Occurrence, predictors, and management of late vascular complications following extracorporeal membrane oxygenation.

OBJECTIVE: Vascular complications (VCs) associated with extracorporeal membrane oxygenation (ECMO) during index hospitalization are prevalent and associated with increased mortality. Few studies have evaluated late VCs following ECMO; this study aims to assess occurrence and management practices of late VCs following discharge. METHODS: A retrospective single-institution review was performed of all patients surviving initial hospitalization after being cannulated for central or peripheral veno-venous (VV) or veno-arterial (VA) ECMO between January 1, 2019, and December 31, 2020. Primary outcomes were to categorize and determine the rate of late VCs. Late VCs were defined as any cannulated vessel injury resulting from ECMO cannulation presenting after discharge from index hospitalization. Analysis was conducted by cannulated vessel and stratified by VV or VA ECMO configurations. RESULTS: A total of 229 patients were identified, of which 50.6% (n = 116) survived until discharge. Late VCs occurred in 7.8% of the surviving cohort (n = 9/116); with a median time until presentation of 150 days (interquartile range, 83-251 days). The most common late VC was infection (n = 5; 55.6%) followed by progression to limb-threatening ischemia (n = 4; 44.4%). Urgent procedures were required in 55.6% of patients (n = 5), whereas 44.4% (n = 4) were elective interventions. Interventions performed for management of late VCs included lower extremity arterial revascularization (n = 6; 66.7%), major (n = 1; 11.1%) or minor amputation (n = 1; 11.1%), and wound debridement (n = 1; 11.1%). The majority of patients presenting with late VCs had initially been cannulated for peripheral VA ECMO (n = 8; 88.9%), and one patient (11.1%) was cannulated for peripheral VV ECMO. VCs during index hospitalization were seen in 77.8% of patients (n = 7) returning with late VCs. Odds for late VCs were significantly increased in patients that had been cannulated for ECMO as part of extracorporeal cardiopulmonary resuscitation (odds ratio, 8.4; P = .016) and in cases where patients had experienced an index VC during index hospitalization (odds ratio, 19.3; P = .001). CONCLUSIONS: Late vascular complications after peripheral ECMO cannulation are not rare, particularly after arterial cannulation. Patients should be followed closely early after surviving ECMO with wound evaluation and formal assessment of perfusion with ankle-branchial indices in the cannulated limb.

Plasma Exosome Hemoglobin Released During Surgery Is Associated With Cardiac Injury in Animal Model.

BACKGROUND: Patients with valvular heart disease require cardiopulmonary bypass and cardiac arrest. Here, we test the hypothesis that exosomal hemoglobin formed during cardiopulmonary bypass mediates acute cardiac injury in humans and in an animal model system. METHODS: Plasma exosomes were collected from arterial blood at baseline and 30 minutes after aortic cross-clamp release in 20 patients with primary mitral regurgitation and 7 with aortic stenosis. These exosomes were injected into Sprague-Dawley rats and studied at multiple times up to 30 days. Tissue was examined by hematoxylin and eosin stain, immunohistochemistry, transmission electron microscopy, and brain natriuretic peptide. RESULTS: Troponin I levels increased from 36 ± 88 ng/L to 3622 ± 3054 ng/L and correlated with exosome hemoglobin content (Spearman r = 0.7136, < .0001, n = 24). Injection of exosomes isolated 30 minutes after cross-clamp release into Sprague-Dawley rats resulted in cardiomyocyte myofibrillar loss at 3 days. Transmission electron microscopy demonstrated accumulation of electron dense particles of ferritin within cardiomyocytes, in the interstitial space, and within exosomes. At 21 days after injection, there was myofibrillar and myosin breakdown, interstitial fibrosis, elevated brain natriuretic peptide, and left ventricle diastolic dysfunction measured by echocardiography/Doppler. Pericardial fluid exosomal hemoglobin content is fourfold higher than simultaneous plasma exosome hemoglobin, suggesting a cardiac source of exosomal hemoglobin. CONCLUSIONS: Red blood cell and cardiac-derived exosomal hemoglobin may be involved in myocardial injury during cardiopulmonary bypass in patients with valvular heart disease.

