Rapid Improvements in Physical Activity and Sedentary Behavior in Patients With Acute Myocardial Infarction Immediately Following Hospital Discharge

Background Little is known about changes in physical activity (PA) and sedentary behavior (SB) patterns in the acute phase of a myocardial infarction (MI). We objectively assessed PA and SB during hospitalization and the first week after discharge. Methods and Results Consecutively admitted patients hospitalized with an MI were approached to participate in this prospective cohort study. SB, light-intensity PA, and moderate-vigorous intensity PA were objectively assessed for 24 h/d during hospitalization and up to 7 days after discharge in 165 patients. Changes in PA and SB from the hospital to home phase were evaluated using mixed-model analyses, and outcomes were stratified for predefined subgroups based on patient characteristics. Patients (78% men) were aged 65±10 years and diagnosed with ST-segment-elevation MI (50%) or non-ST-segment-elevation MI (50%). Sedentary time was high during hospitalization (12.6 [95% CI, 11.8-13.7] h/d) but substantially decreased following transition to the home environment (-1.8 [95% CI, -2.4 to -1.3] h/d). Furthermore, the number of prolonged sedentary bouts (≥60 minutes) decreased between hospital and home (-1.6 [95% CI, -2.0 to -1.2] bouts/day). Light-intensity PA (1.1 [95% CI, 0.8-1.6] h/d) and moderate-vigorous intensity PA (0.2 [95% CI, 0.1-0.3] h/d) were low during hospitalization but significantly increased following transition to the home environment (light-intensity PA: 1.8 [95% CI, 1.4-2.3] h/d; moderate-vigorous intensity PA: 0.4 [95% CI, 0.3-0.5] h/d; both P<0.001). Improvements in PA and SB were similar across groups, except for patients who underwent coronary artery bypass grafting and who did not improve their PA patterns after discharge. Conclusions Patients with MI demonstrate high levels of SB and low PA volumes during hospitalization, which immediately improved following discharge at the patient's home environment. Registration URL: trialsearch.who.int/; Unique identifier: NTR7646.

Acute rule-out of non-ST-segment elevation acute coronary syndrome in the (pre)hospital setting by HEART score assessment and a single point-of-care troponin: rationale and design of the ARTICA randomised trial

INTRODUCTION

Because of the lack of prehospital protocols to rule out a non-ST-segment elevation acute coronary syndrome (NSTE-ACS), patients with chest pain are often transferred to the emergency department (ED) for thorough evaluation. However, in low-risk patients, an ACS is rarely found, resulting in unnecessary healthcare consumption. Using the HEART (History, ECG, Age, Risk factors and Troponin) score, low-risk patients are easily identified. When a point-of-care (POC) troponin measurement is included in the HEART score, an ACS can adequately be ruled out in low-risk patients in the prehospital setting. However, it remains unclear whether a prehospital rule-out strategy using the HEART score and a POC troponin measurement in patients with suspected NSTE-ACS is cost-effective.

METHODS AND ANALYSIS

The ARTICA trial is a randomised trial in which the primary objective is to investigate the cost-effectiveness after 30 days of an early rule-out strategy for low-risk patients suspected of a NSTE-ACS, using a modified HEART score including a POC troponin T measurement. Patients are included by ambulance paramedics and 1:1 randomised for (1) presentation at the ED (control group) or (2) POC troponin T measurement (intervention group) and transfer of the care to the general practitioner in case of a low troponin T value. In total, 866 patients will be included. Follow-up will be performed after 30 days, 6 months and 12 months.

ETHICS AND DISSEMINATION

This trial has been accepted by the Medical Research Ethics Committee region Arnhem-Nijmegen. The results of this trial will be disseminated in one main paper and in additional papers with subgroup analyses.

TRIAL REGISTRATION NUMBER

Netherlands Trial Register (NL7148).

