Heinz-Friedrich Pitschner

Circumferential Pulmonary Vein Isolation With the Cryoballoon Technique: Results From a Prospective 3-Center Study

OBJECTIVES The purpose of this study was to investigate the efficacy safety of the novel cryoballoon device (Arctic Front, Cryocath, Quebec, Canada). BACKGROUND Antral pulmonary vein (PV) ablation with radiofrequency energy is widely used as a strategy for catheter ablation of paroxysmal atrial fibrillation (PAF). A novel double lumen cryoballoon catheter was designed for circumferential pulmonary vein isolation (PVI) with the cryoablation technique. METHODS We consecutively enrolled 346 patients with symptomatic, drug refractory paroxysmal (n = 293) or persistent (n = 53) atrial fibrillation (AF). In all patients, PVI of all targeted PVs was the therapeutic aim. The primary end points of this nonrandomized study were: 1) acute isolation rate of targeted PV; and 2) first electrocardiogram-documented recurrence of AF. The secondary end point was occurrence of PV stenosis or atrio-esophageal fistula. RESULTS The 1,360 of 1,403 PVs (97%) were targeted with balloons or balloons in combination with the use of Freezor Max (Cryocath). We found that ablation with the cryoballoon resulted in maintenance of sinus rhythm in 74% of patients with PAF and 42% of patients with persistent AF. No PV narrowing occurred. The most frequent complication was right phrenic nerve palsy observed during cryoballoon ablation at the right superior PV. CONCLUSIONS Pulmonary vein isolation with a new cryoballoon technique is feasible. Sinus rhythm can be maintained in the majority of patients with PAF by circumferential PVI using a cryoballoon ablation system. Cryoablation was less effective in patients with persistent AF than in patients with PAF.

Catheter ablation of stable ventricular tachycardia before defibrillator implantation in patients with coronary heart disease (VTACH): a multicentre randomised controlled trial

BACKGROUND In patients with ventricular tachycardia (VT) and a history of myocardial infarction, intervention with an implantable cardioverter defibrillator (ICD) can prevent sudden cardiac death and thereby reduce total mortality. However, ICD shocks are painful and do not provide complete protection against sudden cardiac death. We assessed the potential benefit of catheter ablation before implantation of a cardioverter defibrillator. METHODS The Ventricular Tachycardia Ablation in Coronary Heart Disease (VTACH) study was a prospective, open, randomised controlled trial, undertaken in 16 centres in four European countries. Patients aged 18-80 years were eligible for enrolment if they had stable VT, previous myocardial infarction, and reduced left-ventricular ejection fraction (LVEF; <or=50%). 110 patients were randomly allocated in a 1:1 ratio to receive catheter ablation and an ICD (ablation group, n=54) or ICD alone (control group, n=56). Randomisation was done by computer-generated randomly permuted blocks and stratified by centre and LVEF (<or=30% or >30%). Patients were followed up for at least 1 year. The primary endpoint was the time to first recurrence of VT or ventricular fibrillation (VF). Analysis was by intention to treat (ITT). This study is registered with ClinicalTrials.gov, number NCT00919373. FINDINGS 107 patients were included in the ITT population (ablation group, n=52; control group, n=55). Two patients (one in each group) withdrew consent immediately after randomisation without any follow-up data and one patient (ablation group) was excluded because of a protocol violaton. Mean follow-up was 22.5 months (SD 9.0). Time to recurrence of VT or VF was longer in the ablation group (median 18.6 months [lower quartile 2.4, upper quartile not determinable]) than in the control group (5.9 months [IQR 0.8-26.7]). At 2 years, estimates for survival free from VT or VF were 47% in the ablation group and 29% in the control group (hazard ratio 0.61; 95% CI 0.37-0.99; p=0.045). Complications related to the ablation procedure occurred in two patients; no deaths occurred within 30 days after ablation. 15 device-related complications requiring surgical intervention occurred in 13 patients (ablation group, four; control group, nine). Nine patients died during the study (ablation group, five; control group, four). INTERPRETATION Prophylactic VT ablation before defibrillator implantation seemed to prolong time to recurrence of VT in patients with stable VT, previous myocardial infarction, and reduced LVEF. Prophylactic catheter ablation should therefore be considered before implantation of a cardioverter defibrillator in such patients. FUNDING St Jude Medical.

