In-hospital Ventricular Arrhythmias Research Articles

Stratification of Early Arrhythmic Risk in Patients Admitted for Acute Coronary Syndrome: The Role of the Machine Learning-Derived "PRAISE Score".

The PRAISE (PRedicting with Artificial Intelligence riSk aftEr acute coronary syndrome) score is a machine learning-based model for predicting 1-year adverse cardiovascular or bleeding events in patients with acute coronary syndrome (ACS). Its role in predicting arrhythmic complications in ACS remains unknown. Atrial fibrillation (AF) and ventricular arrhythmias (VA) were recorded by continuous electrocardiographic monitoring until discharge in a cohort of 365 participants with ACS prospectively enrolled. We considered two separate timeframes for VA occurrence: ≤ 48 and > 48 h. The objective was to evaluate the ability of the PRAISE score to identify ACS patients at higher risk of in-hospital arrhythmic complications. ROC curve analysis indicated a significant association between PRAISE score and risk of both AF (AUC 0.89, p = 0.0001; optimal cut-off 5.77%) and VA (AUC 0.69, p = 0.0001; optimal cut-off 2.17%). Based on these thresholds, high/low AF PRAISE score groups and high/low VA PRAISE score groups were created, respectively. Patients with a high AF PRAISE score more frequently developed in-hospital AF (19% vs. 1%). Multivariate analysis showed a high AF PRAISE score risk as an independent predictor of AF (HR 4.30, p = 0.016). Patients with high VA PRAISE scores more frequently developed in-hospital VA (25% vs. 8% for VA ≤ 48 h; 33% vs. 3% for VA > 48 h). Multivariate analysis demonstrated a high VA PRAISE score risk as an independent predictor of both VA ≤ 48 h (HR 2.48, p = 0.032) and VA > 48 h (HR 4.93, p = 0.014). The PRAISE score has a comprehensive ability to identify with high specificity those patients at risk for arrhythmic events during hospitalization for ACS.

Prognostic Value of Ultra-Short Heart Rate Variability Measures Obtained from Electrocardiogram Recordings of Hospitalized Patients Diagnosed with Non-ST-Elevation Myocardial Infarction.

Background: Myocardial infarction (MI) is a common emergency with high rates of morbidity and mortality. Current risk stratification scores for non-ST-elevation MI (NSTEMI) use subjective or delayed information. Heart rate variability was shown to correlate with prognosis following MI. This study aimed to evaluate ultra-short heart rate variability (usHRV) as a prognostic factor in NSTEMI patients. Methods: A retrospective analysis was performed on 183 NSTEMI patients admitted to Rambam Health Care Campus in 2014. usHRV measures, including the standard deviation of normal-to-normal intervals (SDNN) and root mean square of successive differences (RMSSD), were calculated. Logistic regression assessed whether clinical, laboratory, or usHRV parameters predicted severe in-hospital complications like heart failure (HF), atrial flutter/fibrillation (AFL/AF), ventricular tachycardia/fibrillation (VT/VF), and atrioventricular block (AVB). Both Cox and logistic regression were used for survival analysis. Results: Of 183 patients (71.6% male, mean age 67.1), 35 (19%) died within 2 years. In-hospital complications included 39 cases (21.3%) of HF, 3 cases (1.6%) of VT/VF, and 9 cases (4.9%) of AVB. Lower usHRV was significantly associated with higher mortality at 2 years and showed marginal significance at 90 days and 1 year. Increased usHRV was linked to a higher risk of in-hospital ventricular arrhythmia (VT/VF). Conclusions: Overall, this study is in agreement with previous research, showing a correlation between low usHRV and a higher mortality risk. However, the association between usHRV and the risk of VT/VF demands further investigation. More expansive prospective studies are needed to strengthen the observed associations.

Dexmedetomidine vs. propofol on arrhythmia in cardiac surgery: a meta-analysis of randomized controlled trials.

Dexmedetomidine (DEX) and propofol are popular anesthetics, but it remains unknown whether DEX reduces the incidence of arrhythmias compared with propofol after cardiac surgery. We performed a comprehensive search for RCTs (Randomized Controlled Trials) that compared the incidence of arrhythmias between DEX and propofol in adults who had undergone cardiac surgery across three databases (PubMed, Embase, the Cochrane Library), and ClinicalTrials.gov up to October 3, 2023. The primary outcome was ventricular arrhythmias, the secondary outcomes were bradycardia and atrial fibrillation (AF). Our analysis included 7 RCTs with 1,004 patients (mean age: 64.37, male: 71.11%) undergoing cardiac surgery, and the incidence of in-hospital arrhythmia was 22.01% (ventricular arrhythmias 2.75%, bradycardia 3.33%, AF 18.63%). Perioperative or postoperative use of DEX reduced the incidence of in-hospital ventricular arrhythmias [Odds Ratio (OR) 0.14, 95% Confidence Interval (CI) 0.03-0.66], but increased the risk of in-hospital bradycardia (OR 2.88, 95% CI 1.02-8.17) compared with propofol. The trial sequence analysis verified the adequacy of sample size and robustness of the ventricular arrhythmias and bradycardia. There was no significant reduced incidence of the use of DEX in the incidence of AF (OR 0.69, 95% CI 0.36-1.29). The GRADE assessment indicated a high certainty for ventricular arrhythmias and bradycardia and a moderate certainty for AF. Our findings suggested the use of DEX reduces in-hospital ventricular arrhythmias but increases bradycardia incidence compared to propofol in adult patients undergoing cardiac surgery. Further studies are needed to assess the impact of dexmedetomidine on atrial fibrillation compared to propofol. http://www.crd.york.ac.uk/prospero/ PROSPERO, identifier (CRD42023482193).

