Impact of transesophageal electrophysiologic study to elucidate the mechanism of arrhythmia on children with supraventricular tachycardia and no preexcitation.

An electrophysiologic study (EPS) of children and teenagers with paroxysmal supraventricular tachycardia (SVT) and normal electrocardiography (ECG) in sinus rhythm was evaluated. Generally, EPS is performed only before paroxysmal SVT ablation in these patients. In this study, 140 patients (mean age, 15 ± 3 years) with normal ECG in sinus rhythm were studied for SVT by a transesophageal route in baseline state and after isoproterenol. Idiopathic left or right ventricular tachycardia was diagnosed in four patients (3 %). Anterograde conduction over an atrioventricular (AV) left lateral (n = 10) or septal (n = 9) accessory pathway (AP) was noted in 19 patients (13.5 %) at atrial pacing. Orthodromic AV reentrant tachycardia (AVRT) was induced in these children. Five of the patients had a high rate conducted over AP (>240 bpm in baseline state or >290 bpm after isoproterenol). Two of the patients (a 10-year-old girl with well-tolerated SVT and a 17-year-old with syncope-related SVT) had the criteria for a malignant form with the induction of atrial fibrillation conducted over AP at a rate exceeding 290 bpm in baseline state. Of the 140 patients, 74 (53 %) had typical AV node reentrant tachycardia (AVNRT), nine had atypical AVNRT (6 %), 1 had atrial tachycardia (0.7 %), and 33 (23.5 %) had AVRT related to a concealed AP with only retrograde conduction. Electrophysiologic study is recommended for children with paroxysmal SVT and normal ECG in sinus rhythm. The data are helpful for guiding the treatment. Ventricular tachycardia or atrial tachycardia can be misdiagnosed. Masked preexcitation syndrome with anterograde conduction through AP was present in 13.5 % of the patients, and 1.4 % had a malignant preexcitation syndrome.

Sex-related differences in peri- and post-ablation clinical data for patients with atrial flutter.

UNLABELLED: Sex-related differences were not reported for the atrial flutter (AF). The purpose of the study was to look for the influence of gender on indications, clinical data and long-term results of AFl ablation. METHODS: 985 patients, [227 females (23%)] were referred for radiofrequency AFl ablation. Clinical history, echocardiography were collected. Patients were followed from 3 months to 10 years. RESULTS: Age of women and men was similar (65.5 ± 12 vs 64 ± 11.5 years). Underlying heart disease (HD) was as frequent in women as men (77.5 vs 77%), but women had more congenital HD (10 vs 2%;p<0.001), valvular HD (18 vs 10%;p<0.002), hypertensive HD (24 vs 18%;p<0.05), and less chronic lung disease (5 vs 10%;p<0.01), and ischemic HD (5 vs 20%;p<0.001). Atrial fibrillation (AF) history was more frequent in women (36 vs 27%;p<0.001). AFl-related tachycardiomyopathy (4.5 vs 8%;p<0.03) was more frequent, but 1/1 AFl (10 vs 6%;p=NS) as frequent. Failure of ablation (16 vs 10%;p<0.01), ablation-related major complications (3.5 vs 0.9%;p<0.005) were more frequent in women. After 3 ± 3 years, AFl recurrences were as frequent in women and men (10 vs 14%), AF occurrence more frequent in women (34 vs 19.5%; p<0.001). After excluding patients with previous AF, AF risk remained higher in women (19 vs 12%; p<0.004). CONCLUSIONS: In patients admitted for ablation, AFL was less common in women than in men, despite similar age and similarly prevalent HD. More than men, women had frequent AF history, a higher risk of failure of ablation and AFl ablation-related major complications and a higher risk of AF after ablation.

Influence of the time on the prevalence of drug-related resuscitated sudden death during these past 20 years.

