Thrombocytopenia after sutureless and standard stented aortic valve replacement: a retrospective analysis of risk factors, clinical course, and early outcome

OBJECTIVES

Thrombocytopenia following Perceval aortic valve replacement has been described previously with variable outcome. Studies have lacked a robust analysis of platelet fluctuation and factors affecting it. We aimed to statistically describe the trend in thrombocyte variability as compared with conventional aortic valve replacement, and to assess predictors as well as impact on associated outcomes.

METHODS

One hundred consecutive patients with first-time Perceval were retrospectively compared to 219 patients after Perimount Magna Ease valve replacement. The primary outcome was the serial thrombocyte count on day 0-6. Generalized estimating equations were used to analyse the data using fixed-effect models: for the effect of the post-operative day on platelet count, and random-effect models estimating both time-variant (platelets) and time in-variant variables (valve type, age, LV function, pre-op platelet level).

RESULTS

Perceval patients were older (72 ± 1 vs 68 ± 1 years, p < 0.01) with higher NYHA status (3(2-3) vs 2(1-2), p < 0.001). Mean platelet count in the sutureless group was lowest on day 2 (91.9 ± 31.6 vs 121.7 ± 53.8 × 103 µl-1), and lower on day 4 (97.9 ± 44) and 6 (110.6 ± 61) compared to the conventional group (157.2 ± 60 and 181.7 ± 79) but did not result in a higher number of transfusions, bleeding or longer hospital stay (p > 0.05). Reduced platelet count was a strong predictor of red cell transfusion in the conventional (p = 0.016), but not in the sutureless group (p = 0.457). Age (Coef -1.025, 95%CI-1.649--0.401, p < 0.001) and CPB-time (Coef 0.186, 95%CI-0.371--0.001, p = 0.048) were predictors for lower platelet levels.

CONCLUSION

Considering the older patient profile treated with Perceval, postoperative thrombocytopenia does not impact on outcome in terms of transfusions, complications or hospital stay.

Transcriptomic Analysis of Tight Junction Proteins Demonstrates the Aberrant Expression and Function of Zona Occludens 2 (ZO-2) Protein in Stanford Type A Aortic Dissection

OBJECTIVE

Thoracic aortic aneurysm dissection (TAAD) represents a cardiac surgery emergency characterized by the disrupted integrity of the aortic wall and is associated with poor prognosis. In this context, the identification of biomarkers implicated in the pathobiology of TAAD is crucial. Our aim in the present original in silico study is to assess the differential gene expression profile of the tight junction proteins (TJPs) in patients with TAAD and to propose novel biomarkers for the diagnosis and prognosis of this disease.

METHODS

We implemented bioinformatics methodology in order to construct the gene network of the TJPs family, identify the differentially expressed genes (DEGs) in pathologic aortic tissue excised from patients with TAAD as compared to healthy aortic tissue, and assess the related biological functions and the associated miRNA families.

RESULTS

Data regarding the transcriptomic profile of selected genes were retrieved and incorporated from three microarray datasets, including 23 TAAD and 20 healthy control samples. A total of 32 TJPs were assessed. The zona occludens 2 (ZO-2) protein encoded by the gene TJP2 was significantly under-expressed in patients with TAAD compared to the control group (p = 0.009). ZO-2 was associated with fair discrimination and calibration traits in predicting the TAAD presentation. CpG islands of ZO-2 were demonstrated. No important difference was found regarding ZO-2 expression between aneurysmal non-dissected and healthy control aortic tissue. Finally, we performed gene set enrichment analysis (GSEA) and uncovered the major biological functions and miRNA families (hsa-miR-155-5p, hsa-miR-1-3p, hsa-miR-2118-5p, hsa-miR-4691-3p, and hsa-miR-1229-3p) relevant to ZO-2.

CONCLUSIONS

These outcomes demonstrated the important role of ZO-2 in the pathobiology of TAAD.

Sex-Based Differences in Early Outcomes Following Mitral Valve Surgery for Degenerative Disease

OBJECTIVES

To determine whether sex-based differences exist following surgery for degenerative mitral valve disease.