Abstract 13790: Efficacy of Stellate Ganglion Block for Refractory Ventricular Arrhythmias: An Updated Systematic Review

Background: Stellate ganglion block (SGB) has emerged as an alternative approach to refractory ventricular arrhythmias (VAs). However, data on the outcome of SGB for refractory VAs are limited. Objective: This study aimed to assess the in-hospital efficacy of SGB in refractory VAs. Method: A systematic search was performed in MEDLINE and EMBASE according to the PRISMA guidelines from July 2017 to October 2022. Studies reporting the characteristics of in-hospital VAs before and after the SGB were included. Studies that had missing outcomes were excluded. Results: Of 515 publications reviewed, 162 patients (60.6 ± 13.6 years of age, 81.5% male) were included across 27 studies. Amongst, 103 patients (63.6%) had ischemic cardiomyopathy, and the mean ejection fraction was 29.8 ± 12.7%. Prior to the SGB procedure, 100 patients (61.7%) required two or more anti-arrhythmic medications control. Following SGB, there was a significant 92% reduction of VAs episodes from 13.9 ± 18.5 to 0.9 ± 2.1 (p<0.01) during the hospitalization (31±35 days). Of the reported patients, 46.5% remained free of VAs, and 53.5% had recurrences before discharge. Among 61 patients who required additional neuromodulation after SGB in the same hospitalization, 32 patients (52.5%) received repeated SGB, 15 patients (24.6%) underwent surgical sympathectomy, and 14 patients (23%) underwent catheter ablation. Of the reported patients, 75.4% of patients survived throughout the hospital course. Conclusion: SGB significantly reduced VAs episodes in patients with refractory VAs during hospitalization. More than three-quarters of the patients survived following the SGB for refractory VAs. This highlights the potential effective role of SGB in managing refractory VAs. Figure Change in Ventricular Arrhythmias Burden after Stellate Ganglion Block

Predictors and outcome of electrical storm-induced cardiogenic shock.

Limited information is available about the short- and long-term outcomes in electrical storm (ES)-induced cardiogenic shock (CS) and its predictors. This is a retrospective, single-centre cohort study of consecutive patients with ES admitted to the Cardiac Intensive Care Unit between 2015 and 2020. The proportion of ES patients who developed CS was adjudicated, and clinical predictors of in-hospital ventricular arrhythmia (VA)-related mortality and 1-year all-cause mortality were investigated. Of the 214 patients with ES, 33.6% developed CS. Left-ventricular ejection fraction, admission lactate, absence of an implantable cardioverter defibrillator, and admission central venous pressure were independently associated with development of CS (P < 0.03 for all). Based on these variables, a FLIC score was developed (https://riskcalc.org/FLICscore/) to predict ES-induced CS [area under the curve (AUC) = 0.949, with AUC = 0.954 in a validation cohort, both P < 0.001]. Patients who developed CS had a 11.3-fold [95% confidence interval (CI) 2.7-12.8] increased odds for in-hospital VA-related mortality and 9.4-fold (95% CI 4.0-22.4) increased odds for in-hospital all-cause mortality. A FLIC score above 0.62 was associated with a 6.2- and 5.8-fold increased odds for respectively similar endpoints. Patients with ES-induced CS received more treatment modalities to manage the ES (4.5 ± 1.8 vs. 2.3 ± 1.2, P < 0.001) and had longer length of stay [14 (8-27) vs. 8 (5-13), P < 0.001] than patients without CS. Interestingly, if patients with ES-induced CS survived to discharge, their outcomes were similar to those without CS at 1 year. Cardiogenic shock in ES is a frequent and potentially life-threatening complication with high short-term mortality. A novel risk score could identify patient at risk, generating a potential for early risk-based interventions.

