Info

ASA. Clopidogrel ASA, Clopidogrel «upstroam o» at tmo ot PCO

ENOX. UFH, or londa UFH, ENOX. or txval (dopqndno on prei ol cath Ub>

prior CABG t

GP llb/llla inhibitor (upstroam Of al tim« o' PCH

CONS strategy INV strategy

M Angiography once stabilized and before d/c

J large pertvsvc Meet lesfXK ant) N. I

Medical Rx Long-term medical R*

Prinzmetal's (variant) angina

• Coronary spasm -»transient STE usually w/o Ml (but Ml, AVB, VT can occur)

• Pts usually young, smokers. • other vasospastic disorders (eg. migraines. Raynaud's)

• Tends to occur in morning; precipitated by hyperventilation or cold, not exertion

• Angiography nonobstructive CAD. focal spasm wI hyperventilation, acetylcholine

• Treatment: high-dose CCB, nitrates (+SL NTG prn), ? «-blockers; d/c smoking

• Cocaine-induced vasospasm: avoid |iB as unopposed «-stimulation can worsen spasm

Cocaine also associated with premature atherosclerosis (ne]m 2001:345:351)

STEMI

Fibrinolysis

• Indications: sx <12 h and either STE 2O.I mV (;:1 mm) in ¿2 contig. leads or LBBB not known to be old; benefit if sx >12 h less clear; reasonable if persistent sx & STE

• Door-to-needle time should be ^30 mins

• -20% 1 in mortality in anterior Ml or LBBB; 10% I in mortality in IMI

• Prehospital lysis: further 17% i in mortality tfAAW 2000:283:2686)

• 1% risk of ICH; high-risk groups include elderly ( 2% if >75 y). women, low wt

• Although age not contraindic.. t risk of ICH in elderly ( -75 y) makes PCI more attractive

• Fibrin-specific lytic (front-loaded TPA) 14% i mort. c/w SK (1% abs A; GUSTO, nejm

1993:329:673) although T ICH (0.7% vs. 0.5%); 3rd gen. bolus lyrics easier to administer, but no more efficacious

Contraindications to Fibrinolysis

Absolute Contraindications

• Intracranial neoplasm, aneurysm. AVM

• Nonhemorrhagic stroke or closed head trauma w/in 3 mo

• Active internal bleeding or known bleeding diathesis

• Suspected aortic dissection

Relative Contraindications

• Hx of severe HTN or SBP 180 or DBP »110 on presentation (? absolute contra, if low-risk Ml)

• Ischemic stroke >3 mos prior

• Trauma or major surgery w/in 3 wk

• Recent internal bleed (w/in 2-4 wk); active PUD

• Noncompressible vascular punctures

• Prior SK exposure (if considering SK)

• Current use of anticoagulants

Primary PCI (ne)m 2007:356:47)

• Should be performed w/in 90 mins of arrival by skilled operator at high-volume center

• Superior to lysis: 27% i death. 65% i reMI. 54% i stroke. 95% i ICH (Loncet 2003:361.13)

• Transfer to center for 10 PCI may also be superior to lysis (DANAMi-2. NE}M 2003:349:733)

if can achieve acceptable door-to-balloon times (see below)

Fibrinolysis vs. Primary PCI

Assess Time and Risk

1.Time to presentation (efficacy of lytics i w/ Î time from sx onset)

2. Risk from STEMI (high-risk Pts fare better with mechanical reperfusion)

3. Risk of fibrinolysis (if high risk of ICH. PCI safer option)

4.Time required for transport to skilled PCI lab (benefit of PCI over lytic time-dependent)

If sx 3 h and no delay to invasive strategy, no pref. for either strategy

Fibrinolysis preferred

Primary PCI preferred

Early presentation ( 3 h) and delay to invasive strategy (see time goals in next column) Invasive strategy not an option (skilled lab unavailable or difficult vase, access)

Skilled PCI lab available w/o delay

Door-to-balloon < 90 min (Door-to-balloon)-(door-to-needle) < 1 h High-risk STEMI (shock Killip class -3) Contraindic. to lysis (incl ICH risk -4%) Late presentation (sx onset >3 h ago) Dx of STEMI in doubt

PO lab should have turpal backup. Adapted from ACCMHA 2004 STEMI Guideline« (On 2004;110:e82). Do not let decrtion regarding method of reperiuuon delay bme to reperfuskxi. Mort, t w/ time to rcperfuwon ("Ume ■ rtxrtcle-).

