Partial Sternotomy Research Articles

Direct comparison of mechanical circulatory support devices in porcine model of acute myocardial infarction complicated by ventricular septal defect and cardiogenic shock

Abstract Introduction Despite urgent clinical need, until now optimal strategy for mechanical circulatory support in acute myocardial infarction (AMI) complicated by ventricular septal defect (VSD) and cardiogenic shock has not been determined. Purpose The aim of our study was to compare hemodynamic effects of intra-aortic balloon pump (IABP), extracorporeal membrane oxygenation (ECMO) and Impella CP in the animal model of AMI complicated by VSD and cardiogenic shock. Methods Under general anesthesia and mechanical ventilation in pigs (sus scrofa domestica), using partial sternotomy, AMI was induced by ligation of left anterior descending. VSD was simulated by insertion of 25F cannulas into the left and right ventricles and their extracorporeal connection by 3/8 tubes generating left-to-right shunt. The hemodynamic effect of ECMO (2 L/min), IABP, and Impella CP (2 L/min) was evaluated by the measurement of the left ventricular end-diastolic pressure (LVEDP), mean arterial pressure (MAP), carotid flow (CAR) as a surrogate of total circulatory output, and VSD flow. Data are presented as mean (SD), P < 0.05 was considered statistically significant. Results Eleven animals were used, one died after induction of AMI, ten pigs completed all study procedures. Baseline (no mechanical support) LVEDP was 13.8 (3.0) mmHg, MAP 54.5 (11.0) mmHg, CAR 290.9 (37.3) mL/min, and VSD 1174.0 (499.3) mL/min (Table 1). IABP significantly improved all parameters in comparison to Baseline (Table 1). ECMO significantly improved MAP and CAR not only in comparison to Baseline but also in comparison to IABP and Impella; on the other hand, ECMO increased VSD flow (Table 1). Impella significantly improved all parameters with the largest effect on LVEDP and VSD flow (Table 1). Conclusions All tested devices improved the key hemodynamic parameters of MAP and CAR, however each to different extent. Individual devices influenced differently LVEDP and VSD flow. The results of this study may help in selection of optimal therapeutic strategy in AMI complicated by VSD and cardiogenic shock.Table 1.Hemodynamic outcomes.

514. ESOPHAGOGASTRIC ANASTOMOSIS STRICTURE AFTER A CERVICAL FISTULA: LONG TERM COMPLICATION AFTER THE MCKEOWN PROCEDURE STERNOTOMY APPROACH: ANASTOMOSIS RESECTION

Abstract Background Anastomotic stricture after anastomotic leakage is a common long term complication after mckeown procedure. It can be resolved by endoscopic dilations on most occasions. However, if endoscopic aproach fail, we have to solve the estenosis with a surgery procedure. This type of reintervention could be a really hard aproach due to an intense fibrosis and anatomical layer destructuring. In this video, we show a initial cervical approach to do a anastomosis resection and reanastomosis. However, due to the intense fibrosis and the difficulty in dissecting the gastric plasty from the sternal table, the incision had to be extended and a partial sternotomy was performed. With this approach, we can see the gastric plasty, making the dissection. The we can perform a new esophagus gastric anastomosis safety. In conclusion, partial sternotomy allows us to visualize the gastric plasty and perform the dissection safety making a tensión free anastomosis. https://we.tl/t-6MTce26lI1

Minimally invasive versus conventional methods for aortic root surgery: Choosing the right approach.

Partial upper sternotomy is preferred for isolated aortic valve replacement because of its optimal surgical visibility and favorable cosmetic outcomes; however, it is not commonly used for aortic root surgery, and the conventional median sternotomy is still the preferred method for most surgeons. We aimed to compare the safety and effectiveness of a minimally invasive approach (partial sternotomy [PS]) and conventional approach (median sternotomy [FS]) for aortic root surgery. Patients who underwent aortic root surgery at our hospital from 2016 to 2021 were retrospectively enrolled and divided into two groups. After propensity score matching, the conventional group included 156 patients and the minimally invasive group-57 patients. Bicuspid aortic valves were observed in 63 (40.4%) and 33 (57.9%) patients in the FS and PS groups, respectively. Valve-sparing surgery was performed on 69 (44.2%) and 30 (52.6%) patients in the FS and PS groups, respectively. The minimally invasive approach was beneficial in terms of blood loss during the first 24 h after surgery (p = 0.029) and postoperative blood transfusion (p = 0.023). The survival rates and freedom from reoperation or severe aortic regurgitation after the David procedure were comparable between the standard and minimally invasive groups (p = 0.25; p = 0.66) at mid-term follow-up. A minimally invasive approach for aortic root surgery can be safely performed as the standard approach. Partial upper sternotomy has the advantage of lower blood loss in the early postoperative period and does not negatively affect the results of valve-sparing root replacement.

