Animal models have provided invaluable information in the pursuit of medical knowledge and alleviation of human suffering. The foundations of our basic understanding of disease pathophysiology and ...human anatomy can largely be attributed to preclinical investigations using various animal models. Recently, however, the scientific community, citing concerns about animal welfare as well as the validity and applicability of outcomes, has called the use of animals in research into question. In this review, we seek to summarize the current state of the use of animal models in research.
•The use of animal models has been called into question by the scientific community.•Study design, statistical analysis, choice of animal model, and translation to human research remain areas of concern.•We review the current state of animals in research, with an emphasis on the 3Rs.•Future alternatives to the use of animals in research should be sought.
An inclusive contemporary analysis of spinal cord injury (SCI) rates in patients undergoing aneurysm repair and the factors associated with complications has not been performed.
Following a ...systematic literature search, studies from 2008 to 2018 on repair of descending thoracic aneurysm (DTA) and thoracoabdominal aortic aneurysm (TAAA) were pooled in a meta-analysis performed using the generic inverse variance method. The primary outcome was permanent SCI. Secondary outcomes were temporary SCI, operative mortality, long-term mortality, postoperative stroke, and cerebrospinal fluid (CSF) drain-related complications.
One-hundred sixty-nine studies (22,634 patients) were included. The pooled rate of permanent SCI was 4.5% (95% confidence interval CI, 3.8-5.4); 3.5% (95% CI, 1.8-6.7) for DTA and 7.6% (96% CI, 6.2-9.3) for TAAA repair (P for subgroups = .02), 5.7% (95% CI, 4.3-7.5) for open repair and 3.9% (95% CI, 3.1-4.8) for endovascular repair (P for subgroups = .03). Rates for Crawford extents I, II, III, IV, and V aneurysms were 4.0% (95% CI, 3.0-5.0), 15.0% (95% CI, 10.0-22.0), 7.0% (95% CI, 6.0-9.0), 2.0% (95% CI, 2.0-4.0), and 7.0% (95% CI, 2.0-23.0) respectively (P for subgroups <.001). The pooled rates for operative mortality, late mortality at a mean follow-up of 5.0 years, stroke, and temporary SCI were 7.4% (95% CI, 6.1-9.4), 1.0% (95% CI, 0.0-1.0), 4.2% (95% CI, 3.6-4.8), and 3.7% (95% CI, 3.0-4.6), respectively. The pooled rates for severe, moderate, and minor CSF-drain related complications were 5.1% (95% CI, 2.23-11.1), 4.1% (95% CI, 0.6-22.0), and 3.6% (95% CI, 1.2-8.0) respectively.
Despite improvement, both open and endovascular aneurysm repair remain associated with a substantial risk of permanent SCI. The risk is greater for TAAA repair, especially extent II, III, and V.
Key study findings. DTA, Descending thoracic; TAAA, thoracoabdominal aortic aneurysms. Display omitted
Abstract
Aims
Data suggest that women have worse outcomes than men after coronary artery bypass grafting (CABG), but results have been inconsistent across studies. Due to the large differences in ...baseline characteristics between sexes, suboptimal risk adjustment due to low-quality data may be the reason for the observed differences. To overcome this limitation, we undertook a systematic review and pooled analysis of high-quality individual patient data from large CABG trials to compare the adjusted outcomes of women and men.
Methods and results
The primary outcome was a composite of all-cause mortality, myocardial infarction (MI), stroke, and repeat revascularization (major adverse cardiac and cerebrovascular events, MACCE). The secondary outcome was all-cause mortality. Multivariable mixed-effect Cox regression was used. Four trials involving 13 193 patients (10 479 males; 2714 females) were included. Over 5 years of follow-up, women had a significantly higher risk of MACCE adjusted hazard ratio (HR) 1.12, 95% confidence interval (CI) 1.04–1.21; P = 0.004 but similar mortality (adjusted HR 1.03, 95% CI 0.94–1.14; P = 0.51) compared to men. Women had higher incidence of MI (adjusted HR 1.30, 95% CI 1.11–1.52) and repeat revascularization (adjusted HR 1.22, 95% CI 1.04–1.43) but not stroke (adjusted HR 1.17, 95% CI 0.90–1.52). The difference in MACCE between sexes was not significant in patients 75 years and older. The use of off-pump surgery and multiple arterial grafting did not modify the difference between sexes.
Conclusions
Women have worse outcomes than men in the first 5 years after CABG. This difference is not significant in patients aged over 75 years and is not affected by the surgical technique.
Graphical Abstract
Risk of major adverse cardiac and cerebrovascular events (all-cause mortality/myocardial infarction/stroke/repeat revascularization) in women vs. men undergoing coronary artery bypass surgery (curves represent unadjusted estimates). HR, hazard ratio; MACCE, major adverse cardiac and cerebrovascular events; MI, myocardial infarction.
