The electrophysiology-guided noninvasive cardiac radioablation, also known as STAR (stereotactic arrhythmia radioablation) is an emerging treatment method for persistent ventricular tachycardia. Since its first application in 2012 in Stanford Cancer Institute, and a year later in University Hospital Ostrava, Czech Republic, the authors from all around the world have published case reports and case series, and several prospective trials were established. In this article, we would like to discuss the available clinical evidence, analyze the potentially clinically relevant differences in methodology, and address some of the unique challenges that come with this treatment method.

• Publikační typ
• časopisecké články MeSH
• přehledy MeSH

BACKGROUND: A percutaneous intravascular cardioverter-defibrillator (PICD) has been developed with a right ventricular (RV) single-coil lead and titanium electrodes in the superior vena cava (SVC)-brachiocephalic vein (BCV) region and the inferior vena cava (IVC). OBJECTIVE: To compare defibrillation thresholds (DFTs) of the PICD with those of a conventional ICD in humans. METHODS: Ten patients with ischemic cardiomyopathy and ejection fraction ≤35% were randomized to initial testing with either PICD or conventional ICD. A standard dual-coil lead was positioned in the RV apex. If randomized to PICD, the device was placed into the vasculature such that 1 titanium electrode was positioned in the SVC-BCV region and the second in the IVC. For PICD DFTs, the RV coil of the conventional ICD lead was connected to the PICD mandrel [shock vector: RV (+) to SVC-BCV (-) + IVC (-)]. When testing the conventional ICD, a subcutaneous pocket was formed in the left pectoralis region and the ICD was connected to the lead system and positioned in the pocket [shock vector: RV (+) to SVC (-) + active can (-)]. Each device was removed before testing with the other. A step-down binary search protocol determined the DFT, with the initial shock being 9 J. RESULTS: The mean PICD DFT was 7.6 ± 3.3 J, and the conventional ICD system demonstrated a mean DFT of 9.5 ± 4.7 J (N = 10; paired t test, P = .28). CONCLUSION: The intravascular defibrillator has DFTs similar to those of commercially available ICDs.

• MeSH
• defibrilátory implantabilní * MeSH
• design vybavení MeSH
• kardiomyopatie terapie   MeSH
• lidé středního věku MeSH
• lidé MeSH
• senioři MeSH
• srdeční komory MeSH
• tepový objem MeSH
• Check Tag
• lidé středního věku MeSH
• lidé MeSH
• mužské pohlaví MeSH
• senioři MeSH
• ženské pohlaví MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• srovnávací studie MeSH

• MeSH
• fibrilace komor MeSH
• komorová tachykardie * chirurgie   MeSH
• lidé MeSH
• srdeční arytmie MeSH
• zobrazování trojrozměrné MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH

Background: Stereotactic Arrhythmia Radioablation (STAR) is an emerging treatment modality for patients with sustained ventricular tachycardia (VT) and refractory to treatment with drugs and radiofrequency catheter ablation (RFA). It is believed that up to 12-17% of patients experience recurrence of VT within 1 year of follow-up; thus, novel therapeutic options are needed. The aim of this article is to present initial experience within a novel treatment modality for VT. Case Summary: Two patients with a medical history of coronary artery disease and heart failure with reduced left ventricle (LV) ejection fraction, after implantation of cardioverter-defibrillator (ICD) and previous unsuccessful RFAs owing to sustained VT were admitted to the cardiology department due to recurrence of sustained VT episodes. With electroanatomical mapping (EAM), the VT substrate in LV has been confirmed and specified. In order to determine the target volume for radioablation, contrast-enhanced computed tomography was performed and the arrhythmia substrate was contoured using EAM data. Using the Volumetric Modulated Arc Therapy technique and three 6 MeV flattening filter-free photon beam fields, a single dose of 25 Gy was delivered to the target volume structure located in the apex and anterior apical segments of LV in the first patient and in the apex, anterolateral and inferior apical segments of the second patient. In both cases, volumes of the target structures were comparable. Interrogation of the implanted ICD at follow-up visits throughout 6 months after the treatment revealed no VT episodes in the first patient and sudden periprocedural increase in VT burden with a subsequent gradual decrease of ventricular arrhythmia to only two non-sustained episodes at the end of the follow-up period in case of the second patient. A significant reduction in premature ventricular contractions burden was observed compared to the pre-treatment period. No noticeable deterioration in LV function was noted, nor any adverse effects of radiosurgery associated with the implanted device. Conclusion: The early response to STAR can be unpredictable and probably does not reflect the final outcome of irradiation. Close monitoring of patients, especially in the early period after irradiation is crucial to properly handle potentially harmful early reactions to STAR.

• Publikační typ
• časopisecké články MeSH

Cardiac stereotactic body radiotherapy is an emerging treatment method for recurrent ventricular tachycardia refractory to invasive treatment methods. The single-fraction delivery of 25 Gy was assumed to produce fibrosis, similar to a post-radiofrequency ablation scar. However, the dynamics of clinical response and recent preclinical findings suggest a possible different mechanism. The data on histopathological presentation of post-radiotherapy hearts is scarce, and the authors provide significantly different conclusions. In this article, we present unique data on histopathological examination of a heart explanted from a patient who had a persistent anti-arrhythmic response that lasted almost a year, until a heart failure exacerbation caused a necessity of a heart transplant. Despite a complete treatment response, there was no homogenous transmural fibrosis in the irradiated region, and the overall presentation of the heart was similar to other transplanted hearts of patients with advanced heart failure. In conclusion, our findings support the theorem of functional changes as a source of the anti-arrhythmic mechanism of radiotherapy and show that durable treatment response can be achieved in absence of transmural fibrosis of the irradiated myocardium.

• Publikační typ
• časopisecké články MeSH