drug therapy angina
Calcium Channel Blockers
uniquely effective for decreasing frequency/severity of spasm
dilate coronary arteries
decreases vascular smooth muscle tone, contractilty, O2 consumption, systemic BP
**not as effective as beta blockers in decreasing myocardial reinfarction
pathogenesis of STEMI
coroanry blood flow decreases abruptly
acute trombus formation d/t atherosclerotic plaque
thrombogenesis
*collagen, ADP, epinephrine, serotonin, TXA2, GP 2B/3A, fibrin deposit
imbalance of myocardial o2 supply and consumption caused by
atheromatous plaque
coagulation cascade
thrombin genreation
arterial occlusion (partial or complete)
drug therapy in ACS (6)
MONA
P2Y12 inhibitors
GP 2B/3A inhibitors
heparin
BB *relieves ischemic chest pain, infarct size, and dysrhytmias
RAAS inhibitors
*avoid gluccocorticoids and other NSAIDS in patients with STEMI
*restore blood flow in obstructed coronary artery ASAP
causes of unstable/NSTEMI
rupture or erosion if coronary plaque
*thrombosis
dynamic obstruction due to vasoconstriction
*prinzmetal- variant angina, cold, cocaine use
worsening coronary luminal narrowing due to progressive atherosclerosis, in -stent restonosis, narrowing of CABGs
inflammation (vasculitis)
myocardial ischemia due to increased O2 demand
*sepsis, fever, tachycardia, anemia
ACE inhibitors
treats HTN, heart failure, cardioprotective
prevents ventricular remodeling, stabilizes electrical acitivity of re-perfused heart and prevent occurance of reperfusion arryhtmias
reduce myocardial workload and decrease myocardial O2 demand
defining diagnosis of Myocardial infarction
rise or fall of cardiac markers (troponin) AND at least
* symptoms of ischemia
* ECG changes (ST changes, new LBBB)
* Q waves on ECG
* imaging evidence of new loss of vialable myocardium or new regional wall abnormality
*angiography identifying intracoronary thrombus
no ST segment elevation
positive troponins
NSTEM -> myocardial infarction
reperfusion therapy
thrombolytic therapy with tPA , streptokinase, within 30-60 minutes of hospital arrival and within 12 hrs of symptoms onset
*restores antegrade blood flow in occluded coronary artery
presentation
angina at rest lasting > 10 minutes
chronic angina pectoris - a crescendo pattern - increasing in intensitiy, duration, frequency
new-onset angina that is severe, prolonged, or disabling
statins
coronary plaque stabilization
decreases lipid oxidatoin, inflammation, matrix metalloproteinase, cell death
reduces mortality of noncardiac surgery and vascualr surgery
troponin
increase within 3 hours after myocardial injury
remain elevated for 7-10 days
*more specific than CK-MB
*the greater the level of troponin the larger the MI
no ST elevation
negative troponins
unstable angina
PCI
indications
treatment
severe HF and/or pulmonary edema
symptoms present for 2-3 hours
mature clot (less likely to be lysed by fibrinolytic)
contraindications to thrombolytic therapy
*coronary stents and antiplatelet drugs
treatment of NSTEMi
bed rest, O2, analgesia, BB therapy, subligual or IV nitro, CCB, ASA, P2Y12 inhibitors, heparin
thrombolytic therapy not indicated
revascularization
indicated for failure of medical therapy
>50% occlusion of L main coronary
>70% stenosis of epicardial coronary artery
imparied EF < 40%
imaging studies
patients with a typical ECG evidence of AMI do not need an echo
useful in patients with LBBBB or abnormal ECG in whom AMI is uncertain
regional wall motion abnormalities in most patietns with AMI
ST segment elevation
positve troponins
STEMI -> myocardial infarction
restore blood flow in occluded coronary artery
emergent CABG - indicated anatomy that inhibtis PCI, failed angioplasty, evidence of infarction related ventricular septal rupture or mitral regurgitation
CABG > PCI
CABG is preferred over PCI in patients with significant left main coronary artery disease
- 3 vessel CAD
-DM with 2-3 vessel CAD
DAPT (dual - antiplatelet therapy)
ASA with P2Y12 inhibitor
minimum 2 weeks - balloon angioplasty without stenting
minimum 6 weeks - bare metal stent
mimimum 1 year - drug - eluting stent
surgery interval
time to wait for elective surgery
*balloon angioplasty no stent 2-4 weeks
*bare-metal stent: 30 days to 12 weeks
*CABG: 6 weeks - 12 weeks
*drug eluding stent: 6 months - 12 months
neuraxial is not encourgaged in patietns who are receiving DAPT
PCI
alternative to CABG
balloon angioplasty, bare metal stent, drug - eluding stent
angioplasty may cause vessel injurt - destruction of endothelium making areas prone to thrombosis
risks - bleeding, thrombosis