Effect of Transcatheter Aortic Valve Implantation vs Surgical Aortic Valve Replacement on All-Cause Mortality in Patients With Aortic Stenosis: A Randomized Clinical Trial.

Importance: Transcatheter aortic valve implantation (TAVI) is a less invasive alternative to surgical aortic valve replacement and is the treatment of choice for patients at high operative risk. The role of TAVI in patients at lower risk is unclear. Objective: To determine whether TAVI is noninferior to surgery in patients at moderately increased operative risk. Design, Setting, and Participants: In this randomized clinical trial conducted at 34 UK centers, 913 patients aged 70 years or older with severe, symptomatic aortic stenosis and moderately increased operative risk due to age or comorbidity were enrolled between April 2014 and April 2018 and followed up through April 2019. Interventions: TAVI using any valve with a CE mark (indicating conformity of the valve with all legal and safety requirements for sale throughout the European Economic Area) and any access route (n = 458) or surgical aortic valve replacement (surgery; n = 455). Main Outcomes and Measures: The primary outcome was all-cause mortality at 1 year. The primary hypothesis was that TAVI was noninferior to surgery, with a noninferiority margin of 5% for the upper limit of the 1-sided 97.5% CI for the absolute between-group difference in mortality. There were 36 secondary outcomes (30 reported herein), including duration of hospital stay, major bleeding events, vascular complications, conduction disturbance requiring pacemaker implantation, and aortic regurgitation. Results: Among 913 patients randomized (median age, 81 years [IQR, 78 to 84 years]; 424 [46%] were female; median Society of Thoracic Surgeons mortality risk score, 2.6% [IQR, 2.0% to 3.4%]), 912 (99.9%) completed follow-up and were included in the noninferiority analysis. At 1 year, there were 21 deaths (4.6%) in the TAVI group and 30 deaths (6.6%) in the surgery group, with an adjusted absolute risk difference of -2.0% (1-sided 97.5% CI, -∞ to 1.2%; P < .001 for noninferiority). Of 30 prespecified secondary outcomes reported herein, 24 showed no significant difference at 1 year. TAVI was associated with significantly shorter postprocedural hospitalization (median of 3 days [IQR, 2 to 5 days] vs 8 days [IQR, 6 to 13 days] in the surgery group). At 1 year, there were significantly fewer major bleeding events after TAVI compared with surgery (7.2% vs 20.2%, respectively; adjusted hazard ratio [HR], 0.33 [95% CI, 0.24 to 0.45]) but significantly more vascular complications (10.3% vs 2.4%; adjusted HR, 4.42 [95% CI, 2.54 to 7.71]), conduction disturbances requiring pacemaker implantation (14.2% vs 7.3%; adjusted HR, 2.05 [95% CI, 1.43 to 2.94]), and mild (38.3% vs 11.7%) or moderate (2.3% vs 0.6%) aortic regurgitation (adjusted odds ratio for mild, moderate, or severe [no instance of severe reported] aortic regurgitation combined vs none, 4.89 [95% CI, 3.08 to 7.75]). Conclusions and Relevance: Among patients aged 70 years or older with severe, symptomatic aortic stenosis and moderately increased operative risk, TAVI was noninferior to surgery with respect to all-cause mortality at 1 year. Trial Registration: isrctn.com Identifier: ISRCTN57819173.

Transradial Secondary Access to Guide Valve Implantation and Manage Peripheral Vascular Complications During Transcatheter Aortic Valve Implantation.

