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R Cappato

Publications and source records attributed to R Cappato.

At least 19 recordsLinked to original sources
PubMed2002

Ventricular mapping during atrial and ventricular pacing. Relationship of multipotential electrograms to ventricular tachycardia reentry circuits after myocardial infarction.

AIMS: Conduction through separated myocyte bundles causes multipotential electrograms and reentrant ventricular tachycardia. We hypothesized that without initiating tachycardia, the reentry region could be detected by analysing the change in multipotential electrograms during two different activation sequences. METHODS AND RESULTS: During catheter mapping and ablation in 16 patients with ventricular tachycardia late after infarction ventricular electrograms were recorded from 1072 sites during atrial and right ventricular paced ventricular activation. Multipotential electrograms were present during both activation sequences at 285 (27%) sites, during atrial pacing only at 159 (15%) sites and during right ventricular pacing only at 152 (14%) sites. Sites with multipotential electrograms during both activation sequences were more often related to a ventricular tachycardia circuit isthmus (43%) as compared to sites where such electrograms were present during one activation sequence (20%). Multipotential electrograms with >2 low amplitude deflections and a >100 ms difference in duration between the two activation sequences were infrequent but highly predictive of the reentry circuit. CONCLUSION: Regions with fixed multipotentials consistent with conduction block might be useful guides for ablation approaches that target large regions of the infarct, but are not sufficiently specific to be the sole guide for focal ablation approaches.

Aged↗
PubMed2002

Task Force on Sudden Cardiac Death, European Society of Cardiology.

The European Society of Cardiology has convened a Task Force on Sudden Cardiac Death in order to provide a comprehensive, educational document on this important topic. The main document has been published in the European Heart Journal in August 2001. The Task Force has now summarized the most important clinical issues on sudden cardiac death and provided tables with recommendations for risk stratification and for prophylaxis of sudden cardiac death. The present recommendations are specifically intended to encourage the development and revision of national guidelines on prevention of sudden cardiac death. The common challenge for cardiologists, physicians of other medical specialties and health professionals throughout Europe is to realize the potential for sudden cardiac death prevention and to contribute to public health efforts to reduce its burden.

Advisory Committees↗
PubMed2001

Efficacy and safety of out-of-hospital self-administered single-dose oral drug treatment in the management of infrequent, well-tolerated paroxysmal supraventricular tachycardia.

OBJECTIVES: We tested the efficacy of two drug treatments, flecainide (F) and the combination ofdiltiazem and propranolol (D/P), administered as a single oral dose for termination of the arrhythmic episodes. BACKGROUND: Both prophylactic drug therapy and catheter ablation are questionable as first-line treatments in patients with infrequent and well-tolerated episodes of paroxysmal supraventricular tachycardia (SVT). METHODS: Among 42 eligible patients (13% of all screened for SVT) with infrequent (< or =5/year), well-tolerated and long-lasting episodes, 37 were enrolled and 33 had SVT inducible during electrophysiological study. In the latter, three treatments (placebo, F, and D/P) were administered in a random order 5 min after SVT induction on three different days. RESULTS: Conversion to sinus rhythm occurred within 2 h in 52%, 61%, and 94% of patients on placebo, F and D/P, respectively (p < 0.001). The conversion time was shorter after D/P (32 +/- 22 min) than after placebo (77 +/- 42 min, p < 0.001) or F (74 +/- 37 min, p < 0.001). Four patients (1 placebo, 1 D/P, and 2 F) had hypotension and four (3 D/P and 1 F) a sinus rate <50 beats/min following SVT interruption. Patients were discharged on a single oral dose of the most effective drug treatment (F or D/P) at time of acute testing. Twenty-six patients were discharged on D/P and five on F. During 17 +/- 12 months follow-up, the treatment was successful in 81% of D/P patients and in 80% of F patients, as all the arrhythmic episodes were interrupted out-of-hospital within 2 h. In the remaining patients, a failure occurred during one or more episodes because of drug ineffectiveness or drug unavailability. One patient had syncope after D/P ingestion. During follow-up, the percentage of patients calling for emergency room assistance was significantly reduced as compared to the year before enrollment (9% vs. 100%, p < 0.0001). CONCLUSIONS: The episodic treatment with oral D/P and F, as assessed during acute testing, appears effective in the management of selected patients with SVT. This therapeutic strategy minimizes the need for emergency room admissions during tachycardia recurrences.

