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Electromechanical interaction, with prolonged QRS duration due to right ventricular (RV) overload, has been described as a predictor of unfavorable outcome in patients late after correction of Tetralogy of Fallot (TOF). Aim of our study was to evaluate myocardial function and activation delay of both left and right ventricles in TOF patients. Doppler echo, treadmill test and pulsed Tissue Doppler (TD) were performed in 25 healthy subjects and in 30 adult patients who had undergone surgery for TOF, all with right bundle branch block on ECG. Exclusion criteria were evidence of residual pulmonary either stenosis or regurgitation. By use of TD, the level of both LV mitral and RV tricuspid annulus were measured: systolic (Sm), early- and late-diastolic (Em and Am) regional peak velocities. The indexes of myocardial systolic activation were calculated: precontraction time (PCTm) and interventricular activation delay (InterV-del) (difference of PCTm between RV and LV segments). The two groups were comparable for LV diameters and for Doppler indexes, while QRS duration was prolonged and RV end-diastolic diameter was increased in TOF. By TD analysis, only at the level of tricuspid annulus TOF patients had lower Sm and Em, and increased RV PCTm ( p<0.001 ) and InterV-del ( p<0.0001 ), even after adjustment for heart rate (HR) and QRS duration. By treadmill test, TOF showed reduced cardiac functional reserve. In seven patients non-sustained ventricular tachycardia was documented during physical effort. By multivariate analysis, RV Em ( p<0.001 ), and InterV-del ( p<0.01 ) were independently associated to maximal workload at peak effort. The same InterV-del was an independent determinant of risk of ventricular arrhythmias during effort ( p<0.01 ). A cut-off point of Em peak velocity of tricuspid annulus <0.13 m/s at rest showed a sensitivity of 91% and a specificity of 88% in identifying TOF patients with submaximal exercise test. A cut-off point of InterV-del >55 ms showed 87% sensitivity and 88% specificity to detect increased risk of ventricular arrhythmias during effort. In TOF patients, TD analysis at rest may be taken into account as a non-invasive and easy-repeatable tool to predict cardiac performance during physical effort, and to select subgroups of patients at increased risk of ventricular arrhythmias. [ABSTRACT FROM AUTHOR]

Electromechanical interaction, with prolonged QRS duration due to right ventricular (RV) overload, has been described as a predictor of unfavorable outcome in patients late after correction of Tetralogy of Fallot (TOF). Aim of our study was to evaluate myocardial function and activation delay of both left and right ventricles in TOF patients. Doppler echo, treadmill test and pulsed Tissue Doppler (TD) were performed in 25 healthy subjects and in 30 adult patients who had undergone surgery for TOF, all with right bundle branch block on ECG. Exclusion criteria were evidence of residual pulmonary either stenosis or regurgitation. By use of TD, the level of both LV mitral and RV tricuspid annulus were measured: systolic (Sm), early- and late-diastolic (Em and Am) regional peak velocities. The indexes of myocardial systolic activation were calculated: precontraction time (PCTm) and interventricular activation delay (InterV-del) (difference of PCTm between RV and LV segments). The two groups were comparable for LV diameters and for Doppler indexes, while QRS duration was prolonged and RV end-diastolic diameter was increased in TOF. By TD analysis, only at the level of tricuspid annulus TOF patients had lower Sm and Em, and increased RV PCTm (p<0.001) and InterV-del (p<0.0001), even after adjustment for heart rate (HR) and QRS duration. By treadmill test, TOF showed reduced cardiac functional reserve. In seven patients non-sustained ventricular tachycardia was documented during physical effort. By multivariate analysis, RV Em (p<0.001), and InterV-del (p<0.01) were independently associated to maximal workload at peak effort. The same InterV-del was an independent determinant of risk of ventricular arrhythmias during effort (p<0.01). A cut-off point of Em peak velocity of tricuspid annulus <0.13 m/s at rest showed a sensitivity of 91% and a specificity of 88% in identifying TOF patients with submaximal exercise test. A cut-off point of InterV-del >55 ms showed 87% sensitivity and 88% specificity to detect increased risk of ventricular arrhythmias during effort. In TOF patients, TD analysis at rest may be taken into account as a non-invasive and easy-repeatable tool to predict cardiac performance during physical effort, and to select subgroups of patients at increased risk of ventricular arrhythmias. [ABSTRACT FROM AUTHOR]