BACKGROUND: Vascular complications from transfemoral (TF) secondary access during transcatheter aortic valve implantation (TAVI) are common. We compare our experience of transradial (TR) versus transfemoral secondary access during TAVI and describe techniques for performing iliofemoral arterial intervention from the transradial approach. METHODS: All TAVI procedures with a single secondary access were included. Demographics, procedural details and 30-day outcomes were recorded. VARC-2 criteria were used for procedural complications. Procedures with TF primary access were stratified by the site of secondary arterial access. RESULTS: Single secondary access was used in 199 cases, of which 20 were performed via non-TF access. Of the 179 TF primary access cases, 115 (64%) used TR secondary access and 64 (36%) used TF secondary access. In the TR cohort percutaneous vascular intervention was performed from the transradial approach in 19 cases (17%). Emergent TF secondary access was not required in any case. There were no differences in procedural time, radiation dose, contrast use, bleeding complications, stroke or mortality between the groups. There was one secondary access complication in the TF cohort and none in the TR cohort. CONCLUSIONS: Transradial (TR) secondary access during TAVI is safe and feasible and may reduce the secondary access site vascular complication rate. With appropriate equipment, most peripheral vascular complications can be managed entirely via TR access avoiding unplanned femoral arterial access. TR secondary access should be considered the default approach for non-TF TAVI cases and can be considered for all TF cases as long as dedicated equipment is available.

Genetic variants associated with risk of atrial fibrillation regulate expression of PITX2, CAV1, MYOZ1, C9orf3 and FANCC.

Genome-wide association studies (GWAS) have identified genetic variants in a number of chromosomal regions that are associated with atrial fibrillation (AF). The mechanisms underlying these associations are unknown, but are likely to involve effects of the risk haplotypes on expression of neighbouring genes. To investigate the association between genetic variants at AF-associated loci and expression of nearby candidate genes in human atrial tissue and peripheral blood. Right atrial appendage (RAA) samples were collected from 122 patients undergoing cardiac surgery, of these, 12 patients also had left atrial appendage samples taken. 22 patients had a history of AF. Peripheral blood samples were collected from 405 patients undergoing diagnostic cardiac catheterisation. In order to tag genetic variation at each of nine loci, a total of 367 single nucleotide polymorphisms (SNPs) were genotyped using the Sequenom platform. Total expression of 16 candidate genes in the nine AF-associated regions was measured by quantitative PCR. The relative expression of each allele of the candidate genes was measured on the Sequenom platform using one or more transcribed SNPs to distinguish between alleles in heterozygotes. We tested association between the SNPs of interest and gene expression using total gene expression (integrating cis and trans acting sources of variation), and allelic expression ratios (specific for cis acting influences), in atrial tissue and peripheral blood. We adjusted for multiple comparisons using a Bonferroni approach. In subsidiary analyses, we compared the expression of candidate genes between patients with and without a history of AF. Total expression of 15 transcripts of 14 genes and allelic expression ratio of 14 transcripts of 14 genes in genomic regions associated with AF were measured in right atrial appendage tissue. 8 of these transcripts were also expressed in peripheral blood. Risk alleles at AF-associated SNPs were associated in cis with an increased expression of PITX2a (2.01-fold, p=6.5×10(-4)); and with decreased expression of MYOZ1 (0.39 fold; p=5.5×10(-15)), CAV1 (0.89 fold; p=5.9×10(-8)), C9orf3 (0.91 fold; 1.5×10(-5)), and FANCC (0.94-fold; p=8.9×10(-8)) in right atrial appendage. Of these five genes, only CAV1 was expressed in peripheral blood; association between the same AF risk alleles and lower expression of CAV1 was confirmed (0.91 fold decrease; p=4.2×10(-5)). A history of AF was also associated with a decrease in expression of CAV1 in both right and left atria (0.84 and 0.85 fold, respectively; p=0.03), congruent with the magnitude of the effect of the risk SNP on expression, and independent of genotype. The analyses in peripheral blood showed association between AF risk SNPs and decreased expression of KCNN3 (0.85-fold; p=2.1×10(-4)); and increased expression of SYNE2 (1.12-fold; p=7.5×10(-24)); however, these associations were not detectable in atrial tissue. We identified novel cis-acting associations in atrial tissue between AF risk SNPs and increased expression of PITX2a/b; and decreased expression of CAV1 (an association also seen in peripheral blood), C9orf3 and FANCC. We also confirmed a previously described association between AF risk variants and MYOZ1 expression. Analyses of peripheral blood illustrated tissue-specificity of cardiac eQTLs and highlight the need for larger-scale genome-wide eQTL studies in cardiac tissue. Our results suggest novel aetiological roles for genes in four AF-associated genomic regions.

