BACKGROUND

Postoperative atrial fibrillation (POAF) is the most common arrythmia to occur after cardiovascular surgery. Inflammation being pivotal in POAF perpetuation has been utilized as a therapeutic target. Owing to their anti-inflammatory and anti-oxidant effects, beta-blockers (BB) and N-acetylcysteine (NAC) became research interests in the pursuit for an effective POAF prevention strategy.

To determine the efficacy of NAC plus BB versus BB alone in preventing POAF in cardiac surgery patients.

A literature search using the following search engines: PubMed/Medline, Cochrane Review Central, Clinical Trials Registry, ResearchGate, Mendeley and Google Scholar for relevant randomized trials were conducted. Published and unpublished studies indexed from inception until 2023 were included. Three independent reviewers evaluated the randomized clinical trials (RCTs) for eligibility. The pooled estimates for POAF prevention as primary outcome and MACE, mortality, myocardial infarction, stroke, ICU LOS and hospital LOS as secondary outcomes were measured using the RStudio statistical software.

Seven eligible RCTs allocated 1069 cardiac surgery patients to NAC + BB (n=539) and BB alone (N = 530) treatment arms. The effect estimate using random effect model disclosed significantly reduced POAF events (RR 0.62, 95% CI [0.44, 0.86], p = 0.005) in those on NAC + BB. While no statistical difference between the study arms were demonstrated in reducing mortality (RR 0.63, 95% CI [0.23, 1.73], p = 0.37); myocardial infarction (RR 1.02, 95% CI [0.49, 2.13], p = 0.96); stroke (RR 0.95, 95% CI [0.24, 3.68], p = 0.94); ICU LOS (std. mean difference 0.14, 95% CI [-0.43, 0.70], p = 0.41), and hospital LOS (std. mean difference 0.08, 95% CI [-0.06, 0.21], p = 0.19).

Among cardiac surgery patients, the use of NAC in combination with BB compared with BB alone significantly reduced POAF.

Background and Objective: Premature ventricular complex (PVC) burden exhibits one of three circadian types, classified as fast-type, slow-type, and independent-type PVC. It is unknown whether PVC circadian types have different heart rate variability (HRV) parameter values. Therefore, this study aimed to evaluate differences in HRV circadian rhythm among fast-, slow-, and independent-type PVC. Methods: This cross-sectional observational study consecutively recruited 65 idiopathic PVC subjects (23 fast-, 20 slow-, and 22 independent-type) as well as five control subjects. Each subject underwent a 24-hour Holter to examine PVC burden and HRV. HRV analysis included components that primarily reflect global, parasympathetic, and sympathetic activities. Repeated measures analysis of variance was used to compare differences in HRV circadian rhythm by PVC type. Results. The average PVC burden was 15.7%, 8.4%, and 13.6% in fast-, slow-, and independent-type idiopathic PVC subjects, respectively. Global, parasympathetic nervous system, and sympathetic nervous system HRV parameters were significantly lower in independenttype PVC versus fast- and slow-type PVC throughout the day and night. Furthermore, we unexpectedly found that tendency towards sympathetic activity dominance during nighttime was only in independent-type PVC. Conclusion The HRV parameters are reduced in patients with independent-type PVC compared to fast- and slowtype PVC. Future research is warranted to determine possible differences in the prognosis between the three PVC types.
Ventricular Premature Complexes ; Circadian Rhythm ; Autonomic Nervous System

The electrocardiographic analysis of heart blocks provides great opportunities for the discussion of mechanisms of electrical cardiac conduction, serving as “teachable moments” in medicine. Recognition of heart blocks can sometimes be a challenge as they can present in many forms, different severities and levels of blocks that present as varied patterns on electrocardiographic tracing. The ultimate key to correct diagnosis rests on adequate understanding of normal electrophysiology of the electrical system of the heart. While it is vital to recognize the pattern, we should always know and understand the physiology behind the pattern. This article presents a detailed analysis of a case of heart block which can easily be misinterpreted on first look. The case is featured not for its rarity but for the interesting concepts in cardiac electrophysiology that are highlighted. Navigation of the different elements of tracing can be an adventure and a great learning experience enjoyed by both students and experts.
Heart Block ; Electrocardiography

