Immediate and Long-Term Therapy of Patients with Acute Coronary Syndromes with Thienopyridines. Current Status According to the Latest European Society of Cardiology (ESC) Guidelines

摘要

For patients with acute coronary syndrome (ACS), the first priority is to alert emergency services. In addition to an ECG (ideally taken during the first medical contact at the patient’s home), the key of life saving is the immediate antithrombotic therapy with acetylsalicylic acid (ASA) and (unless contraindicated) an injection of unfractionated heparin or bivalirudin as an alternative anticoagulant. Dual anti-platelet therapy (ASA combined with other antiplatelet drugs, like thienopyridines) should be started as soon as possible in the ambulance or at the latest in the hospital. For clopidogrel, a loading dose of 600 mg is the standard. To avoid the risk of an unknown low or missing clopidogrel response, prasugrel is recommended instead, with administration of a loading dose of 60 mg, if no contraindication (s/p stroke or TIA) exists. When PCI is planned, the ambulance must head directly to the nearest hospital with continuous (24/7) PCI service within 90 (to 120) minutes. The maintenance dose for clopidogrel is 75 mg/d; a daily double-dose has not proven to be superior, even in “low responders”. For prasugrel, the maintenance dose is usually 10 mg/d. To avoid bleeding complications in patients ≥ 75 y and/or < 60 kg, a prasugrel maintenance dose of 5 mg/d is recommended. The ESC guidelines recommend DAPT for 1 year after ACS in all patients – independent of the type of ACS and independent of whether any or which coronary stent has been implanted. With DAPT, the patient – and not the stent – is treated.Keywords: Acute coronary syndrome, myocardial infarction, clopidogrel, prasugrel, percutaneous coronary intervention, stentBACKGROUNDDespite the extensive scientific knowledge of cardiovascular risk factors and despite educating the general public, cardiovascular diseases continue to be the leading cause of death. Patients with acute coronary syndromes (ACS) are at particular risk. The immediate measures initiated in these patients often determine if the outcome is life or death. The objective of this overview is the evaluation of the current guidelines to effect practical therapy tips for primary and secondary health care providers, with special focus on the antiplatelet treatment with thienopyridines.DEFINITION OF ACUTE CORONARY SYNDROMEDepending on the symptoms and objective findings, ACS comprises three distinct syndromes (Table 1): acute myocardial infarction with persistent ST-segment elevation (STEMI), acute myocardial infarction without ST-segment elevation (NSTEMI), and unstable angina pectoris (UAP). NSTEMI and UAP are often combined to NSTE-ACS. A (presumably) new-onset left bundle branch block (LBBB) is – depending on the symptoms – initially to be regarded as a STEMI. For STEMI, the symptoms and the electrocardiogram (ECG) are sufficient for diagnosis; one does not have to wait for the results of troponin or CK-MB. In an ideal setting with short system delay times, troponin, if determined, would be negative anyway within the first 6 hours after onset of symptoms. For NSTE-ACS, a positive troponin is the first determining factor for NSTEMI (Table 1, Figure 1).Table 1Definition of the three forms of acute coronary syndromes (ACS).Figure 1Suggestion for immediate pre-hospital measures in patients with acute coronary syndromes (ACS). Other dosing or oral administration of acetylsalicylic acid (ASA) – within the frame of the new European Society of Cardiology (ESC) guidelines – may also (more ...)PRE-HOSPITAL EMERGENCY MEASURESThe first priority is to alert emergency services – whatever emergency number applies geographically. In addition to general measures including an ECG (ideally taken during the first medical contact at the patient’s home), the key is the immediate antithrombotic therapy: if possible (independent of any history of pre-existing therapy), acetylsalicylic acid (ASA) 500 mg and (unless contraindicated) an injection of 5,000 IU of unfractionated heparin should be immediately administered. Other dosing o