CARDIOVASCULAR JOURNAL OF AFRICA • Volume 33, No 3, May/June 2022 114 AFRICA AF cohort was 61 ± 10 years, 73.6% of the patients were male and 32.6% had long-standing persistent AF. The median AF duration was 11 months (interquartile range 3.0–48.8). The left atrial diameter (LAD) was 45 ± 5 mm and the LVEF was 65 ± 9%. AF conversion to SR directly (87.2%) or through AFL (12.8%) was achieved in 62.3% of the patients. Compared with ibutilide responders, non-responders were older and had a longer AF duration. No differences in LAD, LVEF, estimated glomerular filtration rate (eGFR), medical history, pre-ablation medications or post-ablation AAD were found between the two groups. Multivariate logistic regression analysis identified longer AF duration (odds ratio 1.009, 95% CI 1.002–1.017, p = 0.011) as a positive predictor of ibutilide non-responders (Table 2). PVI alone was performed in 72 (52.2%) patients, and the remaining 66 patients had PVI plus adjunctive linear ablation or SVC isolation. Left atrial roof linear ablation or mitral isthmus linear ablation were performed in 57 (41.3%) and 17 (12.3%) patients, respectively. Linear ablation of the cavotricuspid isthmus was performed in nine (6.5%) patients, while SVC isolation was added in two (1.4%). Compared to ibutilide responders, ibutilide non-responders had more frequent left atrial roof linear ablations (51.9 vs 34.9%, p = 0.049). No differences in the frequency of other types of linear ablation or SVC ablation were found between the two groups. During a median follow-up period of 610 days (IQR: 475– 1 106) post ablation, AAs recurred in 50 (36.2%) patients in the overall cohort after the initial CA [ibutilide responders, n = 26 (30.2%); ibutilide non-responders, n = 24 (46.2%)]. The HRs relating the time of arrhythmia recurrence to individual demographic and clinical factors after the initial CA are presented in Table 3. Among the factors, AF duration (HR 1.003, 95% CI 1.001– 1.006, p = 0.016), eGFR < 60 ml/min/1.73 m2 (HR 2.115, 95% CI 1.027–4.359, p = 0.042) and ibutilide non-responders (HR 2.204, 95% CI 1.159–3.454, p = 0.013) were significantly associated with AA recurrence. In the multivariate Cox proportional hazards analysis, only eGFR < 60 ml/min/1.73 m2 (HR 2.287, 95% CI 1.101–4.752, p = 0.027) and ibutilide non-responders (HR 1.994, 95% CI 1.117–3.561, p = 0.020) were independently associated with AA recurrence after CA. Kaplan–Meier analysis showed that the AA-free survival rates after the initial CA were significantly higher in the ibutilide responders than in the ibutilide non-responders (log-rank test, p = 0.011) (Fig. 2A). Table 2. Predictors of ibutilide non-responders in multivariate logistic regression analysis Predictors of ibutilide non-responders Odds ratio 95% CI p-value Age, per year 1.034 0.990–1.080 0.128 Male gender 0.492 0.198–1.226 0.128 Atrial fibrillation duration, per month 1.009 1.002–1.017 0.011 Left atrial diameter, per 1 mm 1.064 0.985–1.150 0.114 eGFR < 60 ml/min/1.73 m2 1.975 0.519–7.512 0.318 Pre-ablation AADs therapy 0.483 0.119–1.968 