Transcatheter pulmonary flow restriction in congenital heart disease: evolving concepts and future perspectives

Pulmonary artery banding (PAB) remains an important palliative strategy in congenital heart disease (CHD), particularly for temporary modulation of pulmonary blood flow and pressure during staged management. Over the past two decades, catheter-based pulmonary flow restrictors (PFRs) have emerged as less invasive alternatives to surgery, expanding treatment options for fragile infants and selected older patients. This review traces the evolution of transcatheter PFR, from early experimental concepts to off-label use of manually fenestrated Medtronic microvascular plugs (MVPs). It examines device mechanics, fenestration geometry and technique, implantation strategies, pulmonary vascular interaction, complications, antithrombotic management, retrieval, and long-term limitations. Key challenges include non-standardized fenestration, device-vessel mismatch, progressive loss of restriction with growth, anatomy-dependent performance, and increasingly time-dependent retrieval difficulty. The principal strength of the MVP-based approach is its intraprocedural adaptability, allowing fenestration to be tailored to individual anatomy, hemodynamics, and therapeutic goals. Given the dynamic and heterogeneous physiology of CHD, future dedicated platforms should preserve this adaptability rather than impose a fixed design. Technical refinement should therefore remain embedded within a patient-centered strategy that allows ongoing adjustment. Multicenter registries and purpose-built platforms may help define the future of controlled and durable transcatheter pulmonary flow modulation.