Administration, Oral↗
PubMed2000

Randomized comparison of antiarrhythmic drug therapy with implantable defibrillators in patients resuscitated from cardiac arrest : the Cardiac Arrest Study Hamburg (CASH).

BACKGROUND: We conducted a prospective, multicenter, randomized comparison of implantable cardioverter-defibrillator (ICD) versus antiarrhythmic drug therapy in survivors of cardiac arrest secondary to documented ventricular arrhythmias. METHODS AND RESULTS: From 1987, eligible patients were randomized to an ICD, amiodarone, propafenone, or metoprolol (ICD versus antiarrhythmic agents randomization ratio 1:3). Assignment to propafenone was discontinued in March 1992, after an interim analysis conducted in 58 patients showed a 61% higher all-cause mortality rate than in 61 ICD patients during a follow-up of 11.3 months. The study continued to recruit 288 patients in the remaining 3 study groups; of these, 99 were assigned to ICDs, 92 to amiodarone, and 97 to metoprolol. The primary end point was all-cause mortality. The study was terminated in March 1998, when all patients had concluded a minimum 2-year follow-up. Over a mean follow-up of 57+/-34 months, the crude death rates were 36.4% (95% CI 26.9% to 46.6%) in the ICD and 44.4% (95% CI 37.2% to 51.8%) in the amiodarone/metoprolol arm. Overall survival was higher, though not significantly, in patients assigned to ICD than in those assigned to drug therapy (1-sided P=0.081, hazard ratio 0.766, [97.5% CI upper bound 1.112]). In ICD patients, the percent reductions in all-cause mortality were 41.9%, 39.3%, 28. 4%, 27.7%, 22.8%, 11.4%, 9.1%, 10.6%, and 24.7% at years 1 to 9 of follow-up. CONCLUSIONS: During long-term follow-up of cardiac arrest survivors, therapy with an ICD is associated with a 23% (nonsignificant) reduction of all-cause mortality rates when compared with treatment with amiodarone/metoprolol. The benefit of ICD therapy is more evident during the first 5 years after the index event.

Aged↗
PubMed2000

Significance of newly acquired negative T waves after interruption of paroxysmal reentrant supraventricular tachycardia with narrow QRS complex.

Sixty-three patients with paroxysmal supraventricular tachycardia were studied and 25 patients (39%) showed newly acquired negative T waves after tachycardia termination. Silent coronary artery disease could not be found in about 90% of these patients; moreover, age, sex, organic heart disease, and tachycardia duration and rate did not predict the appearance of negative T waves.

Electrocardiography↗
PubMed2000

Meta-analysis of the implantable cardioverter defibrillator secondary prevention trials. AVID, CASH and CIDS studies. Antiarrhythmics vs Implantable Defibrillator study. Cardiac Arrest Study Hamburg . Canadian Implantable Defibrillator Study.

AIMS: Three randomized trials of implantable cardioverter defibrillator (ICD) therapy vs medical treatment for the prevention of death in survivors of ventricular fibrillation or sustained ventricular tachycardia have been reported with what might appear to be different results. The present analysis was performed to obtain the most precise estimate of the efficacy of the ICD, compared to amiodarone, for prolonging survival in patients with malignant ventricular arrhythmia. METHODS AND RESULTS: Individual patient data from the Antiarrhythmics vs Implantable Defibrillator (AVID) study, the Cardiac Arrest Study Hamburg (CASH) and the Canadian Implantable Defibrillator Study (CIDS) were merged into a master database according to a pre-specified protocol. Proportional hazard modelling of individual patient data was used to estimate hazard ratios and to investigate subgroup interactions. Fixed effect meta-analysis techniques were also used to evaluate treatment effects and to assess heterogeneity across studies. The classic fixed effects meta-analysis showed that the estimates of ICD benefit from the three studies were consistent with each other (P heterogeneity=0.306). It also showed a significant reduction in death from any cause with the ICD; with a summary hazard ratio (ICD:amiodarone) of 0.72 (95% confidence interval 0.60, 0.87;P=0.0006). For the outcome of arrhythmic death, the hazard ratio was 0.50 (95% confidence interval 0.37, 0.67;P<0.0001). Survival was extended by a mean of 4.4 months by the ICD over a follow-up period of 6 years. Patients with left ventricular ejection fraction < or = 35% derived significantly more benefit from ICD therapy than those with better preserved left ventricular function. Patients treated before the availability of non-thoracotomy ICD implants derived significantly less benefit from ICD therapy than those treated in the non-thoracotomy era. CONCLUSION: Results from the three trials of the ICD vs amiodarone are consistent with each other. There is a 28% reduction in the relative risk of death with the ICD that is due almost entirely to a 50% reduction in arrhythmic death.

