TY - JOUR

T1 - Reduction in left atrial and pulmonary vein dimensions after ablation therapy is mediated by scar

AU - Gottlieb, Lisa A

AU - Al Jefairi, Nora

AU - El Hamrani, Dounia

AU - Naulin, Jérôme

AU - Lamy, Jérôme

AU - Kachenoura, Nadjia

AU - Constantin, Marion

AU - Quesson, Bruno

AU - Cochet, Hubert

AU - Coronel, Ruben

AU - Dekker, Lukas R C

N1 - © 2021 The Authors. Published by Elsevier B.V.

PY - 2021/12

Y1 - 2021/12

N2 - BACKGROUND: Ablative pulmonary vein isolation (PVI) decreases pulmonary vein (PV) and left atrial (LA) dimensions in atrial fibrillation (AF) patients. These changes are attributed to reverse structural remodeling following sinus rhythm restoration but evidence is lacking. We hypothesized that the downsizing is directly caused by the ablative energy and subsequent scar formation.METHODS: We studied cardiac magnetic resonance imaging in 21 paroxysmal AF patients before and 3 months after successful PVI and in healthy sheep (n = 12) before and after PVI of the right PV only.RESULTS: PVI decreased the PV diameter in patients and sheep by 11.0(10.3) and 9.2(11.0)%, (p < 0.001 and p = 0.020), respectively. The control left PV in sheep were unchanged. A linear correlation existed between the extent of PV scar and PVI-induced decrease in PV diameter in patients.After PVI, the LA volume decreased (103(38) vs. 92(31)ml, pre- vs. post-ablation, respectively, p = 0.006), while the right atrial (RA) volume was unchanged in patients. A decrease in active emptying fraction after ablation (26.5(10.7) vs. 21.8(10.6)%, pre- vs. post-ablation, p = 0.031) was associated with reduced contractility of the PV walls (p = 0.004). The contractility of the LA walls was unaltered (p = 0.749).CONCLUSION: The ablation-induced PV diameter reduction was similar in patients with AF and healthy sheep without AF and was associated with PV scar extent. The volume only decreased in LA and not RA after PVI, and wall contractility decreased only in ablated sites. Therefore, the PVI-induced atrial downsizing is caused by the ablative energy and subsequent scar formation.

AB - BACKGROUND: Ablative pulmonary vein isolation (PVI) decreases pulmonary vein (PV) and left atrial (LA) dimensions in atrial fibrillation (AF) patients. These changes are attributed to reverse structural remodeling following sinus rhythm restoration but evidence is lacking. We hypothesized that the downsizing is directly caused by the ablative energy and subsequent scar formation.METHODS: We studied cardiac magnetic resonance imaging in 21 paroxysmal AF patients before and 3 months after successful PVI and in healthy sheep (n = 12) before and after PVI of the right PV only.RESULTS: PVI decreased the PV diameter in patients and sheep by 11.0(10.3) and 9.2(11.0)%, (p < 0.001 and p = 0.020), respectively. The control left PV in sheep were unchanged. A linear correlation existed between the extent of PV scar and PVI-induced decrease in PV diameter in patients.After PVI, the LA volume decreased (103(38) vs. 92(31)ml, pre- vs. post-ablation, respectively, p = 0.006), while the right atrial (RA) volume was unchanged in patients. A decrease in active emptying fraction after ablation (26.5(10.7) vs. 21.8(10.6)%, pre- vs. post-ablation, p = 0.031) was associated with reduced contractility of the PV walls (p = 0.004). The contractility of the LA walls was unaltered (p = 0.749).CONCLUSION: The ablation-induced PV diameter reduction was similar in patients with AF and healthy sheep without AF and was associated with PV scar extent. The volume only decreased in LA and not RA after PVI, and wall contractility decreased only in ablated sites. Therefore, the PVI-induced atrial downsizing is caused by the ablative energy and subsequent scar formation.

U2 - 10.1016/j.ijcha.2021.100894

DO - 10.1016/j.ijcha.2021.100894

M3 - Journal article

C2 - 34746362

VL - 37

SP - 100894

JO - IJC Heart and Vasculature

JF - IJC Heart and Vasculature

SN - 2352-9067

ER -