Chromosome 16q22 variants in a region associated with cardiovascular phenotypes correlate with ZFHX3 expression in a transcript-specific manner.

BACKGROUND: The ZFHX3 gene, located in Chromosome 16q22.3, codes for a transcription factor which is widely expressed in human tissues. Genome-wide studies have identified associations between variants within the gene and Kawasaki disease and atrial fibrillation. ZFHX3 has two main transcripts that utilise different transcription start sites. We examined the association between genetic variants in the 16q22.3 region and expression of ZFHX3 to identify variants that regulate gene expression. RESULTS: We genotyped 65 single-nucleotide polymorphisms to tag genetic variation at the ZFHX3 locus in two cohorts, 451 British individuals recruited in the North East of England and 310 mixed-ancestry individuals recruited in South Africa. Allelic expression analysis revealed that the minor (A) allele of rs8060701, a variant in the first intron of ZFHX3, was associated with a 1.16-fold decrease in allelic expression of both transcripts together, (p = 4.87e-06). The minor (C) allele of a transcribed variant, rs10852515, in the second exon of ZFHX3 isoform A was independently associated with a 1.36-fold decrease in allelic expression of ZFHX3 A (p = 7.06e-31), but not overall ZFHX3 expression. However, analysis of total gene expression of ZFHX3 failed to detect an association with genotype at any variant. Differences in linkage disequilibrium between the two populations allowed fine-mapping of the locus to a 7 kb region overlapping exon 2 of ZFHX3 A. We did not find any association between ZFHX3 expression and any of the variants identified by genome wide association studies. CONCLUSIONS: ZFHX3 transcription is regulated in a transcript-specific fashion by independent cis-acting transcribed polymorphisms. Our results demonstrate the power of allelic expression analysis and trans-ethnic fine mapping to identify transcript-specific cis-acting regulatory elements.

The impact of ageing on the health and wellbeing of people with thalidomide embryopathy: a comparison of the health impact with the general population.

PURPOSE: As people living with thalidomide embryopathy (TE) are now entering their seventh decade, we examine the impact of ageing and the prevalence of comorbid health conditions reported in holistic needs assessments (HNAs) by individuals with TE, compare it with an age-matched sample of the general population, and explore the relationship between comorbidities and TE pattern of impairment. MATERIALS AND METHODS: The HNA categories were mapped and compared to those of the Health Survey for England (HSE) and analysed across four impairment groups (A-D). RESULTS: 94% (392/415) of individuals with TE residing in the UK participated in the HNA and consented to a secondary analysis of the data. Less than 2% (5/392) reported no comorbidities; 94% reported nervous system problems; including pain, pins and needles and numbness. Individuals with TE reported a significantly greater number of health comorbidities, including musculoskeletal problems, than the age-matched HSE population. CONCLUSIONS: Individuals with TE report significantly more health and well-being concerns than the general population of a similar age. Long-term monitoring is needed to ensure that support and rehabilitation services can meet their evolving needs.

People living with thalidomide's teratogenic effects are now entering their seventh decade.As they age, these individuals experience the long-term consequences linked to over-use of certain joints, including musculoskeletal and neuropathic pain.An understanding of the lived experience of TE with increasing age has the potential to inform the planning and provision of adequate and appropriate rehabilitation services moving forward.Adoption of a holistic approach to rehabilitation could help people living with TE to maintain functional independence as they enter their seventh decade.

Telomerase expression in the mammalian heart.