PO lab should have turpal backup. Adapted from ACCMHA 2004 STEMI Guideline« (On 2004;110:e82). Do not let decrtion regarding method of reperiuuon delay bme to reperfuskxi. Mort, t w/ time to rcperfuwon ("Ume ■ rtxrtcle-).

Nonprimary PCI

• Facilitated PCI: lytic before PCI harmful <Lancet 2006:367.569); upstream GPI under study

• Rescue PCI: beneficial if 50% ST segment resolution by 90 mins (nejm 2005:353:2758)

• Routine angio • PCI w/in 24 h of successful lysis: 1 D/MI/Revasc (lancet 2004:364:1045)

• Late PCI (median day 8) of occluded infarct-related artery: no benefit (N£fM 2006:355 2395)

Antithrombotic Therapy

Aspirin 162-325 mg PO (cnjjhed/ch«*«d)

23% I in death (tSIS-2. lancet 1988.«:349)

60 U/kg IVB (max 4000 U) 12 U/kg/h (max 1000 U/h)

No demonstrated mortality benefit T patency with fibrin-specific lytics Titrate to aPTT 50-70 sec

Enoxaparin

30 mg IVB x 1-1 mg/kg SC bid (.75 r- no bolw.0.75 mtfv* SC bid) (CrO 30 ml/mire 1 mg** SC qd)

(ExTRACT-TlMI 2S.NÉ/M 2006:354:1477)

PCI: acceptable alternative to UFH (age & CrCI

idjuiuncnu umeited in 1* PCI)

Fondaparinux

Clopidogrel

300 mg load 75 mg qd ( >75 r "0 tad vmh fcbrtnotyKc) ? 600 mg load if PCI

Lysis: superior to placebo & to UFH. with less bleeding (QASIS-6./AMA 2006-.29S.1S19)

PCI: risk of cath thromb.; should not be used Lysis: 41% T in patency. 7% i mort, no A in major bleed or ICH (ClARlTY-TiMi 28. nejm 2005:3511179. COMMÎT, txwc« 2005:366:1607) PCI: should be administered to all

GP llb/llla Inhibitors abciximab. eptifibatide. ? tirofiban

LySfS. no indication (GUSTOV.looc« 2001:357:1905) PC: 60% 1 D/MI/urg TVR (N^m 2001:344 189S)

Immediate Adjunctive Therapy

ß-blockers metoprolol 5 mg IV q5min x 3 then 25 mg PO q6h titrate to HR 55-60

20% i arrhythmic death or reMI. 30% * cardiogenic shock. & no A overall mortality when given to Pts incL those w 1 mod CHF (COMMIT. Lcncet 2005:3661622) Contromdicatcd if HR '60. SBP 100. moderate or severe CHF. 2°/3° AVB. severe bronchospasm

Nitrates

SL or IV

? -5% i mortality (lancet 1994:343:11 IS; 199S:34S 669) Use for relief of sx. control of BP. or Rx of CHF ControiixJic. in hypovolemia, sx RV infarcts, sildenafil

Oxygen

Use if necessary to keep S,Oi >90%.

Morphine

Relieves pain, i anxiety, venodilation — I preload

ACE inhibitors

Captopril 6.25 mg tid. titrate up as tolerated

-10% i mortality (tax« 1994;343:111S4 199S: 34S 669) Greatest benefit in ant. Ml. EF 40%. or prior Ml Contraindxoted in severe hypotension or renal failure

ARBs

Appear ACEI (VAUANT.N£/M 2003:349:20)

Insulin

Consider insulin infusion in 1st 48 h to normalize gle

• Diurese to achieve PCWP 15-20 1 pulmonary edema, i myocardial Oj demand

• i Afterload -*> 1 stroke volume & CO. i myocardial Oj demand can use IV NTG or nitroprusside (risk of coronary steal) — short-acting AC El

• Inotropes if CHF despite diuresis & 1 afterload; use dopamine, dobutamine. or milrinone

• Cardiogenic shock ( 7%) MAP - 60 mmHg.CI <2 L/min/mJ. PCWP 18 mmHg inotropes. IABP.VAD to keep CI >2; pressors (eg. norepinephrine) to keep MAP >60; coronary revascularization ASAP (N^M 1999:341*25)

IMI complications (Grc 1990:81:401;1995.123:509)

