Histopathological Examination of an Explanted Heart in a Long-Term Responder to Cardiac Stereotactic Body Radiotherapy (STereotactic Arrhythmia Radioablation).

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.

The impact of complications related to transvenous lead extraction on the 12-month prognosis: Insights from the SILCARD registry.

BACKGROUND: Scant data exist on long-term outcomes, including death, in patients with complica-tions related to transvenous lead extractions (TLE). AIMS: We sought to characterize the population and examine the outcomes including risk factors for in-hospital complications and 12-month mortality and morbidity related to the complications in a large administrative database of patients undergoing TLE. RESULTS: From the database of patients hospitalized for cardiovascular diseases and included in the Silesian Cardiovascular Database (SILCARD) registry, we selected the admissions of those who underwent TLE according to the appropriate ICD-9 codes. The patients were divided into two groups based on whether they did or did not manifest any complications during their hospitalization for the TLE procedure. Between 2007 and 2019, we found a total of 835 patients who underwent TLE. TLE-related complications occurred in 56 patients (6.7%) of the Complications-Yes group while no complications were recorded in 779 (93.3%) patients of the Complications-No group. A significant difference in the rate of all-cause mortality (23.9% vs. 6.5%; P <0.001) and major adverse cardiac events (MACE) (58.7% vs. 39.4%; P = 0.01) between the Complications-Yes and Complications-No groups were recorded. Multivariable analysis of the entire study population revealed that prior dialysis, chronic kidney disease, and ventricular tachycardia were independent factors of a higher risk of TLE-related in-hospital complications. Multivariable analysis of the patients discharged from the hospital after the TLE procedure showed that TLE-related complications, a history of heart failure, and older age independently affected 12-month mortality. CONCLUSIONS: The presence of TLE-related in-hospital complications increased 12-month mortality.