While the mammalian heart has low, but functionally significant, levels of telomerase expression, the cellular population responsible remains incompletely characterized. This study aimed to identify the cell types responsible for cardiac telomerase activity in neonatal, adult, and cryoinjured adult hearts using transgenic mice expressing green fluorescent protein (GFP), driven by the promoter for murine telomerase reverse transcriptase (mTert), which is a necessary and rate-limiting component of telomerase. A rare population of mTert-GFP-expressing cells was identified that possessed all detectable cardiac telomerase RNA and telomerase activity. It was heterogeneous and included cells coexpressing markers of cardiomyocytic, endothelial, and mesenchymal lineages, putative cardiac stem cell markers, and, interestingly, cardiomyocytes with a differentiated phenotype. Quantification using both flow cytometry and immunofluorescence identified a significant decline in mTert-GFP cells in adult animals compared to neonates (∼9- and ∼20-fold, respectively). Cardiac injury resulted in a ∼6.45-fold expansion of this population (P<0.005) compared with sham-operated controls. This study identifies the cells responsible for cardiac telomerase activity, demonstrates a significant diminution with age but a marked response to injury, and, given the relationship between telomerase activity and stem cell populations, suggests that they represent a potential target for further investigation of cardiac regenerative potential.

Senescent cardiomyocytes contribute to cardiac dysfunction following myocardial infarction.

Myocardial infarction is a leading cause of morbidity and mortality. While reperfusion is now standard therapy, pathological remodelling leading to heart failure remains a clinical problem. Cellular senescence has been shown to contribute to disease pathophysiology and treatment with the senolytic navitoclax attenuates inflammation, reduces adverse myocardial remodelling and results in improved functional recovery. However, it remains unclear which senescent cell populations contribute to these processes. To identify whether senescent cardiomyocytes contribute to disease pathophysiology post-myocardial infarction, we established a transgenic model in which p16 (CDKN2A) expression was specifically knocked-out in the cardiomyocyte population. Following myocardial infarction, mice lacking cardiomyocyte p16 expression demonstrated no difference in cardiomyocyte hypertrophy but exhibited improved cardiac function and significantly reduced scar size in comparison to control animals. This data demonstrates that senescent cardiomyocytes participate in pathological myocardial remodelling. Importantly, inhibition of cardiomyocyte senescence led to reduced senescence-associated inflammation and decreased senescence-associated markers within other myocardial lineages, consistent with the hypothesis that cardiomyocytes promote pathological remodelling by spreading senescence to other cell-types. Collectively this study presents the demonstration that senescent cardiomyocytes are major contributors to myocardial remodelling and dysfunction following a myocardial infarction. Therefore, to maximise the potential for clinical translation, it is important to further understand the mechanisms underlying cardiomyocyte senescence and how to optimise senolytic strategies to target this cell lineage.

Cardiac Mesenchymal Stem Cell-like Cells Derived from a Young Patient with Bicuspid Aortic Valve Disease Have a Prematurely Aged Phenotype.

There is significant interest in the role of stem cells in cardiac regeneration, and yet little is known about how cardiac disease progression affects native cardiac stem cells in the human heart. In this brief report, cardiac mesenchymal stem cell-like cells (CMSCLC) from the right atria of a 21-year-old female patient with a bicuspid aortic valve and aortic stenosis (referred to as biscuspid aortic valve disease BAVD-CMSCLC), were compared with those of a 78-year-old female patient undergoing coronary artery bypass surgery (referred to as coronary artery disease CAD-CMSCLC). Cells were analyzed for expression of MSC markers, ability to form CFU-Fs, metabolic activity, cell cycle kinetics, expression of NANOG and p16, and telomere length. The cardiac-derived cells expressed MSC markers and were able to form CFU-Fs, with higher rate of formation in CAD-CMSCLCs. BAVD-CMSCLCs did not display normal MSC morphology, had a much lower cell doubling rate, and were less metabolically active than CAD-CMSCLCs. Cell cycle analysis revealed a population of BAVD-CMSCLC in G2/M phase, whereas the bulk of CAD-CMSCLC were in the G0/G1 phase. BAVD-CMSCLC had lower expression of NANOG and shorter telomere lengths, but higher expression of p16 compared with the CAD-CMSCLC. In conclusion, BAVD-CMSCLC have a prematurely aged phenotype compared with CAD-CMSCLC, despite originating from a younger patient.

