Risk of atrial fibrillation after atrial flutter ablation: impact of AF history, gender, and antiarrhythmic drug medication.

INTRODUCTION: Atrial fibrillation (AF) and flutter (AFL) are frequently associated. We assessed the frequency and identified the predictors of AF occurrence after AFL ablation. METHODS AND RESULTS: A total of 1,121 patients referred for AFL ablation were followed for a mean duration of 2.1 ± 2.7 years. Antiarrhythmic drugs were stopped after ablation in patients with no AF prior to ablation, or continued otherwise. A total of 356 patients (31.7%) had a history of AF prior to AFL ablation. Patients with AF prior to ablation were more likely to be females (OR = 1.35, CI = 1.00-1.83, P = 0.05). After ablation, 260 (23.2%) patients experienced AF. In the multivariable model, AF prior to ablation (OR = 1.90, CI = 1.42-2.54, P < 0.001) and female gender (OR = 1.77, CI = 1.29-2.42, P < 0.001) were associated with a higher risk of AF after ablation. In patients without prior AF, class I antiarrhythmics and amiodarone prior to AFL ablation were independently associated with higher risk of AF after ablation (OR = 2.11, CI = 1.15-3.88, P = 0.02 and OR = 1.60, CI = 1.08-2.36, P = 0.02, respectively). In patients who experienced AF after ablation, 201/260 (77.3%) had a CHA2DS2-VASc ≥1. Two patients with AF prior to ablation had a stroke during the follow-up whereas none of the patients without AF prior to ablation had a stroke. CONCLUSIONS: AF occurrence after AFL ablation is frequent (>20%), especially in patients with a history of AF, in female patients, and in patients treated with class I antiarrythmics/amiodarone prior to AFL. Since most patients who experience AF after AFL ablation have a CHA2DS2-VASc ≥1, the decision to stop anticoagulants after ablation should be considered on an individual basis.

Incidence and prognostic significance of spontaneous and inducible antidromic tachycardia.

AIMS: Orthodromic atrioventricular reentrant tachycardia (ORT) is the most common arrhythmia at electrophysiological study (EPS) in patients with pre-excitation. The purpose of the study was to determine the clinical significance and the electrophysiological characteristics of patients with inducible antidromic tachycardia (ADT). METHODS AND RESULTS: Electrophysiological study was performed in 807 patients with a pre-excitation syndrome in control state and after isoproterenol. Antidromic tachycardia was induced in 63 patients (8%). Clinical and electrophysiological data were compared with those of 744 patients without ADT. Patients with and without ADT were similar in term of age (33 ± 18 vs. 34 ± 17), male gender (68 vs. 61%), clinical presentation with spontaneous atrioventricular reentrant tachycardia (AVRT) (35 vs. 42%), atrial fibrillation (AF) (3 vs. 3%), syncope (16 vs. 12%). In patients with induced ADT, asymptomatic patients were less frequent (24 vs. 37%; <0.04), spontaneous ADT and spontaneous malignant form more frequent (8 vs. 0.5%; <0.001) (16 vs. 6%; <0.002). Left lateral accessory pathway (AP) location was more frequent (51 vs. 36%; P < 0.022), septal location less frequent (40 vs. 56%; P < 0.01). And 1/1 conduction through AP was more rapid. Orthodromic AVRT induction was as frequent (55.5 vs. 55%), but AF induction (41 vs. 24%; P < 0.002) and electrophysiological malignant form were more frequent (22 vs. 12%; P < 0.02). The follow-up was similar; four deaths and three spontaneous malignant forms occurred in patients without ADT. When population was divided based on age (<20/≥20 years), the older group was less likely to have criteria for malignant form. CONCLUSION: Antidromic tachycardia induction is rare in pre-excitation syndrome and generally is associated with spontaneous or electrophysiological malignant form, but clinical outcome does not differ.

Factors likely to affect the long-term results of ventricular stimulation after myocardial infarction.