Brachiocephalic Artery Access Without Sternotomy in Older Asian Patients Undergoing Transcatheter Aortic Valve Replacement

There are numerous approaches for transcatheter aortic valve replacement (TAVR); however, access-related complications remain a point of concern. We analyzed consecutive patients who underwent TAVR for severe aortic stenosis via the brachiocephalic artery (BCA) without sternotomy (TBc group, n = 10) and via the trans-ascending aortic (TAo group, n = 8). The median BCA diameter and distance between the access point and suprasternal notch or superior margin of the clavicle were 11.3 mm and 8.3 mm, respectively. No patients in the TBc group underwent a partial sternotomy. Compared with the TAo group, the TBc group exhibited a shorter mean procedure time and lower blood loss volume as well as shorter duration of hospitalization. TAVR through the BCA may be a safe and feasible alternative for ascending aorta access. Studies with longer follow-up analysis and more patients are warranted to confirm our findings.

Isolated or Combined Ascending Aortic Replacement through a Partial Sternotomy: Early and Midterm Outcomes

Abstract Background We aimed to investigate the in-hospital and midterm outcomes of patients undergoing ascending aortic replacement (AAR) through a partial or a full sternotomy approach through a propensity matching analysis. Methods We retrospectively included all patients (n = 167) who underwent elective AAR in our institution between 2013 and 2020. The study population was divided into two groups according to the surgical access (40 patient in the partial sternotomy or “PS” group and 127 in the full sternotomy or “FS” group). Due to the significant differences between the groups, a propensity matching of 1:3 was applied. In-hospital complications, survival, and reoperation at follow-up were investigated. Results The PS group showed higher cross-clamp and cardiopulmonary bypass times than the FS group (94.2 vs. 83 minutes and 164.2 vs. 126.8 minutes, respectively). Moreover, the postoperative ventilation time was significantly higher in the PS group, but it did not affect the length of stay in the intensive care unit (ICU). The incidences of bleeding, stroke, and mortality were comparable between the two groups (11 vs. 3%, 3 vs. 6%, and 5 vs. 3%, respectively). After a median follow-up of 2 ± 1.98 years, the Kaplan–Meier analysis showed no significant differences between the two groups (log-rank, p = 0.17) in terms of survival. Conclusion The surgical ascending aorta replacement through a partial sternotomy is associated with longer operative times, but this does not affect the early as well as the long-term follow-up.

Partial versus Complete Sternotomy for Aortic Valve Replacement—Multicenter Study

Abstract Background The benefits of minimally invasive techniques in cardiac surgery remain poorly defined. We evaluated the short- and mid-term outcomes after surgical aortic valve replacement through partial upper versus complete median sternotomy (MS) in a large, German multicenter cohort. Methods A total of 2,929 patients underwent isolated surgical aortic valve replacement via partial upper sternotomy (PUS, n = 1,764) or MS (n = 1,165) at nine participating heart centers between 2016 and 2020. After propensity-score matching, 1,990 patients were eligible for analysis. The primary end point was major adverse cardiac and cerebrovascular events (MACCE), a composite of death, myocardial infarction, and stroke at 30 days and in follow-up, up to 5 years. Secondary end points were acute kidney injury, length of hospital stay, transfusions, deep sternal wound infection, Dressler's syndrome, rehospitalization, and conversion to sternotomy. Results Unadjusted MACCE rates were significantly lower in the PUS group both at 30 days (p = 0.02) and in 5-year follow-up (p = 0.01). However, after propensity-score matching, differences between the groups were no more statistically significant: MACCE rates were 3.9% (PUS) versus 5.4% (MS, p = 0.14) at 30 days, and 9.9 versus 11.3% in 5-year follow-up (p = 0.36). In the minimally invasive group, length of intensive care unit (ICU) stay was shorter (p = 0.03), Dressler's syndrome occurred less frequently (p = 0.006), and the rate of rehospitalization was reduced significantly (p < 0.001). There were 3.8% conversions to full sternotomy. Conclusion In a large, German multicenter cohort, MACCE rates were comparable in surgical aortic valve replacement through partial upper and complete sternotomies. Shorter ICU stay and lower rates of Dressler's syndrome and rehospitalization were in favor of the partial sternotomy group.