Cryoablation Versus Radiofrequency Energy for the Ablation of Atrioventricular Nodal Reentrant Tachycardia (the CYRANO Study) Results From a Large Multicenter Prospective Randomized Trial

Background— Cryoablation has emerged as an alternative to radiofrequency catheter ablation (RFCA) for the treatment of atrioventricular (AV) nodal reentrant tachycardia (AVNRT). The purpose of this prospective randomized study was to test whether cryoablation is as effective as RFCA during both short-term and long-term follow-up with a lower risk of permanent AV block. Methods and Results— A total of 509 patients underwent slow pathway cryoablation (n=251) or RFCA (n=258). The primary end point was immediate ablation failure, permanent AV block, and AVNRT recurrence during a 6-month follow-up. Secondary end points included procedural parameters, device functionality, and pain perception. Significantly more patients in the cryoablation group than the RFCA group reached the primary end point (12.6% versus 6.3%; P=0.018). Whereas immediate ablation success (96.8% versus 98.4%) and occurrence of permanent AV block (0% versus 0.4%) did not differ, AVNRT recurrence was significantly more frequent in the cryoablation group (9.4% versus 4.4%; P=0.029). In the cryoablation group, procedure duration was longer (138±54 versus 123±48 minutes; P=0.0012) and more device problems occurred (13 versus 2 patients; P=0.033). Pain perception was lower in the cryoablation group (P<0.001). Conclusions— Cryoablation for AVNRT is as effective as RFCA over the short term but is associated with a higher recurrence rate at the 6-month follow-up. The risk of permanent AV block does not differ significantly between cryoablation and RFCA. The potential benefits of cryoenergy relative to ablation safety and pain perception are counterbalanced by longer procedure times, more device problems, and a high recurrence rate. Clinical Trial Registration— URL: http://www.clinicaltrials.gov. Unique identifier: NCT00196222.

MEDAFI-Trial (Micro-embolization during ablation of atrial fibrillation): comparison of pulmonary vein isolation using cryoballoon technique vs. radiofrequency energy

AIMS Cerebral embolism is a possible serious complication during catheter ablation of atrial fibrillation (AF). The purpose of this prospective pilot study was to analyse the incidence and possible impact of cryo ablation on cerebral lesions and possible differences to radiofrequency (RF) ablation during pulmonary vein isolation (PVI). METHODS AND RESULTS Pulmonary vein isolation was performed in 89 patients, either with the cryoballoon technique (n = 45) or with RF ablation (n = 44). Phenprocoumon was stopped 3 days before intervention and replaced by subcutaneous low-molecular-weight heparin. During the catheter procedure, an infusion of unfractionated heparin was maintained to achieve an activated clotting time (ACT) of > 300 s. Cerebral magnetic resonance imaging scans were performed 1 day before and after PVI, and at 3-month follow-up. Chronic lesions were observed in 11 patients (12.3%) before PVI without statistically significant difference between the two groups. None of the patients had neurological symptoms during or following the procedure. Seven patients (7.9%) developed acute lesions 1 day after PVI, without statistically significant difference between the group treated by cryoenergy (8.9%) and RF ablation (6.8%). Patients with acute lesions were significantly older compared with those without acute cerebral lesions. No additional cerebral lesions during follow-up were observed. CONCLUSION A considerable portion of patients with AF but without any neurological symptoms had chronic cerebral lesions before PVI. Additional acute lesions could be added after the procedure. Both ablation techniques showed additional cerebral acute lesions with no neurological symptoms after PVI.

Neuropsychological decline after catheter ablation of atrial fibrillation

BACKGROUND Cerebral embolic events represent recognized side effects after catheter ablation in the treatment of recurrent atrial fibrillation (AF). OBJECTIVE The study was performed to analyze the neuropsychological outcome and to detect new embolic ischemic brain lesions after therapeutic left atrial catheter ablation of AF. METHODS We enrolled 23 patients with recurrent AF who underwent elective circumferential pulmonary vein isolation. The primary endpoint was the neuropsychological outcome 3 months after intervention in contrast to the results of non-AF controls (n = 23) without ablation and in covariance of baseline performance. Cerebral diffusion-weighted magnetic resonance imaging (DWI) was performed in 21 AF patients at baseline, 2-4 days, and 3 months after intervention. RESULTS In 3/21 patients (14.3%), new ischemic lesions were detected on DWI shortly after intervention. In one patient, a territorial middle cerebral artery infarct occurred with severe clinical symptoms. The other two patients represented clinically silent small lesions. In contrast to the control group and in covariance of baseline performance, the ablation group showed worse neuropsychological outcome in verbal memory (one of five cognitive domains) with an effect size of d = 0.93[t (.05; 42) = -3.53; P < .001; false discovery rate (FDR)(crit) ≤ .01]. CONCLUSION Adverse neuropsychological changes after left atrial catheter ablation are verifiable in verbal memory and, conjoined with ischemic brain lesions on DWI, might represent cerebral side effects of this procedure.