Long-term outcomes of mini-sternotomy versus conventional sternotomy for aortic valve replacement: a randomized controlled trial.

OBJECTIVES: Aortic valve replacement (AVR) for severe symptomatic aortic stenosis is one of the most common cardiac surgical procedures with excellent long-term outcomes. Multiple previous studies have compared short-term outcomes of AVR with mini-sternotomy versus AVR with conventional sternotomy. We have previously reported the results of the randomized MAVRIC trial, which aimed to evaluate early postoperative morbidity among patients undergoing mini-sternotomy and conventional sternotomy AVR. We now report the long-term all-cause mortality, reoperation, MACE outcomes and echocardiographic data from this trial. METHODS: The prospective, randomized, single-centre, single-blind MAVRIC (manubrium-limited mini-sternotomy versus conventional sternotomy for aortic valve replacement) trial compared manubrium-limited mini-sternotomy and conventional median sternotomy for the treatment of patients with severe aortic stenosis. The previously reported primary outcome was the proportion of patients receiving red cell transfusion postoperatively and within 7 days of the index procedure. Currently reported exploratory analyses of a combined long-term all-cause mortality and reoperation were compared between groups via the log-rank test. Sensitivity analyses reviewed individual components of the combined end point. The primary analysis and long-term exploratory analyses were based on an intention-to-treat principle. RESULTS: Between March 2014 and June 2016, 270 patients were enrolled and randomized in a 1:1 fashion to undergo mini-sternotomy AVR (n = 135) or conventional median sternotomy AVR (n = 135). At the median follow-up of 6.1 years, the composite outcome of all-cause mortality and reoperation occurred in 18.5% (25/135) of patients in the conventional sternotomy group and in 17% (23/135) of patients in the mini-sternotomy group. The incidence of chronic kidney disease, cerebrovascular accident and myocardial infarction was not significantly different between 2 groups. Follow-up echocardiographic data suggested no difference in peak and mean gradients or incidence of aortic regurgitation between 2 approaches. CONCLUSIONS: This exploratory long-term analysis demonstrated that, in patients with severe aortic stenosis undergoing isolated AVR, there was no significant difference between manubrium-limited mini-sternotomy and conventional sternotomy with respect to all-cause mortality, rate of reoperation, MACE events and echocardiographic data at the median of 6.1-year follow-up.

Senescence and senolytics in cardiovascular disease: Promise and potential pitfalls.

Ageing is the biggest risk factor for impaired cardiovascular health, with cardiovascular disease being the cause of death in 40 % of individuals over 65 years old. Ageing is associated with an increased prevalence of atherosclerosis, coronary artery stenosis and subsequent myocardial infarction, thoracic aortic aneurysm, valvular heart disease and heart failure. An accumulation of senescence and increased inflammation, caused by the senescence-associated secretory phenotype, have been implicated in the aetiology and progression of these age-associated diseases. Recently it has been demonstrated that compounds targeting components of anti-apoptotic pathways expressed by senescent cells can preferentially induce senescence cells to apoptosis and have been termed senolytics. In this review, we discuss the evidence demonstrating that senescence contributes to cardiovascular disease, with a particular focus on studies that indicate the promise of senotherapy. Based on these data we suggest novel indications for senolytics as a treatment of cardiovascular diseases which have yet to be studied in the context of senotherapy. Finally, while the potential benefits are encouraging, several complications may result from senolytic treatment. We, therefore, consider these challenges in the context of the cardiovascular system.

Mini-sternotomy versus conventional sternotomy for aortic valve replacement: a randomised controlled trial.

