Circumferential clues: strain patterns and arrhythmia risk in pulmonary regurgitation

Slim et al.'s paper provided an insight into the differences between repaired tetralogy of Fallot and isolated pulmonary regurgitation in their strain. Repaired tetralogy of Fallot had higher right ventricular circumferential strain, while isolated pulmonary regurgitation relied on longitudinal strain more. This allowed the authors to infer that repaired tetralogy of Fallot can withstand more chronic regurgitation before valve replacement is necessary. We highlighted new findings relevant to this paper. Arrhythmia in repaired tetralogy of Fallot is associated with a reduced global circumferential strain of the right ventricle. Specifically, a value of below -14% was associated with a 6.3 times increase in the risk for an arrhythmic event. We believe this would be beneficial for patients when considered for valve replacements, suggesting modification of current valve replacement guidelines to include strain thresholds alongside current volumetric thresholds. However, the data for isolated pulmonary regurgitation remains scarce. Further investigation is needed to provide clearer timelines for valve replacement. We emphasised the importance of exploring the underlying architecture of repaired tetralogy of Fallot patients' hearts and why they could generate more global circumferential strain. We acknowledged the broader effect of this paper and its specific benefit in our country, Egypt. This paper provided insights useful for broader global health impact, especially in low-income countries.