Temporal Pattern of Growth Differentiation Factor-15 Protein After Acute Coronary Syndrome (From the BIOMArCS Study)

Growth differentiation factor-15 (GDF-15) has appeared as a promising biomarker with strong predictive abilities in acute coronary syndrome (ACS). However, studies are solely based on single measurements in the acute phase of an ACS event. The way GDF-15 patterns in post-ACS patients behave on the long term is largely unknown. We conducted a nested case-control study within our multicenter, prospective, observational biomarker study (BIOMArCS) of 844 ACS patients. Following an index ACS event, high-frequency blood sampling was performed during 1-year of follow-up. GDF-15 was determined batchwise by electrochemiluminescence immunoassays in 37 cases with a recurrent event during 1-year follow-up, and in 74 event-free controls. Cases and controls had a mean ± standard deviation age of 66.9 ± 11.3 years and 81% were men. From 30 days onwards, patients showed stable levels, which were on average 333 (95% confidence interval 68 to 647) pg/mL higher in cases than controls (1704 vs 1371 pg/mL; p value 0.013). Additionally, in the post 30-day period, GDF-15 showed low within-individual variability in both cases and controls. In conclusion, post-ACS patients experiencing a recurrent event had stable and systematically higher GDF-15 levels during 30-day to 1-year follow-up than their event-free counterparts with otherwise similar clinical characteristics. Thus, postdischarge blood sampling might be used throughout the course of 1 year to improve prognostication, whereas, in view of the low within-individual variation, the number of repeated sampling moments might be limited.

Cohort profile of BIOMArCS: the BIOMarker study to identify the Acute risk of a Coronary Syndrome-a prospective multicentre biomarker study conducted in the Netherlands

PURPOSE

Progression of stable coronary artery disease (CAD) towards acute coronary syndrome (ACS) is a dynamic and heterogeneous process with many intertwined constituents, in which a plaque destabilising sequence could lead to ACS within short time frames. Current CAD risk assessment models, however, are not designed to identify increased vulnerability for the occurrence of coronary events within a precise, short time frame at the individual patient level. The BIOMarker study to identify the Acute risk of a Coronary Syndrome (BIOMArCS) was designed to evaluate whether repeated measurements of multiple biomarkers can predict such 'vulnerable periods'.

PARTICIPANTS

BIOMArCS is a multicentre, prospective, observational study of 844 patients presenting with ACS, either with or without ST-elevation and at least one additional cardiovascular risk factor.

METHODS AND ANALYSIS

We hypothesised that patterns of circulating biomarkers that reflect the various pathophysiological components of CAD, such as distorted lipid metabolism, vascular inflammation, endothelial dysfunction, increased thrombogenicity and ischaemia, diverge in the days to weeks before a coronary event. Divergent biomarker patterns, identified by serial biomarker measurements during 1-year follow-up might then indicate 'vulnerable periods' during which patients with CAD are at high short-term risk of developing an ACS. Venepuncture was performed every fortnight during the first half-year and monthly thereafter. As prespecified, patient enrolment was terminated after the primary end point of cardiovascular death or hospital admission for non-fatal ACS had occurred in 50 patients. A case-cohort design will explore differences in temporal patterns of circulating biomarkers prior to the repeat ACS.

FUTURE PLANS AND DISSEMINATION

Follow-up and event adjudication have been completed. Prespecified biomarker analyses are currently being performed and dissemination through peer-reviewed publications and conference presentations is expected from the third quarter of 2016. Should identification of a 'vulnerable period' prove to be feasible, then future research could focus on event reduction through pharmacological or mechanical intervention during such periods of high risk for ACS.

TRIAL REGISTRATION NUMBER

NTR1698 and NTR1106.

Influence of selection bias on the test decision. A simulation study

BACKGROUND

Selection bias arises in clinical trials by reason of selective assignment of patients to treatment groups. Even in randomized clinical trials with allocation concealment this phenomenon can occur if future assignments can be predicted due to knowledge of former allocations.

OBJECTIVES

Considering unmasked randomized clinical trials with allocation concealment the impact of selection bias on type I error rate under permuted block randomization is investigated. We aimed to extend the existing research into this topic by including practical assumptions concerning misclassification of patient characteristics to get an estimate of type I error close to clinical routine. To establish an upper bound for the type I error rate different biasing strategies of the investigator are compared first. In addition, the aspect of patient availability is considered.

