Acute coronary syndrome

It includes unstable angina and Myocardial infarction

New onset angina or rapidly worsening angina ,or angina on minimal exertion /rest in absence of myocardial damage

Myocardial infarction occurs when angina symptoms occurs at rest and evidence of myocardial necrosis by elevated troponin and creatine kinase MB

Clinical features

1.Symptoms- 

            Prolonged cardiac pain: chest, throat, arms, epigastrium or back

            Anxiety and fear of impending death

            Nausea and vomiting  

            Breathlessness

      Collapse/syncope

2.Signs-

• Signs of sympathetic activation: pallor, sweating, tachycardia 
• Signs of vagal activation: vomiting, bradycardia
• Signs of impaired myocardial function-Hypotension, oliguria, cold peripheries ,Narrow pulse pressure ,Raised JVP ,Third heart sound ,Quiet first heart sound ,Diffuse apical impulse ,Lung crepitations
• Signs of tissue damage:Fever

Sudden death in Acute MI  due to arrhythmia or  arrest(If VF->Give DC shock  or If asystole->Give Pacemaker

Criteria of myocardial infarction

Any one of-

• Biomarker above 99th centile with any of-S/S ,new ST-T change ,new LBBB ,pathologic Q wave ,imaging evidence of  myocardial loss ,thrombus detected by angiography
• Cardiac death with sign symptoms
• PCI-related MI
• CABG related MI
• Stent related MI

Criteria of prior MI

Any one of-

• Pathological Q wave with/without S/S
• Imaging evidence of myocardial loss

Investigation

1.ECG-

         STEMI-Transmural MI ,ST elevated ,inverted T wave

         NSTEMI-Subendocardial MI ,ST depressed ,absence of Q  wave

2.Ecocardiogram

3.Cardiac specific troponin I&T(Most specific)-Raised within 4-6 hours ,remains 2 weeks

4.CKMB-Raised within 4-6 hours ,remains 72 hours

Management

Immediate hospitalization

• 1st 12 hours-300mg aspirin with 600mg clopidogrel ,then 150mg clopidogrel daily for 1 week ,then 75mg daily
• LMW heparin
• Morphine I/V
• GTN
• Beta blockers
• Ca antagonist

Arrhythmias in acute coronary syndrome

• VF ,VT ,VE ,AF ,AT ,AV block

Complication

• Arrhythmia ,ischaemia ,acute circulatory failure ,pericarditis ,embolism(Stroke)
• Mechanical-Ruptured papillary muscle ,rupture IV septum ,rupture ventricle

[Question.AMI with ST elevated ,6 months later still elevated?-Ventricular aneurysm(Remodeling)

X ray-Cardiac silhoutte is unusually bulged

Post MI prevention-Aspirin with clopidogrel for 3 months]