METHODS

Using a national database, we analysed data on mitral valve surgery for degenerative disease (n = 22,658) between January 2000 and March 2019 in the UK. We split the cohort into men (n = 14,681) and women (n = 7977) and compared background characteristics, intraoperative variables and early postoperative outcomes. Our primary outcome was hospital mortality; secondary outcomes included re-exploration for bleeding, prolonged admission (>10 days) and mitral replacement. We used binary logistic regression models for all outcomes, with multiplicative interaction terms to determine the nature of any differences.

RESULTS

Women presented older (70 ± 11 years vs. 67 ± 11 years, p < 0.001) with worse symptom profiles (New York Heart Association Class III-IV 57% vs. 44%, p < 0.001). They had higher rates of preoperative atrial fibrillation (39% vs. 35%, p < 0.001) and tricuspid disease requiring surgery (21% vs. 15%, p < 0.001). They had lower repair rates (66% vs. 76%, p < 0.001), higher mortality (3% vs. 2%, p < 0.001) and were more likely to have a prolonged admission (48% vs. 40%, p < 0.001). Female sex was an independent predictor of mortality (odds ratio (OR): 1.52, 95% CI: 1.21-1.90, p < 0.001). Age and Canadian Cardiovascular Society (CCS) score showed significant interactions with sex. The relationship between advancing age and mortality was found to be more pronounced in women.

CONCLUSIONS

(1) Female sex is an independent predictor of hospital mortality, prolonged hospital admission and mitral valve replacement. (2) The relationship between female sex and mortality is exacerbated by worsening CCS score and advancing age. (3) Women have significantly lower repair rates.

Predictors of outcome after CABG in the South-Asian community: a propensity matched analysis

BACKGROUND

Ethnicity is not incorporated into standardized pre-operative risk-stratification tools for cardiac surgery. This study compared short-term outcomes following coronary artery bypass graft (CABG) surgery in South Asian and non-Asian patients.

METHODS

Consecutive patients undergoing isolated CABG surgery via sternotomy between the years 2011 and 2019 were retrospectively analyzed. Initially, 1957 patients were identified (799 South-Asian, 40.8%). The patient groups were then propensity matched according to 10 relevant pre-operative covariates (age, body mass index, pulmonary disease, renal failure, smoking, diabetes, ventricular function, renal failure): 675 non-Asian patients were matched against 675 Asian patients.

RESULTS

Operative mortality was 1.77% and similar between the two groups (p = 0.447). Multivariate regression analysis found predictors of operative mortality to be pre-operative serum creatinine, age, left ventricular (LV) impairment, and extent of coronary disease. The effect of creatinine on mortality was selective for South-Asian patients (p = 0.015). LV impairment was a predictor of mortality in non-Asian patients, however this effect did not exist in South-Asian patients. Predictors of short-term complications (composite of death, stroke, reoperation, hemofiltration, and pneumonia) were age and creatinine (coefficient 0.002, 95% CI 0.0004-0.004, p = 0.019) in the overall cohort. Subgroup analysis found age to remain a selective negative predictor of complications in South-Asian patients. Cox regression analysis found creatinine, age, and LVEF to influence 10-year survival, whilst ethnicity was not a predictor.

CONCLUSION

This study highlights the cumulative risk associated with ethnicity and renal disease in predicting short-term outcomes following CABG. This warrants further investigations in larger populations, thus guiding pre-operative risk-stratification.

Infective endocarditis: Do we have an effective risk score model? A systematic review

Background

Infective endocarditis (IE) is a rare, highly morbid condition with 17% in-hospital mortality. A total of 25-30% require surgery and there is ongoing debate with regard to markers predicting patient outcomes and guiding intervention. This systematic review aims to evaluate all IE risk scores currently available.

Methods

Standard methodology (PRISMA guideline) was used. Papers with risk score analysis for IE patients were included, with attention to studies reporting area under the receiver-operating characteristic curve (AUC/ROC). Qualitative analysis was carried out, including assessment of validation processes and comparison of these results to original derivation cohorts where available. Risk-of-bias analysis illustrated according to PROBAST guidelines.

