Factors for heterogeneous outcomes of angina and myocardial ischemia without obstructive coronary atherosclerosis

Understanding Myocardial Infarction with Non-Obstructive Coronary Arteries (MINOCA): a comprehensive meta-analysis of clinical characteristics, management, and prognosis compared to MI with the Obstructive Coronary Artery (MIOCA)

BACKGROUND

MINOCA (Myocardial Infarction with Non-Obstructive Coronary Arteries) represents a unique subset of acute coronary syndrome, distinct from MIOCA (Myocardial Infarction with Obstructive Coronary Arteries) and a control group. This study systematically compares their prevalence, clinical characteristics, management strategies, and outcomes to improve understanding and treatment approaches.

METHODS

This systematic review and meta-analysis followed PRISMA guidelines across multiple databases up to 2024. STATA 17 was used for statistical analyses, and the Newcastle-Ottawa Scale was employed to assess study quality.

RESULTS

One-hundred and twelve studies, including 5,908,768 patients, were analyzed. The pooled prevalence of MINOCA among patients undergoing coronary angiography was 8.92% (95% CI: 8.90-8.94). MINOCA patients were generally younger, predominantly female, and more likely to present with atypical chest pain and dyspnea compared to MIOCA patients. Laboratory findings showed higher levels of CRP, BNP, and fibrinogen in MINOCA patients, suggesting inflammation and microvascular dysfunction as key mechanisms. In contrast, MIOCA patients had higher rates of diabetes and dyslipidemia, highlighting differences in pathophysiological processes. Medication use differed between the groups, with MINOCA patients more likely to be prescribed anticoagulants and β-blockers. Prognostically, MINOCA patients experienced significantly lower rates of adverse short- and long-term outcomes, including major adverse cardiac events (MACE) and cardiovascular death, compared to MIOCA patients.

CONCLUSIONS

This study demonstrated that patients with MINOCA have a better prognosis compared to those with MIOCA and are at a lower risk of serious cardiac events. Based on the findings of this study, we emphasize that microcirculation and vascular spasm are the main mechanisms involved in MINOCA. Considering these findings, it is suggested that a better management strategy for MINOCA patients can be established by precisely defining diagnostic criteria and focusing on anti-inflammatory treatments and risk factor control.

Prediction of outcome by 82Rb PET/CT in patients with ischemia and nonobstructive coronary arteries

BACKGROUND

The purpose of this study was to assess the prognostic value of cardiac 82Rb positron emission tomography (PET)/computed tomography (CT) imaging in patients with myocardial ischemia of nonobstructive coronary arteries (INOCA).

METHODS

We retrospectively evaluated 311 INOCA patients who underwent rest stress 82Rb PET/CT. Cardiac end points were cardiac death, myocardial infarction, or late coronary revascularization. A parametric survival model was also used to identify how the variables influenced time to event.

RESULTS

During a median follow-up of 37 months (range 6-108), 23 (7%) cardiac events occurred. In patients with events total perfusion defect (TPD) was higher and myocardial flow reserve (MFR) lower compared to those without events (both P < .001). At multivariable Cox analysis, increased TPD (i.e., ≥ 5%) and reduced MFR (i.e., < 2) were predictors of events (both P < .001). At Weibull survival analysis, the highest probability of cardiac events and risk acceleration were observed in patients with both increased TPD and reduced MFR. Annualized event rate was higher in patients with reduced MFR compared to those with preserved MFR (P < .001).

CONCLUSION

In patients with INOCA, the combined evaluation of myocardial perfusion and coronary vascular function by 82Rb PET/CT is able to identify those at higher risk of cardiac events.

[Functional cardiovascular symptoms]

This review provides an update on the diagnosis, differential diagnosis and management of functional cardiovascular symptoms. Typical heart-related symptoms like non-cardiac chest pain and palpitations are frequently complemented by other symptoms like dyspnea, sweating, trembling, dizziness and also further somatic symptoms like pain and fatigue. Functional cardiac symptoms are frequent, with rates of up to 30 % in chest pain units. The differential diagnosis comprises gastrointestinal disorders like gastro-esophageal reflux disease and also mental disorders, particularly panic and other anxiety disorders. Successful management depends on an attitude of realizing and confirming the reality and seriousness of the symptoms despite the absence of a clear structural organic cause. Good cooperation with psychotherapists is helpful for stepped care strategies that start with supportive communication with the patient and biopsychosocial self-help activities, leading, if necessary, to formal psychotherapy.