BACKGROUND: The results of programmed ventricular stimulation (PVS) may change after myocardial infarction (MI). The objective was to study the factors that could predict the results of a second PVS. METHODS: Left ventricular ejection fraction (LVEF) and QRS duration were determined and PVS performed within 3 to 14 years of one another (mean 7.5+/-5) in 50 patients studied systematically between 1 and 3 months after acute MI. RESULTS: QRS duration increased from 120+/-23 ms to 132+/-29 (p 0.04). LVEF did not decrease significantly (36+/-12 % vs 37+/-13 %). Ventricular tachycardia with cycle length (CL) > 220ms (VT) was induced in 11 patients at PVS 1, who had inducible VT with a CL > 220 ms (8) or < 220 ms (ventricular flutter, VFl) (3) at PVS 2. VFl or fibrillation (VF) was induced in 14 patients at PVS 1 and remained inducible in 5; 5 patients had inducible VT and 4 had a negative 2nd PVS. 2. 25 patients had initially negative PVS; 7 had secondarily inducible VT, 4 a VFl/VF, 14 a negative PVS. Changes of PVS were related to initially increasing QRS duration and secondarily changes in LVEF and revascularization but not to the number of extrastimuli required to induce VFl. CONCLUSIONS: In patients without induced VT at first study, changes of PVS are possible during the life. Patients with initially long QRS duration and those who developed decreased LVEF are more at risk to have inducible monomorphic VT at 2nd study, than other patients.

Are the results of electrophysiological study different in patients with a pre-excitation syndrome, with and without syncope?

AIMS: Syncope in Wolff-Parkinson-White (WPW) syndrome may reveal an arrhythmic event or is not WPW syndrome related. The aim of the study is to evaluate the results of electrophysiological study in WPW syndrome according to the presence or not of syncope and the possible causes of syncope. METHODS AND RESULTS: Among 518 consecutive patients with diagnosis of WPW syndrome, 71 patients, mean age 34.5 +/- 17, presented syncope. Transoesophageal electrophysiological study in control state and after isoproterenol infusion was performed in the out-patient clinic. Atrioventricular re-entrant tachycardia (AVRT) was more frequently induced than in asymptomatic patients (n = 38, 53.5%, P < 0.01), less frequently than in those with tachycardia; atrial fibrillation (AF) and/or antidromic tachycardia (ATD) was induced in 28 patients (39%) more frequently (P < 0.05) than in asymptomatic patients or those with tachycardia. The incidence of high-risk form [rapid conduction over accessory pathway (AP) and AF or ATD induction] was higher in syncope group (n = 18, 25%, P < 0.001) than in asymptomatic subjects (8%) or those with tachycardias (7.5%). Maximal rate conducted over AP was similar in patients with and without syncope, and higher in patients with spontaneous AF, but without syncope. Results were not age-related. CONCLUSION: Tachycardia inducibility was higher in patients with syncope than in the asymptomatic group. The incidence of malignant WPW syndrome was higher in patients with syncope than in asymptomatic or symptomatic population, but the maximal rate conducted over AP was not higher and another mechanism could be also implicated in the mechanism of syncope.

Prediction of atrial fibrillation in patients with supraventricular tachyarrhythmias treated with catheter ablation or not. Classical scores are not useful.

BACKGROUND: Atrial fibrillation (AF) and other supraventricular tachyarrhythmias (SVTA) [atrial flutter (AFL), atrioventricular nodal reentrant tachycardia (AVNRT), atrioventricular reentrant tachycardia (AVRT) and preexcitation syndrome (PS)] are frequently associated. We assessed the AF occurrence frequency and predictors according to the nature of SVTA and completion of SVTA ablation. METHODS AND RESULTS: 4169 patients were referred for SVTA (typical AVNRT: 1338, AVRT over a concealed accessory pathway: 329, atypical AVNRT: 205, AFL: 1321; PS: 976); mean age was 50±20years; electrophysiological study (EPS) was systematic; patients were followed for a mean duration of 3±4.5years. Ablation of SVTA was performed in 2949 patients (71%) and 1220 patients were not treated or treated with antiarrhythmic drugs. AF developed in 469 patients (11.2%). In the multivariable model, AF prior to ablation, history of AF, nature of SVTA (AFL), and presence of heart disease were associated with a high risk of AF during follow-up. Presence of heart failure, old age, diabetes and vascular disease were not predictive of AF. Ablation was a weak but significant factor of AF prevention. A score based on nature of SVTA, presence of heart disease and history of AF is proposed. CONCLUSIONS: AF occurrence in patients with SVTA cannot be predicted by the presence of heart failure, old age, diabetes and vascular disease, but only by the following criteria, presence of heart disease, history of AF and nature of the SVTA (SVTA).

Missing diagnosis of preexcitation syndrome on ECG: clinical and electrophysiological significance.

