23 research outputs found

    Recurrent ventricular arrhythmias and mortality in cardiac arrest survivors with a reversible cause with and without an implantable cardioverter defibrillator: A systematic review

    No full text
    Background: Sudden cardiac arrest survivors with a reversible cause are not eligible for implantable cardioverter defibrillator (ICD) implantation. This study aims to evaluate the risk of recurrent ventricular arrhythmia in sudden cardiac arrest survivors with a reversible cause and evaluate if ICD implantation increases survival. Methods: We conducted a systematic review to identify studies evaluating ICD implantation in sudden cardiac arrest survivors with a reversible cause. Outcomes were mortality and appropriate device therapy. Sudden cardiac arrest patients were divided into 4 subgroups: due to acute myocardial infarction; due to coronary artery spasm; due to takotsubo cardiomyopathy; and studies with various reversible causes of cardiac arrest. Results: 27 studies were included, evaluating 11,402 patients. A total of 2570 patients received an ICD. Studies evaluating coronary artery spasm and with various reversible causes showed a relatively high rate of appropriate device therapy (17% and 20%) and described an increased survival in ICD patients. Takotsubo cardiomyopathy was associated with a low mortality and none of the ICD patients received appropriate device therapy. Studies evaluating acute myocardial infarction survivors reported inconsistent results, with high numbers of appropriate device therapy (12–66%), but the mortality-rate of patients with and without an ICD varied. Conclusion: This study shows that the recurrence risk of ventricular arrhythmia varies between different reversible causes of sudden cardiac arrest and should not be evaluated as one entity. Cardiac arrest survivors with a reversible cause can be at risk of recurrent ventricular arrhythmia and selected patients may benefit from ICD implantation

    Снижение потерь при электродуговой сварке

    No full text
    BACKGROUND: The aims of this study were to determine the optimal tracer kinetic model for [(11)C]-meta-hydroxyephedrine ([(11)C]HED) and to evaluate the performance of several simplified methods. METHODS: Thirty patients underwent dynamic 60-min [(11)C]HED scans with online arterial blood sampling. Single-tissue and both reversible and irreversible two-tissue models were fitted to the data using the metabolite-corrected arterial input function. For each model, reliable fits were defined as those yielding outcome parameters with a coefficient of variation (CoV) <25%. The optimal model was determined using Akaike and Schwarz criteria and the F-test, together with the number of reliable fits. Simulations were performed to study accuracy and precision of each model. Finally, quantitative results obtained using a population-averaged metabolite correction were evaluated, and simplified retention index (RI) and standardized uptake value (SUV) results were compared with quantitative volume of distribution (V T) data. RESULTS: The reversible two-tissue model was preferred in 75.8% of all segments, based on the Akaike information criterion. However, V T derived using the single-tissue model correlated highly with that of the two-tissue model (r (2) = 0.94, intraclass correlation coefficient (ICC) = 0.96) and showed higher precision (CoV of 24.6% and 89.2% for single- and two-tissue models, respectively, at 20% noise). In addition, the single-tissue model yielded reliable fits in 94.6% of all segments as compared with 77.1% for the reversible two-tissue model. A population-averaged metabolite correction could not be used in approximately 20% of the patients because of large biases in V T. RI and SUV can provide misleading results because of non-linear relationships with V T. CONCLUSIONS: Although the reversible two-tissue model provided the best fits, the single-tissue model was more robust and results obtained were similar. Therefore, the single-tissue model was preferred. RI showed a non-linear correlation with V T, and therefore, care has to be taken when using RI as a quantitative measure

    Quantification of [(11)C]-meta-hydroxyephedrine uptake in human myocardium

    No full text
    BACKGROUND: The aims of this study were to determine the optimal tracer kinetic model for [(11)C]-meta-hydroxyephedrine ([(11)C]HED) and to evaluate the performance of several simplified methods. METHODS: Thirty patients underwent dynamic 60-min [(11)C]HED scans with online arterial blood sampling. Single-tissue and both reversible and irreversible two-tissue models were fitted to the data using the metabolite-corrected arterial input function. For each model, reliable fits were defined as those yielding outcome parameters with a coefficient of variation (CoV) <25%. The optimal model was determined using Akaike and Schwarz criteria and the F-test, together with the number of reliable fits. Simulations were performed to study accuracy and precision of each model. Finally, quantitative results obtained using a population-averaged metabolite correction were evaluated, and simplified retention index (RI) and standardized uptake value (SUV) results were compared with quantitative volume of distribution (V T) data. RESULTS: The reversible two-tissue model was preferred in 75.8% of all segments, based on the Akaike information criterion. However, V T derived using the single-tissue model correlated highly with that of the two-tissue model (r (2) = 0.94, intraclass correlation coefficient (ICC) = 0.96) and showed higher precision (CoV of 24.6% and 89.2% for single- and two-tissue models, respectively, at 20% noise). In addition, the single-tissue model yielded reliable fits in 94.6% of all segments as compared with 77.1% for the reversible two-tissue model. A population-averaged metabolite correction could not be used in approximately 20% of the patients because of large biases in V T. RI and SUV can provide misleading results because of non-linear relationships with V T. CONCLUSIONS: Although the reversible two-tissue model provided the best fits, the single-tissue model was more robust and results obtained were similar. Therefore, the single-tissue model was preferred. RI showed a non-linear correlation with V T, and therefore, care has to be taken when using RI as a quantitative measure

