[Repeated stellate ganglion blockade for the treatment of ventricular tachycardia storm in patients with nonischemic cardiomyopathy: a new therapeutic option for patients with malignant arrhythmias].

Objectives: This study sought to describe our institutional experience of repeated percutaneous stellate ganglion blockade (R-SGB) as a treatment option for drug-refractory electrical storm in patients with nonischemic cardiomyopathy (NICM). Methods: This prospective observational study included 8 consecutive NICM patients who had drug-refractory electrical storm and underwent R-SGB between June 1, 2021 and January 31, 2022. Lidocaine (5 ml, 1%) was injected in the vicinity of the left stellate ganglion under the guidance of ultrasound, once per day for 7 days. Data including clinical characteristics, immediate and long-term outcomes, and procedure related complications were collected. Results: The mean age was (51.5±13.6) years. All patients were male. 5 patients were diagnosed as dilated cardiomyopathy, 2 patients as arrhythmogenic right ventricular cardiomyopathy and 1 patient as hypertrophic cardiomyopathy. The left ventricular ejection fraction was 37.8%±6.6%. After the treatment of R-SGB, 6 (75%) patients were free of electrical storm. 24 hours Holter monitoring showed significant reduction in ventricular tachycardia (VT) episodes from 43.0 (13.3, 276.3) to 1.0 (0.3, 34.0) on the first day following R-SGB (P<0.05) and 0.5 (0.0, 19.3) after whole R-SGB process (P<0.05). There were no procedure-related major complications. The mean follow-up was (4.8±1.1) months, and the median time of recurrent VT was 2 months. Conclusion: Minimally invasive R-SGB is a safe and effective method to treat electrical storm in patients with NICM.

[Clinical characteristics and long-term follow-up results of radiofrequency ablation for the treatment of ventricular tachycardia in patients with arrhythmogenic left ventricular cardiomyopathy].

Objective: To investigate the acute and long-term outcome of catheter ablation for the treatment of ventricular tachycardia (VT) in patients with arrhythmogenic left ventricular cardiomyopathy (ALVC). Methods: This retrospective, cross-sectional study enrolled ALVC patients undergoing radiofrequency ablation for the treatment of VT at the First Affiliated Hospital of Nanjing Medical University from January 2011 to December 2018 and collected their clinical characteristics and intraoperative electrophysiological examination. Patients were followed up every 6 months after radiofrequency ablation until August 2021. Echocardiographic results and VT recurrence post radiofrequency ablation were analysed. Results: Totally 12 patients were enrolled (mean age: (42±15) years, 11 males(11/12)). The mean of left ventricular end diastolic diameter (LVDd) and left ventricular ejection fraction (LVEF) were (51±5)mm and (65±5)%, respectively. Twelve VTs were induced in 10 patients during the electrophysiological study, and the mean tachycardia cycle length was (293±65) ms. Three-dimensional substrate mapping revealed the diseased area at endocardial site in one patient, at epicardial sites in the other 11 patients (involved endocardial sites in 2 cases) with the basal part near the mitral annulus being the predilection for the substrate (10/11). After the catheter ablation at the endocardial and epicardial sites respectively, the complete procedure endpoint was achieved in all patients (VT cannot be induced post ablation). The median follow-up time was 65 (25, 123) months. One patient was lost to follow-up, and the other 11 patients survived without VT. No significant cardiac function deterioration was detected by the echocardiographic examination ((51±5)mm vs. (52±5)mm, P>0.05 for LVDd, (65±5)% vs. (60±6)%, P>0.05 for LVEF) at the end of follow-up. Conclusion: After radiofrequency ablation, the complete procedure endpoint is achieved in ALVC patients, and the catheter ablation provides long-term ventricular tachycardia control during the long-term follow-up.

Sensitive and selective LC-MS/MS assay for quantitation of flutrimazole in human plasma.