BACKGROUND: Dysfunction of the gap junction channel protein connexin 43 (Cx43) contributes to myocardial ischemia/reperfusion (I/R)-induced ventricular arrhythmias. Cx43 can be regulated by small ubiquitin-like modifier (SUMO) modification. Protein inhibitor of activated STAT Y (PIASy) is an E3 SUMO ligase for its target proteins. However, whether Cx43 is a target protein of PIASy and whether Cx43 SUMOylation plays a role in I/R-induced arrhythmias are largely unknown. METHODS: Male Sprague-Dawley rats were infected with PIASy short hairpin ribonucleic acid (shRNA) using recombinant adeno-associated virus subtype 9 (rAAV9). Two weeks later, the rats were subjected to 45 min of left coronary artery occlusion followed by 2 h reperfusion. Electrocardiogram was recorded to assess arrhythmias. Rat ventricular tissues were collected for molecular biological measurements. RESULTS: Following 45 min of ischemia, QRS duration and QTc intervals statistically significantly increased, but these values decreased after transfecting PIASy shRNA. PIASy downregulation ameliorated ventricular arrhythmias induced by myocardial I/R, as evidenced by the decreased incidence of ventricular tachycardia and ventricular fibrillation, and reduced arrythmia score. In addition, myocardial I/R statistically significantly induced PIASy expression and Cx43 SUMOylation, accompanied by reduced Cx43 phosphorylation and plakophilin 2 (PKP2) expression. Moreover, PIASy downregulation remarkably reduced Cx43 SUMOylation, accompanied by increased Cx43 phosphorylation and PKP2 expression after I/R. CONCLUSION PIASy downregulation inhibited Cx43 SUMOylation and increased PKP2 expression, thereby improving ventricular arrhythmias in ischemic/reperfused rats heart.
Rats ; Male ; Animals ; Myocardial Reperfusion Injury/metabolism* ; Connexin 43/genetics* ; Sumoylation ; Down-Regulation ; Rats, Sprague-Dawley ; Arrhythmias, Cardiac/drug therapy* ; Myocardial Ischemia/metabolism* ; RNA, Small Interfering/metabolism*

OBJECTIVE: To retrieve the evidence for threshold setting of multi-parameter electrocardiograph (ECG) monitors in intensive care unit (ICU), and summarize the best evidence. METHODS: After literature retrieval, clinical guidelines, expert consensus, evidence summary and systematic review that met the requirements were screened. Guidelines were evaluated by the appraisal of guidelines for research and evaluation II (AGREE II), expert consensus and systematic review were evaluated by the Australian JBI evidence-based health care center authenticity evaluation tool, and evidence summary was evaluated by the CASE checklist. High-quality literature was selected to extract evidence related to the use and setup of multi-parameter ECG monitors in the ICU. RESULTS: A total of 19 literatures were included, including 7 guidelines, 2 expert consensus, 8 systematic reviews, 1 evidence summary, and 1 national industry standard. After evidence extraction, translation, proofreading and summary, a total of 32 pieces of evidence were integrated. The included evidence involved the environmental preparation for the application of the ECG monitor, the electrical requirements of the ECG monitor, ECG monitor use process, ECG monitor alarm setting principles, ECG monitor alarm heart rate or heart rhythm monitoring setting, ECG monitor alarm blood pressure monitoring setting, ECG monitor alarm respiratory and blood oxygen saturation threshold setting, alarm delay warning time setting, adjusting alarm setting method, evaluating alarm setting time, improving the comfort of monitoring patients, reducing nuisance alarm report the occurrence, alarm priority processing, alarm intelligent processing and so on. CONCLUSIONS This summary of evidence involves many aspects of the setting and application of ECG monitor. According to the latest guidelines and expert consensus, it is updated and revised to guide healthcare workers to monitor patients more scientifically and safely, and aims to ensure patient safety.
Humans ; Clinical Alarms ; Australia ; Intensive Care Units ; Arrhythmias, Cardiac ; Electrocardiography ; Monitoring, Physiologic