• Heart block ( 20%. occurs because RCA typically supplies AV node)

40% on present. 20% w/in 24 h. rest by 72 h; high-grade AVB can develop abruptly Rx: atropine, epi, isoproterenol, aminophylline (100 mg/min x 2.5 min). temp wire

• Precordial ST I (15-30%): anterior ischemia vs. true posterior STEMI vs. reciprocal As

• RV infarct (30-50%. but only 1/2 of those clinically significant)

hypotension; t JVP. • Kussmauls; 1 mm STE inV<R; RA/PCWP -0.8; prox RCA ocd. Rx: optimize preload (RA goal 10-14. ohj 1990:63.98);' contractility (dobutamine); maintain AV synchrony (pacing as neccssary); rcperfusion (nejm 1998:338933); mechanical support (IABP or RVAD); pulmonary vasodilators (eg. inhaled NO)

Mechanical complications (incid. <1% for each; typically occur a few days post-MI)

• Free wall rupture: large Ml in elderly, tear at jxn w/ nl myocardium; p/w PEA or hypoTN. pericardial sx. tamponade: Rj<: volume resusc.. ? pericardiocentesis, inotropes. surgery

• VSD: Ig Ml in elderly; AMI — apical VSD. IMI basal septum; 90% w/ harsh murmur ±

thrill (N£fM 2002347:1426); Rx: diuretics, vasodil.. inotropes. IABP. surgery, perc. closure

• Papillary muscle rupture: small Ml; more likely in IMI — PM pap. muscle (supplied by

PDA) than AMI -»AL pap. muscle (supplied by diags & OMs); 50% wI new murmur, rarely a thrill. T v wave in PCWP tracing; Rx: diuretics, vasodilators. IABP. surgery

Arrhythmias post-MI

• Treat as per ACLS for unstable or symptomatic bradycardias & tachycardias

• AF (10-16% incidence): (i-blocker, amiodarone. digoxin (particularly if CHF). heparin

• VT/VF: lido or amio x 6-24 h. then reassess;' |3B as tol„ replete K & Mg. r/o ischemia:

early monomorphic (- 48 h post-MI) does not carry bad prognosis

• Accelerated idioventricular rhythm (AIVR): slow VT ( 100 bpm), often seen after successful reperfusion; typically self-terminates and does not require treatment

• Consider backup transcutaneous pacing (TP) if: 2° AVB type I, BBB

• Backup TP or initiate transvenous pacing if: 2° AVB type II. BBB AVB

• Transvenous pacing (TV) if: 3° AVB: new BBB 2° AVB type II; alternating LBBB/RBBB

(can bridge w/ TP until TV, which it be« accompliihed under fluorotcopic guidance)

Other Post-MI Complications

Complication

Clinical features

Treatment

LV thrombus

30% incid. (esp. Ig antero-apical Ml)

Anticoagulate • 3-6 mo

Ventricular aneurysm

Noncontractile outpouching of LV; 8-15% incid.; persistent STL

Surgery if recurrent CHF. thromboemboli. arrhythmia

Ventricular pseudoaneurysm

Pericarditis

Rupture — sealed by thrombus and pericardium

10-20% incid.; 1-4 d post-MI @ pericardial rub; ECG As rare

Surgery

High-dose aspirin. NSAIDs Minimize anticoagulation

Dressler's syndrome

4% incid.; 2-10 wk post-MI Fever, pericarditis, pleuritis

High-dose aspirin. NSAIDs

Prognosis

• In registries, in-hospital mortality is 6% w/ reperfusion Rx (lytic or PCI) and 20% w/o

• Predictors of mortality: age. time to Rx. anterior Ml or LBBB. heart failure (Grc 2000:102:2031)

Killip Class

Class Definition

Mort.

1 no CHF

6%

II • S) and/or basilar rales

17%

III pulmonary edema

30-40%

IV cardiogenic shock

60-80%

(Am ] Cardiol 1967:20:457)

Forrester Class Mortality

PCWP (mmHg) 18 18

CI

2.2 <2.2

3% 9% 23% 51%

Predischarge Checklist and Long-Term Post-ACS Management

Risk stratification

• Stress test if anatomy undefined or significant residual CAD after PCI of culprit vessel

• Echocardiogram to assess EF Medications (barring contraindications)

• Antiplatelet Rx: ASA 81-162 mg indefinitely; Clopidogrel x 9-12 mos (? longer if DES)

