Paolo Di Donna

Long-Term Clinical Results of 2 Different Ablation Strategies in Patients With Paroxysmal and Persistent Atrial Fibrillation

Background—Data regarding the long-term efficacy of atrial fibrillation (AF) ablation are still lacking. Methods and Results—Two hundred four consecutive patients symptomatic for paroxysmal or persistent/permanent AF were randomly assigned to 2 different ablation schemes: pulmonary vein isolation (PVI) and PVI plus left linear lesions (LL). Primary end point was to assess the maintenance of sinus rhythm (SR) after procedures 1 and 2 in the absence of antiarrhythmic drugs in a long-term follow-up of at least 3 years. Paroxysmal AF—With a single procedure at 12-month follow-up, 46% of patients treated with PVI maintained SR, whereas at 3-year follow-up, 29% were in SR; using the “PVI plus LL” at the 12-month follow-up, 57% of patients were in SR, whereas at the 3-year follow-up, 53% remained in SR. After a second procedure, the long-term overall success rate without antiarrhythmic drugs was 62% with PVI and 85% with PVI plus LL. Persistent/Permanent AF—With a single procedure at the 12-month follow-up, 27% of patients treated with PVI were in SR, whereas at the 3-year follow-up, 19% maintained SR; using the PVI plus LL with a single procedure at the 12-month follow-up 45% of patients were in SR, whereas at the 3-year follow-up, 41% remained in SR. After a second procedure, the long-term overall success rate without antiarrhythmic drugs was 39% with PVI and 75% with PVI plus LL. Conclusions—A long-term follow-up of AF ablation shows that short-term results cannot be considered permanent because AF recurrences are still present after the first year especially in patients who have had “PVI” strategy. PVI isolation plus LL is superior to the PVI strategy in maintaining SR without antiarrhythmic drugs after procedures 1 and 2 both in paroxysmal and persistent AF.

Long-term follow-up of right ventricular monomorphic extrasystoles.

OBJECTIVES The purpose of this study was to verify in a long-term follow-up whether frequent monomorphic right ventricle extrasystoles may progress to arrhythmogenic right ventricular dysplasia (ARVD). BACKGROUND Frequent monomorphic right ventricle extrasystoles are generally considered benign. However, in patients with this pattern, cardiac magnetic resonance (MR) has recently shown anatomical and functional abnormalities of the right ventricle. METHODS Sixty-one patients who had been classified by noninvasive examinations as having frequent idiopathic right ventricle ectopy were contacted after 15 +/- 2 years (12 to 20) and submitted to clinical examination, electrocardiogram (ECG), Holter monitoring, stress test, signal averaged ECG, echocardiography and, in 11 patients, cardiac MR. The primary end point was to ascertain the presence of cases of sudden death or progression to ARVD. RESULTS At the end of the follow-up, 55 patients were alive; six died, none of sudden death; eight stated to be well but refused further examinations. The 47 patients examined had normal ECG; in 24 patients (51%), extrasystoles were no longer present at Holter monitoring; late potentials were present in up to 15% of the patients; the right ventricle was normal at echocardiography. In 8 of 11 patients (73%), cardiac MR showed focal fatty replacement and other abnormalities of the right ventricle. CONCLUSIONS In this long-term follow-up study, no patient died of sudden death nor developed ARVD; two-thirds of the patients were asymptomatic, and, in half of the patients, ectopy had disappeared. Focal fatty replacement in the right ventricle was present in most.

Limited posterior left atrial cryoablation in patients with chronic atrial fibrillation undergoing valvular heart surgery