METHODS

To evaluate the influence of selection bias on type I error rate under several practical situations, different block sizes, selection effects, biasing strategies and success rates of patient classification were simulated using SAS.

RESULTS

Type I error rate exceeds 5 percent significance level; it reaches values up to 21 percent. More cautious biasing strategies and misclassification of patient characteristics may diminish but cannot eliminate selection bias. The number of screened patients is about three times larger than the needed number for the trial.

CONCLUSIONS

Even in unmasked randomized clinical trials using permuted block randomization with allocation concealment the influence of selection bias must not be disregarded evaluating the test decision. It should be incorporated when designing and reporting a clinical trial.

Recombinant hirudin for cardiopulmonary bypass anticoagulation: a randomized, prospective, and heparin-controlled pilot study

BACKGROUND

Lepirudin, a recombinant hirudin, is a direct acting thrombin inhibitor that has been used as a heparin alternative in patients with heparin-induced thrombocytopenia requiring on-pump cardiac surgery. To evaluate the efficacy, safety, and clinical utility of lepirudin as a cardiopulmonary bypass (CPB) anticoagulant, we compared lepirudin with heparin in a routine CPB setting.

METHODS

Twenty patients were randomly assigned to receive lepirudin (0.25 mg/kg b. w. bolus and 0.2 mg/kg b. w. added to the CPB priming) or heparin (400 U/kg b. w. bolus) with protamine reversal. Lepirudin and heparin anticoagulation during CPB was monitored using the ecarin clotting time or ACT, respectively and additional lepirudin (5 mg) or heparin (5000 U) boluses were administered.

RESULTS

The CPB circuit was performed in both groups without thromboembolic complications. Median blood loss during the first 36 hours was statistically higher ( P = 0.007) in the lepirudin group (1.226 +/- 316 ml) compared to the heparin group (869 +/- 189 ml). One patient of the lepirudin group developed pulmonary embolism 24 hours after surgery. This patient was tested homozygous for the FV-Leiden mutation.

CONCLUSION

Lepirudin provides effective CPB anticoagulation but induces a higher postoperative blood loss than heparin. Lepirudin should be restricted to patients undergoing CPB who cannot be exposed to heparin.

Troponin I release at rest and after exercise in patients with hypertrophic cardiomyopathy and the effect of betablockade

PURPOSE OF THE WORK

In patients with hypertrophic cardiomyopathy ischemia may occur due to massive heart weight, myocyte disarray or small vessel disease. We detected elevated troponin levels in some of these patients and hypothesized that troponin release would rise after exercise and diminish after betablockade.

METHODS AND RESULTS

In 5 of 7 young patients (6 males) with hypertrophic cardiomyopathy and no overt coronary artery disease we found elevated troponin levels after physical exercise; the peak was between 6 and 9 hours and levels returned to pre-exercise values within 24 hours. Troponin release was consistently diminished after use of a betablocker.

CONCLUSIONS

Increased troponin release may be present in patients with hypertrophic cardiomyopathy and is temporarily enhanced by exercise and diminishes with betablockade.

A phase II study of low-dose prolonged infusional gemcitabine combined with oral treosulfan in patients with platinum- and taxane-resistant ovarian cancer or other Mullerian tract carcinomas