Impact of Atrial Fibrillation and/or Flutter on in-Hospital Management and Outcomes in Non-ST Elevation Acute Coronary Syndromes

Abstract Funding Acknowledgements Type of funding sources: None. Background Atrial fibrillation is the most common arrhythmia in patients with acute coronary syndromes, and it is increasing in prevalence considering the aging of populations and the overlap of risk factors. It was reported by earlier studies that atrial fibrillation and/or flutter portend worse prognosis in patients with acute coronary syndromes. Yet there is no data from Iraq regarding impact of these arrhythmias on prognosis of patients with NSTE-ACS. Purpose This study aimed to evaluate the impact of pre-existing or new onset atrial fibrillation and/or flutter on in-hospital management and outcomes in an Iraqi cohort of patients with NSTE-ACS. Methods Patients with NSTE-ACS were prospectively included. GRACE risk score was calculated by the investigator with subsequent classification into low, intermediate and high GRACE risk class. Then the patients were classified into those who had pre-existing or new onset atrial fibrillation and/or atrial flutter (Patients with AF) group versus those with no atrial fibrillation nor atrial flutter (non-AF group). Results N=200, among whom AF was evident in 8.5%. Patients with AF were older (64.47±10.02 vs 58.22±11.79 years, p=0.025), they were females in 35.3% vs 29% in non-AF counterparts, p=0.58. There were no statistical differences between the two groups regarding presence of hypertension, diabetes, prior history of ischemic heart disease (IHD) nor family history of IHD, however, AF group were smokers in 11.8% vs 36.6% in non-AF group, p=0.039. Patients with AF reported dyspnoea at presentation in 47.1% vs 27.9%. Patients with AF were at high GRACE risk class at presentation in 76.5% vs 28.4% in non-AF group, p&amp;lt;0.001. Patients with AF were referred less for catheterisation during index hospitalisation compared to non-AF counterparts (35.3% vs 72.1%, p=0.002). There were no statistical differences between the two groups regarding days to catheterisation nor days of hospitalisation. There were no statistical differences between the two groups regarding developing in-hospital acute heart failure, cardiogenic shock, persistent ischemic chest pain, nor in-hospital ventricular life-threatening arrhythmia (VT, VF or Complete heart block), however, patients with AF developed higher in-hospital stroke (5.9% vs 0.5%, p=0.034) and higher in-hospital death (11.8% vs 1.6%, p=0.011). Conclusion Patients with NSTE-ACS and concurrent AF presented at higher risk class at presentation and higher in-hospital stroke and in-hospital death compared to patients with no AF, yet those patients were catheterised less frequently during index hospitalisation. Larger studies are needed to assess the impact of AF on longer term prognosis in the setting of NSTE-ACS. More attention should be paid for this high-risk category of NSTE-ACS patients with more emphasis on following evidence-based guidelines regarding decision and timing of catheterisation in order to improve their outcomes.

Risk factors and prediction nomogram model for 1-year readmission for major adverse cardiovascular events in patients with STEMI after PCI.

To identify risk factors and develop a risk-prediction nomogram model for 1-year readmission due to major adverse cardiovascular events (MACEs) in patients with acute ST-segment elevation myocardial infarction (STEMI) after primary percutaneous coronary intervention (PCI). This was a single-center, retrospective cohort study. A total of 526 eligible participants were enrolled, which included 456 non-readmitted and 70 readmitted patients. Multivariate logistical regressions were performed to identify the independent risk factors for readmission, and a prediction nomogram model was developed based on the results of the regression analysis. The receiver operating characteristic curve, Hosmer-Lemeshow test, calibration plot, and decision curve analysis (DCA) were used to evaluate the performance of the nomogram. Female (OR = 2.426; 95% CI: 1.395-4.218), hypertension (OR = 1.898; 95% CI: 1.100-3.275), 3-vessel disease (OR = 2.632; 95% CI: 1.332-5.201), in-hospital Ventricular arrhythmias (VA) (OR = 3.143; 95% CI: 1.305-7.574), peak cTnI (OR = 1.003; 95% CI: 1.001-1.004) and baseline NT-proBNP (OR = 1.001; 95% CI: 1.000-1.002) were independent risk factors for readmission (all P < 0.05). The nomogram exhibited good discrimination with the area under the curve (AUC) of 0.723, calibration (Hosmer-Lemeshow test; χ2 = 15.396, P = 0.052), and clinical usefulness. Female gender, hypertension, in-hospital VA, 3-vessel disease, baseline NT-proBNP, and peak cTnI were independent risk factors for readmission. The nomogram helped clinicians to identify the patients at risk of readmission before their hospital discharge, which may help reduce readmission rates.

Association between Plasma Thiol Parameters and Troponin Levels in Patients with Acute Coronary Syndrome and Prediction of In-Hospital Ventricular Arrhythmia.

