Pietro Turco

Pretreatment with verapamil in patients with persistent or chronic atrial fibrillation who underwent electrical cardioversion

OBJECTIVES To evaluate, in a prospective and randomized fashion, the efficacy of a pretreatment with verapamil (V) in reducing recurrences of atrial fibrillation (AF) after electrical cardioversion (C). BACKGROUND The increased vulnerability for AF recurrence is probably due to AF-induced changes in the electrophysiologic properties of the atria. This electrical remodeling seems to be due to intracellular calcium overload. METHODS One hundred seven patients with persistent or chronic AF underwent external and/or internal C. All patients received oral propafenone (P) (900 mg/day) three days before and during the entire period of follow-up (three months). In the first group, patients received only the P. In the second group, in adjunct to P, oral V (240 mg/day) was initiated three days before C and continued during the follow-up. Finally, in the third group, oral V was administered three days before and continued only for three days after electrical C. RESULTS During the three months of follow-up, 23 patients (23.7%) had AF recurrence. Mantel-Haenszel cumulative chi-square reached a significant level only when comparing AF free survival curves of group I versus group II and group III (chi-square = 5.2 and 4, respectively; p < 0.05). Significantly, 15 (65.2%) AF relapses occurred during the first week after cardioversion with a higher incidence in group I (10/33 patients, 30.3%) than group II (2/34 patients, 5.9%; p = 0.01) and group III (3/30 patients, 10%; p = 0.04). CONCLUSIONS Six days of oral V administration centered on the C day, combined with P, significantly reduce the incidence of early recurrences of AF compared with P alone.

Predictive Value of Early Atrial Tachyarrhythmias Recurrence After Circumferential Anatomical Pulmonary Vein Ablation

Objective: Radiofrequency (RF) ablation at the ostia of the pulmonary veins (PVs) to cure atrial fibrillation (AF) is often followed by early AF recurrence. The aims of this study were to determine the rate of early atrial tachyarrhythmia as recurrence after circumferential anatomical PV ablation; to evaluate whether the early recurrence of atrial tachyarrhythmias correlates with the long‐term outcome of ablation; and to identify the predictors of early atrial tachyarrhythmias relapse.

VErapamil Plus Antiarrhythmic drugs Reduce Atrial Fibrillation recurrences after an electrical cardioversion (VEPARAF Study)

AIMS To evaluate the impact, on atrial fibrillation (AF) recurrences, of verapamil addition to a class IC or III antiarrhythmic drug in patients, with persistent AF, who underwent an electrical cardioversion (EC). METHODS AND RESULTS Three hundred sixty-three patients were randomized to receive four different pre-treatment protocols: oral amiodarone (group A), oral flecainide (group F), oral amiodarone plus oral verapamil (group A+V), oral flecainide plus oral verapamil (group F+V). Patients who showed an AF recurrence within 3 months were assigned to the alternative group and underwent a second EC after 48h. During 3 months of follow-up, 89 patients (27.5%) had an AF recurrence. By univariate analysis, verapamil reduced AF recurrences if added to amiodarone or flecainide (from 35% to 20%, P=0.004). Applying Cox proportional hazards regression model, only the younger age, the shorter duration of AF, and the use of verapamil were predictor of maintenance of sinus rhythm after cardioversion. In patients with primary AF recurrence, verapamil addition to group A and F patients, significantly decreased secondary AF recurrence rate as compared to group A+V and F+V patients who stopped the verapamil therapy (68% vs 88%, P=0.03). CONCLUSIONS The addition of verapamil to class IC or III antiarrhythmic drug significantly reduced the AF recurrences, that were more frequent in older patients and in patients with longer lasting AF; moreover, verapamil was effective in reducing the secondary AF recurrences, too.

