What does the ELNT regimen entail for a patient with rheumatic heart disease, mitral‑valve replacement, atrial fibrillation, and acute pulmonary edema?

ELNT Regimen for Rheumatic Mitral-Valve Replacement with Atrial Fibrillation

For a patient with rheumatic heart disease, mitral-valve replacement (bioprosthetic), atrial fibrillation, and acute pulmonary edema, the ELNT regimen consists of: Enalapril (or ACE inhibitor), Lasix (furosemide), Nitrates, and Therapeutic anticoagulation with warfarin targeting INR 2.5 (range 2.0-3.0).

Anticoagulation Strategy (The "T" in ELNT)

Warfarin is the only acceptable anticoagulant for this patient—direct oral anticoagulants (DOACs) are absolutely contraindicated in rheumatic valve disease with atrial fibrillation. 1, 2

• Target INR is 2.5 with acceptable range 2.0-3.0 for rheumatic mitral disease with atrial fibrillation. 2, 3, 4
• DOACs (apixaban, rivaroxaban, dabigatran, edoxaban) are contraindicated because rheumatic etiology was an exclusion criterion in all pivotal NOAC trials. 1
• The 2019 AHA/ACC/HRS guidelines explicitly classify rheumatic mitral disease with AF as "valvular AF" requiring vitamin K antagonist therapy, not DOACs. 2, 4
• Even after bioprosthetic mitral valve replacement for rheumatic disease, warfarin remains preferred over DOACs because the atria remain large and severely diseased from the rheumatic process. 1
• Recent evidence (INVICTUS trial, 2022) demonstrated that rivaroxaban led to higher cardiovascular events and death compared to warfarin in rheumatic heart disease-associated AF. 5

Warfarin Dosing and Monitoring

• Initiate warfarin at 2-5 mg daily; avoid loading doses to minimize hemorrhagic complications. 2
• Check INR weekly during initiation, then monthly once stable in therapeutic range. 2, 4
• Reassess renal and hepatic function at least annually to ensure continued safety. 2

Diuretic Therapy (The "L" in ELNT)

Furosemide (Lasix) is the cornerstone of acute pulmonary edema management in this setting, addressing the volume overload that precipitated the crisis.

• Intravenous loop diuretics should be administered immediately for acute pulmonary edema, with careful monitoring to avoid excessive preload reduction that could compromise cardiac output across any residual mitral pathology. 1, 6
• Maintain preload at a level high enough to allow adequate forward cardiac output but low enough to prevent recurrent pulmonary edema—this requires measurement of cardiac output and pulmonary wedge pressure in complex cases. 1
• Judicious fluid management is critical; excessive diuresis can precipitate hypotension and inadequate organ perfusion, while insufficient diuresis risks recurrent pulmonary edema. 1

ACE Inhibitor Therapy (The "E" in ELNT)

Enalapril or another ACE inhibitor provides afterload reduction and neurohormonal blockade, particularly important in patients with heart failure and atrial fibrillation.

• ACE inhibitors are Class I, Level A recommendation for patients with heart failure and reduced ejection fraction as part of guideline-directed medical therapy. 1
• Afterload reduction is particularly beneficial in regurgitant valve lesions (if any residual mitral regurgitation exists) by favoring forward flow. 1
• Start at low doses and titrate upward while monitoring renal function and potassium, especially in patients on warfarin who may have dietary restrictions. 1

Nitrate Therapy (The "N" in ELNT)

Nitrates provide immediate preload and afterload reduction in acute pulmonary edema, complementing diuretic therapy.

• Intravenous nitroglycerin is preferred in the acute setting for rapid titration and immediate effect on pulmonary congestion. 1
• Nitrates reduce left atrial pressure and pulmonary capillary pressure, directly addressing the pathophysiology of pulmonary edema. 1
• Avoid excessive systemic hypotension, which can compromise coronary perfusion and precipitate arrhythmias or myocardial ischemia. 1
• Transition to oral nitrates (isosorbide mononitrate or dinitrate) once acute crisis resolves, with nitrate-free intervals to prevent tolerance. 1

Critical Hemodynamic Considerations

Atrial fibrillation with rapid ventricular response is particularly dangerous in rheumatic valve disease because shortened diastolic filling time increases left atrial pressure and precipitates pulmonary edema. 1, 3

Rate Control Strategy

• Target heart rate 60-80 bpm in patients with any degree of mitral stenosis (even post-replacement if stenosis was the original lesion) to maximize diastolic filling time. 3
• Beta-blockers (metoprolol, esmolol) or calcium-channel blockers (diltiazem) should be used for rate control in atrial fibrillation. 3
• Continue rate-control medications throughout the perioperative and recovery periods. 3
• Avoid agents that provoke tachycardia (ketamine, high-dose atropine, pancuronium). 3

Rhythm Considerations

• Maintain sinus rhythm whenever possible; atrial fibrillation markedly worsens hemodynamics in rheumatic valve disease. 3
• Postcardioversion pulmonary edema is a recognized complication in patients with rheumatic mitral valve disease and atrial fibrillation, occurring in 1-3% of cases with 18% mortality. 6
• If cardioversion is attempted, observe patients for at least 3 hours and counsel on development of respiratory symptoms, as pulmonary edema may occur up to 12 hours post-procedure. 6

Common Pitfalls and Management Strategies

Do not combine aspirin with warfarin at therapeutic INR (2.0-3.0) in this population—it increases bleeding risk without adding stroke protection. 4

• Aspirin monotherapy is grossly inadequate for stroke prevention in rheumatic valve disease with AF, reducing stroke risk by only 19% compared to 62% with warfarin. 4
• Aspirin should only be added in specific circumstances such as concurrent coronary artery disease or mechanical valve, not routinely for rheumatic disease. 4
• If a breakthrough embolic event occurs on low-intensity anticoagulation (INR <2.0), increase target INR to 3.0-3.5 rather than adding antiplatelet therapy. 4

Left Atrial Thrombus Management

• If transesophageal echocardiography identifies left atrial thrombus, increase warfarin intensity to target INR 3.0 (range 2.5-3.5) and maintain for 4-12 weeks before repeat imaging. 1, 3
• Any elective procedure must be postponed until thrombus resolution is documented. 1, 3

Perioperative Bridging (if surgery required)

• Use therapeutic-dose unfractionated heparin (IV) or low-molecular-weight heparin (subcutaneous) to bridge patients on warfarin who require surgery. 3
• Stop warfarin 5 days before procedure; initiate bridging when INR falls below 2.0. 3
• Discontinue UFH 4-6 hours before incision and LMWH 24 hours before. 3
• Resume therapeutic anticoagulation as soon as surgical hemostasis permits. 3

Monitoring and Follow-up

Invasive arterial blood pressure monitoring is strongly recommended for all patients with moderate-to-severe rheumatic heart disease during acute decompensation. 3

• Central venous pressure monitoring should be employed when ventricular function is compromised or in complex valve disease. 3
• Monitor closely for postoperative atrial fibrillation with rapid ventricular response, a common complication. 3
• Maintain strict fluid balance to prevent recurrent pulmonary edema. 3
• Noninvasive ventilation (BiPAP/CPAP) may be required for acute pulmonary edema management until diuresis and hemodynamic optimization are achieved. 6