UNLABELLED: Electrocardiographic criteria of preexcitation syndrome are sometimes not visible on ECG in sinus rhythm (SR). The purpose of the study was to evaluate the significance of unapparent preexcitation syndrome in SR, when overt conduction through accessory pathway (AP) was noted at atrial pacing. METHODS: Anterograde conduction through atrioventricular AP was identified at electrophysiological study (EPS) in 712 patients, studied for tachycardia (n=316), syncope (n=89) or life-threatening arrhythmia (n=55) or asymptomatic preexcitation syndrome (n=252). ECG in SR at the time of EPS was analysed. RESULTS: 78 patients (11%) (group I) had a normal ECG in SR and anterograde conduction over AP at atrial pacing; 634 (group II) had overt preexcitation in SR. Group I was as frequently asymptomatic (35%) as group II (35%), had as frequently tachycardias, syncope or life-threatening arrhythmia as group II (43, 5, 2% vs 43, 13, 8%). AP was more frequently left lateral in group I (57%) than in group II (36%)(p<0.001). AV re-entrant tachycardia, atrial fibrillation (AF), antidromic tachycardia were induced as frequently in group I (54, 18, 10%) as in group II (54, 27, 7%). Malignant forms (induced AF with RR intervals between preexcited beats <250ms in control state or <200ms after isoproterenol) were as frequent in group I (11.5%) as II (14%). CONCLUSIONS: The frequency of unapparent preexcitation syndrome represents 11% of our population with anterograde conduction through an AP and could be underestimated. The risk to have a malignant form is as high as in patients with overt preexcitation syndrome in SR.

1:1 atrial-flutter. Prevalence and clinical characteristics.

UNLABELLED: Little is known about the epidemiology of 1:1 atrial flutter (AFL). Our objectives were to determine its prevalence and predisposing conditions. METHODS: 1037 patients aged 16 to 93 years (mean 64±12) were consecutively referred for AFL ablation. 791 had heart disease (HD). Patients admitted with 1/1 AFL were collected. Patients were followed 3±3 years. RESULTS: 1:1 AFL-related tachycardiomyopathy was found in 85 patients, 59 men (69%) with a mean age of 59±12 years. The prevalence was 8%. They were compared to 952 patients, 741 men (78%, 0.04), with a mean age of 65±12 years (0.002) without 1:1 AFL. Factors favoring 1:1 AFL was the absence of HD (35 vs 23%, 0.006), the history of AF (42 vs 30.5%)(0.025) and the use of class I antiarrhythmic drugs (34 vs 13%)(p<0.0001), while use of amiodarone or beta blockers was less frequent in patients with 1:1 AFL (5, 3.5%) than in patients without 1:1 AFL (25, 15%) (p<0.0001, 0.03). The failure of ablation (9.4 vs 11%), ablation-related complications (2.3 vs 1.4%), risk of subsequent atrial fibrillation (AF) (20 vs 24%), risk of AFL recurrences (19 vs 13%) and risk of cardiac death (5 vs 6%) were similar in patients with and without 1:1 AFL. CONCLUSIONS: The prevalence of 1:1 AFL in patients admitted for AFL ablation was 8%. These patients were younger, had less frequent HD, had more frequent history of AF and received more frequently class I antiarrhythmic drugs than patients without 1:1 AFL. Their prognosis was similar to patients without 1:1 AFL.

Risk of atrial fibrillation according to the initial presentation of a preexcitation syndrome.

BACKGROUND: Atrioventricular reentrant tachycardia (AVRT) is frequent in Wolff-Parkinson-White syndrome (WPW). Atrial fibrillation (AF) is rare. The purpose of the study was to determine the factors of spontaneous AF in WPW according to the initial presentation. METHODS AND RESULTS: Electrophysiological study (EPS) was performed among 709 patients with a preexcitation syndrome. First event was AF in 44 patients. Remaining patients were studied for AVRT (314), syncope (94), adverse presentation without AF (9) or systematically (248 asymptomatic patients). Patients with AF were older than other patients (44 ± 16 years vs 34.5 ± 17) (0.0003); maximal rate conducted over accessory pathway (AP) was higher in patients with AF than in other patients except in adverse presentation (0.0002); AVRT was induced more frequently in patients with AF than in asymptomatic patients (57% vs 14.5%) but less than in patients with AVRT (89%). AF was induced more frequently in patients with AF than in other patients except in adverse presentation (<0.0001). During follow-up AF occurred more frequently in patients with AF (5; 11%) than in patients with AVRT (7; 2%), with syncope (1%) and asymptomatic patients (4; 1.6%). Older age predicted recurrence (54 ± 16 vs 40 ± 17). CONCLUSIONS: AF was the first event in only 6% of patients with WPW and was a rare event in other patients. They are older but 10% are less than 18 years and have a more rapid conduction over AP than other patients.