Antonio Simone - Academia.edu (original) (raw)

Papers by Antonio Simone

Research paper thumbnail of Instabilities in applying absorbing boundary conditions to high‐order seismic modeling algorithms

Research paper thumbnail of Acoustic comfort evaluation for hypermarket workers

Building and Environment, 2013

Abstract The paper presents the results of an on-site measurement procedure to assess acoustic co... more Abstract The paper presents the results of an on-site measurement procedure to assess acoustic comfort for hypermarket workers. The assessment is based on the collection of both objective measurements of environmental parameters as well as subjective ratings of acoustic comfort. The study was carried out in a hypermarket located in Southern Italy, in which four sub-spaces having similar acoustic characteristics were identified. Workers were asked to move to selected measuring points and fill in a questionnaire to rate their ...

Research paper thumbnail of The influence of clothing distribution and local discomfort on the assessment of global thermal comfort

Building and Environment, 2013

A field study was carried out in a hypermarket located in Southern Italy in order to evaluate the... more A field study was carried out in a hypermarket located in Southern Italy in order to evaluate the environmental comfort in large-scale retail trade buildings. Global and local thermal comfort conditions were studied by collecting exposure data and subjective responses of employees using both questionnaires and simultaneous physical measurements. In a few cases discrepancies appeared between subjective ratings and the corresponding PMV-index, suggesting that the latter could be unable to reliably estimate thermal comfort when clothing insulation is unevenly distributed on human body. Analysis of collected data confirmed this, with particular reference to female workers wearing skirts. In addition, such effects may be further emphasized by local thermal discomfort, which may finally influence global thermal perception. Analysis of the results showed that cold floor and radiant temperature asymmetry caused by warm ceiling played a major role in emphasizing the negative effects due to uneven clothing distribution, confirming that this particular combination of events may bias PMV model accuracy.

Research paper thumbnail of A measurement procedure to assess indoor environment quality for hypermarket workers

Building and Environment, 2012

The paper discusses the suitability of an on-site measurement procedure to assess indoor environm... more The paper discusses the suitability of an on-site measurement procedure to assess indoor environment quality for hypermarket workers. The method is based on the collection of both objective measurements of environmental parameters and subjective perceptions of Indoor Air Quality (IAQ) as well as thermal, acoustic, and visual comfort. Given the particular (and variable) indoor conditions observed in hypermarkets, a preliminary field study was carried out to verify the understanding of the questions and their effectiveness in describing subjects' perceptions and the suitably of the survey method to assess indoor environmental quality and comfort. A hypermarket located in Southern Italy was selected as a pilot study during which the exposure data and subjective responses of employees were acquired simultaneously through physical measurements and questionnaires. A major aspect that required to be verified was the use of fixed positions to avoid, as far as possible, any interference with workers' activities. In fact, workers were asked to move to the measuring point and fill in a questionnaire to rate their subjective perceptions. Measuring points were chosen to represent the typical conditions inside the hypermarket. However, in a few cases more extreme conditions (less representative of the average conditions) were selected in order to widen the range of the measured parameters and subjective reactions. Data collected at fixed point locations showed only minor (and predictable) biases due to expectation and to transition through different thermal environments, confirming that the proposed method is effective in this kind of environment and minimizes interference with working activities.

Research paper thumbnail of Left intraventricular myocardial deformation dyssynchrony identifies responders to cardiac resynchronization therapy in patients with heart failure

