A 3-year evaluation of preclinicaltrials.eu reveals room for improvement in preregistration of animal studies.

In 2018, the first registry dedicated to preregistration of animal study protocols was launched. Despite international support, the overall number of (pre)registered protocols is still low, illustrating the need for pushing the preregistration agenda among researchers and policymakers.

Translational Research in Cardiovascular Repair: A Call for a Paradigm Shift.

The international consortium TACTICS (Transnational Alliance for Regenerative Therapies in Cardiovascular Syndromes) has recently addressed key priorities in the field of cell-based therapy for cardiac repair, identifying the efficacy of translational research as one of the main challenges to ultimately improve the quality of life of patients with ischemic disease. Much of the controversy and confusion surrounding cardiac regenerative therapy stems from insufficient rigor in the conduct of preclinical studies, and there is an increasing recognition of a number of problems that undermine its quality that may contribute to translational failure. Here, we introduce well defined stages for preclinical research, and put forth proposals that should promote more rigorous preclinical work, in an effort to improve its quality and translatability. To augment the utility of preclinical research and its translation, it is necessary to (1) improve the quality of preclinical research, (2) promote collaborative efforts, and (3) enhance the sharing of knowledge and protocols. In particular, confirmatory (stage III) preclinical studies should be considered as a preamble to clinical studies and therefore must adhere to their standards of quality (including internal validity, standardization of protocols, and multicenter design). To increase transparency and minimize bias, these studies should be prospectively registered in an independent, open database. Ultimately, these recommendations should be implemented in the daily routine of investigators and in the policies of institutions, journals, and funding agencies.

Preregistration of animal research protocols: development and 3-year overview of preclinicaltrials.eu.

Open, prospective registration of a study protocol can improve research rigour in a number of ways. Through preregistration, key features of the study's methodology are recorded and maintained as a permanent record, enabling comparison of the completed study with what was planned. By recording the study hypothesis and planned outcomes a priori, preregistration creates transparency and can reduce the risk of several common biases, such as hypothesising after results are known and outcome switching or selective outcome reporting. Second, preregistration raises awareness of measures to reduce bias, such as randomisation and blinding. Third, preregistration provides a comprehensive listing of planned studies, which can prevent unnecessary duplication and reduce publication bias. Although commonly acknowledged and applied in clinical research since 2000, preregistration of animal studies is not yet the norm. In 2018 we launched the first dedicated, open, online register for animal study protocols: wwwpreclinicaltrialseu. Here, we provide insight in the development of preclinicaltrials.eu (PCT) and evaluate its use during the first 3 years after its launch. Furthermore, we elaborate on ongoing developments such as the rise of comparable registries, increasing support for preregistration in the Netherlands-which led to the funding of PCT by the Dutch government-and pilots of mandatory preregistration by several funding bodies. We show the international coverage of currently registered protocols but with the overall low number of (pre)registered protocols.

Publication rate in preclinical research: a plea for preregistration.

OBJECTIVES: The ultimate goal of biomedical research is the development of new treatment options for patients. Animal models are used if questions cannot be addressed otherwise. Currently, it is widely believed that a large fraction of performed studies are never published, but there are no data that directly address this question. METHODS: We have tracked a selection of animal study protocols approved in the University Medical Center Utrecht in the Netherlands, to assess whether these have led to a publication with a follow-up period of 7 years. RESULTS: We found that 60% of all animal study protocols led to at least one publication (full text or abstract). A total of 5590 animals were used in these studies, of which 26% was reported in the resulting publications. CONCLUSIONS: The data presented here underline the need for preclinical preregistration, in view of the risk of reporting and publication bias in preclinical research. We plea that all animal study protocols should be prospectively registered on an online, accessible platform to increase transparency and data sharing. To facilitate this, we have developed a platform dedicated to animal study protocol registration: www.preclinicaltrials.eu.

Fracture of the Sesamoid Bone of the Thumb: A Case Report and Review of the Literature.

CASE: Fracture of a sesamoid bone of the thumb is rare. We report a case of such a fracture after hyperextension of the thumb in a 26-year-old woman. After a volar plate injury was excluded, she was treated nonoperatively with 5 weeks of immobilization followed by physical therapy. CONCLUSION: After reviewing the current literature describing sesamoid fractures of the thumb, we recommend that fracture of the sesamoid of the metacarpophalangeal (MCP) joint should be regarded as an avulsion fracture. The role of surgical intervention should be limited to patients with a painful nonunion.

Lower retention after retrograde coronary venous infusion compared with intracoronary infusion of mesenchymal stromal cells in the infarcted porcine myocardium.

