Conventional versus minimally invasive extra-corporeal circulation in patients undergoing cardiac surgery: A randomized controlled trial (COMICS).

INTRODUCTION: The trial hypothesized that minimally invasive extra-corporeal circulation (MiECC) reduces the risk of serious adverse events (SAEs) after cardiac surgery operations requiring extra-corporeal circulation without circulatory arrest. METHODS: This is a multicentre, international randomized controlled trial across fourteen cardiac surgery centres including patients aged ≥18 and <85 years undergoing elective or urgent isolated coronary artery bypass grafting (CABG), isolated aortic valve replacement (AVR) surgery, or CABG + AVR surgery. Participants were randomized to MiECC or conventional extra-corporeal circulation (CECC), stratified by centre and operation. The primary outcome was a composite of 12 post-operative SAEs up to 30 days after surgery, the risk of which MiECC was hypothesized to reduce. Secondary outcomes comprised: other SAEs; all-cause mortality; transfusion of blood products; time to discharge from intensive care and hospital; health-related quality-of-life. Analyses were performed on a modified intention-to-treat basis. RESULTS: The trial terminated early due to the COVID-19 pandemic; 1071 participants (896 isolated CABG, 97 isolated AVR, 69 CABG + AVR) with median age 66 years and median EuroSCORE II 1.24 were randomized (535 to MiECC, 536 to CECC). Twenty-six participants withdrew after randomization, 22 before and four after intervention. Fifty of 517 (9.7%) randomized to MiECC and 69/522 (13.2%) randomized to CECC group experienced the primary outcome (risk ratio = 0.732, 95% confidence interval (95% CI) = 0.556 to 0.962, p = 0.025). The risk of any SAE not contributing to the primary outcome was similarly reduced (risk ratio = 0.791, 95% CI 0.530 to 1.179, p = 0.250). CONCLUSIONS: MiECC reduces the relative risk of primary outcome events by about 25%. The risk of other SAEs was similarly reduced. Because the trial terminated early without achieving the target sample size, these potential benefits of MiECC are uncertain.

Incidence and outcomes of surgical pulmonary embolectomy in the UK.

BACKGROUND: Surgical pulmonary embolectomy is rarely used for the treatment of massive acute pulmonary embolism. The aim of this study was to assess the incidence and outcomes of this operation by undertaking a retrospective analysis of a large national registry in the UK. METHODS: All acute pulmonary embolectomies performed between 1996 and 2018 were captured in the National Institute of Cardiovascular Outcomes Research central database. Trends in the number of operations performed during this interval and reported in-hospital outcomes were analysed retrospectively. Multivariable logistic regression was used to identify independent risk factors for in-hospital death. RESULTS: All 256 patients treated surgically for acute pulmonary embolism during the study interval were included in the analysis. Median age at presentation was 54 years, 55.9% of the patients were men, 48.0% had class IV heart failure symptoms, and 37.5% had preoperative cardiogenic shock. The median duration of bypass was 73 min, and median cross-clamp time was 19 min. Cardioplegic arrest was used in 53.1% of patients. The median duration of hospital stay was 11 days. The in-hospital mortality rate was 25%, postoperative stroke occurred in 5.4%, postoperative dialysis was required in 16%, and the reoperation rate for bleeding was 7.5%. Risk-adjusted multivariable analysis revealed cardiogenic shock (OR 2.54, 95% c.i. 1.05 to 6.21; P = 0.038), preoperative ventilation (OR 5.85, 2.22 to 16.35; P < 0.001), and duration of cardiopulmonary bypass exceeding 89 min (OR 7.82, 3.25 to 20.42; P < 0.001) as significant independent risk factors for in-hospital death. CONCLUSION: Surgical pulmonary embolectomy is rarely performed in the UK, and is associated with significant mortality and morbidity. Preoperative ventilation, cardiogenic shock, and increased duration of bypass were significant predictors of in-hospital death.

