Abstract 17627: Is a Pressure Wire During the Spasm Provocation Useful for the Diagnosis of Vasospastic Angina?
Background: The spasm provocation test (SPT) is an important examination to diagnose vasospastic angina (VSA). However, complications such as prolonged hemodynamic instability can arise. On the other hand, although pressure wires have been widely used in assessing the severity of organic stenosis, no study has investigated whether the use of these wires during the SPT is helpful in establishing a diagnosis of VSA. Therefore, we performed the SPT using a pressure wire and compared the results with those from patients who underwent the same test without a pressure wire.
Methods: Forty-one patients (17 men; mean age, 68 years) underwent the SPT for the evaluation of chest symptoms. A pressure wire was used during the test in 18 of these patients (Group I), whereas the remaining 23 patients underwent the test without the wire (Group II). The pressure ratio of the distal lesion to the proximal lesion (Pd/Pa) was continuously monitored during the test. VSA was defined as >90% narrowing of the epicardial coronary arteries as observed on angiography during the SPT, accompanied by characteristic chest pain and/or ST-segment deviation on electrocardiography. Procedure-related parameters, namely fluoroscopic time, and frequency of hemodynamic instability, were investigated in both groups.
Results: Patient characteristics did not differ between the 2 groups. Fluoroscopic time tended to be longer in Group I than in Group II (13 ± 0.9 min vs. 11 ± 0.8 min, p = 0.0563). The pressure wire was successful placed in the distal portion of the RCA in 12 of 17 (71%) patients and in the distal portion of the LAD in 18 of 18 (100%) patients. Therefore, Pd/Pa was assessed adequately in 30 of 35 (86%) vessels in which the pressure wire was successfully placed. Minimal Pd/Pa during the SPT was 0.66 ± 0.03 in 19 vessels with spasm and 0.92 ± 0.04 in 11 vessels without spasm. The cut-off value for minimal Pd/Pa that indicated the presence of VSA was 0.82. The frequency of hemodynamic instability tended to be lower in Group I than in Group II (0% vs. 30%, p = 0.0566).
Conclusions: These findings suggest that the use of a pressure wire during the SPT may be helpful in establishing a firm diagnosis of VSA. In addition, it may provide key additional information to arrive at an accurate diagnosis.
- © 2013 by American Heart Association, Inc.