Yves De Greef

Prevalence, Characteristics, and Predictors of Pulmonary Vein Narrowing After Isolation Using the Pulmonary Vein Ablation Catheter

Background —The risk of pulmonary vein narrowing (PVN) after pulmonary vein isolation (PVI) using a novel multi-electrode ablation catheter (PVAC) is unknown. Methods and Results —Left atrial (LA) volume and PV diameters (PVD) were compared by computed tomography before and 3 months after PVI using duty-cycled phased RF energy (2:1 or 4:1 bipolar/unipolar ratio) in 50 patients. PVD was measured in a coronal and axial view at three levels (A=ostium, B=1cm more distal, C=2cm more distal). Moderate PVN was defined as a PVD reduction of 25-50%, severe PVN as > 50%. LA volume decreased by 12±12% (p<0.01). Axial PVD shortened by a median of 16% (IQR 28% to 5%) , 13% (IQR 25% to 5%) and 9% (IQR 21% to -3%) at level A, B and C respectively (p<0.01 for all); coronal PVD decreased by a median of 6% (IQR 24% to 7%), 11% (IQR 21% to 4%) and 8% (IQR 18% to -2%) (p<0.01 for all). Moderate PVN occurred in 30% of the PVs, in 78% of the patients; severe PVN occurred in 4% of the PVs, in 15% of the patients. PV diameter reduction was not related to changes in LA volume. Conclusions —PVAC ablation results in a consistent moderate reduction of the PV diameters predominantly at the ostium. Severe PVN in 15% of patients raises concerns about the risk for clinical PV stenosis.Background— The risk of pulmonary vein narrowing (PVN) after pulmonary vein isolation, using a novel multi-electrode ablation catheter, is unknown. Methods and Results— Left atrial volume and PV diameters were compared by computed tomography (CT) before and 3 months after pulmonary vein isolation using duty-cycled phased radio frequency energy (2:1 or 4:1 bipolar/unipolar ratio) in 50 patients. Pulmonary vein diameter was measured in a coronal and axial view at 3 levels (A, ostium; B, 1 cm more distal; C, 2 cm more distal). Moderate PVN was defined as a pulmonary vein diameter reduction of 25 to 50%, and severe PVN as >50%. Left atrial volume decreased by 12±12% (P<0.01). Axial pulmonary vein diameter shortened by a median of 16% (interquartile range [IQR] 28 to 5%), 13% (IQR 25 to 5%), and 9% (IQR 21 to −3%) at level A, B, and C, respectively (P<0.01 for all); coronal pulmonary vein diameter decreased by a median of 16% (IQR 24 to 7%), 11% (IQR 21 to 4%), and 8% (IQR 18 to −2%; P<0.01 for all). Moderate PVN occurred in 30% of the PVs, in 78% of the patients; severe PVN occurred in 4% of the PVs, in 15% of the patients. PV diameter reduction was not related to changes in left atrial volume. Conclusions— Isolation of the pulmonary veins using a multielectrode ablation catheter and duty cycled phased radiofrequency energy delivery results in a consistent moderate reduction of the PV diameters predominantly at the ostium. Severe PVN in 15% of patients raises concerns about the risk for clinical PV stenosis.

Prevalence, Characteristics and Predictors of Pulmonary Vein Narrowing after PVAC Ablation

