Prognostic effect of invasively diagnosed coronary microvascular dysfunction: A systematic review and META-analysis

Area of Science:

• Cardiology
• Vascular Biology
• Clinical Research

Background:

• Obstructive coronary artery disease is linked to major adverse cardiovascular events (MACE).
• Emerging evidence highlights the critical role of coronary microvascular dysfunction (CMD) in cardiovascular outcomes.
• CMD assessment is vital for predicting prognosis.

Purpose of the Study:

• To conduct a meta-analysis summarizing the prognostic impact of CMD on cardiovascular outcomes and mortality.
• To evaluate the association between invasive indices of CMD (coronary flow reserve [CFR] and index of microcirculatory resistance [IMR]) and patient prognosis.

Main Methods:

• Systematic literature search of MEDLINE/PubMed and Scopus databases.
• Meta-analysis of 31 studies (13,016 patients) comparing prognosis in CMD versus non-CMD.
• Calculation of pooled risk ratios (RR) for MACE and mortality using invasive CFR and IMR data.

Main Results:

• CMD was associated with a 2.55-fold increased risk of MACE.
• Significant increases in all-cause mortality (1.88-fold), cardiovascular mortality (2.76-fold), myocardial infarction (2.18-fold), and stroke (1.85-fold) were observed.
• Worse outcomes were noted in acute coronary syndrome patients and those with structural CMD.

Conclusions:

• Invasively diagnosed CMD significantly elevates MACE risk and cardiovascular mortality.
• This underscores the necessity of assessing both macro- and microcirculation for comprehensive cardiovascular evaluation.
• CMD is an independent predictor of adverse cardiovascular events.