Georg Nölker

Incidence of oesophageal wall injury post-pulmonary vein antrum isolation for treatment of patients with atrial fibrillation

AIMS Oesophageal injury has been reported with delivery of radio-frequency lesions at the left atrium posterior wall in catheter ablation procedures for atrial fibrillation (AF). In this observational study we prospectively assessed endoscopical oesophageal wall changes after pulmonary vein antrum isolation (PVAI) in patients presenting for treatment of AF. METHODS AND RESULTS Twenty eight patients (18 men; mean age 55 +/- 11 years) were ablated using either a cooled-tip or an 8 mm tip ablation catheter. Endoscopy of the oesophagus was performed 24 h after PVAI. If oesophageal wall changes were detected post ablation, a proton-pump inhibitor (PPI) was started and repeat endoscopy was considered. Within 24 h post ablation oesophageal wall changes were confirmed in 47% of our study patients. Erythema was identified in 29% and necrotic or ulcer-like changes in 18% of patients. None of study patients experienced left atrial-oesophageal fistula. A significant correlation between Reflux-like symptoms and oesophageal wall changes was demonstrated. Complete recovery of oesophageal lesions was shown in all study patients 2-4 weeks post ablation. CONCLUSION A significant number of patients experienced oesophageal wall injury post PVAI. Initiating PPIs in this group of patients might facilitate recovery of oesophageal wall injuries caused by radio-frequency energy delivery.

Three-dimensional left atrial and esophagus reconstruction using cardiac C-arm computed tomography with image integration into fluoroscopic views for ablation of atrial fibrillation: Accuracy of a novel modality in comparison with multislice computed tomography

BACKGROUND Visualization of the left atrium (LA) and pulmonary veins (PVs) is crucial in PV isolation (PVI). Additional delineation of the esophagus might avoid severe side effects. Cardiac C-arm computed tomography (DynaCT Cardiac, Siemens AG, Forchheim, Germany) has been introduced as a novel intraprocedural imaging modality based on a rotational angiography. OBJECTIVES The purpose of this study was to prove the quantitative accuracy of DynaCT Cardiac as compared with multislice CT (MSCT) in imaging of the LA and PV in patients undergoing PVI. METHODS Thirty-four consecutive patients (22 male, age 64 +/- 12 years) with symptomatic atrial fibrillation (AF) and indication for PVI were studied. Diameters of the PV, the LA appendage (LAA), and the descending aorta were measured, and the position of the esophagus was defined using preprocedural MSCT and intraprocedural DynaCT Cardiac. RESULTS There was a significant correlation between both measurements for diameters of the LAA (r = 0.86, P <.05), PV (r = 0.98, P <.05), and the descending aorta (r = 0.98, P <.05). The overall correlation of vessel diameters was r = 0.99. The LA volumes correlation was r = 0.86 and P <.05. A significant difference of the esophageal position was found between preprocedural MSCT and intraprocedural DynaCT Cardiac (r = 0.53, P <.05). CONCLUSIONS DynaCT Cardiac is a novel intraprocedural rotational angiographic technique. It is highly accurate in displaying crucial structures for PVI in comparison with the results of MSCT. Therefore, DynaCT Cardiac can be used as an alternative imaging technique to improve PVI accuracy.

Treatment of Cheyne-Stokes Respiration Reduces Arrhythmic Events in Chronic Heart Failure

This study aimed to investigate whether adequate treatment of Cheyne‐Stokes respiration (CSR) reduces the risk of arrhythmic events in patients with chronic heart failure (CHF).

Cryoballoon Pulmonary Vein Isolation Supported by Intracardiac Echocardiography: Integration of a Nonfluoroscopic Imaging Technique in Atrial Fibrillation Ablation

Intracardiac Echo Supported Cryoballoon Ablation. Introduction: Cryoballoon ablation has been adopted for pulmonary vein (PV) isolation (PVI) in many centers. Complete occlusion of PV by an adequately sized balloon is crucial for effectiveness of cryoenergy delivery. The aim of this study was to evaluate intracardiac echocardiography (ICE) as an alternative imaging technique compared to angiographic imaging in cryoballoon PVI.

Image-integration of intraprocedural rotational angiography-based 3D reconstructions of left atrium and pulmonary veins into electroanatomical mapping: accuracy of a novel modality in atrial fibrillation ablation.

DynaCT Cardiac Integration into Electroanatomical Mapping.  Introduction: Exact visualization of complex left atrial (LA) anatomy is crucial for safety and success rates when performing catheter ablation of atrial fibrillation (AF). The aim of our study was to validate the accuracy of integrating rotational angiography‐based 3‐dimensional (3D) reconstructions of LA and pulmonary vein (PV) anatomy into an electroanatomical mapping (EAM) system.

