How to Treat Type B Aortic Dissections in the Presence of an Aberrant Right Subclavian Artery: A Systematic Review.

An aberrant right subclavian artery (ARSA) is the most common congenital variant of the aortic arch. Usually, this variation is largely asymptomatic, but sometimes it may be involved in aortic dissection (AD). Surgical management of this condition is challenging. The therapeutic options have been enriched in recent decades by establishing individualized endovascular or hybrid procedures. Whether these less invasive approaches bear advantages, and how they have changed the treatment of this rare pathology, is still unclear. Therefore, we conducted a systematic review. We performed a review of literature from the past 20 years (from January 2000 until February 2021) complying with the Preferred Reporting Items for Systematic Reviews and Meta-analyses guidelines. All reported patients treated for Type B AD in the presence of an ARSA were identified and classified into three groups according to the received therapy (open, hybrid, and total endovascular). Patient characteristics, as well as in-hospital mortality, and major and minor complications were determined and statistically analyzed. We identified 32 relevant publications comprising 85 patients. Open arch repair has been offered to younger patients, but significantly less often in symptomatic patients needing urgent repair. Therefore, the maximum aortic diameter was also significantly larger in the open repair group compared with that in the hybrid or total endovascular repair group. Regarding the endpoints, we did not find significant differences. The literature review revealed that open surgical therapies are preferred in patients presenting with chronic dissections and larger aortic diameters, most likely because they are unsuitable for endovascular aortic repair. Hybrid and total endovascular approaches are more often applied in emergency situations, where aortic diameters remain smaller. All therapies demonstrated good, early, and midterm outcomes. But, these therapies carry potential risks in the long term. Therefore, long-term follow-up data are urgently needed to validate that these therapies are sustainable.

Aortic valve construction using new nitinol templates and pericardial tissue.

The use of pericardial tissue has been widely adopted in a range of cardiac surgery procedures involving the reconstruction of heart valves. Its use in aortic valve construction has been discussed in recent years by Ozaki et al. A key parameter in the optimal functioning of a fabricated valve is the sizing of the new cusps. This video tutorial demonstrates aortic valve construction using newly designed templates and forceps to facilitate sizing and enhance the symmetrical coaptation of the new cusps.

Aortic valve construction using pericardial tissue: short-term single-centre outcomes.

OBJECTIVES: Aortic valve construction using pericardial tissue has been known since the late 1960s. The procedure was re-introduced by Ozaki in 2010 and is currently used to treat specific aortic valve diseases. The exact sizing of the neo-cusps and the insertion of the commissures remain the keys to success when performing this procedure. We evaluated our experience using modified custom-made templates. METHODS: In this prospective single-centre study, we evaluated 52 consecutive patients who underwent aortic valve construction between September 2015 and March 2017 using either autologous (16 patients, 30.8%) or tissue-engineered pericardium (36 patients, 69.2%). Most patients (34, 65.4%) presented with aortic stenosis or endocarditis (5, 9.6%). Twenty patients had bicuspid and 5 had unicuspid valves. A modified sizing technique with specially designed templates was used. The primary end point was early death; the secondary end points were major adverse cardiac and cerebrovascular events, freedom from reoperation and overall mortality rate. Echocardiographic follow-up was performed intraoperatively and at 12-month intervals. RESULTS: The mean age was 60 ± 14 years; 63.5% were men; and 34 (65.4%) patients had combined procedures. The mean cross-clamp time was 99 ± 17 min. Early outcomes included 1 stroke, 2 patients needing short-term dialysis and 1 death. During follow-up (mean 11.2 ± 4.8 months), trace aortic regurgitation was observed in 4 patients; the mean pressure gradient was 6.8 ± 2.9 mmHg. Three patients died later (of non-cardiac reasons), and 5 patients needed reoperation due to endocarditis. CONCLUSIONS: Aortic valve construction using pericardial tissue could be an alternative in middle-age patients presenting with aortic valve disease in whom valve repair was not possible. The newly designed templates allow exact sizing of the neo-cusps and optimal commissure implantation; however, long-term follow-up in a larger cohort is warranted to assess the durability of the neo-valves.