Role of catheter-induced mechanical trauma in localization of target sites of radiofrequency ablation in automatic atrial tachycardia

OBJECTIVES We compared the efficacy of two different mapping techniques in identifying the ablation site for atrial tachycardia. Moreover, we evaluated the additive positive predictive value of mechanical interruption of atrial tachycardia to reduce the number of ineffective radiofrequency applications. BACKGROUND Radiofrequency catheter ablation has been suggested as a highly effective technique to treat drug-resistant atrial tachycardia. However, irrespective of the mapping technique utilized, success was most often achieved with a large number of radiofrequency applications. METHODS Forty-five patients with atrial tachycardia underwent radiofrequency catheter ablation. Mapping techniques included identification of earliest atrial activation and pace-mapping concordant sequence. RESULTS Atrial tachycardia was successfully treated in 42 (93.3%) of 45 patients with a mean of 3.9 radiofrequency pulses/patient. An interval between the onset of the intracavitary atrial deflection and the onset of the P wave during atrial tachycardia (AP interval) > or = 30 ms (p < 0.001) and pace-mapping concordant sequence (p = 0.01) were all significant predictors of outcome. An AP interval > or = 30 ms and a pace-mapping concordant sequence were highly sensitive (92.8%, 95% confidence interval [CI] 80.5% to 98.5%; 85.7%, 95% CI 71.5% to 94.6%, respectively) but less specific (47.8%, 95% CI 37.9% to 58.2%, 36.8%, 95% CI 27.6% to 47.2%, respectively) in identifying the site of ablation. By using atrial tachycardia mechanical interruption combined with the AP interval >30 ms or the pace-mapping concordant sequence, we obtained a specifically of 76.5% (95% CI 66.4% to 84.0%) and 73.5% (95% CI 63.2% to 81.4%), respectively, and a positive predictive value of 49.2% and 44.6%, respectively. CONCLUSIONS An AP interval > or = 30 ms and a pace-mapping concordant sequence were reliable mapping features for predicting the outcome of the ablation procedure. Mechanical interruption of atrial tachycardia improved the specificity and positive predictive value of these two mapping techniques.

Response to flecainide infusion predicts long-term success of hybrid pharmacologic and ablation therapy in patients with atrial fibrillation.

OBJECTIVES We tested the hypothesis that the response to flecainide infusion can identify patients with atrial fibrillation (AF) in whom the hybrid pharmacologic and ablation therapy reduces the recurrences of AF. BACKGROUND Infusion of class IC anti-arrhythmic drugs may promote transformation of AF into atrial flutter. Catheter ablation of atrial flutter has been demonstrated to be highly effective in preventing recurrences of atrial flutter. METHODS Seventy-one consecutive patients with paroxysmal or chronic AF, in whom flecainide infusion (2 mg/kg body weight, intravenously) determined the transformation of AF into common atrial flutter (positive response), were randomized to receive one of the following treatments: oral pharmacologic treatment with flecainide (group A, n = 23); the hybrid treatment (catheter ablation of the inferior vena cava-tricuspid annulus isthmus, plus oral flecainide) (group B, n = 24); or catheter ablation of the isthmus only (group C, n = 24). Thirty-seven patients with a negative response to flecainide, who chose to be submitted to the hybrid treatment, were selected as the control group (group D). RESULTS During a mean follow-up period of 24 +/- 7.2 months, the recurrences of AF and atrial flutter in group B (42%) were significantly lower than those in group A (78%, p < 0.001), group C (92%, p < 0.001) and group D (92%, p < 0.001). CONCLUSIONS The creation of a complete bi-directional conduction block at the inferior vena cava-tricuspid annulus isthmus, plus flecainide administration, reduces the recurrences of both AF and atrial flutter in patients with class IC atrial flutter. Moreover, the early response to flecainide is safe and reliable in identifying patients who may benefit from this therapy.

DETERMINANTS OF EFFICACY OF ATRIAL PACING IN PREVENTING ATRIAL FIBRILLATION RECURRENCES

Atrial Pacing in Atrial Fibrillation. Introduction: Several studies have shown that single or dual site atrial pacing is effective in reducing he frequency of recurrent atrial fibrillation (AF) in selected patients. However, it is still unclear what the best predictors are of long‐term efficacy of atrial pacing.