UNLABELLED: The use of drugs is the subject of numerous recommendations. The purpose of this study was to evaluate the prevalence of drug-related sudden deaths (SD) and the possible changes during these past 20 years. METHODS: 271 patients, 205 men, 66 women aged from 12 to 88 years (mean 59 ± 15) were admitted after SD resuscitation outside the acute phase of myocardial infarction, 146 before 2000 (group I), 125 between 2000 and 2010 (group II). Complete check-up was performed. RESULTS: Ischemic HD (41%) vs (37%), idiopathic dilated cardiomyopathy (12%) vs (11%), various HD (5%) vs (8%) were as frequent in groups I and II. Valvular HDs were more frequent in group I than II (12%) vs 6% (p<0.01). Abnormalities at ECG (preexcitation syndrome, conduction disturbance, atrial fibrillation or ion channel disorders) were less frequent in group I than II (8%) vs (18%) (p<0.02). Drug-facilitated or related SD's did not change in groups I and II: 54 patients presented a drug-related ventricular fibrillation or asystole, 16% in group I and 24% (NS) in group II. SD was caused by hypokalemia, QT interval increase or conduction disturbance. HD or abnormal ECG was present in 42 patients. Digoxin, diuretics, calcium inhibitors, betablockers, antiarrhythmic drugs alone or in association were mainly implicated. CONCLUSION: Drug-related arrhythmias continue to explain or favour at least 20% of SDs. Despite numerous recommendations on the use of drugs, the prevalence of fatal events that may be attributed to a cardiovascular drug does not decrease between the years before 2000 and after 2000.

Does syncope require rhythmic and non-rhythmic evaluation in patients with previous MI?

BACKGROUND: Multiple factors, in addition to left ventricular ejection fraction (LVEF) influence the risk of mortality in coronary artery disease. The purpose of this study was to evaluate the main causes of syncope after myocardial infarction (MI) and to propose an algorithm of management. METHODS: 356 patients consecutively admitted for syncope and history of MI (>1 month), without ventricular tachycardia (VT), underwent echocardiography, Holter monitoring, head-up tilt test, exercise testing, signal-averaged ECG, electrophysiological study (EPS) and evaluation of coronary status. The mean follow-up was 4±2 years. RESULTS: Monomorphic VT, ventricular flutter or fibrillation (VF) and supraventricular tachyarrhythmia were respectively induced at EPS in 87, 63 and 39 patients; conduction disturbances were noted in 23 patients, and 57 patients had several abnormalities. Among the 144 patients with negative EPS, coronary ischaemia was identified in 37 patients, and hypervagotonia in 27 patients. All studies remain negative in 84 patients (23.6%), more frequently women (p<0.001). Four patients died suddenly during follow-up. A longer QRS duration, a lower LVEF and grade IVa,b of Lown on Holter ECG were associated with the induction of VT. LVEF<40% and VT/VF induction were predictors of cardiac mortality, VT was a predictor of sudden death, and low LVEF and advanced age were predictors of death by heart failure. CONCLUSION: Myocardial ischaemia, hypervagotonia, conduction abnormalities, ventricular or supraventricular tachyarrhythmias were identified in 76% of patients with syncope after MI. Several factors of syncope were found in 57 patients (16%). Non-invasive rhythmological and systematic coronary status assessment should be recommended in patients with syncope following MI.

[Complete electrophysiological study remains necessary in symptomatic advanced cardiomyopathy]. / Une étude électrophysiologique complète reste nécessaire dans une cardiopathie évoluée symptomatique.

Multiple mechanisms can explain a tachycardia associated or not with a heart disease. It is important to establish its origin, particularly if advanced heart disease is present, for the treatment. Complete electrophysiological study remains an important means of diagnosis. We report the case of a 39-year old man, who had a dilated cardiomyopathy since the age of 25 years and who complained of tachycardia. These symptoms were shown to be related to atrioventricular nodal re-entrant tachycardia at electrophysiological study and a specific treatment was indicated.