Modified sizing technique with newly designed tools to facilitate the valve sparing aortic root replacement "David" procedure with mid-term results.

BACKGROUND: Valve sparing root replacement differs in specific points. The main target remains to achieve a perfect intraoperative result and long-term stability. We aimed in this study to present our modified sizing technique for valve-sparing "David" procedure and its mid-term results. METHODS: We present a retrospective single-center study. A newly designed sizing ring in addition to triple-armed forceps (Trifeet®) was used to measure the proper size of the Valsalva® prosthesis for patients undergoing David-procedure. Primary endpoints are intraoperative aortic regurgitation (AR) and early postoperative outcomes. Secondary endpoints included freedom from aortic regurgitation or reoperation and overall mortality. RESULTS: A total of 63 consecutive patients who underwent David procedure between 09/2012 and 12/2016 were evaluated. Mean age was 52±15 years and 76.2% were male. Moderate to severe aortic regurgitation was reported in 60 (95.2%) patients. Four (6.3%) patients presented with type-A aortic dissection, 20 (31.7%) patients had bicuspid and 3 (4.8%) had a unicuspid aortic valve, 2 (3.2%) patients had a prior aortic valve repair. Intraoperative echocardiography revealed no 34 (54%), trace 26 (41.2%) or moderate 3 (4.8%) AR. Stroke, myocardial infarction, and 30-day mortality occurred in 1 patient (1.6%). During follow-up 5 (7.9%) patients needed reoperation due to recurrent AR within a mean of 35±18 months. One could be re-repaired, and the other four underwent aortic valve replacement. A second patient died in the late follow-up. CONCLUSIONS: Our modified sizing technique simplifies the "David-procedure" and allows to achieve a good intraoperative and mid-term results. However, these results have to be confirmed in a larger cohort with a long-term follow-up.

Endoscopy in aortic valve repair: does it worth it?

BACKGROUND: Aortic valve repair (AVR) is a technically challenging procedure. Usually, the repaired valve is checked after weaning from cardiopulmonary bypass (CPB). We aimed to evaluate intraoperative and clinical outcomes of AVR patients in whom intraoperative aortic root endoscopy was applied. METHODS: The present study was a retrospective single-center study. An autoclavable video-scope was used to evaluate aortic valve. During endoscopy, crystalloid cardioplegia was administered to pressurize the aortic root. Primary endpoints were: need for Re-CPB after weaning from bypass and early postoperative aortic valve regurgitation. Secondary endpoints included: 30-day mortality and freedom from aortic regurgitation/reoperation during follow-up. RESULTS: A total of 66 consecutive patients who underwent AVR (05/2014-03/2017) were evaluated. Patients mean age was 53.5±14.5 years and 74.2% were male. Seventy-three percent of the patients were in New York Heart Association (NYHA) functional class III/IV. The main underlying aortic valve pathology was aortic valve regurgitation in 83.3%, 9.1% aortic stenosis and combination of both in 7.6%. A tricuspid or bicuspid aortic valve was observed in 48.5% and 43.9%, respectively, whereas 7.6% showed a functional unicuspid aortic valve. Intraoperative results revealed endoscopy as a helpful tool, where second time cross-clamp was avoided in most (58, 87.9%) of patients. Thirty-day mortality was 3.0%. During follow-up (28±10 months), 2 patients required re-operation due to recurrent aortic valve regurgitation. CONCLUSIONS: The present analysis showed, that intraoperative aortic valve endoscopy is a helpful tool to evaluate AVR before weaning from bypass. This easy-to-use tool gives real-time information about the intraoperative result and might provide additional guidance to achieve optimal results after AVR.

Transcatheter versus Surgical Aortic Valve Replacement after Previous Cardiac Surgery: A Systematic Review and Meta-Analysis.