Anterolateral thoracotomy with partial sternotomy: a feasible approach for treating the complex pathology of the aortic arch.

Our goal was to review our surgical experiences in patients with complex pathologies of the aortic arch who have undergone anterolateral thoracotomy with a partial sternotomy (ALPS). From October 2019 to November 2023, a total of 23 patients underwent one-stage repairs of complex pathologies of the aortic arch through the ALPS approach. The mean age was 61.9 ± 16.7 years old. The aortic pathologies were as follows: aorta-related infection in 11 (aorto-oesophageal fistula: 4, graft infection: 6, native aortic infection: 1); aortic dissection in 9 including shaggy aorta in 2, non-dissecting aneurysm in 1, and coarctation of the aorta (CoA) in 2. Eighteen patients underwent aortic replacement from either the sinotubular junction or the ascending aorta to the descending aorta; 1 patient underwent it from the aortic root to the descending aorta (redo Bentall procedure and extensive aortic arch replacement); 3 patients underwent it from the aortic arch between the left carotid artery and left subclavian artery to the descending aorta; and 1 patient underwent a descending aortic replacement. Ten patients underwent omentopexy, latissimus dorsi muscle flap installation or both procedures. The hospital mortality rate was 13.0% (3/23). The overall survival and freedom from aortic events were 73.3%±10.2% and 74.1%±10.2%, respectively, at the 3-year follow-up. There was an absence of aorta-related deaths, and no recurrent infections were identified. The short-term outcomes using the ALPS approach for the treatment of complex pathologies of the aortic arch were acceptable. Further studies will be required to determine the long-term results.

Health-related quality of life after minimal-invasive treatment of aortic valve stenosis in the elderly.

Although transfemoral transcatheter aortic valve implantation (TF-TAVI) offers superior early outcome over open surgical aortic valve replacement (SAVR) in the elderly, a comparison of TF-TAVI with surgery performed through partial upper mini sternotomy (PUMS) hasn't yet been validated. The aim of the present study is to evaluate the clinical outcome and quality of life of patients subjected to TF-TAVI and open surgical aortic valve replacement through partial upper mini sternotomy (PUMS-SAVR). Baseline, procedural and post-treatment data of 197 consecutive patients: 137 TF-TAVI and 60 PUMS-SAVR treated at Philipps University of Marburg, were retrospectively collected. The propensity score method was used to create two groups in a 1:1 fashion. Questionnaire assessment (SF36_LQ) of quality of life of the matched patients was carried out at the ambulant routine control presentation. A competing risk regression model is used to evaluate the impact of the clinical outcome on health-related quality of life (HrQoL). After propensity matching, TF-TAVI remained associated with lower procedural time (136±50 vs. 298±36 min, P<0.01), intensive care unit stay (2.68±2.70 vs. 4.29±2.43 days, P<0.01), transfusion of packed red cell units (0.46±2.05 vs. 1.60±2.00 U, P=0.02) and higher heart block (42.86% vs. 0%, P<0.01) and permanent pacemaker implantation rates (14.29% vs. 0%, P=0.05) compared to PUMS-SAVR. TF-TAVI is associated with less complains, superior HrQoL (excellent 40% and very good 60% vs. very good 100% in PUMS). Partial sternotomy is the main predictor of the inferior HrQoL, with the regression coefficient of -1.11 (95% confidential interval, -1.503 to -0.726; R2=0.324, P<0.0001). Transfusion (P=0.26), paravalvular leakage (0.618), pacemaker implantation (P=0.19) and delirium (P=0.92) did not influence HrQoL after the minimal-invasive treatment of aortic valve stenosis in elderly patients. Although PUMS-SAVR offers better technical outcomes with less permanent pacemaker implantation and less paravalvular leakage than TF-TAVI, it is still associated with more need for transfusion, longer ventilation-and intensive care unit-times, and prolonged hospital stay. In the elderly, PUMS-SAVR achieves inferior quality of life compared to TF-TAVI. Partial sternotomy reveals as the strongest risk factor of perceived health-level post-treatment. It remains to be revealed whether fast-track open heart surgery that maintains a fully intact sternum and allows immediate postoperative extubation-as performed through video-assisted mini-thoracotomy or thoracoscopic robotic procedures with percutaneous cannulation - should be favored against PUMS-SAVR.