ResumoFundamento As arritmias ventriculares (AVs) são a principal causa de mortalidade e morbidade hospitalar em pacientes com síndrome coronariana aguda (SCA) e sua relação com o tiol é desconhecida.Objetivo Investigar a relação entre os níveis plasmáticos de tióis e os níveis de troponina em pacientes com SCA e estimar o desenvolvimento de AV intra-hospitalar durante a internação.Método O estudo incluiu 231 pacientes consecutivos com SCA com supradesnivelamento do segmento ST (SCA-SDST) e pacientes com SCA sem supradesnivelamento do segmento ST (SCA-SSDST). Após a aplicação dos critérios de exclusão, 191 pacientes foram incluídos na análise estatística. Os pacientes foram classificados em dois grupos: grupo SCA-SDST (n=94) e grupo SCA-SSDST (n=97). Os níveis plasmáticos de tiol, dissulfeto e troponina foram medidos e a razão de troponina para tiol nativo (RTTN) foi calculada. Considerou-se estatisticamente significativo um valor de p bilateral inferior a 0,05.Resultados Tiol nativo plasmático, tiol total, dissulfeto e suas razões foram semelhantes entre os grupos. A RTTN se mostrou significativamente maior no grupo SCA-SDST em comparação com o grupo SCA-SSDST. Houve correlação negativa significativa entre os níveis de troponina e tiol. Verificou-se que o tiol nativo é preditor independente do desenvolvimento de AV em pacientes com SCA-SDST e em todos os pacientes com SCA. Verificou-se que o RTTN é preditor independente do desenvolvimento de AV em pacientes com SCA-SSDST e em todos os pacientes com SCA.Conclusão Os níveis plasmáticos de tiol podem ser usados para identificar pacientes com alto risco de desenvolvimento de AV intra-hospitalar em pacientes com SCA. A correlação entre os níveis de troponina e tiol pode sugerir que os tióis possam ser marcadores importantes para o diagnóstico e prognóstico da SCA com a ajuda de estudos futuros.

Severe Acute Respiratory Syndrome Coronavirus 2: The Importance of Prompt Detection of Cardiovascular Involvement

Increased morbidity and mortality are associated with coronavirus disease 2019 (COVID-19) when there is cardiovascular (CV) involvement. Due to the absence of prospective, well-designed, controlled studies, the exact mechanism responsible for cardiac injury among patients with COVID-19 remains uncertain. However, possible mechanisms described in observational studies can be considered. Non-ischemic events and ischemic myocardial involvement are the two main pathophysiological mechanisms of acute cardiac injury in COVID-19 patients. Non-ischemic myocardial injury is probably predominant and is secondary to multiple pathological mechanisms. Cardiac involvement is relatively common among hospitalized patients with COVID-19 and is associated with a greater risk of in-hospital mortality and ventricular arrhythmias. There was also a high and significantly positive linear correlation between troponin T and plasma high-sensitivity C-reactive protein levels. It is important to promptly detect CV involvement to avoid increased mortality in these patients. These findings highlight the importance of clinical surveillance and laboratory testing of serum troponin levels to ensure appropriate early identification and proceed with appropriate treatment. This should apply to patients with/without prior CV involvement. There are several possible mechanisms of myocardial tissue damage and the exact mechanisms involved need to be explored in well-designed studies.

Implantable Cardioverter Defibrillator Utilization and Mortality Among Patients ≥65 Years of Age With a Low Ejection Fraction After Coronary Revascularization

The purpose of this analysis was to assess implantable cardioverter-defibrillator (ICD) utilization and its association with mortality among patients ≥65 years of age after coronary revascularization. Patients in the National Cardiovascular Database Registry Chest Pain-Myocardial Infarction (MI) Registry who presented with MI from January 2, 2009 to December 31, 2016, had a left ventricular ejection fraction ≤35% and underwent in-hospital revascularization (10,014 percutaneous coronary intervention (PCI) and 1,647 coronary artery bypass grafting (CABG)) were linked with Medicare claims to determine rates of 1-year ICD implantation. The association between ICD implantation and 2-year mortality was assessed. Of 11,661 included patients, an ICD was implanted in 1,234 (10.6%) within 1 year of revascularization (1,063 (10.6%) PCI and 171 (10.4%) CABG). Among PCI-treated patients, in-hospital ventricular arrhythmia (adjusted hazard ratio [aHR] 1.60, 95% confidence interval [CI] 1.34 to 1.92), 2-week cardiology follow-up (aHR 1.48, 95% CI 1.29 to 1.70), readmission for heart failure (aHR 3.21, 95% CI 2.73 to 3.79), and readmission for MI (aHR 2.18, 95% CI 1.66 to 2.85) were positively associated with ICD implantation. Among CABG-treated patients, in-hospital ventricular arrhythmia (aHR 2.33, 95% CI 1.39 to 3.91), and heart failure readmission (aHR 3.14, 95% CI 1.96 to 5.04) were positively associated with ICD implantation. Women were less likely to receive an ICD, regardless of the revascularization strategy. ICD implantation was associated with lower 2-year all-cause mortality (aHR 0.74, 95% CI 0.63 to 0.86). In conclusion, only 1 in 10 Medicare patients with low ejection fraction received an ICD within 1 year after revascularization. Contact with the healthcare system after discharge was associated with higher likelihood of ICD implantation. ICD implantation was associated with lower mortality following revascularization for MI.