AIM: Aortic valve replacement (AVR) in patients with prior cardiac surgery might be challenging. Transcatheter aortic valve replacement (TAVR) offers a promising alternative in such patients. We therefore aimed at comparing the outcomes of patients with aortic valve diseases undergoing TAVR versus those undergoing surgical AVR (SAVR) after previous cardiac surgery. METHODS AND RESULTS: MEDLINE, EMBASE, and the Cochrane Central Register were searched. Seven relevant studies were identified, published between 01/2011 and 12/2015, enrolling a total of 1148 patients with prior cardiac surgery (97.6% prior CABG): 49.2% underwent TAVR, whereas 50.8% underwent SAVR. Incidence of stroke (3.8 versus 7.9%, p=0.04) and major bleeding (8.3 versus 15.3%, p=0.04) was significantly lower in the TAVR group. Incidence of mild/severe paravalvular leakage (14.4/10.9 versus 0%, p < 0.0001) and pacemaker implantation (11.3 versus 3.9%, p=0.01) was significantly higher in the TAVR group. There were no significant differences in the incidence of acute kidney injury (9.7 versus 8.7%, p=0.99), major adverse cardiovascular events (8.7 versus 12.3%, p=0.21), 30-day mortality (5.1 versus 5.5%, p=0.7), or 1-year mortality (11.6 versus 11.8%, p=0.97) between the TAVR and SAVR group. CONCLUSIONS: TAVR as a redo procedure offers a safe alternative for patients presenting with aortic valve diseases after previous cardiac surgery especially those with prior CABG.

Minimal access versus conventional aortic valve replacement: a meta-analysis of propensity-matched studies.

Conventional aortic valve replacement (CAVR) via a full sternotomy is the standard surgical approach for aortic valve replacement. Minimal access aortic valve replacement (MAAVR) is commonly performed via a partial sternotomy and a right minithoracotomy. Such procedures aim not only to reduce the invasiveness but to offer the same quality, safety and results of the conventional approach. Our goal was to compare both procedures by performing a meta-analysis of reports with risk adjustment that performed a propensity-matched analysis. Relevant articles were searched for in Medline, the Cochrane Database of Systematic Reviews and the Scopus database based on predefined criteria and end-points. The early and late outcomes and complications were compared in the selected studies. A total of 4558 patients from 9 studies were enrolled; 2279 (50%) underwent CAVR and 2279 (50%) underwent MAAVR. There was a significantly lower rate of postoperative low output syndrome (1.4% vs 2.3%, P = 0.05) and atrial fibrillation (11.7% vs 15.9%, P = 0.01) in the MAAVR than in the CAVR group, respectively. In contrast, aortic cross-clamp and cardiopulmonary bypass times were significantly longer in the MAAVR group (P < 0.05). Finally, the incidence of early deaths (1.5% vs 2.2%, P = 0.14), stroke (1.4% vs 2%, P = 0.20), myocardial infarction (0.4% vs 0.5%, P = 0.65), renal injury (4.5% vs 6%, P = 0.71), respiratory complications (9% vs 10.1%, P = 0.45), re-exploration for bleeding (4.9% vs 4.1%, P = 0.27) and pacemaker implantation (3.3% vs 4.1%, P = 0.31) was similar in both groups, respectively. In summary, even though MAAVR procedure, either through partial sternotomy or right minithoracotomy, provides patient satisfaction due to the smaller incision and better cosmetics, MAAVR is as safe as the CAVR procedure. Although MAAVR takes slightly longer, it was not associated with greater cardiopulmonary bypass-related adverse effects. Interestingly, MAAVR shows a lower incidence of low cardiac output syndrome and atrial fibrillation.

Impact of Liver Indicators on Clinical Outcome in Patients Undergoing Transcatheter Aortic Valve Implantation.

BACKGROUND: Liver dysfunction increases death and morbidity after cardiac operations. There are currently no data evaluating liver function in patients undergoing transcatheter aortic valve replacement (TAVR). We aimed therefore to evaluate our TAVR results in regard to liver function. METHODS: A total of 640 consecutive TAVR patients were evaluated. Of those, 11 patients presented with chronic liver disease before TAVR. The Model for End-Stage Liver Disease score was used to measure liver function in these patients. The primary study end point was 30-day mortality in patients presenting with liver dysfunction. Secondary study end point was liver enzymes after TAVR. RESULTS: The mean Model for End-Stage Liver Disease score in patients with chronic liver disease was 16.8 ± 6.2 (median, 18; range, 7 to 26). The 30-day mortality was 9.1% (57 of 629) in patients presenting without liver disease and 9.1% (1 of 11) in patients with liver disease (p = 1.00). Patients with chronic liver disease showed significantly higher preoperative levels of γ-glutamyl transpeptidase (p < 0.001). After TAVR, we observed a significant increase in alanine aminotransferase on postoperative day 3 compared with preoperative values (p < 0.001), accompanied by a decrease in albumin (p < 0.001). CONCLUSIONS: Liver cirrhosis per se is not considered as a contraindication for cardiac operations. In the present study, we did not observe a higher 30-day mortality rate in liver cirrhotic patients undergoing TAVR, suggesting TAVR as a feasible alternative with acceptable outcomes in patients with chronic liver disease. Moreover, the present study is the first to evaluate liver variables in patients undergoing TAVR.

