Esophageal safety in CLOSE-guided 50W high-power-short-duration pulmonary vein isolation - The PREHEAT-PVI-Registry

AIMS

Pulmonary vein isolation (PVI) using high-power-short-duration (HPSD) radiofrequency ablation (RF) is emerging as the standard of care for treatment of atrial fibrillation (AF). While procedural short-term to mid-term efficacy and efficiency are very promising, this registry aims to investigate esopahgeal safety using an optimized ablation approach.

METHODS

In a single-centre experience, 388 consecutive standardized first-time AF ablation were performed using a CLOSE-guided-fixed-50W-circumferential PVI and substrate modification without intraprocedural oesophageal temperature measurement. 300 patients underwent post-procedural esophageal endoscopy to diagnose and grade endoscopically detected esophageal lesions (EDEL) and were included in the analysis.

RESULTS

EDEL were detected in 35 of 300 patients (11.6%), 25 of 35 were low-grade KCC 1 lesions with fast healing tendencies. 6 patients suffered KCC 2a lesions, 4 patients had KCC 2b lesions (1.3% of all patients). No esophageal perforation or fistula formation was observed. Patient baseline characteristics, especially patients age, gender and body-mass-index did not influence EDEL incidence. Additional posterior box isolation did not increase the incidence of EDEL. In patients diagnosed with EDEL, mean catheter contact force during posterior wall ablation was higher (11.9 ± 1.8 vs. 14.7 ± 3 grams, p<0.001), mean RF duration was shorter (11.9 ± 1 vs. 10.7 ± 1.2 sec., p<0.001), while achieved AI was not different between groups (434 ± 4.9 vs. 433 ± 9.5, n.s.).

CONCLUSIONS

Incidence of EDEL after CLOSE-guided-50W-HPSD PVI is lower compared to historical cohorts using standard-power RF settings. Catheter contact force during posterior HPSD ablation should not exceed 15 grams. This article is protected by copyright. All rights reserved.

Reconnection patterns after high-power-short-duration pulmonary vein isolation Reconnection patterns after CLOSE-guided 50W high-power-short-duration circumferential pulmonary vein isolation and substrate modification - PV reconnection might no longer be an issue

INTRODUCTION

Ablation of atrial fibrillation (AF) with high-power-short-duration (HPSD) radiofrequency (RF) technology is emerging as a new standard of care in many electrophysiology laboratories. While procedural short-term efficacy and efficiency is very promising, little is known about mid- to long-term effects of HPSD ablation for pulmonary vein isolation and left atrial substrate modification.

METHODS AND RESULTS

In a single-centre registry, 412 AF procedures were performed in 400 individual patients using a standardized CLOSE protocol guided fixed 50W HPSD ablation, aiming for an ablation index (AI) of 400 on the posterior and 550 on the anterior wall. Additional substrate-tailored lines were performed when required. After a mean clinical follow-up of 337 ± 134 days, 15 patients suffered from AF recurrence beyond the blinding period. 12 gave consent to the indicated re-ablation. Here, 11 of 12 patients had chronic isolation of all 4 pulmonary veins (PV). In 3 of 6 patients, a reconnection of additional left atrial ablation lines was revealed. 10 out of 12 patients showed progressive fibrous atrial cardiomyopathy and required additional left atrial substrate modification or re-isolation of left-atrial lines. During the follow-up no clinical case of atrioesophageal fistula was registered. No PV stenosis after initial HPSD PVI was documented.

CONCLUSIONS

Patients requiring re-ablation of AF or other atrial tachycardia after a fixed 50W HPSD circumferential PVI and substrate modification predominantly suffer from progressive fibrous atrial cardiomyopathy, while PV reconnection appears to be a rare cause of AF recurrence. This article is protected by copyright. All rights reserved.

P3711Impact of peri-device leakage after interventional occlusion of the left atrial appendage: Results from the ORIGINAL registry (saxOnian RegIstry analyzinG and followINg left atrial Appendage cLosure)

Background

Oral anticoagulation for prophylaxis of central and peripheral embolisation is limited in its use in patients with atrial fibrillation (AF) and bleeding events. As an alternative to anticoagulation, the interventional closure of the left atrial appendage (LAAO) is available. A common clinical dilemma is the treatment of patients with potential peri-device leakage following LAA occlusion. The specific definition of the severity of the leak and the long-term clinical implications have not yet been sufficiently investigated.

