Usefulness of Hyperventilation Thallium-201 Single Photon Emission Computed Tomography for the Diagnosis of Vasospastic Angina.

Abstract

SUMMARYTo establish a safe and sensitive diagnostic procedure for detecting coronary vasospasm, we utilized 201-thallium myocardial SPECT combined with hyperventilation (HV-SPECT) in 29 patients with vasospastic angina (VAP) and 11 controls.Twenty-five of 29 patients with VAP and 5 of 11 controls developed transient perfusion defects on HV-SPECT, resulting in a sensitivity and specificity calculated at 86% and 55%, respectively.Overall accuracy in identifying corresponding vessels with coronary vasospasm was 67%; it was 83%, 75% and 42% for patients with 1, 2 and 3 vessel spasm, respectively. Coronary vasospasm tended to be identified more accurately in the left anterior descending branch and the right coronary artery than in the circumflex branch (75%, 71% and 50%, respectively).The hyperventilation test induced ischemic ECG changes in 11 of 29 patients with VAP, yielding a sensitivity of 38%. Analyzing the washout rate of HV-SPECT in patients with VAP, both the extent and severity scores of patients with ischemic ECG changes were larger than those of patients without. No serious complications occurred during HV-SPECT.In conclusion, HV-SPECT was a safe and sensitive procedure as a primary diagnostic approach for VAR From the results of washout analysis, HV-SPECT could detect more mild myocardial ischemia than could the ECG, and seemed quite useful especially for detecting coronary vasospasm accompanied by minimal ischemic ECG changes. (Jpn Heart J 36: 405-420, 1995)

Phase changes caused by hyperventilation stress in spastic angina pectoris analyzed by first-pass radionuclide ventriculography

“…This relatively low correlation might be caused by: 1) a relatively poor signal-to-noise ratio of first-pass images in method, 2) the geometrical difference due to RAO and LAO projection generated different segment values. This segment difference was also reported in regional LVEF studies by Papapietro et al' 8 After HV stress test, EF decreased in 69% of patients with vasospastic angina. This result supports the finding of reduced LV wall motion after HV stress reported in previous studies.7 ' 9 In CAD patients a relationship between EF decrease and SD increase in stress tests has been reported.…”

“…[7][8][9] The response of left ventricular (LV) ejection fraction (EF) to HV stress has been reported to be sensitive for identifying coronary spasm and its sensitivity ranged from 66.7% to 74% in patients with spastic angina. 7 '9 Phase analysis which can demonstrate LV contraction sequence, is used to detect various abnormalities in interventricular electrical conduction and ischemic heart dis -e a s e s .…”

Clinical usefulness of myocardial scintigraphy in patients with vasospastic angina

“…Cardiologists employ hyperventilation-Tl myocardial scintigraphy to diagnose coronary spasm. As shown in Table 1, in 57 patients with VSA, 41 (71.9%) patients had abnormal scintigraphic findings during hyperventilation-Tl [24][25][26]. Sensitivity was 64.9%, while discordance was observed in 4 patients (7%).…”

Hyperventilation testing in the diagnosis of vasospastic angina: A clinical review and meta‐analysis

“…Of the 16 studies included, 7 (44%) provided enough information to assess accuracy based on sex, yielding a total of 271 males (262 with VSA, 97%) and females (66 with VSA, 84%): 7 reported on ECG, 45,[49][50][51][52][53]55 2 on TTE, 49,50 and 3 on MPI [51][52][53] (Table S2). Pooled sensitivity for all modalities combined were 90% (95% CI: 75%-97%, i 2 = 0.65) for males and 78% (95% CI: 52%-92%, i 2 = 0) for females.…”