification may improve efficacy of cardiac oxygen use
Clinical application for Ranolazine?
Prophylaxis of stable angina
Ranolazine toxicity?
QT interval prolongation
N, constipation, dizziness
Ranolazine drug interactions?
Inhibitors of CYP3A increase Ranolazine concentration and duration of action
Off label use of Ivabradine?
inhibits SA pacemaker–> reduction of HR reduces oxygen demand
What should you use to treat acute episodes of angina?
Sublingual or sprayed Nitroglycerin
relief of discomfort within 2-4 mins can be expected
What can you give to a pt with frequent anginal episodes?
BB such as Metoprolol
if intolerant= medium to long acting CCB i.e. Verapamil, Diltiazem or Amlodipine