Early and long-term cognitive outcome after conventional cardiac valve surgery.

Objectives: Adverse cognitive outcome is well recognized after coronary artery bypass grafting (CABG) while little is known about the extent and duration of decline after cardiac valve surgery. We investigated changes in cognitive function following conventional cardiac valve surgery over up to 4 years. Methods: Among 36 patients (65.2 ± 9.2 years, 36% women) who received valve surgery, we assessed serial cognitive function with a battery of 11 standardized tests across 3-4 years. Cognitive function was analysed to identify: (1) cognitive decline (i.e. within-patient changes in test scores) and (2) cognitive deficit (i.e. drop of score ≥1 SD in ≥3 tests). Diffusion-weighted magnetic resonance imaging (DW-MRI) was applied pre- and post-procedure to detect ischaemic brain injury. Data were compared to a historical cohort of 39 patients undergoing CABG. Results: After both valve surgery and CABG, a significant decline at discharge was detected in 7 of 11 cognitive tests. The rate of patients with a cognitive deficit after valve surgery vs CABG was 39% vs 56% at discharge, 14% vs 23% at 3 months, and 16% vs 26% at 3-4 years (not significant, [n.s.]). After valve surgery, DW-MRI identified 19 (53%) patients with evidence of 50 new focal ischaemic lesions (CABG: 20 [51%] patients with 42 lesions, n.s.). Cumulative cerebral ischaemic load per patient was not significantly different between the valve surgery group and CABG group (503 ± 485 mm 3 vs 415 ± 234 mm 3 ). After correction for multiple potential risk factors in both groups, reduced verbal memory at discharge could be identified as a predictor of long-term cognitive impairment in CABG patients only ( P = 0.04). For both the valve surgery and CABG group, no association between cognitive impairment and new ischaemic cerebral lesions was found. Conclusions: The course of cognitive performance after valve surgery and CABG was similar with early postoperative decline followed by subsequent recovery. Although silent small brain infarcts were present in about half of all patients, they did not impact cognitive performance neither at early nor during long-term follow-up.

Long-term experience with the E-vita Open hybrid graft in complex thoracic aortic disease†.

OBJECTIVES: The E-vita Open hybrid stent graft is intended to achieve one-stage treatment of the proximal and distal thoracic aorta down to the mid-thoracic level in cases of acute (AAD) or chronic (CAD) type I aortic dissection and complex thoracic aortic aneurysm (TAA). We report our long-term results up to 10-year experience. METHODS: From February 2005 until March 2015, 178 consecutive patients (mean age 59 ± 11 years) underwent surgery using the E-vita Open hybrid graft for AAD ( n = 96), CAD ( n = 43) or TAA ( n = 39). Pre-, intra- and postoperative variables, influential procedural improvements and follow-up data including aortic remodelling analyses are presented. RESULTS: Overall 30-day mortality was 10%, 10% for AAD, 7% for CAD and 13% for TAA. Univariable analysis identified low left ventricular ejection fraction, peripheral arterial disease, chronic obstructive pulmonary disease and severely compromised haemodynamics as risk factors for in-hospital death. Logistic regression analysis defined compromised haemodynamics and duration of cardiopulmonary bypass as significant. After 7 years, estimated survival was 55% for AAD, 74% for CAD and 73% for TAA patients. Freedom from aorta-related late death was 94%, 91% in AAD, 100% in CAD and 97% in TAA. Positive or stable aortic remodelling down to the stent graft end was achieved in 92% AAD, 82% in CAD and full aneurysmal exclusion in 88%. Further downstream, negative remodelling was observed in 27% of the AAD, 41% of the CAD and 22% of the TAA patients. Freedom from endovascular intervention downstream was 96% in AAD, 75% in CAD and 74% in TAA patients. Freedom from thoraco-abdominal surgery was 97%, 65% and 93%, respectively. CONCLUSIONS: The E-vita Open hybrid stent graft renders durable long-term performance without any proximal endoleakage or graft failure over time and represents the ideal landing or docking zone for either thoracic endovascular thoracic repair or thoraco-abdominal surgery, if required. No reinterventions were necessary down to the end of the stent graft, proving that the disease is overcome along the hybrid graft down to mid-thoracic level.

