Cardiac arrest (CA) is a critical condition in the field of cardiovascular medicine. Despite successful resuscitation, patients continue to have a high mortality rate, largely due to post CA syndrome (PCAS). However, the injury and pathophysiological mechanisms underlying PCAS remain unclear. Experimental animal models are valuable tools for exploring the etiology, pathogenesis, and potential interventions for CA and PCAS. Current CA animal models include electrical induction of ventricular fibrillation (VF), myocardial infarction, high potassium, asphyxia, and hemorrhagic shock. Although these models do not fully replicate the complexity of clinical CA, the mechanistic insights they provide remain highly relevant, including post-CA brain injury (PCABI), post-CA myocardial dysfunction (PAMD), systemic ischaemia/reperfusion injury (IRI), and the persistent precipitating pathology. Summarizing the methods of establishing CA models, the challenges encountered in the modeling process, and the mechanisms of PCAS can provide a foundation for developing standardized CA modeling protocols.
Animals ; Disease Models, Animal ; Post-Cardiac Arrest Syndrome/physiopathology* ; Heart Arrest/physiopathology* ; Humans ; Ventricular Fibrillation/complications*

Objective: To compare the differences between CAS risk model and CHA₂DS₂-VASc risk score in predicting all cause death, thromboembolic events, major bleeding events and composite endpoint in patients with nonvalvular atrial fibrillation. Methods: This is a retrospective cohort study. From the China Atrial Fibrillation Registry cohort study, the patients with atrial fibrillation who were>18 years old were randomly divided into CAS risk score group and CHA₂DS₂-VASc risk score group respectively. According to the anticoagulant status at baseline and follow-up, patients in the 2 groups who complied with the scoring specifications for anticoagulation were selected for inclusion in this study. Baseline information such as age and gender in the two groups were collected and compared. Follow-up was performed periodically to collect information on anticoagulant therapy and endpoints. The endpoints were all-cause death, thromboembolism events and major bleeding, the composite endpoint events were all-cause death and thromboembolism events. The incidence of endpoints in CAS group and CHA₂DS₂-VASc group was analyzed, and multivariate Cox proportional risk model was used to analyze whether the incidence of the endpoints was statistically different between the two groups. Results: A total of 5 206 patients with AF were enrolled, average aged (63.6±12.2) years, and 2092 (40.2%) women. There were 2 447 cases (47.0%) in CAS risk score group and 2 759 cases (53.0%) in CHA₂DS₂-VASc risk score group. In the clinical baseline data of the two groups, the proportion of left ventricular ejection fraction<55%, non-paroxysmal atrial fibrillation, oral warfarin and HAS BLED score in the CAS group were lower than those in the CHA₂DS₂-VASc group, while the proportion of previous diabetes history and history of antiplatelet drugs in the CAS group was higher than that in the CHA₂DS₂-VASc group, and there was no statistical difference in other baseline data. Patients were followed up for (82.8±40.8) months. In CAS risk score group, 225(9.2%) had all-cause death, 186 (7.6%) had thromboembolic events, 81(3.3%) had major bleeding, and 368 (15.0%) had composite endpoint. In CHA₂DS₂-VASc risk score group, 261(9.5%) had all-cause death 209(7.6%) had thromboembolic events, 112(4.1%) had major bleeding, and 424 (15.4%) had composite endpoint. There were no significant differences in the occurrence of all-cause death, thromboembolic events, major bleeding and composite endpoint between anticoagulation in CAS risk score group and anticoagulation in CHA₂DS₂-VASc risk score group (log-rank P =0.643, 0.904, 0.126, 0.599, respectively). Compared with CAS risk score, multivariable Cox proportional hazards regression models showed no significant differences for all-cause death, thromboembolic events, major bleeding and composite endpoint between the two groups with HR(95%CI) 0.95(0.80-1.14), 1.00(0.82-1.22), 0.83(0.62-1.10), 0.96(0.84-1.11), respectively. All P>0.05. Conclusions: There were no significant differences between CAS risk model and CHA₂DS₂-VASc risk score in predicting all-cause death, thromboembolic events, and major bleeding events in Chinese patients with non-valvular atrial fibrillation.
Adolescent ; Anticoagulants ; Atrial Fibrillation/drug therapy* ; Cohort Studies ; Female ; Hemorrhage/complications* ; Humans ; Male ; Retrospective Studies ; Risk Assessment ; Stroke/epidemiology* ; Stroke Volume ; Thromboembolism/etiology* ; Ventricular Function, Left

