What is the management approach for STEMI (ST-Elevation Myocardial Infarction) with suspected right ventricular involvement, as indicated by ST elevation in right-sided leads V1r, V2r, and V3r?

Management of STEMI with Right Ventricular Involvement (ST Elevation in V1R, V2R, V3R)

Patients with inferior STEMI showing ST elevation in right-sided leads V3R and V4R have right ventricular infarction and require immediate reperfusion with primary PCI as the preferred strategy, combined with aggressive IV fluid resuscitation while strictly avoiding vasodilators including nitrates, opioids, diuretics, and ACE-inhibitors. 1

Diagnostic Confirmation

• Record right precordial leads (V3R and V4R) in all patients with inferior STEMI, as ST elevation ≥0.5 mm (≥1 mm in men <30 years) in these leads confirms right ventricular involvement 1, 2

• The clinical triad of hypotension, clear lung fields, and elevated jugular venous pressure in a patient with inferior STEMI is specific but insensitive for RV infarction 1

• Q-waves and ST elevation in standard leads V1-V3 also suggest right ventricular infarction 1

• Echocardiography should be performed to confirm RV dysfunction and assess the degree of involvement 1

• ST elevation in ≥2 right precordial leads identifies hemodynamically significant RV infarction requiring aggressive management 3

Critical Management Principles

Immediate Reperfusion Strategy

• Primary PCI should be performed as soon as possible as it may result in rapid hemodynamic improvement and is the preferred reperfusion strategy 1

• Fibrinolytic therapy is appropriate in hypotensive patients if PCI is not immediately available, despite some uncertainty about its effectiveness in isolated RV infarction 1

Hemodynamic Management - The Key Differentiator

• Maintain right ventricular preload through rapid IV fluid loading - this is the cornerstone of RV infarction management and differs fundamentally from LV-predominant STEMI 1

• Administer IV fluids rapidly initially, with careful hemodynamic monitoring during fluid administration 1

• Strictly avoid all vasodilator medications including:

  • Opioids (morphine)
  • Nitrates
  • Diuretics
  • ACE-inhibitors and ARBs 1

Arrhythmia Management

• Promptly correct atrial fibrillation as atrial contribution to RV filling is critically important in this context 1

• Institute dual chamber pacing immediately if heart block develops, as AV synchrony is essential for maintaining adequate RV filling and cardiac output 1

• Initiate ECG monitoring immediately to detect life-threatening arrhythmias 1

Common Pitfalls and How to Avoid Them

• Pitfall #1: Treating RV infarction like standard LV infarction with nitrates and diuretics - this causes catastrophic hypotension. Instead, give IV fluids aggressively 1

• Pitfall #2: Failing to record right-sided leads in inferior STEMI - always obtain V3R and V4R in any inferior MI to identify the 40-50% who have RV involvement 1, 2

• Pitfall #3: Delaying cardioversion of atrial fibrillation - loss of atrial kick is poorly tolerated and should be corrected immediately 1

• Pitfall #4: Administering standard STEMI medications (ACE-inhibitors, nitrates) reflexively - these are contraindicated in hemodynamically significant RV infarction 1

Prognostic Considerations

• RV infarction may manifest as cardiogenic shock, but the treatment strategy differs fundamentally from shock due to severe LV dysfunction 1

• Patients with ST elevation in ≥2 right precordial leads have a more complicated hospital course characterized by bradyarrhythmias, hypotension, cardiogenic shock, and higher mortality 3

• The presence of clinical signs (raised JVP 65%, Kussmaul's sign 45%, hypotension 40%, right-sided S3 25%) combined with ST elevation in ≥2 right precordial leads identifies hemodynamically significant RV infarction even without advanced monitoring 3