Redo extended thoracic aortic replacement from aortic root to descending aorta via anterolateral thoracotomy with partial sternotomy for graft infection

A 59-year-old male underwent Bio-Bentall + total arch replacement with a frozen elephant trunk for acute type A aortic dissection before at another hospital. He was diagnosed as mediastinitis and previous graft infection, followed by wound closure with omental flap installation. However, the recurrent graft infection from the aortic root to the FET in the descending aorta was diagnosed by 18-fluorodeoxyglucose positron emission tomography. Redo modified Bio-Bentall procedure, total arch replacement, and descending aortic replacement for previous graft infection using anterolateral thoracotomy with partial sternotomy was successfully performed. Anterolateral thoracotomy with partial sternotomy provided not only the excellent exposure from the aortic root to the descending aorta but also sure myocardial protection with antegrade and selective delivery of cold crystalloid cardioplegia and stable brain protection with antegrade selective cerebral perfusion. The patient is doing well without recurrent of infection after 2 years of the operation.

Our experience with robotic-assisted thymic surgery.

Thoracic surgery is increasingly influenced by the development of minimally invasive approaches which have also influenced surgery in the area of the anterior mediastinum. The previously standard approach to the thymus via partial sternotomy was gradually replaced by the videothoracoscopic approach in most cases. In recent years, robotically assisted surgery has been gaining ground worldwide in this area, as well. The aim of our paper is to provide a comprehensive overview of procedures in the field of the thymus, including their indications, and to share our first experience with robot-assisted thymus surgery. At the 3rd Department of Surgery, since the start of the robot-assisted thymus surgery program, 23 thymectomies have been performed using this approach, of which 17 were performed for thymoma, 3 for myasthenia gravis, and 3 for parathyroid adenoma localized in thymus tissue. From our experience and the available data, it follows that the length of hospitalization, the rate of complications and the resulting effect of robot-assisted procedures is comparable to VTS procedures; however, the robot-assisted surgery also allows for mini-invasive treatment even in significantly obese patients and in patients with advanced thymic tumors who would otherwise be indicated for open thymectomy.

Suprasternal approach for insertion of Impella 5.5 into the proximal right subclavian artery

The Impella 5.5 (Abiomed) is a percutaneous, temporary left ventricular assist device (LVAD) that serves as an important method of treatment of acute cardiogenic shock refractory to medical management. The Impella 5.5 and 5.0 are commonly inserted through the right axillary artery; however, this may be limited by inadequate vessel diameter to accommodate the Impella and inadequate vessel quality. A central approach to Impella 5.5 incision has been described in the pediatric population, particularly via the innominate artery through a suprasternal and/or neck incision, with success. As an alternative to axillary Impella placement, we propose the usage of a limited suprasternal incision for Impella 5.5 insertion in the adult population, either through the proximal right subclavian artery or the distal innominate artery. This may offer multiple advantages, such as increased vessel diameter and quality of more proximal vessels, avoidance of partial sternotomy, avoidance of a second infraclavicular wound site if the patient progresses to require LVAD or transplant, avoidance of lymphatic and nerve injury through the axillary exposure, ease of manipulation for repositioning, and patient rehabilitation. Potential limitations include difficulty due to body habitus, potential risk of stroke with the innominate approach, and wound complications. A central approach is a reasonable alternative to axillary Impella placement in patients with inadequate axillary artery caliber, defined as less than 6–7 mm diameter, poor artery quality to accommodate anastomosis, and small body habitus, allowing for ease of exposure.

Single-vessel access venoarterial extracorporeal membrane oxygenation and Impella technique for acute cardiogenic shock complicated by lung congestion.

The combination of the Impella and peripheral venoarterial extracorporeal membrane oxygenation (Ecmella) is a promising treatment for critically ill patients. We report a single-access Ecmella approach using the brachiocephalic artery. A 65-year-old woman with acute myocardial infarction involving the left main coronary artery underwent intra-aortic balloon pump and peripheral venoarterial extracorporeal membrane oxygenation (VA-ECMO) placement. Given the progression of pulmonary congestion and lower limb ischaemia, and an axillary artery diameter of 4.9 mm, we decided to perform a single Ecmella approach. A Y-shaped 9-mm Dacron woven graft was anastomosed to the brachiocephalic artery through a reverse T-shaped partial sternotomy. The Impella 5.5 and arterial cannula of VA-ECMO were introduced through each graft. Six days after, VA-ECMO was removed. Sixty-two days after the surgery, the patient received durable left ventricle assist device implantation. In conclusion, haemodynamic support using a single-access Ecmella through brachiocephalic artery allows for managing patients with narrow peripheral arteries.