Arrhythmogenic right ventricular cardiomyopathy (ARVC) is a kind of inherited cardio-myopathy, which is characterized by fibro-fatty replacement of right ventricular myocardium, leading to ventricular arrhythmia. However, rapid atrial arrhythmias are also common, including atrial fibrillation, atrial flutter and atrial tachycardia. Long term rapid atrial arrhythmia can lead to further deterioration of cardiac function. This case is a 51-year-old male. He was admitted to Department of Cardiology, Peking University Third Hospital with palpitation and fatigue after exercise. Electrocardiogram showed incessant atrial tachycardia. Echocardiography revealed dilation of all his four chambers, especially the right ventricle, with the left ventricular ejection fraction of 40% and the right ventricular hypokinesis. Cardiac magnetic resonance imaging found that the right ventricle was significantly enlarged, and the right ventricular aneurysm had formed; the right ventricular ejection fraction was as low as 8%, and the left ventricular ejection fraction was 35%. The patients met the diagnostic criteria of ARVC, and both left and right ventricles were involved. His physical activities were restricted, and metoprolol, digoxin, spironolactone and ramipril were given. Rivaroxaban was also given because atrial tachycardia could cause left atrial thrombosis and embolism. His atrial tachycardia converted spontaneously to normal sinus rhythm after these treatments. Since the patient had severe right ventricular dysfunction, frequent premature ventricular beats and non-sustained ventricular tachycardia on Holter monitoring, indicating a high risk of sudden death, implantable cardioverter defibrillator (ICD) was implanted. After discharge from hospital, physical activity restriction and the above medicines were continued. As rapid atrial arrhythmia could lead to inappropriate ICD shocks, amiodarone was added to prevent the recurrence of atrial tachycardia, and also control ventricular arrhythmia. After 6 months, echocardiography was repeated and showed that the left ventricle diameter was reduced significantly, and the left ventricular ejection fraction increased to 60%, while the size of right ventricle and right atrium decreased slightly. According to the clinical manifestations and outcomes, he was diagnosed with ARVC associated with arrhythmia induced cardiomyopathy. According to the results of his cardiac magnetic resonance imaging, the patient had left ventricular involvement caused by ARVC, and the persistent atrial tachycardia led to left ventricular systolic dysfunction.
Arrhythmogenic Right Ventricular Dysplasia/complications* ; Atrial Fibrillation ; Humans ; Male ; Middle Aged ; Stroke Volume ; Ventricular Function, Left ; Ventricular Function, Right

Anti-Arrhythmia Agents ; Brugada Syndrome/complications* ; Bundle-Branch Block/complications* ; Electrocardiography ; Humans ; Quinidine ; Ventricular Fibrillation

No abstract available.
Adult ; Brain/diagnostic imaging ; Bronchoscopy ; *Chromosomes, Human, Pair 9 ; Death, Sudden, Cardiac/*etiology ; Gene Duplication ; Humans ; Karyotyping ; Male ; Mental Disorders/*complications/genetics/pathology ; Tomography, X-Ray Computed ; Tracheomalacia/diagnostic imaging ; Ventricular Fibrillation/complications

BACKGROUNDPostresuscitation immune dysfunction contributes to the low survival rate after successful resuscitation, but its mechanism remains poorly understood. The purpose of this study was to investigate whether splenic regulatory T-cell (Treg) apoptosis was involved in the postresuscitation immune dysfunction.