Results

Of 75 articles initially identified, 32 papers were analyzed for a total of 20 proposed scores (range 66-13,000 patients), 14 of which were specific for IE. The number of variables per score ranged from 3 to 14 with only 50% including microbiological variables and 15% including biomarkers. The following scores had good performance (AUC > 0.8) in studies proposing the score (often the derivation cohort); however fared poorly when applied to a new cohort: PALSUSE, DeFeo, ANCLA, RISK-E, EndoSCORE, MELD-XI, COSTA, and SHARPEN. DeFeo score demonstrated the largest discrepancy with initial AUC of 0.88, compared to 0.58 when applied to different cohorts. The inflammatory response in IE has been well documented and CRP has been found to be an independent predictor for worse outcomes. There is ongoing investigation on alternate inflammatory biomarkers which may assist in IE management. Of the scores identified in this review, only three have included a biomarker as a predictor.

Conclusion

Despite the variety of available scores, their development has been limited by small sample size, retrospective collection of data and short-term outcomes, with lack of external validation, limiting their transportability. Future population studies and large comprehensive registries are required to address this unmet clinical need.

Renal outcomes in valve-in-valve transcatheter versus redo surgical aortic valve replacement: A systematic review and meta-analysis

INTRODUCTION

Postoperative acute kidney injury (AKI) and the requirement for renal replacement therapy (RRT) remain common and significant complications of both transcatheter valve-in-valve aortic valve replacement (ViV-TAVR) and redo surgical aortic valve replacement (SAVR). Nevertheless, the understanding of renal outcomes in the population undergoing either redo SAVR or ViV-TAVR remains controversial.

METHODS

A systematic database search with meta-analysis was conducted of comparative original articles of ViV-TAVR versus redo SAVR in EMBASE, MEDLINE, Cochrane database, and Google Scholar, from inception to September 2021. Primary outcomes were AKI and RRT. Secondary outcomes were stroke, major bleeding, pacemaker implantation rate, operative mortality, and 30-day mortality.

RESULTS

Our search yielded 5435 relevant studies. Eighteen studies met the inclusion criteria with a total of 11,198 patients. We found ViV-TAVR to be associated with lower rates of AKI, postoperative RRT, major bleeding, pacemaker implantation, operative mortality, and 30-day mortality. No significant difference was observed in terms of stroke rate. The mean incidence of AKI in ViV-TAVR was 6.95% (±6%) and in redo SAVR was 15.2% (±9.6%). For RRT, our data showed that VIV-TAVR to be 1.48% (±1.46%) and redo SAVR to be 8.54% (±8.06%).

CONCLUSION

Renoprotective strategies should be put into place to prevent and reduce AKI incidence regardless of the treatment modality. Patients undergoing re-intervention for the aortic valve constitute a high-risk and frail population in which ViV-TAVR demonstrated it might be a feasible option for carefully selected patients. Long-term follow-up data and randomized control trials will be needed to evaluate mortality and morbidity outcomes between these 2 treatments.

Are there differences in cardiothoracic surgery performed by trainees versus fully trained surgeons?

OBJECTIVES

We sought to assess the safety of training in cardiothoracic surgery comparing outcomes of cases performed by trainees versus fully trained surgeons.

METHODS

EmBase, Scopus, PubMed, and OVID MEDLINE were searched in August 2021 independently by two authors. A third author arbitrated decisions to resolve disagreements. Inclusion criteria were articles on cardiothoracic surgery reporting on outcomes for trainees. Studies were assessed for appropriateness as per CBEM criteria. Eight hundred and ninety-two results were obtained, 27 represented best evidence (2-meta-analyses, 1-RCT, and 24 retrospective cohort studies).