BACKGROUND: Commonly used strategies for cell delivery to the heart are intramyocardial injection and intracoronary (IC) infusion, both having their advantages and disadvantages. Therefore, alternative strategies, such as retrograde coronary venous infusion (RCVI), are explored. The aim of this confirmatory study was to compare cardiac cell retention between RCVI and IC infusion. As a secondary end point, the procedural safety of RCVI is assessed. METHODS: Four weeks after myocardial infarction, 12 pigs were randomised to receive mesenchymal stromal cells, labelled with Indium-111, via RCVI (n=6) or IC infusion (n=6). Four hours after cell administration, nuclear imaging was performed to determine the number of cells retained in the heart both in vivo and ex vivo. Procedure-related safety measures were reported. RESULTS: Cardiac cell retention is significantly lower after RCVI compared with IC infusion (in vivo: RCVI: median 2.89% vs IC: median 13.74%, p=0.002, ex vivo: RCVI: median 2.55% vs IC: median 39.40%, p=0.002). RCVI led to development of pericardial fluid and haematomas on the frontal wall of the heart in three cases. Coronary venous dissection after RCVI was seen in three pigs, of which one also developed pericardial fluid and a haematoma. IC infusion led to no flow in one pig. CONCLUSION: RCVI is significantly less efficient in delivering cells to the heart compared with IC infusion. RCVI led to more procedure-related safety issues than IC infusion, with multiple cases of venous dissection and development of haematomas and pericardial fluid collections.

Validation of a novel stand-alone software tool for image guided cardiac catheter therapy.

Comparison of the targeting accuracy of a new software method for MRI-fluoroscopy guided endomyocardial interventions with a clinically available 3D endocardial electromechanical mapping system. The new CARTBox2 software enables therapy target selection based on infarction transmurality and local myocardial wall thickness deduced from preoperative MRI scans. The selected targets are stored in standard DICOM datasets. Fusion of these datasets with live fluoroscopy enables real-time visualization of MRI defined targets during fluoroscopy guided interventions without the need for external hardware. In ten pigs (60-75 kg), late gadolinium enhanced (LGE) MRI scans were performed 4 weeks after a 90-min LAD occlusion. Subsequently, 10-16 targeted fluorescent biomaterial injections were delivered in the infarct border zone (IBZ) using either the NOGA 3D-mapping system or CARTBox2. The primary endpoint was the distance of the injections to the IBZ on histology. Secondary endpoints were total procedure time, fluoroscopy time and dose, and the number of ventricular arrhythmias. The average distance of the injections to the IBZ was similar for CARTBox2 (0.5 ± 3.2 mm) and NOGA (- 0.7 ± 2.2 mm; p = 0.52). Injection procedures with CARTBox2 and NOGA required 69 ± 12 and 60 ± 17 min, respectively (p = 0.36). The required endocardial mapping procedure with NOGA prior to injections, leads to a significantly longer total procedure time (p < 0.001) with NOGA. Fluoroscopy time with NOGA (18.7 ± 11.0 min) was significantly lower than with CARTBox2 (43.4 ± 6.5 min; p = 0.0003). Procedures with CARTBox2 show a trend towards less ventricular arrhythmias compared to NOGA. CARTBox2 is an accurate and fast software-only system to facilitate cardiac catheter therapy based on gold standard MRI imaging and live fluoroscopy.

Retrograde Coronary Venous Infusion as a Delivery Strategy in Regenerative Cardiac Therapy: an Overview of Preclinical and Clinical Data.

An important aspect of cell therapy in the field of cardiac disease is safe and effective delivery of cells. Commonly used delivery strategies such as intramyocardial injection and intracoronary infusion both present with advantages and disadvantages. Therefore, alternative delivery routes are explored, such as retrograde coronary venous infusion (RCVI). Our aim is to evaluate safety and efficiency of RCVI by providing a complete overview of preclinical and clinical studies applying RCVI in a broad range of disease types and experimental models. Available data on technical and safety aspects of RCVI are incomplete and insufficient. Improvement of cardiac function is seen after cell delivery via RCVI. However, cell retention in the heart after RCVI appears inferior compared to intracoronary infusion and intramyocardial injection. Adequately powered confirmatory studies on retention rates and safety are needed to proceed with RCVI in the future.

Standardized mean differences cause funnel plot distortion in publication bias assessments.

Meta-analyses are increasingly used for synthesis of evidence from biomedical research, and often include an assessment of publication bias based on visual or analytical detection of asymmetry in funnel plots. We studied the influence of different normalisation approaches, sample size and intervention effects on funnel plot asymmetry, using empirical datasets and illustrative simulations. We found that funnel plots of the Standardized Mean Difference (SMD) plotted against the standard error (SE) are susceptible to distortion, leading to overestimation of the existence and extent of publication bias. Distortion was more severe when the primary studies had a small sample size and when an intervention effect was present. We show that using the Normalised Mean Difference measure as effect size (when possible), or plotting the SMD against a sample size-based precision estimate, are more reliable alternatives. We conclude that funnel plots using the SMD in combination with the SE are unsuitable for publication bias assessments and can lead to false-positive results.