Aims We tested the hypothesis that dyssynchrony of left ventricular (LV) myocardial deformation e... more Aims We tested the hypothesis that dyssynchrony of left ventricular (LV) myocardial deformation evaluated by ultrasound can predict success of cardiac resynchronization therapy (CRT) in patients with heart failure (HF). Methods and results Thirty-seven patients with dilated cardiomyopathy, New York Heart Association class III-IV, LV ejection fraction (EF) 35%, QRS . 120 ms were studied before, at pre-discharge, and after 3 and 6 months of CRT. The M-mode peak septal-to-posterior wall motion and thickening delay (SPWMD and SPWTD, ms) and the standard deviation of the averaged time-to-peak strain (TPS-SD, ms) of 12 middle and basal LV segments obtained from the three standard apical views were calculated. Responders were defined at month 6 by 20% EF increase and/or 15% end-systolic volume (ESV) decrease with respect to baseline. Baseline SPWTD (not SPWMD) and TPS-SD differentiated responders from non-responders with good accuracy and reproducibility. A value 194 ms for SPWTD and 60 ms for TPS-SD was significantly associated with responder identification. Baseline dyssynchrony parameters correlated significantly with EF (r ¼ 0.53 for SPWTD and r ¼ 0.86 for TPS-SD) and ESV variations (r ¼ 20.42 for SPWTD and r ¼ 20.73 for TPS-SD).

Research paper thumbnail of Bifactorial Pricing Models: Light and Shadows in Correlation Role

Mathematical and Statistical Methods for Actuarial Sciences and Finance, 2014

ABSTRACT

Research paper thumbnail of An “Economical” Pricing Model for Hybrid Products

Rethinking Valuation and Pricing Models, 2013

Research paper thumbnail of Interest Rate Models for Pricing Derivatives: The Case of Cap Contracts

SSRN Electronic Journal, 2000

Research paper thumbnail of Energy minimizers for large ferromagnetic bodies

Archive for Rational Mechanics and Analysis, 1993

Research paper thumbnail of Energy minimizers for large ferromagnetic bodies

Archive for Rational Mechanics and Analysis, 1993

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

To evaluate the impact, on atrial fibrillation (AF) recurrences, of verapamil addition to a class... more 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 48 h. 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.

Research paper thumbnail of Role of transtelephonic electrocardiographic monitoring in detecting short-term arrhythmia recurrences after radiofrequency ablation in patients with atrial fibrillation

Journal of The American College of Cardiology, 2005

The aim of our study was to determine the incidence of asymptomatic recurrences of atrial fibrill... more The aim of our study was to determine the incidence of asymptomatic recurrences of atrial fibrillation (AF) by daily transtelephonic (TT) electrocardiographic (ECG) monitoring, as compared with standard ECG and 24-h Holter recording, in patients who underwent radiofrequency catheter ablation (RCA) of AF.The efficacy of RCA of AF is usually evaluated by means of patients’ symptoms.Seventy-two patients with paroxysmal (n = 37) or persistent (n = 35) drug-refractory AF underwent circumferential RCA of the pulmonary vein (PV) ostia. Left isthmus ablation was performed in 57 patients, and cavotricuspid isthmus ablation was done in 69 patients. Patients were scheduled to obtain an ECG and Holter recordings one and four months after ablation, as well as a daily TT ECG, from 30 to 120 days after ablation or in the event of symptoms.A total of 5,585 TT ECGs were obtained (mean 77.5 per patient). In 20 patients (27.8%), AF recurrences were recorded during TT ECG, whereas ECG and Holter monitoring revealed AF recurrences in 10 patients (13.9%, p = 0.001). Ten patients had at least one asymptomatic AF recurrence, and eight were completely asymptomatic. The ECG recorded in the event of symptoms always showed AF.Transtelephonic ECG is better than standard ECG and 24-h Holter recordings in evaluating AF relapses after RCA, thus decreasing the short-term success of ablation from 86% to 72%. The absence of symptoms should not be interpreted as absence of AF, as 50% of patients were asymptomatic during at least one AF episode.

Research paper thumbnail of Is Pulmonary Vein Isolation Necessary for Curing Atrial Fibrillation?