OBJECTIVE: To compare clinical and health economic outcomes after manubrium-limited mini-sternotomy (intervention) and conventional median sternotomy (usual care). DESIGN: A single-blind, randomised controlled trial. SETTING: Single centre UK National Health Service tertiary hospital. PARTICIPANTS: Adult patients undergoing aortic valve replacement (AVR) surgery. INTERVENTIONS: Intervention was manubrium-limited mini-sternotomy performed using a 5-7 cm midline incision. Usual care was median sternotomy performed using a midline incision from the sternal notch to the xiphisternum. PRIMARY AND SECONDARY OUTCOME MEASURES: The primary outcome was the proportion of patients who received a red cell transfusion postoperatively and within 7 days of index surgery. Secondary outcomes included proportion of patients receiving a non-red cell blood component transfusion and number of units transfused within 7 days and during index hospital stay, quality of life and cost-effectiveness analyses. RESULTS: 270 patients were randomised, received surgery and contributed to the intention to treat analysis. No difference between mini and conventional sternotomy in red-cell transfusion within 7 days was found; 23/135 patients in each arm received a transfusion, OR 1.0 (95% CI 0.5 to 2.0) and risk difference 0.0 (95% CI -0.1 to 0.1). Mini-sternotomy reduced chest drain losses (mean 181.6 mL (SD 138.7) vs conventional, mean 306·9 mL (SD 348.6)); this did not reduce red-cell transfusions. Mean valve size and postoperative valve function were comparable between mini-sternotomy and conventional groups; 23 mm vs 24 mm and 6/134 moderate or severe aortic regurgitation vs 3/130, respectively. Mini-sternotomy resulted in longer bypass (82.7 min (SD 23.5) vs 59.6 min (SD 15.1)) and cross-clamp times (64.1 min (SD 17.1) vs 46·3 min (SD 10.7)). Conventional sternotomy was more cost-effective with only a 5.8% probability of mini-sternotomy being cost-effective at a willingness to pay of £20 000/QALY (Quality Adjusted Life Years). CONCLUSIONS: AVR via mini-sternotomy did not reduce red blood cell transfusion within 7 days following surgery when compared with conventional sternotomy. TRIAL REGISTRATION NUMBER: ISRCTN29567910; Results.

Human Cardiac-Mesenchymal Stem Cell-Like Cells, a Novel Cell Population with Therapeutic Potential.

Cardiac stem/progenitors are being used in the clinic to treat patients with a range of cardiac pathologies. However, improvements in heart function following treatment have been reported to be variable, with some showing no response. This discrepancy in response remains unresolved. Mesenchymal stem cells (MSCs) have been highlighted as a regenerative tool as these cells display both immunomodulatory and proregenerative activities. The purpose of this study was to derive a cardiac MSC population to provide an alternative/support to current therapies. We derived human cardiac-mesenchymal stem cell-like cells (CMSCLC), so named as they share some MSC characteristics. However, CMSCLC lack the MSC trilineage differentiation capacity, being capable of only rare adipogenic differentiation and demonstrating low/no osteogenic or chondrogenic potential, a phenotype that may have advantages following transplantation. Furthermore, CMSCLC expressed low levels of p16, high levels of MHCI, and low levels of MHCII. A lack of senescent cells would also be advantageous for cells to be used therapeutically, as would the ability to modulate the immune response. Crucially, CMSCLC display a transcriptional profile that includes genes associated with cardioprotective/cardiobeneficial effects. CMSCLC are also secretory and multipotent, giving rise to cardiomyocytes and endothelial cells. Our findings support CMSCLC as a novel cell population suitable for use for transplantation.

Manubrium-limited ministernotomy versus conventional sternotomy for aortic valve replacement (MAVRIC): study protocol for a randomised controlled trial.

