Impact of preoperative malperfusion on postoperative outcomes in type A aortic dissection - importance of serum lactate estimation in ongoing malperfusion.

INTRODUCTION: Acute type A aortic dissection (ATAAD) is one of the most critical emergencies in cardiovascular surgery. Additional complications such as organ malperfusion can significantly decrease the chances of survival. Despite promptly performed surgical treatment, impaired organ perfusion may persist, thus close postoperative monitoring is recommended. But, is there a surgical consequence due to the existence of a preoperatively known malperfusion and is there a correlation between pre-, peri- and postoperative levels of serum lactate and proven malperfusion? METHODS: Between 2011 and 2018, 200 patients (66% male; median age: 62.5 years; interquartile range: +/-12.4 years) that received surgical treatment at our institution for an acute dissection DeBakey type I were enrolled in this study. The cohort was divided into two groups according to the preoperative existence of malperfusion and non-malperfusion. At least one kind of malperfusion occurred in 74 patients (Group A: 37%), while 126 patients (Group B: 63%) showed no evidence of malperfusion. Furthermore, lactate levels of both cohorts were differentiated into four periods: preoperative, intraoperative, 24 hours after surgery, and 2-4 days after surgery. RESULTS: The patients' status differed significantly prior to surgery. Group A (malperfusion) showed an elevated requirement for mechanical resuscitation (A: 10.8%; B: 5.6%; p: 0.173), were significantly more often admitted in an intubated state (A: 14.9%; B: 2.4%; p: 0.001) and showed higher incidences of stroke (A: 18.9% (n = 149); B: 3.2% (n = 4); p: 0.001). Levels of serum lactate from the preoperative period until days 2-4 were significantly increased in the malperfusion cohort at all times. CONCLUSIONS: Preexisting malperfusion due to ATAAD may significantly increase the chance of early mortality in patients with ATAAD. Serum lactate levels were a reliable marker for inadequate perfusion from admission until day 4 after surgery. Despite this, early intervention survival in this cohort remains limited.

Aortic Valve-Sparing Root Replacement (David I Procedure) in Adolescents: Long-Term Outcome.

INTRODUCTION: Aortic valve-sparing root replacement (David's procedure) is an especially appealing treatment option for young patients. Here, we present the short-, mid, and long-term outcomes of this operation in adolescent patients. METHODS: Between September 1994 and March 2014, 29 patients aged 6 to 21 years underwent the David-I procedure at our center. We conducted a retrospective study with follow-up. RESULTS: The mean age was 16.8 ± 3.4 years and 90% (n = 26) were male. Marfan's syndrome was present in 86% (n = 25) of cases. Ninety-seven percent (n = 28) of cases were performed electively, and one case (3%) was performed emergently for acute aortic dissection type A. There were no early perioperative deaths (0%). Follow-up, which was completed on 100% of patients, comprised a total of 394 patient years and a mean follow-up time of 13.6 ± 5.4 years. The estimates for survival at 1, 5, and 10 years after initial surgery were 100, 97, and 93%, respectively. During follow-up, there were four (14%) late deaths and five (17%) aortic valve-related reoperations. The 1-, 5-, and 10-year estimates for freedom from valve-related reoperation were 100, 86, and 83%, respectively. The perioperative mortality for these five reoperations was 0%. DISCUSSION: Aortic valve-sparing root replacement can be performed in adolescents with a very low perioperative risk. Long-term survival seems to be affected by connective tissue diseases.

Risk factors for critical limb ischemia in patients undergoing femoral cannulation for venoarterial extracorporeal membrane oxygenation: Is distal limb perfusion a mandatory approach?