A blood clot in the lung can prevent the lungs from working properly and put pressure on the heart to work harder. Small clots can be treated with medications taken at home and are not a danger to life. Larger blood clots can put a lot of pressure on the heart and need immediate hospital treatment. Large blood clots can be treated with 'clot busting' medications, the delivery of a small tube into the blood vessels of the lung to suck up the clot or deliver medications directly on to its surface, and finally a form of open-heart surgery. With this surgery, a surgeon opens the chest, make a cut into the large vessels containing the clot, and physically removes the large piece of obstructing clot. The aim of this study was to describe and analyse the outcomes of this operation done in the UK over a long period. A database was used to find out how often and where this operation took place and its results. The available data were studied to try to understand how helpful this operation is to patients with lung blood clots. Between 1996 and 2018, 256 people had this operation. One in four patients did not survive the operation, 5.4% developed a clot or bleed in the brain, 16% needed to go on to a dialysis machine, and 7.5% had to be rushed back into theatre because of bleeding. Needing a ventilator machine for help with breathing, being in a sudden state of heart failure, and a long time on the heart bypass machine were all linked with patients who did not survive. This operation is rarely performed in the UK, and is often linked to a high chance of death or serious complication. In this study, the points described above were linked to a bad outcome.

Validation of the German Registry for Acute Aortic Dissection Type A Score in predicting 30-day mortality after type A aortic dissection surgery.

OBJECTIVES: No reliable scores are available to predict mortality following surgery for type A acute aortic dissection (TAAAD). Recently, the German Registry of Acute Aortic Dissection Type A (GERAADA) score has been developed. We aim to compare how the GERAADA score performs in predicting operative mortality for TAAAD to the European System for Cardiac Operative Risk Evaluation (EuroSCORE) II. METHODS: We calculated the GERAADA score and EuroSCORE II in patients who underwent TAAAD repair at the Bristol Heart Institute. As there are no precise criteria to calculate the GERAADA score, we used 2 methods: a Clinical-GERAADA score, which evaluated malperfusion with clinical and radiological evidence, and a Radiological-GERAADA score, where malperfusion was assessed by computed tomography scan alone. RESULTS: 207 consecutive patients had surgery for TAAAD, and the observed 30-day mortality was 15%. The Clinical-GERAADA score showed the strongest discriminative power with an area under the curve (AUC) of 0.80 [95% confidence interval (CI) 0.71-0.89], while the Radiological-GERAADA score had an AUC of 0.77 (95% CI 0.67-0.87). EuroSCORE II showed acceptable discriminative power with an AUC of 0.77 (95% CI 0.67-0.87). CONCLUSIONS: Clinical GERAADA score performed better than the other scores and it is specific and easy to use in the context of a TAAAD. Further validation of the new criteria for malperfusion is needed.

Propensity matched analysis of minimally invasive versus conventional isolated aortic valve replacement.

OBJECTIVE: To analyse the early and mid-term outcome of patients undergoing conventional aortic valve replacement (AVR) versus minimally invasive via hemi-sternotomy aortic valve replacement (MIAVR). METHODS: A single centre retrospective study involving 653 patients who underwent isolated aortic valve replacement (AVR) either via conventional AVR (n = 516) or MIAVR (n = 137) between August 2015 and March 2020. Using pre-operative characteristics, patients were propensity matched (PM) to produce 114 matched pairs. Assessment of peri-operative outcomes, early and mid-term survival and echocardiographic parameters was performed. RESULTS: The mean age of the PM conventional AVR group was 71.5 (±8.9) years and the number of male (n = 57) and female (n = 57) patients were equal. PM MIAVR group mean age was 71.1 (±9.5) years, and 47% of patients were female (n = 54) and 53% male (n = 60). Median follow-up for PM conventional AVR and MIAVR patients was 3.4 years (minimum 0, maximum 4.8 years) and 3.4 years (minimum 0, maximum 4.8 years), respectively. Larger sized aortic valve prostheses were inserted in the MIAVR group (median 23, IQR = 4) versus conventional AVR group (median 21, IQR = 2; p = 0.02, SMD = 0.34). Cardiopulmonary bypass (CPB) time was longer with MIAVR (94.4 ± 19.5 minutes) compared to conventional AVR (83.1 ± 33.3; p = 0.0001, SMD = 0.41). Aortic cross-clamp (AoX) time was also longer in MIAVR (71.6 ± 16.5 minutes) compared to conventional AVR (65.0 ± 52.8; p = 0.0001, SMD = 0.17). There were no differences in the early post-operative complications and mortality between the two groups. Follow-up echocardiographic data showed significant difference in mean aortic valve gradients between conventional AVR and MIAVR groups (17.3 ± 8.2 mmHg vs 13.0 ± 5.1 mmHg, respectively; p = 0.01, SMD = -0.65). There was no significant difference between conventional AVR and MIAVR in mid-term survival at 3 years (88.6% vs 92.1%; log-rank test p = 0.31). CONCLUSION: Despite the longer CPB and AoX times in the MIAVR group, there was no significant difference in early complications, mortality and mid-term survival between MIAVR and conventional AVR.

