Most Myocardial Infarctions Are Caused by Low-Grade Stenoses
Pooled data from 4 studies: Ambrose et al, 1988; Little et al, 1988; Nobuyoshi et al, 1991; and Giroud et al, 1992. (Adapted from Falk et al.)
Falk E et al, Circulation , 1995.
Features of a Ruptured Atherosclerotic Plaque
Eccentric, lipid-rich
Fragile fibrous cap
Prior luminal obstruction < 50%
Visible rupture and thrombus
Constantinides P. Am J Cardiol. 1990;66:37G-40G.
Plaque rupture triggers
Emotional stress
Physical activity
Vasospasm
Cathecholamines
Vulnerable Versus Stable Atherosclerotic Plaques Libby P. Circulation. 1995;91:2844-2850. Vulnerable Plaque
Thin fibrous cap
Inflammatory cell infiltrates:
proteolytic activity
Lipid-rich plaque
Lumen Lipid Core Fibrous Cap
Thick fibrous cap
Smooth muscle cells: more extracellular matrix
Lipid-poor plaque
Stable Plaque Lumen Lipid Core Fibrous Cap
Coronary Remodeling (Adapted from Glagov et al.) Normal vessel Minimal CAD Progression Compensatory expansion maintains constant lumen Expansion overcome: lumen narrows Severe CAD Moderate CAD Glagov et al, N Engl J Med , 1987.
Atherosclerosis: A Progressive Process Disease progression PHASE I: Initiation PHASE II: Progression PHASE III: Complication Normal Fatty Streak Fibrous Plaque Occlusive Atherosclerotic Plaque Plaque Rupture/ Fissure & Thrombosis MI Stroke Critical Leg Ischemia Coronary Death Unstable Angina Libby P. Circulation. 2001;104:365-372.
IVUS=intravascular ultrasound Nissen S, Yock P. Circulation 2001 ; 103: 604–616 Angiogram IVUS Little evidence of disease Atheroma No evidence of disease The IVUS technique can detect angiographically ‘silent’ atheroma
Correlation of CT angiography of the coronary arteries with intravascular ultrasound illustrates the ability of MDCT to demonstrate calcified and non-calcified coronary plaques (Becker et al., Eur J Radiol 2000) Non-calcified, soft, lipid-rich plaque in left anterior descending artery (arrow) . The plaque was confirmed by intravascular ultrasound (Kopp et al., Radiology 2004)
Estimated 10-Year CHD Risk in 55-Year-Old Adults According to Levels of Various Risk Factors : Framingham Heart Study A B C D Blood Pressure (mm Hg) 120/80 140/90 140/90 140/90 Total Cholesterol (mg/dL) 200 240 240 240 HDL Cholesterol (mg/dL) 50 50 40 40 Diabetes No No Yes Yes Cigarettes No No No Yes Source: Circulation 1998;97:1837-1847.
The INTERHEART Study Metabolic risk factors and their influence on the occurrence of AMI
Feb. 1999 to Mar 2003, 15,000 cases of AMI were compared with 15,000 controls in 52 countries
The prevalence of modifiable RF, calculation of the population attributable risk (PAR)
Frequency of RF in total pop. – Frequency of RF in those without MI
Frequency of RF in total pop.