RESULTS

In all 474,160 operative outcomes were assessed for 434,535 coronary artery bypass grafting (CABG) (431,329 on-pump vs. 3206 off-pump), 3090 AVR, 1740 MVR/repair, 26,433 mixed, 3565 congenital, and 4797 thoracic procedures. In all 398,058 cases were performed by trainees and 75,943 by consultants. One hundred fifty-nine cases were indeterminate. There were no statistically significant differences in the patients' preoperative risk scores. All studies excluded extreme high-risk patients in emergency setting, patients with poor left ventricular function, and reoperation cases that were undertaken by consultants. There were no differences in cardiopulmonary bypass and clamp times for CABG. Times for valve replacement and repair cases were longer for trainees. There were no differences in the postoperative outcomes including perioperative myocardial infarction, resternotomy for bleeding, stroke, renal failure, intensive therapy unit length of stay, and total length of stay. One study reported no differences on angiographic graft patency at 1 year. There were no differences in in-hospital or midterm mortality out to 5-years.

DISCUSSION

Trainees can perform cardiothoracic surgery in dedicated high-volume units with outcomes comparable to those of fully trained surgeons.

Use of Cytokine Filters During Cardiopulmonary Bypass: Systematic Review and Meta-Analysis

INTRODUCTION

Cardiac surgery involving cardiopulmonary bypass (CPB) activates an inflammatory response releasing cytokines that are associated with less favourable outcomes. This study aims to compare i) CPB during cardiac surgery (control) versus ii) CPB with haemoadsorption therapy; and assess the effect of adding this therapy in reducing the inflammatory cytokines burden.

METHODS

A systematic literature review with metanalysis was conducted regarding the main outcomes (operative mortality, ventilation duration, intensive care unit [ICU] and hospital stays) and day-1 inflammatory markers levels post-surgery. Fifteen (15) studies were included for final analysis (eight randomised controlled trials, seven observational studies) with no evidence of publication bias.

RESULTS

Subgroup analysis of non-elective surgeries across observational studies (emergency and infective endocarditis) significantly favoured cytokine filters in terms of 30-day mortality (OR 0.40, 95% CI 0.20, 0.83; p=0.01) and shorter ICU stay (MD -42.36, 95% CI -68.07, -16.65; p=0.001). At day-1 post-surgery, there was a significant difference favouring the cytokine filter group in c-reactive protein (CRP) (MD -0.71, 95% CI -0.84, -0.59; p<0.001) with no differences in white blood count (WBC), procalcitonin (PCT), tumour necrosis factor-alpha (TNF-α), IL-6, IL-8 and lactate. When comparing cytokine filters and control across all studies there was no significant difference in operative mortality, ventilation duration, hospital stay and ICU length of stay. Also, there were no statistical differences in randomised controlled trials (RCTs) using haemadsorption filters.

CONCLUSIONS

A significant reduction in 30-day mortality and ICU stay could be obtained by using haemadsorption therapy during non-elective cardiac surgery, especially emergency surgery and in patients with higher inflammatory burden such as infective endocarditis.

Machine learning and artificial intelligence in cardiac transplantation: A systematic review

Background

This review aims to systematically evaluate the currently available evidence investigating the use of artificial intelligence (AI) and machine learning (ML) in the field of cardiac transplantation. Furthermore, based on the challenges identified we aim to provide a series of recommendations and a knowledge base for future research in the field of ML and heart transplantation.

Methods

A systematic database search was conducted of original articles that explored the use of ML and/or AI in heart transplantation in EMBASE, MEDLINE, Cochrane database, and Google Scholar, from inception to November 2021.

Results

Our search yielded 237 articles, of which 13 studies were included in this review, featuring 463 850 patients. Three main areas of application were identified: (1) ML for predictive modeling of heart transplantation mortality outcomes; (2) ML in graft failure outcomes; (3) ML to aid imaging in heart transplantation. The results of the included studies suggest that AI and ML are more accurate in predicting graft failure and mortality than traditional scoring systems and conventional regression analysis. Major predictors of graft failure and mortality identified in ML models were: length of hospital stay, immunosuppressive regimen, recipient's age, congenital heart disease, and organ ischemia time. Other potential benefits include analyzing initial lab investigations and imaging, assisting a patient with medication adherence, and creating positive behavioral changes to minimize further cardiovascular risk.

