From the Guidelines
Management of a suspected right-sided myocardial infarction (MI) with ECG changes indicating right-sided involvement requires prompt recognition and specific interventions, with the most recent guidelines from 2018 (1) emphasizing the importance of early reperfusion therapy and careful management of preload. Initial management includes obtaining a right-sided ECG to confirm the diagnosis, as standard 12-lead ECGs may not adequately show right ventricular involvement. Immediate treatment involves:
- Administering oxygen to maintain saturation above 94%
- Establishing IV access
- Providing aspirin (325 mg chewed) and anticoagulation with heparin Unlike typical left-sided MIs, patients with right-sided MI require:
- Aggressive fluid resuscitation with normal saline (1-2 L initially, then reassess) to maintain right ventricular preload, as these patients are preload-dependent
- Nitrates should be avoided or used with extreme caution as they can cause severe hypotension by reducing preload
- Inotropic support with dobutamine (starting at 2-5 mcg/kg/min) may be necessary if hypotension persists despite fluid administration Early cardiac catheterization and reperfusion therapy (PCI preferred over thrombolytics) should be pursued, targeting the likely culprit lesion in the right coronary artery, as recommended by the 2017 ESC guidelines (1). Hemodynamic monitoring is crucial, and temporary pacing may be needed as heart blocks are common, with the 2009 ACC/AHA guideline update (1) providing further guidance on the management of STEMI. This specialized approach is necessary because right ventricular dysfunction creates unique hemodynamic challenges that differ from left-sided MIs, requiring careful management of preload to maintain cardiac output, as highlighted in the 1996 ACC/AHA guidelines (1) and the 2009 AHA/ACCF/HRS recommendations (1).
From the Research
Right-Sided Myocardial Infarction (MI) Management
Changes on a 12-lead electrocardiogram (ECG) indicating right-sided involvement in a suspected myocardial infarction (MI) require prompt management. The following points outline the key considerations:
- Antiplatelet Therapy: Aspirin is recommended for all patients with suspected acute coronary syndrome (ACS) unless contraindicated, along with a second antiplatelet agent (e.g., clopidogrel, ticagrelor, or prasugrel) for most patients 2.
- Anticoagulation: Parenteral anticoagulation with unfractionated heparin, low-molecular-weight heparin, bivalirudin, or fondaparinux is recommended 2.
- Percutaneous Coronary Intervention (PCI): For patients with ST-segment elevation myocardial infarction (STEMI), PCI with stent placement should be performed as soon as possible. If PCI is delayed, fibrinolytic therapy should be considered 2, 3.
- Fibrinolytic Therapy: Fibrinolytic agents (e.g., streptokinase, alteplase, reteplase, or tenecteplase) are recommended for patients with STEMI and ST-segment elevation or left bundle-branch block on the ECG, if PCI is not immediately available 4.
- Prehospital Administration of Antiplatelet Agents: Prehospital administration of ticagrelor, a direct platelet P2Y12 receptor inhibitor, may provide better and earlier perfusion in patients with STEMI 5.
- Direct Ambulance Admission to the Cardiac Catheterization Laboratory: Direct admission from the ambulance to the catheterization laboratory can significantly reduce door-to-balloon times in primary PCI 6.
Key Considerations for Right-Sided MI
- ECG Changes: Changes on the 12-lead ECG indicating right-sided involvement, such as ST-segment elevation in leads V1-V4, may require specific considerations for management.
- Right Ventricular Involvement: Right ventricular involvement may occur in patients with right-sided MI, requiring careful assessment and management of hemodynamics.
- Adjunctive Therapy: Adjunctive therapy, such as statins, angiotensin-converting enzyme inhibitors, beta blockers, nitroglycerin, and morphine, may be considered for patients with right-sided MI, as per standard ACS management guidelines 2.