• Statin: high-intensity lipid-lowering (eg. atorvastatin 80 mg. NEJM 2004:350 1495)

• ACEI: life-long if CHF. 1 EF. HTN. DM; 4-6 wks or at least until hosp. d/c in all STEMI

? long-term benefit in CAD w/o CHF (NEJM 2000.34214S & 2004:351 2058: Lancet 2003.362 782)

• Aldosterone antagonist: if EF <40% & signs of HF (see "Heart Failure")

• Nitrates: standing if symptomatic; SL NTG prn for all

• Warfarin: beyond indie for AF and LV thrombus, comb, of warfarin (goal INR 2-23) * ASA

J D/MI/CVA c/w ASA alone, but i bleeding (WARtS-u. nejm 2002:347:969)

• If sust. VT/VF >2 d post-MI not due to reversible ischemia

• No benefit solely for EF - 35% in 1st 40 d after Ml (DiNAMrr. nejm 2004:351:2481) Risk factors and lifestyle modifications

• Low chol. ( 200 mg/d) & low fat (<7% saturated) diet; LDL goal <70 mg/dl

• BP <140/90 mmHg, • 130/80 if diabetes or chronic kidney disease, consider 120/80

• Smoking cessation

• Influenza vaccination (Ore 2006:114:1549)

PA CATHETER AND TAILORED THERAPY

Theoretical considerations

• Cardiac output (CO) SV x HR; SV depends on LV end-diastolic volume (LVEDV)

manipulate LVEDV to optimize CO while minimizing pulmonary edema

• Balloon at tip of catheter inflated --» floats Into "wedge" position. Column of blood extends from tip of catheter, through pulmonary circulation, to a point just proximal to LA Under conditions of no flow. PCWP - LA pressure LVEDP. which is proportional to LVEDV

• Situations in which these basic assumptions fail:

1) Catheter tip not in West lung zone 3 (and . PCWP alveolar pressure - LA pressure)

2) PCWP > LA pressure (eg. mediastinal fibrosis, pulmonary veno-ocdusive disease)

4) Altered LVEDP-LVEDV relationship (ie. abnormal compliance, normal LVEDP may not be optimal in that Pi)

Indications (JACC 199&31840)

• Diagnosis and evaluation

Ddx of shock (cardiogenic vs. distributive) and of pulmonary edema (cardiogenic vs. not) Evaluation of CO. intracardiac shunt, pulmonary HTN, MR. cardiac tamponade

• Therapeutics

Tailored therapy to optimize PCWP. SV. SvOj in heart failure/shock Guide to vasodilator therapy (eg. inhaled NO. nifedipine) in pulmonary HTN Guide to perioperative management in high-risk patients

• Contraindications

Absolute: right-sided endocarditis, thrombus, or mechanical R-sided valve Relative: coagulopathy (reverse), recent PPM or ICD (place under fluoroscopy). LBBB (- 3% risk of CHB. place under fluoro). bioprosthetic R-sided valve Efficacy concerns

• No benefit to PAC in high-risk surgery or ARDS (/ama 2005:294:1664)

• No benefit in decompensated CHF yAMA 200S:294 1625); untested in cardiogenic shock

• Clinical estim. of CO & PCWP incorrect 1/2 the time (Choi 1991:99:1451). may use PAC to

(a) manage cardiogenic shock, or (b) answer hemodynamic question, then remove Placement

• Insertion site: right internal jugular vein or the left subclavian vein to facilitate

"anatomic" catheter tip flotation into the pulmonary artery

• Inflate the balloon when advancing and to measure PCWP

• Use resistance to inflation and pressure tracing to avoid overinflation

• Deflate the balloon when withdrawing and at all other times

• CXR should be obtained after bedside placement to assess for catheter position and PTX « If catheter cannot be successfully floated (typically if severe TR or RV dilatation) or if another relative contraindication exists, consider fluoroscopic guidance Complications

• Central venous access: pneumo/hcmothorax (1-3%), art. puncture, air embolism

• Catheter advancement atrial or ventricular arrhythmias. RBBB ( CHB in 3% of Pts w/ preexisting LBBB). catheter knotting, cardiac perforation and tamponade. PA rupture

• Catheter maintenance: infection (especially if catheter left in place for >3 d).

thrombus, pulmonary infarction (- 1.3%). PA rupture, balloon rupture Pressures in relation to respiratory cycle

• Intrathoracic pressure (usually slighdy 0) is transmitted to vessels and heart

• Transmural pressure ( preload) measured intracardiac pressure-intrathoracic pressure

• Always take measurements at end-expiration, when intrathoracic pressure closest to zero ("high point" In spont. breathing Pts: "low point" in Pts on (B pressure vent.)