Methods

The multi-centre ORIGINAL registry was initiated 2014. The aim of this registry is to analyze the safety and efficacy of the procedure in patients with a high risk of bleeding in everyday clinical practice and to evaluate hemorrhagic and thromboemb. events in the long term follow-up. Patients with an indication for LAA occl. were included in the registry after informed consent. The impl., follow-up and anticoagulation regimens are performed according to the standard of the participating centers. 521 patients with AF underwent an implantation of an LAA closure device between Jul. 2014 and Nov. 2018. A mean follow-up of 463 days could be reached in 386 patients.

Results

The periprocedural complication rate was 3.8% of which 5 patients experienced pericardial effusion (successful treatment with pericardial puncture or surgical), 2 patients had periprocedural stroke and 1 patient suffered from air embolism. In 27 patients a peri-device flow due to incomplete occlusion was detected by TEE (5.4% of the implantations). The size ranged between 1 and 8 mm (mean 2.28 mm (SD=2.11)). The eccentricity index (EI) of the LAA in these patients was 1.22 (SD 0.17), and thus the LAA rather oval, while those LAA without leakage tend to be more circular (EI 1.08 with SD=0.17). 2 of the patients with leakage (7.4%) experienced stroke or peripheral embolism, respectively. The annual risk for stroke/TIA/peripheral embolism of these patients was 5.84%, the annual risk of the patients without leakage was 2.04%. Patients with a leakage >6 mm were treated with rivaroxaban in full therapeutic dosage. One patient underwent an additional procedure.

Conclusion

The evaluation and management of para-device leakage after an interventional LAA occlusion represents a challenge. Currently, limited data are available on the optimal strategy. Those data indicate that residual peri-device flow into the LAA after percutaneous closure with the Watchman device represents no cause for alarm. However, our data suggest, that patients with peridevice leak might be at a higher risk of thromboembolic events. Furthermore, it could be shown, that these patients had rather oval ostium of the LAA, while those LAA without leakage tend to be more circular. This implicates the importance of advanced imaging methods, such as 3D-TEE, which are capable to precisely determine the size of the LAA and the degree of its circularity.

Acknowledgement/Funding

None

284Outcomes after left atrial appendage occlusion with AMPLATZER Amulet and WATCHMAN device: Results from the ORIGINAL registry (saxOnian RegIstry analyzinG and followINg left atrial Appendage cLosure)

Aims

Left atrial appendage occlusion (LAAO) is a therapeutic option for patients with non-valvular atrial fibrillation (NVAF) and high risk of bleeding. This study reports outcomes of patients enrolled in the prospective multicentre, investigator initiated real life registry in the Free State of Saxony (saxOnian RegIstry analyzinG and followINg left atrial Appendage cLosure).

Methods and results

Data of all consecutive 521 patients (64.7% adult males, 35.3% adult females, mean age: 75.1 (SD 7.9) years with non-valvular atrial fibrillation undergoing interventional left atrial appendage occlusion procedure in the ORIGINAL prospective registry were analysed. The CHA2DS2-VASc and HAS-BLED scores were 4.3 (SD 1.5) and 3.7 (SD 1.1), respectively. 78.9% of the patients had a history of bleeding. 89.3% of the patients were considered as non-eligible for long term oral anticoagulation. A left atrial appendage occlusion device was successfully implanted in 97.5% of cases. A mean follow-up of 463 days could be reached in 386 patients. Among these, the distribution of the follow-up length reached was as follows: 1 year 205, 2 years 118, 3 years 65 and 4 years 17 patients. In the follow-up the annual frequency of stroke was very low (0.4%), which resulted in the 4.98% absolute risk reduction in the amount of thromboembolic strokes, which would have been expected according to the calculated CHA2DS2-VASc score in the hypothetic group not receiving any anticoagulant therapy. The occurrence of major and minor bleeding in the follow-up was 1.55% and 3.37% respectively.

Conclusions

In this prospective multicentre study we included the patients who are at high risk of stroke and bleeding. The annual ischemic stroke rate was 0.4%, the LAA could be sealed in 97.5%. Six months after the LAA closure only 3.63% of all patients were further on treated using oral anticoagulation. Considering the stroke reduction rates, the implantation of an LAAO device proves to be effective and safe in the clinical routine in the studied population.