Background-Pulmonary veins (PVs) play a pivotal role in initiating and perpetuating atrial fibril... more Background-Pulmonary veins (PVs) play a pivotal role in initiating and perpetuating atrial fibrillation (AF). We investigated if PV electrical isolation from the left atrium is required for curing AF. Methods and Result-Fifty-one patients with paroxysmal or persistent AF underwent circumferential radiofrequency ablation of PV ostia performed with an anatomic approach. The end point of the ablation procedure was the recording of low peak-to-peak bipolar potentials (Ͻ0.1 mV) inside the lesions. Left atrium pacing was used to assess the conduction between the PVs and the left atrium. During a mean follow-up period of 16.6Ϯ3.9 months, 41 patients (80.4%) were free of atrial arrhythmias. When patients with and without AF recurrence were analyzed, no significant difference was observed in the mean number of PVs in which the ablation end point was reached 3.4Ϯ1.2 versus 3.7Ϯ0.87) and PVs isolated (1.5Ϯ1.4 versus 1.6Ϯ1). We noted that, although in 29 of 41 patients (71%) without AF recurrence, the ablation end point was reached in all PVs mapped, it was only possible to demonstrate the isolation of all PVs mapped in 2 patients. On the other hand, in 7 of 10 patients (70%) with AF recurrence, the ablation end point was reached in all PVs mapped, whereas one patient had all PVs isolated. Conclusions-Our findings show that with the use of a pure anatomic approach, it is possible to prevent AF in Ͼ80% of patients undergoing catheter ablation. Moreover, the isolation of PVs is not crucial for curing AF. (Circulation. 2003; 108:657-660.)

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

Journal of The American College of Cardiology, 1996

We compared the efficacy of two different mapping techniques in identifying the ablation site for... more 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.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.Forty-five patients with atrial tachycardia underwent radiofrequency catheter ablation. Mapping techniques included identification of earliest atrial activation and pace-mapping concordant sequence.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) ≥30 ms (p < 0.001) and pace-mapping concordant sequence (p = 0.01) were all significant predictors of outcome. An AP interval ≥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 specificity 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.An AP interval ≥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.

Research paper thumbnail of Pretreatment With Verapamil in Patients With Persistent or Chronic Atrial Fibrillation Who Underwent Electrical Cardioversion

To evaluate, in a prospective and randomized fashion, the efficacy of a pretreatment with verapam... more 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).

Research paper thumbnail of Catheter ablation treatment in patients with drug-refractory atrial fibrillation: a prospective, multi-centre, randomized, controlled study (Catheter Ablation For The Cure Of Atrial Fibrillation Study)

Aims We conducted a multi-centre, prospective, controlled, randomized trial to investigate the ad... more Aims We conducted a multi-centre, prospective, controlled, randomized trial to investigate the adjunctive role of ablation therapy to antiarrhythmic drug therapy in preventing atrial fibrillation (AF) relapses in patients with paroxysmal or persistent AF in whom antiarrhythmic drug therapy had already failed. Methods and results One hundred and thirty seven patients were randomized to ablation and antiarrhythmic drug therapy (ablation group) or antiarrhythmic drug therapy alone (control group). In the ablation group, patients underwent cavo-tricuspid and left inferior pulmonary vein (PV)-mitral isthmus ablation plus circumferential PV ablation. The primary end-point of the study was the absence of any recurrence of atrial arrhythmia lasting .30 s in the 1-year follow-up period, after 1-month blanking period. Three (4.4%) major complications were related to ablation: one patient had a stroke during left atrium ablation, another suffered transient phrenic paralysis, and the third had a pericardial effusion which required pericardiocentesis. After 12 months of follow-up, 63/69 (91.3%) control group patients had at least one AF recurrence, whereas 30/68 (44.1%) (P , 0.001) ablation group patients had atrial arrhythmia recurrence (four patients had atrial flutter, 26 patients AF). Conclusion Ablation therapy combined with antiarrhythmic drug therapy is superior to antiarrhythmic drug therapy alone in preventing atrial arrhythmia recurrences in patients with paroxysmal or persistent AF in whom antiarrhythmic drug therapy has already failed.

Research paper thumbnail of Feasibility and efficacy of electrical cardioversion after cardiac resynchronization implantation in patients with permanent atrial fibrillation

Journal of Interventional Cardiac Electrophysiology, 2012

Purpose Patients with permanent atrial fibrillation (AF) who undergo cardiac resynchronization th... more Purpose Patients with permanent atrial fibrillation (AF) who undergo cardiac resynchronization therapy (CRT) may spontaneously recover sinus rhythm during follow-up. We tested the feasibility and efficacy of electrical cardioversion attempted after 3 months of CRT in patients with permanent AF and measured the long-term maintenance of sinus rhythm.

