JournalJournal ReadingReadingMyocardial infarction in young peopleMyocardial infarction in young peopleCardiol J 2009; 16, 4: 307–311Cardiol J 2008; 15: 21–25

Presented by R Presented by R 王郁菁王郁菁2011-06-16 at ER conference room2011-06-16 at ER conference room

Introduction Introduction

The borderline differentiating The borderline differentiating younger from older patients is the younger from older patients is the age of 40age of 40..

MI in patients below the age of 40 MI in patients below the age of 40 constitute about constitute about 10%10% of all cases. of all cases.

The majority of sufferers are The majority of sufferers are menmen Increasing prevalence among womenIncreasing prevalence among women 1 in 4 patients with MI <45 years are 1 in 4 patients with MI <45 years are

womenwomen

Cardiol J 2009; 16,4: 307-311

Causes Causes

Main cause: Main cause: coronary coronary atherosclerosisatherosclerosis About About 80%80% of cases of cases Usually Usually one vessel diseaseone vessel disease Significant lesions in coronary arteries Significant lesions in coronary arteries

may be present as early as age 25-30may be present as early as age 25-30 >40, the first symptoms of exercise->40, the first symptoms of exercise-

induced ischemia are not uncommoninduced ischemia are not uncommon Environmental influence on genotype Environmental influence on genotype

may promote the development of may promote the development of coronary artery disease in young agecoronary artery disease in young age

Cardiol J 2009; 16,4: 307-311

Cardiol J 2009; 16,4: 307-311

AtherosclerosisAtherosclerosis

SmokingSmoking Religa et alReliga et al

100 women with first MI: 45% were smoker100 women with first MI: 45% were smoker <45 y/o: 95% were smoker<45 y/o: 95% were smoker Impairs endothelium derived vasodilation mechanisms Impairs endothelium derived vasodilation mechanisms

and vasospasm in coronary arteriesand vasospasm in coronary arteries

Dyslipidemia: Dyslipidemia: 29%29% Premature coronary artery disease is most Premature coronary artery disease is most

common in patients with common in patients with familial familial hypercholesterolemiahypercholesterolemia, less often in familial , less often in familial mixed dyslipidemiamixed dyslipidemia

High TG, high total cholesterol (LDL), low HDLHigh TG, high total cholesterol (LDL), low HDLCardiol J 2009; 16,4: 307-311

AtherosclerosisAtherosclerosis

Premature ischemic heart disease in Premature ischemic heart disease in first-degree relativesfirst-degree relatives

an independent risk factoran independent risk factor Apolipoprotein E (Allel E4): an important Apolipoprotein E (Allel E4): an important

risk factor for atherosclerosis and IHDrisk factor for atherosclerosis and IHD Arterial hypertension: 5%Arterial hypertension: 5% ObesityObesity

Doubles the risk of MI in menDoubles the risk of MI in men Increases the risk in women by 2.5 timesIncreases the risk in women by 2.5 times Excessive accumulation of TG impairs Excessive accumulation of TG impairs

the function of cardiomyocytes, liver and the function of cardiomyocytes, liver and pancreaspancreas

Cardiol J 2009; 16,4: 307-311

Causes without coronary Causes without coronary artery stenosis artery stenosis

Coronary artery embolismCoronary artery embolism ThrombosisThrombosis AnomalyAnomaly Vessel inflammation or spasmVessel inflammation or spasm

Cardiol J 2009; 16,4: 307-311

Coagulation disordersCoagulation disorders

5% of all cases5% of all cases Imbalance between coagulation Imbalance between coagulation

and fibrinolysisand fibrinolysis increase risk of increase risk of thrombus formingthrombus forming

Cardiol J 2009; 16,4: 307-311

Anomaly Anomaly

Rare casesRare cases Myocardial bridgeMyocardial bridge

Coronary arteries tunnels through Coronary arteries tunnels through the myocardiumthe myocardium

15-85% is found during autopsies15-85% is found during autopsies 0.5-2.5% is found from angiography0.5-2.5% is found from angiography

Cardiol J 2009; 16,4: 307-311

Drug abuse Drug abuse

CocaineCocaine AmphetamineAmphetamine Increasing numbers of MIIncreasing numbers of MI MI after cocaine abuse was first MI after cocaine abuse was first

reported in 1982. reported in 1982.

Cardiol J 2009; 16,4: 307-311

Cocaine or Amphetamine Cocaine or Amphetamine abuseabuse

Causes Causes heart rate and systolic blood heart rate and systolic blood pressure increase with artery spasmpressure increase with artery spasm Reduced coronary flowReduced coronary flow imbalance imbalance

between oxygen consumption and supplybetween oxygen consumption and supply Increase in thrombocytes aggregationIncrease in thrombocytes aggregation Blocking of sodium channels and the Blocking of sodium channels and the

presynaptic part of neuronpresynaptic part of neuron Excessive release of neurotransmitters Excessive release of neurotransmitters

like norepinephrine and dopaminelike norepinephrine and dopamine Transient impairment of blood flowTransient impairment of blood flow

Cardiol J 2009; 16,4: 307-311

Direct toxin lesion of myocardiumDirect toxin lesion of myocardium, , resulting in focal necrosisresulting in focal necrosis Marijuana smokerMarijuana smoker

Overdosing on medicines: Overdosing on medicines: RifampicineRifampicine

Toxic influence on endothelium Toxic influence on endothelium may be the cause of drug-induced may be the cause of drug-induced acute coronary syndromesacute coronary syndromes

Cardiol J 2009; 16,4: 307-311

Uric acidUric acid

Another study: 2000.01-2005.12Another study: 2000.01-2005.12 80 patients were less than 35 80 patients were less than 35

years old and were diagnosed as years old and were diagnosed as AMIAMI

Cardiol J 2008; 15: 21-25

Hyperuricemia: >7.0mg/dlHyperuricemia: >7.0mg/dl An independent factor of mortalityAn independent factor of mortality Underlying mechanisms remain unclearUnderlying mechanisms remain unclear HypothesisHypothesis

Promotes vascular smooth muscle Promotes vascular smooth muscle proliferation and upregulates the proliferation and upregulates the expression of platelet-derived growth factor expression of platelet-derived growth factor and monocyte chemoattractant protein-1and monocyte chemoattractant protein-1

May induce endothelial dysfunction by May induce endothelial dysfunction by decreasing the production of nitric oxide in decreasing the production of nitric oxide in the vascular endothelial cellsthe vascular endothelial cells

Cardiol J 2008; 15: 21-25

Prognosis Prognosis

If patients have DM, that may have If patients have DM, that may have multi-vessel lesionmulti-vessel lesion

Young patients usually have no Young patients usually have no concomitant disordersconcomitant disorders

After MI in young patientsAfter MI in young patients Higher LVEFHigher LVEF Lower levels of pro-BNP than older groupsLower levels of pro-BNP than older groups Favorable clinical courseFavorable clinical course Increased risk of recurrent coronary Increased risk of recurrent coronary

events concerns only 5%events concerns only 5% Problem of sudden death risk remains Problem of sudden death risk remains

Cardiol J 2009; 16,4: 307-311

Thanks for your Thanks for your attention!!attention!!