Ventricular Arrhythmias in Patients with Spontaneous Coronary Artery Dissection

Spontaneous coronary artery dissection (SCAD) is an increasingly recognized cause of acute coronary syndrome in young women, with a wide clinical spectrum of severity. Ventricular arrhythmia (VA) can occur and worsen prognosis. The current study compared in-hospital and follow-up adverse cardiovascular events in patients with and without VA at presentation. Eighty-three cases of SCAD were collected retrospectively from 4 Gulf countries (KSA, UAE, Kuwait, and Bahrain) during the period from January 2011 to December 2017. We divided the patients into 2 groups: those with and without VA at presentation. VA was defined as ventricular tachycardia and/or ventricular fibrillation. In-hospital (recurrent VA, cardiogenic shock, death, implantable cardioverter-defibrillator placement, dissection extension) and follow-up (MI, de novo SCAD, death, spontaneous superior mesenteric artery dissection) events were compared among the 2 groups. The median age of patients in the study was 44 (37-55) years. Forty-two (51%) were women. VA occurred in 10 (12%) patients in the first 24-hour of hospitalization, and 5 (50%) of those patients had recurrent in-hospital VA. Among those with recurrent VA, 1 died during hospitalization and 1 died within the first year following hospital discharge. In-hospital adverse cardiovascular events were significantly more frequent for patients with SCAD who presented with VA. However, follow-up events were not statistically significant between those with and without VA at presentation.

In-hospital ventricular arrhythmia in heart failure patients: 7year follow-up of the multi-centric HEARTS registry.

AimsThe aim of this study was to determine the incidence, predictors, and short‐term and long‐term outcomes associated with in‐hospital sustained ventricular tachycardia (VT) and ventricular fibrillation (VF) collectively termed ventricular arrhythmia (VA) in the heart failure (HF) patients.Methods and resultsThe HEart function Assessment Registry Trial in Saudi Arabia (HEARTS registry) is a prospective national registry of patients with chronic HF from18 tertiary care hospitals across Saudi Arabia. Diagnosis of HF was in accordance with American Heart Association/European Society of Cardiology definition criteria. The registry had enrolled 2610 HF patients during the 14 month recruitment period between October 2009 and December 2010. Occurrence of in‐hospital cardiac events, prognosis, and outcome were monitored during the 7 year follow‐up period. The incidence of in‐hospital VA in HF was 4.2%. VA was more common among men, and mean age was lesser than non‐VA patients (58.5 ± 16: 61.5 ± 15 years; P = 0.042). Smoking and family history of cardiomyopathy were significant risk factors of VA. Previous history of arrhythmia, ST elevated myocardial infarction, infections, and hypotension remained significant predictors of in‐hospital VA associated with three to seven times more risk. Patients with VA had higher rates of in‐hospital events like recurrent HF, haemodialysis, shock, sepsis, major bleeding, intra‐aortic balloon pump, and stroke compared with those without VA, all being highly significant (P < 0.001). After adjustment for age, gender, and co‐morbidities, in‐hospital VA increased the risk of cardiogenic shock by 24 times, dialysis and major bleeding by 10 times, and recurrent congestive HF and pacing by five times. Survival analysis showed that all‐cause mortality was significantly higher in the VA patients (P < 0.001). Presence of VA increased in‐hospital and 1 month mortality to 23 and 17 times, respectively.ConclusionsLower mean age of VA complicated HF patients is a matter of concern in the Saudi population. HF associated with VA increased in‐hospital events and all‐cause mortality indicating poor prognosis and survival. These findings enable risk stratification and reflect on the importance of early recognition of the clinical markers and predictors of VA prompting immediate management.

Electrocardiographic measures of ventricular repolarization dispersion and arrhythmic outcomes among ST elevation myocardial infarction patients with pre-infarction angina undergoing primary percutaneous coronary intervention.

Arrhythmias are considered one of the major causes of death in ST elevation myocardial infarction (STEMI), particularly in the early in-hospital phase. Pre-infarction angina (PIA) has been suggested to have a protective role. To study the difference in acute electrocardiographic findings between STEMI patients with and without PIA and to assess the in-hospital arrhythmias in both groups. We prospectively enrolled 238 consecutive patients with STEMI. Patients were divided into two groups: those with or without PIA. ECG data recorded and analyzed included ST-segment resolution (STR) at 90min, corrected QT interval (QTc) and dispersion (QTD), T-peak-to-T-end interval (Tp-Te), and dispersion and Tp-Te/QT ratio. In-hospital ventricular arrhythmias encountered in both groups were recorded. Predictors of in-hospital arrhythmias were assessed among different clinical and electrocardiographic parameters. Of the 238 patients included, 42 (17%) had PIA and 196 (83%) had no PIA. Patients with PIA had higher rates of STR (p<0.0001), while patients with no PIA had higher values of QTc (p=0.006), QTD (p=0.001), Tp-Te interval (p=0.001), Tp-Te dispersion (p<0.0001), and Tp-Te/QT ratio (p=0.01) compared to those with angina preceding their incident infarction (PIA). This was reflected into significantly higher rates of in-hospital arrhythmias among patients with no PIA (20% vs. 7%, p=0.04). Furthermore, longer Tp-Te interval and higher Tp-Te/QT ratio independently predicted in-hospital ventricular arrhythmias. Pre-infarction angina patients had better electrocardiographic measures of repolarization dispersion and encountered significantly less arrhythmic events compared to patients who did not experience PIA.

