Which intervention is most appropriate for a patient experiencing pulmonary congestion related to mitral valve regurgitation?

Mitral valve regurgitation causes retrograde blood flow, left atrial volume overload, pulmonary venous hypertension, and alveolar fluid accumulation, leading to impaired gas exchange, reduced oxygen diffusion capacity, and progressive respiratory distress with crackles and hypoxemia. Rationale: A. Strenuous exercise increases myocardial workload and worsens pulmonary congestion in valvular disease. It elevates oxygen demand beyond compromised cardiac output capacity. This can precipitate acute dyspnea and pulmonary edema. Activity must be carefully titrated in symptomatic patients. B. Anticoagulant therapy targets thromboembolism prevention, not fluid overload correction. It is indicated in atrial fibrillation or thrombus risk states. It does not reduce pulmonary congestion or improve valve incompetence. Therefore it is not immediate management for respiratory compromise. C. Diuretics reduce intravascular volume and decrease pulmonary capillary hydrostatic pressure effectively. This relieves alveolar fluid accumulation and improves oxygenation. They are first-line for symptomatic pulmonary congestion in valvular heart disease. This directly addresses fluid overload physiology. D. Total fluid restriction reduces circulating volume but is not definitive acute management. Severe restriction may worsen renal perfusion and neurohormonal activation. It is adjunctive rather than primary therapy in pulmonary congestion. Diuretics remain the immediate pharmacologic intervention.