Contemporary Mechanical Support Devices for Temporary and Long-Term Applications

<b>Background</b>: Mechanical circulatory support (MCS) has revolutionized advanced heart failure and cardiogenic shock management, yet randomized controlled trials have failed to demonstrate consistent mortality benefits with temporary devices, and outcomes remain highly variable across institutions. <b>Methods</b>: This narrative review examines contemporary MCS devices, analyzing their hemodynamic principles, clinical outcomes, complications, and selection strategies. The published literature addressing MCS clinical applications and outcomes was reviewed, with reference lists examined to identify additional sources. <b>Results</b>: Temporary MCS devices demonstrate a persistent hemodynamic-survival paradox where improved hemodynamics fail to translate into mortality benefits in randomized trials. This disconnect reflects delayed intervention after irreversible organ damage, device complications offsetting hemodynamic gains, heterogeneous patient selection without phenotyping, timing challenges, and inadequate statistical power. Landmark trials provide definitive evidence against routine early VA-ECMO use, showing no survival advantage while significantly increasing complications. Optimal device selection requires integrating hemodynamic phenotyping with shock stage to match devices to pathophysiology, while biventricular failure presents the greatest challenge with substantially lower survival. For durable devices, third-generation systems demonstrate superior outcomes with dramatically reduced pump thrombosis and improved survival. Critically, multidisciplinary shock teams employing standardized protocols significantly reduce mortality beyond what devices alone achieve, with structured programs showing substantially improved survival compared to trials using similar devices without organized care systems. <b>Conclusions</b>: Mechanical circulatory support has transformed heart failure management, but optimal outcomes require integrating devices within structured care delivery systems. Success depends on comprehensive hemodynamic assessment, multidisciplinary team activation, protocolized device selection, standardized escalation and weaning strategies, and regionalized networks. The future lies in shifting focus from device innovation to implementation science, establishing quality metrics, developing precision medicine approaches, and conducting trials in phenotype-selected populations with protocolized care. This systems-of-care paradigm offers the most promising path toward translating technological advances into sustained mortality reduction.