METHODSThirty-eight pigs were randomly divided into sham-operated group (SHAM group, n = 8), 12 h post return of spontaneous circulation (ROSC) group, 24 h post-ROSC group, and 48 h post-ROSC group (n = 10 per group). A Wuzhishan miniature porcine model of 8-min ventricular fibrillation cardiac arrest (CA) was established. The apoptosis rates of Treg in the spleen were tested by flow cytometry; the expressions of forkhead/winged helix transcription factor (Foxp3) of Treg in the spleen were detected by real-time polymerase chain reaction; and the levels of interleukin-4 (IL-4), IL-10, and interferon gamma (IFN-γ) of Treg in the spleen were detected by enzyme-linked immunosorbent assay.

RESULTSThe apoptosis rates of Treg in all post-ROSC groups were significantly lower than that of SHAM group (7.7% ± 1.9%, 7.1% ± 1.8%, 6.2% ± 0.4% vs. 13.1% ± 1.6%; P < 0.05); the expression levels of Foxp3 and IL-10 were also decreased with the increase of apoptosis rates of Treg. Helper T-cells CD4+ lymphocyte subsets were significantly lower in the post-ROSC groups compared with SHAM group (29.1% ± 2.2%, 24.3% ± 2.2%, 24.1% ± 2.5% vs. 43.8% ± 4.5%; P < 0.01) at 12, 24, and 48 h after ROSC. Compared with SHAM group, the levels of IFN-γ (161.0 ± 12.9, 167.7 ± 10.5, 191.2 ± 7.7 vs. 7.6 ± 0.9 ng/L) and IL-4 (27.7 ± 6.2, 35.9 ± 3.5, 50.6 ± 6.1 vs. 13.3 ± 2.3 ng/L) and the ratio of IFN-γ/IL-4 (8.6 ± 2.3, 4.9 ± 0.4, 4.5 ± 0.9 vs. 0.8 ± 0.2) were all greatly elevated in all post-ROSC groups (P < 0.05).

CONCLUSIONSApoptosis rate of Treg was significantly decreased after CA, and thus the proportion of Treg was increased and the inhibitory effects were enhanced, which further led to the decrease of the amount of CD4+ T-cells. In addition, the T helper type 2/T helper type 1 (Th2/Th1) cell drift of Treg in the spleen caused postresuscitation immune dysfunction.

Animals ; Apoptosis ; physiology ; Cardiopulmonary Resuscitation ; Disease Models, Animal ; Enzyme-Linked Immunosorbent Assay ; Flow Cytometry ; Forkhead Transcription Factors ; metabolism ; Heart Arrest ; immunology ; metabolism ; Interferon-gamma ; metabolism ; Interleukin-4 ; metabolism ; Random Allocation ; Spleen ; cytology ; Swine ; Swine, Miniature ; T-Lymphocytes, Regulatory ; cytology ; metabolism ; physiology ; Ventricular Fibrillation ; complications ; metabolism

BACKGROUNDMorbidity and mortality after resuscitation largely depend on the recovery of brain function. Ventricular fibrillation cardiac arrest (VFCA) and asphyxial cardiac arrest (ACA) are the two most prevalent causes of sudden cardiac death. Up to now, most studies have focused on VFCA. However, results from the two models have been largely variable. So, it is necessary to characterize the features of postresuscitation cerebral metabolism of both models.

METHODSForty-four Wuzhishan miniature inbred pigs were randomly divided into three groups: 18 for VFCA group, ACA group, respectively, and other 8 for sham-operated group (SHAM). VFCA was induced by programmed electric stimulation, and ACA was induced by endotracheal tube clamping. After 8 min without treatment, standard cardiopulmonary resuscitation (CPR) was initiated. Following neurological deficit scores (NDS) were evaluated at 24 h after achievement of spontaneous circulation, cerebral metabolism showed as the maximum standardized uptake value (SUVmax) was measured by 18 F-fluorodeoxyglucose positron emission tomography/computed tomography. Levels of serum markers of brain injury, neuron specific enolase (NSE), and S100β were quantified with an enzyme-linked immunosorbent assay.