Amiodarone↗
PubMed2000

Catheter ablation in the year 2000.

After its introduction in 1987, radiofrequency catheter ablation became established as a safe and effective therapy for the cure of many cardiac arrhythmias in people. The possibility of assessing the relationship between the anatomical target and the electrophysiologic changes produced by radiofrequency pulse delivery has also provided significant improvement in the physician's knowledge of the pathophysiology of the underlying rhythm disturbance. Nowadays, using this therapy, success rates well above 90% with recurrence rates lower than 5% are expected after treatment of most regular supraventricular arrhythmias. As catheter ablation techniques develop, success rates in the range of those obtained for regular supraventricular arrhythmias are expected in the future in the treatment of regular ventricular and irregular supraventricular arrhythmias.

Catheter Ablation↗
PubMed1999

Modification of the substrate for maintenance of idiopathic human atrial fibrillation: efficacy of radiofrequency ablation using nonfluoroscopic catheter guidance.

BACKGROUND: Catheter ablative techniques to modify the substrate to maintain atrial fibrillation (AF) require the creation of continuous radiofrequency current-induced ablation lines. This study was designed to assess the efficacy and safety of nonfluoroscopic mapping in this setting. METHODS AND RESULTS: A total of 45 consecutive patients with idiopathic AF were studied. The first 13 underwent ablation confined to the left atrium by creating a circular line isolating the pulmonary vein ostia and a second line connecting the former with the mitral annulus. Subsequently, 12 of these patients underwent a procedure confined to the right atrium (RA), where attempts were made to create an isthmus line between the inferior vena cava and the tricuspid annulus, an anterior line connecting the tricuspid annulus with the superior vena cava, and an intercaval line between the ostia of the inferior and superior venae cavae. In the last 32 patients, only the RA approach was performed. Technical difficulties prevented the creation of the intended left atrial line pattern: all patients experienced recurrences. A 100% recurrence rate was also observed after subsequent RA ablation, despite creation of a complete line pattern in 4 of 12 patients. Of the final 32 patients, AF recurred in 94%; a complete ablation line pattern had been achieved in 18 patients (56%), 16 of whom had recurrences. CONCLUSIONS: The electroanatomically-guided creation of extended radiofrequency current lesions is technically feasible only in the RA. However, procedural success in the RA does not suppress recurrences of AF in the majority of patients.

Atrial Fibrillation↗
PubMed1999

Catheter ablation of paroxysmal atrial fibrillation using a 3D mapping system.