Background —The risk of pulmonary vein narrowing (PVN) after pulmonary vein isolation (PVI) using a novel multi-electrode ablation catheter (PVAC) is unknown. Methods and Results —Left atrial (LA) volume and PV diameters (PVD) were compared by computed tomography before and 3 months after PVI using duty-cycled phased RF energy (2:1 or 4:1 bipolar/unipolar ratio) in 50 patients. PVD was measured in a coronal and axial view at three levels (A=ostium, B=1cm more distal, C=2cm more distal). Moderate PVN was defined as a PVD reduction of 25-50%, severe PVN as > 50%. LA volume decreased by 12±12% (p<0.01). Axial PVD shortened by a median of 16% (IQR 28% to 5%) , 13% (IQR 25% to 5%) and 9% (IQR 21% to -3%) at level A, B and C respectively (p<0.01 for all); coronal PVD decreased by a median of 6% (IQR 24% to 7%), 11% (IQR 21% to 4%) and 8% (IQR 18% to -2%) (p<0.01 for all). Moderate PVN occurred in 30% of the PVs, in 78% of the patients; severe PVN occurred in 4% of the PVs, in 15% of the patients. PV diameter reduction was not related to changes in LA volume. Conclusions —PVAC ablation results in a consistent moderate reduction of the PV diameters predominantly at the ostium. Severe PVN in 15% of patients raises concerns about the risk for clinical PV stenosis.Background— The risk of pulmonary vein narrowing (PVN) after pulmonary vein isolation, using a novel multi-electrode ablation catheter, is unknown. Methods and Results— Left atrial volume and PV diameters were compared by computed tomography (CT) before and 3 months after pulmonary vein isolation using duty-cycled phased radio frequency energy (2:1 or 4:1 bipolar/unipolar ratio) in 50 patients. Pulmonary vein diameter was measured in a coronal and axial view at 3 levels (A, ostium; B, 1 cm more distal; C, 2 cm more distal). Moderate PVN was defined as a pulmonary vein diameter reduction of 25 to 50%, and severe PVN as >50%. Left atrial volume decreased by 12±12% (P<0.01). Axial pulmonary vein diameter shortened by a median of 16% (interquartile range [IQR] 28 to 5%), 13% (IQR 25 to 5%), and 9% (IQR 21 to −3%) at level A, B, and C, respectively (P<0.01 for all); coronal pulmonary vein diameter decreased by a median of 16% (IQR 24 to 7%), 11% (IQR 21 to 4%), and 8% (IQR 18 to −2%; P<0.01 for all). Moderate PVN occurred in 30% of the PVs, in 78% of the patients; severe PVN occurred in 4% of the PVs, in 15% of the patients. PV diameter reduction was not related to changes in left atrial volume. Conclusions— Isolation of the pulmonary veins using a multielectrode ablation catheter and duty cycled phased radiofrequency energy delivery results in a consistent moderate reduction of the PV diameters predominantly at the ostium. Severe PVN in 15% of patients raises concerns about the risk for clinical PV stenosis.

Low rate of asymptomatic cerebral embolism and improved procedural efficiency with the novel pulmonary vein ablation catheter GOLD: results of the PRECISION GOLD trial

Abstract Aims This prospective, multicentre study (PRECISION GOLD) evaluated the incidence of asymptomatic cerebral embolism (ACE) after pulmonary vein isolation (PVI) using a new gold multi-electrode radiofrequency (RF) ablation catheter, pulmonary vein ablation catheter (PVAC) GOLD. Also, procedural efficiency of PVAC GOLD was compared with ERACE. The ERACE study demonstrated that a low incidence of ACE can be achieved with a platinum multi-electrode RF catheter (PVAC) combined with procedural manoeuvres to reduce emboli. Methods and results A total of 51 patients with paroxysmal atrial fibrillation (AF) (age 57 ± 9 years, CHA2DS2-VASc score 1.4 ± 1.4) underwent AF ablation with PVAC GOLD. Continuous oral anticoagulation using vitamin K antagonists, submerged catheter introduction, and heparinization (ACT ≥ 350 s prior to ablation) were applied. Cerebral magnetic resonance imaging (MRI) scans were performed within 48 h before and 16–72 h post-ablation. Cognitive function assessed by the Mini-Mental State Exam at baseline and 30 days post-ablation. New post-procedural ACE occurred in only 1 of 48 patients (2.1%) and was not detectable on MRI after 30 days. The average number of RF applications per patient to achieve PVI was lower in PRECISION GOLD (20.3 ± 10.0) than in ERACE (28.8 ± 16.1; P = 0.001). Further, PVAC GOLD ablations resulted in significantly fewer low-power (<3 W) ablations (15 vs. 23%, 5 vs. 10% and 2 vs. 7% in 4:1, 2:1, and 1:1 bipolar:unipolar energy modes, respectively). Mini-Mental State Exam was unchanged in all patients. Conclusion Atrial fibrillation ablation with PVAC GOLD in combination with established embolic lowering manoeuvres results in a low incidence of ACE. Pulmonary vein ablation catheter GOLD demonstrates improved biophysical efficiency compared with platinum PVAC. Trial registration ClinicalTrials.gov NCT01767558.