Invasive optimization of cardiac resynchronization therapy: role of sequential biventricular and left ventricular pacing.

Background: Aim of this invasive study was to characterize and quantify changes in left ventricular (LV) systolic function due to sequential biventricular pacing (BV) as compared to right atrial triggered simultaneous BV (BV0), LV, and right ventricular (RV) pacing in patients with congestive heart failure (CHF).

Comparison of generic health survey SF-36 and arrhythmia related symptom severity check list in relation to post-therapy AF recurrence

AIM The effect of applied therapy on quality of life (QoL) in patients with atrial fibrillation (AF) was investigated in recent studies. However, no information on clinical relevance of QoL assessing instruments in relation to post-ablation recurrence of AF is currently available. The aim of this study was to evaluate the clinical relevance of SF-36 and Arrhythmia Related Symptom Severity Check List (SSCL) to post-procedure AF recurrences in patients with paroxysmal AF undergoing pulmonary vein isolation (PVI). METHODS AND RESULTS Sixty consecutive patients with AF were enroled in the study. The QoL was measured using SF-36 scale and SSCL. The questionnaires were administered at baseline then 3, 6, 9 and 12 months after the procedure. In order to define statistical power in relation to AF recurrence the scores were dichotomized. Positive and negative predictive accuracy (PPA, NPA) and test efficiency (sum of PPA and NPA) were calculated. Twenty-one out of 60 patients experienced a total of 66 recurrences of AF during follow-up. The parameters of SF-36 provided maximum test efficiency of 1.36, whereas the test efficiency of SSCL was 1.79. CONCLUSION We conclude that SSCL is more specific instrument for a measurement of PVI success or failure.

Cardiac Gene Defects Can Cause Sudden Cardiac Death in Young People

BACKGROUND In Europe, sudden cardiac death (SCD) is one of the most common causes of death. Although sudden cardiac death usually happens in older people, 5% to 10% of the affected individuals are young and apparently healthy. Sudden death in infants, children, and young adults is relatively rare, with an incidence of 1 to 5 per 100 000 persons per year. Nonetheless, up to 7000 asymptomatic children die in the USA each year, almost half of them without any warning signs or symptoms. METHOD Selective literature review. RESULTS Although structural cardiovascular abnormalities explain most cases of sudden cardiac death in young people, the cause of death remains unexplained after autopsy in 10% to 30% of cases. Potentially lethal ion channel disorders (channelopathies) such as the long QT syndromes (LQTS), catecholaminergic polymorphic ventricular tachycardia (CPVT), and the Brugada syndrome (BrS) may account for at least one-third of these unexplained cases. Most of these diseases are hereditary with autosomal-dominant transmission, i.e., there is a 50% chance that the children of affected individuals will be affected themselves. CONCLUSIONS Post-mortem genetic screening for sequence variations in cardiac ion channel genes has become an important forensic tool for elucidating the cause of sudden cardiac death. Moreover, it allows the identification of other family members bearing the previously undiagnosed gene defect, who can then undergo a cardiological evaluation if indicated by their clinical history.