Role of regional aortic wall properties in the pathogenesis of thoracic aortic dissection.

OBJECTIVES: The mechanisms of the location and extension of acute aortic dissection (AD) are only poorly understood. The aim of this study was to compare the cohesion of the non-coronary aortic sinus (NAS) and the ascending aortic wall (AA) using the Dissectometer - a new device for analyses of the mechanical properties of the aorta. DESIGN: The properties of the aortic wall were analyzed with the "Dissectometer" (parameters P7, P8 and P9) in adult patients undergoing aortic root (AR) replacement in two different segments: NAS and AA. The aortic wall thickness (AWT) was measured with a micrometer. RESULTS: Thirty-three adult patients (mean age 65 ± 14 years, 80% male) were included in this study. The aortic wall of the NAS was significantly thinner than that of the AA (1.9 ± 0.4 vs. 2.3 ± 0.4, p < 0.01). In contrast, mechanical stability assessed by cohesion testing was diminished in AA samples compared to NAS samples (P7: 86.0 ± 55.0 vs. 152.3 ± 89.2, p < 0.01; P8: 2.5 ± 1.3 vs. 6.0 ± 3.1, p < 0.01; P9: 3.6 ± 1.4 vs. 7.8 ± 3.2, p < 0.01). CONCLUSIONS: This study shows that the wall of the AR is characterized by a thin but stable wall, whereas AA was found to be weaker despite its greater thickness. This difference might be involved in the development and spreading of aortic dissections.

Comparison of mid-term haemodynamic performance between the BioValsalva and the BioIntegral valved conduits after aortic root replacement.

OBJECTIVES: We retrospectively compared the haemodynamic performance of the BioValsalva (BV) and BioIntegral (BI) biological aortic-valved conduits in the aortic root position. METHODS: Between July 2008 and June 2014, a total of 55 patients underwent aortic root replacement using the BV conduit (n = 27) or the BI conduit (n = 28). The primary study endpoints were haemodynamic performance during follow-up, including mean pressure gradients (MPGs) and effective orifice areas (EOAs). Secondary study endpoints were early postoperative outcomes within 30 days and survival. RESULTS: Both groups did not differ in regard to demographics (BV: median age 71 years, 70.4% female; BI: median age 66 years, 85.7% female, P = 0.15 and P = 0.17) and risk profile (median EuroSCORE-II BV: 3.8 vs 5.3% for BI, P = 0.38). A total of 20% of the total patients (BV 5/27, 18.5% vs BI 6/28, 21.4%) presented with acute type-A aortic dissection. During follow-up, both groups showed no difference in MPGs for all valve sizes [BV, 11.0 mmHg (8.3-14.8 mmHg) vs BI, 11.5 mmHg (9.0-13.0), P = 0.82]. Similar results were achieved for EOAs for all valve sizes [BV, 1.85 cm(2) (1.55-2.21) vs BI, 1.80 cm(2) (1.64-1.83), P = 0.24]. Moreover, there was no statistically significant difference in aortic regurgitation (AR) with none/trace AR in (21/23) 91.3% in BV patients versus (16/21) 76.2% in BI patients (P = 0.23) at follow-up. Both groups showed a high rate of concomitant procedures (BV: 59.3% vs BI: 71.4%, P = 0.40) and emergency indication (BV: 18.5% vs BI: 21.4%, P = 0.79), resulting in an overall 30-day mortality rate of 7.3% (4/55 patients). CONCLUSIONS: The present small single-centre study is one of the first to evaluate and compare the BioValsalva and BioIntegral biological aortic-valved conduit in the aortic root position. Both conduits showed optimal haemodynamic results with a low incidence of aortic regurgitation.