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

Journal of The American College of Cardiology, 2001

OBJECTIVESWe tested the hypothesis that the response to flecainide infusion can identify patients... more OBJECTIVESWe 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.BACKGROUNDInfusion 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.METHODSSeventy-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).RESULTSDuring 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).CONCLUSIONSThe 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.

Research paper thumbnail of Determinants of Efficacy of Atrial Pacing in Preventing Atrial Fibrillation Recurrences

Journal of Cardiovascular Electrophysiology, 1999

CE).Jand the *Institulo Climco Humanitas. Rozzano; and the Departments of tCardioIogy and ^Geriat... more CE).Jand the *Institulo Climco Humanitas. Rozzano; and the Departments of tCardioIogy and ^Geriatrics, Federico lI"Universiiy of Naples.'Naples. Italyf Atrial Pacing in Atrial Fibrillation. Introduction: Several studies have shown that single or dual site atrial pacing is effective in reducing the frequency of recurrent atrial fibrillation (AF) in selected patients. However, it is still unclear what the besi predictors are of iong-lerm efficacy of atrial pacing.

Research paper thumbnail of Inappropriate Sinus Tachycardia After Radiofrequency Ablation of Para-Hisian Accessory Pathways

Journal of Cardiovascular Electrophysiology, 1997

Inappropriate Sinus Tachycardia After Catheter Ahlation. Introduction: Inappropriate sinus tachyc... more Inappropriate Sinus Tachycardia After Catheter Ahlation. Introduction: Inappropriate sinus tachycardia (IST) has been observed following radiofrequency ablation (RFA) of the AV nodal fast patbway. This study was aimed to prospectively analyze tbe incidence and clinical signiticance of IST following RFA of para-Hisian accessory patbways (APs).

Research paper thumbnail of Instabilities in applying absorbing boundary conditions to high‐order seismic modeling algorithms

Research paper thumbnail of Acoustic comfort evaluation for hypermarket workers

Building and Environment, 2013

Abstract The paper presents the results of an on-site measurement procedure to assess acoustic co... more Abstract The paper presents the results of an on-site measurement procedure to assess acoustic comfort for hypermarket workers. The assessment is based on the collection of both objective measurements of environmental parameters as well as subjective ratings of acoustic comfort. The study was carried out in a hypermarket located in Southern Italy, in which four sub-spaces having similar acoustic characteristics were identified. Workers were asked to move to selected measuring points and fill in a questionnaire to rate their ...

Research paper thumbnail of The influence of clothing distribution and local discomfort on the assessment of global thermal comfort

Building and Environment, 2013

A field study was carried out in a hypermarket located in Southern Italy in order to evaluate the... more A field study was carried out in a hypermarket located in Southern Italy in order to evaluate the environmental comfort in large-scale retail trade buildings. Global and local thermal comfort conditions were studied by collecting exposure data and subjective responses of employees using both questionnaires and simultaneous physical measurements. In a few cases discrepancies appeared between subjective ratings and the corresponding PMV-index, suggesting that the latter could be unable to reliably estimate thermal comfort when clothing insulation is unevenly distributed on human body. Analysis of collected data confirmed this, with particular reference to female workers wearing skirts. In addition, such effects may be further emphasized by local thermal discomfort, which may finally influence global thermal perception. Analysis of the results showed that cold floor and radiant temperature asymmetry caused by warm ceiling played a major role in emphasizing the negative effects due to uneven clothing distribution, confirming that this particular combination of events may bias PMV model accuracy.