Apixaban in patients at risk of stroke undergoing atrial fibrillation ablation

Abstract Aims It is recommended to perform atrial fibrillation ablation with continuous anticoagulation. Continuous apixaban has not been tested. Methods and results We compared continuous apixaban (5 mg b.i.d.) to vitamin K antagonists (VKA, international normalized ratio 2–3) in atrial fibrillation patients at risk of stroke a prospective, open, multi-centre study with blinded outcome assessment. Primary outcome was a composite of death, stroke, or bleeding (Bleeding Academic Research Consortium 2–5). A high-resolution brain magnetic resonance imaging (MRI) sub-study quantified acute brain lesions. Cognitive function was assessed by Montreal Cognitive Assessment (MoCA) at baseline and at end of follow-up. Overall, 674 patients (median age 64 years, 33% female, 42% non-paroxysmal atrial fibrillation, 49 sites) were randomized; 633 received study drug and underwent ablation; 335 undertook MRI (25 sites, 323 analysable scans). The primary outcome was observed in 22/318 patients randomized to apixaban, and in 23/315 randomized to VKA {difference −0.38% [90% confidence interval (CI) −4.0%, 3.3%], non-inferiority P = 0.0002 at the pre-specified absolute margin of 0.075}, including 2 (0.3%) deaths, 2 (0.3%) strokes, and 24 (3.8%) ISTH major bleeds. Acute small brain lesions were found in a similar number of patients in each arm [apixaban 44/162 (27.2%); VKA 40/161 (24.8%); P = 0.64]. Cognitive function increased at the end of follow-up (median 1 MoCA unit; P = 0.005) without differences between study groups. Conclusions Continuous apixaban is safe and effective in patients undergoing atrial fibrillation ablation at risk of stroke with respect to bleeding, stroke, and cognitive function. Further research is needed to reduce ablation-related acute brain lesions.

Performance of an Implantable Cardiac Monitor to Detect Atrial Fibrillation: Results of the DETECT AF Study

Reliable detection and monitoring of atrial fibrillation (AF) is essential for accurate clinical decision making, which can now be done continuously with the introduction of implantable cardiac monitors (ICM) The DETECT AF study evaluated the performance of the Confirm DM2102 ICM (St. Jude Medical, St. Paul, MN, USA) to accurately detect and monitor AF.

Three-dimensional coronary sinus reconstruction-guided left ventricular lead implantation based on intraprocedural rotational angiography: a novel imaging modality in cardiac resynchronization device implantation †

AIMS Rotational angiography (RA) of the coronary sinus (CS) provides more anatomical insights compared with static angiographies. We evaluated intraprocedural three-dimensional (3D) CS reconstruction (RC) based on RA, using syngo(®) DynaCT Cardiac to guide CS lead implantation. METHODS AND RESULTS In 24 patients with indication for cardiac resynchronization therapy, intraprocedural RA and 3D RC of the CS was performed. Lead placement was guided by 3D image integration into real-time fluoroscopy. Rotational angiography and 3D RCs were evaluated regarding visibility of the CS and tributaries, CS-to-target vein angles, and vessel diameters. The target vein for CS lead implantation, identified by RA, was successfully displayed by 3D RC in 20 (91%) of 22 patients with adequate RA. All lead implantations were guided successfully by 3D image integration into real-time fluoroscopy. Cranial or caudal angulations were used in 95% of the procedures without further angiographies. Rotational angiography displayed a mean of 2.9 ± 1.0 second-order side branches compared with 1.8 ± 1.1 in 3D RCs (P< 0.05). The CS-to-target vein angle estimated from static projections (right anterior oblique 20°, left anterior oblique 40°, and even optimal RA view) differed substantially from 3D RCs. Main vessel diameters did not differ significantly between both techniques. CONCLUSION Intraprocedural 3D RC of the CS and 3D image integration-guided lead placement is feasible. Coronary sinus-to-target vein angles seemed to be misestimated even by RA views compared with 3D RC. Thus RA and 3D CS RC should be applied routinely for CS lead implantation.