Aortic remodelling in aortic dissection after frozen elephant trunk†.

OBJECTIVES: Frozen elephant trunk (FET) can be used for continuous downstream aorta treatment in acute aortic dissection (AAD) and chronic aortic dissection (CAD). The study reports the changes in the lumen volumes along the downstream aorta towards remodelling. METHODS: In 70 patients (22 CAD, 48 AAD), pre-, postoperative and at least the 1-year follow-up aortic imaging was available. Volume changes of aortic lumen (AL) and true lumen (TL) between examinations along the stent graft aortic segment (A), downstream to coeliac trunk (B) and distally to bifurcation (C) were used for quantification. TL increase >10% with stable AL or AL decrease >10% with stable TL were classified as positive, changes within a 10% threshold as stable, and all other changes as negative remodelling. RESULTS: In AAD, positive or stable remodelling occurred in A (90%), B (65%), C (58%) within 1 year, thereafter in 26 patients (follow-up: 47 ± 21 months) in A (92%), B (65%), C (62%). Negative remodelling in ≥2 segments was found in 5/26 (19%) patients. In CAD, positive or stable remodelling occurred in A (100%), B (86%), C (77%) within 1 year, thereafter in 16 patients (follow-up: 46 ± 20 months) in A (75%), B (44%), C (38%). Negative remodelling in ≥2 segments was found in 7/16 (43%) patients, 5 underwent reintervention, and stabilized thereafter. CONCLUSIONS: FET facilitates positive remodelling in AAD and CAD down to stent graft level. Distally, 20% AAD and 40% CAD patients remain at risk for secondary reintervention, and can be identified by negative remodelling in ≥2 segments in the follow-up examinations.

Urinary [TIMP-2]*[IGFBP7] for early prediction of acute kidney injury after coronary artery bypass surgery.

BACKGROUND: Acute kidney injury (AKI) is a common complication after cardiac surgery. Currently, prediction of AKI with classical tools remains uncertain. Therefore, it was the aim of the present study to evaluate two new urinary biomarkers-insulin-like growth factor-binding protein 7 (IGFBP7) and tissue inhibitor of metalloproteinases-2 (TIMP-2) in patients after coronary artery bypass surgery (CABG). METHODS: In a prospective cohort study, 60 consecutive patients undergoing isolated on-pump CABG were enrolled. Urine samples collected every 12 h in the postoperative course were analyzed for the product of TIMP-2 and IGFBP7. Urinary output, serum creatinine and estimated glomerular filtration rate (eGFR) were recorded simultaneously. Primary clinical endpoint was the development of AKI stage 2 or 3 according to the classification of the KDIGO within 48 h after surgery. RESULTS: 48 male and 12 female patients with a mean age of 69.61 ± 8.4 years were included. 19 patients developed an AKI (31.6 %), six patients met the endpoint with AKI 2 or 3 (10 %). Urinary [TIMP-2]*[IGFBP7] increased significantly as early as 4 h after CABG in patients with AKI 2/3 (1.83 ± 2.15 vs. 0.23 ± 0.45, p < 0.05) whereas serum creatinine did not increase until 48 h after surgery. The diagnostic accuracy of [TIMP 2]*[IGFBP7] on day one after surgery for the prediction of AKI 2/3 was significantly better (sensitivity 0.89, specificity 0.81, AUC 0.817, 95 % CI 0.622-1.0 SE 0.099, p = 0.022, cut-off 0.817) than for serum creatinine (AUC 0.359, sensitivity 0.50, specificity of 0.52, cut-off value 1.17 mg/dl) and eGFR. CONCLUSION: Urinary [TIMP-2]*[IGFBP7] represents a sensitive and specific biomarker to predict moderate to severe AKI very early after CABG. Analyses from our ongoing larger study are necessary to confirm these findings and probably increase sensitivity and specificity.

The investigation of systolic and diastolic leaflet kinematics of bioprostheses with a new in-vitro test method.