Cerebral protection strategies in aortic arch surgery: A network meta-analysis Hameed, Irbaz; Rahouma, Mohamed; Khan, Faiza M. ...
Journal of thoracic and cardiovascular surgery/The Journal of thoracic and cardiovascular surgery/The journal of thoracic and cardiovascular surgery,
January 2020, 2020-Jan, 2020-01-00, 20200101, Volume:
159, Issue:
1
Journal Article
Peer reviewed
Open access
Cerebral protection for aortic arch surgery has been widely studied, but comparisons of all the available strategies have rarely been performed. We performed direct and indirect comparisons of ...antegrade cerebral perfusion, retrograde cerebral perfusion, and deep hypothermic circulatory arrest in a network meta-analysis.
After a systematic literature search, studies comparing any combination of antegrade cerebral perfusion, retrograde cerebral perfusion, and deep hypothermic circulatory arrest were included, and a frequentist network meta-analysis was performed using the generic inverse variance method. The primary outcomes were postoperative stroke and operative mortality. Secondary outcomes were postoperative transient neurologic deficits, myocardial infarction, respiratory complications, and renal failure.
A total of 68 studies were included with a total of 26,968 patients. Compared with deep hypothermic circulatory arrest, both antegrade cerebral perfusion and retrograde cerebral perfusion were associated with significantly lower postoperative stroke and operative mortality rates: antegrade cerebral perfusion (odds ratio OR, 0.62; 95% confidence interval CI, 0.51-0.75; and OR, 0.63, 95% CI, 0.51-0.76, respectively) and retrograde cerebral perfusion (OR, 0.66; 95% CI, 0.54-0.82; and OR, 0.57; 95% CI, 0.45-0.71, respectively). Antegrade cerebral perfusion and retrograde cerebral perfusion were associated with similar incidence of primary outcomes. No difference among the 3 techniques was found in secondary outcomes. At meta-regression, circulatory arrest duration correlated with the neuroprotective effect of antegrade cerebral perfusion and retrograde cerebral perfusion compared with deep hypothermic circulatory arrest. Unilateral or bilateral antegrade cerebral perfusion and arrest temperature did not influence the results.
Antegrade cerebral perfusion and retrograde cerebral perfusion are associated with better postoperative outcomes compared with deep hypothermic circulatory arrest, and the relative benefit increases with the duration of the circulatory arrest. No differences between antegrade cerebral perfusion and retrograde cerebral perfusion were found for all the explored outcomes.
Contemporary outcomes of open repair of thoracoabdominal aortic aneurysms (TAAAs) and descending thoracic aortic aneurysms (DTAs) have not been analyzed in an inclusive meta-analysis.
After a ...systematic literature search, studies from 2008 to 2018 reporting outcomes of open repair of DTAs or TAAAs were pooled in a single-arm meta-analysis performed using the generic inverse variance method. Primary outcome was operative mortality. Secondary outcomes were late mortality, postoperative stroke, permanent and temporary spinal cord injury, renal failure, respiratory failure, and myocardial infarction.
Fifty-four studies with 12,245 patients were included. Pooled operative mortality for open repair was 10.4% (95% confidence interval CI, 8.3-12.8): 6.6% (95% CI, 3.7-11.6) for DTA and 10.5% (95% CI, 7.5-14.5) for TAAA. Pooled incidence rate of late mortality was 0.6% (95% CI, 0.5-0.8) per person-year. Pooled rates for postoperative outcomes were 4.9% (95% CI, 3.9-6.1) for stroke; 5.7% (95% CI, 4.3-7.5) and 3.0% (95% CI, 2.1-4.2) for permanent and temporary spinal cord injury, respectively; 13.2% (95% CI, 9.9-17.3) for renal failure; 23.3% (95% CI, 17.5-30.4) for respiratory failure; and 2.7% (95% CI, 1.8-4.1) for myocardial infarction. At metaregression, year of publication, use of the clamp-and-sew technique, and use of the cerebrospinal fluid drain were associated with lower operative mortality. Ruptured aneurysms were associated with higher operative mortality.
Despite improvement, open repair of DTAs and TAAAs continues to be associated with a considerable risk for operative death and perioperative complications. Use of the cerebrospinal fluid drain is associated with better outcomes.
Acute postoperative myocardial ischemia (PMI) after cardiac surgery is an infrequent event that can evolve rapidly and become a potentially life-threatening complication. Multiple factors are ...associated with acute PMI after cardiac surgery and may vary by the type of surgical procedure performed. Although the criteria defining nonprocedural myocardial ischemia are well established, there are no universally accepted criteria for the diagnosis of acute PMI. In addition, current evidence on the management of acute PMI after cardiac surgery is sparse and generally of low methodological quality. Once acute PMI is suspected, prompt diagnosis and treatment are imperative, and options range from conservative strategies to percutaneous coronary intervention and redo coronary artery bypass grafting. In this document, a multidisciplinary group including experts in cardiac surgery, cardiology, anesthesiology, and postoperative care summarizes the existing evidence on diagnosis and treatment of acute PMI and provides clinical guidance.