In-hospital outcomes predictors and trends of redo sternotomy aortic root replacements: insights from a UK registry analysis.

Background: Redo sternotomy aortic root surgery is technically demanding, and the evidence on outcomes is mostly from retrospective, small sample, single-centre studies. We report the trend, early clinical results and outcome predictors of redo aortic root replacement over 20 years in the United Kingdom. Methods: We retrospectively analysed collected data from the UK National Adult Cardiac Surgery Audit (NACSA) on all redo sternotomy aortic root replacements performed between 30th January 1998 and 19th March 2019. We analysed trends in the volume of operations, characteristics of hospital survivors vs. non-survivors, and predictors of in-hospital outcomes. Results: During the study period, 1,107 redo sternotomy aortic root replacements were performed (median age 59, 26% of patients were females). Eighty-four per cent of cases (N = 931) underwent a composite root replacement, 11% (N = 119) had homograft root replacement and valve-sparing root replacement was performed in 5.1% (N = 57) of cases. There was a steady increase in the volume of redo sternotomy root replacements beyond 2006, from an annual volume of 22 procedures in 2006 to 106 procedures in 2017. Hospital mortality was 17% (n = 192), postoperative stroke or TIA occurred in 5.2% (n = 58), and postoperative dialysis was required in 11% (n = 109) of patients. Return to the theatre for bleeding/tamponade was required in 9% (n = 102) and median in-hospital stay was 9 days. Age >59 (OR: 2.99, CI: 1.92-4.65, P < 0.001), recent myocardial infarction (OR: 6.42, CI: 2.24-18.41, P = 0.001) were associated with increased in-hospital mortality. Emergency surgery (OR: 3.95, 2.27-6.86, P < 0.001), surgery for endocarditis (OR: 2.05, CI: 1.26-3.33, P = 0.001), salvage coronary artery bypass grafting (OR: 2.20, CI: 1.37-3.54, P < 0.001), arch surgery (OR: 2.47, CI: 1.30-3.61, P = 0.018) and aortic cross-clamp longer than 169 min (OR: 2.17, CI: 1.00-1.01, P = 0.003) were associated with increased risk of mortality. We found no effect of the centre or surgeon volume on mortality (P > 0.05). Conclusions: Redo sternotomy aortic root replacement still carries significant morbidity and mortality and is sporadically performed across surgeons and centres in the UK.

Surgical outcomes and optimal approach to treatment of aortic valve endocarditis with aortic root abscess.

OBJECTIVES: To evaluate the impact of aortic root abscess (ARA) on the postoperative outcomes of surgically managed infective endocarditis (IE) and to inform optimal surgical approach. METHODS: Between 2009 and 2020, 143 consecutive patients who underwent surgical management for aortic-valve IE were included in a retrospective cohort study. Multivariable and propensity-weighted analyses were used to adjust for demographic imbalances between those without (n = 93; NARA) and with an ARA (n = 50). Additionally, empirical subgroup analysis appraised the two most used surgical techniques; patch reconstruction (PR) and aortic root replacement (ARR). RESULTS: Demographic characteristics were similar between ARA and NARA except for logistic EuroSCORE, previous valve surgery, and multivalvular infection. In-hospital mortality was 8% and 12% in NARA and ARA, respectively (p = .38), with mortality rates consistently nonsignificantly higher in ARA across all time periods. The overall reoperation rate was also higher in ARA (27% vs. 14%; p = .09) and ARA was shown to be associated with late reoperation (odds ratio [OR] = 2.74; 95% confidence interval [CI] = 1.18-6.36). Patients treated with an ARR showed a 16% increase in late mortality when compared with PR (40% vs. 24%; p = .27) and a 17% lower reoperation rate (14% vs. 31%; p = .24). Propensity-weighted analysis identified ARR as a significant protective factor for reoperation (hazard ratio = 0.05; 95% CI = 0.01-0.34). CONCLUSIONS: The presence of an ARA in aortic valve endocarditis was not associated with significantly higher early and late mortality but is linked with a higher reoperation rate at our institution. ARR in ARA is protective from reoperation so should be considered best practice in this setting.

