Device therapies in cardiorenal syndrome: an expert review

Managing cardiorenal syndrome in acute decompensated heart failure remains a major challenge in contemporary cardiology. While pharmacological decongestion with diuretics is the cornerstone of therapy and is effective in most patients, worsening renal function and diuretic resistance continue to pose challenges in selected cases. Device-based therapies are increasingly explored to target key pathophysiological mechanisms underlying cardiorenal dysfunction. This expert review builds on a conceptual framework for device-based therapies. Rather than cataloguing individual technologies, we apply a functional framework that classifies devices according to their primary mode of action: reduction of venous or lymphatic congestion ('pullers'), augmentation of arterial perfusion ('pushers'), and direct removal of sodium and/or fluid ('removers'). For each category, we integrate pathophysiological rationale with available clinical evidence, highlighting the predominance of early-phase physiological evidence and the need for randomized studies demonstrating benefit beyond optimized contemporary medical care.