OBJECTIVES We sought to evaluate whether a limited surgical cryoablation of the posterior region of the left atrium was safe and effective in the cure of atrial fibrillation (AF) in patients with associated valvular heart disease. BACKGROUND Extensive surgical ablation of AF is a complex and risky procedure. The posterior region of the left atrium seems to be important in the initiation and maintenance of AF. METHODS In 32 patients with chronic AF who underwent heart valve surgery, linear cryolesions connecting the four pulmonary veins and the posterior mitral annulus were performed. Eighteen patients with AF who underwent valvular surgery but refused cryoablation were considered as the control group. RESULTS Sinus rhythm (SR) was restored in 25 (78%) of 32 patients immediately after the operation. The cryoablation procedure required 20 +/- 4 min. There were no intraoperative and perioperative complications. During the hospital period, one patient died of septicemia. Thirty-one patients reached a minimum of nine months of follow-up. Two deaths occurred but were unrelated to the procedure. Twenty (69%) of 29 patients remained in SR with cryoablation alone, and 26 (90%) of 29 patients with cryoablation, drugs and radiofrequency ablation. Three (10%) of 29 patients remained in chronic AF. Right and left atrial contractility was evident in 24 (92%) of 26 patients in SR. In control group, two deaths occurred, and SR was present in only four (25%) of 16 patients. CONCLUSIONS Linear cryoablation with lesions connecting the four pulmonary veins and the mitral annulus is effective in restoration and maintenance of SR in patients with heart valve disease and chronic AF. Limited left atrial cryoablation may represent a valid alternative to the maze procedure, reducing myocardial ischemic time and risk of bleeding.

Different patterns of atrial activation in idiopathic atrial fibrillation: simultaneous multisite atrial mapping in patients with paroxysmal and chronic atrial fibrillation

OBJECTIVES We aimed to evaluate: 1) the behavior of electrical activity simultaneously in different atrial regions during atrial fibrillation (AF); 2) the difference of atrial activation between paroxysmal and chronic AF; 3) the atrial refractoriness dispersion; and 4) the correlation between the effective refractory periods (ERPs) and the FF intervals. BACKGROUND Little data exist on the electrophysiologic characteristics of the different atrial regions in patients with AF. A more detailed knowledge of the electrical activity during AF may provide further insights to improve treatment of AF. METHODS Right and left atria were extensively mapped in 30 patients with idiopathic AF (18 paroxysmal and 12 chronic). In different atrial locations, we analyzed 1) the FF interval duration; and 2) the grade of organization and, in case of organized electrical activity, the direction of atrial activation. Furthermore, in patients with paroxysmal AF, we determined the atrial ERP, evaluated the ERP dispersion and assessed the presence of a correlation between the ERPs and the FF intervals. RESULTS In patients with chronic AF, we observed a shortening of the FF intervals and a greater prevalence of disorganized activity in all the atrial sites examined. In patients with paroxysmal AF, a significant dispersion of refractoriness was observed. The right lateral wall showed longer FF intervals and more organized atrial activity and, unexpectedly, the shortest mean ERPs. In contrast, the septal area showed shorter FF intervals, greater disorganization and the longest mean ERPs. CONCLUSIONS Electrical activity during AF showed a significant spatial inhomogeneity, which was more evident in patients with paroxysmal AF. The mean FF intervals did not correlate with the mean ERPs.

Adipose replacement and wall motion abnormalities in right ventricle arrhythmias: evaluation by MR imaging. Retrospective evaluation on 124 patients

We reevaluated the magnetic resonance (MR) examinations of 38 healthy volunteers (control group, CG) and of 124 patients with RV arrhythmia with left bundle branch block (LBBB) morphology: 45 with episodes of RV sustained tachycardia and of polymorphic RV premature beats (RVST-PPB group); 36 with only RV outflow tract sustained or not sustained tachycardia (RVOTT group); 43 with RV monomorphic premature beats (RVMPB group). All the examinations were reevaluated in a blinded fashion for detecting myocardial adipose replacement (AR) and wall bulges or aneurysms. In RVST-PPB patients, no AR was observed in 9%; 1 RV region involvement, 0%; 2 regions, 4%; ≥ 3 regions, 87%; left ventricle (LV), 15%. RVOTT patients: 28%, 53%, 14%, 5%, and 0%, respectively. RVMPB patients: 33%, 46%, 19%, 2%, and 0%, respectively. In CG, AR was observed in 11% (in RV outflow tract). RV bulges were detected in 75% of RVST-PPB , 39% of RVOTT, and 14% of RVMPB patients, none of the CG; RV aneurysms in 33% of RVST-PPB patients, none of RVOTT patients, RVMBP patients, and CG. A significant difference among groups for RV and LV AR as well as RV bulges and aneurysms was found (p < 0.0001). In the direct comparisons, significant differences were found for: disease duration (RVST-PPB vs. RVMPB, p = 0.0396); RV AR (all the patients groups vs. CG, RVST-PPB vs. RVOTT or RVMPB, p < 0.0001); RV aneurysms (RVST-PPB vs. CG. RVST-PPB vs. RVOTT or RVMPB, p < 0.0002); bulges (all comparisons, p < 0.0174). AR is confirmed as a structural substrate in RV arrhythmias. Number and extension of MR abnormalities are correlated to different degrees of RV arrhythmias.