Purpose Radiofrequency catheter ablation (RFCA) of the postero-septal accessory pathways (AP) has been reported to be more difficult than for AP located in other areas. Aim of the study was to evaluate the efficacy and risks of RFCA of postero-septal AP in a single centre paediatric population. Methods Between January 2002 and March 2005, 20 patients (9M/11F, aged 11-17 years, mean age 15±2.6) with a postero-septal AP underwent attempt to RFCA. Results In the 20 pts with a postero-septal AP (12 with overt ventricular pre-excitation and 8 with concealed by-pass tract) RF was delivered in the earliest site of activation on the mitral or tricuspidal annulus. Only a patient showed an AP with decremental conduction properties. Time of procedure, was 145±56min and time of radiation exposure was 58±22 min. Successful RF pulses were delivered on right postero-septal area in 8 pts, on left postero-septal area in 3 pts, in the proximal coronary sinus in 6 pts. True epicardial postero-septal AP was found in 3 pts, and the RFCA was considered to be not feasible. Four weeks and 12 weeks after RFCA all patients underwent a non-invasive evaluation. Only a patient underwent a second procedure for recurrence of arrhythmias. Conclusion RFCA of postero-septal AP in paediatric age is technically challenging. More RF pulses, longer procedure time and longer radiation exposure are needed to achieve successful results, and recurrences of AP conduction are not unusual. [ABSTRACT FROM PUBLISHER]

Background Fetal arrhythmia occurs in ∼1-2% of all pregnancies. Compared with the general population, fetuses with a cardiac arrhythmia (CA) have high perinatal and neonatal mortality rates. Diagnosis and management of CA in the fetal age is crucial for the prevention of heart failure. Aim To evaluate the management protocol of fetal CA based on prior identification of the underlying mechanism of the arrhythmias. Methods In the last two years 566 fetuses with suspicious cardiac malformation were evaluated with echocardiography in our centre. Rhythm diagnosis was done by performing M mode, pulsed and continuous Doppler and tissue Doppler through the fetal heart so that both the ventricular and atrial activity were recorded. Results Thirty-three out of 566 fetuses showed cardiac arrhythmias (mean weeks of gestation at diagnosis: 24,3±4,5). Two out of 33 had fetal hydrops and one, despite medical therapy, died at 28 weeks. The weight at birth of survived 32 was 2920±320 gr. One fetus with tachycardia had a congenital heart disease (Ebstein anomaly). The supposed prenatal diagnosis was confirmed at the birth in 29/33 fetuses. Nineteen fetuses had tachycardia with a 1:1 AV conduction during fetal life (HR 225±25 bpm). Ten out of 19 showing a 1:1 AV conduction, had a long VA' interval; the diagnosis at the birth were: 1 inappropriate sinus tachycardia, 5 persistent junctional reciprocating tachycardia (PJRT) and 4 atrial ectopic tachycardia (AET). Nine out of 19 fetuses showing a 1:1 AV conduction had a short VA' interval; the diagnosis at the birth was atrioventricular re-entrant tachycardia (AVRT). One fetus had atrial tachycardia with a 2:1 AV conduction (atrial flutter). Six fetuses showed isolated ectopic beats. Four fetuses showed AV dissociation with a low ventricular rate (HR 42±18 bpm); in all at the birth the diagnosis of complete AV block was confirmed and two underwent epicardial pacemaker implanting (at 3 and 7 months). One, with a familiarity for long QT syndrome (LQTS), showed a fetal tachycardia with AV dissociation; at the birth it was confirmed the diagnosis of LQTS and recurrent ventricular tachycardia. In fetal life therapeutical approach (maternal administration of digoxin, sotalol or flecainide for fetuses with sustained supraventricular tachycardia) was decided according to the supposed electrophysiological mechanism. Conclusion Fetal echocardiography could clarify the electrophysiological mechanism of fetal cardiac arrhythmias and guide the therapeutic approach. [ABSTRACT FROM PUBLISHER]