44
Special Populations
6.1.2. Ischemia With Nonobstructive Coronary Arteries
COR LOE
Recommendation
2a B-R 1. In symptomatic patients with nonobstructive CAD, a strategy
of stratified medical therapy* guided by invasive coronary
physiologic testing can be useful for improving angina severity
and QOL.
* See recommendation-specific supportive text for details.
Table 15. Clinical Criteria for Suspecting Microvascular
Angina*
Criteria Evidence Diagnostic Parameters
1 Symptoms of myocardial
ischemia
Effort or rest angina; exertional dyspnea
2 Absence of obstructive CAD
(<50% diameter reduction or
FFR >0.80)
Coronary CTA; invasive coronary
angiography
3 Objective evidence of
myocardial ischemia
Ischemic changes on ECG during an
episode of chest pain; stress-induced chest
pain and/or ischemic changes on ECG
in the presence or absence of transient/
reversible abnormal myocardial perfusion
and/or wall motion abnormality
4 Evidence of impaired coronary
microvascular function
Impaired coronary flow reserve (cut-off
value depending on methodolog y between
≤0.20 and ≤0.25); coronary microvascular
spasm, defined as reproduction of
symptoms, ischemic shifts on ECG but
no epicardial spasm during acetylcholine
testing ; abnormal coronary microvascular
resistance indices (eg, IMR >25); coronary
slow flow phenomenon, defined as TIMI
frame count >25
* Definitive microvascular angina is only diagnosed if all 4 criteria are present for a diagnosis
of microvascular angina.
Suspected microvascular angina is diagnosed if symptoms of ischemia are present (criteria 1)
with no obstructive CAD (criteria 2) but only (a) objective evidence of myocardial ischemia
(criteria 3) or (b) evidence of impaired coronary microvascular function (criteria 4) alone.
Adapted with permission from Ong P, et al. Int J Cardiol. 2018;250:16-20. Copyright 2018,
with permission from Elsevier.