RESULTSCompared with VFCA group, fewer ACA animals achieved restoration of spontaneous circulation (61.1% vs. 94.4%, P < 0.01) and survived 24-h after resuscitation (38.9% vs. 77.8%, P < 0.01) with worse neurological outcome (NDS: 244.3 ± 15.3 vs. 168.8 ± 9.71, P < 0.01). The CPR duration of ACA group was longer than that of VFCA group (8.1 ± 1.2 min vs. 4.5 ± 1.1 min, P < 0.01). Cerebral energy metabolism showed as SUVmax in ACA was lower than in VFCA (P < 0.05 or P < 0.01). Higher serum biomarkers of brain damage (NSE, S100β) were found in ACA than VFCA after resuscitation (P < 0.01).

CONCLUSIONSCompared with VFCA, ACA causes more severe cerebral metabolism injuries with less successful resuscitation and worse neurological outcome.

Animals ; Asphyxia ; complications ; physiopathology ; Brain ; metabolism ; Cardiopulmonary Resuscitation ; Heart Arrest ; metabolism ; pathology ; therapy ; Positron-Emission Tomography ; Swine ; Ventricular Fibrillation ; metabolism ; pathology ; therapy

BACKGROUNDMajority of the research on cardiac arrest (CA) have focused on post-CA brain injury and myocardial dysfunction, the renal dysfunction and acute kidney injury (AKI) in other critical illnesses after CA have not been well described. This study was designed to assess AKI with renal Doppler and novel AKI biomarkers in a swine model of ventricular fibrillation cardiac arrest (VFCA).

METHODSThirty healthy piglets were divided into VFCA group (n = 22) and Sham group (n = 8) in a blinded manner. Mean arterial pressure, heart rate, and cardiac output were recorded continuously. Cardiac arrest (CA) was induced by programmed electric stimulation in the VFCA group, and then cardiopulmonary resuscitation was performed. Twenty piglets returned of spontaneous circulation (ROSC) and received intensive care. Blood and urine samples were collected for AKI biomarkers testing, and Color Doppler flow imaging was performed at baseline, 6 h, 12 h, and 24 h, respectively after ROSC. At ROSC 24 h, the animals were sacrificed and a semi-quantitative evaluation of pathologic kidney injury was performed.

RESULTSIn the VFCA group, corrected resistive index (cRI) increased from 0.47 ± 0.03 to 0.64 ± 0.06, and pulsatility index (PI) decreased from 0.82 ± 0.03 to 0.68 ± 0.04 after ROSC. Cystatin C (CysC) in both serum and urine samples increased at ROSC 6 h, but neutrophil gelatinase-associated lipocalin (NGAL) in serum increased to 5.34 ± 1.68 ng/ml at ROSC 6 h, and then decreased to 3.16 ± 0.69 ng/ml at ROSC 24 h while CysC increasing constantly. According to the renal histopathology, 18 of 20 animals suffered from kidney injury. The grade of renal injury was highly correlated with RI, cRI, NGAL, and CysC. Linear regression equation was established: Grade of renal injury = 0.002 × serum CysC + 6.489 × PI + 4.544 × cRI - 8.358 (r2 = 0.698, F = 18.506, P < 0.001).

CONCLUSIONSAKI is common in post-CA syndrome. Renal Doppler and novel AKI biomarkers in serum and urine are of significant importance as early predictors of post-CA AKI.

Acute Kidney Injury ; blood ; etiology ; Animals ; Biomarkers ; blood ; Cystatin C ; blood ; Disease Models, Animal ; Female ; Heart Arrest ; blood ; complications ; Lipocalins ; blood ; Male ; Swine ; Ultrasonography, Doppler ; methods ; Ventricular Fibrillation ; blood ; complications

Adult ; Female ; Humans ; Hyperlipoproteinemia Type II ; complications ; Ventricular Fibrillation ; complications

Female ; Humans ; Middle Aged ; Propofol ; therapeutic use ; Pulmonary Embolism ; complications ; Ventricular Fibrillation ; drug therapy ; etiology