Aim: Although the association between left ventricular dilation and mitral annulus dilation is well understood, the potential variation in the size of the mitral annulus during dilation of the left atrium is currently unknown. In order to investigate the link between the two variables, we used multidetector computed tomography (MDCT) and looked at patients who had a dilated left atrium, assessing if the mitral valve also dilates. Materials and Methods: The study included 107 patients with paroxysmal and persistent atrial fibrillation, in whom catheter ablation was performed using pulmonary vein isolation ± atrial substrate modification. Eighty patients were male (74.8%), with a mean age of 55.8 years (±9.87 with a minimum age of 26 years and a maximum age of 79 years), of which 57.1% had paroxysmal AF and the rest had persistent fibrillation. All the patients underwent multiple-detector CT (MDCT) with contrast medium before the ablation. CT images were integrated into the three-dimensional mapping system CARTO 3, after which the diameters of the mitral annulus, area, and circumference were measured. Left atrial size was evaluated by measuring the diameters, area, and volume. Results: The left atrial area was 247 ± 65.7 cm2 and the left atrial volume was 139 ± 56.3 mL. The transverse mitral annulus (MA) was 29.9 ± 5.3 mm and the longitudinal diameter was 41.9 ± 7.6 mm. The MA circumference and area were 15.0 ± 3.5 cm and 14.2 ± 4.6 cm², respectively. The following statistically significant correlation was identified between the dimensions of the mitral annulus and the diameters of the left atrium: the transverse mitral annulus correlates with the antero-posterior (AP) LA diameter (R = 0.594, p < 0.01) and the longitudinal MA diameter correlates with the latero-lateral (LL) LA diameter (R = 0.576, p < 0.01). Furthermore, the MA area correlates with the LA volume (R = 0.639, p < 0.001). Conclusions: The volume of the left atrium correlates with the area of the mitral annulus. In patients with paroxysmal and persistent AF, an increase in left atrial dimensions is further associated with an increase in mitral valve dimensions.

Background/Objectives: Minimalist footwear has been proposed as a passive means of reducing knee loading, but its effects during walking in healthy adults, the population relevant to primary prevention of knee osteoarthritis (KOA), have not previously been synthesized. Methods: Following PRISMA 2020 (PROSPERO CRD420261396693), four databases and ClinicalTrials.gov were searched to September 2026 without date restriction. Primary outcomes were peak knee adduction moment (KAM), KAM impulse, peak knee flexion moment (KFM), and patellofemoral contact force; secondary outcomes were vertical loading rate, stride length, cadence, foot strike angle, and foot progression angle as a registered post hoc amendment. Risk of bias was assessed in duplicate with the Cochrane RoB 2 tool for crossover trials; synthesis was narrative; certainty was rated with GRADE. Results: Six publications met the criteria, but they derive from only four independent cohorts and 100 unique participants: three of the six report the same cohort of 40, a shared structure disclosed in none of them. Two of the four primary outcomes were reported by a single study in one cohort of 16, which found no difference between minimalist and conventional footwear in either peak KAM or peak KFM; KAM impulse and patellofemoral contact force were not reported by any study. Vertical loading rate, spatiotemporal parameters, and foot progression angle were discordant or non-comparable between cohorts. The meta-analysis was precluded by overlapping samples, absent discrete data and non-comparable outcome definitions; certainty was very low for every outcome. Conclusions: The evidence is smaller and less independent than its publication count suggests, and no recommendation for or against minimalist footwear in KOA prevention is currently supportable. Whether these loading markers, studied mainly in relation to progression in established osteoarthritis rather than incident disease in healthy joints, are appropriate prevention targets also remains unclear.