title: Hemodynamic and intravascular ultrasound assessment of myocardial bridging: fractional flow reserve paradox with dobutamine versus adenosine.
abstract: Compared to coronary angiography, both intravascular ultrasound (IVUS) and CT-angiography provide important information with respect to the morphological aspects of myocardial bridging (MB). However, these modalities are limited in defining the hemodynamic and clinical significance of MB. Intracoronary Doppler studies demonstrate a peculiar abnormal Doppler flow profile associated with MB. Fractional flow reserve (FFR) after adenosine infusion has been used to assess the hemodynamic significance of MB, but FFR after adenosine induced hyperemia underestimates the significance of MB. On the other hand, high-dose dobutamine by increasing the contractility of the bridging segment unmasks ischemia induced by MB. This review outlines the role of flow velocity measurement by intracoronary Doppler, FFR, and IVUS for assessment of patients with MB. In addition, we compared FFR measurements after adenosine versus dobutamine infusions for the hemodynamic assessment of MB in two patients.
authors.affiliation: Division of Cardiology, University of Cincinnati School of Medicine, Cincinnati, Ohio 45267, USA.
authors.forename: Abdul
authors.initials: A
authors.lastname: Hakeem
authors.forename: Mehmet
authors.initials: M
authors.lastname: Cilingiroglu
authors.forename: Massoud A
authors.initials: MA
authors.lastname: Leesar
mesh_terms: D000241:Adenosine / Q000008:administration & dosage; D000328:Adult; D015906:Angioplasty, Balloon, Coronary / Q000295:instrumentation; D001783:Blood Flow Velocity; D017023:Coronary Angiography; D004280:Dobutamine / Q000008:administration & dosage; D054855:Drug-Eluting Stents; D015150:Echocardiography, Doppler; D053805:Fractional Flow Reserve, Myocardial; D006439:Hemodynamics; D006801:Humans; D007262:Infusions, Intravenous; D008297:Male; D008875:Middle Aged; D054084:Myocardial Bridging / Q000175:diagnosis* / Q000000981:diagnostic imaging / Q000503:physiopathology / Q000628:therapy; D011237:Predictive Value of Tests; D012720:Severity of Illness Index; D016896:Treatment Outcome; D018084:Ultrasonography, Interventional
chemical_list: D004280:Dobutamine; D000241:Adenosine