+++
CHAPTER SUMMARY FROM THE PHARMACOTHERAPY HANDBOOK
++
For the Chapter in the Schwinghammer Handbook, please go to Chapter 5, Acute Coronary Syndromes.
++
KEY CONCEPTS
The cause of acute coronary syndrome (ACS) in more than 90% of patients is the acute rupture, fissure, or erosion of an unstable atherosclerotic plaque followed by subsequent thrombus formation that impairs distal blood flow resulting in acute myocardial ischemia.
Patients with symptoms of myocardial ischemia suspected of having ACS should undergo risk stratification that incorporates their past medical history, presenting signs and symptoms, 12-lead electrocardiogram (ECG), and cardiac troponin (cTn); dynamic elevation in serial cTn values confirms the diagnosis of myocardial infarction (MI).
Intravenous (IV) nitroglycerin should be considered to alleviate anginal pain and/or treat acute comorbidities such as uncontrolled hypertension (HTN) or heart failure (HF), oxygen should be administered to patients with hypoxia (oxygen saturation less than 90% [0.90]), and IV morphine may be considered in patients with refractory anginal pain.
In the absence of contraindications, an oral β-blocker should be initiated for all patients with ACS and continued for 3 years or more to reduce the risk of major adverse cardiac events (MACE); calcium channel blockers (CCBs) may be considered in patients with vasospasm and those refractory to or with contraindications or intolerance to β-blockers.
Reperfusion of the infarct-related artery in ST-segment elevation myocardial infarction (STEMI) with primary percutaneous coronary intervention (PCI) within 90 minutes of first medical contact is preferred to fibrinolytic therapy unless primary PCI cannot be performed within 120 minutes of presentation.
Antiplatelet therapy is a central component to the acute and chronic management of patients with ACS to reduce MACE, frequently includes aspirin plus a P2Y12 inhibitor, and requires careful attention paid to the clinical scenario to select the regimen that optimizes efficacy and safety.
Use of parenteral anticoagulant agents (unfractionated heparin, low-molecular-weight heparin [LMWH], fondaparinux, bivalirudin) during hospitalization have the ability to reduce MACE in patients with ACS and requires knowledge of the diagnosis, selected management strategy, and other factors to select the drug and dosing regimen that optimize efficacy and safety.
Dual antiplatelet therapy (DAPT) with aspirin plus a P2Y12 receptor inhibitor is indicated for all patients post-ACS for a minimum of 12 months regardless of whether the patient is managed with an ischemia-driven approach or if the patient undergoes revascularization.
All patients post-ACS should receive maximally tolerated high-intensity statin therapy to reduce the risk of MACE; patients with low-density lipoprotein cholesterol (LDL-C) of 70 mg/dL (1.81 mmol/L) or greater on maximally tolerated high-intensity statin therapy should be considered for the addition of nonstatin therapies (eg, ezetimibe, proprotein convertase subtilisin kexin 9 [PCSK9] inhibitor).
To reduce the risk of MACE, all post-MI patients should receive oral treatment with an angiotensin-converting enzyme inhibitor (ACEI) or angiotensin receptor blocker (ARB) unless contraindicated and a mineralocorticoid receptor antagonist if the left ventricular ejection fraction (LVEF) is 40% (0.40) or less ...