OBJECTIVE: A highly sensitive liquid chromatography-tandem mass spectrometry method was developed and validated for the determination of flutrimazole in human plasma. This study was to investigate the application of sensitive and selective LC-MS/MS method for quantitation of flutrimazole in human plasma. MATERIALS AND METHODS: The analysis and internal standard were extracted with ether and hexane (v:v, 1:1) followed by a rapid isocratic elution with a 0.1% formic acid/methanol (v:v, 20:80) on a C18 column (50 mm × 2.1 mm I.D.) and subsequent analysis by mass spectrometry in the multi-reaction-monitoring mode. The precursor to production transitions of m/z 279.0 → 183.1 and m/z 441.0 → 295.1 were used to measure the analyte and the internal standard. RESULTS: The assay was linear over the concentration range of 0.996-99.6 ng•mL-1 for flutrimazole in human plasma. The lower limit of quantification was 0.996 ng•mL-1 and the extraction recovery was larger than 78.83% for flutrimazole. The inter- and intra-day precision of the method at three concentrations was less than 9.26%. CONCLUSIONS: The LC-MS/MS method was firstly applied to quantitation of flutrimazole in human plasma.

Pharmacokinetics and bioequivalence of single dose and multiple doses of immediate- and extended-release formulations of dexibuprofen in healthy Chinese subjects.

OBJECTIVE: To compare the pharmacokinetic (PK) profiles and bioequivalence of the extended-release (ER) and immediate-release (IR) formulations of dexibuprofen (DI) in healthy Chinese volunteers after single dose and multiple doses. MATERIALS: Zefen® (IR capsule, containing 150 mg DI, Suzhou No.4 Pharmaceutical Factory, Jiangsu, China) and ER capsule (containing 225 mg DI, Tianjin Zhongtian Pharmaceutical Co. Ltd., Tianjin, China). METHODS: This was an open, randomized, two-period crossover study. Eligible subjects were healthy male Chinese volunteers. 22 subjects were randomly assigned to receive a single 450 mg dose of the test or reference formulation on the first day. During the next 6 days, the test group received a multiple-dose of ER DI capsule (450 mg, b.i.d.) and the reference group took a multiple-dose of IR DI capsule (300 mg, t.i.d.), respectively. Multiple blood samples were collected, and plasma concentrations of DI were analyzed using high performance liquid chromatography (HPLC) system. After a 9-day washout period, the subjects were administered the alternate formulation. Bioequivalence was concluded if the 90% confidence interval (CI) for the ratio between test and reference was within accepted limits. Adverse events (AEs) were monitored and documented throughout the confinement in the clinic and washout phases of each study period. RESULTS: 21 subjects completed the single dose administration and 20 subjects were evaluable for the multiple doses PK parameters. Single-dose Mean AUC0-t and AUC0-inf for ER formulation were 116.14 ± 21.54 mg·h/l and 117.60 ± 22.27 mg·h/l, and for IR formulation, were 107.25 ± 23.48 mg·h/l and 108.18 ± 23.93 mg·h/l, with the 90% CI within the limits accepted for bioequivalence. Mean Cmax for ER and IR formulations were 22.30 ± 5.17 mg/l and 30.26 ± 13.54 mg/l, respectively. And median tmax for ER and IR formulations were 4.5 h and 2.0 h. The retard quotient (delta R) for ER product was 1.9 ± 0.93, which indicated an intermediate extended release effect. Multiple-dose Mean AUC0-24 for ER formulation was 217.93 ± 41.07 mg·h/l and for IR formulation was 199.33 ± 37.32 mg·h/l. Other PK parameters of ER and IR formulations were as follows: median tmax were 4.8 h and 2.0 h, Css-max were 20.21 ± 2.69 mg/l and 19.71 ± 3.46 mg/l, Css-min were 2.47 ± 0.99 mg/l and 2.48 ± 0.99 mg/l, Cav were 9.08 ± 1.71 mg/l and 8.31 ± 1.56 mg/l, respectively. CONCLUSIONS: This study found that in these subjects, the absorption rates of the two DI formulations were not bioequivalent, but at steady state, the daily exposure provided by less frequent DI ER dosing was not significantly different from the same daily dose with DI IR capsules, administered more frequently.