Transcript Slide 1
ACUTE CORONARY SYNDROME (ACS) ACS Pathophysiology is that of a ruptured or eroded atheromatous plaque. Acute Myocardial Infarction (AMI) – ST-segment elevation MI (STEMI) – Non-ST-segment elevation MI (NSTEMI) Unstable Angina (UA) Goals of Therapy in ACS Reduce the amount of myocardial necrosis that occurs in patients with MI, preserving left ventricular function and preventing heart failure Prevent major adverse cardiac events: death, nonfatal MI, and need for urgent revascularization Treat acute, life threatening complications of ACS, such as ventricular fibrillation/pulseless ventricular tachycardia, symptomatic bradycardias, and unstable tachycardias Acute Coronary Syndromes Algorithm Circulation 2005;112:IV-89-IV-110 Copyright ©2005 American Heart Association Targeted History Chest discomfort – what, where, when & how much? Associated Signs & symptoms – dyspnea, diaphoresis, nausea Prior cardiac history – similar pain? Risk Factors Pertinent PmHx EKG ST-segment elevation or presumed new LBBB is characterized by ST-segement elevation >1mm in 2 or more contiguous precordial leads or 2 or more adjacent limb leads and is classsified as ST-elevation MI Ischemic ST-segment depression> or = 0.5mm or dynamic T-wave inversion with pain or discomfort is classified as high-risk UA or NSTEMI. Transient ST elevation of < 20 minutes is also included within this catagory Normal or nondiagnostic changes in ST segment or T-waves are inconclusive and require further risk stratification. This includes patients with normal EKGs and those with ST-segment deviation of <0.5 Cardiac Biomarkers CK & CK-MB – Rise 4-6 hours after injury – Peak 12-24 hours after injury – Return to baseline in 24-48 hours Troponin – Most sensitive and specific – Rises 4-6 hours after injury – Peaks 18-24 hours after injury – May take a week to return to baseline Longer if poor renal function Reperfusion Ultimate goal in ACS and immediate goal in STEMI Shown to reduce mortality by 47% Major determinants of myocardial salvage and long term prognosis are – Short time to perfusion – Complete and sustained patency of the infarcted artery with normal flow – Normal microvascular perfusion Percutaneous Coronary Intervention (PCI) Treatment of choice if can be performed in <90 minutes from patient presentation Goal should be <30 minutes from patient presentation to either PCI, or transfer to facility that performs PCI Also preferred in patients with contraindications to fibrinolysis and is reasonable in patients with cardiogenic shock or heart failure. Fibrinolysis Indicated for STEMI if <12 hours of symptoms and PCI unable to be performed in <90 minutes Goal is “door to needle” time of <30 minutes Absolute contraindications include: prior intercranial hemorrhage, AVM or malignant neoplasm, ischemic stroke>3 hour and<3months, suspected aortic dissection, active bleeding or bleeding diathesis, significant closed head or facial trauma < 3months Acute Coronary Syndromes Algorithm Circulation 2005;112:IV-89-IV-110 Copyright ©2005 American Heart Association