Yusuf S et al. Lancet 2004, 364;937-962
The INTERHEART Study Population Attributable Risk (cumulated men& women)
Smoking DM Abdo Obesity Abn Lipids
PAR in%
Western Europe 29.3 15.0 63.4 44.6
Central Eastern Eu 30.2 9.1 28.0 35.0
Middle East 45.5 15.5 25.9 70.5
Africa 38.9 16.7 58.4 74.1
South Asia 37.4 11.8 37.7 58.7
South East Asia+ Japan 36.7 21.0 58.0 67.7
Australia+NZ 44.8 7.2 61.3 43.4
South America 38.3 17.7 45.5 47.6
North America 26.1 13.0 59.5 50.5
All 52 countries 36.4 12.3 33.7 64.1
Yusuf S et al. Lancet 2004, 364;937-962
INTERHEART: Risk of AMI Associated With Risk Factors
Risk Factor Control(%) Case AMI(%) OR ( adj.for age,sex, smoking)
Lipid(ApoB/ApoA-1) 20.0 33.5 3.87
Current smoking 26.8 45.2 2.95
DM 7.5 18.4 3.08
HT 21.9 39.0 2.48
Abdo. Obesity 33.3 46.3 2.22
Psychosocial 2.51
Veg.& Fruit daily 42.4 35.8 0.70
Exercise 19.3 14.3 0.72
Alcohol intake 24.5 24.0 0.79
Yusuf S et al. Lancet 2004, 364;937-962
Discharge Dx
Gender
Risk factors
Prevalence of RF according to gender
Relationship Between Changes in LDL-C and HDL-C Levels and CHD Risk Third Report of the NCEP Expert Panel. NIH Publication No. 01-3670 2001. http://hin.nhlbi.nih.gov/ncep_slds/menu.htm 1% decrease in LDL-C reduces CHD risk by 1% 1% increase in HDL-C reduces CHD risk by 3%
CHD Outcomes in Clinical Trials of LDL Cholesterol-Lowering Therapy Mean CHD CHD No. No. Person- cholesterol Incidence Mortality Intervention trials treated years reduction (%) (% change) (% change) Surgery 1 421 4,084 22 -43 -30 Sequestrants 3 1,992 14,491 9 -21 -32 Diet 6 1,200 6,356 11 -24 -21 Statins 12 17,405 89,123 20 -30 -29 Source: This table is adapted from the meta-analysis of Gordon, 2000.
Relation Between LDL-Cholesterol Reduction And Risk Of Cardiovascular Events % LDL-C Reduction 10 0 20 40 70 % Reduction In Risk Of Nonfatal MI Or CHD Pravastatin LRC-CPPT WOSCOPS CARE POSCH 4S (Simvastatin) 13 26 35 60 % LDL-C Reduction 10 0 20 40 70 % Reduction In Risk Of Nonfatal MI Or CHD (4.5 y) LRC-CPPT ( P >.05) WOSCOPS CARE POSCH ( P >.05) 4S (Simvastatin) 13 26 35 60 *
When outcomes at 4.5 y are considered, beneficial effects of statins occurred more rapidly
These effects may not be entirely cholesterol dependent; *difference possibly due to pleiotropic effects
Reproduced from Liao and Laufs. Annu Rev Pharmacol Toxicol . 2005;45:89, with permission from Annual Reviews . www.annualreviews.org. Liao. Am J Cardiol . 2005;96(suppl):24F.
Vessel Wall And Endothelial Cell Membrane Changes With Atherogenesis Reproduced from Mason et al. Circulation . 2004;109(suppl II):II-34, with permission. Mason et al. Am J Cardiol . 2005;96(suppl):11F.
Role Of Statins In ACS: Non-Lipid Effects ( Pleiotropic effects) ADP = adenosine diphosphate; CD40-L = CD40 ligand; IFN = interferon; IL = interleukin; vWF = von Willebrand factor. Reproduced from Ray and Cannon. J Thromb Thrombolysis . 2004;18:89, with permission. Cannon and Ray. Am J Cardiol . 2005;96:54F.