Lessons from dissociated pulmonary vein potentials: entry block implies exit block

Aims Prior reports using pacing manoeuvres, demonstrated an up to 42% prevalence of residual pulmonary vein to left atrium (PV–LA) exit conduction after apparent LA–PV entry block. We aimed to determine in a two-centre study the prevalence of residual PV–LA exit conduction in the presence of unambiguously proven entry block and without pacing manoeuvres. Methods and results Of 378 patients, 132 (35%) exhibited spontaneous pulmonary vein (PV) potentials following circumferential PV isolation guided by three-dimensional mapping and a circular mapping catheter. Pulmonary vein automaticity was regarded as unambiguous proof of LA–PV entry block. We determined the prevalence of spontaneous exit conduction of the spontaneous PV potentials toward the LA. Pulmonary vein automaticity was observed in 171 PVs: 61 right superior PV, 33 right inferior PV, 47 left superior PV, and 30 left inferior PV. Cycle length of the PV automaticity was >1000 ms in all cases. Spontaneous PV–LA exit conduction was observed in one of 171 PVs (0.6%). In a subset of 69 PVs, pacing from within the PV invariably confirmed PVLA exit block. Conclusion Unidirectional block at the LA–PV junction is unusual (0.6%). This observation is supportive of LA–PV entry block as a sufficient electrophysiological endpoint for PV isolation.

Pulmonary vein stenosis after pulmonary vein ablation catheter–guided pulmonary vein isolation

ase report he patient was a 44-year-old man with highly symptomatic aroxysmal atrial fibrillation (AF). The paroxysms of AF ad started 6 years earlier and initially had been treated with lass IC and Class III antiarrhythmic drugs. He was referred or invasive treatment due to persistent symptomatic AF aroxysms despite medical therapy and after he developed evere side effects of amiodarone treatment (photosensitivty and thyroid dysfunction). No evidence of underlying ardiac disease was noted. Left atrial (LA) diameter on ransthoracic echocardiographic parasternal long-axis view as 44 mm. Contrast-enhanced computed tomography (40 lices, Philips, Eindhoven, The Netherlands) was performed he day before ablation.

Pulmonary vein isolation with the 30 and 35 mm high-density mesh ablator

AIMS To analyse procedural results and clinical outcome of paroxysmal atrial fibrillation (AF) ablation using the 30 and 35 mm high-density mesh ablator (HDMA, Bard Electrophysiology). METHODS AND RESULTS Sixty-four consecutive patients were ablated with the HDMA catheter (26 with the 30 mm, 38 with the 35 mm device). If pulmonary vein (PV) isolation was unsuccessful, ablation was continued using a conventional 4 mm ablation catheter. Success was defined as freedom of AF at 6 months after a single procedure without antiarrhythmic drugs. PV isolation could be obtained in 84/106 (79%) PVs in the 30 mm group vs. 149/153 (97%) PVs in the 35 mm group (P < 0.001). All non-isolated veins were successfully isolated with the conventional 4 mm ablation catheter. Freedom of AF at 6 months was 19% in the 30 mm group vs. 18% in the 35 mm group (P = NS). During a repeat procedure in 19 patients, 69% of the PVs were reconnected with an incremental LA-PV delay of 11 ± 15 ms compared with baseline. CONCLUSION (i) Compared with the 30 mm, the 35 mm HDMA catheter proves to be more efficient in obtaining acute pulmonary vein isolation, (ii) despite these promising procedural results, the clinical outcome is disappointing and (iii) the high reconnection rate and the limited delay in PV potentials suggest that PV isolation with the HDMA catheter is not permanent.

