The research team, led by Javier Sanmartin and Roberto Elosua of the University of Vic-Central University of Catalonia, followed PRISMA guidelines and prospectively registered their protocol in PROSPERO. They searched PubMed, Scopus, and Web of Science from database inception through September 2023, with an updated search extending to June 2025. From 5,963 initially identified articles, the investigators retained 115 original studies after removing duplicates and screening titles, abstracts, and full texts. Risk of bias was assessed with the Joanna Briggs Institute Critical Appraisal Tool for Cross-Sectional Studies, and pooled estimates were generated using random-effects models with the Freeman-Tukey double arcsine transformation for proportions.

The headline number is 4 percent. Using the International-Seattle criteria, which define T-wave inversion as a negative T-wave of at least 1 millimeter in two contiguous leads, the pooled prevalence among athletes older than 16 years was 4 percent, with a 95 percent confidence interval of 3 to 6 percent. That figure, however, masks enormous variability: individual studies reported prevalences ranging from 0 to 42 percent, and the between-study heterogeneity, quantified by the I-squared statistic, exceeded 80 percent in most meta-analyses. The authors caution that the pooled estimate should be interpreted with this heterogeneity firmly in mind.

Location on the electrocardiogram matters enormously. Inversions were most common in the anterior leads V2 through V4, at roughly 3 percent, while inferior leads showed about 1 percent and lateral leads essentially 0 percent. This anatomical gradient carries clinical weight because lateral T-wave inversion is the pattern most frequently linked to confirmed structural heart disease. In the studies that evaluated cardiomyopathies among athletes with T-wave inversion, the most commonly identified conditions were hypertrophic cardiomyopathy, arrhythmogenic ventricular cardiomyopathy, and dilated cardiomyopathy, and lateral-lead inversions were disproportionately represented among those diagnosed.

Ethnicity emerged as a major modifier of prevalence. Black athletes showed an overall T-wave inversion rate of 13 percent, compared with 3 percent in Caucasian athletes, a difference consistent with known genetic, endocrine, and hemodynamic factors, including greater myocardial wall thickness and left ventricular mass. Notably, recent work cited in the review found that geographical origin within Africa also matters, with repolarisation abnormalities significantly more common among West African and Middle African athletes than among those from East or North Africa. Sex differences were smaller but present: women showed a slightly higher overall prevalence than men, 7 percent versus 5 percent, driven by anterior and inferior leads.

Perhaps the most striking comparative finding is that T-wave inversion is roughly 49 percent more common in athletes than in non-athletes. Across 14 studies that included control populations, the pooled prevalence ratio was 1.49, with a confidence interval of 1.13 to 1.97. The effect was strongest in the inferior leads, where the ratio reached 1.70. This supports the idea that intense training itself, through ventricular remodeling and autonomic changes, produces repolarisation patterns that would be considered abnormal in a sedentary person but are often physiological in an athlete.

The mechanisms behind these training-related inversions are diverse. The authors describe ventricular remodeling effects, including a high papillary muscle to left ventricular mass ratio and lateral displacement of the cardiac apex, which can explain anterior inversions. Structural variants such as left ventricular false tendons have also been implicated. Enhanced vagal tone in trained athletes activates acetylcholine-controlled potassium channels, reducing the action potential gradient between the epicardium and endocardium and altering the repolarisation vector. Myocardial ischemia, by contrast, can invert the repolarisation gradient in a pathological direction, which is one reason the finding cannot simply be dismissed.

Age adds another layer of nuance. In athletes aged 16 or younger, a juvenile T-wave inversion pattern in leads V1 through V3 is considered a normal variant, reflecting right ventricular dominance in early adolescence, and it generally regresses after age 16. The meta-analysis found this juvenile pattern in about 6 percent of young athletes. Interestingly, meta-regression identified age as the only variable that partially explained the heterogeneity between studies, with older athletes showing higher prevalence, a relationship the authors attribute to cumulative lifetime training volume.

On the critical prognostic question, the picture is murkier. Among 34 studies that assessed structural cardiomyopathies in athletes with T-wave inversion, most reported disease prevalence below 1 percent, though nine studies found rates between 1 and 10 percent and six exceeded 10 percent, likely reflecting deeper inversions, lateral predominance, referral-center recruitment, and more sensitive imaging such as cardiac magnetic resonance. Follow-up data were similarly heterogeneous: annual incidence rates of newly diagnosed cardiomyopathy ranged from 0 to 54.9 cases per 1,000 athletes, and major cardiovascular events ranged from 0 to 83.33 per 1,000 athlete-years. The authors attribute this wide spread to small samples, short follow-up, and selection biases, leaving the true event risk statistically uncertain.

The clinical message is a careful balance. T-wave inversion in athletes is more common than in the general population, most often involves the anterior leads, and frequently reflects benign exercise-induced remodeling, particularly in Black athletes and in younger age groups. Yet because it can also herald hypertrophic, arrhythmogenic, or dilated cardiomyopathy, especially when it appears in lateral leads or is accompanied by ST-segment depression, a thorough evaluation remains essential. The authors call for international, standardized, prospective studies with adequate sample sizes, uniform diagnostic protocols incorporating echocardiography, exercise testing, Holter monitoring, and cardiac magnetic resonance, and long-term follow-up to finally pin down which athletes with inverted T-waves truly need to worry.

Subject of Research: Prevalence and prognostic significance of T-wave inversions on electrocardiograms in athletes

Article Title: Frequency and Prognostic Significance of T-wave Inversions in Athletes: A Systematic Review and Meta-analysis

Article References: Sanmartin, J., Cartanya-Bonvehi, J., Valenzuela, H., Carballeira, L., Montserrat, S., Baranchuk, A., & Elosua, R. (2026). Frequency and Prognostic Significance of T-wave Inversions in Athletes: A Systematic Review and Meta-analysis. Sports Medicine – Open, 12(1), Article 147. https://doi.org/10.1186/s40798-026-01115-9

Image Credits: AI Generated

DOI: 10.1186/s40798-026-01115-9

Keywords: T-wave inversion, athletes, electrocardiogram, sudden cardiac death, cardiomyopathy, sports cardiology, meta-analysis, athlete's heart, ECG screening, ventricular remodeling, hypertrophic cardiomyopathy, prevalence