Acknowledgement/Funding

None

Intra-aortic balloon pump (IABP) counterpulsation improves cerebral perfusion in patients with decreased left ventricular function

Background:

The current goal of treatment after acute ischemic stroke is the increase of cerebral blood flow (CBF) in ischemic brain tissue. Intra-aortic balloon pump (IABP) counterpulsation in the setting of cardiogenic shock is able to reduce left ventricular afterload and increase coronary blood flow. The effects of an IABP on CBF have not been sufficiently examined. We hypothesize that the use of an IABP especially enhances cerebral blood flow in patients with pre-existing heart failure.

Methods:

In this pilot study, 36 subjects were examined to investigate the effect of an IABP on middle cerebral artery (MCA) transcranial Doppler (TCD) flow velocity change and relative CBF augmentation by determining velocity time integral changes (ΔVTI) in a constant caliber of the MCA compared to a baseline measurement without an IABP. Subjects were divided into two groups according to their left ventricular ejection fraction (LVEF): Group 1 LVEF >30% and Group 2 LVEF ≤30%.

Results:

Both groups showed an increase in CBF using an IABP. Patients with a LVEF ≤30% showed a significantly higher increase of ΔVTI in the MCA under IABP augmentation compared to patients with a LVEF >30% (20.9% ± 3.9% Group 2 vs.10.5% ± 2.2% Group 1, p<0,05). The mean arterial pressure (MAP) increased only marginally in both groups under IABP augmentation.

Conclusions:

IABP improves cerebral blood flow, particularly in patients with pre-existing heart failure and highly impaired LVEF. Hence, an IABP might be a treatment option to improve cerebral perfusion in selected patients with cerebral misperfusion and simultaneously existing severe heart failure.

Implantable cardioverter defibrillator lead implantation in patients with a persistent left superior vena cava--feasibility, chances, and limitations: representative cases in adults

AIMS

Device implantation may be challenging in patients with venous abnormalities. The most common congenital variation--frequently associated with other congenital abnormalities--is described as persistent left superior vena cava (PLSVC).

METHODS AND RESULTS

The present case series demonstrates successful implantable cardioverter defibrillator (ICD) lead implantation in the most common anatomic variations of PLSVC. All types of current ICD models (single and dual chamber, VDD, and cardiac resynchronization therapy devices) were used. Angiographic findings and implantation techniques (e.g. guiding and diagnostic catheters, wires, occlusion balloons, and rotation sequences) are presented in images and movie sequences.

CONCLUSION

Device implantation in patients with PLSVC may be complex but a successful transvenous approach is possible in most of the cases. Careful imaging prior to implantation procedure is essential for understanding the individual anatomy and in order to choose adequate material and implantation strategy.

Apoptosis of human macrophages by Flt-4 signaling: implications for atherosclerotic plaque pathology

BACKGROUND

Neointimal inflammation and angiogenesis are important contributors of progression and destabilization of the atherosclerotic plaque. While the role of vascular endothelial growth factor (VEGF) and its receptors VEGF-R1 (Flt-1) and VEGF-R2 (Flk-1) in this process has clearly been defined, expression of the VEGF-R3 (Flt-4) has only been documented on lymphatic and tumor endothelium. This study examined Flt-4 expression in human atherosclerotic plaque and explored its implications for atherosclerotic disease.

METHODS AND RESULTS

Carotid artery thrombendartherectomy specimens from 10 patients with unstable plaque were stained for Flt-4 and its specific growth factors VEGF-C and VEGF-D. Microvascular endothelial cells (MVEC) stained positive for VEGF-C and -D, but not for Flt-4. Interestingly, macrophages within inflammatory perivascular regions coexpressed Flt-4, VEGF-C and VEGF-D. In vitro studies confirmed the expression of Flt-4, VEGF-C and VEGF-D in human monocytes and cultured macrophages. Treatment of macrophages with VEGF-D induced apoptosis as determined by annexin V staining, by immunoblotting of activated caspase 3, and by the ratio of Bcl-2/Bax as well as by DNA fragmentation. Immunohistochemical studies of advanced human carotid atherosclerotic plaque confirmed the coexpression of Flt-4 with activated caspase 3 and TUNEL staining in macrophages, indicating an ongoing apoptotic process.

