ABSTRACT
BACKGROUND: The Angiographic Microvascular Resistance (AMR), derived from a solitary angiographic view, has emerged as a viable substitute for the Index of Microcirculatory Resistance (IMR). However, the prognostic significance in ST-Segment Elevation Myocardial Infarction (STEMI) patients is yet to be established. This research endeavors to explore the prognostic capabilities of AMR in patients diagnosed with STEMI. METHODS: In this single-center, retrospective study, 232 patients diagnosed with STEMI who received primary Percutaneous Coronary Intervention (PCI) were recruited from January 1, 2018, to June 30, 2022. Utilizing the maximally selected log-rank statistics analysis, participants were divided into two cohorts according to an AMR threshold of 2.55 mmHg*s/cm. The endpoint evaluated was a composite of all-cause mortality or hospital readmission due to heart failure. RESULTS: At a median follow-up of 1.74 (1.07, 3.65) years, the composite endpoint event was observed in 28 patients within the higher AMR group and 8 patients within the lower AMR group. The higher AMR group showed a significantly higher risk for composite outcome compared to those within the low-AMR group (HRadj: 3.33; 95% CI 1.30â8.52; p = 0.03). AMR ≥ 2.55 mmHg*s/cm was an independent predictor of the composite endpoint (HR = 2.33; 95% CI 1.04â5.21; p = 0.04). Furthermore, a nomogram containing age, sex, left ventricle ejection fraction, post-PCI Quantitative Flow Ratio (QFR), and AMR was developed and indicated a poorer prognosis in the high-risk group for STEMI patients at 3 years. (HR=4.60; 95% CI 1.91â11.07; p < 0.01). CONCLUSIONS: AMR measured after PCI can predict the risk of all-cause death or readmission for heart failure in patients with STEMI. AMR-involved nomograms improved predictive performance over variables alone.
Subject(s)
Coronary Angiography , Microcirculation , Percutaneous Coronary Intervention , ST Elevation Myocardial Infarction , Vascular Resistance , Humans , ST Elevation Myocardial Infarction/diagnostic imaging , ST Elevation Myocardial Infarction/physiopathology , ST Elevation Myocardial Infarction/mortality , ST Elevation Myocardial Infarction/surgery , Female , Male , Middle Aged , Retrospective Studies , Prognosis , Aged , Microcirculation/physiology , Vascular Resistance/physiology , Risk Factors , Predictive Value of TestsABSTRACT
Introducción: La revascularización mediante intervención coronaria percutánea con colocación de stent, o cirugía de derivación coronaria, alivia la isquemia miocárdica. Sin embargo, las pruebas de estrés no invasivas y la angiografía coronaria no siempre proporcionan la información adecuada sobre la importancia funcional de las estenosis en las arterias coronarias. Objetivo: Describir las recomendaciones actuales de la literatura médica con respecto a la fisiología coronaria en la cardiopatía isquémica. Desarrollo: El índice de reserva fraccional de flujo se considera el estándar de oro para detectar la isquemia miocárdica. Su naturaleza invasiva se equilibra con la resolución espacial inigualable y su relación lineal con el flujo sanguíneo máximo. Los resultados clínicos de pacientes cuya estrategia de revascularización se basa en mediciones de reserva fraccional de flujo son decisivos en varios subconjuntos de diferentes lesiones. En la última década se ha propuesto la evaluación de la gravedad de la estenosis coronaria mediante índices no hiperémicos. Sin embargo, la precisión de estos índices para distinguir correctamente la isquemia miocárdica es solo del 80 %. Conclusiones: Actualmente, la hiperemia máxima se recomienda para una óptima toma de decisiones sobre la revascularización.
Introduction: Revascularization by percutaneous coronary intervention with stenting, or coronary bypass surgery, alleviates myocardial ischemia. However, noninvasive stress testing and angiography do not always provide adequate information on the functional significance of coronary artery stenoses. Objective: To describe the recommendations of the medical literature regarding coronary physiology in ischemic heart disease. Development: The fractional flow reserve index is considered the gold standard for detecting myocardial ischemia. Its invasive nature is balanced by unmatched spatial resolution and its linear relationship to peak blood flow. The clinical outcomes of patients whose revascularization strategy is based on fractional flow reserve measurements are decisive in several subsets of other lesions. In the last decade, assessment of coronary stenosis severity by non-hyperemic indices has been proposed; however, the accuracy of these indices to correctly distinguish myocardial ischemia does not exceed 80%. Conclusions: Currently, maximal hyperemia is recommended for optimal revascularization decision making.
ABSTRACT
Background: ST-segment elevation myocardial infarction (STEMI) has traditionally been managed with immediate reperfusion of the culprit artery, primarily through percutaneous coronary intervention and stent placement. Emerging data are highlighting the crucial importance of post-infarct microcirculatory function assessment. Case summary: This report presents a patient with an inferior STEMI who was successfully reperfused without stent implantation. Tools such as optical coherence tomography, fractional flow reserve, and positron emission tomography computed tomography N-13 ammonia were utilized, offering comprehensive insights into the anatomical and functional characteristics of both the epicardial vessel and microcirculation. Discussion: The recovery of the reversible component of microcirculatory dysfunction, observable as early as 5 days post-infarction, might carry significant implications for clinical decision-making. Such insights can potentially influence contemporary treatment strategies, including the consideration of deferred stenting. This case underscores the significance of post-infarct microcirculatory function and its potential impact on therapeutic approaches.