Zhong, Qiaonan

Introduction: Ventricular arrhythmias, including ventricular tachycardia (VT) and ventricular fibrillation (VF), are associated with high mortality and morbidity. Sedation through agents like benzodiazepines, propofol, and opiates are mainstays of treatment but are limited by side effects. Dexmedetomidine is a α2-presynaptic receptor agonist with a safe and efficacious sedative profile. Furthermore, it has been recently proposed as a sedative agent in VT due its additional antiarrhythmic properties. Methods: A systemic literature review was conducted of MEDLINE, EMBASE, Cochrane, and Scopus. Randomized controlled trials comparing the incidence of ventricular arrhythmias of dexmedetomidine with placebo or an alternative sedative agent were included. Two researchers independently extracted the data and performed quality assessments. Results: We identified 6 studies that met the selection criteria. Our meta-analysis demonstrated significant reduction of the overall risk of ventricular arrhythmias in patients receiving dexmedetomidine (RR 0.35, 95% CI 0.16, 0.76). Furthermore, there was no significant difference in risk of mortality (RR 0.59 95% CI 0.12, 3.02). Dexmedetomidine also significantly increased the risk of bradycardia (RR 2.78 95% CI 2.00, 3.87). There was no significant difference in risk of tachycardia (RR 0.59 95% CI 0.12, 3.02) or hypotension (RR 1.07 95% CI 0.64, 1.81). Conclusions: Our study demonstrates that the dexmedetomidine reduces the risk of VA by 65% compared to control. Further prospective research is necessary to clarify the antiarrhythmic and sedative properties of dexmedetomidine and its potential effect on patient outcomes.

Introduction: Ventricular storms are managed with a combination of antiarrhythmic drugs (AAD) and ablation therapy. This study examines outcomes in patients who required cardiac intensive care unit (CICU) admission for ventricular storms. Methods: A retrospective cohort study was conducted of 200 random adult patients who admitted to the CICU at Mayo Clinic Rochester in 2016-2017 for ventricular storm. Continuous variables were analyzed with the Mann-Whitney U test. Categorical variables were analyzed with Fisher's exact test. Results: Of the 200 patients, 33 (16.5%) patients underwent ablation and AAD therapy for ventricular arrhythmias; 167 underwent AAD therapy alone. The patients in the ablation group were significantly younger (median of 60.3 vs. 72.7, U=1570, p<.001), had a lower Charlson Comorbidity Index (3.56 vs. 5.21, U=1916, p=.005), and a higher BMI (31.6 vs. 28.2, U=2028, p=.032). There was no difference in sex and race (white vs. non-white) between the two groups. The patients in the ablation groups had a significantly lower in-hospital mortality (0% vs. 20%, p=.001) and higher 1-year survival (91% vs. 63%, p=.001). There was no difference in length of stay in the CICU, length of stay in the hospital, or rate of hospital readmission within one year of discharge. Conclusions: Our study indicates that critically ill patients who undergo ablation and AAD for ventricular arrhythmias have decreased mortality compared to patients who underwent AAD therapy alone. More research is needed to elucidate whether this survival benefit is secondary to differences in treatment or baseline comorbidities in the two groups. Table 1: Characteristics and outcomes of patients undergoing ventricular storm treatment. Data is reported either as median or number of occurrences (%). Antiarrhythmic drug (AAD), Charlson Comorbidity Index (CCI), Body Mass Index (BMI), Cardiac Intensive Care Unit (CICU), Length of Stay in days (LOS). * Significance with p values < .05

Purpose. To assess the antiarrhythmic properties of dexmedetomidine in patients in the intensive care unit. Methods. A literature review was conducted with Ovid MEDLINE (R), Cochrane Central Register of Controlled Trials, Cochrane Database of Systematic Reviews, Embase, and Scopus. Study Selection. Randomized controlled trials were included, examining the incidence of ventricular arrhythmias, ventricular tachycardia, or ventricular fibrillation with dexmedetomidine compared to placebo or an alternative sedative agent. For each publication that met the selection criteria, the patient demographics, incidence of arrhythmias, mortality, and adverse events were collected. Data extraction was carried out by two authors independently. Results. We identified 6 out of 126 studies that met the selection criteria for our meta-analysis, all of which focused on the perioperative cardiac surgery period. Patients receiving dexmedetomidine demonstrated a significant reduction of the overall incidence of ventricular arrhythmias (RR 0.35, 95% CI 0.16, 0.76). In particular, dexmedetomidine significantly decreased the risk of ventricular tachycardia compared with control (RR 0.25, 95% CI 0.08, 0.80, I2 0%). Regarding adverse events, dexmedetomidine significantly increased the frequency of bradycardia (RR 2.78 95% CI 2.00, 3.87). However, there was no significant difference in mortality (RR 0.59 95% CI 0.12, 3.02). Conclusion. From this meta-analysis, we report a decreased incidence of ventricular tachycardia with dexmedetomidine in critically ill patients. This result favors the use of dexmedetomidine for its antiarrhythmic properties.

Abstract Background The clinical diagnosis of Parkinson's disease (PD) requires the presence of parkinsonism and supportive criteria that include a clear and dramatic beneficial response to dopaminergic therapy. Our aim was to test the diagnostic criterion of dopaminergic response by evaluating its association with pathologically confirmed diagnoses in a large population of parkinsonian patients. Methods We reviewed clinical data maintained in an electronic medical record from all patients with autopsy data who had been seen in the Movement Disorders Center at Washington University, St. Louis, between 1996 and 2018. All patients with parkinsonism who underwent postmortem neuropathologic examination were included in this analysis. Results There were 257 unique parkinsonian patients with autopsy‐based diagnoses who had received dopaminergic therapy. Marked or moderate response to dopaminergic therapy occurred in 91.2% (166/182) of those with autopsy‐confirmed PD, 52.0% (13/25) of those with autopsy‐confirmed multiple systems atrophy, 44.4% (8/18) of those with autopsy‐confirmed progressive supranuclear palsy, and 1 (1/8) with autopsy‐confirmed corticobasal degeneration. Other diagnoses were responsible for the remaining 24 individuals, 9 of whom had a moderate response to dopaminergic therapy. Conclusion A substantial response to dopaminergic therapy is frequent but not universal in PD. An absent response does not exclude PD. In other neurodegenerative disorders associated with parkinsonism, a prominent response may also be evident, but this occurs less frequently than in PD. © 2020 International Parkinson and Movement Disorder Society