Simplified Assessment of the Index of Microvascular Resistance.

Monika Kodeboina,Frederik Van Durme,Bernard De Bruyne,Emanuele Gallinoro,Takuya Mizukami,Niya Mileva,Marc Vanderheyden,Carlos Collet,Alessandro Candreva,Jeroen Sonck,Daniel Munhoz,Eric Wyffels,Emanuele Barbato,Alex Heyse,Jozef Bartunek,Sakura Nagumo,Stefano Rigattieri

doi:10.1155/2021/9971874

Abstract

Background To validate a simplified invasive method for the calculation of the index of microvascular resistance (IMR). Methods This is a prospective, single-center study of patients with chronic coronary syndromes presenting with nonobstructive coronary artery disease. IMR was obtained using both intravenous (IV) adenosine and intracoronary (IC) papaverine. Each IMR measurement was obtained in duplicate. The primary objective was the agreement between IMR acquired using adenosine and papaverine. Secondary objectives include reproducibility of IMR and time required for the IMR measurement. Results One hundred and sixteen IMR measurements were performed in 29 patients. The mean age was 68.8 ± 7.24 years, and 27.6% was diabetics. IMR values were similar between papaverine and adenosine (17.7 ± 7.26 and 20.1 ± 8.6, p=0.25; Passing-Bablok coefficient A 0.58, 95% CI −2.42 to 3.53; coefficient B 0.90, 95% CI −0.74 to 1.07). The reproducibility of IMR was excellent with both adenosine and papaverine (ICC 0.78, 95% CI 0.63 to 0.88 and ICC 0.93, 95% CI 0.87 to 0.97). The time needed for microvascular assessment was significantly shortened by the use of IC papaverine (3.23 (2.84, 3.78) mins vs. 5.48 (4.94, 7.09) mins, p < 0.0001). Conclusion IMR can be reliably measured using IC papaverine with similar results compared to intravenous infusion of adenosine with increased reproducibility and reduced procedural time. This approach simplifies the invasive assessment of the coronary microcirculation in the catheterization laboratory.

Highlights

Coronary microvascular dysfunction (CMD) remains an illdefined condition
Guidelines recommend the invasive assessment of the coronary microvascular resistance in patients with angina and nonobstructive coronary artery disease [1]
Patients underwent microvascular evaluation with bolus thermodilution in rest and hyperemia using IV adenosine and IC papaverine, both acquired in duplicated measurements. e study protocol was approved by the institutional ethics committee (Institutional Ethics Committee 2020/013)

Summary

Introduction

Guidelines recommend the invasive assessment of the coronary microvascular resistance in patients with angina and nonobstructive coronary artery disease [1]. IMR has emerged as an invasive reproducible method for assessing the coronary microcirculation [13]. Intravenous (IV) adenosine has been the favored hyperemic agent. Papaverine is an alternative hyperemic agent suitable for intracoronary administration that induces a stable hyperemic state sufficient to evaluate hyperemic mean transit times and IMR [16]. IMR can be reliably measured using IC papaverine with similar results compared to intravenous infusion of adenosine with increased reproducibility and reduced procedural time. Is approach simplifies the invasive assessment of the coronary microcirculation in the catheterization laboratory IMR can be reliably measured using IC papaverine with similar results compared to intravenous infusion of adenosine with increased reproducibility and reduced procedural time. is approach simplifies the invasive assessment of the coronary microcirculation in the catheterization laboratory

Methods

Results

Conclusion