Term
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Definition
Syndrome of acute myocardial ischemia.
Requires urgent treatment. Hospitalization. |
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Term
| spectrum of myocardial damage |
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Definition
| stable angina -> unstable angine -> "heart attack"- STEMI, NSTEMI |
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Term
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Definition
• TYPE 1 Primary Coronary Event (Plaque Rupture, Thrombotic Event) (often concerned about)
• Type 2 Supply Demand Mismatch
• Type 3 MI resulting in SCD (sudden cardiac death- ventricular fibrillation or ventricular tachycardia for ex)
• Type 4a MI associated with PCI
• Type 4b MI associated with stent thrombosis
• Type 5 MI associated with CABG |
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Term
| epidemiology of acute coronary syndrome |
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Definition
• Approx 800,000 US cases of ACS, annually.
• ACS : Median age 68 • Male : Female 3:2 |
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Term
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Definition
• Age (men>45, women >55) • Dyslipidemia
• Smoking
• HTN
• Diabetes • Obesity • Inactivity • Heredity |
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Term
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Definition
• STEMI rates are declining.
• Non-ST segment ACS rates are rising. |
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Term
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Definition
• O2 demand supply mismatch :
• Flow disruption.
• Coronary stenosis a/w plaque rupture/erosion +/- superimposed non- occlusive thrombosis.
• Coronary spasm.
• Coronary dissection. |
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Term
| plaque erosion vs plaque rupture findings |
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Definition
[image]
• Histology study: Most ruptured plaque in >75% stenosis
• Plaque rupture + mild stenosis: unlikely to occlude vessel. |
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Term
| plaque and events in ACS, precursor? |
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Definition
• Not all plaque rupture leads to events.
• Multiple ruptured plaques can be found in ACS!
• Precursor to plaque rupture: Thin cap fibroatheroma (TCFA).
• TCFA: Large lipid content with overlying thin fibrous cap.
• OCT/IVUS Study in ACS showed fibrous cap thickness <54μm a/w rupture. |
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Term
| plaque rupture and sudden cardiac death, prospect trial, acs |
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Definition
• Plaque rupture responsible for 2/3 of ACS
and sudden cardiac death.
• PROSPECT Trial: Event-related TCFA rupture a/w:
inc plaque burden dec lumen area |
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Term
| signs and symptoms of acs |
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Definition
• Chest pain or pressure
• Sweating
• Dyspnea
• Nausea, vomiting
• Dizziness or sudden weakness
• Fatigue
• Pain or pressure in the back, neck, jaw, abdomen, or shoulders or arms
• Symptoms that occur at rest; become more frequent, severe, or prolonged; do not respond to rest or nitroglycerin
• Flu-like symptoms
• Tachycardia or bradycardia
• Rales |
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Term
| separating out acs diagram |
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Definition
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Term
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Definition
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Term
| Einthoven's Triangle picture |
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Definition
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Term
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Definition
So we have then our 12-lead EKG. It is a 10-second snapshot of what's going on in the heart from left to right. And what you see on the left are the leads one, three, and aVF on the very left-- which are here. And next, the computer snaps and starts to record aVR, aVL, and aVF for a short period of time before switching to the precordial leads-- V1 through V6.
Often you will see on an EKG that lead two is repeated at the bottom continuously for the entire 10 seconds. And this gives you a rhythm strip and gives you a better chance to analyze the rhythm of the patient. |
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Term
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Definition
One of the commonest questions that students often ask is why there tends to be an ST segment depression with ischemia but ST segment elevation with infarction. This is actually a very interesting and tough question. And I've heard various answers to this. And I think that the best answer that I have heard is the following.
If you look at the heart on the left, this is a patient with subendocardial ischemia, or an NSTEMI in this setting. If there is subendocardial ischemia, as you see here on the left in this area, the positive voltage has a tendency to go from healthy areas into the ischemic area. And as it does so, it's going to move away from where your EKG lead has been placed-- in this case, here. So if the positive voltage is moving away from you, you're going to see negativity and downward deflection, which is what you see with ST depression here.
On the other hand, if there is an ST elevation MI-- if there is complete infarction of the muscle-- then the positive voltage is moving from other areas towards this area. So it's really in effect moving towards you. And therefore you see an ST elevation MI, better shown above. Here's an ST depression for ischemia and ST elevation. It is not always a satisfactory explanation, but one of the best that I've heard so far. |
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Term
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Definition
Here is a 12-lead EKG of a patient with chest pain. And in this case, they are having ST segment elevations in some of the leads. And if you look closely, you'll be able to appreciate which leads those are. In this case, there is a subtle ST elevation in leads V1, V2, V3, V4, and V5. And there are reciprocal depressions over here in lead three and aVF. There is actually an elevation in lead aVL and one as well.
This patient is having a large anterolateral infarct. You can also appreciate that the R waves have disappeared in these precordial leads-- V2 and V3-- and they've become Q waves. This patient is having an anterolateral infarct. |
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Term
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Definition
| Here's another EKG of another patient with an ST elevation MI. In this case, you will see elevations in leads two, three, and aVF. These are the leads that look at the underside of the heart. This is an inferior ST elevation MI. And it's typical of an RCA occlusion, typically. |
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Term
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Definition
| Here's another example where the elevations are seen in the inferior leads-- two, three, and aVF. But you also see evidence of elevations in leads V5 and V6. And you get what are called reciprocal depressions in some of the precordial leads, such as V2 and V3. And the R wave in V2 is larger than usual. This is what is sometimes called an inferoposterior infarct, or a cicumflex artery infarct. |
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Term
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Definition
This is what is sometimes called an inferoposterior infarct, or a cicumflex artery infarct.