Incidence and effect of early postoperative ventricular arrhythmias after congenital heart surgery

Postoperative arrhythmias after pediatric congenital heart disease (CHD) surgery are a known cause of morbidity and are associated with mortality. A comprehensive evaluation of early postoperative ventricular arrhythmias (VAs) after CHD surgery has not been reported. We sought to determine the incidence of in-hospital VAs after CHD surgery and assess the clinical relevance of this arrhythmia during the postoperative hospital course. Patients undergoing CHD surgery at our center from September 2007 through December 2016 were prospectively enrolled. Univariate and multivariate analysis was used to assess the association between postoperative VAs and in-hospital mortality, adjusting for postoperative extracorporeal membrane oxygenation and stage 1 single ventricle palliation operations. A total of 2503 postoperative courses in 1835 patients were included. In all, 464 (18.5%) had VAs, of whom 135 (29.1%) received treatment. Monomorphic ventricular tachycardia was the most frequently treated ventricular arrhythmia (TVA; n=91 [62.3%]). TVAs were associated with increased postoperative extracorporeal membrane oxygenation (13.3% vs 5.5%; P < .001) and in-hospital mortality (14.9% vs 4.0%; P < .001). In multivariate analysis, TVA was an independent risk factor for in-hospital mortality (adjusted odds ratio 2.44; 95% confidence interval 1.21-4.92). Early postoperative VAs after CHD surgery are more common than previously reported. Postoperative VAs are associated with increased in-hospital mortality, and the subgroup of TVAs is an independent risk factor for in-hospital mortality.

Effect of Dynamic Potassium Change on In-Hospital Mortality, Ventricular Arrhythmias, and Long-Term Mortality in STEMI.

We evaluated the effect of serum potassium (K) deviation on in-hospital and long-term clinical outcomes in patients with ST-segment elevation myocardial infarction who were normokalemic at admission. A total of 2773 patients with an admission serum K level of 3.5 to 4.5 mEq/L were retrospectively analyzed. The patients were categorized into 3 groups according to their K deviation: normokalemia-to-hypokalemia, normokalemia-to-normokalemia, and normokalemia-to-hyperkalemia. In-hospital mortality, long-term mortality, and ventricular arrhythmias rates were compared among the groups. In a hierarchical multivariable regression analysis, the in-hospital mortality risk was higher in normokalemia-to-hypokalemia (odds ratio [OR] 3.03; 95% confidence interval [CI], 1.72-6.82) and normokalemia-to-hyperkalemia groups (OR 2.81; 95% CI, 1.93-4.48) compared with the normokalemia-to-normokalemia group. In a Cox regression analysis, long-term mortality risk was also higher in normokalemia-to-hypokalemia (hazard ratio [HR] 3.78; 95% CI, 2.07-7.17) and normokalemia-to-hyperkalemia groups (HR, 2.97; 95% CI, 2.10-4.19) compared with the normokalemia-to-normokalemia group. Ventricular arrhythmia risk was also higher in normokalemia-to-hypokalemia group (OR 2.98; 95% CI, 1.41-5.75) compared with normokalemia-to-normokalemia group. The current study showed an increased in-hospital ventricular arrhythmia and mortality and long-term mortality rates with the deviation of serum K levels from normal ranges.

In-hospital major arrhythmias, arrhythmic death and resuscitation after successful primary percutaneous intervention for acute transmural infarction: a retrospective single-centre cohort study