BACKGROUND: We treated paroxysmal recurrent atrial fibrillation (AF) with radiofrequency (RF) catheter ablation by creating long linear lesions in the atria. To achieve line continuity, a 3D electroanatomic nonfluoroscopic mapping system was used. METHODS AND RESULTS: In 27 patients with recurrent AF, a catheter incorporating a passive magnetic field sensor was navigated in both atria to construct a 3D activation map. RF energy was delivered to create continuous linear lesions: 3 lines (intercaval, isthmic, and anteroseptal) in the right atrium and a long line encircling the pulmonary veins in the left atrium. After RF application, the atria were remapped to validate completeness of the block lines, demonstrated by late activation of the areas circumscribed by the lines. The mean procedure duration was 312+/-103 minutes (range, 187 to 495), with mean fluoroscopy time of 107+/-44 minutes (range, 32 to 185 minutes). No acute complications occurred, but 1 patient experienced early prolonged sinus pauses and received a pacemaker. During the first day, 17 patients (63%) had AF episodes, but at discharge, 25 patients were in sinus rhythm. After a follow-up of 6. 0 to 15.3 months (average, 10.5+/-3.0 months), 16 patients are asymptomatic, 3 have an almost complete disappearance of symptoms, 1 patient is improved, and 7 patients have their AF attacks unchanged. CONCLUSIONS: Paroxysmal recurrent drug-refractory AF can be treated by RF catheter ablation. Creation of long continuous linear lesions necessary to compartmentalize the atria is facilitated by a nonfluoroscopic electroanatomic mapping system.

Adult↗
PubMed1999

Secondary prevention of sudden death: the Dutch Study, the Antiarrhythmics Versus Implantable Defibrillator Trial, the Cardiac Arrest Study Hamburg, and the Canadian Implantable Defibrillator Study.

Although indisputably effective in the prevention of sudden death, use of implantable cardioverter defibrillator (ICD) therapy may not necessarily affect all-cause mortality, as most patients at risk also present with severely depressed left ventricular dysfunction. Correction of the sudden death risk in these patients creates a new clinical condition in need of a careful assessment. Should all-cause mortality be affected by the expected reduction in sudden death rate associated with ICD therapy, issues of critical importance, such as the time extent of life prolongation and the associated quality of life, still remain to established. To investigate the potential benefit of ICD therapy compared with antiarrhythmic drug treatment, 4 prospective studies--the Dutch trial, the Antiarrhythmics Versus Implantable Defibrillators (AVID) study, the Cardiac Arrest Study Hamburg (CASH), and the Canadian Implantable Defibrillator Study (CIDS)--have been conducted in which patients with documented sustained ventricular arrhythmia were randomized to 1 of these 2 treatment strategies. The enrollment criteria differed in these 4 studies: (1) in the Dutch trial, they included cardiac arrest secondary to a ventricular arrhythmia, old (> 4 weeks) myocardial infarction, and inducible ventricular arrhythmia; (2) in AVID and CIDS, ventricular fibrillation or poorly tolerated ventricular tachycardia; and (3) in CASH, cardiac arrest secondary to a ventricular arrhythmia regardless of the underlying disease. With regard to the antiarrhythmic drugs, the Dutch trial tested class I and III agents, whereas AVID and CIDS compared ICD therapy with class III agents (mostly amiodarone). In CASH, 3 drug subgroups were investigated: propafenone, amiodarone, and metoprolol. All trials used all-cause mortality as the primary endpoint. Data from these trials provide support for ICD as a therapy superior to antiarrhythmic drugs in prolonging survival in patients meeting the entry criteria. This review briefly summarizes the methods, results, limitations, and clinical implications of these 4 studies.

Anti-Arrhythmia Agents↗
PubMed1999

Which strategy is "best" after myocardial infarction? The Beta-blocker Strategy plus Implantable Cardioverter Defibrillator Trial: rationale and study design.

