Recovery from Kidney Failure Associated with Pulmonary Hypertension following Use of Vasodilators

Introduction: Pulmonary hypertension (PH) and kidney dysfunction are co-morbidities affecting patient outcomes. Chronic kidney disease (CKD) contributes to WHO group IV PH, while kidney injury frequently occurs in PH patients, indicating poor prognosis. The mechanisms involve cardiorenal syndrome and neurohormonal activation. Targeted therapies for PH may offer renal protective benefits, suggesting a beneficial approach for these conditions. We report a case of decompensated heart failure due to severe PH, resulting in acute kidney injury (AKI) from cardiorenal syndrome (CRS). The patient required continuous renal replacement therapy (CRRT) and experienced renal function normalization after vasodilator therapy. Case Description: A female in her 60s with severe tricuspid regurgitation and right-sided heart failure due to pulmonary hypertension presented with a two-week history of bilateral lower extremity edema and increased abdominal girth, indicating an acute exacerbation of right-sided heart failure. Initial intravenous diuretics led to suboptimal response and kidney injury from CRS. The patient developed shock, necessitating the cessation of diuretics. CRRT was started, followed by hemodialysis (HD). Concurrently, intravenous epoprostenol, oral sildenafil, and ambrisentan were administered, leading to the resolution of kidney failure. Discussion: The pathogenesis of CKD involves hemodynamic changes, inflammation, and oxidative stress, leading to glomerulosclerosis and kidney atrophy. PH-targeted therapies, including endothelin receptor antagonists (ERAs), phosphodiesterase type 5 inhibitors (PDE5Is), and prostacyclin analogues, influence kidney function due to their vasoactive properties. Sildenafil, a PDE5I, offers nephroprotective effects such as lowering blood pressure and reducing ischemia-reperfusion injury. The endothelin system, with its ET-A and ET-B receptors, plays a crucial role in vascular tone regulation. Selective ET-A blockade shows superior renal protection compared to dual ET-A/ET-B antagonism, as evidenced by preclinical and clinical studies. Prostanoids like epoprostenol demonstrate renal protective effects, improving outcomes in various kidney dysfunction contexts. Overall, these targeted therapies offer promising renal benefits in patients with PH and CKD.