0.310 AADs, anti-arrhythmic drugs; CI, confidence interval; eGFR, estimated glomerular filtration rate. Table 1. Baseline characteristics of all included patients Baseline characteristics Total (n = 138) Ibutilide responders (n = 86) Ibutilide nonresponders (n = 52) p-value Age (years) 61 ± 10 59 ± 9 63 ± 10 0.038 Male gender, n (%) 103 (73.6) 67 (77.9) 36 (69.2) 0.256 Body mass index (kg/m2) 26.5 ± 3.0 26.6 ± 3.0 26.7 ± 3.2 0.900 Long-standing persistent AF, n (%) 45 (32.6) 21 (24.4) 24 (46.2) 0.008 AF duration (months), median (IQR) 11 (3.0–48.8) 5 (2.0–34.5) 17 (6.0–70.3) 0.004 Left atrial diameter (mm) 45 ± 5 44 ± 5 46 ± 5 0.107 LVEDD (mm) 49 ± 4 48 ± 4 49 ± 5 0.264 Left ventricular ejection fraction (%) 65 ± 9 64 ± 9 65 ± 8 0.501 eGFR < 60 ml/min/1.73 m2, n (%) 14 (10.1) 9 (10.5) 5 (9.6) 0.873 Medical history, n (%) Hypertension 77 (55.8) 48 (55.8) 29 (55.8) 0.996 Diabetes 31 (22.5) 21 (24.4) 10 (19.2) 0.479 Coronary disease 22 (15.9) 10 (11.6) 12 (23.1) 0.075 Cardiomyopathy 3 (2.2) 3 (3.5) 0 (0) 0.290 Heart failure 7 (5.1) 5 (5.8) 2 (3.8) 0.710 Hyperlipaemia 56 (40.6) 38 (44.2) 18 (34.6) 0.267 CHA2DS2-VASC score 1.7 ± 1.4 1.6 ± 1.4 1.9 ± 1.4 0.221 Pre-ablation medications, n (%) AADs 13 (9.4) 9 (10.5) 4 (7.7) 0.589 Beta-blocker 77 (55.8) 52 (60.5) 25 (48.1) 0.156 ACEI/ARB 41 (29.7) 25 (29.1) 16 (30.8) 0.832 Statins 40 (29.0) 24 (27.9) 16 (30.8) 0.719 Postablation AADs, n (%) No 14 (10.2) 8 (9.3) 6 (11.5) 0.619 Amiodarone 103 (74.6) 63 (73.3) 40 (77.0) Propafenone 21 (15.2) 15 (17.4) 6 (11.5) Reported as mean ± standard deviation, median (IQR), or n (%) AADs, anti-arrhythmic drugs; ACEI/ARB, angiotensin converting enzyme inhibitor or angiotensin receptor blocker; AF, atrial fibrillation; eGFR, estimated glomerular filtration rate; IQR, interquartile range; LVEDD, left ventricular enddiastolic dimension. Table 3. Clinical factors related to recurrence of atrial arrhythmia after the first catheter ablation Clinical factors Univariable analysis Multivariable analysis Hazard ratio (95% CI) p-value Hazard ratio (95% CI) p-value Age, per year 1.003 (0.973–1.035) 0.836 Male gender 0.645 (0.356–1.171) 0.150 Initial BMI, per unit 0.922 (0.840–1.013) 0.092 AF duration, per month 1.003 (1.001–1.006) 0.016 1.002 (1.000–1.005) 0.093 Left atrial diameter, per 1 mm 0.967 (0.921–1.017) 0.191 LVEF, per 1% 1.016 (0.980–1.054) 0.382 eGFR < 60 ml/ min/1.73 m2 2.115 (1.027–4.359) 0.042 2.287 (1.101–4.752) 0.027 Hypertension 0.607 (0.347–1.063) 0.081 CHA2DS2-VASc 1.027 (0.841–1.254) 0.794 Pre-ablation AADs therapy 1.982 (0.929–4.232) 0.077 Left atrial roof linear ablation 0.723 (0.405–1.290) 0.273 Ibutilide non-responders 2.204 (1.159–3.534) 0.013 1.994 (1.117–3.561) 0.020 Post-ablation AADs therapy Amiodarone vs no 0.639 (0.284–1.437) 0.279 Propafenone vs no 0.488 (0.171–1.393) 0.180 Amiodarone vs propafenone 1.310 (0.582–2.948) 0.515 AADs, anti-arrhythmic drugs; AF, atrial fibrillation; BMI, body mass index; CI, confidence interval; eGFR, estimated glomerular filtration rate; LVEF, left ventricular ejection fraction.
RkJQdWJsaXNoZXIy NDIzNzc=