A patient with restrictive cardiomyopathy experiences increasing dyspnea and jugular venous distension. Which nursing action is prioritized to address these symptoms?

Restrictive cardiomyopathy is characterized by increased myocardial stiffness, impaired ventricular compliance, and diastolic dysfunction, leading to elevated ventricular filling pressures, systemic and pulmonary venous congestion, and clinical signs such as dyspnea and jugular venous distension due to fluid backup. Rationale: A. High-dose glucocorticoid therapy is only indicated in specific inflammatory or infiltrative causes of restrictive cardiomyopathy (such as sarcoidosis). It does not provide immediate relief of volume overload or venous congestion and is not an acute symptomatic management intervention. B. Increased fluid intake worsens venous congestion by elevating intravascular volume and further increasing preload, which the stiff ventricle cannot accommodate. This exacerbates dyspnea and jugular venous distension. C. Diuretics reduce intravascular volume and lower venous and pulmonary congestion, directly decreasing preload and relieving symptoms such as dyspnea and JVD. This is the most appropriate and immediate intervention for symptomatic relief. D. Increasing dietary sodium promotes fluid retention, worsening systemic and pulmonary congestion. This increases venous pressure and exacerbates symptoms of heart failure physiology in restrictive cardiomyopathy.