Endovascular Repair of an Ascending Aorta Dissection After Self-expanding TAVR by Suprasternal Approach.

Management of rare ascending aortic complications after transcatheter aortic valve replacement (TAVR) remains a poorly defined area of knowledge. Furthermore, because most patients undergoing TAVR are at intermediate to high surgical risk, the treatment of such complications often requires endovascular approaches. Herein, we present a novel technique of endovascular ascending aorta stent graft delivery from the innominate artery for the treatment of a type A aortic dissection after self-expandable TAVR implantation, specifically addressing the landing of the aortic stent within the crown of the TAVR valve.

Rescue of False Lumen Frozen Elephant Trunk Deployment Intraoperatively.

Endovascular devices have become increasingly available, which has led to an increase in use of frozen elephant trunk stents for extended repair during type A aortic dissection. Frozen elephant trunk deployment is usually done under direct visualization of both the true and false lumen but rarely, the endograft can inadvertently end in the false lumen. This can lead to false lumen pressurization and end-organ malperfusion. Herein we describe a novel intraoperative rescue technique for misplaced frozen elephant trunk into the false lumen, easily executed in a standard operating room using transesophageal echocardiography and intravascular ultrasound guidance.

Early outcomes following transatrial transcatheter mitral valve replacement in patients with severe mitral annular calcification.

OBJECTIVE: Implantation of a transcatheter valve-in-mitral annular calcification (ViMAC) has emerged as an alternative to traditional surgical mitral valve (MV) replacement. Previous studies evaluating ViMAC aggregated transseptal, transapical, and transatrial forms of the procedure, leaving uncertainty about each technique's advantages and disadvantages. Thus, we sought to evaluate clinical outcomes specifically for transatrial ViMAC from the largest multicenter registry to-date. METHODS: Patients with symptomatic MV dysfunction and severe MAC who underwent ViMAC were enrolled from 12 centers across the United States and Europe. Clinical characteristics, procedural details, and clinical outcomes were abstracted from the electronic record. The primary end point was all-cause mortality. RESULTS: We analyzed 126 patients who underwent ViMAC (median age 76 years [interquartile range {IQR}, 70-82 years], 28.6% female, median Society of Thoracic Surgeons score 6.8% [IQR, 4.0-11.4], and median follow-up 89 days [IQR, 16-383.5]). Sixty-one (48.4%) had isolated mitral stenosis, 25 (19.8%) had isolated mitral regurgitation (MR), and 40 (31.7%) had mixed MV disease. Technical success was achieved in 119 (94.4%) patients. Thirty (23.8%) patients underwent concurrent septal myectomy, and 8 (6.3%) patients experienced left ventricular outflow tract obstruction (7/8 did not undergo myectomy). Five (4.2%) patients of 118 with postprocedure echocardiograms had greater than mild paravalvular leak. Thirty-day and 1-year all-cause mortality occurred in 16 and 33 patients, respectively. In multivariable models, moderate or greater MR at baseline was associated with increased risk of 1-year mortality (hazard ratio, 2.31; 95% confidence interval, 1.07-4.99, P = .03). CONCLUSIONS: Transatrial ViMAC is safe and feasible in this selected, male-predominant cohort. Patients with significant MR may derive less benefit from ViMAC than patients with mitral stenosis only.

Hemodilution in high-risk cardiac surgery: Laboratory values, physiological parameters, and outcomes.