Temporary cardiac pacing is an essential technique in the diagnosis and treatment of arrhythmias. Due to its urgency, complexity, and uncertainty, it is necessary to develop an evidence-based emergency operation norms. Currently, there is no specific consensus guidelines at home or abroad. The Emergency Branch of Chinese Medical Association organized relevant experts to draft the Chinese emergency expert consensus on bedside temporary cardiac pacing (2023) to guide the operation and application of bedside cardiac pacing. The formulation of the consensus adopts the consensus meeting method and the evidentiary basis and recommendation grading of the Oxford Center for Evidence-based Medicine in the United States. A total of 13 recommendations were extracted from the discussion on the methods of bedside temporary cardiac pacing, the puncture site of transvenous temporary cardiac pacing, the selection of leads, the placement and placement of leads, pacemaker parameter settings, indications, complications and postoperative management. The recommended consensus includes the choice between transcutaneous and transvenous pacing, preferred venous access for temporary transvenous pacing, the target and best guidance method for implantation of bedside pacing electrodes, recommended default pacemaker settings, recommended indications for sinoatrial node dysfunction, atrioventricular block, acute myocardial infarction, cardiac arrest, ventricular and supraventricular arrhythmias. They also recommended ultrasound guidance and a shortened temporary pacing support time to reduce complications of temporary transvenous cardiac pacing, recommended bedrest, and anticoagulation after temporary transvenous pacing. Bedside temporary cardiac pacing is generally safe and effective. Accurate assessment, correct selection of the pacing mode, and timely performance of bedside temporary cardiac pacing can further improve the survival rate and prognosis of related emergency patients.
Humans ; Cardiac Pacing, Artificial/methods* ; Pacemaker, Artificial ; Arrhythmias, Cardiac/therapy* ; Myocardial Infarction/therapy* ; Electrodes

OBJECTIVE: The transformations that occur in diterpenoid alkaloids during the process of sand frying for Chinese herbal medicine preparation have yet to be clarified. This study investigated the structural changes that take place in 3-acetylaconitine during a simulation of heat-processing and evaluated the toxicity and biological activity of the pyrolysis products. METHODS: The diterpenoid alkaloid 3-acetylaconitine was heated at 180 °C for 15 min to simulate the process of sand frying. The pyrolysis products were separated using column chromatography, and their structures were investigated using high-resolution electrospray ionization mass spectroscopy and nuclear magnetic resonance spectroscopy. Further, in vivo cardiotoxicity and acute toxicity of 3-acetylaconitine and its pyrolysis products were compared, and the aconitine-induced arrhythmia model was employed to evaluate the antiarrhythmic effect of the pyrolysis products. RESULTS: Two new diterpenoid alkaloids, pyroacetylaconitine and 16-epi-pyroacetylaconitine, a pair of epimers at C-16, were isolated. After comparing the structures of these compounds, possible transformation pathways were proposed. Compared with the prototype compound, 3-acetylaconitine, the cardiotoxicity and acute toxicity of the heat-transformed products were significantly decreased. In the biological activity assay, the two pyrolysis products exhibited an effective increase in ventricular premature beat latency, a reduction in the occurrence of ventricular tachycardia, as well as an increase in the rate of arrhythmia inhibition, implying strong antiarrhythmic activity. CONCLUSION Compared with 3-acetylaconitine, its pyrolysis products displayed lower toxicity and good antiarrhythmic effects; thus, they have potential for being developed into antiarrhythmic medicines. Please cite this article as: Wang YJ, Wang Y, Tao P. Structural characterization, in vivo toxicity and biological activity of two new pyro-type diterpenoid alkaloids derived from 3-acetylaconitine. J Integr Med. 2023; 21(3): 302-314.
Humans ; Aconitine/chemistry* ; Cardiotoxicity ; Sand ; Alkaloids/toxicity* ; Arrhythmias, Cardiac/drug therapy* ; Diterpenes/toxicity*