Subacute implantable cardioverter defibrillator lead perforation: a potentially life-threatening event

We describe a 74-year-old man presenting with a life-threatening left-sided haemothorax as a result of an implantable cardioverter defibrillator lead perforation occurring 1 month after implantation.

Efficacy and safety of the second generation cryoballoon ablation for the treatment of paroxysmal atrial fibrillation in patients over 75 years: a comparison with a younger cohort

Aims In this double centre, retrospective study, we aimed to analyse the 1-year efficacy and safety of cryoballoon ablation (CB-A) in patients older than 75 years compared with those younger than 75-years old. Methods and results Fifty-three consecutive patients aged 75 years or older with drug-resistant paroxysmal AF (PAF) who underwent pulmonary vein isolation (PVI) by the means of second generation CB-A, were compared with 106 patients aged <75 years. The mean age in the study group (>75 years) was 78.19 ± 2.7 years and 58.97 ± 8.5 in the control group. At 1-year follow-up the global success rate was 83.6% and did not significantly differ between older (10/53) and younger patients (16/106) (81.1 vs. 84.9%, P = 0.54). Transient phrenic nerve palsy was the most common complication which occurred in eight patients in the younger group and in three in the older group (7.5 vs. 5.7%, respectively, P = 0.66). Conclusions The results of our study showed that CB-A for the treatment of PAF is a feasible and safe procedure in elderly patients, with similar success and complications rates when compared with a younger population.

Percutaneous catheter ablation of atrial fibrillation in a patient with an anomalous pulmonary venous connection.

A 62-year-old patient was referred for the treatment of highly symptomatic and drug-resistant paroxysmal atrial fibrillation (AF). First AF paroxysm occurred as early as 1992. At that time, patient was diagnosed with a partial anomalous pulmonary venous connection (PAPVC) without atrial septal defect (ASD). Now repetitive Holter monitoring revealed paroxysms of sustained AF. Transthoracic echocardiogram showed a right ventricular end-diastolic diameter of 44 mm, a systolic pulmonary arterial pressure of 52 mmHg, and a shunt ratio of 2.13. Left atrial (LA) diameter (PS-LAX) was 41 mm. Right atrium (RA) was dilated with a surface area of 24 cm2. Surgical repair of the anomalous pulmonary veins (PVs) …

Atrial fibrillation ablation with the second generation cryoballoon: Multicenter propensity score matched comparison between freezing strategies

BACKGROUND Second generation cryoballoon (CB-A) ablation is highly effective in achieving pulmonary vein (PV) isolation and freedom from atrial fibrillation (AF). However, the ideal freezing strategy is still under debate. Our objective was to investigate the efficacy and outcome between different freezing strategies used with the CB-A in a multicenter, matched population. METHODS From a total cohort of 1018 patients having undergone CB-A ablation for drug-refractory AF, 673 patients with follow-up ≥6months were included and stratified according to the applied freezing strategy: bonus freeze (BF) versus single freeze (SF). Final population of 256 BF patients was compared with 256 propensity-score matched SF patients. RESULTS BF strategy consisted of 3 different protocols: 3cycles of 180s; 2cycles of 240s; and cycles of 240s followed by 180s in 99/256 (39%); 42/256 (16%); and 115/256 (45%) patients, respectively. SF approach included cycles of 240s in 23/256 (9%), and 180s in 233/256 (91%) patients. Electrical isolation could be achieved in all PVs by both protocols, with shorter procedure and fluoroscopy times in the SF group (mean 106 vs 65min, and 18 vs 14min, respectively, P<0.001). Phrenic nerve palsy persisted after discharge in a total of 11 patients (2.1%): 4 (1.6%) in the BF group vs 7 (2.7%) in the SF group, P=0.5. AF-free survival was similar between the 2 groups during follow-up (mean 18±10months) (log rank, P=0.6). CONCLUSIONS CB-A ablation showed equal efficacy and outcome between SF and BF strategy.