BACKGROUND: Aortic valve replacement is one of the most common cardiac surgical procedures performed worldwide. Conventional aortic valve replacement surgery is performed via a median sternotomy; the sternum is divided completely from the sternal notch to the xiphisternum. Minimally invasive aortic valve replacement, using a new technique called manubrium-limited ministernotomy, divides only the manubrium from the sternal notch to 1 cm below the manubrio-sternal junction. More than one third of patients undergoing conventional sternotomy develop clinically significant bleeding requiring post-operative red blood cell transfusion. Case series data suggest a potentially clinically significant difference in red blood cell transfusion requirements between the two techniques. Given the implications for National Health Service resources and patient outcomes, a definitive trial is needed. METHODS/DESIGN: This is a single-centre, single-blind, randomised controlled trial comparing aortic valve replacement surgery using manubrium-limited ministernotomy (intervention) and conventional median sternotomy (usual care). Two hundred and seventy patients will be randomised in a 1:1 ratio between the intervention and control arms, stratified by baseline logistic EuroSCORE and haemoglobin value. Patients will be followed for 12 weeks from discharge following their index operation. The primary outcome is the proportion of patients who receive a red blood cell transfusion post-operatively within 7 days of surgery. Secondary outcomes include red blood cell and blood product transfusions, blood loss, re-operation rates, sternal wound pain, quality of life, markers of inflammatory response, hospital discharge, health care utilisation, cost and cost effectiveness and adverse events. DISCUSSION: This is the first trial to examine aortic valve replacement via manubrium-limited ministernotomy versus conventional sternotomy when comparing red blood cell transfusion rates following surgery. Surgical trials present significant challenges; strengths of this trial include a rigorous research design, standardised surgery performed by experienced consultant cardiothoracic surgeons, an agreed anaesthetic regimen, patient blinding and consultant-led patient recruitment. The MAVRIC trial will demonstrate that complex surgical trials can be delivered to exemplary standards and provide the community with the knowledge required to inform future care for patients requiring aortic valve replacement surgery. TRIAL REGISTRATION: International Standard Randomised Controlled Trial Number (ISRCTN) ISRCTN29567910 . Registered on 3 February 2014.

Manubrium-limited sternotomy decreases blood loss after aortic valve replacement surgery.

OBJECTIVES: Minimally invasive surgical approaches for aortic valve replacement (AVR) are growing in popularity in an attempt to decrease morbidity from conventional surgery. We have adopted a technique that divides only the manubrium and spares the body of the sternum. We sought to determine whether patients benefit from this less-invasive approach. METHODS: We retrospectively analysed our prospectively maintained database to review all isolated aortic valve replacements performed in an 18-month period from November 2011 to April 2013. RESULTS: One hundred and ninety-one patients were identified, 98 underwent manubrium-limited sternotomy (Mini-AVR) and 93 had a conventional median sternotomy (AVR). The two groups were well matched for preoperative variables and risk (mean logistic EuroSCORE mini-AVR 7.15 vs AVR 6.55, P = 0.47). Mean cardiopulmonary bypass and aortic cross-clamp times were 10 and 6 min longer, respectively, in the mini-AVR group (mean values 88 vs 78 min, P = 0.00040, and 66 vs 60 min, P = 0.0078, respectively). Mini-AVR patients had significantly less postoperative blood loss, 332 vs 513 ml, P = 0.00021, and were less likely to require blood products (fresh-frozen plasma and platelets), 24 vs 36%, P = 0.042. Postoperative complications and length of stay were similar (discharge on or before Day 4; mini-AVR 15 vs AVR 8%, P = 0.17). Valve outcome (paravalvular leak mini-AVR 2 vs AVR 1%, P = 1.00) and survival (mini-AVR 99 vs AVR 97%, P = 0.36) were equal. CONCLUSIONS: A manubrium-limited approach maintains outcomes achieved for aortic valve replacement by conventional sternotomy while significantly reducing postoperative blood loss and transfusion of blood products.

Optimised protocols for the identification of the murine cardiac side population.