OBJECTIVES: We aimed to investigate leaflet kinematics of bioprostheses with a novel high-speed imaging method. MATERIAL AND METHODS: High-speed-imaging (1000 Hz) was used to evaluate leaflet kinematics of the Carpentier-Edwards Perimount Magna (PM) and Magna Ease (PME) aortic bioprostheses. Both prostheses (diameter 23 mm) were placed inside a model aorta under pulsatile flow conditions. Frequencies (F) and different stroke volumes (S) were simulated. Maximum aortic valve area (AVA), total ejection time (TET), rapid valve opening time (RVOT) and rapid valve closing time (RVCT) as well as opening (OS) and closing (CS) speeds were evaluated. RESULTS: Both bioprostheses showed different results dependent on flow conditions. The test setup was capable of identifying small AVA-differences between both valves (235 vs. 202 mm², F60/S60; 272 vs. 207 mm²; F70/S80), as well as differences in OS and CS (2.36 vs. 1.62 mm²/ms; 2.97 vs. 2.44 mm²/ms, F80/S60). TET was comparable (638 vs. 645 ms F60/S60; 341 vs. 343 ms, F90/S60), while results for RVOT and RVCT were equal, and dependent on frequency and stroke volume. CONCLUSIONS: The novel evaluation method is sensitive to detect differences between valves, although differences were found to be small. PM has a larger visible AVA associated with higher opening and closing speeds in contrast to PME.

Left subclavian artery rerouting and selective perfusion management in frozen elephant trunk surgery.

INTRODUCTION: The frozen elephant trunk (FET) technique enables combined aortic arch and descending aortic repair. We report our experience with a modified arch replacement technique by rerouting of the left subclavian artery (LSA) and fixation of the FET in Zone 2 or proximally under selective perfusion of all three arch arteries and the downstream aorta. MATERIAL AND METHODS: From January 2005 to December 2014, 78 of 173 patients operated with the FET technique underwent rerouting of the LSA. Rerouting was performed as aortic-subclavian, aorto-axillary or carotid-subclavia bypass. Hypothermic selective antegrade cerebral perfusion was established for cerebral protection. A separate cardiopulmonary bypass circuit was added for selective LSA and downstream aorta perfusion during the arch repair. RESULTS: In-hospital mortality, stroke and paraplegia rates were 10%, 8% and 2.5%, respectively. LSA rerouting enabled total arch repair in <60 minutes of selective cerebral perfusion (mean 56 ± 15). No recurrent nerve palsy occurred. The selective perfusion of the downstream aorta led to the reduction of the distal hypothermic circulatory arrest time close to 30 minutes (p < 0.0001). DISCUSSION: LSA rerouting facilitates arch aortic repair by FET surgery. The selective perfusion of all arch arteries and the downstream aorta during open arch repair reduces the ischemic times and may improve organ protection.

Detection of aortic wall instability with the new dissectometer: Correlation with histological findings.

OBJECTIVES: Although risk stratification for aortic dissection or rupture based on aortic diameter is quite suboptimal, alternative methods for the assessment of the aortic wall stability are rare. We assessed the mechanical properties of the aortic wall by a new custom-made device mimicking transversal aortic wall shear stress during open heart surgery in comparison with histological examination. MATERIAL AND METHODS: One-hundred and five aortic walls were tested by the 'dissectometer' (seven different measured and two calculated values) as well as histological examination was performed. RESULTS: Histological examination classified the aortic wall as normal in 54 (51.4%) patients and pathologic in 51 (48.6%) patients. Six out of nine parameters assessed by the dissectometer showed a significant correlation to histological findings. Using ROC-analysis, the most reliable parameter (P9) showed a sensitivity of 93.3% and a specificity of 80.4% with an area under the curve of 0.89 when using a cut-off value of 3.4. In the logistic regression analysis, P9 was an independent predictor for aortic wall instability (OR 28.983, 95% CI 11.507-72.993, p < 0.0001). CONCLUSION: The dissectometer is suitable for discriminating between stable and unstable aortic walls with a good correlation to histological examination holding promise for direct and quick intraoperative identification of aortic walls at risk for dissection.