One-year mortality and causes of death after stereotactic radiation therapy for refractory ventricular arrhythmias: A systematic review and pooled analysis.

Patients treated with cardiac stereotactic body radiation therapy (radioablation) for refractory ventricular arrhythmias are patients with advanced structural heart disease and significant comorbidities. However, data regarding 1-year mortality after the procedure are scarce. This systematic review and pooled analysis aimed at determining 1-year mortality after cardiac radioablation for refractory ventricular arrhythmias and investigating leading causes of death in this population. MEDLINE/EMBASE databases were searched up to January 2023 for studies including patients undergoing cardiac radioablation for the treatment of refractory ventricular arrhythmias. Quality of included trials was assessed using the NIH Tool for Case Series Studies (PROSPERO CRD42022379713). A total of 1,151 references were retrieved and evaluated for relevance. Data were extracted from 16 studies, with a total of 157 patients undergoing cardiac radioablation for refractory ventricular arrhythmias. Pooled 1-year mortality was 32 % (95 %CI: 23-41), with almost half of the deaths occurring within three months after treatment. Among the 157 patients, 46 died within the year following cardiac radioablation. Worsening heart failure appeared to be the leading cause of death (52 %), although non-cardiac mortality remained substantial (41 %) in this population. Age≥70yo was associated with a significantly higher 12-month all-cause mortality (p<0.022). Neither target volume size nor radiotherapy device appeared to be associated with 1-year mortality (p = 0.465 and p = 0.199, respectively). About one-third of patients undergoing cardiac stereotactic body radiation therapy for refractory ventricular arrhythmias die within the first year after the procedure. Worsening heart failure appears to be the leading cause of death in this population.

Cardiac stereotactic radiation therapy for refractory ventricular arrhythmias in patients with left ventricular assist devices.

Left ventricular assist device (LVAD) implantation is an established treatment for patients with advanced heart failure refractory to medical therapy. However, the incidence of ventricular arrhythmias (VAs) is high in this population, both in the acute and delayed phases after implantation. About one-third of patients implanted with an LVAD will experience sustained VAs, predisposing these patients to worse outcomes and complicating patient management. The combination of pre-existing myocardial substrate and complex electrical remodeling after LVAD implantation account for the high incidence of VAs observed in this population. LVAD patients presenting VAs refractory to antiarrhythmic therapy and catheter ablation procedures are not rare. In such patients, treatment options are extremely limited. Stereotactic body radiation therapy (SBRT) is a technique that delivers precise and high doses of radiation to highly defined targets, reducing exposure to adjacent normal tissue. Cardiac SBRT has recently emerged as a promising alternative with a growing number of case series reporting the effectiveness of the technique in reducing the VA burden in patients with arrhythmias refractory to conventional therapies. The safety profile of cardiac SBRT also appears favorable, even though the current clinical experience remains limited. The use of cardiac SBRT for the treatment of refractory VAs in patients implanted with an LVAD are even more scarce. This review summarizes the clinical experience of cardiac SBRT in LVAD patients and describes technical considerations related to the implementation of the SBRT procedure in the presence of an LVAD.

Catheter knot around the mitral valve apparatus: An exceptional complication of remote magnetic navigation.

Remote magnetic navigation (RMN) is as safe and effective as manual navigation for catheter ablation of ventricular arrhythmias. This case is the first description of a soft-tip ablation catheter entrapment in the mitral valve apparatus during an RMN ablation procedure. The tight knot created by the catheter around a mitral valve chordae required surgical removal. This complication, which has never been reported before, highlights the need for closer fluoroscopic monitoring when performing catheter loops inside the ventricles when using the RMN system.

Cardiac stereotactic ablative radiotherapy for refractory ventricular arrhythmias: A radical alternative? A narrative review of rationale and cardiological aspects.

Ventricular arrhythmias are serious life-threatening cardiac disorders. Despite many technological improvements, a non-negligible number of patients present refractory ventricular tachycardias, resistant to a catheter ablation procedure, placing these patients in a therapeutic impasse. Recently, a cardiac stereotactic radioablative technique has been developed to treat patients with refractory ventricular arrhythmias, as a bail out strategy. This new therapeutic option historically brings together two fields of expertise unknown to each other, pointing out the necessity of an optimal partnership between cardiologists and radiation oncologists. As described in this narrative review, the understanding of cardiological aspects of the technique for radiation oncologists and treatment technical aspects comprehension for cardiologists represent a major challenge for the application and the future development of this promising treatment.