BackgroundTransmural acute myocardial infarction (AMI) is associated with a high risk for ventricular arrhythmia before, during and after treatment. Consequently, it is recommended that patients diagnosed with transmural AMI be monitored in a cardiac care unit (CCU) so life-threatening arrhythmias can be treated promptly. We examined the incidence and timing of in-hospital malignant ventricular arrhythmias, sudden cardiac or arrhythmic death (SCD/AD) and resuscitation requirements in patients with transmural AMI recovering from percutaneous coronary intervention (PCI) undertaken within 12 h of symptom onset and without antecedent thrombolysis.MethodsThis was a retrospective cohort study using the Duisburg Heart Center (Germany) cardiac patient registry. In total, 975 patients met the inclusion criteria. The composite endpoint was post-PCI ventricular fibrillation or tachycardia, SCD/AD or requirement for resuscitation. We compared the demographic and clinical characteristics of patients who met the composite endpoint with those who did not, recorded the timing of endpoint episodes, and used multivariable logistic regression analysis to identify factors associated with the endpoint criteria.ResultsThere was no significant difference in the length of CCU or hospital stay between the groups. In-hospital mortality was 6.5%, and the composite endpoint was met in 7.4% of cases. Malignant ventricular tachyarrhythmia occurred in 2.8% of the patients, and SCD/AD occurred in 0.3% of the cases. There was a biphasic temporal distribution of endpoint events; specifically, 76.7% occurred < 96 h after symptom onset, and 12.6% occurred 240–360 h after symptom onset. Multivariable regression analysis identified positive associations between an endpoint episode and the following: age (odds ratio [OR] 1.03, 95% confidence interval [CI] 1.01–1.05] per year); left ventricular ejection fraction (LVEF) < 30% (OR 3.66, 95% CI 1.91–6.99); peak serum creatine phosphokinase concentration (OR 1.01, 95% CI 1.00–1.02 per 100 U/dl); leucocytosis (OR 1.86, 95% CI 1.04–3.32), and coronary thrombus (OR 1.85, 95% CI 1.04–3.27).ConclusionsMost post-PCI malignant ventricular arrhythmias, SCD/AD and resuscitation episodes occurred within 96 h of transmural AMI (76.7%). A substantial minority (12.6%) of these events arose 240–360 h after symptom onset. Further study is needed to establish the influence of age, LVEF < 30%, peak serum creatine phosphokinase concentration, leucocytosis and coronary thrombus on post-PCI outcomes after transmural AMI.

Tpeak-to-Tend/QT is an independent predictor of early ventricular arrhythmias and arrhythmic death in anterior ST elevation myocardial infarction patients.

The aim of our study was to analyse the markers of transmural dispersion of ventricular repolarization, especially Tpeak-to-Tend and Tpeak-to-Tend /QT ratio, in patients with anterior ST elevation myocardial infarction on admission and to evaluate their association with in-hospital life-threatening arrhythmias and mortality. A total of 223 consecutive patients with anterior wall ST elevation myocardial infarction admitted to our Division of Cardiology between January 2010 and December 2012 were prospectively evaluated. A standard electrocardiogram was obtained on admission and then analysed. The primary end point was constituted by in-hospital ventricular arrhythmias and arrhythmic death. At univariate analysis heart rate (odds ratio = 1.03; 95% confidence intervals 1.006-1.05; p=0.001), maximal ST elevation (odds ratio =1.25; 95% confidence intervals 1.10-1.43; p=0.0001), QTc Bazett (odds ratio = 1.01; 95% confidence intervals 1.006-1.02; p=0.002), QT dispersion (odds ratio = 1.02; 95% confidence intervals 1.002-1.04; p=0.02) and both Tpeak-to-Tend and Tpeak-to-Tend/QT (odds ratio = 1.02; 95% confidence intervals 1.01-1.03; p<0.0001 and OR = 1.07; 95% confidence intervals 1.03-1.11; p<0.0001 respectively) were significantly associated with ventricular arrhythmias and arrhythmic mortality. Of note, Tpeak-to-Tend /QT remained a predictor of early ventricular arrhythmias and arrhythmic death (odds ratio = 1.04; 95% confidence intervals 1.003 - 1.10; p=0.03) independently from heart rate and maximal ST elevation. Receiver operating characteristic curve analysis showed that Tpeak-to-Tend /QT values <0.31 had a predictive negative value of 92% for the prediction of the composite outcome. Tpeak-to-Tend /QT was an independent predictor of early ventricular arrhythmias and arrhythmic mortality in patients with anterior ST elevation myocardial infarction. Especially, Tpeak-to-Tend /QT <0.31 may identify a subgroup of ST elevation myocardial infarction patients with low risk of early arrhythmias and arrhythmic death.

The association between normal-range admission potassium levels in Israeli patients with acute coronary syndrome and early and late outcomes.

