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Published on: August 17, 2022
The prognostic value of coronary endothelial and microvascular dysfunction in subjects with normal or non-obstructive
Philip Brainin1, Daria Frestad2, Eva Prescott1
1Department of Cardiology, Bispebjerg University Hospital, Copenhagen, Denmark.
Insights
Coronary vascular dysfunction in patients without obstructive coronary artery disease (CAD) significantly increases cardiovascular risk. This systematic review confirms the prognostic value of impaired coronary function, even without significant blockages.
Area of Science:
- Cardiology
- Vascular Biology
- Diagnostic Imaging
Background:
- Coronary vascular dysfunction (CVD) is associated with poor cardiovascular outcomes in patients lacking obstructive coronary artery disease (CAD).
- A comprehensive critical appraisal of existing literature on this topic is currently lacking.
- Understanding the prognostic implications of CVD in this population is crucial for clinical management.
Purpose of the Study:
- To systematically review and meta-analyze the cardiovascular risk associated with endothelial-dependent and non-endothelial-dependent CVD.
- To quantify the risk in patients with normal or non-obstructive CAD (epicardial stenosis <50%).
Main Methods:
- Systematic review and meta-analysis of prospective cohort studies.
- Inclusion criteria: studies reporting CVD at baseline and cardiovascular outcomes at follow-up.
- Data synthesis from 26 studies (52 identified papers) across various patient groups including stable angina, heart failure, and diabetes.
Main Results:
- Endothelial-dependent dysfunction showed a summarized risk ratio (RR) of 2.38 (95% CI 1.74-3.25).
- Non-endothelial-dependent dysfunction assessed by coronary flow velocity reserve (CFVR) by echocardiography had an RR of 4.58 (95% CI 3.58-5.87).
- Coronary flow reserve (CFR) by PET indicated an RR of 2.44 (95% CI 1.80-3.30).
- Risk estimates remained robust across sensitivity analyses and were similar in stable angina and other patient groups.
Conclusions:
- Coronary vascular dysfunction in patients with normal or non-obstructive CAD is a significant predictor of adverse cardiovascular outcomes.
- Multicenter studies and standardized guidelines for assessing CVD are recommended.
- These findings underscore the importance of evaluating coronary function beyond epicardial stenosis.
Aims:
Coronary vascular dysfunction is linked with poor cardiovascular prognosis in patients without obstructive coronary artery disease (CAD) but a critical appraisal of the literature is lacking.
Methods And Results:
We performed a systematic review and meta-analysis to quantify the cardiovascular risk associated with endothelial dependent and non-endothelial dependent coronary vascular dysfunction in patients with normal or non-obstructive CAD (epicardial stenosis <50%). Prospective cohort studies that reported coronary vascular dysfunction at baseline and cardiovascular outcomes at follow-up were included. We identified 52 papers of which 26 were included in the meta-analyses. Study populations included stable angina (n=15), heart failure (n=4), diabetes (n=2), hypertrophic obstructive cardiomyopathy (n=2), chronic kidney disease, aortic stenosis and left atrial enlargement (each n=1): RR estimates were similar in patients with stable angina and other patient groups. For epicardial endothelial dependent dysfunction (six studies, 243 events in 1192 patients) the summarized RR was 2.38 (95% confidence intervals (95% CI) 1.74-3.25), for non-endothelial dependent dysfunction assessed as coronary flow velocity reserve (CFVR) by echocardiography (10 studies, 428 events in 5134 patients) RR was 4.58 (95% CI 3.58-5.87) and for coronary flow reserve (CFR) by PET (10 studies, 538 events in 3687 patients) RR was 2.44 (95% CI 1.80-3.30). However, RR estimates were robust in a series of sensitivity analyses.
Conclusion:
The presence of coronary vascular dysfunction in patients with normal or non-obstructive CAD predicts adverse cardiovascular outcome. Multicentre studies and uniform guidelines for assessing coronary vascular dysfunction are encouraged.
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