The Beta-blocker Strategy plus Implantable Cardioverter Defibrillator (BEST-ICD) Trial is a multicenter prospective randomized trial that started in June 1998, in 95 centers in Italy and Germany. The trial will test the hypothesis whether, in high-risk post myocardial infarction (MI) patients already treated with beta blockers, electrophysiologic study (EPS)-guided therapy (including the prophylactic implantation of implantable cardioverter defibrillator [ICD] in inducible patients) will improve survival compared with conventional therapy. Patients eligible for the study are survivors of recent MI (> or = 5 and < or = 21 days), aged < or = 80 years, with left ventricular ejection fraction < or = 35% and > or = 1 of the following additional risk factors: (1) ventricular premature beats > or = 10/hour; (2) decreased heart rate variability (standard deviation of unusual RR intervals < 70 msec); and (3) presence of ventricular late potentials. Furthermore, all enrolled patients must be able to tolerate at least 25 mg of metoprolol per day. These patients constitute about 9% of all patients with recent MI and are expected to have a 2-year all-cause mortality > 25% of which 50% is anticipated to be from sudden death. The main criteria of exclusion from the study are (1) a history of sustained ventricular arrhythmia; (2) documentation of nonsustained ventricular tachycardia during the screening phase; and (3) the need for myocardial revascularization and contraindications or intolerance to beta-blocker therapy. Eligible patients will be randomized to 2 different therapeutic strategies: conventional strategy or EPS/ICD strategy. Patients allocated to the EPS/ICD strategy will undergo further risk stratification, and electrophysiologically inducible patients (approximately 35%) will receive prophylactic ICDs, in addition to the conventional therapy, whereas noninducible patients will be only conventionally treated. The primary endpoint of the study will be death from all causes. By hypothesizing a 30% reduction in the 2-year mortality (from 20% to 14%) in the EPS/ICD group compared with conventionally treated patients, 1,200 patients will have to be included. A triangular, 2-sided sequential design with preset boundaries, for a 5% significance level and 90% power to detect a reduction in 2-year mortality from 20% to 14%, will be used to permit early termination of the trial if the strategy is found to be efficacious, no difference, or inefficacious.

Adrenergic beta-Antagonists↗
PubMed1999

Prospective evaluation of the coronary sinus anatomy in patients undergoing electrophysiologic study.

BACKGROUND: Previous retrospective studies could find a predominant incidence of coronary sinus (CS) anomalies in patients with accessory pathways and a characteristic anatomy of the CS ostium in patients with atrioventricular nodal reentrant tachycardias (AVNRT). HYPOTHESIS: In the present prospective study, CS angiograms were prospectively performed to analyze the incidence of CS anomalies and to measure the diameters of the CS ostium. METHODS: The study included patients referred for electrophysiologic study and catheter ablation of various tachyarrhythmias. The anatomy of the CS and its side branches was visualized [left anterior oblique (LAO) 30 degrees, right anterior oblique (RAO) 30 degrees] by retrograde angiography in 204 consecutive patients (82 women, 122 men, age 45 +/- 15 years); of these, 120 presented with 123 accessory pathways (45 left-sided, 33 right-sided, 45 septal). The diagnosis in the remaining patients was atrioventricular nodal reentrant tachycardia in 43 cases, atrial tachycardia or atrial fibrillation in 12, and ventricular tachycardia in 15. In 14 patients, the indication for the electrophysiologic study was an unexplained syncope. The CS angiogram was evaluated for anomalies and the size of the CS ostium was manually measured in both projections. RESULTS: Anomalies of the CS defined as diverticula, persistent left superior vena cava, or enlarged CS ostia were found in 18 patients (9%). Of those, CS diverticula were found in nine patients, all with a posteroseptal or left posterior manifest accessory pathway, which was abolished within the neck of the diverticulum in seven patients and at the posteroseptal tricuspid annulus in two patients. Persistence of the left superior vena cava was found in five patients, four had atrioventricular reentrant tachycardia secondary to five accessory pathways (left free wall in four, right midseptal in one), and one patient had atrioventricular nodal reentrant tachycardia (AVNRT). Enlargement of the CS ostium of > 25 mm width was detected in nine patients (5%), of whom four had AVNRT. However, the width of the CS ostium generally did not differ significantly between patients with AVNRT (LAO: 14.4 +/- 5.6; RAO 9.3 +/- 2.4 mm) compared with the control group (LAO 13.4 +/- 4.1; 8.2 +/- 1.9 mm). CONCLUSIONS: Anomalies of the CS as diverticula, persistent superior vena cava, or enlargement of the CS ostium are predominantly found in patients with accessory pathway-related tachycardias. Diverticula of the proximal CS were found in 7% of patients with accessory pathways; in these cases, ablation succeeded mostly by radiofrequency (RF) current delivery in the neck of the diverticulum. Enlargement of the CS ostium was more often seen in patients with AVNRT than in all other patients. However, in general the measurements of the coronary sinus ostium did not significantly differ in patients with AVNRT compared with the control group.

Adult↗