The Feasibility of Less-Invasive Bentall Surgery: A Real-World Analysis.

Minimally invasive approaches are being used increasingly in cardiac surgery and applied in a wider range of operations, including complex aortic procedures. The aim of this study was to examine the safety and feasibility of a partial upper sternotomy approach for isolated elective aortic root replacement (a modified Bentall procedure). We performed a retrospective analysis of 768 consecutive patients who had undergone isolated Bentall surgery between January 2000 and January 2021 at our institution, with the exclusion of re-operations, endocarditis, acute aortic dissections, and root replacement with major concomitant procedures such as multi-valve or coronary bypass surgery. A total of 98 patients were operated on via partial sternotomy (PS) and were matched 2:1 to 196 patients operated on via full sternotomy (FS). The procedure time was 12 min longer in the PS group (205 min vs. 192.5 min in the FS group, p = 0.002), however, cardiopulmonary bypass and aortic cross-clamp times were comparable between groups. Eight PS-procedures were converted to full sternotomy, predominantly for bleeding complications (n = 6). Re-exploration for acute bleeding was necessary in 11% of the PS group and 4.1% of the FS group (p = 0.02). Five FS patients and none in the PS group required emergency coronary bypass grafting for postoperative coronary obstruction (p = 0.2). PS patients were hospitalized for a significantly shorter period (9.5 days vs. 10.5 days in the FS group, respectively). There were no significant differences regarding in-hospital (p = 0.4) and mid-term mortality (p = 0.73), as well as for other perioperative complications. Performing Bentall operations via partial upper sternotomy is associated with similar perfusion and cross-clamp times, as well as overall mortality, when compared to a full sternotomy approach. A low threshold for conversion to full sternotomy should be accepted if limited access proves insufficient for the handling of intraoperative complications, particularly bleeding.

Intra-aortic band impairs transapical device implantation in a pig: a case report

BackgroundAnatomic anomalies in the ascending aorta may impair the implantation and testing of cardiovascular devices in humans and animal models.Case presentationWe present the rare case of an intra-aortic band in a German Landrace pig. During terminal animal testing, the band hindered the implantation of a left ventricular assist device (LVAD) with transventricular outflow graft across the aortic valve. After lower partial sternotomy, epicardial echocardiography displayed an intraluminal echogenic structure at the sinotubular junction causing unspecific flow turbulences. Under cardiopulmonary bypass, coring of the left ventricular apex was performed. Due to strong resistance in the proximal aorta, accurate positioning of the transventricular LVAD outflow graft was impossible. After euthanasia, necropsy revealed a fibrous band located at the sinotubular junction, dividing the lumen of the ascending aorta.ConclusionsThe occurrence of an intra-aortic band represents an extremely rare case of a most likely congenital anomaly. Awareness of such anomalies is important for planning and performing animal testing. Perioperative echocardiography may help to either remove such anomalies or allow discontinuing the procedure prior to device implantation.

Anterior Access to the Cervicothoracic Junction via Partial Sternotomy: A Clinical Series Reporting on Technical Feasibility, Postoperative Morbidity, and Early Surgical Outcome.

