OR08-2
Intravenous vs Intracoronary Adenosine for the Determination of Coronary Flow Reserve and Index of Microcirculatory Resistance
Presenter
Jay J Widmer, M.D., Ph.D., FSCAI, Baylor Scott & White Medical Center – Temple, Belton, TX
Fazal Dalal, D.O.1, Jose Emilio Exaire, M.D., FSCAI2, Timothy A. Mixon, M.D., FSCAI2 and Jay J Widmer, M.D., Ph.D., FSCAI3, (1)Baylor Scott and White - Temple, Temple, TX, (2)Baylor Scott & White Clinic - Temple, Temple, TX, (3)Baylor Scott & White Medical Center – Temple, Belton, TX
Keywords: Acute Coronary Syndromes (ACS), Coronary, Imaging & Physiology and Stable Ischemic Heart Disease (SIHD)
Background
-
Coronary Flow Reserve (CFR) and Index of Microcirculatory Resistance (IMR) obtained via coronary bolus thermodilution assess microvascular function. Previous studies demonstrate comparable results assessing ischemia by fractional flow reserve using intravenous (IV) or intracoronary (IC) adenosine. It is unknown if there is similarity when assessing CFR and IMR using coronary thermodilution.
Methods
-
We reviewed coronary reactivity testing (CRT) data and baseline demographics in a cohort of patients who underwent CRT for non-obstructive CAD. We evaluated CFR and IMR in patients whereby maximal hyperemia was obtained by both IC and IV means using linear regression and Bland-Altman analysis.
We assessed 25 patients with a median age of 61 (52,67) and 87% female. Average CFR with IC adenosine was 3.4+1.6 and 3.0+1.3 with IV adenosine with an R2 value of 0.15 (p=0.06). Average IMR with IC adenosine was 31.3+21.1 and 29.5+18.8 with IV adenosine with an R2 value of 0.45 (p=0.0005). Bland Altman analysis showed reasonable agreement between IV and IC adenosine for CFR (Figure 1A) and IMR (Figure 1B) with slightly higher values using IC adenosine.
Conclusions
-
CFR and IMR values obtained with IC adenosine are similar to those with IV adenosine. This presents a potential alternative to IV adenosine for bolus thermodilution CRT testing. 