Lidocaine for prevention of reperfusion ventricular fibrillation after release of aortic cross-clamping

Early Graft Reperfusion and Arrhythmias After Coronary Artery Bypass Grafting

Background Arrhythmia after coronary artery bypass grafting (CABG) may occur immediately after the abrupt onset of reperfusion via all coronary bypass grafts simultaneously. We investigated whether early reperfusion of the left anterior descending coronary artery before weaning from cardiopulmonary bypass would decrease the frequency of early arrhythmias after CABG. We compared patients undergoing release of the left internal thoracic artery (LITA) graft flow before versus after aortic declamping during CABG. Methodology In total, 109 consecutive patients undergoing CABG were retrospectively analyzed. The heart rhythms after CABG of 46 patients with flow release from LITA before aortic declamping (study group) were compared with 63 patients with complete onset of reperfusion of all coronary bypass grafts simultaneously after aortic declamping (controls). Early arrhythmias were recorded and included atrial fibrillation, ventricular tachycardia, ventricular fibrillation, and arrhythmias necessitating temporary pacemaker support. Results Early arrhythmias occurred in seven out of 46 study group patients with the early release of LITA graft flow compared with 21 out of 63 controls (15.2% vs. 33.3%, p = 0.033). Creatine kinase-myocardial band levels were lower in the study group than in the controls (27.5 ± 58.4 vs. 33.0 ± 48.0, p = 0.004, respectively). Sinus rhythm was achieved in all but three patients before extubation including two in the study group and one in the controls. Conclusions The simple maneuver of releasing LITA graft flow before aortic declamping during CABG allows gradual reperfusion of the myocardium and may ensure early rhythm control.

The efficacy and safety of intraoperative intravenous amiodarone in patients undergoing on-pump coronary artery bypass grafting surgery: a systemic review and PRISMA-compliant meta-analysis

BACKGROUND

To evaluate the clinical efficacy and safety of intraoperative intravenous amiodarone for arrhythmia prevention in on-pump coronary artery bypass grafting (CABG) patients.

METHODS

A meta-analysis of randomized controlled trials was conducted. Pubmed, Embase, Cochrane Library, Ovid, China National Knowledge Infrastructure, and the Wan Fang database until July 1th, 2023. The primary outcomes of interest included the incidences of intra- and post-operative atrial fibrillation (POAF), ventricular fibrillation, or any arrhythmia, including atrial fibrillation, ventricular fibrillation, ventricular tachycardia, premature ventricular contraction, and sinus bradycardia. For continuous and dichotomous variables, treatment effects were calculated as the weighted mean difference (WMD)/risk ratio (RR) and 95% confidence interval (CI).

RESULTS

A database search yielded 7 randomized controlled trials including 608 patients, where three studies, including three treatments (amiodarone, lidocaine, and saline), contributed to the clinical outcome of atrial fibrillation, ventricular fibrillation, or any arrhythmia. Meta-analysis demonstrated that amiodarone can significantly reduce the incidence of POAF (RR, 0.39; 95%CI: 0.20, 0.77; P = 0.007, I2 = 0%) in patients undergoing on-pump CABG; there was no statistically significant influence on intra-operative atrial fibrillation, intra- and post-operative ventricular fibrillation, or any arrhythmia.

CONCLUSIONS

The current study suggests that intraoperative administration of intravenous amiodarone may be safe and effective in preventing POAF in patients undergoing on-pump CABG. More well-designed clinical trials are needed to validate this result.

Comparison of amiodarone and esmolol for prevention of reperfusion ventricular fibrillation in individuals undergoing heart valve or aortic surgery: a study protocol for a randomized controlled clinical trial

BACKGROUND

Amiodarone and esmolol can help to prevent and treat post-cardiac surgery reperfusion ventricular fibrillation. However, the relative efficacies of these two drugs remain unknown. The aim of the current trial is to compare the performances of amiodarone and esmolol for preventing reperfusion ventricular fibrillation following open heart surgery.