BACKGROUND: Acute normovolemic hemodilution (ANH) is a blood conservation strategy in cardiac surgery, predominantly used in coronary artery bypass graft (CABG) and/or valve procedures. Although higher complexity cardiac procedures may benefit from ANH, concerns for hemodynamic instability, and organ injury during hemodilution hinder its wider acceptance. Laboratory and physiological parameters during hemodilution in complex cardiac surgeries have not been described. STUDY DESIGN AND METHODS: This observational cohort (2019-2021) study included 169 patients who underwent thoracic aortic repair, multiple valve procedure, concomitant CABG with the aforementioned procedure, and/or redo sternotomies. Patients who received allogeneic blood were excluded. Statistical comparisons were performed between ANH (N = 66) and non-ANH controls (N = 103). ANH consisted of removal of blood at the beginning of surgery and its return after cardiopulmonary bypass. RESULTS: Intraoperatively, the ANH group received more albumin (p = .04) and vasopressor medications (p = .01), while urine output was no different between ANH and controls. Bilateral cerebral oximetry (rSO2 ) values were similar before and after hemodilution. During bypass, rSO2 were discretely lower in the ANH versus control group (right rSO2 p = .03, left rSO2 p = .05). No differences in lactic acid values were detected across the procedural continuum. Postoperatively, no differences in extubation times, intensive care unit length of stay, kidney injury, stroke, or infection were demonstrated. DISCUSSION: This study suggests hemodilution to be a safe and comparable blood conservation technique, even without accounting for potential benefits of reduced allogenic blood administration. The study may contribute to better understanding and wider acceptance of ANH protocols in high-risk cardiac surgeries.

Suprasternal Versus Transfemoral Access for Transcatheter Aortic Valve Replacement: Insights From a Propensity Score Matched Analysis.

Background Suprasternal access is an alternative access strategy for transcatheter aortic valve replacement (TAVR) where the innominate artery is cannulated from an incision above the sternal notch. To date, suprasternal access has never been compared with transfemoral TAVR. Thus, we sought to assess safety, feasibility, and early clinical outcomes between suprasternal and transfemoral access for patients undergoing TAVR. Methods and Results We evaluated patients from 2 institutional prospective, observational registries containing 1348 patients. Patients were selected in a 2:1 ratio (transfemoral:suprasternal) on the basis of propensity score matching. The primary outcome was in-hospital mortality, and secondary outcomes included the incidence of ischemic stroke, major bleeding, vascular injury, left bundle-branch block, and permanent pacemaker implantation at 30-day follow-up. Propensity score matching identified 89 patients undergoing suprasternal TAVR and 159 patients undergoing transfemoral TAVR suitable for analysis. There was no significant difference between suprasternal TAVR and transfemoral TAVR with respect to in-hospital mortality (1.1% versus 0.6%; odds ratio [OR], 1.80; 95% CI, 0.11-29.06; P=0.680). No patients in either cohort suffered an ischemic stroke. The incidence of major bleeding (2.2% versus 2.5%; OR, 0.89; 95% CI, 0.16-4.96; P=0.895) and vascular injury (1.1% versus 1.9%; OR, 0.59; 95% CI, 0.06-5.77; P=0.651) did not differ significantly. The frequency of left bundle-branch block (9.4% versus 15.8%; OR, 0.56; 95% CI, 0.24-1.30; P=0.177) and permanent pacemaker implantation (11.2% versus 5.9%; OR, 2.01; 95% CI, 0.75-5.45; P=0.169) were not statistically significantly different. Conclusions Suprasternal TAVR was safe and achieved promising short-term clinical outcomes when compared with transfemoral TAVR. Future studies seeking to identify the optimal alternative access site should evaluate suprasternal TAVR access alongside other substitutes for transfemoral TAVR.

Effects of acute normovolemic hemodilution on post-cardiopulmonary bypass coagulation tests and allogeneic blood transfusion in thoracic aortic repair surgery: An observational cohort study.