Effects of the harvesting technique and external stenting on progression of vein graft disease 2 years after coronary artery bypass.

OBJECTIVES: In a post hoc analysis of the VEST III trial, we investigated the effect of the harvesting technique on saphenous vein graft (SVG) patency and disease progression after coronary artery bypass grafting. METHODS: Angiographic outcomes were assessed in 183 patients undergoing open (126 patients, 252 SVG) or endoscopic harvesting (57 patients, 114 SVG). Overall SVG patency was assessed by computed tomography angiography at 6 months and by coronary angiography at 2 years. Fitzgibbon patency (FP I, II and III) and intimal hyperplasia (IH) in a patient subset were assessed by coronary angiography and intravascular ultrasound, respectively, at 2 years. RESULTS: Baseline characteristics were similar between patients who underwent open and those who underwent endoscopic harvesting. Open compared with endoscopic harvesting was associated with higher overall SVG patency rates at 6 months (92.9% vs 80.4%, P = 0.04) and 2 years (90.8% vs 73.9%, P = 0.01), improved FP I, II and III rates (65.2% vs 49.2%; 25.3% vs 45.9%, and 9.5% vs 4.9%, respectively; odds ratio 2.81, P = 0.09) and reduced IH area (-31.8%; P = 0.04) and thickness (-28.9%; P = 0.04). External stenting was associated with improved FP I, II and III rates (odds ratio 2.84, P = 0.01), reduced IH area (-19.5%; P < 0.001) and thickness (-25.0%; P < 0.001) in the open-harvest group and reduced IH area (-12.7%; P = 0.01) and thickness (-9.5%; P = 0.21) in the endoscopic-harvest group. CONCLUSIONS: A post-hoc analysis of the VEST III trial showed that open harvesting is associated with improved overall SVG patency and reduced IH. External stenting reduces SVG disease progression, particularly with open harvesting.

Blood lactate predicts mortality after surgical repair of type A acute aortic dissection.

BACKGROUND: Ischemia and malperfusion are strong predictors of poor postoperative outcomes in type A acute aortic dissection (TAAAD). Serum lactate is an accurate surrogate point-of-care marker of malperfusion. The aim of this study is to investigate the correlation between lactate, in-hospital outcomes, and 1-year survival following TAAAD repair. METHODS: One hundred and thirty-two patients underwent operative repair of TAAAD over a 4-year period at our institution 128 patients had serum lactate measurements at three stages peri-operatively-preoperatively, at the end of cardiopulmonary bypass (post-CPB) and 6 h postintensive care unit (ICU) admission. The primary outcomes were in-hospital mortality and 1-year survival. The secondary outcomes were the incidences of in-hospital morbidities. RESULTS: Patients were divided into two groups: 88 (68.8%) with normal lactate and 40 (31.2%) with elevated lactate (>2.2 mmol/L). Lactate measured preoperatively (odds ratio 1.52, 95% confidence interval 1.17-2.07, p < .01), post-CPB (1.34, 1.14-1.64, p < .01) and 6 h post-ICU admission (1.29, 1.08-1.55, p < .01) was an independent predictor of in-hospital mortality. Following adjustment for the Penn Classification, lactate continued to have a significant correlation with in-hospital mortality at all three timepoints. There was a higher incidence of complications in the elevated lactate group and especially hemofiltration (20% vs. 9.1%, p = .08). 1-year survival was similar in both groups (p = .23). CONCLUSIONS: There is a direct correlation between elevated serum lactate and postoperative mortality after TAAAD repair, which is independent of the Penn Classification status on admission.