Intracardiac echocardiography for registration of rotational angiography-based left atrial reconstructions: a novel approach integrating two intraprocedural three-dimensional imaging techniques in atrial fibrillation ablation

AIMS Image integration of three-dimensional (3D) reconstructions of left atrial (LA) and pulmonary vein (PV) anatomy into electroanatomical mapping (EAM) plays a major role in atrial fibrillation (AF) ablation. Point-by-point EAM is commonly used for registration of imported LA and PV anatomy. We aimed to assess the accuracy of intraprocedural rotational angiography-based LA imaging registered by spatial reconstruction of intracardiac echocardiography (ICE) in patients undergoing AF ablation. METHODS AND RESULTS Twenty-two patients (11 males, 66 ± 12 years) were studied. Reconstructions of LA and PVs based on rotational angiography were registered by a second 3D reconstruction based on ICE. In a second step, EAM points were added to ICE 3D reconstructions. A 3D image of the LA and PVs was reconstructed in all patients by both imaging modalities. Rotational angiography and ICE-based LA 3D reconstructions took 11.5 ± 5.2 and 20.4 ± 11.2 min, respectively. A total of 17 ± 6 two-dimensional ICE fans were used for spatial reconstruction of ICE. The deviation between the two 3D shells was 2.6 ± 0.5 mm. Integration of 78 ± 58 EAM points into ICE 3D reconstruction did not significantly reduce the deviation to rotational angiography-based reconstructions (2.7 ± 0.6 mm). All PVs were isolated successfully. CONCLUSIONS Intraprocedural 3D reconstruction of LA and PVs for ablation of AF is feasible based on both rotational angiography and ICE. LA reconstructions based on rotational angiography can accurately be registered using 3D ICE shells. Additional EAM does not enhance accuracy. Therefore, registration of rotational angiography-based 3D reconstructions by 3D reconstructions from ICE seems to be an alternative technique to support AF ablation.

Reliability and accuracy of sleep apnea scans in novel cardiac resynchronization therapy devices: an independent report of two cases

Pacemaker apnea scan algorithms are able to screen for sleep apnea. We investigated whether these systems were able to accurately detect sleep-disordered breathing (SDB) in two patients from an outpatient clinic. The first patient suffered from ischemic heart failure and severe central sleep apnea (CSA) and underwent adaptive servoventilation therapy (ASV). The second patient suffered from dilated cardiomyopathy and moderate obstructive sleep apnea (OSA). Pacemaker read-outs did not match polysomnography (PSG) recordings well and overestimated the apnea–hypopnea index. However, ASV therapy-induced SDB improvements were adequately recognized by the apnea scan of the Boston Scientific INVIVE® cardiac resynchronization therapy pacemaker. Detection of obstructive respiratory events using impedance-based technology may underestimate the number of events, as frustrane breathing efforts induce impedance changes without significant airflow. By contrast, in the second case, apnea scan overestimated the number of total events and of obstructive events, perhaps owing to a very sensitive but less specific hypopnea definition and detection within the diagnostic algorithm of the device. These two cases show that a pacemaker apnea scan is able to reflect SDB, but PSG precision is not met by far. The device scan revealed the decline of SDB through ASV therapy for CSA in one patient, but not for OSA in the second case. To achieve reliable monitoring of SDB, further technical developments and clinical studies are necessary.ZusammenfassungSchrittmacher-Apnoescan-Algorithmen können zum Apnoe-Screening genutzt werden. Wir untersuchten, ob diese Systeme zuverlässig für die Erkennung schlafbezogener Atemstörungen sind bei 2 Patienten unserer Ambulanz. Der erste Patient hatte eine ischämische Kardiomyopathie, schwere zentrale Schlafapnoe (ZSA) und erhielt eine adaptive Servoventilationstherapie (ASV). Der zweite Patient hatte eine dilatative Kardiomyopathie und ein mittelgradiges obstruktives Schlafapnoe-Syndrom (OSAS). Die Schrittmacher-Ausdrucke korrelierten nicht gut mit der Polysomnographie (PSG) und überschätzten den Apnoe-Hypopnoe-Index (AHI). ASV-Therapie-induzierte Verbesserungen der Schlafapnoe wurden jedoch adäquat durch den Apnoe-Scan des CRT-Schrittmachers erkannt. Die Anzahl obstruktiver Atemereignisse kann durch Impedanz-messende Algorithmen unterschätzt werden, da frustrane Atemmanöver Impedanzänderungen verursachen ohne signifikanten Luftstrom. Auf der anderen Seite zeigt der 2. Fall, dass der Apnoe-Scan die Anzahl aller Ereignisse und aller obstruktiven Ereignisse überschätzen kann, am ehesten aufgrund einer zu sensitiven und zu unspezifischen Definition der Hypopnoe und -Detektion in diesem diagnostischen Device-Algorithmus. Diese 2 Fälle zeigen, dass Schrittmacher Apnoe-Scans in der Lage sind, schlafbezogene Atemstörungen zu erkennen, jedoch mit einer Präzision weit unter der Polysomnographie. Der Device-Scan erkannte die Abnahme der Schlafapnoe durch ASV-Therapie bei ZSA bei einem Patienten, jedoch nicht für OSAS im zweiten Fall. Um Schlafapnoe zuverlässig monitoren zu können, sind weitere technische Verbesserungen und klinische Studien notwendig.