15004

The prognosis of patients (pts) with epthelial ovarian cancer (EOC) and other Mullerian tract carcinomas such as papillary-serous peritoneal carcinoma (PSPC), fallopian tube cancer (FTC), and uterine papillary-serous carcinoma (UPSC) resistant to both platinum and taxanes is particularly poor. Recently, we have reported preliminary results of modified GeT - gemcitabine (dFdC) and treosulfan (TREO) (Kurbacher et al, Proc ASCO 2005). Now, mature results of this phase II trial are available. A total of 35 patients (pts) were included (EOC, 29; FTC, 4; PSPC, 1; UPSC, 1). Patients had failed a median of 2 prior chemotherapies (1, n = 10; 2, n = 11; 3, n = 7; 4, n = 3; 5, n = 3; 7, n = 1) including platinum and paclitaxel in all, anthracyclines in 16, dFdC in either 6, and topotecan in 5 pts. GeT was administered at a q2w schedule with dFdC at 450 mg/m2 (3 h infusion), day 1, and oral TREO at 1,000 mg/m2/d, day 1–4. A total of 192 cycles were given with a median of 6 (range: 2–10). All pts had measurable or evaluable disease according to RECIST and Rustin criteria, repectively. All treatments were evaluable for both toxicity and response. Myelosuppression was frequent but exceeded NCI-CTC grade 2 in only 17/192 cycles (9%). G 3–4 neutropenia was observed during 5/192 cycles (3%), G 3–4 thrombocytopenia did not occur. Interval prolongation due to febrile urinary tract infection or subileus was necessary in two pts. In another patient, treatment was terminated due to non-fatal pulmonary embolism. Other toxicities did not exceed NCI-CTC grade 2 nor did any other patient require hospitalization due to therapy-related complications. A total of 11 CR, 7 PR, 9 SD, and 8 PD were recorded accounting for an objective response rate of 51% with 27 pts (77%) benefiting from GeT. The median progression-free survival was 27 weeks. Until now, 15 pts are still alive, the median overall survival is 76.5 weeks. Regarding the intensive pre-treatment of the pts, the modified GeT treatment was easy to tolerate and produced a promising clinical efficacy in EOC and other Mullerian tract carcinomas resistant to both platinum and taxanes. Large-scaled clinical trials are now warrented to confirm these encouraging results.

No significant financial relationships to disclose.

Neoadjuvant, biweekly, dose-dense chemotherapy with epirubicin (E) and cyclophosphamide (C) followed by docetaxel (T) in primary breast cancer (BC)

10656

Background: Primary chemotherapy is established in the treatment of local advanced BC. Two important advances are the chance to detect the clinical responders during the chemotherapy and an increasing rate of breast conserving surgery (BCS). According to the promissing results of dose-dense chemotherapy schedules in the adjuvant setting we tested the benefit of this approach in a primary chemotherapy protocol. Methods: This clinical trial (01/2003–11/2005) enrolled 93 females with advanced (cT2-cT4), non metastatic BC. The pts received four courses of E (90 mg/m2) and C (600 mg/m2) q2w, followed by four courses of T (100/75 mg/m2) q2w. The severe hand-foot-skin reaction NCI-CTG grade 3 during the T courses of the first pts (G1: n = 19) lead to a dose reduction of T to 75 mg/m2 for the following pts (G2: n = 73). During the first four cycles Pegfilgrastim was applied to prevent neutropenic complications. After every two cycles the actual tumor size was measured by clinical and sonographical examination. The clinical and pathological response, the toxicity and the rate of BCS were evaluated. Results: Pathological complete remission (pCR) of the invasive tumors was observed in 7/19 pts (G1) and 17/73 (G2), pathological partial remission (pPR) in 7/19 pts (G1) and 28/73 (G2), minimal response (pMR) in 3/19 pts (G1) and 14/73 (G2), a stable disease in 2/19 pts (G1) and 11/73 (G2). Two pts in group two showed a progressive disease (pPD). Three pts developed neutropenic fever and stopped the chemotherapy after the 5th and 6th cycle, respectively. One patient died after the 8th cycle in neutropenic sepsis. During this trial the main side effect of T was a hand-foot-skin reaction. Conclusions: This neoadjuvant dose-dense chemotherapy is a potent schedule for the treatment of primary BC. Using T with 75 mg/m2 instead of 100 g/m2 is generally better tolerated. The first group of pts treated with T 100 mg/m2 exhibited a higher frequency of pCR (36.8%) compared to the pts treated with 75 mg/m2 (pCR 23.3%), (p = 0.23). But the increased rate of severe side effects lead to an early dose reduction to 75 mg/m2 in this clinical trial.These first promissing results will be improved in an enlarged number of pts.

No significant financial relationships to disclose.

