Angiography derived index of microvascular resistance (IMR) in Takotsubo syndrome

Abstract Background and purpose Coronary microvascular dysfunction (CMD) has been proposed as a key driver in the etiopathogenesis of Takotsubo syndrome (TTS), likely related to an “adrenergic storm” upon susceptible circulation. The aim our manuscript was assess quantify CMD patients with TTS through angiography-derived index microcirculation (IMR) evaluate its correlation clinical presentation. Methods angiograms 41 consecutive were retrospectively offline analyzed derive angiography-based indices CMD. Three recently developed (NH-IMRangio, AngioIMR A-IMR) calculated compared based on Quantitative Flow Reserve (QFR) analysis. defined IMRangio ≥25 units. between presentation outcomes then assessed. Results Median age 76 years, 85.7% women mean left ventricular ejection fraction (LVEF) at first echocardiogram 41.2%. Angiography-derived IMR higher Left Anterior Descending artery (LAD) than Circumflex (LCX) Right (RCA) either NH-IMRangio (52.7 vs 35.3 41.4), (47.2 31.8 37.3) or A-IMR 36.1 41.8). All presented least one territory each formula. LAD significantly presenting LVEF impairment (≤40%) those preserved global function (NH-IMRangio: 59.3 46.3, p. value=0.030; AngioIMR: 52.9 41.4, p-value=0.037; A-IMR: 59.2 p-value=0.035). Conclusion CMD, assessed IMR, is common finding it inversely correlated LV function. available formulas have substantial superimposable diagnostic performance assessing coronary Funding Acknowledgement Type funding sources: None.