External stenting and disease progression in saphenous vein grafts two years after coronary artery bypass grafting: A multicenter randomized trial.

OBJECTIVES: Little data exist regarding the potential of external stents to mitigate long-term disease progression in saphenous vein grafts. We investigated the effect of external stents on the progression of saphenous vein graft disease. METHODS: A total of 184 patients undergoing isolated coronary artery bypass grafting, using an internal thoracic artery graft and at least 2 additional saphenous vein grafts, were enrolled in 14 European centers. One saphenous vein graft was randomized to an external stent, and 1 nonstented saphenous vein graft served as the control. The primary end point was the saphenous vein graft Fitzgibbon patency scale assessed by angiography, and the secondary end point was saphenous vein graft intimal hyperplasia assessed by intravascular ultrasound in a prespecified subgroup at 2 years. RESULTS: Angiography was completed in 128 patients and intravascular ultrasound in the entire prespecified cohort (n = 51) at 2 years. Overall patency rates were similar between stented and nonstented saphenous vein grafts (78.3% vs 82.2%, P = .43). However, the Fitzgibbon patency scale was significantly improved in stented versus nonstented saphenous vein grafts, with Fitzgibbon patency scale I, II, and III rates of 66.7% versus 54.9%, 27.8% versus 34.3%, and 5.5% versus 10.8%, respectively (odds ratio, 2.02; P = .03). Fitzgibbon patency scale was inversely related to saphenous vein graft minimal lumen diameter, with Fitzgibbon patency scale I, II, and III saphenous vein grafts having an average minimal lumen diameter of 2.62 mm, 1.98 mm, and 1.32 mm, respectively (P < .05). Externally stented saphenous vein grafts also showed significant reductions in mean intimal hyperplasia area (22.5%; P < .001) and thickness (23.5%; P < .001). CONCLUSIONS: Two years after coronary artery bypass grafting, external stenting improves Fitzgibbon patency scales of saphenous vein grafts and significantly reduces intimal hyperplasia area and thickness. Whether this will eventually lead to improved long-term patency is still unknown.

Subtle aortic dissection in a patient with severe aortic regurgitation and undiagnosed bicuspid aortic valve: A case report with a literature review.

BACKGROUND AND AIM OF THE STUDY: A subtle aortic dissection can be challenging to detect despite the availability of multiple diagnostic modalities. Whilst rare, the inability to detect this variant of aortic dissection can lead to a dismal prognosis. We present an extremely rare case of a subtle aortic dissection with supra-annular aortic root intimal tear and acute severe aortic regurgitation in a patient with a bicuspid aortic valve. METHODS: Case report and literature review conserning subtle aortic dissection is provided. RESULTS: Initial concerns were either aortic dissection or infective endocarditis. Despite advanced multimodality preoperative imaging, diagnosis was made intraoperatively and a Bentall procedure with a mechanical aortic valve was performed. CONCLUSIONS: Our case along with the review of current literature emphasizes that current imaging techniques may be inadequate for diagnosis of this rare variant of aortic dissection.

Adult coronary artery bypass grafting by congenital surgeons-a propensity matched analysis.

OBJECTIVES: Surgical myocardial revascularization will be increasingly needed in adult patients with congenital heart disease. We investigated the results of coronary artery bypass grafting (CABG) performed on adults by congenital cardiac surgeons at our institution. METHODS: We conducted a retrospective, single-centre study. Adults undergoing isolated or combined CABG from 2004 to 2017 were included. Early and late outcomes were analyzed for the whole cohort. Furthermore, a propensity matched analysis was conducted comparing the results of isolated CABG between congenital and adult surgeons. RESULTS: A total of 514 and 113 patients had isolated and combined CABG for acquired heart disease, respectively. A total of 33 patients had myocardial revascularization at the time of surgery for congenital heart disease. Overall early mortality was 1.2%, the rate of re-exploration for bleeding was 4.5%, and an internal mammary artery to left anterior descending artery graft was used in 85.6% patients. One-year survival was 97.5% (96.2-98.8%), and 5-year survival was 88.0% (84.8-91.3%). After propensity matching (468 pairs), early mortality (0.6% vs 1.2%, P = 0.51), re-exploration for bleeding (3.6% vs 3.0%, P = 0.72), use of internal mammary artery to left anterior descending artery graft (92.7% vs 91.9%, P = 0.70) and late survival did not differ between congenital surgeons and adult surgeons, respectively. CONCLUSIONS: Surgical myocardial revascularization can be required for adult congenital patients in a broad spectrum of clinical situations. Despite lower volumes, congenital cardiac surgeons perform CABG safely and with results that are comparable to those of the adult surgeons at our centre.