Distance between the descending aorta and the left inferior pulmonary vein as a determinant of biophysical parameters during paroxysmal atrial fibrillation cryoablation.

INTRODUCTION: The distance from the descending aorta (DA) to the posterior wall of the left atrium (LA) is variable. We aimed to determine whether the proximity between the DA and the left inferior pulmonary vein (LIPV) ostium has an impact on biophysical parameters and cryoballoon (CB) ablation efficacy during LIPV freezing. METHODS: Patients referred for CB-ablation of atrial fibrillation (AF) in two high-volume centers were included. Cryoablation data were collected prospectively for each patient. The anatomical relationships between the LIPV and the DA (distance LIPV ostium-DA, presence of an aortic imprint on the posterior aspect of the LIPV) were then retrospectively analysed on the LA computed tomography scans realized before AF ablation. RESULTS: A total of 350 patients were included (70% men, 59.7 ± 11.5 years). The decrease in the Ostium-DA distance was significantly correlated to the increase in the time-to-isolation (TTI) (r = -.31; p = .036), with less negative temperature (r = -.11; p = .045). Similarly, the presence of an aortic imprint on the LIPV was associated with a longer TTI (p < .001). The analysis of redo procedures data shows a trend toward the presence of shorter ostium-DA distances (15.3 ± 3.29 vs. 18.1 ± 4.99, p = .15) and more frequent aortic imprints (63.6% vs. 47.5%, p = .34) in patients with LIPV reconnection as opposed to patients without reconnection in the LIPV. CONCLUSION: Our findings indicated that the DA seems to have a "radiator" effect influencing LIPV cryoablation parameters during CB-ablation. Additional studies will be needed to elucidate whether this biophysical influence has a clinical impact in LIPVs reconnections.

Impact of Midregional N-Terminal Pro-Atrial Natriuretic Peptide and Soluble Suppression of Tumorigenicity 2 Levels on Heart Rhythm in Patients Treated With Catheter Ablation for Atrial Fibrillation: The Biorhythm Study.

Background We assessed the impact of preprocedural plasma levels of MRproANP (midregional N-terminal pro-atrial natriuretic peptide) and sST2 (soluble suppression of tumorigenicity 2) on recurrence of atrial fibrillation (AF) at 1 year after catheter ablation of AF. Methods and Results This was a prospective, multicenter, observational study including patients undergoing catheter ablation of AF. MRproANP and sST2 were measured in a peripheral venous blood preprocedure, and MRproANP was assessed in the right and left atrial blood during ablation. The primary end point was recurrent AF between 3 and 12 months postablation, defined as a documented (>30 seconds) episode of AF, flutter, or atrial tachycardia. We included 106 patients from December 2017 to March 2019; 105 had complete follow-up, and the mean age was 63 years with 74.2% males. Overall, 34 patients (32.1%) had recurrent AF. In peripheral venous blood, MRproANP was significantly higher in patients with recurrent AF (median, 192.2; [quartile 1-quartile 3, 155.9-263.9] versus 97.1 [60.9-150.7] pmol/L; P<0.0001), as was sST2 (median, 30.3 [quartile 1-quartile 3, 23.3-39.3] versus 23.4 [95% CI, 17.4-33.0] ng/mL; P=0.0033). In the atria, MRproANP was significantly higher than in peripheral blood and was higher during AF than during sinus rhythm. Receiver operating characteristic curve analysis identified a threshold of MRproANP>107.9 pmol/L to predict AF recurrence at 1 year and a threshold of >26.7 ng/mL for sST2. By multivariate analysis, MRproANP>107.9 pmol/L was the only independent predictor of recurrent AF (OR, 24.27; 95% CI, 4.23-139.18). MRproANP<107.9 pmol/L identified subjects at very low risk of recurrence (negative predictive value >95%). Conclusions Elevated MRproANP level independently predicts recurrent AF, whereas sST2 levels do not appear to have any prognostic value in assessing the risk of recurrence of AF up to 1 year after catheter ablation. Registration URL: https://www.clinicaltrials.gov; Unique identifier: NCT03351816.