Cardiac Geometry and Function in Patients with Reflex Syncope.
Coseriu, Giorgia, Schiop-Tentea, Patricia, Apetrei, Csilla-Andrea et al. · Journal of clinical medicine · 2024 · DOI
Quick Summary
This review examines how the size and function of the heart relate to fainting episodes in people with reflex syncope. Researchers found that people with smaller hearts and very forceful heartbeats are more prone to fainting, and this pattern is also seen in some people with chronic fatigue syndrome. Understanding these heart differences may help doctors predict who will faint again and choose better treatments.
Why It Matters
This study is relevant to ME/CFS research because it identifies a specific cardiac phenotype (small heart with high contractility) that appears in both reflex syncope and chronic fatigue syndrome patients. Understanding these overlapping cardiac abnormalities may clarify why ME/CFS patients often experience orthostatic intolerance and syncope, and could support development of cardiac-targeted treatments. The proposed predictive parameters could improve risk stratification in ME/CFS populations prone to syncope.
Observed Findings
Small left ventricular and atrial volumes are associated with increased syncope susceptibility.
Normal or hypercontractile myocardium is present in syncope-prone patients despite reduced chamber size.
Chronic fatigue syndrome and reflex syncope share similar cardiac geometry patterns.
Cardiac chamber geometry and electrical activation parameters show predictive value for syncope recurrence.
Cardiac structural parameters may inform choice of treatment strategy (medications, pacing, or ablation).
Inferred Conclusions
A specific cardiac phenotype (small, hypercontractile heart) predisposes to reflex syncope in susceptible patients.
Common pathophysiologic pathways may link reflex syncope and chronic fatigue syndrome through shared cardiac structural abnormalities.
Cardiac geometry and electrical parameters could be incorporated into predictive models to identify high-risk syncope recurrence.
Cardiac phenotyping may guide individualized treatment selection in syncope management.
Remaining Questions
Why do some patients with small, hypercontractile hearts develop syncope while others do not?
What This Study Does Not Prove
This review does not establish causation—it identifies associations between cardiac geometry and syncope recurrence. It does not prove that all ME/CFS patients have these cardiac changes, nor does it establish whether small heart size causes syncope or vice versa. The study cannot determine which treatment strategies are most effective, only that geometry parameters may have predictive utility.
About the PEM badge: “PEM required” means post-exertional malaise was an explicit required diagnostic criterion for participant inclusion in this study — not that PEM was studied, observed, or discussed. Studies using criteria that do not require PEM (e.g. Fukuda, Oxford) are tagged “PEM not required”. How the atlas works →