Optimal ablation index parameters for radiofrequency ablation therapy of atrial fibrillation

Objective: To explore the optimal ablation index (AI) parameters for radiofrequency catheter ablation (RA) for treating atrial fibrillation (AF). Method: Patients with AF (186) who underwent bilateral PVAI in the Department of Cardiology, Zhuhai People’s Hospital, Guangdong Province, from March 2018 to October 2019 and received catheter ablation as first-round treatment, were grouped according to the received AI. Control group included patients (95) who received the recommended AI ablation (350–400 for posterior wall, 400–450 for non-posterior wall). Patients in optimal AI group were ablated with optimal AI (300–330 for posterior wall, 350–380 for non-posterior wall). Results: Of 186 patients, 66 patients had paroxysmal atrial fibrillation and a mean CHA2DS2-VASc score of 2.83±1.64. Isolation rates of bilateral PVI in both groups were 91.4% and 93.6%, for patients with paroxysmal atrial fibrillation, and 81.7% and 80% for patients with persistent atrial fibrillation (P > 0.05). Left atrial function index (LAFI) decreased under the condition of sinus rhythm at the 3rd and 6th months (P < 0.05). LAFI improvement was significantly better in the optimal AI group than in the control group (P < 0.05). Rates of pain and cough during the ablation, and postoperative gastrointestinal discomfort and use of PPIs were higher in the control group (P < 0.05). Conclusion: Radiofrequency ablation of AF, guided by optimal AI combined with impedance, can minimize atrial injury, prevent atrial failure, promote the recovery of atrial function, reduces intraoperative cough, pain, and postoperative gastrointestinal discomfort and use of PPIs. doi: https://doi.org/10.12669/pjms.38.3.4971 How to cite this:Qin X, Jiang X, Yuan Q, Xu G, He X. Optimal ablation index parameters for radiofrequency ablation therapy of atrial fibrillation. Pak J Med Sci. 2022;38(3):---------. doi: https://doi.org/10.12669/pjms.38.3.4971 This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/3.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

Tumor-killing nanoreactors fueled by tumor debris can enhance radiofrequency ablation therapy and boost antitumor immune responses

Radiofrequency ablation (RFA) is clinically adopted to destruct solid tumors, but is often incapable of completely ablating large tumors and those with multiple metastatic sites. Here we develop a CaCO3-assisted double emulsion method to encapsulate lipoxidase and hemin with poly(lactic-co-glycolic acid) (PLGA) to enhance RFA. We show the HLCaP nanoreactors (NRs) with pH-dependent catalytic capacity can continuously produce cytotoxic lipid radicals via the lipid peroxidation chain reaction using cancer cell debris as the fuel. Upon being fixed inside the residual tumors post RFA, HLCaP NRs exhibit a suppression effect on residual tumors in mice and rabbits by triggering ferroptosis. Moreover, treatment with HLCaP NRs post RFA can prime antitumor immunity to effectively suppress the growth of both residual and metastatic tumors, also in combination with immune checkpoint blockade. This work highlights that tumor-debris-fueled nanoreactors can benefit RFA by inhibiting tumor recurrence and preventing tumor metastasis.

Hepatic Clostridium Perfringens Abscess Formation after Radiofrequency Ablation Therapy for Hepatocellular Carcinoma: Report of a Rare Case

Liver abscess formation is one of the major complications following radiofrequency ablation (RFA) in patients with hepatocellular carcinoma (HCC). <i>Clostridium perfringens</i> is a rare but fatal (mortality rate: 70–100%) organism that could lead to severe sepsis. We presented a case where a 63-year-old woman with diabetes mellitus, hypertension, chronic hepatitis B-related cirrhosis in Child-Pugh class A and HCC with initial TNM stage II who had undergone 2 sessions of transarterial chemoembolization. RFA was performed for 4 small HCC due to poor effect of previous transarterial chemoembolization. However, all 4 treated tumors developed liver abscesses presenting with septic shock within 1 day. Aspirated abscesses and blood culture both yielded <i>C. perfringens</i> infection. After intensive care, optimal intravenous antibiotic, and abscesses aspiration, the patient recovered successfully. All tumors achieved complete response during the follow-up period without local recurrence. The clinical presentations and risk factors of <i>C. perfringens</i>-related liver abscess after RFA will be discussed in this manuscript.

Comparison of data on locoregional radiofrequency ablation therapy and surgical resection of malignant liver tumors at Gomel regional clinical oncology center

Objective: to perform a comparative analysis of postoperative complications and hospital stay terms of in-patients with malignant liver tumors after atypical liver resection and locoregional radiofrequency ablation of liver metastases.Material and methods. We analyzed the data of 295 patients with malignant liver tumors who had undergone surgical resection or radiofrequency ablation of tumor nodes.Results. We have systemized the direct results of locoregional radiofrequency ablation under sonographic control and liver resection. 45 patients (17.8 %) after liver resection and 1 (2.3 %) patient after radiofrequency ablation developed grade III–IV complications according to the Clavien-Dindo classification. The frequency of complications is statistically significantly lower after radiofrequency ablation. The duration of hospital stay after radiofrequency ablation therapy was 4.5 ± 2.5 days. After surgical liver resection, patients stayed in hospital for 10.7 ± 2.3 days.Conclusion. Locoregional therapy provides a statistically significant reduction in the incidence of complications and reduces the duration of hospital stay compared to liver surgery.