Differences in coronary microcirculation measurements during regadenoson vs. adenosine - induced hyperemia

Area of Science:

• Cardiology
• Cardiovascular Research
• Medical Diagnostics

Background:

• Limited data exists on comparing microcirculation assessment outcomes between regadenoson and adenosine.
• Understanding these differences is crucial for accurate diagnostic interpretations.

Purpose of the Study:

• To compare coronary flow reserve (CFR) and index of microcirculatory resistance (IMR) assessments using adenosine versus regadenoson.
• To identify predictors for variations in CFR and IMR values based on the hyperemia agent used.

Main Methods:

• 44 patients underwent dual assessments of FFR, CFR, and IMR in either the circumflex or LAD artery.
• Measurements were taken sequentially, first with adenosine infusion, followed by regadenoson administration 10 minutes later.

Main Results:

• No statistically significant differences were observed in averaged FFR, CFR, or IMR values between adenosine and regadenoson.
• Prior angioplasty/stenting, anticoagulant use, and history of stroke/TIA predicted greater CFR differences.
• History of stroke/TIA and NYHA class II/III predicted greater IMR differences.

Conclusions:

• Regadenoson demonstrates feasibility as an alternative to adenosine for coronary microcirculation assessment due to similar outcomes.
• Specific patient characteristics influence the magnitude of differences in IMR, CFR, and FFR values depending on the hyperemia agent.