Surgical access to the cervicothoracic junction (CTJ) is challenging. The aim of this study was to assess technical feasibility, early morbidity, and outcome in patients undergoing anterior access to the CTJ via partial sternotomy. Consecutive cases with CTJ pathology treated via anterior access and partial sternotomy at a single academic center from 2017 to 2022 were retrospectively reviewed. Clinical data, perioperative imaging, and outcome were assessed with regards to the aims of the study. A total of eight cases were analyzed: four (50%) bone metastases, one (12.5%) traumatic instable fracture (B3-AO-Fracture), one (12.5%) thoracic disc herniation with spinal cord compression, and two (25%) infectious pathologic fractures from tuberculosis and spondylodiscitis. The median age was 49.9 years (range: 22-74 y), with a 75% male preponderance. The median Spinal Instability Neoplastic Score (SINS) was 14.5 (IQR: 5; range: 9-16), indicating a high degree of instability in treated cases. Four cases (50%) underwent additional posterior instrumentation. All surgical procedures were performed uneventfully, with no intraoperative complications. The median length of hospital stay was 11.5 days (IQR: 9; range: 6-20), including a median of 1 day in an intensive care unit (ICU). Two cases developed postoperative dysphagia related to stretching and temporary dysfunction of the recurrent laryngeal nerve. Both cases completely recovered at 3 months follow-up. No in-hospital mortality was observed. The radiological outcome was unremarkable in all cases, with no case of implant failure. One case died due to the underlying disease during follow-up. The median follow-up was 2.6 months (IQR: 23.8; range: 1-45.7 months). Our series indicates that the anterior approach to the cervicothoracic junction and upper thoracic spine via partial sternotomy can be considered an effective option for treatment of anterior spinal pathologies, exhibiting a reasonable safety profile. Careful case selection is essential to adequately balance clinical benefits and surgical invasiveness for these procedures.

BIO5: Durability of HeartMate 3 Apical Cuff to Left Ventricle Anastomosis Using an Automated Rapid Anastomotic Device in a Chronic Bovine Model

Background: We developed an automated rapid anastomotic device for HeartMate 3 (HM3) standard apical cuff to Left Ventricle (AC-LV) anastomosis. Tissue anchors and compression plates axially compress the apical cuff sewing skirt to the myocardium. A low-profile delivery tool with integrated targeting system deploys all tissue anchors synchronously. The fixation mechanism minimizes myocardial impact because it confines tissue engagement to the area under the apical cuff sewing skirt. In acute bovine experiments (n=5), HM3 AC-LV anastomoses took less than 1 minute and had excellent hemostasis that was maintained at inotrope-induced supraphysiologic stresses (LV pressures 210-247 mmHg). The purpose of this study was to demonstrate HM3 AC-LV anastomotic durability in chronic bovine implants. Methods: Three calves (weight range 105-123 Kg) underwent HM3 AC-LV anastomosis on the beating heart by lower partial sternotomy with our anastomotic device. Thereafter, cardiopulmonary bypass (CPB) was initiated (ACT >400 seconds), 2 cm. diameter full-thickness LV cores were removed using an Abbott coring tool, and a custom-made sintered titanium plug was inserted to occlude the apical cuff. CPB was weaned, and AC-LV anastomotic hemostasis was assessed qualitatively by Likert Scale (1=unacceptable, 2 = poor, 3 = average, 4 = good, 5 = excellent). Pericardial and bilateral pleural chest tubes (CT) were placed. Serial hematocrit (HCT) and CT outputs were recorded. Anticoagulation was IV heparin at 12 hours, then warfarin through necropsy. Necropsies (gross and microscopic) were done at 56, 57, and 62 days by an experienced independent pathologist. Tissue anchor and compression plate position stability were assessed by acute vs. chronic photograph comparisons. Results: Implants times were 17, 20, and 17 sec. CPB time range was 6-9 min. Acute hemostasis was Likert Scale 5 (excellent) in all cases. At 24 hours, HCT exceeded intra-operative baseline in all animals (range: +2% - +3%) and remained stable. Forty-eight-hour CT output range was 514-760ml. There were no transfusions. In all cases necropsy demonstrated minimal pericardial/pleural adhesions; dense fibrous implant incorporation; stable tissue anchor/compression plate positions; no pseudoaneurysms; concentric smooth fibrous scar at the core site epicardial surface to AC junction (see figure); and implant site histology comparable to manual anastomosis. Conclusion: Rapid automated HM3 AC – LV anastomosis was hemostatic and durable. Additional advantages are greatly reduced operative time; uniform implant technique; precise apical cuff implant site targeting; guaranteed clearance for HM3 pump coupling; facilitates minimal access implant; and minimized myocardial impact (facilitates implant in smaller hearts/ potential to improve recovery). With modifications other LVADs Apical Cuffs can be accommodated, and derivative access ports can facilitate intracardiac device delivery.Figure 1. Concentric smooth fibrous scar at core site epicardial-apical cuff junction

CARD10: Transapical Left Ventricular Assist Device Implantation Using a Novel Accessory in Swine