Conclusion

ML demonstrated promising applications for improving heart transplantation outcomes and patient‐centered care, nevertheless, there remain important limitations relating to implementing AI into everyday surgical practices.

Rapid deployment technology versus conventional sutured bioprostheses in aortic valve replacement

Objectives

Despite the benefits of rapid deployment aortic valve prostheses (RDAVR), conventional sutured valves (cAVR) are more commonly used in the treatment for aortic stenosis. Given the paucity of randomized studies, this study aimed to synthesize available data to compare both treatment options.

Methods

A systematic search of Pubmed, OVID, and MEDLINE was conducted to retrieve comparative studies for RDAVR versus cAVR in the treatment of aortic stenosis. Out of 1773 returned titles, 35 papers were used in the final analysis, including 1 randomized study, 1 registry study, 6 propensity‐matched studies, and 28 observational studies, incorporating a total of 10,381 participants (RDAVR n = 3686; cAVR n = 6310).

Results

Random‐effects meta‐analysis found no difference between the two treatment groups in terms of operative mortality, stroke, or bleeding (p > .05). The RDAVR group had reduced cardiopulmonary bypass (standardized mean difference [SMD]: −1.28, 95% confidence interval [CI]: [−1.35, −1.20], p < .001) and cross‐clamp times (SMD: −1.05, 95% CI: [−1.12, −0.98], p < .001). Length of stay in the intensive care unit was also shorter in the RDAVR group (SMD: −0.385, 95% CI: [−0.679, −0.092], p = .010). The risk of pacemaker insertion was higher for RDAVR (odds ratio [OR]: 2.41, 95% CI: [1.92, 3.01], p < .001) as was the risk of paravalvular leak (PVL) at midterm follow‐up (OR: 2.52, 95% CI: [1.32, 4.79], p = .005). Effective orifice area and transvalvular gradient were more favorable in RDAVR patients (p > .05).

Conclusions

Despite the benefits of RDAVR in terms of reduced operative time and enhanced recovery, the risk of pacemaker insertion and midterm PVL remains a significant cause for concern.

Evaluation of Computational Methodologies for Accurate Prediction of Wall Shear Stress and Turbulence Parameters in a Patient-Specific Aorta

Background: Recent studies suggest that blood flow in main arteries is intrinsically disturbed, even under healthy conditions. Despite this, many computational fluid dynamics (CFD) analyses of aortic haemodynamics make the assumption of laminar flow, and best practices surrounding appropriate modelling choices are lacking. This study aims to address this gap by evaluating different modelling and post-processing approaches in simulations of a patient-specific aorta. Methods: Magnetic resonance imaging (MRI) and 4D flow MRI from a patient with aortic valve stenosis were used to reconstruct the aortic geometry and derive patient-specific inlet and outlet boundary conditions. Three different computational approaches were considered based on assumed laminar or assumed disturbed flow states including low-resolution laminar (LR-Laminar), high-resolution laminar (HR-Laminar) and large-eddy simulation (LES). Each simulation was ran for 30 cardiac cycles and post-processing was conducted on either the final cardiac cycle, or using a phase-averaged approach which utilised all 30 simulated cycles. Model capabilities were evaluated in terms of mean and turbulence-based parameters. Results: All simulation types, regardless of post-processing approach could correctly predict velocity values and flow patterns throughout the aorta. Lower resolution simulations could not accurately predict gradient-derived parameters including wall shear stress and viscous energy loss (largest differences up to 44.6% and 130.3%, respectively), although phase-averaging these parameters improved predictions. The HR-Laminar simulation produced more comparable results to LES with largest differences in wall shear stress and viscous energy loss parameters up to 5.1% and 11.6%, respectively. Laminar-based parameters were better estimated than turbulence-based parameters. Conclusion: Our findings suggest that well-resolved laminar simulations can accurately predict many laminar-based parameters in disturbed flows, but there is no clear benefit to running a HR-Laminar simulation over an LES simulation based on their comparable computational cost. Additionally, post-processing "typical" laminar simulation results with a phase-averaged approach is a simple and cost-effective way to improve accuracy of lower-resolution simulation results.

