Dávid Becker

Prediction model to estimate presence of coronary artery disease: Retrospective pooled analysis of existing cohorts

Objectives To develop prediction models that better estimate the pretest probability of coronary artery disease in low prevalence populations. Design Retrospective pooled analysis of individual patient data. Setting 18 hospitals in Europe and the United States. Participants Patients with stable chest pain without evidence for previous coronary artery disease, if they were referred for computed tomography (CT) based coronary angiography or catheter based coronary angiography (indicated as low and high prevalence settings, respectively). Main outcome measures Obstructive coronary artery disease (≥50% diameter stenosis in at least one vessel found on catheter based coronary angiography). Multiple imputation accounted for missing predictors and outcomes, exploiting strong correlation between the two angiography procedures. Predictive models included a basic model (age, sex, symptoms, and setting), clinical model (basic model factors and diabetes, hypertension, dyslipidaemia, and smoking), and extended model (clinical model factors and use of the CT based coronary calcium score). We assessed discrimination (c statistic), calibration, and continuous net reclassification improvement by cross validation for the four largest low prevalence datasets separately and the smaller remaining low prevalence datasets combined. Results We included 5677 patients (3283 men, 2394 women), of whom 1634 had obstructive coronary artery disease found on catheter based coronary angiography. All potential predictors were significantly associated with the presence of disease in univariable and multivariable analyses. The clinical model improved the prediction, compared with the basic model (cross validated c statistic improvement from 0.77 to 0.79, net reclassification improvement 35%); the coronary calcium score in the extended model was a major predictor (0.79 to 0.88, 102%). Calibration for low prevalence datasets was satisfactory. Conclusions Updated prediction models including age, sex, symptoms, and cardiovascular risk factors allow for accurate estimation of the pretest probability of coronary artery disease in low prevalence populations. Addition of coronary calcium scores to the prediction models improves the estimates.

Stabilization of the coronary sinus electrode position with coronary stent implantation to prevent and treat dislocation.

Introduction: Coronary sinus (CS) leads used for cardiac resynchronization have undergone development in the last years. However, dislocation rate remained high (5–9%). The aim of this study was to investigate the effectiveness and safety of stent implantation in a CS side vein to stabilize the left ventricular lead position after postoperative or intraoperative dislocation of the electrode.

Effect of cardiac resynchronization therapy with implantable cardioverter defibrillator versus cardiac resynchronization therapy with pacemaker on mortality in heart failure patients : results of a high-volume, single-centre experience

There are limited and contradictory data on the effects of CRT with implantable cardioverter defibrillator (CRT‐D) on mortality as compared with CRT with pacemaker (CRT‐P).

Role of Right Ventricular Global Longitudinal Strain in Predicting Early and Long-Term Mortality in Cardiac Resynchronization Therapy Patients

Background Right ventricular (RV) dysfunction has been associated with poor prognosis in chronic heart failure (HF). However, less data is available about the role of RV dysfunction in patients with cardiac resynchronization therapy (CRT). We aimed to investigate if RV dysfunction would predict outcome in CRT. Design We enrolled prospectively ninety-three consecutive HF patients in this single center observational study. All patients underwent clinical evaluation and echocardiography before CRT and 6 months after implantation. We assessed RV geometry and function by using speckle tracking imaging and calculated strain parameters. We performed multivariable Cox regression models to test mortality at 6 months and at 24 months. Results RV dysfunction, characterized by decreased RVGLS (RV global longitudinal strain) [10.2 (7.0–12.8) vs. 19.5 (15.0–23.9) %, p<0.0001] and RVFWS (RV free wall strain) [15.6 (10.0–19.3) vs. 17.4 (10.5–22.2) %, p = 0.04], improved 6 months after CRT implantation. Increasing baseline RVGLS and RVFWS predicted survival independent of other parameters at 6 months [hazard ratio (HR) = 0.37 (0.15–0.90), p = 0.02 and HR = 0.42 (0.19–0.89), p = 0.02; per 1 standard deviation increase, respectively]. RVGLS proved to be a significant independent predictor of mortality at 24 months [HR = 0.53 (0.32–0.86), p = 0.01], and RVFWS showed a strong tendency [HR = 0.64 (0.40–1.00), p = 0.05]. The 24-month survival was significantly impaired in patients with RVGLS below 10.04% before CRT implantation [area under the curve = 0.72 (0.60–0.84), p = 0.002, log-rank p = 0.0008; HR = 5.23 (1.76–15.48), p = 0.003]. Conclusions Our findings indicate that baseline RV dysfunction is associated with poor short-term and long-term prognosis after CRT implantation.