Aortic morphological variability in patients with bicuspid aortic valve and aortic coarctation.

OBJECTIVES: This study aimed to explore aortic morphology and the associations between morphological features and cardiovascular function in a population of patients with bicuspid aortic valve, while further assessing differences between patients with repaired coarctation, patients with unrepaired coarctation and patients without coarctation. METHODS: This is a single-centre retrospective study that included patients with available cardiovascular magnetic resonance imaging data and native bicuspid aortic valve diagnosis (n = 525). A statistical shape analysis was performed on patients with a 3-dimensional magnetic imaging resonance (MRI) dataset (n = 108), deriving 3-dimensional aortic reconstructions and computing a mean aortic shape (template) for the whole population as well as for the 3 subgroups of interest (no coarctation, repaired coarctation and unrepaired coarctation). Shape deformations (modes) were computed and correlated with demographic variables, 2-dimensional MRI measurements and volumetric and functional data. RESULTS: Overall, the results showed that patients with coarctation tended towards a more Gothic arch architecture, with decreased ascending and increased descending aorta diameters, with the unrepaired-aortic coarctation subgroup exhibiting more ascending aorta dilation. Careful assessment of patients with repaired coarctation only revealed that a more Gothic arch, increased descending aorta dimensions and ascending aorta dilation were associated with reduced ejection fraction (P ≤ 0.04), increased end-diastolic volume (P ≤ 0.04) and increased ventricular mass (P ≤ 0.02), with arch morphology distinguishing patients with and without recoarctation (P = 0.05). CONCLUSIONS: A statistical shape modelling framework was applied to a bicuspid aortic valve population revealing nuanced differences in arch morphology and demonstrating that morphological features, not immediately described by conventional measurements, can indicate those shape phenotypes associated with compromised function and thus possibly warranting closer follow-up.

Effectiveness and Safety of Aprotinin Use in Thoracic Aortic Surgery.

OBJECTIVE: To determine the effectiveness and safety of aprotinin use in adult patients undergoing thoracic aortic surgery. DESIGN: Single-center, retrospective study. SETTING: All cases performed at a single university hospital. PARTICIPANTS: Between January 2004 and December 2014, 846 adult patients underwent thoracic aortic surgery. Due to missing or duplicated data on primary outcomes, 314 patients were excluded. The final sample of 532 patients underwent surgery on the thoracic aorta. INTERVENTIONS: The patients were divided in the following 2 groups: 107 patients (20.1%) received aprotinin during the surgery, which represented the study group, whereas the remaining 425 patients (79.9%) underwent surgery without the use of aprotinin. MEASUREMENTS AND MAIN RESULTS: To adjust for patient selection and preoperative characteristics, a propensity score-matched analysis was conducted. Mean total blood loss at 12 hours after surgery was similar between the 2 groups. The blood product transfusion rates did not differ in the 2 groups, except for the rate of fresh frozen plasma transfusion being significantly higher in the aprotinin group. Re-exploration for bleeding and the incidence of a major postoperative bleeding event were similar between the groups. Rates of in-hospital mortality, renal failure, and cerebrovascular accidents did not show any statistically significant difference. Aprotinin did not represent a risk factor for mortality over the long term (hazard ratio 1.14, 95% confidence interval 0.62-2.08, p = 0.66). CONCLUSIONS: The use of aprotinin demonstrated a limited effect in reducing postoperative bleeding and prevention of major bleeding events. Aprotinin did not adversely affect early outcomes and long-term survival.

Human Pericardial Fluid Contains Exosomes Enriched with Cardiovascular-Expressed MicroRNAs and Promotes Therapeutic Angiogenesis.