BACKGROUND: Venoarterial extracorporeal membrane oxygenation support is a well-established tool in the care of severe refractory cardiac and respiratory failure. The application of this support may serve as a bridge to transplant, recovery or to implantation of a ventricular assist device. Venoarterial extracorporeal membrane oxygenation support can be administered through an open surgical access via the common femoral or axillary artery or a percutaneous approach using Seldinger technique. Both techniques may obstruct the blood flow to the lower limb and may cause a significant ischemia with possible limb loss. Malperfusion of the distal limb can be avoided using an ipsilateral distal limb perfusion, which may be established by adding a single-lumen catheter during venoarterial extracorporeal membrane oxygenation treatment to overcome the obstruction. The aim of this study is to distinguish the presence or absence of a distal limb perfusion regarding the incidence of distal limb ischemia. Furthermore, expected risk factors of open and percutaneous femoral venoarterial extracorporeal membrane oxygenation installation were evaluated for the development of distal limb ischemia. METHODS: Between January 2012 and September 2015, 489 patients received venoarterial extracorporeal membrane oxygenation support at our institution. In total, 307 patients (204 male, 103 female) with femoral cannulation were included in the analysis. The cohort was distinguished by the presence (group A; n = 237) or absence (group B; n = 70) of a distal limb perfusion during peripheral venoarterial extracorporeal membrane oxygenation treatment. Furthermore, a risk factor analysis for the development of distal limb ischemia was performed. RESULTS: The main indications for venoarterial extracorporeal membrane oxygenation therapy were a low cardiac output syndrome (LCOS) (53%) and failed weaning of extracorporeal circulation (23%). A total of 23 patients (7.49%) under venoarterial extracorporeal membrane oxygenation support developed severe distal limb malperfusion (3.38% in group A vs 21.42% in group B). Preemptive installation of distal limb perfusion extended the intervention-free intervals to 7.8 ± 19.3 days in group A and 6.3 ± 12.5 in group B. A missing distal limb perfusion (p = 0.001) was identified as a main risk factor for critical limb ischemia. Other comorbidities such as arterial occlusion disease (p = 0.738) were not statistically significantly associated. Surgical intervention due to vascular complications after extracorporeal membrane oxygenation explantation was needed in 14 cases (4.22% in group A and 5.71% in group B). CONCLUSION: We were able to identify the absence of distal limb perfusion as an independent risk factor for the development of critical distal limb ischemia during femoral venoarterial extracorporeal membrane oxygenation treatment. The application of a distal limb perfusion should be considered as a mandatory approach in the context of femoral venoarterial extracorporeal membrane oxygenation treatment regardless of the implantation technique.

Total Arterial Revascularization with Radial Artery T-grafts in Patients with Significant Left Main Stem Stenosis Is Not Associated with Higher Perioperative Risk.

BACKGROUND: Total arterial revascularization (TAR) has become a standard procedure for the treatment of coronary multivessel disease, due to the superior long-term patency rates of arterial grafts as compared with saphenous vein graft material. Controversies about the use of TAR in patients with left main coronary artery disease exist. Hence, we ought to determine whether left main coronary artery disease is a risk factor for early postoperative mortality and morbidity after TAR using the in situ left internal thoracic artery (LITA) and radial artery as composite T-graft. METHODS: A total of 904 consecutive patients were included in this retrospective study. They underwent first-time coronary artery bypass grafting surgery in our institution, receiving TAR using the in situ LITA and RA T-graft. Of these patients, 247 (27%) had left main coronary artery disease (Group LMSS) and 657 (73%) had no significant left main coronary artery stenosis (Group nLMSS). RESULTS: Results were comparable. Mortality and perioperative myocardial infarction rates were 0.4% LMSS versus 0.3% nLMSS, p = 1, and 2% LMSS versus 2% nLMSS, p = 0.81, respectively. Stroke rate, acute renal failure rate, and reoperation rates were 2% LMSS versus 1% nLMSS, p = 0.36, 7% LMSS versus 8% nLMSS, p = 0.41, and 2% LMSS versus 3% nLMSS, p = 0.5, respectively. Postoperative stay was shorter in the LMSS group (8.1 ± 4.3 days vs. 8.9 ± 6.1 days nLMSS, p = 0.048). CONCLUSION: Our perioperative results indicate that TAR in patients with left main stenosis is safe and feasible. Long-term results will have to be awaited to further evaluate prognostic outcome.

Is Bentall Procedure Still the Gold Standard for Acute Aortic Dissection with Aortic Root Involvement?

INTRODUCTION: The "ideal" treatment of acute aortic dissection type A (AADA) with dissected and dilated root is controversial. We compared the outcome of classical Bentall procedure (biological and mechanical) with valve-sparing David procedure. METHODS: Between January 2002 and July 2011, 119 patients with AADA and aortic root involvement underwent surgery at our center. Thirty-one patients (group 1) received biological conduits, 41 (group 2) received mechanical conduits, and 47 (group 3) underwent David procedures. RESULTS: Cross-clamp, cardiopulmonary bypass, and circulatory arrest times were 151 ± 52, 232 ± 84, and 36 ± 30 minutes (group 1); 148 ± 44, 237 ± 91, and 45 ± 29 minutes (group 2); and 160 ± 46, 231 ± 63, and 35 ± 17 minutes (group 3), respectively. The 30-day mortality rates were 32.3% (group 1), 22% (group 2), and 12.8% (group 3). The 1-year rates for freedom from valve-related reoperation were 100% (group 1), 92.5% (group 2), and 95.2% (group 3) (p = 0.172). The 1-year survival rates were 61% (group 1), 61% (group 2), and 84.1% (group 3) (p = 0.008). CONCLUSION: Even in AADA patients with root involvement, David procedure has acceptable results. David procedure (if possible) or a Bio-Bentall (for pathological valves) seems to be the optimal technique.

Cardiac awake extracorporeal life support-bridge to decision?