Mitral and tricuspid annuloplasty ring dehiscence: a systematic review with pooled analysis

 

OBJECTIVES

Mitral and tricuspid ring annuloplasty dehiscence with consequent recurrent valve regurgitation is a rare but challenging procedural failure. The incidence and predisposing risk factors for annuloplasty ring dehiscence include technical and pathological ones.

METHODS

A systematic database search with pooled analysis was conducted of original articles that only included dehiscence rate of mitral and tricuspid ring in EMBASE, MEDLINE, Cochrane database and Google Scholar, from inception to November 2020. The outcomes included were dehiscence rate in mitral and tricuspid, type of ring implanted, dehiscence rate by pathology and by ring size and shape.

RESULTS

Our search yielded 821 relevant studies. Thirty-three studies met the inclusion criteria with a total of 10 340 patients (6543 mitral, 1414 tricuspid) of which 87 (mitral) and 30 (tricuspid) had dehiscence. Overall, dehiscence rate was 1.43%, diagnosed at a median of 4.5 ± 1.0 months postoperatively. A significant difference in mitral dehiscence rate was found by ring type (semi-rigid 1.86%, rigid 2.32%; flexible 0.43%; P < 0.001). There was no significant difference in rate of dehiscence by ring size (P = 0.067) and shape in mitral (P = 0.281) but there was higher dehiscence rate in ischaemic compared to non-ischaemic mitral regurgitation (3.91% vs 1.63%; P = 0.022). Among tricuspid studies, 9 of 10 studies did not report any dehiscence.

CONCLUSIONS

Although rigid, semi-rigid and flexible annuloplasty rings provide acceptable valve repair outcomes, mitral annuloplasty ring dehiscence is clinically more common among rigid rings. Understanding the multifactorial nature of ring dehiscence will help in identifying the patients at high risk and improve their clinical outcomes.

The Use of Frailty Scoring to Predict Early Physical Activity Levels After Cardiac Surgery

BACKGROUND

Assessing patient fitness prior to high-risk operations is becoming increasingly vital in cardiothoracic surgery. Physical activity (PA) and frailty measures are powerful perioperative tools, albeit underused in clinical practice. This study aimed to assess the influence of patient frailty on PA postsurgery and other short-term outcomes.

METHODS

Eighty patients undergoing a variety of cardiac surgical procedures (coronary revascularisation, valve repair/replacement, or combination) were recruited to participate. The Reported Edmonton Frailty Scale was used to measure preoperative frailty. As objective measures of PA, participants wore a wrist accelerometer device for 14 days prior to their operation and early in the postoperative period for 30 days.

RESULTS

A global reduction in PA was observed in the early postoperative period. Frailty was a significant predictor of reduced light (coefficient -2.23, 95% CI -4.21 to -0.25, P = .028) and moderate activity (coefficient -1.85, 95% CI -2.99 to -0.70, P = .002) postoperatively. Neither frailty nor preoperative PA were predictors of postoperative composite complications. Both frailty (coefficient 0.134, 95% CI 0.106-0.162, P < .001) and PA scores (P < .05) were strong predictors of length of hospital stay (coefficient 1.76, 95% CI 0.003-3.524, P = .05). Furthermore, patients who stayed in hospital longer were more likely to suffer early postoperative complications (stroke, renal failure, reoperation, pacemaker) if they were frail (P < .0001) compared to non-frail patients (P = .607).

CONCLUSIONS

This study highlights the predictive ability of objective frailty scoring and PA measurement for outcomes after cardiac surgery. This has important implications for surgical risk stratification and personalized postoperative planning.

Aortic root replacement to treat type A aortic dissection: A comparison of midterm outcomes between composite valve grafts and porcine aortic roots

BACKGROUND

Porcine aortic roots (PAR) have been reported in the literature with acceptable short- and long-term outcomes for the treatment of aortic root aneurysms. However, their efficacy in type A aortic dissection (TAAD) is yet to be defined.

