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, J. rôme
AU - Lamy, J. rôme
AU - Kachenoura, Nadjia
AU - Constantin, Marion
AU - Quesson, Bruno
AU - Cochet, Hubert
AU - Coronel, Ruben
AU - Dekker, Lukas R. C.
N1 - Funding Information: We thank Medtronic for proving the ablation catheters for the animal experiments. This work was supported by Medtronic (unrestricted research grant, recipient LRCD, Catharina Hospital (research grant, recipient LRCD), and Leducq Foundation Rhythm [16CVD02] (grant recipient RC). Publisher Copyright: © 2021 The Authors
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.
KW - Ablation scar
KW - Atrial contractility
KW - Atrial fibrillation
KW - Cardiac magnetic resonance
KW - Pulmonary vein isolation
UR - https://www.scopus.com/inward/record.uri?partnerID=HzOxMe3b&scp=85121984169&origin=inward
UR - https://www.ncbi.nlm.nih.gov/pubmed/34746362
U2 - https://doi.org/10.1016/j.ijcha.2021.100894
DO - https://doi.org/10.1016/j.ijcha.2021.100894
M3 - Article
C2 - 34746362
SN - 2352-9067
VL - 37
SP - 100894
JO - International journal of cardiology. Heart & vasculature
JF - International journal of cardiology. Heart & vasculature
M1 - 100894
ER -