Objectives
Atrial functional mitral regurgitation (AFMR) is a subtype of functional mitral regurgitation due to longstanding atrial fibrillation (AF) or heart failure with preserved ejection ...fraction. The variation in AFMR' definition and the common mode of treatment described in the literature remain unknown.
Methods
We performed a scoping review of studies that surgically treated AFMR to characterize the existing variability in the definition of AFMR, the type of operations performed for AFMR valvulopathy, and the treatment for the chronic AF. We searched Medline, EMBASE, Cochrane Library, Scopus, and Web of Science since their inceptions for studies of patients affected by AFMR and surgically treated for their valvulopathy.
Results
Twelve studies (n = 494 patients) met eligibility criteria. All studies excluded patients with signs of left ventricular (LV) dysfunction, but the way additional parameters were used to define AFMR at a more granular level varied across studies: nine studies (75%) used the presence of AF to define their AFMR cohorts, with five (41.2%) requiring a history of AF of >1 year; additionally, the threshold values for the LV ejection fraction differed (45%–55%). Isolated mitral annuloplasty was performed in 96.2% of patients. Broad variability was detected in the proportion of patients undergoing the Cox‐Maze procedure (range, 17.8%–79.5%), pulmonary vein isolation (0.0%–66.7%), and left atrial appendage ligation (0.0%–100.0%).
Conclusions
AFMR remains variably defined in surgical studies, making comparisons across studies difficult. Mitral annuloplasty was most commonly performed. The proportion of AFMR patients undergoing concomitant procedures for AF varied substantially.
Background Several randomized trials have compared the patency of coronary artery bypass conduits. All of the published studies, however, have performed pairwise comparisons and a comprehensive ...evaluation of the patency rates of all conduits has yet to be published. We set out to investigate the angiographic patency rates of all conduits used in coronary bypass surgery by performing a network meta-analysis of the current available randomized evidence. Methods and Results A systematic literature search was conducted for randomized controlled trials comparing the angiographic patency rate of the conventionally harvested saphenous vein, the no-touch saphenous vein, the radial artery (RA), the right internal thoracic artery, or the gastroepiploic artery. The primary outcome was graft occlusion. A total of 4160 studies were retrieved of which 14 were included with 3651 grafts analyzed. The weighted mean angiographic follow-up was 5.1 years. Compared with the conventionally harvested saphenous vein, both the RA (incidence rate ratio IRR 0.54; 95% CI, 0.35-0.82) and the no-touch saphenous vein (IRR 0.55; 95% CI, 0.39-0.78) were associated with lower graft occlusion. The RA ranked as the best conduit (rank score for RA 0.87 versus 0.85 for no-touch saphenous vein, 0.23 for right internal thoracic artery, 0.29 for gastroepiploic artery, and 0.25 for the conventionally harvested saphenous vein). Conclusions Compared with the conventionally harvested saphenous vein, only the RA and no-touch saphenous vein grafts are associated with significantly lower graft occlusion rates. The RA ranks as the best conduit. Registration URL: https://www.crd.york.ac.uk/prospero; Unique identifier: CRD42020164492.
Background
Quality of the peer‐review process has been tested only in small studies. We describe and summarize the randomized trials that investigated interventions aimed at improving peer‐review ...process of biomedical manuscripts.
Methods and Results
All randomized trials comparing different peer‐review interventions at author‐, reviewer‐, and/or editor‐level were included. Differences between traditional and intervention‐modified peer‐review processes were pooled as standardized mean difference (SMD) in quality based on the definitions used in the individual studies. Main outcomes assessed were quality and duration of the peer‐review process. Five‐hundred and seventy‐five studies were retrieved, eventually yielding 24 randomized trials. Eight studies evaluated the effect of interventions at author‐level, 16 at reviewer‐level, and 3 at editor‐level. Three studies investigated interventions at multiple levels. The effects of the interventions were reported as mean change in review quality, duration of the peer‐review process, acceptance/rejection rate, manuscript quality, and number of errors detected in 13, 11, 5, 4, and 3 studies, respectively. At network meta‐analysis, reviewer‐level interventions were associated with a significant improvement in review quality (SMD, 0.20 0.06 to 0.33), at the cost of increased duration of the review process (SMD, 0.15 0.01 to 0.29), except for reviewer blinding. Author‐ and editor‐level interventions did not significantly impact peer‐review quality and duration (respectively, SMD, 0.17 −0.16 to 0.51 and SMD, 0.19 −0.40 to 0.79 for quality, and SMD, 0.17 −0.16 to 0.51 and SMD, 0.19 −0.40 to 0.79 for duration).
Conclusions
Modifications of the traditional peer‐review process at reviewer‐level are associated with improved quality, at the price of longer duration. Further studies are needed.
Registration
URL:
https://www.crd.york.ac.uk/prospero
; Unique identifier: CRD42020187910.