The pericardial fluid (PF) is contained in the pericardial sac surrounding the heart. MicroRNA (miRNA) exchange via exosomes (endogenous nanoparticles) contributes to cell-to-cell communication. We investigated the hypotheses that the PF is enriched with miRNAs secreted by the heart and that it mediates vascular responses through exosome exchange of miRNAs. The study was developed using leftover material from aortic valve surgery. We found that in comparison with peripheral plasma, the PF contains exosomes enriched with miRNAs co-expressed in patients' myocardium and vasculature. At a functional level, PF exosomes improved survival, proliferation, and networking of cultured endothelial cells (ECs) and restored the angiogenic capacity of ECs depleted (via Dicer silencing) of their endogenous miRNA content. Moreover, PF exosomes improved post-ischemic blood flow recovery and angiogenesis in mice. Mechanistically, (1) let-7b-5p is proangiogenic and inhibits its target gene, TGFBR1, in ECs; (2) PF exosomes transfer a functional let-7b-5p to ECs, thus reducing their TGFBR1 expression; and (3) let-7b-5p depletion in PF exosomes impairs the angiogenic response to these nanoparticles. Collectively, our data support the concept that PF exosomes orchestrate vascular repair via miRNA transfer.

Modulating microRNAs in cardiac surgery patients: Novel therapeutic opportunities?

This review focuses on microRNAs (miRs) in cardiac surgery, where they are emerging as potential targets for therapeutic intervention as well as novel clinical biomarkers. Identification of the up/down-regulation of specific miRs in defined groups of cardiac surgery patients can lead to the development of novel strategies for targeted treatment in order to maximise therapeutic results and minimise acute, delayed or chronic complications. MiRs could also be involved in determining the outcome independently of complications, for example in relation to myocardial perfusion and fibrosis. Because of their relevance in disease, their known sequence and pharmacological properties, miRs are attractive candidates for therapeutic manipulation. Pharmacological inhibition of individual miRs can be achieved by modified antisense oligonucleotides, referred to as antimiRs, while miR replacement can be achieved by miR mimics to increase the level of a specific miR. MiR mimics can restore the function of a lost or down-regulated miR, while antimiRs can inhibit the levels of disease-driving or aberrantly expressed miRs, thus de-repressing the expression of mRNAs targeted by the miR. The main delivery methods for miR therapeutics involve lipid-based vehicles, viral systems, cationic polymers, and intravenous or local injection of an antagomiR. Local delivery is particularly desirable for miR therapeutics and options include the development of devices specific for local delivery, light-induced antimiR, and vesicle-encapsulated miRs serving as therapeutic delivery agents able to improve intracellular uptake. Here, we discuss the potential therapeutic use of miRNAs in the context of cardiac surgery.

Right internal thoracic artery or radial artery? A propensity-matched comparison on the second-best arterial conduit.

OBJECTIVES: We conducted propensity score matching to determine whether the use of the right internal thoracic artery (RITA) confers a survival advantage when compared with the radial artery (RA) as second arterial conduit in coronary artery bypass grafting. METHODS: The study population included a highly selected low-risk group of patients who received the RITA (n = 764) or the RA (n = 1990) as second arterial conduit. We obtained 764 matched pairs that were comparable for all pretreatment variables. A time-segmented Cox regression model that stratified on the matched pairs was used to investigate the effect of treatment on late mortality. RESULTS: After a mean follow-up of 10.2 ± 4.5 years (maximum 17.3 years), survival probabilities at 5, 10, and 15 years were 96.4% ± 0.7% versus 95.4% ± 0.7%, 91.0% ± 1.1% versus 89.1% ± 1.2%, and 82.4% ± 1.9% versus 77.2% ± 2.5% in the RITA and RA groups, respectively. During the first 4 years, RITA and RA were comparable in terms of mortality (hazard ratio [HR], 1.00; 95% confidence interval [CI], 0.56-1.78; P = .98). However, after 4 years RITA was associated with a significant reduction in late mortality (HR, 0.67; 95% CI, 0.48-0.95; P = .02). RITA was superior to RA when the experimental conduit was used to graft the left coronary system (HR, 0.69; 95% CI, 0.47-0.99; P = .04) but not the right coronary system (HR, 0.98; 95% CI, 0.59-1.62; P = .93). CONCLUSIONS: In a highly selected low-risk group of patients, the use of the RITA as second arterial conduit instead of the RA was associated with better survival when used to graft the left but not the right coronary artery.

