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🌱 來自: diagram of acute coronary syndromes

What is the general approach to the treatment of acute coronary syndromes without ST-segment elevation?

A: Once a definite or likely diagnosis of an acute coronary syndrome without ST-segment elevation has been made, the patient is triaged to either an invasive strategy or an ischemia-guided strategy (i.e., an initial medical strategy with angiography reserved for evidence of spontaneous or provoked ischemia). An invasive strategy leads to improved outcomes and is favored for the majority of patients; the urgency of angiography (performed with the goal of revascularization) depends on the presence or absence of high-risk features. If initial medical therapy stabilizes the patient’s hemodynamic condition and relieves ischemic discomfort, angiography can proceed within 12 to 24 hours. An even more delayed approach (with angiography performed within 25 to 72 hours) is an option for patients at low immediate risk. In patients whose condition is unstable, urgent PCI is performed, as it is for patients with STEMI.

Table 1. Six Initial Assessment and Management Decisions Pertaining to Patients Presenting with Chest Pain and a Possible Acute Coronary Syndrome.*

1. Triage to an acute coronary syndrome pathway (STEMl, non-STEML, possible or probable unstable angina, or nonischemic disorder) on the basis of the history, examination, ECG, and cardiac troponin test result.
2. Assess risk of cardiovascular death or recurrent ischemia (high, intermediate, Or low risk) on the basis of clinical features, ECG, and troponin testing; an integrated risk score (e.g., TIMI Or GRACE score) can be used.
3. Initiate general care: limit activity; administer aspirin, nitroglycerin, and a statin, consider ad ministration of oxygen, beta-blocker, or morphine.
4. Choose invasive or noninvasive (ischemia-guided) initial strategy; the choice ofearly invasive management is based on risk and patient’s preferences.
5. Select a second antiplatelet agent to add to aspirin (P2Yiz inhibitor or glycoprotein Ilb/llla inhibitor), with selection based on thrombotic risk, timing of invasive strategy, likelihood of need for surgical revascularization, and risk of bleeding.
6. Choose an anticoagulant agent (unfractionated heparin, low-molecularweight heparin, fondaparinux, or bivalirudin) according to the initial management strategy (invasive or noninvasive) and risk of bleeding.t

Q: How are stenoses in nonculprit coronary arteries managed in patients undergoing PCI for ST-segment elevation myocardial infarction? A: An ongoing controversy in the use of PCI for STEMI is the approach to stenoses in nonculprit coronary arteries. PCI of nonculprit stenoses has been contraindicated on the basis of observational studies, which are subject to selection bias. More recently, three randomized trials with samples of intermediate size (296 to 627 patients) showed reductions in ischemia-driven revascularization and variable effects on the risks of recurrent myocardial infarction and death with PCI of nonculprit stenosis. A 2015 systematic review of five trials involving a total of 1568 patients confirmed a decreased risk of repeat revascularization (relative risk, 0.36; 95% confidence interval [CI], 0.27 to 0.48) and a lower risk of nonfatal myocardial infarction (relative risk, 0.58; 95% CI, 0.36 to 0.93), with an uncertain effect on the risk of death (relative risk, 0.82; 95% CI, 0.53 to 1.26). On the basis of this evidence, PCI of nonculprit lesions may be considered either at the time of primary PCI in hemodynamically stable patients or as a staged procedure (ACC–AHA class IIb recommendation, level of evidence B).