METHODS

Using data from a locally collated aortic dissection registry, we compared the outcomes in patients undergoing aortic root replacement for TAAD using either of two surgical options: (a) PAR or (b) composite valve grafts (CVG). A retrospective analysis was conducted for all procedures in the period from 2005 to 2018.

RESULTS

A total of 252 patients underwent procedures for TAAD in the time period. Sixty-five patients had aortic root replacements (PAR n = 30, CVG n = 35). Between-group comparisons identified a younger CVG group (50.5 vs 64.5, P < .05) although all other covariates were comparable. Operative parameters were comparable between the two groups. The use of PAR did not significantly impact operative mortality (odds ratio [OR], 0.93; 95% confidence interval [CI], 0.22-3.61; P = .992), stroke (OR, 2.91, 0.25-34.09, P = .395), reoperation (OR, 0.91; 95% CI, 0.22-3.62; P = .882) or length of stay (coeff 2.33, -8.23 to 12.90; P = .659) compared to CVG. Five-year survival was similar between both groups (PAR 59% vs CVG 69%; P = .153) and reoperation was negligible. Echocardiography revealed significantly lower aortic valve gradients in the PAR group (8.69 vs 15.45mm Hg; P < .0001), and smaller left ventricular dimensions both at 6-week and 1-year follow-up (P < .05).

CONCLUSIONS

This study highlights the comparable short- and midterm outcomes of PAR in cases of TAAD, in comparison to established therapy.

Phase-contrast magnetic resonance imaging and computational fluid dynamics assessment of thoracic aorta blood flow: a literature review

The death rate from thoracic aortic disease is on the rise and represents a growing global health concern as patients are often asymptomatic before acute events, which have devastating effects on health-related quality of life. Biomechanical factors have been found to play a major role in the development of both acquired and congenital aortic diseases. However, much is still unknown and translational benefits of this knowledge are yet to be seen. Phase-contrast cardiovascular magnetic resonance imaging of thoracic aortic blood flow has emerged as an exceptionally powerful non-invasive tool enabling visualization of complex flow patterns, and calculation of variables such as wall shear stress. This has led to multiple new findings in the areas of phenotype-dependent bicuspid valve flow patterns, thoracic aortic aneurysm formation and aortic prosthesis performance assessment. Phase-contrast cardiovascular magnetic resonance imaging has also been used in conjunction with computational fluid modelling techniques to produce even more sophisticated analyses, by allowing the calculation of haemodynamic variables with exceptional temporal and spatial resolution. Translationally, these technologies may potentially play a major role in the emergence of precision medicine and patient-specific treatments in patients with aortic disease. This clinically focused review will provide a systematic overview of key insights from published studies to date.

Is valve repair preferable to valve replacement in ischaemic mitral regurgitation? A systematic review and meta-analysis

Ischaemic mitral regurgitation (MR) is associated with poor survival. The favoured surgical option remains debatable. Our aim was to perform a meta-analysis to compare the outcomes of mitral valve repair (MVRp) with replacement (MVR). A literature search was conducted in PubMed, Medline and Ovid using the terms 'ischaemic mitral regurgitation', 'repair' and 'replacement'. The primary outcome measure was 30-day survival. The secondary outcome measures were MR recurrence and reoperation. Out of 310 articles, 18 fulfilled the inclusion criteria. A total of 3978 patients were included: 2563 (64%) MVRp cases and 1415 (36%) MVR cases. Operative techniques included annuloplasty for MVRp and subvalvular apparatus-sparing MVR techniques. Thirty-day mortality was lower after MVRp compared with MVR [OR 0.42; (95% CI 0.33-0.54; P = 0.0001)]. There was no difference in long-term survival ranging 1-5 years (HR 0.85, 95% CI 0.65-1.12). Recurrence of MR was significantly higher in the MVRp group (OR 4.26, 95% CI 2.52-7.22), as was the rate of reoperation (OR 2.03, 95% CI 1.49-2.77). Although MVR for ischaemic MR has a higher 30-day mortality rate compared with MVRp, MVRp is associated with the higher rate of MR recurrence and the need for reoperation. MVR remains an attractive option for ischaemic MR.