METHODS/DESIGN

This is a single-center, prospective, double-blind, controlled clinical trial. A total of 260 patients undergoing heart valve or aortic surgery will be assigned randomly to treatment with prophylactic esmolol (intervention group) or amiodarone (control group). The main outcome is the incidence of reperfusion ventricular fibrillation following aortic opening during extracorporeal circulation. The secondary outcomes are the rate of automatic cardiac resuscitation, energy and frequency of electrical defibrillation, number of electrical defibrillations, and pacemaker use in the two groups of patients. Information on the patients' general condition and the durations of anesthesia, extracorporeal circulation, aortic occlusion, and operation time will be recorded. We will also compare the heart rate, mean arterial pressure, and central venous pressure between the two groups of patients at induction of anesthesia (T1), start of surgery (T2), start of extracorporeal circulation (T3), aortic block (T4), aortic opening (T5), after opening for 10 (T6), 20 (T7), and 30 min (T8), at cessation of extracorporeal circulation (T9), and at the end of surgery (T10) and compare blood gas analysis results at T1, T5, T9, and T10.

DISCUSSION

This study will determine if prophylactic esmolol is more effective than amiodarone for reducing the incidence of reperfusion ventricular fibrillation in patients undergoing heart valve or aortic surgery.

TRIAL REGISTRATION

China Clinical Trials Registry ChiCTR1900026429. Registered on 2019.10.9.

The Effect of Prophylactic Intravenous Amiodarone Administration on Reperfusion Ventricular Fibrillation in Patients With Left Ventricular Hypertrophy Undergoing Cardiopulmonary Bypass Surgery: Protocol for a Randomized Double-Blind Clinical Trial

BACKGROUND

Ventricular fibrillation (VF) is a common arrhythmia that occurs after the release of aortic cross-clamp (ACC) in patients undergoing cardiopulmonary bypass (CPB) surgery. Repeated defibrillation and long duration of VF could increase myocardial injuries. In patients with left ventricular hypertrophy (LVH), VF is easier to occur and more difficult to be terminated. Amiodarone, known as class III antiarrhythmic agent, has the prominent properties of converting VF and restoring the sinus rhythm. Before ACC release, administration of amiodarone has been confirmed useful to reduce occurrence of VF. However, few studies are focused on the effect of amiodarone before ACC release on reducing VF in patients with LVH.

OBJECTIVE

This study aimed at determining the efficacy of prophylactic intravenous amiodarone administration on reperfusion VF after release of ACC in patients with LVH undergoing CPB surgery.

METHODS

This will be a prospective, randomized, double-blind, placebo-controlled trial. The trial will enroll 54 patients with LVH aged 18-75 years who will undergo CPB surgery. All eligible participants will be randomly allocated to either the amiodarone or placebo group by using the block randomization in a 1:1 ratio. The primary end point will be the incidence rate of VF 30 minutes after ACC release and be assessed using the Fisher exact test. All data will be analyzed in accordance with the intention-to-treat principle.

RESULTS

The study began in August 2022, and the data collection will take place for the next 2 academic years. As of this writing, 21 participants have already been recruited for the study.

CONCLUSIONS

With this trial, we are hoping to demonstrate that prophylactic infusion of amiodarone before ACC release could reduce the occurrence of reperfusion VF in patients with LVH.

TRIAL REGISTRATION

ClinicalTrials.gov ChiCTR2000035057; https://www.chictr.org.cn/showprojen.aspx?proj=57145.

INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID)

DERR1-10.2196/40115.

Single- versus multidose cardioplegia in adult cardiac surgery patients: A meta-analysis

OBJECTIVE

To compare outcomes of single (intervention group: del Nido [DN], and histamine-tryptophan-ketoglutarate) versus multidose (control group) cardioplegia in the adult cardiac surgery patients.

METHODS

Medical search engines were interrogated to identify relevant randomized controlled trials and propensity-score matched cohorts. Meta-analysis was conducted for primary (in-hospital/30-day mortality) and secondary (ischemic and cardiopulmonary bypass [CPB] times, reperfusion fibrillation, peak of cardiac enzymes, myocardial infarction) endpoints. Subgroup analyses were conducted for study design and type of intervention, and meta-regression for primary outcome included type of surgery and left ventricular ejection fraction as moderators.