Prospective randomized comparison of durability of bidirectional conduction block in the cavotricuspid isthmus in patients after ablation of common atrial flutter using cryothermy and radiofrequency energy: The CRYOTIP study

BACKGROUND Recent studies have shown that cryoablation and radiofrequency (RF) ablation are comparable with regard to success rates and safety in the treatment of common atrial flutter (AFL). Long-term success requires persistence of bidirectional conduction block (BCB) in the inferior cavotricuspid isthmus (CTI). OBJECTIVE The purpose of this study was to determine the persistence of BCB in a prospective randomized multicenter trial of the two ablation techniques. METHODS A total of 191 patients were randomized to RF ablation or cryoablation of the CTI using an 8-mm-tip catheter. In all patients, BCB was defined as the ablation end-point. Primary end-point of the study was nonpersistence of achieved BCB and/or ECG-documented relapse of common AFL within 3-month follow-up. RESULTS Acute success rates were 91% (83/91) in the RF group and 89% (80/90) in the cryoablation group (P = NS). Invasive follow-up after 3 months with repeated electrophysiologic study was available for 60 patients in the RF group and 64 patients in the cryoablation group. Persistent BCB could be confirmed in 85% of the RF group versus 65.6% of the cryoablation group. The primary end-point was achieved in 15% of the RF group and 34.4% of the cryoablation group (P = .014). As a secondary end-point, pain perception during ablation was significant lower in the cryoablation group (P <.001). CONCLUSION Persistence of BCB in patients treated with cryoablation reinvestigated after 3 months is inferior to that patients treated with RF ablation, as evidenced by the higher recurrence rate of common AFL seen in this study.

Doppelte Ventrikelerregung bei dualer AV-Knoten-Leitungsphysiologie : Katheterablation des langsamen Leitungsweges des dualen AV-knotens

A variety of electrocardiographic manifestations of dual AV nodal physiology have been reported. The specific subtype dual ventricular response is considered as a very rare phenomenon. We present the case of a 53 year old lady who suffered from paroxysmal regular tachycardias for more than seven years. In the last 6 months the symptomatology of the cardiac arrhythmia changed to more persistent und irregular rhythm disturbances. Treatment with class Ia antiarrhythmic drugs and beta-blocking agents failed. The latter even seemed to worsen her very disturbing palpitations. After examination of the ECG recordings, the diagnosis of dual AV nodal physiology with double ventricular response was made – the lady was referred to our institution for electrophysiological testing and radiofrequency catheter ablation of the slow pathway. An invasive electrophysiological study reconfirmed the diagnosis of a dual AV nodal conduction pattern with irregular double ventricular response. The radiofrequency catheter ablation of the the slow pathway achieved a complete cessation of the double ventricular response. This satisfactory outcome was confirmed by analysis of a postinterventional 24hour holter recording and an exercise stress test. During a follow-up period of three months, the patient remained free of symptoms and there was no recurrence of dual AV nodal conduction physiology in the surface ECG. Unterschiedliche elektrokardiographische Manifestationen einer dualen AV-Knoten-Leitungsphysiologie sind beschrieben. Ein besonders selten auftretender Subtyp stellt hier die doppelte ventrikuläre Erregung dar. Wir berichten über eine 53-jährige Patientin mit über sieben Jahren bestehenden typischen paroxysmalen regelmäßigen Tachykardien. In den vergangenen sechs Monaten kam es zu einer Änderung der vorbestehenden Symptomatologie der Herzrhythmusstörungen mit einem Wechsel zu länger anhaltenden und irregulär empfundenen Rhythmusstörungen. Medikamentöse Behandlungsversuche mit Antiarrhythmika der Klasse I waren nicht erfolgreich. Ein Therapieversuch mit Beta-Blockern verstärkte die subjektiven Beschwerden. Nach erneuter Befundung des EKG der Patientin wurde vom zuweisenden Krankenhaus die Diagnose einer dualen AV-nodalen Leitungsphysiologie mit doppelter Ventrikelerregung gestellt und die Patientin unserer Klinik zur invasiven elektrophysiologischen Untersuchung und zur Katheterablation des langsamen Leitungsweges des dualen AV-Knotens zugewiesen. Die invasive elektrophysiologische Untersuchung bestätigte die Diagnose eines dualen AV-Knotens mit doppelter Ventrikelerregung. Die Hochfrequenz-Katheterablation der langsamen Leitungsbahn erreichte die vollständige Unterbrechung der doppelten Ventrikelerregung. Das erfolgreiche Ablationsergebnis konnte durch Langzeit-EKG-Registrierung und Belastungsergometrie weiterführend bestätigt werden. Während einer dreimonatigen Nachbeobachtung blieb die Patientin vollständig asymptomatisch und es kam zu keiner Wiedererholung der dualen AV-Knoten Leitungsphysiologie im Oberflächen-EKG.