• When intrathoracic pressures are I (lung disease. PEEP, auto-PEEP). measured PCWP

will overestimate true transmural pressures. Can approximate by subtracting V¡ PEEP.

Cardiac output

• Thermodilution: saline injected in RA A in temp, over time measured at thermistor

(in PA) used to calculate CO. May be inaccurate if low CO. severe TR. or intracardiac shunt.

• Fick method: O2 consumption (L/min) - CO (L/min) x arteriovenous Oj difference.

CO derived by dividing Oj consumption by observed AV O2 difference [10 ' 1.34 ml Oj/g Hb x Hb g/dl x (SjOj SvO})]. Oj consumption commonly estimated by weight-based algorithm. May be inaccurate in distributive shock (sepsis).

PA Catheter Waveforms

Location

RA

RV

PA

PCWP

Pressure (mmHg)

mean ü6

syst 15-30 diast 1-8

syst 15-30 mean 9-18 diast 6-12

mean s12

"" ___

J.

A

JL.

30-

25-

A

A.

Waves

20-

\

Hfl 15 10-5-0-

ÂÀ * y

J

\J X

* y

Comment

o atrul contraction.

occurs In PR interval < bulging of TV hack into

RA at son of systole v = Wood entering RA. occurs midT wave x - atrial relaxation and descent of base of heart y = exiung RA after TV

opens at start of diastole

RVEDP occurs right before upstroke and s mean RA pressure unless there is TS or TR

Waveform ihouM contain notch. Peak during T wave PA systolic RV systolic unless there is a gradient (eg, PS)

Similar to RA except doffipfwd and MiyM

o wave after QRS. z dutjnet c wave, v wave afitf T (help* dKtmgunh PCWP wi la/je v wavet 2' MR from W).

Hemodynamic Profiles

of Various Forms of Shock

RA

PCWP

CO

SVR

Type of shock

(|VP)

(CXR)

(UOP)

(Cap refill)

Hypovolemic

1

1

1

1

Cardiogenic

nl or 1

t

1

1

Septic - hyperdynamic

variable

variable

t

1

Septic - hypodynamic

variable

variable 4

nl or î

RV Infarct

t

nl or 1 I

t

Massive PE

t

nl or I 1

r

Tamponade

r

t 1

T

(Surrogate» for hemodynamic parameters shown bek>w parameter in parentheses.) Tailored therapy

• Goals: optimize both MAP and CO while I risk of pulmonary edema

MAP CO ■ SVR: CO HR < SV (which depends on preload, afterload. and contractility) pulmonary edema when PCWP -20-25 (higher levels may be tolerated in chronic CHF)

• Optimize preload LVEDV LVEDP LAP PCWP (nejm 1973:289:1263)

in Ml. LVEDP of 20-25 optimal - PCWP of 15-20 optimal (o wave boosts LVEDP) can optimize in individual Pt by measuring SV w/ different PCWP (create Starling curve) give NS or diurese (eg. furosemide) to achieve optimal filling pressures 4% albumin more potent volume expander than NS. but no improvement in mortality, except possibly in severe sepsis (safe, nejm 2004:350:2247)

• Optimize afterload [(peak pressure > radius) / (2 x wall thick.)] and .. * MAP & SVR

if SVR too high (- i SV & i CO): vasodilators (eg. nitroprusside. NTG. hydraL.ACEl) if SVR too low (— J MAP): vasopressors (eg. norepinephrine [a. |i], phenylephrine [a], or vasopressin [Vi] if septic shock or refractory to catecholamines, nejm 2001:345.588)

• Optimize contractility (no direct measure: SV a CO for a given preload & afterload)

if too low despite optimal preload & afterload: © inotropes (eg,dobutamit\e,m\lrw\o<\^

Early goal-directed therapy in septic shock (in first 6 h: nejm 2001:345: 1368)

• Arterial & central venous lines (no PAC) and measure central venous (not mixed) Oj sat

• Target CVP 8-12. MAP -65. & UOP -0.5 ml/kg/h using fluid & vasopressors as needed

• Target ScyOj ¿r70% using PRBCs and inotropes (dobutamine)

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