QRS fragmentation on the 12-lead electrocardiogram and its association to physiological cardiac adaptation in elite cyclists

Goodman, M, Malhotra, A, Cooper, R ORCID: 0000-0001-7482-828X, Robinson, S, Maxwell, J ORCID: 0000-0001-7894-7075, Place, F, George, K ORCID: 0000-0002-5119-6651, Knights, M, Jones, N and Oxborough, D ORCID: 0000-0002-1334-3286 (2026) QRS fragmentation on the 12-lead electrocardiogram and its association to physiological cardiac adaptation in elite cyclists. International Journal of Cardiology, 447. ISSN 0167-5273

Preview

Text QRS fragmentation on the 12-lead electrocardiogram and its association to physiological cardiac adaptation in elite cyclists.pdf - Published Version Available under License Creative Commons Attribution. Download (866kB) | Preview

Abstract

Background
The relationship between electrocardiographic based QRS fragmentation (fQRS) and physiological cardiac adaptation is not fully understood. We aimed to determine the prevalence of fQRS in elite male and female cyclists, and relationship between fQRS and cardiac structure and function.

Methods
181 Elite international cyclists underwent their national cycling team's pre-participation cardiac screening. This included a resting 12‑lead electrocardiogram and transthoracic echocardiogram. Fragmented QRS was defined as an additional notch >1 mm deep from the peak of the wave within the QRS complex in any lead. We excluded RSR’ or RSR'S′ patterns in V1–2 to differentiate from bundle branch block.

Results
Fragmented QRS was observed in 73 (41 %) of the cyclists. The most common lead was V1, followed by lead III, aVL and aVF. Of those cyclists with fQRS it was observed in just one lead in 38 cyclists (52 %), two leads in 22 cyclists (30 %) and ≥ three leads in 13 cyclists (18 %). Cyclists with fQRS demonstrated greater left ventricular (LV) diastolic diameter index (p = 0.008), mean wall thickness (p < 0.001), LV mass index (p = 0.001), proximal right ventricular (RV) outflow diameter (RVOTPLAX) index (p = 0.040), distal RVOT2 index (p < 0.001), RV systolic area index (p = 0.005), and RV:LV ratio (p = 0.008). In addition, cyclists with fQRS had significantly lower RV fractional area change (p = 0.002).

Conclusion
Fragmented QRS in athletes is associated with indices of physiological LV and RV adaptation. In isolation, fQRS may not raise concern or initiate any further onward investigations.

Item Type:	Article
Uncontrolled Keywords:	Athlete's heart; Cardiac remodelling; QRS fragmentation; 32 Biomedical and Clinical Sciences; 3201 Cardiovascular Medicine and Haematology; Cardiovascular; Heart Disease; Cardiovascular; 1102 Cardiorespiratory Medicine and Haematology; 1117 Public Health and Health Services; Cardiovascular System & Hematology; 3201 Cardiovascular medicine and haematology
Subjects:	R Medicine > RC Internal medicine > RC1200 Sports Medicine
Divisions:	Sport and Exercise Sciences
Publisher:	Elsevier BV
Date of acceptance:	31 December 2025
Date of first compliant Open Access:	16 January 2026
Date Deposited:	16 Jan 2026 16:14
Last Modified:	16 Jan 2026 16:14
DOI or ID number:	10.1016/j.ijcard.2025.134149
URI:	https://researchonline.ljmu.ac.uk/id/eprint/27931

View Item