    Usefulness of Left Atrial Emptying Fraction to Predict Ventricular Arrhythmias in Patients With Implantable Cardioverter Defibrillators

    No full text
    Impaired left atrial emptying fraction (LAEF) is an important predictor of mortality in patients with heart failure. As it may reflect increased LV wall stress, it might predict ventricular arrhythmia (VA) specifically. This study evaluated the predictive value of LAEF assessed with cardiovascular magnetic resonance (CMR) imaging with respect to appropriate device therapy (ADT) for VA and compared its role with CMR assessed scar size and other risk factors. In total, 229 patients (68% male, 63 ± 10 years, 61% ischemic cardiomyopathy) with LV ejection fraction ≤35% who underwent CMR and implantable cardioverter defibrillator (ICD) implantation for primary prevention in 2005 to 2012 were included. CMR was used to quantify LV volumes and function. LV scar size was quantified when late gadolinium enhancement was available (n = 166). Maximum and minimum left atrial volumes and LAEF were calculated using the biplane area-length method. The occurrence of ADT and mortality was assessed during a median follow-up of 3.9 years. Sixty-two patients (27%) received ADT. Univariable Cox analysis showed that male gender, creatinine level, minimum left atrial volume, LAEF, and total scar size were significant predictors of ADT. In multivariable Cox analysis, LAEF (hazard ratio 0.75 per 10%, p median and scar size median experienced 40% ADT at 5 years (log-rank p = 0.01). In conclusion, LAEF independently predicts ADT in patients with primary prevention ICDs. Combined assessment of LAEF and scar size identifies a group with low risk of ADT. Therefore, LAEF assessment could assist in risk stratification for VA to select patients with the highest benefit from ICD implantation

    The link between cardiac status and depression and anxiety in implantable cardioverter defibrillator patients: Design and first results of the PSYCHE-ICD study

    No full text
    Objective: Depression and anxiety in patients with an implantable cardioverter-defibrillator (ICD) are associated with adverse outcomes. This study describes the design of the PSYCHE-ICD study and evaluates the correlation between cardiac status and depression and anxiety in ICD patients. Methods: We included 178 patients. Prior to implantation, patients completed validated psychological questionnaires for depression, anxiety and personality traits. Cardiac status was evaluated by means of left ventricular ejection fraction assessment (LVEF), New York Heart Association (NYHA) functional class, 6-minute walk test (6MWT), and 24-h Holter monitoring for heart rate variability (HRV). A cross-sectional analysis was performed. Follow-up with annual study visits, including repeated full cardiac evaluation, will continue 36 months after ICD implantation. Results: Depressive symptoms were present in 62 (35%) and anxiety in 56 (32%) patients. Values of depression and anxiety significantly increased with higher NYHA class (P < 0.001). Depression symptoms were correlated with a reduced 6MWT (411 ± 128 vs. 488 ± 89, P < 0.001), higher heart rate (74 ± 13 vs. 70 ± 13, P = 0.02), higher thyroid stimulation hormone levels (1.8 [1.3–2.8] vs 1.5 [1.0–2.2], P = 0.03) and multiple HRV parameters. Anxiety symptoms were correlated with higher NYHA class and a reduced 6MWT (433 ± 112 vs 477 ± 102, P = 0.02). Conclusion: A substantial part of patients receiving an ICD have symptoms of depression and anxiety at time of ICD implantation. Depression and anxiety were correlated with multiple cardiac parameters, suggesting a possible biological links between psychological distress and cardiac disease in ICD patients

    Sex-specific differences in outcome and risk stratification of ventricular arrhythmias in implantable cardioverter defibrillator patients

    No full text
    Aims: Risk stratification models of sudden cardiac death (SCD) are based on the assumption that risk factors of SCD affect risk to a similar extent in both sexes. The aim of the study is to evaluate differences in clinical outcomes between sexes and evaluate whether risk factors associated with appropriate device therapy (ADT) differ between men and women. Methods and results: We performed a cohort study of implantable cardioverter defibrillator (ICD) patients referred for primary or secondary prevention of SCD between 2009 and 2018. Multivariable Cox regression models for prediction of ADT were constructed for men and women separately. Of 2300 included patients, 571 (25%) were women. Median follow-up was 4.6 (inter-quartile range: 4.4–4.9) years. Time to ADT was shorter for men compared with women [hazard ratio (HR) 1.71, P < 0.001], as was time to mortality (HR 1.37, P = 0.003). In women, only secondary prevention ICD therapy (HR 1.82, P < 0.01) was associated with ADT, whereas higher age (HR 1.20, P < 0.001), absence of left bundle branch block (HR 0.72, P = 0.01), and secondary prevention therapy (HR 1.80, P < 0.001) were independently associated with ADT in men. None of the observed parameters showed a distinctive sex-specific pattern in ADT. Conclusions: Male ICD patients were at higher risk of ADT and death compared with female ICD patients, irrespective of an ischaemic or non-ischaemic underlying cardiomyopathy. Our study highlights the importance to stratify outcomes of ICD trials by sex, as study results differ between men and women. However, none of the available clinical parameters showed a clear sex-specific relation to ventricular arrhythmias. As a consequence, sex-specific risk stratification models of SCD using commonly available clinical parameters could not be derived
    corecore