Abnormal serum potassium levels are associated with an increased risk of ventricular arrhythmias and mortality in patients with acute myocardial infarction (AMI). The aim of the present study was to evaluate whether different levels of serum potassium, within the normal range, are associated with worse outcomes. The present study comprised 1277 patients with AMI and normal-range admission potassium levels (3.5–5.2 mEq/L), who were enrolled and prospectively followed up in the Acute Coronary Syndrome Israeli Survey between 2010 and 2013. Patients were divided into 4 quartiles based on admission potassium levels; “normal-low” (K ≥ 3.5 and K ≤ 3.9), “normal-moderate” (K > 3.9 and K ≤ 4.18), “normal-high” (K > 4.18 and K ≤ 4.45), and “normal-very high” (K > 4.45 and K ≤ 5.2). We analyzed the association between admission serum potassium levels and 7 days in-hospital complication rates, and 30-day and 1-year all-cause mortality rates. Patients with “normal-very high” potassium displayed increased frequency of baseline clinical risk factors and experienced a higher rate of acute kidney injury during hospitalization compared with the “normal-low” group (7.7% vs 2.4%; P = 0.002). However, the rate of in-hospital ventricular arrhythmias was similar across the range of admission potassium levels (overall P = 0.26), Multivariate analysis showed that compared with “low-normal” potassium values, patients with “normal-very high” potassium levels experienced increased risk for 30-days (adjusted hazard ratio 2.88, 95% confidence interval 1.05–7.87, P = 0.039) and 1-year all-cause mortality (adjusted hazard ratio 1.98, 95% confidence interval 1.05–3.75, P = 0.034). In patients admitted with AMI, admission serum potassium levels of 4.45 to 5.2 mEq/L are not associated with in-hospital ventricular arrhythmias, but are associated with increased short and long-term mortality.

Abstract 18150: Ventricular Arrhythmia During Post Cardiac Arrest Care: Prognostic Importance and Influence of Pre-hospital Defibrillation - A TTM Substudy

Background: Ventricular arrhythmias (VA) are life threatening, even in patients admitted to an intensive care unit following out-of-hospital cardiac arrest (OHCA). Post cardiac arrest care includes hemodynamic stabilization and targeted temperature management (TTM) and while most patients are stabilized, VA may occur. We assessed the prognosis of OHCA patients with in-hospital VA and whether the number of pre-hospital defibrillations was predictive of in-hospital arrhythmic events. Method: We studied 934 (99%) comatose OHCA survivors from the TTM-trial (year: 2010-13) with available data on VA during the first 2 days of post cardiac arrest care and the number of pre-hospital defibrillation used to achieve return of spontaneous circulation (ROSC). The TTM trial showed no benefit of TTM at 33°C over 36°C in terms of mortality and neurological outcome. Results: The prevalence of VA was 16% and did not differ between the TTM groups (33°C= 82 (17%) vs. 36°C= 67 (15%), p=0.23). Patients with VA had similar 180-day survival rates (VA= 52% vs. no-VA= 53%, plog-rank= 0.63, Figure) and odds of unfavorable neurological outcome (OR=1.04 (0.73-1.48, p=0.83), compared to patients without VA. The number of pre-hospital defibrillations ranged from 0 to &gt;20 and a twofold increase was associated with significantly higher odds of in-hospital VA, both combined (OR= 1.39 (1.22-1.59, p&lt;0.0001), and separately as risk of ventricular tachycardia (OR= 1.39 (1.20-1.60, p&lt;0.0001) and fibrillation (OR= 1.54 (1.23-1.93 p&lt;0.001). This remained significant when adjusting for STEMI, initial rhythm, age, sex, bystander CPR, time to ROSC and admission lactate. Conclusion: Risk of VA is directly related to the number of pre-hospital defibrillations, which may be of value in predicting patients at risk of arrhythmia. VA occurring during post cardiac arrest care has no significant impact on prognosis, which supports continued active treatment in patients with recurrent VA after OHCA.

Short-term and long-term mortality associated with ventricular arrhythmia in patients hospitalized with acute coronary syndrome

Ventricular arrhythmia (VA) in the setting of acute coronary syndrome (ACS) carries an ominous prognosis; however, long-term prognosis associated with VA in ACS in the Middle East is unknown. Accordingly, we sought to assess the incidence, in-hospital outcomes, and 1-year mortality of in-hospital VA in patients with ACS. The Second Gulf Registry of Acute Coronary Events (Gulf RACE-2) is a multinational observational study of patients with ACS, which enrolled 7930 patients. Of these, 333 (4.2%) developed VA during hospitalization. Patients with VA were significantly older (mean age 58.3 vs. 56.8 years), and had a significantly higher rate of prior stroke/transient ischemic attack (7.5 vs. 4.2%), smoking (36.6 vs. 35.6%), congestive heart failure (11.0 vs. 6.5%), and peripheral artery disease (6.5 vs. 1.7%), compared with patients without VA. They had significantly less diabetes mellitus (35.4 vs. 40.3%), hypertension (43.2 vs. 47.9%), percutaneous coronary intervention (6.1 vs. 9.4%), and dyslipidemia (22.4 vs. 38.2%). The adjusted odds ratios for in-hospital, 30-day, and 1-year mortality in VA complicating all ACS were 25.8, 11.1, and 7.3; ST-elevation myocardial infarctions were 18.3, 11.7, and 6.3; and unstable angina and non-ST elevation myocardial infarctions were 47.4, 10.3, and 18.7, respectively (all P<0.001). In-hospital VA in patients with ACS with and without ST elevation was associated with significantly higher in-hospital, 30-day, and 1-year mortality. Noticeably higher long-term mortality among Middle Eastern patients with ACS having VA compared with other reports requires further study and warrants immediate attention.