Cardiac side population (CSP) cells, defined by their ability to efflux the vital dye Hoechst 33342, have been identified as putative cardiac stem cells based on their potential to give rise to both cardiomyocytes and endothelial cells. The CSP phenotype relies on an active metabolic pathway and cell viability to identify a rare population of cells and therefore technical differences in the CSP staining protocol can lead to inconsistent results and discrepancies between studies. Here we describe an established protocol for CSP identification and have optimised a protocol for CSP analysis utilizing an automated cardiac digestion procedure using gentleMACs dissociation and Hoechst 33342 staining followed by dual wavelength flow cytometric analysis.

Video-assisted thoracoscopic left ventricular pacing in patients with and without previous sternotomy.

BACKGROUND: Left ventricular epicardial lead placement via video-assisted thoracoscopy (VAT) is a recognized surgical technique to achieve cardiac resynchronization therapy (CRT) when conventional lead placement has failed. Its role in patients with previous sternotomy is uncertain. We describe our experience in a cohort of patients including those with previous sternotomy. METHODS: This was a retrospective review of consecutive patients undergoing VAT lead implantation for CRT in a single center between 2004 and 2011. All patients fulfilled conventional criteria for CRT and were followed up at 4 to 6 weeks and then at 3-month intervals. Clinical and pacing parameters were compared at baseline and at the latest review. RESULTS: Thirty-two patients (27 men; mean age, 67 ± 9 years) underwent VAT left ventricular lead implantation. Mean follow-up duration was 704 ± 450 days. Ten patients (31%) had undergone previous sternotomy. Thoracoscopic lead implantation was successful in 31 patients (97%): 1 patient with two previous sternotomies required conversion to open thoracotomy due to bleeding with multiple adhesions. Satisfactory implantation pacing thresholds of 2 volts or less at 0.5 ms were achieved in all patients. Despite a longer operative time in those with previous sternotomy, all clinical and pacing outcomes, including complications, clinical response to CRT, and long-term pacing variables were similar between the groups. CONCLUSIONS: VAT left ventricular lead placement appears safe and effective in selected patients with previous sternotomy, including coronary artery bypass operations, with postoperative outcomes comparable with those patients without previous sternotomy.

Aneurysmal dilation of the ascending thoracic aorta and the aortic arch following surgical repair of type A dissection.

This report describes the case of a 71-year-old lady who was diagnosed with a Stanford type A dissecting aortic aneurysm which resulted in paraplegia secondary to spinal artery injury at T12 level. She had surgical repair with a tube graft. At a routine review CT scan 2 years postdissection, she presents with asymptomatic but significant dilation, of maximum diameter 78 mm, of the superior part of the ascending thoracic aorta, extending into the arch, suggestive of false aneurysm formation at the surgical anastomoses. There was also thrombosis of the false lumen in the distal arch and descending thoracic aorta. She is a candidate for urgent resection of the aortic arch and reimplantation of the brachiocephalic vessels.

Dermal stem cells can differentiate down an endothelial lineage.

In this study, we have demonstrated that cells of neural crest origin located in the dermal papilla (DP) exhibit endothelial marker expression and a functional activity. When grown in endothelial growth media, DP primary cultures upregulate expression of vascular endothelial growth factor receptor 1 (FLT1) mRNA and downregulate expression of the dermal stem cell marker α-smooth muscle actin. DP cells have demonstrated functional characteristics of endothelial cells, including the ability to form capillary-like structures on Matrigel, increase uptake of low-density lipoprotein and upregulate ICAM1 (CD54) in response to tumour necrosis factor alpha (TNF-α) stimulation. We confirmed that these observations were not due to contaminating endothelial cells, by using DP clones. We have also used the WNT1cre/ROSA26R and WNT1cre/YFP lineage-tracing mouse models to identify a population of neural crest-derived cells in DP cultures that express the endothelial marker PECAM (CD31); these cells also form capillary-like structures on Matrigel. Importantly, cells of neural crest origin that express markers of endothelial and mesenchymal lineages exist within the dermal sheath of the vibrissae follicle.