COVID-19 primarily presents as a pulmonary problem, ranging from mild respiratory illness to fatal acute respiratory distress syndrome. Most common manifestations are fever (89%) and cough (72%), while headache and arrhythmia are found in 28% and 17%, respectively. We aim to present a confirmed COVID-19 case presenting with both neurologic and cardiac manifestations. A 33-year-old Filipino male nurse initially consulted at the emergency room due to progressive diffuse headache, with associated localized seizures progressing to generalized tonic clonic seizure and arrhythmia. He had no coryza, cough, sore throat, and diarrhea. He was previously well and had no known co-morbidities or direct exposure to confirmed COVID-19 patients. Physical examination showed elevated blood pressure, tachycardia, and sensory and motor deficits in the left upper and lower extremities. Pertinent diagnostic test results included the detection of SARS-CoV-2 viral RNA via RT-PCR. Imaging studies demonstrated cortical venous thrombosis with hemorrhagic venous infarction in the right parietal lobe. Ground glass appearance on the middle lobe of the left lung was also evident. ECG showed supraventricular tachycardia. Prothrombin time, activated partial thromboplastin time, and D-dimer were all within the normal limits. Carotid massage was done. He was treated with anti-epileptics, anticoagulants, antiarrhythmics, antivirals, antibiotics, and supportive management. During the hospital stay, his symptoms resolved; he was discharged after 21 days. Follow-up done after 3 weeks revealed no recurrence of severe headache, seizure, or tachycardia. It is theorized that an interplay exists between ACE-2 tropism, systemic inflammation, cytokine storm, and hypoxemia in the background of COVID-19 infection. These mechanisms may lead to thrombosis and arrhythmia resulting to neurologic derangements and myocardial injury. Underlying mechanisms make the cerebro-cardiovascular systems vulnerable to the coronavirus disease 2019 infection. COVID-19 should therefore be part of the differential diagnoses in patients presenting with headache, seizures, and arrhythmias.
COVID-19 ; headache ; seizure ; supraventricular tachycardia

Objective: To determine the feasibility of using temporary permanent pacemaker (TPPM) in patients with high-degree atrioventricular block (AVB) after transcatheter aortic valve replacement (TAVR) as bridging strategy to reduce avoidable permanent pacemaker implantation. Methods: This is a prospective observational study. Consecutive patients undergoing TAVR at Beijing Anzhen Hospital and the First Affiliated Hospital of Zhengzhou University from August 2021 to February 2022 were screened. Patients with high-degree AVB and TPPM were included. Patients were followed up for 4 weeks with pacemaker interrogation at every week. The endpoint was the success rate of TPPM removal and free from permanent pacemaker at 1 month after TPPM. The criteria of removing TPPM was no indication of permanent pacing and no pacing signal in 12 lead electrocardiogram (EGG) and 24 hours dynamic EGG, meanwhile the last pacemaker interrogation indicated that ventricular pacing rate was 0. Routinely follow-up ECG was extended to 6 months after removal of TPPM. Results: Ten patients met the inclusion criteria for TPPM, aged (77.0±11.1) years, wirh 7 females. There were 7 patients with third-degree AVB, 1 patient with second-degree AVB, 2 patients with first degree AVB with PR interval>240 ms and LBBB with QRS duration>150 ms. TPPM were applied on the 10 patients for (35±7) days. Among 8 patients with high-degree AVB, 3 recovered to sinus rhythm, and 3 recovered to sinus rhythm with bundle branch block. The other 2 patients with persistent third-degree AVB received permanent pacemaker implantation. For the 2 patients with first-degree AVB and LBBB, PR interval shortened to within 200 ms. TPPM was successfully removed in 8 patients (8/10) at 1 month without permanent pacemaker implantation, of which 2 patients recovered within 24 hours after TAVR and 6 patients recovered 24 hours later after TAVR. No aggravation of conduction block or permanent pacemaker indication were observed in 8 patients during follow-up at 6 months. No procedure-related adverse events occurred in all patients. Conclusion: TPPM is reliable and safe to provide certain buffer time to distinguish whether a permanent pacemaker is necessary in patients with high-degree conduction block after TAVR.
Female ; Humans ; Atrioventricular Block/therapy* ; Feasibility Studies ; Transcatheter Aortic Valve Replacement ; Pacemaker, Artificial ; Bundle-Branch Block

Humans ; Cardiac Catheters ; Pacemaker, Artificial ; Arrhythmias, Cardiac