Concomitant use of beta-1 adrenoreceptor blocker and norepinephrine in patients with septic shock. Reply to a letter to the authors

Efficacy and safety of 1C class antiarrhythmic agent (propafenone) for supraventricular arrhythmias in septic shock compared to amiodarone: protocol of a prospective randomised double-blind study

INTRODUCTION

Supraventricular arrhythmias contribute to haemodynamic compromise in septic shock. A retrospective study generated the hypothesis that propafenone could be more effective than amiodarone in achieving and maintaining sinus rhythm (SR). Certain echocardiographic parameters may predict a successful cardioversion and help in the decision on rhythm or rate control strategy.

METHODS AND ANALYSIS

The trial includes septic shock patients with new-onset arrhythmia, but without severe impairment of the left ventricular ejection fraction. After baseline echocardiography, the patient is randomised to receive a bolus and maintenance dose of either amiodarone or propafenone. The primary outcome is the proportion of patients that have achieved rhythm control at 24 hours after the start of the infusion. The secondary outcomes are the percentages of patients that needed rescue treatments (DC cardioversion or unblinding and crossover of the antiarrhythmics), the recurrence of arrhythmias, intensive care unit mortality, 28-day and 1-year mortality. In the posthoc analysis, we separately assess subgroups of patients with pulmonary hypertension and right ventricular dysfunction. In the exploratory part of the study, we assess whether the presence of a transmitral diastolic A wave and its higher velocity-time integral is predictive for the sustainability of mechanical SR and whether the indexed left atrial endsystolic volume is predictive of recurrent arrhythmia. Considering that the restoration of SR within 24 hours occurred in 74% of the amiodarone-treated patients and in 89% of the patients treated with propafenone, we plan to include 200 patients to have an 80% chance to demonstrate the superiority of propafenone at p=0.05.

ETHICS AND DISSEMINATION

The trial is recruiting patients according to its second protocol version approved by the University Hospital Ethical Board on the 6 October 2017 (No. 1691/16S-IV). The results will be disseminated through peer reviewed publications and conference presentations.

TRIAL REGISTRATION NUMBER

NCT03029169.

Propafenone for supraventricular arrhythmias in septic shock-Comparison to amiodarone and metoprolol

PURPOSE

The occurence of supraventricular arrhythmias associate with an unfavourable prognosis in septic shock. Propafenone could be a feasible antiarrhythmic.

MATERIALS AND METHODS

Patients collected over a period of 24months were divided into the three groups based on antiarrhythmic: Group1(amiodarone), Group2(propafenone), Group3(metoprolol). Type of arrhythmia, cardioversion rates, demographic, haemodynamic, laboratory parameters were recorded in the first 24h. The outcome data were compared between the groups.

RESULTS

234 patients (99.1% ventilated) were included, the prevailing arrhythmia was acute onset atrial fibrillation (AF,69.7%). Except for the dosage of noradrenaline (0.35(0.14-0.78) in Group1(n=142)vs 0.25(0.10-0.50),p<0.01 in Group2(n=78)vs 0.14(0.07-0.25)μg/kg·min,p<0.05 in Group3(n=14)) the ejection fraction of left ventricle, rates of renal replacement therapy, arterial lactate and procalcitonin levels were not different between the groups. The cardioversion rate in Group1(74%) was lower than in Group2(89%) and Group3(92%). ICU and 28-day mortalities of Group1 were not significantly higher than in Group2 and Group3. Multivariate analysis demonstrated higher 12-month mortality in Group1 than in Group2 (HR1.58(1.04;2.38),p=0.03).

CONCLUSIONS

Propafenone demonstrated a higher cardioversion rate than amiodarone with a similar impact on the outcome. Patients remaining in acute onset arrhythmia did not demonstrate significantly higher ICU, 28-day and 12-month mortalities compared to those successfully cardioverted or to those having chronic AF.