Research paper thumbnail of A measurement procedure to assess indoor environment quality for hypermarket workers

Building and Environment, 2012

The paper discusses the suitability of an on-site measurement procedure to assess indoor environm... more The paper discusses the suitability of an on-site measurement procedure to assess indoor environment quality for hypermarket workers. The method is based on the collection of both objective measurements of environmental parameters and subjective perceptions of Indoor Air Quality (IAQ) as well as thermal, acoustic, and visual comfort. Given the particular (and variable) indoor conditions observed in hypermarkets, a preliminary field study was carried out to verify the understanding of the questions and their effectiveness in describing subjects' perceptions and the suitably of the survey method to assess indoor environmental quality and comfort. A hypermarket located in Southern Italy was selected as a pilot study during which the exposure data and subjective responses of employees were acquired simultaneously through physical measurements and questionnaires. A major aspect that required to be verified was the use of fixed positions to avoid, as far as possible, any interference with workers' activities. In fact, workers were asked to move to the measuring point and fill in a questionnaire to rate their subjective perceptions. Measuring points were chosen to represent the typical conditions inside the hypermarket. However, in a few cases more extreme conditions (less representative of the average conditions) were selected in order to widen the range of the measured parameters and subjective reactions. Data collected at fixed point locations showed only minor (and predictable) biases due to expectation and to transition through different thermal environments, confirming that the proposed method is effective in this kind of environment and minimizes interference with working activities.

Research paper thumbnail of Left intraventricular myocardial deformation dyssynchrony identifies responders to cardiac resynchronization therapy in patients with heart failure

Aims We tested the hypothesis that dyssynchrony of left ventricular (LV) myocardial deformation e... more Aims We tested the hypothesis that dyssynchrony of left ventricular (LV) myocardial deformation evaluated by ultrasound can predict success of cardiac resynchronization therapy (CRT) in patients with heart failure (HF). Methods and results Thirty-seven patients with dilated cardiomyopathy, New York Heart Association class III-IV, LV ejection fraction (EF) 35%, QRS . 120 ms were studied before, at pre-discharge, and after 3 and 6 months of CRT. The M-mode peak septal-to-posterior wall motion and thickening delay (SPWMD and SPWTD, ms) and the standard deviation of the averaged time-to-peak strain (TPS-SD, ms) of 12 middle and basal LV segments obtained from the three standard apical views were calculated. Responders were defined at month 6 by 20% EF increase and/or 15% end-systolic volume (ESV) decrease with respect to baseline. Baseline SPWTD (not SPWMD) and TPS-SD differentiated responders from non-responders with good accuracy and reproducibility. A value 194 ms for SPWTD and 60 ms for TPS-SD was significantly associated with responder identification. Baseline dyssynchrony parameters correlated significantly with EF (r ¼ 0.53 for SPWTD and r ¼ 0.86 for TPS-SD) and ESV variations (r ¼ 20.42 for SPWTD and r ¼ 20.73 for TPS-SD).

Research paper thumbnail of Bifactorial Pricing Models: Light and Shadows in Correlation Role

Mathematical and Statistical Methods for Actuarial Sciences and Finance, 2014

ABSTRACT

Research paper thumbnail of An “Economical” Pricing Model for Hybrid Products

Rethinking Valuation and Pricing Models, 2013

Research paper thumbnail of Interest Rate Models for Pricing Derivatives: The Case of Cap Contracts

SSRN Electronic Journal, 2000

Research paper thumbnail of Energy minimizers for large ferromagnetic bodies

Archive for Rational Mechanics and Analysis, 1993

Research paper thumbnail of Energy minimizers for large ferromagnetic bodies

Archive for Rational Mechanics and Analysis, 1993

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

To evaluate the impact, on atrial fibrillation (AF) recurrences, of verapamil addition to a class... more 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 48 h. 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.