Clinical predictors of mortality following rotational atherectomy and stent implantation in high‐risk patients: A single center experience

Our aim was to assess the procedural success and determine the clinical predictors of postprocedure mortality, following rotational atherectomy (RA) and stenting in high‐risk patients.

The ratio of the neutrophil leucocytes to the lymphocytes predicts the outcome after cardiac resynchronization therapy.

Abstract Aims The low lymphocyte counts and high neutrophil leucocyte fractions have been associated with poor prognosis in chronic heart failure. We hypothesized that the baseline ratio of the neutrophil leucocytes to the lymphocytes (NL ratio) would predict the outcome of chronic heart failure patients undergoing cardiac resynchronization therapy (CRT). Methods and results The qualitative blood counts and the serum levels of N-terminal of the prohormone brain natriuretic peptide (NT-proBNP) of 122 chronic heart failure patients and 122 healthy controls were analysed prospectively in this observational study. The 2-year mortality was considered as primary endpoint and the 6-month reverse remodelling (≥15% decrease in the end-systolic volume) as secondary endpoint. Multivariable regression analyses were applied and net reclassification improvement (NRI) and integrated discrimination improvement (IDI) were calculated. The NL ratio was elevated in chronic heart failure patients when compared with the healthy controls [2.93 (2.12–4.05) vs. 2.21 (1.64–2.81), P < 0.0001]. The baseline NL ratio exceeding 2.95 predicted the lack of the 6-month reverse remodelling [n = 63, odds ratio = 0.38 (0.17–0.85), P = 0.01; NRI = 0.49 (0.14–0.83), P = 0.005; IDI = 0.04 (0.00–0.07), P = 0.02] and the 2-year mortality [n = 29, hazard ratio = 2.44 (1.04–5.71), P = 0.03; NRI = 0.63 (0.24–1.01), P = 0.001; IDI = 0.04 (0.00–0.08), P = 0.02] independently of the NT-proBNP levels or other factors. Conclusion The NL ratio is elevated in chronic heart failure and predicts outcome after CRT. According to the reclassification analysis, 4% of the patients would have been better categorized in the prediction models by combining the NT-proBNP with the NL ratio. Thus, a single blood count measurement could facilitate the optimal patient selection for the CRT.

Ultrastructure and composition of thrombi in coronary and peripheral artery disease: Correlations with clinical and laboratory findings

INTRODUCTION Fibrin structure and cellular composition of thrombi profoundly affect the clinical outcomes in ischemic coronary and peripheral artery disease. Our study addressed the interrelations of structural features of thrombi and routinely measured laboratory parameters. MATERIALS AND METHODS Thrombi removed by thromboaspiration following acute myocardial infarction (n=101) or thrombendarterectomy of peripheral arteries (n=50) were processed by scanning electron microscopy and immunostaining for fibrin and platelet antigen GPIIb/IIIa to determine fibrin fibre diameter and relative occupancy by fibrin and cells. Correlations between the structural characteristics and selected clinical parameters (age, sex, vascular localization, blood cell counts, ECG findings, antiplatelet medication, accompanying diseases, smoking) were assessed. RESULTS We observed significant differences in mean fibre diameter (122 vs. 135 nm), fibrin content (70.5% vs. 83.9%), fluorescent fibrin/platelet coverage ratio (0.18 vs. 1.06) between coronary and peripheral thrombi. Coronary thrombi from smokers contained more fibrin than non-smokers (78.1% vs. 62.2% mean occupancy). In the initial 24 h, fibrin content of coronary thrombi decreased with time, whereas in peripheral thrombi platelet content increased in the first 7 days. In coronaries, higher platelet content and smaller vessel diameter were associated with thinner fibrin fibres, whereas hematocrit higher than 0.35 correlated with larger intrathrombotic platelet occupancy. Smoking and dyslipidaemia strengthened the dependence of clot platelet content on systemic platelet count (the adjusted determination coefficient increased from 0.33 to 0.43 and 0.65, respectively). CONCLUSION Easily accessible clinical parameters could be identified as significant determinants of ultrastructure and composition of coronary and peripheral thrombi.