CONCLUSION

Human monocytes/macrophages express VEGF-C and -D and their receptor Flt-4 in vitro and in vivo within advanced atherosclerotic lesions. Flt-4, in turn, mediates monocyte/macrophage apoptosis and may this way alter plaque stability.

Effect of peri-operative diltiazem on myocardial ischaemia and function in patients receiving mammary artery grafts

A prospective, randomized study was performed with 66 patients undergoing elective coronary bypass surgery involving internal mammary artery (IMA) grafts to the left anterior descending artery (LAD). Patients received a continuous peri-operative infusion of either diltiazem (0.1 mg.kg-1 h-1, n = 32) or nitroglycerin (1 microgram.kg-1 min-1, n = 34) for 24 h. The aim of this study was to define the effect of the calcium channel blocker diltiazem on peri-operative ischaemia, arrhythmias and myocardial function in patients receiving arterial bypass grafts by preventing transient vasospasm. The study patients did not differ with respect to pre-operative, operative and haemodynamic data. Patients treated with diltiazem had lower numbers of ventricular premature beats/hour (8.1 +/- 7.8 vs 20.5 +/- 11.2; P < 0.05). The anti-ischaemic efficacy of peri-operative diltiazem in patients receiving IMA grafts significantly reduced the incidence and duration of transient ischaemic events (0 vs 5). Additionally, patients receiving IMA grafts and diltiazem showed significantly lower peak levels of ischaemia-sensitive laboratory parameters, as compared to IMA graft patients receiving only nitroglycerin: CK-MB: 17.3 +/- 7.7 vs 23.5 +/- 11.0, (P < 0.05); MB-M: 29.4 +/- 14.7 vs 43.1 +/- 27.4, (P < 0.05); troponin-T: 0.88 +/- 0.6 vs 1.41 +/- 0.9, (P < 0.05).(ABSTRACT TRUNCATED AT 250 WORDS)

Effects of diltiazem on perioperative ischemia, arrhythmias, and myocardial function in patients undergoing elective coronary bypass grafting

A prospective, randomized study was performed on 120 patients undergoing elective coronary bypass grafting to define the effect of the calcium channel blocker diltiazem on perioperative ischemia, arrhythmias, and myocardial function. Patients received a continuous 24-hour perioperative infusion of either diltiazem (0.1 mg/kg per hour, n = 60) or nitroglycerin (1 micrograms/kg per minute, n = 60). Perioperative monitoring included hemodynamic measurements, three-channel Holter monitoring, repeated assessment of 12-lead electrocardiograms, and analysis of ischemia-specific laboratory parameters (creatine kinase, creatine kinase-MB, and creatine kinase-MB-mass and troponin-T). Global and regional systolic function and diastolic compliance were assessed by means of transesophageal echocardiography. The two groups did not differ with respect to preoperative and operative data. Except for a significant reduction in perioperative heart rate, diltiazem had no influence on hemodynamic parameters. The number (17 +/- 9 versus 25 +/- 5, p < 0.05) and the duration (69 +/- 47 versus 104 +/- 87 minutes, p < 0.05) of transient ischemic events were significantly reduced as compared with the nitroglycerin group. In addition, peak values of all assessed laboratory parameters except creatine kinase were significantly lower in the diltiazem group. Patients treated with diltiazem had a lower incidence of perioperative atrial fibrillation (5% versus 18%, p < 0.05) and lower numbers of ventricular premature beats per hour (10 +/- 8 versus 19 +/- 22, p < 0.05) and ventricular runs per hour (5 +/- 17 versus 32 +/- 38, p < 0.05). Postoperatively, the percent fractional area of contraction and percent systolic wall thickening of the anterior wall were significantly improved in the diltiazem group but not in the nitroglycerin group. In addition, the postoperative diastolic flow/velocity ratio was significantly lower in the nitroglycerin group than in the diltiazem group (0.949 +/- 0.391 versus 1.331 +/- 0.475, p < 0.001). It is concluded that perioperative infusion of the calcium antagonist diltiazem has no adverse effect on perioperative hemodynamics and systolic myocardial function and provides potent anti-ischemic and antiarrhythmic protection in patients undergoing coronary bypass grafting.