Research paper thumbnail of Role of transtelephonic electrocardiographic monitoring in detecting short-term arrhythmia recurrences after radiofrequency ablation in patients with atrial fibrillation

Journal of The American College of Cardiology, 2005

The aim of our study was to determine the incidence of asymptomatic recurrences of atrial fibrill... more The aim of our study was to determine the incidence of asymptomatic recurrences of atrial fibrillation (AF) by daily transtelephonic (TT) electrocardiographic (ECG) monitoring, as compared with standard ECG and 24-h Holter recording, in patients who underwent radiofrequency catheter ablation (RCA) of AF.The efficacy of RCA of AF is usually evaluated by means of patients’ symptoms.Seventy-two patients with paroxysmal (n = 37) or persistent (n = 35) drug-refractory AF underwent circumferential RCA of the pulmonary vein (PV) ostia. Left isthmus ablation was performed in 57 patients, and cavotricuspid isthmus ablation was done in 69 patients. Patients were scheduled to obtain an ECG and Holter recordings one and four months after ablation, as well as a daily TT ECG, from 30 to 120 days after ablation or in the event of symptoms.A total of 5,585 TT ECGs were obtained (mean 77.5 per patient). In 20 patients (27.8%), AF recurrences were recorded during TT ECG, whereas ECG and Holter monitoring revealed AF recurrences in 10 patients (13.9%, p = 0.001). Ten patients had at least one asymptomatic AF recurrence, and eight were completely asymptomatic. The ECG recorded in the event of symptoms always showed AF.Transtelephonic ECG is better than standard ECG and 24-h Holter recordings in evaluating AF relapses after RCA, thus decreasing the short-term success of ablation from 86% to 72%. The absence of symptoms should not be interpreted as absence of AF, as 50% of patients were asymptomatic during at least one AF episode.

Research paper thumbnail of Is Pulmonary Vein Isolation Necessary for Curing Atrial Fibrillation?

Background-Pulmonary veins (PVs) play a pivotal role in initiating and perpetuating atrial fibril... more Background-Pulmonary veins (PVs) play a pivotal role in initiating and perpetuating atrial fibrillation (AF). We investigated if PV electrical isolation from the left atrium is required for curing AF. Methods and Result-Fifty-one patients with paroxysmal or persistent AF underwent circumferential radiofrequency ablation of PV ostia performed with an anatomic approach. The end point of the ablation procedure was the recording of low peak-to-peak bipolar potentials (Ͻ0.1 mV) inside the lesions. Left atrium pacing was used to assess the conduction between the PVs and the left atrium. During a mean follow-up period of 16.6Ϯ3.9 months, 41 patients (80.4%) were free of atrial arrhythmias. When patients with and without AF recurrence were analyzed, no significant difference was observed in the mean number of PVs in which the ablation end point was reached 3.4Ϯ1.2 versus 3.7Ϯ0.87) and PVs isolated (1.5Ϯ1.4 versus 1.6Ϯ1). We noted that, although in 29 of 41 patients (71%) without AF recurrence, the ablation end point was reached in all PVs mapped, it was only possible to demonstrate the isolation of all PVs mapped in 2 patients. On the other hand, in 7 of 10 patients (70%) with AF recurrence, the ablation end point was reached in all PVs mapped, whereas one patient had all PVs isolated. Conclusions-Our findings show that with the use of a pure anatomic approach, it is possible to prevent AF in Ͼ80% of patients undergoing catheter ablation. Moreover, the isolation of PVs is not crucial for curing AF. (Circulation. 2003; 108:657-660.)

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

Journal of The American College of Cardiology, 1996

We compared the efficacy of two different mapping techniques in identifying the ablation site for... more 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.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.Forty-five patients with atrial tachycardia underwent radiofrequency catheter ablation. Mapping techniques included identification of earliest atrial activation and pace-mapping concordant sequence.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) ≥30 ms (p < 0.001) and pace-mapping concordant sequence (p = 0.01) were all significant predictors of outcome. An AP interval ≥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 specificity 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.An AP interval ≥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.

Research paper thumbnail of Pretreatment With Verapamil in Patients With Persistent or Chronic Atrial Fibrillation Who Underwent Electrical Cardioversion

To evaluate, in a prospective and randomized fashion, the efficacy of a pretreatment with verapam... more 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).

