Influence of the mode of management of acute myocardial infarction on the inducibility of ventricular tachyarrhythmias with programmed ventricular stimulation after myocardial infarction.

BACKGROUND: Programmed ventricular stimulation (PVS) is a technique for screening patients at risk for ventricular tachycardia (VT) after myocardial infarction (MI), but the results might be difficult to interpret. OBJECTIVES: To investigate the results of PVS after MI, according to date of completion. METHODS: PVS results were interpreted according to the mode of MI management in 801 asymptomatic patients: 301 (group I) during the period 1982-1989, 315 (group II) during 1990-1999, and 185 (group III) during 2000-2010. The periods were chosen based on changes in MI management. Angiotensin-converting enzyme (ACE) inhibitors had been given since 1990; primary angioplasty was performed routinely since 2000. The PVS protocol was the same throughout the whole study period. RESULTS: Group III was older (61 +/- 11 years) than groups I (56 +/- 11) and II (58 +/- 11) (P < 0.002). Left ventricular ejection fraction (LVEF) was lower in group III (36.5 +/- 11%) than in groups I (44 +/- 15) and II (41 +/- 12) (P < 0.000). Monomorphic VT < 270 beats/min was induced as frequently in group III (28%) as in group II (22.5%) but more frequently than in group I (20%) (P < 0.03). Ventricular fibrillation and flutter (VF) was induced less frequently in group III (14%) than in groups I (28%) (P < 0.0004) and II (30%) (P < 0.0000). Low left ventricular ejection fraction (LVEF) and date of inclusion (before/after 2000) were predictors of VT or VF induction on multivariate analysis. CONCLUSIONS: Induction of non-specific arrhythmias (ventricular flutter and fibrillation) was less frequent than before 2000, despite the indication of PVS in patients with lower LVEF. This decrease could be due to the increased use of systematic primary angioplasty for MI since 2000.

Rapid and low-cost method to prove the nature of no documented tachycardia in children and teenagers without pre-excitation syndrome.

Aims Symptoms in children are often difficult to interpret. The purpose of this study was to report the results of transoesophageal electrophysiological study (EPS) performed in children complaining of sudden onset tachycardia with normal non-invasive studies. Methods and results Eighty-two children and teenagers (mean age 15 +/- 3 years) presented with suspected but no documented paroxysmal supraventricular tachycardia (SVT). ECG was normal. Non-invasive studies were negative; 23 children had syncope with tachycardias. They underwent transoesophageal EPS in our out-patient clinic. The mean duration of transoesophageal EPS was 11 +/- 5 min. Electrophysiological study was negative in 25 children. AV nodal re-entrant tachycardia could be induced in 37 children, 11 of them associated with syncope. Wolff-Parkinson-White syndrome (WPW) was diagnosed in five children in which atrioventricular re-entrant tachycardia was inducible. Atrioventricular re-entrant tachycardia due to a concealed AP was induced in 14 children. Verapamil-sensitive ventricular tachycardia was induced in one patient. Factors associated with tachycardia inducibility were an older age (15.5 +/- 2 vs. 14 +/- 4 years) (P < 0.05) and the absence of syncope (81 vs. 52%) (P < 0.05). During a mean follow-up of 3 +/- 1 year, no patient with negative EPS developed documented tachycardia. In 17 children with inducible SVT, radiofrequency ablation of the re-entrant circuit was subsequently performed. Conclusion Transoesophageal EPS is a fast method for proving the nature of paroxysmal tachycardia in children and teenagers presenting with normal ECG and for demonstrating WPW syndrome not visible on standard ECG. The negative predictive value of transoesophageal EPS for the diagnosis of SVT was 100%.