The no-reflow phenomenon: current treatment and prevention strategies

   The no-reflow phenomenon remains a significant challenge in the management of myocardial infarction, despite advances in reperfusion therapy, including widespread use of primary percutaneous coronary intervention (PCI). This condition, characterized by inadequate microcirculation following the restoration of coronary blood flow, significantly worsens clinical outcomes by increasing the risk of heart failure and mortality. The advent of advanced diagnostic modalities, such as magnetic resonance imaging (MRI) and dynamic myocardial scintigraphy, has enabled more precise assessment of microcirculatory disturbances, offering a better understanding of the mechanisms underlying no-reflow and facilitating targeted prevention strategies. Preventive measures include prolonged stent ballooning, antithrombotic agents (e. g., IIb/IIIa inhibitors and intracoronary thrombolysis), and the use of nicorandil. Nicorandil, with its vasodilatory and cytoprotective properties, has shown promising results in improving angiographic and surrogate markers of reperfusion. However, treating established no-reflow remains a formidable challenge, as current interventions primarily improve surrogate markers (e.g., TIMI flow and ST-segment resolution) without significantly affecting long-term clinical outcomes. The most effective treatments for refractory no-reflow include nicorandil and epinephrine, with the latter demonstrating robust coronary vasodilation and improved coronary blood flow, as well as a reduction in microvascular obstruction volume. Future research directions involve the exploration of monoclonal antibodies capable of selectively blocking key inflammatory pathways and the use of hyperoxemic reperfusion. Nonetheless, additional clinical trials are required to confirm the efficacy and safety of these approaches. Thus, the search for optimal therapeutic solutions for managing no-reflow remains a critical priority, demanding further investigation to improve outcomes for myocardial infarction patients.

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