Background: Conventional left ventricular assist devices (LVADs) require an anastomosis of the outflow graft to the ascending aorta. We developed and tested a LVAD accessory, which combines pump in- and transaortic outflow in a dual lumen adapter, thus, allowing LVAD implantation solely via the left ventricular apex. Methods: The LVAD accessory (Fig. A) consisted of a 3D printed titanium inflow and a 12 mm outflow stent graft. The accessory in combination with a centrifugal LVAD (HeartMate 3, HM3, Abbott, USA) was implanted in 10 adult female Landrace pigs (104 ± 13 kg). A balloon catheter (14 mm Atlas Gold PTA Dilatation Catheter, BD, USA) was introduced via the left femoral artery and placed in the left ventricle. After lower partial sternotomy, pericardiotomy and fixation ring attachment, apical coring was performed in a standard fashion on the beating heart using cardiopulmonary bypass. The balloon was exteriorized, inflated in the outflow graft and both, the accessory with the attached outflow graft, were pulled into the left ventricle and the aorta. The accessory was attached to the fixation ring. The LVAD was connected and deaired, and the balloon catheter was removed. Results: After successful LVAD implantation in all animals, echocardiography revealed no signs of aortic or mitral regurgitation. In eight animals ramp testing was performed. The HM3 flow estimate increased from 3.7 ± 1.2 L/min at 4’500 rpm to 5.4 ± 1.2 L/min at 7’200 rpm (Fig. B). Post-mortem examination (Fig. C) revealed correct placement of the LVAD accessory with the inflow in the left ventricle (blue arrow) and the outflow graft across the aortic valve (yellow arrow). There were neither signs of damage of the aortic (*) or mitral valve (+) nor signs of thrombosis. Conclusion: The novel accessory in combination with a centrifugal LVAD allowed safe and less-invasive LVAD implantation. Ramp testing revealed effective left ventricular support in the acute swine model. Further testing in a chronic heart failure model will be performed to validate these results.

Use of Ethanol Injections to Create a Complete Atrioventricular Block in a Rat Model

Complete atrioventricular block (AVB) is an abnormal heart rhythm resulting from a defect in the cardiac conduction system. Patients with complete AVB are at risk of symptoms ranging from syncope or hypotension to cardiovascular collapse or sudden cardiac death. A reliable animal model of complete AVB is essential for understanding the mechanisms underlying the fatal hemodynamic effects and alterations in electrical conductivity associated with this arrhythmia. We evaluated the use of ethanol injections in a systematic surgical approach to create a complete AVB model in rats. We used eight Sprague Dawley rats (8 weeks old, 220 ± 30 g): four received a 70% ethanol injection in the AV node, and four received a similar injection of 0.9% sodium chloride. Our surgical approach involved performing a partial sternotomy, using the epicardial fat as a landmark for ethanol injections. Animals were followed for 7 and 14 days. Complete AVB was successfully induced in all four rats that received ethanol injections. Rats in the control group experienced a transient AVB with a return to sinus rhythm. Our study found that using 70% ethanol injections in a systematic surgical approach is a reliable, safe, and reproducible way of creating a complete AVB model in rats.

Left ventricular assist device exchange from HeartMate II to HeartMate 3 in an Asian patient—a case report and literature review

BackgroundPump exchange surgery of left ventricular assist device (LVAD) has been demonstrated in several studies; however, information for Asian patients was limited.Case presentationA 63-year-old man underwent a pump upgrade from HeartMate II to HeartMate 3 for driveline damage through limited left anterior thoracotomy and lower partial sternotomy. He did not experience any hemodynamic adverse events or device malfunction during postoperative follow-ups of 12 months. We also reviewed all published cases with HeartMate II exchange to HeartMate 3.ConclusionsThe case demonstrated that it was safe and feasible to perform HMII LVAD exchange to HM3 through a limited approach for Asian patients.

Right anterolateral thoracotomy with partial sternotomy for chronic type B aortic dissection with right aortic arch and Kommerell's diverticulum.

Chronic type B aortic dissection with the right aortic arch was rare. We present the case of a 59-year-old man with a right aortic arch and chronic type B aortic dissection, with a maximum size of 80 mm. Graft replacement was successfully performed through right anterolateral thoracotomy with partial sternotomy through the fourth intercostal space. The patient's postoperative course was uneventful. He had no paralysis and was extubated on postoperative day 2 and discharged from the hospital on postoperative day 15. Anterolateral thoracotomy with partial sternotomy could be a suitable approach for right-sided aortic aneurysms.