Current Experience With Acute Type B Aortic Dissection: Validity of the Complication-Specific Approach in the Present Era.

BACKGROUND: Our group proposed in 1992 a "complication-specific approach" for the management of acute aortic dissection type B (TBAD), with uncomplicated cases being treated with medical therapy. In this study, we evaluate the efficacy of this management in in-hospital and postdischarge survival. METHODS: Between 1999 and 2014, 123 consecutive acute TBAD patients were treated at our institution. We compared complicated (rupture/impending rupture, malperfusion, expansion) vs uncomplicated TBAD, as well as TBAD with a dissection flap vs intramural hematoma/penetrating aortic ulcer. RESULTS: A total of 103 patients (84%) were strictly managed according to the complication-specific approach, with 93% in-hospital survival. Twenty deviated from complication-specific approach management (triaged to operation by complication-specific approach, but inoperable for a variety of reasons). Independent risk factors for a complicated course in the dissection flap subgroup (n = 89) were history of coronary artery disease (odds ratio. 3.139; p = 0.04) and maximum aortic diameter exceeding 5 cm (odds ratio, 4.586; p = 0.005). Uncomplicated patients were treated medically with antiimpulse therapy. Among the 103 patients treated with the complication-specific approach, long-term survival was 83%, 78%, 71% and 47% at 1, 3, 5, and 10 years, respectively. Between the uncomplicated and complicated groups, 8-year survival was 55% and 49%, respectively (log-rank p = 0.03). Uncomplicated patients showed comparable 6-year survival (log-rank p = 0.06) to matched normal population controls. CONCLUSIONS: Patients managed with the complication-specific approach showed an overall satisfactory long-term survival over 10 years. No in-hospital deaths occurred in patients with uncomplicated, medically treated acute TBAD, with comparable long-term survival to a matched normal population. These good long-term results provide counterbalancing perspective when considering routine thoracic endovascular aortic repair for all TBAD patients.

Oxygen delivery during cardiopulmonary bypass (and renal outcome) using two systems of extracorporeal circulation: a retrospective review.

OBJECTIVES: To investigate the combined influence of blood flow and haemodilution with either a miniaturized (Mini-CPB) or a conventional cardiopulmonary bypass (C-CPB) circuit on average oxygen delivery during bypass. The influence of this on clinical outcome, particularly renal dysfunction after routine coronary artery bypass surgery (CABG), was measured. METHODS: Retrospective analysis in two groups of 160 patients based on the surgeon's preference for bypass circuit. We compared consecutive patients undergoing isolated CABG surgery by two surgeons using Mini-CPB with a matched cohort of patients, from the same period, undergoing isolated CABG surgery by four other surgeons using a C-CPB. No trial-related intervention occurred. Data on bypass circuit parameters and clinical outcomes were acquired from routinely collected data sources. RESULTS: Average cardiopulmonary bypass pump flow was significantly lower with Mini-CPB compared with C-CPB. Mini-CPB resulted in significantly less haemodilution. The resultant calculated average oxygen delivery provided by the two systems was the same. Percentage change in plasma creatinine was significantly and inversely related to the oxygen delivery during CPB. There was no difference in percentage change in plasma creatinine between groups. The risk of having Acute Kidney Injury Network (AKIN) score ≥ 1 increased 1% for every 1 ml min(-1) m(-2) decrease in oxygen delivery (P = 0.0001, OR 0.990, 95% CI 0.984-0.995). CONCLUSIONS: Despite aiming for the same target pump flow, periodic limitations of venous return to the pump resulted in a significant reduction in average flow delivered to the patient by Mini-CPB. Less haemodilution compensated for this reduction, so that the average oxygen delivery was the same. The association between oxygen delivery and postoperative change in plasma creatinine was evident in both groups. Further work to understand whether there is a particular cohort of patients who benefit (or are put at risk) by one method of CPB vs the other is warranted.