BACKGROUND AND AIM: Perioperative blood transfusion is associated with increased morbidity and mortality. Acute normovolemic hemodilution (ANH) is a blood conservation strategy associated with variable success, and rarely studied in more complex cardiac procedures. The study aim was to evaluate whether ANH improves coagulopathy and reduces blood transfusions in thoracic aortic surgeries. METHODS: Single-center observational cohort study comparing ANH and standard institutional practice in patients who underwent thoracic aortic repair with cardiopulmonary bypass (CPB) from 2019 to 2021. RESULTS: A total of 89 patients underwent ANH and 116 standard practice. There were no significant differences between the groups in terms of demographic or major perioperative characteristics. In the ANH group coagulation tests before and after transfusion of autologous blood showed decreased INR and increased platelets, fibrinogen, all with p < 0.0005. Coagulation results in the ANH and control groups were not statistically different. The average number of transfused allogeneic products per patient was lower in the ANH versus control group: FFP 1.1 ± 1.6 versus 1.9 ± 2.3 (p = 0.003), platelets 0.6 ± 0.8 versus 1.2 ± 1.3 (p = 0.0008), and cryoprecipitate 0.3 ± 0.7 versus 0.7 ± 1.1 (p = 0.008). Reduction in red blood cell transfusion was not statistically significant. The percentage of patients who received any transfusion was 53.9% in ANH and 59.5% in the control group (p = 0.42). There was no significant difference in major adverse outcomes. CONCLUSIONS: ANH is a safe blood conservation strategy for surgical repairs of the thoracic aorta. Laboratory data suggests ANH can improve some coagulation values after separation from CPB, and significantly reduce the number of transfused FFP, platelets and cryoprecipitate.

Acute traumatic injury of the aorta: presentation, diagnosis, and treatment.

Despite advances in detection and treatment, acute traumatic aortic injury (ATAI) is associated with high rates of morbidity and mortality. Both physical and hemodynamic forces have been postulated as mechanisms of aortic injury during a traumatic event. For patients who survive the initial injury, rapid detection is critical for diagnosis and procedural planning, which requires a thorough knowledge of both its clinical presentation and the available diagnostic imaging modalities. Radiography, computed tomography (CT), and magnetic resonance imaging (MRI) can each have a role in the diagnosis of ATAI. After stabilization of the patient, the management of ATAI is guided by the severity of injury. Appropriately selected patients with low grade injuries may be managed non-operatively. When treatment is required, there are both open surgical and endovascular options. In current practice, endovascular approaches with stent-graft placement are preferred due to their high clinical success and low rates of complications. Complications from endograft placement can include: endoleak, endograft collapse, infection, endograft failure, and endograft migration. Open surgical repair is now reserved for patients with unfavorable anatomy for endovascular therapies. This review provides a comprehensive overview of ATAI including its epidemiology and demographics, mechanisms of injury, clinical and radiographic diagnosis, treatment options, and post-therapeutic follow-up.

Snare-Assisted Delivery for Ascending Endovascular Repair of Acute Type A Dissection.

Endovascular stenting of the ascending aorta has been described for various aortic pathologies, including type A dissection in patients who are prohibitive risk for open surgery. Endovascular treatment of ascending aortic pathology poses unique anatomic and technical challenges related to aortic morphology. Herein, we present a novel technique of endovascular ascending stent graft delivery from a transfemoral approach for treatment of an acute type A dissection, utilizing a snare-guided deployment technique to facilitate favorable device deployment.

Left Anterior Thoracotomy Minimally Invasive Aortic Valve Replacement Following Left Pneumonectomy.

We report the case of a 59-year-old man referred for aortic valve replacement for severe, symptomatic aortic insufficiency who underwent a minimally invasive left anterior thoracotomy aortic valve replacement. This approach was facilitated by his history of a left pneumonectomy for lung cancer 7 years prior to presentation, which resulted in a significant left mediastinal shift. The cannulation strategy and exposure were analogous to what would be expected from a standard right anterior thoracotomy minimally invasive aortic valve replacement. The minimally invasive approach allowed for early extubation and mobilization in a patient with moderate baseline pulmonary dysfunction.