Clinical Events Correlate Directly With On-Treatment LDL-Cholesterol Levels P = placebo; S = statin. Reproduced from O'Keefe et al. J Am Coll Cardiol . 2004;43:2142, with permission. CHD Events (%) 10 9 8 7 6 5 4 3 2 1 0 -1 55 75 95 115 135 155 175 195 LDL Cholesterol (mg/dL) y = 0.0599x - 3.3952 R 2 = 0.9305 P =.0019 AFCAPS-S WOSCOPS-S ASCOT-S ASCOT-P AFCAPS-P WOSCOPS-P Primary prevention: 4-5 yr duration
ASCOT-LLA: Nonfatal MI And Fatal CAD Primary End Point Adapted from Sever et al. Lancet . 2003;361:1149, with permission. Sever et al. Am J Cardiol . 2005;96(suppl):39F. 2 0 1 4 3 Years 0.0 0.5 1.0 1.5 2.0 2.5 3.0 3.5 Cumulative Incidence (%) Placebo Atorvastatin 10 mg Number of Events 36% Reduction HR = 0.64 (0.50-0.83) P =.0005 Number of Events 154 100 N=10,305
Effects of Lipid-Lowering Therapy on CHD Events in Statin Trials 25 20 15 10 5 0 Patients with CHD event (%) 90 110 130 150 170 190 210 S = statin-treated P = placebo-treated *Extrapolated to 5 y 4S - P CARE - P LIPID - P 4S - S WOSCOPS - S WOSCOPS - P AFCAPS - P AFCAPS - S LIPID - S CARE - S Primary prevention Simvastatin Pravastatin Lovastatin Modified from Kastelein JJP. Atherosclerosis. 1999;143(suppl 1): S17-S21. HPS - S HPS - P Atorvastatin ASCOT - S * ASCOT - P * Secondary prevention LDL-C (mg/dL)
PROVE IT-TIMI 22: A Major Cardiovascular Event Or Death From Any Cause Primary End Point Adapted from Cannon et al. N Engl J Med . 2004;350:1495, with permission. Ray and Cannon. Am J Cardiol . 2005;96(suppl):54F. 15 0 10 30 25 5 20 Months Of Follow-Up 0 3 9 15 21 6 12 18 24 27 30 Death Or Major Cardiovascular Event (%) Pravastatin 40 mg Atorvastatin 80 mg P =.005 Overall P =.03 n= 4,162 with CHD
PROVE IT-TIMI 22: Effect Of Different Statin Regimens On LDL Cholesterol And CRP
Biological Statin Response Regimen Baseline 30 Days 4 Months
LDL mg/dL (mean) Pravastatin 40 mg 106 88 97 Atorvastatin 80 mg 106 60 67 P value NS <.001 <.001 CRP mg/L (median) Pravastatin 40 mg 11.9 2.3 2.1 Atorvastatin 80 mg 12.2 1.6 1.3 P value NS <.001 <.001 Cannon et al. N Engl J Med . 2004;350:1495. Ridker et al. N Engl J Med . 2005;352:20. Reproduced from Ray and Cannon. Am J Cardiol . 2005;96(suppl):54F, with permission.
PROVE IT-TIMI 22: A Major Cardiovascular Event Or Death From Any Cause At Different Censoring Times Reproduced from Cannon et al. N Engl J Med . 2004;350:1495, with permission. Ray and Cannon. Am J Cardiol . 2005;96(suppl):54F. Censoring Time Hazard Ratio (95% CI) Risk Reduction (%) Event Rate (%) Atorvastatin Pravastatin 30 days 90 days 180 days End of follow-up 17 1.9 2.2 18 6.3 7.7 14 12.2 14.1 16 22.4 26.3 0.50 0.75 1.0 High-Dose Atorvastatin Better Standard-Dose Pravastatin Better 1.50 1.25
NCEP-ATP III National Cholesterol Education Program Adult Treatment Panel III
Evolution of Lipid Management Guidelines ATP I (1988) ATP II (1993) ATP III (2001) Diet; low-dose, nonstatin monotherapy High-dose statin, combination therapy Low- to moderate-dose statin monotherapy Increasing aggressiveness of cholesterol-lowering therapy The National Cholesterol Education Program (NCEP) Adult Treatment Panel (ATP)
Update to ATP III: Risk Categories, LDL-C Goals Implications of Recent Clinical Trials for the National Cholesterol Education Program Adult Treatment Panel III Guidelines: Circulation . 2004;110:227-239. <160 <130 <130 <100 (optional <70) LDL-C Goal (mg/dL) > 160 > 130 > 130 > 100 Initial TLC (mg/dl) > 130 (optional 100-129) Moderately high risk: 2+ risk factors (10-year risk 10-20%) > 190 (optional 160-189) Lower risk: 0–1 risk factor >160 Moderate risk: 2+ risk factors (10-year risk 10%) > 100 (optional <100) High risk: CHD or CHD risk equivalents (10-year risk >20%) Consider drug (mg/dl) Risk Category
Am J Cardiol. 2004;93: 154-8
HDL LDL TG Total chol
Cardiac Emergency
Cardiac Emergency
Acute coronary syndrome
Arrhythmia
Hypertensive emergency
Aortic dissection
Cardiac tamponade
P : P recipitating , Position
Q : Quality and Quantity
R : Region, Radiate, Refer
S : Symptom associated
T : Timing , Terminating
Taking Hx of obscure pain
Acute myocardial infarction
Acute aortic dissection
Acute pulmonary embolism
Tension pneumothorax
Killer chest pain
Characteristics of Typical and Atypical angina pectoris (1)
Typical
Substernal
Burning, heavy, or squeezing feeling
Precipitated by exertion or emotion
Promptly relieved by rest of NTG
Angina chest pain
DDx of AMI
Aortic dissection
Acute pericarditis
Acute pulmonary embolism
Intercostal neuralgia
Costochondritis
Abdominal visceral disorders
PU, Pancreatitis, biliary colic
Atypical symptoms
Elderly
Women
Diabetes
Post operation
Angina equivalent
AMI Definition • Chest pain • ECG • Troponin positive
STEMI Blood flow Chest discomfort PMVT, VF Sudden Death M. Ischemia Heart failure Cardiogenic shock Elevated +CK,Trop-T M.stunning Consequences after acute coronary artery occlusion NSTEMI ,UA Cardiovascular Research & Prevention Center, Bhumibol Adulyadej hospital
Total ischemic time A B C ER Rx <30min (lytic) <90 min (PCI) CP reperfuse microvascular epicardial
การคัดกรอง
Fast Track MI
EKG ด่วนแพทย์ดูใน 10 นาที
ST elevation ตาม staff cardio ทันที
No ST elevation ………………. MD.