Research paper thumbnail of Catheter ablation treatment in patients with drug-refractory atrial fibrillation: a prospective, multi-centre, randomized, controlled study (Catheter Ablation For The Cure Of Atrial Fibrillation Study)

Aims We conducted a multi-centre, prospective, controlled, randomized trial to investigate the ad... more Aims We conducted a multi-centre, prospective, controlled, randomized trial to investigate the adjunctive role of ablation therapy to antiarrhythmic drug therapy in preventing atrial fibrillation (AF) relapses in patients with paroxysmal or persistent AF in whom antiarrhythmic drug therapy had already failed. Methods and results One hundred and thirty seven patients were randomized to ablation and antiarrhythmic drug therapy (ablation group) or antiarrhythmic drug therapy alone (control group). In the ablation group, patients underwent cavo-tricuspid and left inferior pulmonary vein (PV)-mitral isthmus ablation plus circumferential PV ablation. The primary end-point of the study was the absence of any recurrence of atrial arrhythmia lasting .30 s in the 1-year follow-up period, after 1-month blanking period. Three (4.4%) major complications were related to ablation: one patient had a stroke during left atrium ablation, another suffered transient phrenic paralysis, and the third had a pericardial effusion which required pericardiocentesis. After 12 months of follow-up, 63/69 (91.3%) control group patients had at least one AF recurrence, whereas 30/68 (44.1%) (P , 0.001) ablation group patients had atrial arrhythmia recurrence (four patients had atrial flutter, 26 patients AF). Conclusion Ablation therapy combined with antiarrhythmic drug therapy is superior to antiarrhythmic drug therapy alone in preventing atrial arrhythmia recurrences in patients with paroxysmal or persistent AF in whom antiarrhythmic drug therapy has already failed.

Research paper thumbnail of Feasibility and efficacy of electrical cardioversion after cardiac resynchronization implantation in patients with permanent atrial fibrillation

Journal of Interventional Cardiac Electrophysiology, 2012

Purpose Patients with permanent atrial fibrillation (AF) who undergo cardiac resynchronization th... more Purpose Patients with permanent atrial fibrillation (AF) who undergo cardiac resynchronization therapy (CRT) may spontaneously recover sinus rhythm during follow-up. We tested the feasibility and efficacy of electrical cardioversion attempted after 3 months of CRT in patients with permanent AF and measured the long-term maintenance of sinus rhythm.

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

Journal of The American College of Cardiology, 2001

OBJECTIVESWe tested the hypothesis that the response to flecainide infusion can identify patients... more OBJECTIVESWe 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.BACKGROUNDInfusion 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.METHODSSeventy-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).RESULTSDuring 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).CONCLUSIONSThe 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.

Research paper thumbnail of Determinants of Efficacy of Atrial Pacing in Preventing Atrial Fibrillation Recurrences

Journal of Cardiovascular Electrophysiology, 1999

CE).Jand the *Institulo Climco Humanitas. Rozzano; and the Departments of tCardioIogy and ^Geriat... more CE).Jand the *Institulo Climco Humanitas. Rozzano; and the Departments of tCardioIogy and ^Geriatrics, Federico lI"Universiiy of Naples.'Naples. Italyf Atrial Pacing in Atrial Fibrillation. Introduction: Several studies have shown that single or dual site atrial pacing is effective in reducing the frequency of recurrent atrial fibrillation (AF) in selected patients. However, it is still unclear what the besi predictors are of iong-lerm efficacy of atrial pacing.

Research paper thumbnail of Inappropriate Sinus Tachycardia After Radiofrequency Ablation of Para-Hisian Accessory Pathways

Journal of Cardiovascular Electrophysiology, 1997

Inappropriate Sinus Tachycardia After Catheter Ahlation. Introduction: Inappropriate sinus tachyc... more Inappropriate Sinus Tachycardia After Catheter Ahlation. Introduction: Inappropriate sinus tachycardia (IST) has been observed following radiofrequency ablation (RFA) of the AV nodal fast patbway. This study was aimed to prospectively analyze tbe incidence and clinical signiticance of IST following RFA of para-Hisian accessory patbways (APs).