Here's another example of a similar infarct, perhaps a little clearer. You can see elevations in leads two, three, and aVF, as well as changes elevations in V5 and V6 and reciprocal changes in V2, V3. This is another patient with what appears to be a circumflex artery infarct. All of these patients need to be treated emergently. |
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Term
| differating unstable angina UA from NSTEMI |
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Definition
| So how do we then differentiate unstable angina from NSTEMI? Well, the answer is in the name, because NSTEMI in an infarct. And the answer is the EKGs may look very similar-- there may not be any depression. But the cardiac biomarkers will be abnormal. And the answer is really anybody who has a troponin in the upper limits of normal, or what we call above the 99th percentile of the upper limit of normal. |
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Term
| treatment of acs components |
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Definition
| antiplatelet, anti-ischemic, antithrombotic, invasive strategy |
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Term
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Definition
| cardiac death, subsequent MI and cardiovascular death |
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Term
| risk stratification NSTE-ACS |
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Definition
| TIMI risk score, GRACE, PURSUIT |
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Term
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Definition
• Age ≥65 years
• 3+ risk factors for CAD: (FH of CAD, HTN, hyperchol, DM, tobacco use)
• Known CAD (stenosis >50%)
• Aspirin use, past 7 days
• Severe angina (≥2 episodes in 24 hours)
• ST deviation ≥0.5 mm
• Elevated cardiac marker |
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Term
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Definition
• Aspirin: Improved survival in ACS
• Clopidogrel • Prasugrel (Thienopyridine, P2Y12 inhibitor)
• Ticagrelor (Non-Thienopyridine, P2Y12 inhibitor) |
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Term
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Definition
= “Dual Antiplatelet Therapy”
ASA +
Clopidogrel / ticagrelor / prasugrel |
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Term
| B-blockers study findings |
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Definition
• COMMIT Trial (mostly STEMI): early IV followed by PO metoprolol.
• No sig difference in early mortality.
• Early metoprolol prevented a few cases of reinfarction or VF; led to more cardiogenic shock. |
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Term
| B-blockers: Current NSTE-ACS Guidelines by ACC/AHA: |
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Definition
• Oral beta-blocker therapy should be initiated within the first 24 hours in patients who do not have any of:
• 1) signs of heart failure
• 2) evidence of low-output state
• 3) increased risk for cardiogenic shock
• 4) other contraindications to beta blockade (eg, PR interval >0.24 second, second- or third degree
heart block without a cardiac pacemaker, active asthma, or reactive airway disease). |
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Term
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Definition
• Heparin ↑anti-thrombin → ⇣IIa, IXa, Xa.
• ⇣Thrombus propagation.
• Meta-analysis: UFH in NSTE-ACS: ↓ early ischemic events by 33-56%.
• Enoxaparin (LMWH) → ⇣Xa
• SQ administration, no need to “monitor” anti-coagulation, longer acting. |
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Term
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Definition
• ⇣ Platelet aggregation.
• Reduced ischemic events when added to
ASA+ heparin in ACS.
• Most favorable studies in pre-DAPT era!
• Early ACS Trial: No benefit over DAPT+heparin, more bleeding. |
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Term
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Definition
• DANAMI I & II
• Compared to thrombolysis, coronary angioplasty in MI led to:
• Better vessel patency, better LVEF, less myocardial ischemia.
• Less reinfarction.
• Angioplasty must be done within 2 hrs. |
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Term
| In UA/NSTEMI, invasive strategy, when compared with medical therapy: |
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Definition
• ↓ Rehospitalization, refractory angina. • ↓ MI, long term.
-haziness on coronary angiography is a clot, insert stent |
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Term
| differential diagnosis for chest pain |
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Definition
-aortic dissection (tearing pain radiating to back, neurologic symptoms, new murmur, bruits, unequal pulses. CXR, ct angiograph, echo)
-acute coronary syndrome (pressure-like pain w radiation to arms/face, diaphoresis, dyspnea, risk factors. may have evidence of heart failure. ecg, biochem markers)
-pulmonary embolism (sudden onset, pleuritic, dyspnea, risks for venous thrombosis. tachypnea, tachycardia, venous thrombosis. CXR, V/Q scan, CT angiogram or pulmonary angiogram)
-pneumothorax (pleuritis pain and syspnea. diminished breath sounds over hemithorax. CXR)
-could also be esopahgeal rupture, pneumonia, pericarditis, GI causes, Musculoskeletal causes |
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Term
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Definition
• Cardiogenic shock in ~7% of STEMI (<3% of NSTEMI)
• Defn: SBP<90, Cardiac index <1.8 L/min/m2, LVEDP (wedge) pressure >18mmHg
• End-organ malperfusion.
• Cool extremities, low urine output, altered mental status.
• Higher mortality. |
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Term
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Definition
• Inotropes.
• Intra-aortic balloon pump.
• Impella assist device. |
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Term
| Medicine adherence post-MI |
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Definition
improves clinical outcomes and cost
• 80% adherence to meds associated with best outcome.
• Statins, dual anti-platelet therapy, ACEi/ARB, Beta-blockers. |
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Term
| Summary & Conclusions for ACS |
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Definition
• ACS is a spectrum of coronary ischemic emergencies.
• Myocardial infarction is a type of ACS.
• O2 supply-demand mismatch.
• History, exam, ECG, cardiac enzymes.
• ECG can show STEMI (vs not).
• Tx: Often all of: anti-platelet, anti- ischemic, anti-thrombotic, invasive. |
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