Acute and long-term outcome of transvenous cryothermal catheter ablation of supraventricular arrhythmias involving the perinodal region.

Objective Cryoenergy is a new valuable treatment option to perform ablation close to the atrioventricular (AV) node in the cure of supraventricular tachycardias because of its favourable properties, such as the possibility of creating reversible lesions. The aim of this study was to report our experience on the effectiveness and safety of catheter cryoablation performed in “critical areas” to treat a large cohort of patients with supraventricular arrhythmias. Methods One hundred and thirty-one patients suffering from supraventricular tachycardias underwent catheter cryoablation using a 7F catheter. Eighty-seven patients presented with AV nodal re-entrant tachycardia (AVNRT), 39 had accessory pathways (APs) either manifest or concealed (15 midseptal, 24 parahissian), three had ectopic right atrial tachycardia (AT), and two patients had a permanent junctional reciprocating tachycardia (PJRT). When the optimal parameters were recorded, ice mapping at −30°C was performed for 80 s to validate the ablation site. If the expected result occurred, cryoablation was carried out by lowering the temperature to −75°C for 4 min. Results In two patients cryoablation was not performed because of technical reasons. Cryoablation was acutely successful in 84 out of 85 patients with AVNRT, in 37 of 39 with APs and in all patients with AT and PJRT. No complications occurred in any patient. Transient AV conduction impairment occurred in seven patients with midseptal APs and in two patients with AVNRT. In particular, in these patients no late permanent AV block was observed at follow-up. At a mean follow-up of 27 ± 12.9 months, clinical success rate was 87%. Conclusions Cryoablation is a safe and effective technique with a high success rate in the long term. It may be particularly useful when performing ablation close to the AV node or His bundle owing to the possibility of validating the ablation site with ice mapping, which creates only a reversible lesion, mainly in the midseptal APs.

Very long-term results of electroanatomic-guided radiofrequency ablation of atrial arrhythmias in patients with surgically corrected atrial septal defect

AIMS Atrial tachycardias are common after repair of atrial septal defect (ASD). Although ablation has shown promising results in the short and mid-term follow-up, little data regarding the very long-term success exist. Our aim was to assess very long-term follow-up in patients who have undergone electroanatomic-guided radiofrequency (RF) ablation of late-onset atrial arrhythmias after ASD surgery. METHODS AND RESULTS Forty-six consecutive patients with surgically repaired ASD were referred for atrial tachycardia ablation. Electrophysiological (EP) study and ablation procedure with the aid of an electroanatomic mapping (EAM) system were performed. Mean age was 49 ± 13 years (females 61%). The presenting arrhythmias were typical atrial flutter (48%), atypical atrial flutter (35%), and atrial tachycardia (17%). In 41% of patients, atrial fibrillation was also present. The EP study showed a right atrial macroreentrant circuit in all the patients. In 12 of 46 (26%), the circuit was localized in the cavo-tricuspid isthmus, whereas in the remaining 34 patients (74%) was atriotomy-dependent. Acute success was 100%. Clinical arrhythmia recurred in 24% of the patients. Nine patients underwent a second and two a third ablation procedure, reaching an overall efficacy of 87% (40 of 46) at a mean follow-up of 7.3 ± 3.8 years since the last procedure. With antiarrhythmic drugs the success rate increased to 96% (44 of 46). No complications occurred. CONCLUSION In patients with surgically corrected ASD, EAM-guided RF ablation of late-onset macroreentrant atrial arrhythmias demonstrated a high success rate in a very long-term follow-up. Therefore, RF ablation could be considered early in the management of late-onset macroreentrant atrial tachycardias.