30-day mortality (%) Relationship between 30-day mortality and Door to Balloon time( N=522 ) Berger et al. Circulation 1999;100:14-20 P=0.001
PCI vs Fibrinolysis with fibrin-specific agents
Fribrinolysis is generally preferred if
Early presentation < 3 hr from symptom onset and delay to invasive strategy
Invasive strategy is not an option
Cath-lab occupied/not available
Vascular access difficulties
Lack of access to a skilled PCI lab
Delay to invasive strategy
Prolonged transport
(D-to-B) - (D-to-N) > 1 hr
Contact-to-B or D-to-B > 90 min
Invasive Strategy is generally preferred if
Skilled PCI lab available with surgical backup
(D-to-B) - (D-to-N) < 1 hr
Contact-to-B or D-to-B < 90 min
Contraindications to fribrinolysis including increased risk of bleeding of ICH
Late presentation
The symptom onset was >3 hr ago
Assessment of Reperfusion Option for Patients with STEMI
Step 1: Assess Time and Risk
Time since onset of symptoms
Risk of STEMI
Risk of fibrinolysis
Time required for transport to a skilled PCI lab
Step 2 : Determine of Fibrinolysis or an Invasive Strategy is preferred
If presentation in < 3 hr and there is no delay to an invasive strategy, there is no preference for either strategy
Absolute Contraindication for thrombolytic Rx
A: Aortic dissection
B: Bleeding ( active in 2-4 wk or bleeding diathesis)
C: Cranial :
Any prior ICH,
3 mo of ischemic stroke or closed head trauma,
Intracranial neoplasm
D: Drug allergy
60 yo man, smoker, 1hr severe CP, BP 100/60
58 yo lady, DM HT, syncope, sweating, CP 2/10, BP 80/60
V4R
68 yo man, 3 hrs 8/10 CP, BP 100/60
Algorithm for ECG identification of the IRA in Anterior MI STE in V 1 , V 2 and V 3 STE in V1 (>2.5 mm) and AVL or RBBB with Q wave or both ST depression (<1 mm) in II, III, and AVF STE in II, III, and AVF Wrap around
A 63 yo lady, 3 hrs 7/10 CP Given Metalalyse + Clexane , continuing chest pain, VF x II in cath lab
AMI in LBBB
Q wave : not be used
Indicator : Primary ST change
ST deviation in the same( concordant) direction as the major QRS vector
Concordant ST changes
elevation > 1 mm concordant with QRS
ST depression > 1 mm in leads V1, V2, or V3
Extremely discordant
ST elevation > 5 mm discordant with QRS
ST elevation without infarction
LVH
LBBB
Benign early repolarization
Brugada’s syndrome
LV aneurysm
Acute pericarditis
Myocarditis
Ventricular pace rhythm
ED :55 yo man, 3 hrs Lt. CP 5/10, less with sits forward
GP: 34 yo athlete, anterior CP 3/10, pt. of tenderness Fish hook
60-yo man severe headache and collapsed
Conditions Associated with TDP
E’lyte abnormality
K + , Mg ++ , Ca ++
Drug-related
Antiarrhythmic
IA, IC, III
Psychotropic agents
Organophosphate
Liquid protein diet
Cardiac disease
IHD, myocarditis
Bradycardia
CNS disease
Intracranial lesion
SAH
Congenital LQTS
Tachycardia with pulse
Stable or unstable
Unstable ( rate usually >150/min)
Altered mental status
Chest pain
Hypotension
Signs of shock
If Unstable Cardioversion
Cardioversion
AF : 100,200,300,360 J
Stable MMVT:100,200,300,360 J
SVT or A flutter:50,100,200,300,360 J
PMVT: Rx as VF
Synchronized mode?