RESULTS

Ten randomized controlled trials and 13 propensity-score matched cohorts were included, reporting on 5516 patients. Estimates are expressed as (parameter value [OR, odds ratio; MD, mean difference; SMD, standardized mean difference]/unit of measure [95% confidence interval], P value). DN reduced ischemic time (MD, -7.18 minutes [-12.52 to -1.84], P < .01), CPB time (MD, -10.44 minutes [-18.99 to -1.88], P .01), reperfusion fibrillation (OR, 0.16 [0.05-0.54], P < .01), and cardiac enzymes (SMD -0.17 [-0.29, 0.05], P < .01) compared with multidose cardioplegia. None of these beneficial effects were reproduced by histamine-tryptophan-ketoglutarate, which instead increased CPB time (MD, 2.04 minutes [0.73-3.37], P < .01) and reperfusion fibrillation (OR, 1.80 [1.20-2.70], P < .01). There was no difference in mortality and myocardial infarction between single and multidose, independently of type of surgery or left ventricular ejection fraction.

CONCLUSIONS

DN decreases operative times, reperfusion fibrillation, and surge of cardiac enzymes compared with multidose cardioplegia.

Effect of opioid-free anaesthesia on post-operative period in cardiac surgery: a retrospective matched case-control study

BACKGROUND

No study has been conducted to demonstrate the feasibility of an opioid-free anesthesia (OFA) protocol in cardiac surgery to improve patient care. The aim of the present study was to evaluate the effect of OFA on post-operative morphine consumption and the post-operative course.

METHODS

After retrospectively registering to clinicaltrial.gov (NCT03816592), we performed a retrospective matched cohort study (1:1) on cardiac surgery patients with cardiopulmonary bypass between 2018 and 2019. Patients were divided into two groups: OFA (lidocaine, dexamethasone and ketamine) or opioid anaesthesia (OA) (sufentanil). The main outcome was the total postoperative morphine consumption in the 48 h after surgery. Secondary outcomes were rescue analgesic use, a major adverse event composite endpoint, and ICU and hospital length of stay (LOS).

RESULTS

One hundred ten patients were matched (OFA: n = 55; OA: n = 55). On inclusion, demographic and surgical data for the OFA and OA groups were comparable. The total morphine consumption was higher in the OA group than in the OFA group (15 (6-34) vs 5 mg (2-18), p = 0.001). The pain score during the first 48 post-operative hours did not differ between the two groups. Creatinine values did not differ on the first post-operative day (80 (IQR: 66-115) vs 77 mmol/l (IQR: 69-95), p = 0.284). Incidence of the composite endpoint was lower in the OFA group (25 patients (43%) vs 38 patients (68%), p = 0.021). The time to extubation and the ICU stays were shorter in the OFA group (3 (1-5) vs 5 (3-6) hours, p = 0.001 and 2 (1-3) vs 3 (2-5) days, p = 0.037).

CONCLUSION

The use of OFA was associated with lower morphine consumption. OFA might be associated with shorter intubation time and ICU stays. Further randomized studies are needed to confirm these results.

TRIAL REGISTRATION

This study was retrospectively registered to ct2 (identifier: NCT03816592 ) on January 25, 2019.

Efficacy of amiodarone and lidocaine for preventing ventricular fibrillation after aortic cross-clamp release in open heart surgery: a meta-analysis of randomized controlled trials

OBJECTIVE

The relative preventative efficacy of amiodarone and lidocaine for ventricular fibrillation (VF) after release of an aortic cross-clamp (ACC) during open heart surgery has not been determined. This meta-analysis was designed to systematically evaluate the influence of amiodarone, lidocaine, or placebo on the incidence of VF after ACC.

METHODS

Prospective randomized controlled trials (RCTs) that compared the VF-preventative effects of amiodarone with lidocaine, or amiodarone or lidocaine with placebo were included. PubMed, EMBASE, and the Cochrane Library were searched for relevant RCTs. Fixed or randomized effect models were applied according to the heterogeneity of the data from the selected studies.

RESULTS

We included eight RCTs in the analysis. Pooled results suggested that the preventative effects of amiodarone and lidocaine were comparable (relative risk (RR)=1.12, 95% confidence interval (CI): 0.70 to 1.80, P=0.63), but both were superior to the placebo (amiodarone, RR=0.71, 95% CI: 0.51 to 1.00, P=0.05; lidocaine, RR=0.63, 95% CI: 0.46 to 0.88, P=0.006). The percentage of patients requiring electric defibrillation counter shocks (DCSs) did not differ significantly among patients administered amiodarone (RR=0.21, 95% CI: 0.04 to 1.19, P=0.08), lidocaine (RR=2.44, 95% CI: 0.13 to 44.02, P=0.55), or the placebo (RR=0.56, 95% CI: 0.25 to 1.25, P=0.16).

