Microwave Ablation for Twin Reversed Arterial Perfusion Sequence: A Novel Frontier in Minimally Invasive Perinatology – Integrating Literature Review with First Case Insights

Abstract Twin reversed arterial perfusion (TRAP) sequence is a rare but severe complication of monochorionic twinning, in which retrograde arterial perfusion of an acardiac twin places the pump twin at risk of high-output cardiac failure, polyhydramnios, and preterm birth. While established intrauterine therapies include radiofrequency ablation (RFA), bipolar cord occlusion, and fetoscopic laser, the role of microwave ablation (MWA) remains incompletely defined. We conducted a systematic review following Preferred Reporting Items for Systematic Reviews and Meta-analyses 2020 guidelines, complemented by a contemporary case experience, to evaluate the feasibility, outcomes, and challenges of MWA for the TRAP sequence. Searches of PubMed, Scopus, Web of Science, and Cochrane Library to December 2024 identified 249 records, of which 45 met the inclusion criteria and 20 were appraised as high-quality evidence. Across reports, MWA consistently achieved Doppler-confirmed intrafetal flow cessation, with procedural feasibility comparable to RFA. Potential advantages included broader and more uniform ablation zones with shorter application times. However, the evidence base remains limited, dominated by case reports and small series without randomized controlled trials. Procedural heterogeneity, including variation in antenna gauge, wattage, and cycle protocols, complicates comparability. Reporting standards are inconsistent, with frequent omission of maternal safety outcomes, neurodevelopmental follow-up, and long-term results. Accessibility is uneven, as expertise and equipment are concentrated in high-resource centers, and ethical dilemmas regarding the timing of intervention and parental counseling remain underexplored. We also report a 22-week TRAP case treated successfully with ultrasound-guided MWA (15G antenna, 60 W × 3 min, then 40 W × 1 min × 4 cycles), achieving complete vascular occlusion and stable pump twin heart rate (143 bpm). Our findings suggest that MWA is a promising but still experimental frontier in minimally invasive perinatology. Multicenter trials, harmonized procedural frameworks, and ethically informed counseling models are urgently needed to define its role in global practice.