The expression of prion protein (PrP(C)) in the megakaryocyte lineage

BACKGROUND

Cellular prion protein (PrP(C)) is a naturally occurring protein in normal individuals which adopts an abnormal conformation, termed scrapie prion protein (PrP(Sc)) that is associated with disease. There is great concern that clinically asymptomatic variant Creutzfeldt-Jacob disease (vCJD) may transmit PrP(Sc) in blood transfusion products. PrP(C) is widely expressed and has been found in human blood. The majority of cellular borne PrP(C) is associated with platelets (84%). Although PrP(C) mRNA has been demonstrated in platelets, the quantity is unknown and may not reflect the total PrP(C) present.

OBJECTIVE

To investigate the expression of PrP(C) in the megakaryocyte lineage.

METHODS

The expression of PrP(C) was studied in CD34+ cells, cultured megakaryocytes and platelets using electron microscopy, flow cytometry, semi-quantitative RT-PCR and immunofluorescence confocal microscopy.

RESULTS AND CONCLUSIONS

The expression of PrP(C) appeared to increase with differentiation and polyploidization in the megakaryocyte lineage. PrP(C) was located within platelet alpha-granules and its source is likely to be from megakaryocyte precursors. If PrP(Sc) has a similar distribution, these results have implications for the selection of blood donors and preparation of cell-depleted blood products.

Identification of CD146 as a component of the endothelial junction involved in the control of cell-cell cohesion

CD146 is a cell-surface molecule belonging to the immunoglobulin superfamily and expressed in all types of human endothelial cells. Confocal and electron microscopic analysis of confluent human umbilical vein endothelial cells (HUVECs) were used to demonstrate that CD146 is a component of the endothelial junction. Double immunolabeling with vascular endothelial cadherin showed that CD146 is localized outside the adherens junction. Moreover, CD146 expression is not restricted to the junction, since part of the labeling was detectable at the apical side of the HUVECs. Interestingly, cell-surface expression of CD146 increased when HUVECs reached confluence. In addition, the paracellular permeability of CD146-transfected fibroblast cells was decreased compared with that of control cells. Finally, CD146 colocalized with actin, was partly resistant to Triton X-100 extraction, and had its expression altered by actin-disrupting agents, indicating that CD146 is associated with the actin cytoskeleton. These results show the regulated expression of CD146 at areas of cell-cell junction and strongly suggest involvement of CD146 as a mediator of cell-cell interaction.

Compared effects of Mpl ligand and other cytokines on human MK differentiation

The discovery of the Mpl ligand (Mpl-L), also called thrombopoietin (TPO), has facilitated in vitro investigation of human megakaryocytopoiesis. By confocal microscopy, endomitosis appeared as abortive mitosis skipping late stages of mitosis. No telophase and cytokinesis were observed. A spherical multipolar spindle which limits chromatid segregation was observed. The nuclear envelope subsequently reformed isolating all chromatids in a single nucleus. Platelet shedding was ultrastructurally studied. Platelet release occurred after formation of long cytoplasmic extensions (proplatelet formation), constriction areas delineating platelet territories. Heterogeneity in platelet size may be determined by the length of these extensions. Pegylated-recombinant human megakaryocyte growth and development factor, a truncated form of Mpl-L, was the most efficient cytokine to produce proplatelet-bearing megakaryocytes (MKs) and platelets in vitro. However, functional platelets with a normal ultrastructure could be produced in the presence of a combination of other cytokines. Finally, we investigated whether the induction of MK differentiation by the MS-5 stromal cell lines is due to Mpl-L. MS-5 cells synthesized Mpl-L transcripts and a biologically active protein. When human CD34+ cells were grown in contact or noncontact cultures with MS-5 cells, MK differentiation was observed. Soluble Mpl receptor (sMpl-Fc) addition inhibited MK growth, suggesting that the MK-promoting activity was due to Mpl-L production. Marrow stromal cell lines derived from TPO-/- mice were also able to sustain MK growth. Despite the absence of any production of Mpl-L, the sMpl-Fc continued to inhibit MK differentiation. This result suggests that the sMpl has a direct inhibitory effect and may explain the divergent results in the literature concerning the precise role of Mpl-L on the MK terminal differentiation.