Relationship of ECG findings to phenotypic expression in patients with hypertrophic cardiomyopathy: A cardiac magnetic resonance study ☆

BACKGROUND The 12-lead electrocardiogram (ECG) is considered an essential screening tool for hypertrophic cardiomyopathy (HCM). A vast array of ECG abnormalities has been described in HCM, although their relationship to left ventricle (LV) morphology and degree of hypertrophy appears elusive. Aim of this study was to assess the relationship of ECG patterns with the HCM phenotype assessed according to the novel opportunities offered by cardiac magnetic imaging (CMR). METHODS CMR and 12-lead ECG were performed in 257 HCM patients. Severity of ECG abnormalities was defined by the sum of 9 criteria: abnormal cardiac rhythm, QRS duration ≥ 100 ms, Romhilt-Estes score ≥ 5, fascicular block (LAHB) and/or bundle-branch block (LBBB or RBBB), ST-T abnormalities, ST-T segment elevation ≥ 0.2 mV, prolonged QTc interval, pathological Q waves, absence of normal Q wave. Four ECG groups were identified: normal (0 criteria); mildly abnormal (1-3 criteria); moderately abnormal (4-6 criteria); markedly abnormal (7-9 criteria). RESULTS There was a direct relationship between severity of ECG abnormalities and HCM phenotype. LV mass index was normal in most patients with normal ECG and progressively increased with each class of ECG score, from 70.9 ± 18.6g/m(2) in patients with normal ECG to 107.1 ± 55.1g/m(2) among those with markedly abnormal ECG (p=<0.0001). Likewise, the prevalence and extent of late gadolinium enhancement (LGE) increased significantly with the ECG score, from 37% in patients with normal ECG to 93% in patients with markedly abnormal ECG (overall p=0.0012). A normal ECG had a negative predictive accuracy of 96% for markedly increased LV mass (>91 g/m(2) for men and >69 g/m(2) for women), and of 100% for maximum LV thickness ≥ 30 mm. CONCLUSIONS In a large HCM cohort, the number and severity of ECG abnormalities were directly related to phenotypic expression as revealed by CMR. Although false negative ECG findings remain a challenge in population screenings for HCM, a normal ECG proved effective in ruling out severe LV hypertrophy, suggesting potential implications for long-term follow-up of HCM patients and family members. A simple score for quantification of ECG abnormalities in HCM patients is proposed.

Should stimulation therapy for congestive heart failure be combined with defibrillation backup

Biventricular pacing has been proposed to resynchronize ventricular contraction in patients with congestive heart failure (CHF) and interventricular conduction delay. However, the sudden death rate is still high despite the improvement in cardiac performance. Devices combining biventricular pacing with implantable cardioverter defibrillator (ICD) backup are now under clinical investigation to demonstrate whether they can decrease sudden death. From the first implant of an ICD with biventricular transvenous pacing on August 1998 to April 2000, 96 patients underwent such implants: 67 (70%) received pacemakers alone and 29 (30%), who had class I ICD indications, received combined pacemaker/ICD systems. During a mean follow-up of 283 +/- 170 days, 13 (14%) patients died: 5 of 29 (17%) in the ICD group and 8 of 67 (12%) in the pacemaker group. A total of 15 patients (52%) had ICD shocks and 6 patients (21%) had 113 episodes of ventricular tachyarrhythmias, of which 96 (85%) were converted to sinus rhythm with antitachypacing. The echocardiograms showed a narrowing of the delay between the onset of right and left ventricular outflow from 40 +/- 37 msec to 17 +/- 16 msec (p = 0.03) and a reduction of the mitral regurgitation area from 7 +/- 3.8 cm2 to 5 +/- 4 cm2 (p = 0.04) at 3 months. Functional class improved from 2.8 +/- 0.7 to 1.6 +/- 0.5 (p <0.001) 3 months after implant. Thus, ischemic patients with reduced left ventricular ejection fraction and ventricular tachyarrhythmias seem good candidates for biventricular pacing with ICD backup. The sudden death risk for those with idiopathic dilated cardiomyopathy, however, is difficult to stratify, and the choice of ICD backup has to be considered on the basis of patient safety, as well as of costs.

Zero-Fluoroscopy Ablation of Accessory Pathways in Children and Adolescents: CARTO3 Electroanatomic Mapping Combined with RF and Cryoenergy.

Fluoroscopic catheter ablation of cardiac arrhythmias in pediatric patients exposes the patients to the potential risk of radiation considering the sensitivity of this population and its longer life expectancy. We evaluated the feasibility, safety, and efficacy of accessory pathway (AP) ablation guided by CARTO3 electroanatomic mapping (EAM) system with both cryoenergy and radiofrequency (RF) energy in order to avoid x‐ray exposure in pediatric patients.