Abstract 3668: Usefulness of a Novel Dual-Sensor (Pressure and Doppler Velocity) Guidewire for the Evaluation of Coronary Microvascular Impairments in Patients with Diabetes Mellitus
[Background] The technique to estimate the degree of coronary microvascular impairment in patients with diabetes mellitus(DM) was limited in the daily practice.
[Methods and Results] We enrolled 20 patients with a stenosis in the left anterior coronary discending artery, and 10 patients were combined with DM. A novel 0.014-inch dual-sensor (pressure and Doppler velocity) guidewire was placed in the distal portion to the stenosis to take coronary artery pressure and flow velocity simultaneously. Fractional flow reserve (FFR), coronary flow reserve (CFR) and minimal microvascular resistance (MVR) index calculated as the distal mean pressure divided by the distal averaged peak flow velocity were obtained during maximal hyperemia. The peak flow velosity was plotted against the coronary pressure, and the pressure at zero flow (Pzf) was calculated from the slope of the flow-pressure relation inthe phase of diastolic flow decrease. FFR (0.51 vs. 0.49, ns) and CFR (1.4 vs. 1.6, ns) were not different between DM and non-DM patients before PCI, and those were increased significantly after PCI. After successful PCI, FFR (0.91 vs. 0.94, ns) was similar in both groups, but CFR in DM patients was significantly lower than that in non-DM patients (2.4 vs. 3.6, p<0.05). MVR and Pzf were not changed before and after PCI, and they were significantly higher in DM patients (MVR; 3.1 vs.1.4, p<0.05, Pzf; 16 vs. 33 mmHg, p<0.05)
[Conclusion] Simultaneous assessment of coronary artery pressure and flow velocity with a dual-sensor guidewire might be useful to evaluate coronary microvascular resistance, and the present study clarifies the existence of coronary microvascular impairments in patients with DM.