Total Endovascular Arch Repair Using Needle Fenestration and Extracorporeal Membrane Oxygenation.

There remains a clinical need for endovascular repair of the ascending aorta and the aortic arch in patients who are prohibitively high risk for open surgical repair. Herein we present a case of a total endovascular arch repair by means of a novel technique for graft fenestration using a trans-septal needle with extracorporeal membrane oxygenation support. Although the use of trans-septal needle fenestration use has been described, the use in arch fenestrations has not. We present this case as an example of techniques that may be useful in the expanding landscape of endovascular ascending and arch repair.

Contemporary suprasternal transcatheter aortic valve replacement: A multicenter experience using a simple, reliable alternative access approach.

OBJECTIVES: To describe outcomes after suprasternal (SS) transcatheter aortic valve replacement (TAVR) as a new alternative access approach. BACKGROUND: There still remains a cohort of the TAVR population who are not suitable for a transfemoral (TF) approach. SS-TAVR is a safe and effective alternative to TF-TAVR and has now become our preferred alternative access route. METHODS: We retrospectively reviewed all patients from New York Presbyterian Hospital, Columbia University Medical Center and Princeton Baptist Medical Center who underwent SS-TAVR from 2015 to July 2018. A total of 84 patients were included in the study. RESULTS: Technical success was achieved in all cases. Thirty-day survival was 98.8% (n = 83). There were minimal complications. Most notably, there were no transient ischemic attacks or strokes (0%, n = 0). Reexploration for bleeding was 3.6% (n = 3), and major bleeding was 1.7% (n = 1). We also achieved satisfactory results with a mean aortic valve gradient of 6.07 ± 3.79 mmHg and an aortic valve area of 2.21 ± 0.51 cm2 . No patients had anything more than mild paravalvular leak. The mean length of stay (LOS) in the intensive care unit was 1.42 ± 1.23 days, and hospital LOS was 4.20 ± 3.29 days. CONCLUSIONS: SS access for TAVR is an extremely important technique to have in any valve team's alternative access armamentarium. This technique can be safely and reliably reproduced with any standard hybrid operating room setup and no additional equipment, and it can be used with any commercially available valve system. In the current experience, minimal complications and excellent early term results were obtained.

Concomitant true and false lumen "parallel thoracic endovascular aortic repair" as an endovascular alternative to open arch/descending aortic reconstruction for chronic DeBakey type I dissection with aneurysmal degeneration.

A 77-year-old woman presented with symptomatic thoracic aortic aneurysm within a dissected thoracoabdominal aorta distal to a previous Dacron ascending aortic replacement. She was not a candidate for open repair and had no proximal landing zone for conventional thoracic endovascular aortic repair (TEVAR) resulting from dissection extension into the brachiocephalic vessels. A concomitant parallel graft true and false lumen TEVAR was performed from the distal aortic arch to diaphragm. Follow-up imaging demonstrated successful exclusion of the false lumen aneurysm and successful protection of the true lumen with the adjacent parallel TEVAR device.

Double mattress suture lines for valve-sparing aortic root replacement.

Valve sparing aortic root replacement remains a complex procedure despite various improvements that have been made to this operation. Specifically, a hemostatic proximal anastomosis is one of the most important factors for successful completion of the operation without complication. Here we describe a double mattress suture line technique, which facilitates a secure and hemostatic proximal suture line.

Imaging in patients with severe mitral annular calcification: insights from a multicentre experience using transatrial balloon-expandable valve replacement.

