Uğur Canpolat1, Kudret Aytemir2, Tuncay Hazirolan3, Necla Özer2, Ali Oto2. 1. Department of Cardiology, Hacettepe University Faculty of Medicine, Ankara, Turkey. Electronic address: dru_canpolat@yahoo.com. 2. Department of Cardiology, Hacettepe University Faculty of Medicine, Ankara, Turkey. 3. Department of Radiology, Hacettepe University Faculty of Medicine, Ankara, Turkey.
Abstract
BACKGROUND: Left atrial (LA) fibrosis is known as the hallmark for arrhythmogenic substrate in atrial fibrillation (AF). Quantification of LA fibrosis by using delayed-enhanced magnetic resonance imaging (DE-MRI) in AF patients is a pioneering noninvasive technique. Vitamin D (vitD) negatively regulates the renin-angiotensin system, binds to vitD receptors on cardiac myocytes, and has antioxidant properties that may ameliorate the inflammation and proarrhythmic substrate formation. However, its role in LA fibrosis is unclear. We aimed to investigate the association of serum 25(OH)D level with the extent of LA fibrosis by using DE-MRI and also predictors for AF recurrence after cryoablation was assessed in patients with paroxysmal AF. METHODS: A total of 48 patients with lone paroxysmal AF (41.7% female; age: 48.5±8.4 years) who underwent DE-MRI at 1.5T and initial cryoballoon-based catheter ablation along with 48 healthy control subjects were enrolled. Fibrosis degree was categorized according to Utah class defined in the DECAAF study. RESULTS: Serum 25(OH)D levels were significantly lower in AF group compared to control group (25.8±7.6ng/ml vs. 31.0±9.5ng/ml, p=0.004). Serum 25(OH)D levels were associated with moderate-severe LA fibrosis independent of other measures (OR: 0.72, 95% CI: 0.54-0.97, p=0.028). At a mean 16.5±2.6 months follow-up, late recurrence was observed in 10 (20.8%) patients. In multivariable Cox regression analysis, LA volume index (HR: 1.42, 95% CI: 1.01-2.01, p=0.045) and the extent of LA fibrosis (HR: 1.14, 95% CI: 1.01-1.28, p=0.034) were found as independently associated with late AF recurrence during follow-up. CONCLUSION: Lower levels of serum 25(OH)D are significantly associated with more extensive LA fibrosis in patients with lone paroxysmal AF and may be implicated in the pathophysiology of AF recurrence after cryoablation. Further large-scale studies are needed to elucidate the exact role of vitD deficiency and replacement on LA fibrosis.
BACKGROUND: Left atrial (LA) fibrosis is known as the hallmark for arrhythmogenic substrate in atrial fibrillation (AF). Quantification of LA fibrosis by using delayed-enhanced magnetic resonance imaging (DE-MRI) in AFpatients is a pioneering noninvasive technique. Vitamin D (vitD) negatively regulates the renin-angiotensin system, binds to vitD receptors on cardiac myocytes, and has antioxidant properties that may ameliorate the inflammation and proarrhythmic substrate formation. However, its role in LA fibrosis is unclear. We aimed to investigate the association of serum 25(OH)D level with the extent of LA fibrosis by using DE-MRI and also predictors for AF recurrence after cryoablation was assessed in patients with paroxysmal AF. METHODS: A total of 48 patients with lone paroxysmal AF (41.7% female; age: 48.5±8.4 years) who underwent DE-MRI at 1.5T and initial cryoballoon-based catheter ablation along with 48 healthy control subjects were enrolled. Fibrosis degree was categorized according to Utah class defined in the DECAAF study. RESULTS: Serum 25(OH)D levels were significantly lower in AF group compared to control group (25.8±7.6ng/ml vs. 31.0±9.5ng/ml, p=0.004). Serum 25(OH)D levels were associated with moderate-severe LA fibrosis independent of other measures (OR: 0.72, 95% CI: 0.54-0.97, p=0.028). At a mean 16.5±2.6 months follow-up, late recurrence was observed in 10 (20.8%) patients. In multivariable Cox regression analysis, LA volume index (HR: 1.42, 95% CI: 1.01-2.01, p=0.045) and the extent of LA fibrosis (HR: 1.14, 95% CI: 1.01-1.28, p=0.034) were found as independently associated with late AF recurrence during follow-up. CONCLUSION: Lower levels of serum 25(OH)D are significantly associated with more extensive LA fibrosis in patients with lone paroxysmal AF and may be implicated in the pathophysiology of AF recurrence after cryoablation. Further large-scale studies are needed to elucidate the exact role of vitD deficiency and replacement on LA fibrosis.
Authors: Maria Barsan; Anca Monica Brata; Abdulrahman Ismaiel; Dinu Iuliu Dumitrascu; Andrei-Vlad Badulescu; Traian Adrian Duse; Stefana Dascalescu; Stefan Lucian Popa; Simona Grad; Lucian Muresan; Carmen Maria Maerescu; Gabriel Cismaru; Vlad Dumitru Brata Journal: Biomedicines Date: 2022-05-26