TITLE:
Can regadenoson pharmacologic SPECT be performed effectively in patients with left bundle branch block or paced rhythm patients? A retrospective comparison to adenosine SPECT
AUTHORS:
Gurunanthan Palani, Aarthee S. Karthikeyan, Jacobsen Gordon, Karthik Ananthasubramaniam
KEYWORDS:
Regadenoson; Single Photon Emission Computed Tomography; Left Bundle Branch Block; Ventricular Paced Rhythm; Adenosine; False Positive SPECT
JOURNAL NAME:
World Journal of Cardiovascular Diseases,
Vol.3 No.2,
April
28,
2013
ABSTRACT: Purpose:
Regadenoson (REG) is currently becoming the stress
agent of choice in patients undergoing pharmacologic single photon emission
computed tomography (SPECT). However, in patients with left bundle branch block
(LBBB) and ventricular paced rhythm (VPR), hesitation exists amongst clinicians
to use REG-SPECT due to the concern that the increased heart rate could cause
false positive SPECT results. We sought to evaluate the comparability of A-SPECT
and REG-SPECT in patients with LBBB and VPR. Methods: Retrospective study of 30
patients who served as their own controls. All 30 patients who underwent REG-SPECT
(Grp 1) were compared to their prior A-SPECT (Grp 2) done within two years prior
to REG-SPECT. Heart rate (HR) and blood pressure (BP) parameters, ECG, stress perfusion
and gated variables, SPECT ischemia, and side-effects were evaluated. Statistical
significance was set at P could be found between the two groups among SPECT
parameters. Muscle pain was significantly higher in REG (10.0% vs. 0.0%, P = 0.083)
and so was the use of aminophylline (16.7% vs. 0.0%, P = 0.025) to relieve the side-effect. Conclusion: REG-SPECT
can be administered in patients with LBBB and VPR patients based on favorable and
comparable hemodynamic responses and arrhythmia occurrences to A-SPECT. REG-SPECT
can also be used for adequate interpretation of presence or absence of SPECT ischemia
particularly in the LAD territory without any concern for false positive perfusion
defects.