TY - JOUR
T1 - Reference values for intracoronary Doppler flow velocity-derived hyperaemic microvascular resistance index
AU - Feenstra, Rutger G. T.
AU - Seitz, Andreas
AU - Boerhout, Coen K. M.
AU - de Winter, Robbert J.
AU - Ong, Peter
AU - Beijk, Marcel A. M.
AU - Piek, Jan J.
AU - Sechtem, Udo
AU - van de Hoef, Tim P.
N1 - Funding Information: None. Publisher Copyright: © 2022 The Author(s)
PY - 2023/1/15
Y1 - 2023/1/15
N2 - Background: Invasive assessments of microvascular function are rapidly becoming an integral part of physiological assessment in chronic coronary syndromes. Objective: We aimed to establish a reference range for Doppler flow velocity-derived hyperaemic microvascular resistance index (HMR) in a cohort of angina with no significant epicardial coronary obstruction (ANOCA) patients with no structural pathophysiological alterations in the coronary circulation. Methods: The reference population consisted of ANOCA patients undergoing invasive coronary vasomotor function assessment who had a coronary flow reserve (CFR) >2.5, and had either (1) tested negatively for spasm provocation (n = 12) or (2) tested positively with only angina at rest (n = 29). A reference range for HMR was established using a non-parametric method and correlations with clinical characteristics were determined using a spearman rank correlation analysis. Results: In 41 patients median HMR amounted to 1.6 mmHg/cm/s [Q1, Q3: 1.3, 2.2 mmHg/cm/s]. The reference range for HMR that is applicable to 95% of the population was 0.8 mmHg/cm/s (90% CI: 0.8–1.0 mmHg/cm/s) to 2.7 mmHg/cm/s (90% CI: 2.6–2.7 mmHg/cm/s). No significant correlations were found between HMR and clinical characteristics. Conclusion: In this reference population undergoing invasive coronary vasomotor function testing, the 90% confidence interval of the HMR upper limit of normal ranges from 2.6 to 2.7 mmHg/cm/s. A > 2.5 mmHg/cm/s HMR threshold can be used to identify abnormal microvascular resistance in daily clinical practice.
AB - Background: Invasive assessments of microvascular function are rapidly becoming an integral part of physiological assessment in chronic coronary syndromes. Objective: We aimed to establish a reference range for Doppler flow velocity-derived hyperaemic microvascular resistance index (HMR) in a cohort of angina with no significant epicardial coronary obstruction (ANOCA) patients with no structural pathophysiological alterations in the coronary circulation. Methods: The reference population consisted of ANOCA patients undergoing invasive coronary vasomotor function assessment who had a coronary flow reserve (CFR) >2.5, and had either (1) tested negatively for spasm provocation (n = 12) or (2) tested positively with only angina at rest (n = 29). A reference range for HMR was established using a non-parametric method and correlations with clinical characteristics were determined using a spearman rank correlation analysis. Results: In 41 patients median HMR amounted to 1.6 mmHg/cm/s [Q1, Q3: 1.3, 2.2 mmHg/cm/s]. The reference range for HMR that is applicable to 95% of the population was 0.8 mmHg/cm/s (90% CI: 0.8–1.0 mmHg/cm/s) to 2.7 mmHg/cm/s (90% CI: 2.6–2.7 mmHg/cm/s). No significant correlations were found between HMR and clinical characteristics. Conclusion: In this reference population undergoing invasive coronary vasomotor function testing, the 90% confidence interval of the HMR upper limit of normal ranges from 2.6 to 2.7 mmHg/cm/s. A > 2.5 mmHg/cm/s HMR threshold can be used to identify abnormal microvascular resistance in daily clinical practice.
KW - Angina
KW - Coronary vasomotor dysfunction
KW - Hyperaemic microvascular resistance
KW - Non-obstructive coronary artery disease
KW - Reference value
UR - http://www.scopus.com/inward/record.url?scp=85139730734&partnerID=8YFLogxK
U2 - https://doi.org/10.1016/j.ijcard.2022.09.054
DO - https://doi.org/10.1016/j.ijcard.2022.09.054
M3 - Article
C2 - 36174827
SN - 0167-5273
VL - 371
SP - 16
EP - 20
JO - International Journal of Cardiology
JF - International Journal of Cardiology
ER -