CONCLUSIONS

Amiodarone and lidocaine are comparably effective in preventing VF after ACC, but the percentage of patients who subsequently require DCSs does not differ among those administered amiodarone, lidocaine, or placebo.

The effect of lidocaine and amiodarone on prevention of ventricular fibrillation in patients undergoing coronary artery bypass grafting

OBJECTIVE

Ventricular fibrillation is common after aortic declamping in patients undergoing open heart surgery. This situation has a negative impact on morbidity and mortality. The aim of this prospective study was to compare the effect of administering lidocaine versus amiodarone before aortic declamping during elective coronary bypass grafting, paying close attention to when the initial effect of amiodarone sets in.

METHODS

In this double blind, prospective, randomized, controlled study, 86 patients who were candidates for elective coronary artery bypass grafting were recruited into three groups: group lidocaine (group L, n=29); group amiodarone (group A, n=27); and group placebo (group P, n=30). Group L patients received 1.5 mg/kg of lidocaine 2 minutes before aortic declamping and group A patients received 300 mg of amiodarone intravenously 15 minutes before release of the aortic cross clamp. The primary endpoints were the incidence of ventricular fibrillation and the number of shocks required to terminate ventricular fibrillation.

RESULTS

The frequency of ventricular fibrillation occurrence was significantly higher in group P (70%) when compared with group A (37%) and group L (38%) (P=.017). There was no statistically significant difference between the amiodarone and the lidocaine groups regarding ventricular fibrillation. However, when ventricular fibrillation occurred, the percentage of patients requiring electrical defibrillation was significantly higher in both group L and group P when compared with group A (P=.023).

CONCLUSION

We suggest that during coronary arterial bypass surgery, administration of an amiodarone regime before release of the aortic cross clamp, paying particular attention to the start of the initial effect of amiodarone, is no more effective than lidocaine for prevention from arrhythmia; however, amiodarone reduces the need for electrical defibrillation.

Sheep (Ovis aries) as a model for cardiovascular surgery and management before, during, and after cardiopulmonary bypass

Because of its similarity to humans in important respects, sheep (Ovis aries) are a common animal model for translational research in cardiovascular surgery. However, some unique aspects of sheep anatomy and physiology present challenges to its use in these complicated experiments. In this review, we discuss relevant anatomy and physiology of sheep and discuss management before, during, and after procedures requiring cardiopulmonary bypass to provide a concise source of information for veterinarians, technicians, and researchers developing and implementing protocols with this model.

Effects of a Novel Cyclohexane Dicarboximide Derivative, ST-6, on Reperfusion-Induced Arrhythmia in Rats

The present study was designed to determine whether a novel cyclohexane dicarboximide derivative, ST-6, 2-[4-[4-(chlorophenyl)-4-hydroxy-1-piperidinyl]butyl]hexahydro-1H-isoindol-1,3(2H)-dione, prevents reperfusion-induced ventricular arrhythmias. Pentobarbital-anesthetized rats were subjected to left coronary artery occlusion for 4 min followed by 4-min reperfusion, and the incidence of their ventricular arrhythmias was examined. The coronary occlusion of control rats induced ventricular tachycardia and fibrillation, eventually leading to sudden death. The intravenous injection of 0.1 to 2 mg/kg ST-6 prior to the occlusion resulted in a dose-dependent suppression of the ventricular arrhythmias. The suppression of ventricular fibrillation was also observed on the intraperitoneal and intradoudenal administration of 2 to 10 mg/kg ST-6 15 min prior to coronary occlusion. Antiarrhythmic effects of this agent (0.5 mg/kg per min) were compared with those of other antiarrhythmic agents including lidocaine (0.1 mg/kg per min), sematilide (0.3 mg/kg per min), and diltiazem (0.5 mg/kg per min) by administrating the agents from 1 min after the coronary occlusion to the end of 4-min reperfusion. Antiarrhythmic effects of ST-6 were similar in degree to those of lidocaine and diltiazem, whereas no significant prevention by sematilide was seen. The results suggest that ST-6 may be capable of suppressing reperfusion-induced arrhythmias following oral or intravenous administration.