AIMS: To investigate valve sizing and the haemodynamic relevance of the predicted left ventricular outflow tract (LVOT) in patients with mitral annular calcification (MAC) undergoing transatrial transcatheter valve implantation (THV). METHODS AND RESULTS: In total, 21 patients undergoing transatrial THV, multiplanar reconstruction (MPR), maximum intensity projection (MIP), and cubic spline interpolation (CSI) were compared for MA sizing during diastole. In addition, predicted neo-LVOT areas were measured in 18 patients and correlated with the post-procedural haemodynamic dimensions. The procedure was successful in all patients (100%). Concomitant aortic valve replacement was performed in eight patients (43%) (AVR group). Sizing using MPR and MIP yielded comparable results in terms of area, perimeter, and diameter, whereas the dimensions obtained with CSI were systematically smaller. The simulated mean systolic neo-LVOT area was 133.4 ± 64.2 mm2 with an anticipated relative LVOT area reduction (neo-LVOT area/LVOT area × 100) of 59.3 ± 14.7%. The systolic relative LVOT area reduction, but not the absolute neo-LVOT area, was found to predict the peak (r = 0.69; P = 0.002) and mean (r = 0.65; P = 0.004) post-operative aortic gradient in the overall population as well as separately in the AVR (peak: r = 0.91; P = 0.002/mean: r = 0.85; P = 0.002) and no-AVR (peak: r = 0.89; P = 0.003/mean: r = 0.72; P = 0.008) groups. CONCLUSION: In patients with severe MAC undergoing transatrial transcatheter valve implantation, MPR, and MIP yielded comparable annular dimensions, while values obtained with CSI tended to be systematically smaller. Mitral annular area and the average annular diameter appear to be reliable parameters for valve selection. Simulated relative LVOT reduction was found to predict the post-procedural aortic gradients.

Usefulness of two- and three-dimensional transesophageal echocardiography in combined mitral valve-in-valve implantation and paraprosthetic leak closure.

We demonstrate the usefulness of two- and live/real time three-dimensional transesophageal echocardiography in a procedure, which combined transcatheter mitral valve-in-valve deployment and paraprosthetic leak closure in the same setting using the less invasive transfemoral approach in an adult patient with bioprosthetic mitral valve degeneration. We also highlight the additive value of three-dimensional echocardiography over the two-dimensional technique.

Transcatheter Aortic Valve Replacement by a Novel Suprasternal Approach.

BACKGROUND: Transcatheter aortic valve replacement (TAVR) provides therapy for patients with severe aortic stenosis at extreme, high, or intermediate surgical risk. Transfemoral access has been the preferred access route; however, this approach is not suitable for many TAVR candidates. A suprasternal approach may allow for earlier ambulation and shorter hospital stay as compared with other, nontransfemoral approaches. METHODS: A total of 11 patients with unsuitable transfemoral access underwent suprasternal TAVR. Propensity matching was used to compare suprasternal patients to patients undergoing transaortic, transapical, and trans-subclavian TAVR. RESULTS: Groups were well matched for baseline characteristics. A self-expanding valve device was used in 6 (54.5%) and a balloon-expandable valve in 5 (45.5%) of the 11 patients treated by the suprasternal route. Suprasternal and trans-subclavian patients were able to ambulate earlier than patients treated by the transaortic route, a median 1.6 days (interquartile range [IQR]: 0.9 to 1.8), 1.6 days (IQR: 0.9 to 2.7), and 3.9 days (IQR: 1.9 to 4.5) after the procedure for suprasternal, trans-subclavian, and transaortic patients, respectively (p = 0.001). Length of hospitalization was shorter for patients treated by suprasternal or trans-subclavian access in comparison with patients treated by the transaortic or transapical approach: median 4 days (IQR: 3 to 8) and 4 days (IQR: 4 to 8) versus 8 days (IQR: 6 to 14) and 6 days (IQR: 7 to 11) for suprasternal and trans-subclavian versus transaortic and transapical, respectively (p = 0.01). CONCLUSIONS: Suprasternal and trans-subclavian access are associated with earlier ambulation and shorter hospitalization than other nontransfemoral TAVR routes, without an increase in complications. Further study is required to determine if suprasternal is the alternative access of choice for TAVR patients with poor transfemoral vasculature.