Stable tachycardia Narrow QRS
SVT
Vagal ma.
Adenosine
6/12/12 mg IV
Regular Irregular Regular Irregular Wide QRS
AF, Aflutter, MAT: Diltriazem, B-blocker
MMVT
Amiodarone 150 mg iv in 10 min repeat as needed
Cardioversion
AF with WPW : Amiodarone 150 mg iv
TDP: MgSO 4 1-2 g iv
Treat possible contributing factors: 6H-5T
SVT after Rx with Adenosine 6mg IV
AF with WPW: How to Rx? Unstable : Cardioversion 100 J Stable : Amiodarone 150 mg IV
34-yo lady, gen. edema 3 mo.
Cardiac tamponade
Pericardiocentesis
Hemopericardium
23-y-old man with fever 7 day and chest pain
Pericardial fluid
Hypertensive crisis
Definition
Severe elevation in BP ( >220/120 mmHg)
Sub classified into emergency and urgency
Hypertensive emergency
Require an immediate reduction in BP ( 1 hr )
Rx IV therapy and in ICU
Hypertensive urgency
No evidence of progressive end-organ injury
Require only gradual reduction in BP in 24-48 hr
Wong, T. Y. et al. N Engl J Med 2004;351:2310-2317 Examples of Mild Hypertensive Retinopathy AV nicking Focal narrowing AV nicking Copper wiring
Accelerated-malignant HT
Fundoscopic changes
Retinal hemorrhages
Exudates
Papilledema
HT and autoregulation of CBF
CBF : cerebral perfusion pressure ( CPP)
CPP= MAP - ICP
MAP = DBP + 1/3 Pulse pressure
Cerebral Autoregulation Mean arterial pressure (mmHg) Cerebral blood flow (ml/100 gm per min ) 50 100 150 200 150 100 50 0 Normotensive Hypertensive Strandgaard S,et al; Br Med J 1:507, 1973
Goal of Rx in HT emergency
Reduce mean arterial BP no > 25%
Within minutes to 1 hours
Toward 160/110 mmHg within 2- 6 hours Toward normal BP in 24- 48 hours JNC VII. JAMA 2003;289:2560-2572
Pitfalls in the Rx
Excessive falls in BP should be avoided
ischemia : Renal, cerebral, cardiac
SL/ short acting Nifedipine: not recommended
Three exceptions
Ischemic stroke
Aortic dissection SBP should < 100 mmHg (+/-)
Lower BP for thrombolytic Rx ( Stroke )
Acute ischemic stroke and BP
SBP>220 mmHg or DBP 120-140 mmHg
Caution reduction of BP 10%-15%
Carefully monitoring Neuro signs /BP
DBP> 140 mmHg
IV infusion of Na nitroprusside
Reduce BP 10%-15%
Lytic Rx within first 3 hrs
>185/110 mmHg : contraindication
BP > 180/105 mmHg : iv anti HT
American Stroke Association. Stroke 2003;34
Acute aortic dissection
Suspected diagnosis
BP to the lowest tolerate level in 15-30 min
Initial Rx : IV NaNTP and IV Beta-blocker
Contraindication : hydralazine, nifedipine
Stimulation of sympathetic activity
Increase shear stress on the aortic wall
Approach to HT crisis BP > 220/120 mmHg Headache No neurosign No target organ damage Urgency Identify the cause and Rx the cause ( panic, anxiety) Otherwise use oral anti HTagent Neurosign( encep., stroke) Retinopathy gr III, IV severe chest pain ( IHD, dissecting aneu) Pulmonary edema Cathecholamine excess ARF Emergency IV therapy Recheck in 6-24 hr
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