Long-Term Outcome of Right and Left Atrial Radiofrequency Ablation in Patients with Persistent Atrial Fibrillation

Objectives: To investigate the clinical outcome of right and left atrial radiofrequency ablation after the first 12 months in patients with drug‐refractory persistent atrial fibrillation (AF), and to identify predictors of long‐term success.

Feasibility of Pulmonary Vein Ostia Radiofrequency Ablation in Patients with Atrial Fibrillation: A Multicenter Study (CACAF Pilot Study)

STABILE, G., et al.: Feasibility of Pulmonary Vein Ostia Radiofrequency Ablation in Patients with Atrial Fibrillation: A Multicenter Study (CACAF Pilot Study) Radiofrequency (RF) catheter ablation has been proposed as a treatment of atrial fibrillation (AF). Several approaches have been reported and success rates have been dependent on procedural volume and operators experience. This is the first report of a multicenter study of RF ablation of AF. We treated 44 men and 25 women with paroxysmal (n = 40) or persistent (n = 29) , drug refractory AF. Circular pulmonary vein (PV) ostial lesions were deployed transseptally, during sinus rhythm(n = 42)or AF(n = 26), under three‐dimensional electroanatomic guidance. Cavo‐tricuspid isthmus ablation was performed in 27 (40%) patients. The mean procedure time was215 ± 76minutes (93–530), mean fluoroscopic exposure32 ± 14minutes (12–79), and mean number of RF pulses per patient56 ± 29(18–166). The mean numbers of separate PV ostia mapped and isolated per patient were3.9 ± 0.5, and3.8 ± 0.7, respectively. Major complications were observed in 3 (4%) patients, including pericardial effusion, transient ischemic attack, and tamponade. At 1‐month follow‐up, 21 of 68 (31%) patients had had AF recurrences, of whom 8 required electrical cardioversion. After the first month, over a mean period of9 ± 3(5–14) months, 57 (84%) patients remained free of atrial arrhythmias. RF ablation of AF by circumferential PV ostial ablation is feasible with a high short‐term success rate. While the procedure and fluoroscopic exposure duration were short, the incidence of major cardiac complications was not negligible. (PACE 2003; 26[Pt. II]:284–287)

Long-Term Performance of Coronary Sinus Leads Used for Cardiac Resynchronization Therapy

Background: Little is known regarding the long‐term performance of coronary sinus (CS) leads, which have an effect on the longevity of cardiac resynchronization therapy (CRT) systems.

Left ventricular functional recovery during cardiac resynchronization therapy: predictive role of asynchrony measured by strain rate analysis.

Cardiac resynchronization therapy (CRT) improves myocardial performance in patients with heart failure (HF) and left bundle‐branch block (LBBB). Tissue Doppler echocardiography (TDE) has already been used to guide the selection of candidates for CRT. The objective of this study is to correlate the effects of CRT on left ventricular (LV) systolic function with wall motion synchrony assessed by TDE. High frame TDE data were obtained in 15 patients (mean age = 68.9 years, 11 men) with LBBB (QRS = 163 ± 13 ms) to derive temporal intraventricular horizontal asynchrony indexes, expressed as the time difference at the onset of shortening between the septum and the lateral (S‐L) and antero‐inferior (A‐I) walls, and measure the amount of delayed longitudinal contraction (DLC) within the LV. All measurements were made at baseline, 24 hours after implantation, and at 1 year of follow‐up. The results show that LV ejection fraction (EF) increased from 25 ± 6.2% at baseline to 36.9 ± 7.9% at 1 year, and was strongly related to DLC, expressed either by time duration (DLCd, r =−0.51; P < 0.0001) or percent of the basal segments (%DLC, r =−0.50; P < 0.001). New York Heart Association functional class, which decreased from 3.6 ± 0.5 to 2.3 ± 0.8, was correlated with %DLC (r = 0.50) and DLCd (r = 0.48, P < 0.001). Weaker correlations were found between LVEF and S‐Li (r =−0.40) and between NYHA and S‐Li (r = 0.40). It is concluded that DLC was the best among intraventricular asynchrony indexes in predicting increases in LVEF after CRT. DLC may be useful to identify responders to CRT.