Complement Activation and its Prognostic role in Post‐cardiac Arrest Patients

Cardiac arrest causes generalized ischaemia/hypoxia, and subsequent resuscitation inflicts reperfusion injury, the pathology of which is not fully understood. Moreover, predicting the prognosis of comatose, post‐cardiac arrest patients is a complex clinical challenge. We hypothesized that the extent of complement activation might be a reliable predictor of mortality in this population. Forty‐six comatose cardiac arrest patients were enrolled into our prospective cohort study, conducted in a tertiary care university clinic. All subjects were cooled to 32–34 °C body temperature for 24 h and then allowed to rewarm to normothermia. All patients underwent diagnostic coronary angiography. On admission, at 6 and 24 h, blood samples were taken from the arterial catheter. In these, complement products (C3a, C3, C4d, C4, SC5b9 and Bb) were measured by ELISA in blood samples. Patients were followed up for 30 days; 22 patients (47.8%) died by the end of this period. We observed that complement activation (determined as the C3a to C3 ratio) was higher in non‐survivors than in survivors at each time point. In the multivariate Cox regression analysis, the C3a/C3 ratio determined 24 h after the initiation of therapeutic hypothermia predicted 30‐day mortality regardless of age, sex and the APACHE II score. Complement activation occurs in post‐cardiac arrest patients, and its extent correlates with 30‐day survival. The C3a/C3 ratio might prove useful for estimating the prognosis of comatose post‐cardiac arrest patients.

Rotational atherectomy of undilatable coronary stents: Stentablation, a clinical perspective and recommendation

AIMS Our aim was to examine procedural viability and midterm outcomes following the use of rotational atherectomy (RA) on malapposed, crippled, otherwise non-salvageable metallic stents (i.e., stentablation [SA]), and convey important procedural pointers for practitioners encountering such situations. METHODS AND RESULTS Data on twelve SA subjects were analysed. The primary endpoint was procedural success: effective ablation of the malapposed stent and successful implantation of a new device. Major adverse cardiac events (MACE) and all-cause death at six months following the index procedure were examined as a secondary endpoint. All twelve patients underwent successful SA and novel stent implantation, with sufficient salvage of coronary anatomy (residual stenosis <30%). At six-month follow-up, however, MACE amounted to 50% and all-cause mortality to 25% in the inspected subjects. CONCLUSIONS We found that, although feasible as an acute salvage option, SA distinctively increases post-procedural midterm MACE and mortality rates. This places emphasis on the importance of avoiding eventual SA situations, underlining the importance of ample lesion preparation prior to stent implantation.

Successful management and long term outcome of an accidental subclavian artery injury with a 9 french dilator during pacemaker implantation with collagen-based closure device

Subclavian artery puncture and dilation with 9 Fr dilator during pacemaker implantation is a rare complication. We present a case, where this complication occurred and the injury was sealed with collagen-based closure device without any complications. Long term follow-up and the control angio-CT revealed no further late vascular complications. Therefore, use of a collagen based closure device for treating accidental iatrogenic subclavian artery injury can be a simple, successful alternative therapy when surgical direct vascular repair is not possible or not available.