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Prognostic impact of coronary microvascular dysfunction in patients with atrial fibrillation
Ayman A Mohammed1, Siqi Li2, Hengbin Zhang2
1Department of Cardiology, Shanghai Tenth People's Hospital, Tongji University School of Medicine, Shanghai, China; Department of Internal Medicine, Faculty of Medicine and Health Science, Taiz University, Yemen.
Insights
Coronary microvascular dysfunction (CMD), indicated by elevated coronary angiography-derived index of microcirculatory resistance (caIMR), predicts major adverse events in atrial fibrillation (AF) patients. This finding highlights microvascular function as a key prognostic marker and therapeutic target in AF.
Area of Science:
- Cardiology
- Vascular Biology
- Arrhythmia Research
Background:
- Coronary microvascular dysfunction (CMD) is prevalent in atrial fibrillation (AF) but its prognostic value is unclear.
- Assessing CMD using a novel coronary angiography-derived index of microcirculatory resistance (caIMR) offers new insights.
Purpose of the Study:
- To investigate the prognostic significance of caIMR for major adverse cardiovascular events (MACE) in patients with AF.
- To determine if caIMR can serve as an independent predictor of outcomes in this population.
Main Methods:
- Inclusion of 463 AF patients without obstructive coronary artery disease undergoing coronary angiography.
- Prospective evaluation of caIMR and determination of its optimal cutoff for MACE prediction via ROC analysis.
- Follow-up for a median of 33 months to assess MACE endpoints.
Main Results:
- 111 (23.97%) patients experienced MACE.
- An elevated caIMR (cutoff 39.28) was significantly higher in MACE patients and independently predicted adverse events (HR: 4.029).
- Higher MACE risk was observed in patients with elevated caIMR, non-paroxysmal AF, and without prior catheter ablation.
Conclusions:
- Elevated caIMR is common in AF patients and holds significant independent prognostic value.
- Microvascular function assessment via caIMR is a feasible approach for early prevention and therapeutic targeting in AF.
- caIMR provides crucial prognostic information beyond traditional risk factors in AF.
Background:
Coronary microvascular dysfunction (CMD) is frequently observed in atrial fibrillation (AF), the most commonly sustained arrhythmia. Nevertheless, an in-depth prognostic significance of CMD in AF is lacking. We aimed to provide insight into the predictive impact of CMD assessed by a novel non-invasive coronary angiography-derived index of microcirculatory resistance (caIMR) for major adverse events (MACE) in AF patients.
Method:
This study included patients with AF who underwent invasive coronary angiography due to suspected cardiac ischemia and did not exhibit obstructive epicardial coronary artery disease (≤50 % stenosis). The caIMR was prospectively evaluated, and the optimal cutoff value for predicting MACE was determined through ROC analysis.
Result:
A total of 463 patients with AF were enrolled. During a median of 33 months of follow-up, 111 (23.97 %) patients had MACE endpoints. The best caIMR cutoff value was 39.28. In patients with MACE, both the mean caIMR and the prevalence of elevated caIMR (caIMR>39.28) were significantly higher compared to those without MACE. An elevated caIMR was linked to a higher risk of MACE (log-rank P < 0.001) and emerged as an independent predictor of clinical outcomes (HR: 4.029; 95 % CI: 2.529-6.418; P < 0.001). In addition, the risk of MACE was higher in high caIMR patients with non-paroxysmal AF (log-rank P < 0.001) and no catheter ablation (log-rank P < 0.001).
Conclusion:
Elevated caIMR is common and showed a vital independent prognostic significance in AF patients. In addition to well-known risk factors, assessment of microvascular function can be a feasible approach for early prevention and a therapeutic target in AF patients.
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