Severe acute heart failure requires immediate intensive care unit (ICU) treatment, but prognosis and outcome of further treatment regimens largely depends on the preprocedural status of the patient. Especially, multiorgan failure including mechanical ventilation are unfavorable predictors of clinical outcome. Here, we report a strategy of immediate initiation of extracorporeal life support (ECLS) in awake and spontaneously breathing patients with acute heart failure to achieve early multiorgan recovery and gain sufficient time for further treatment planning. Twenty-three patients with severe cardiac failure refractory to standard medical management underwent ECLS treatment, after first clinical signs of cardiac failure appeared to avoid mechanical ventilation. Hemodynamic parameters and renal and liver functions were monitored. Outcome at 1 and 6 months was determined. Patients 46.1 ± 15.5 years of age were placed on ECLS due to various underlying diagnosis: ischemic heart disease (n = 6), dilatative cardiomyopathy (n = 4), myocarditis (n = 2), graft failure following heart transplantation (n = 6), or other diseases (n = 5). ECLS lasted 11.9 ± 12.9 days. Hemodynamic stabilization was achieved immediately after ECLS initiation. Vasopressors were reduced subsequently and the cardiac situation improved indicated by central venous saturation, which increased from 38.5 ± 11.3% before to 74.26 ± 8.4% (P < 0.0001) 24 h after ECLS initiation. Similarly, serum lactate levels decreased from 4.7 ± 4.6 to 1.7 ± 1.51 mmol/L (P = 0.003). Cumulative 30-day survival was 87.5%, and 6-month survival was 70.8%. In acute cardiac failure, early ECLS treatment is a safe, feasible treatment in awake patients allowing a gain of time for final decision. Moreover, this strategy avoids complications associated with sedation and mechanical ventilation and leads to recovery of secondary organ function, enabling destination therapy.

Should we operate on patients with acute type A aortic dissection who present with cardiopulmonary resuscitation?

OBJECTIVES: Acute aortic dissection type A (AADA) is a life-threatening medical emergency. Emergent surgical repair is the gold standard but mortality remains high. Mortality is even higher in patients who arrive at the hospital in poor condition, especially after cardiopulmonary resuscitation (CPR). This study was designed to analyse the outcome of patients who underwent surgery for AADA and who require preoperative CPR. METHODS: Between 2000 and 2023, 810 patients underwent emergent surgery for AADA at our centre. Of these, 63 had preoperative CPR. We performed a retrospective analysis with follow-up. RESULTS: Mean age was 64 ± 13 years and 37 (59%) patients were male. Further, 50 (79%) patients had preoperative intubation, and 54 (86%) had pericardial effusion. Twenty-four (38%) patients had out-of-hospital CPR, 19 (30%) required CPR in hospital and 20 (32%) needed CPR in the operating room. Successful CPR with return of spontaneous circulation was achieved in 41 (65%) patients, and 22 (35%) underwent emergent surgery under ongoing CPR. The median time of CPR was 10 (interquartile range 12) min, and the median time from onset of symptoms to start of the operation was 5.5 (interquartile range 4.8) h. The majority of patients underwent ascending aortic replacement with hemiarch repair (n = 37, 59%). Further, 26 (41%) patients underwent full root replacement. Another 15 (24%) patients underwent total arch repair with or without (frozen) elephant trunk repair. Postoperative stroke was present in 8 (13%) patients. The 30-day mortality was 29 (46%). The 30-day mortality of patients with preoperative intubation was not significantly higher (n = 15/28, 54%, P = 0.446). The 1-, 5- and 10-year survival rates of the entire group were 42, 39 and 36%. CONCLUSIONS: Early mortality for patients undergoing surgery for AADA with preoperative CPR is extremely high (almost 50%). However, this means that also ∼50% of patients benefit from surgery despite poor preoperative prognosis. Patients with preoperative intubation after CPR and unknown neurological condition should also undergo surgery. Patients who survive the initial operation for AADA have acceptable long-term survival. Emergent surgery should be offered for all patients with AADA regardless of the preoperative condition, even after CPR.

A Novel Artificial Coronary Plaque to Model Coronary Heart Disease.

BACKGROUND: Experimental coronary artery interventions are currently being performed on non-diseased blood vessels in healthy animals. To provide a more realistic pathoanatomical scenario for investigations on novel interventional and surgical therapies, we aimed to fabricate a stenotic lesion, mimicking the morphology and structure of a human atherosclerotic plaque. METHODS: In an interdisciplinary setting, we engineered a casting mold to create an atherosclerotic plaque with the dimensions to fit in a porcine coronary artery. Oscillatory rheology experiments took place along with long-term stability tests assessed by microscopic examination and weight monitoring. For the implantability in future in vivo setups, we performed a cytotoxicity assessment, inserted the plaque in resected pig hearts, and performed diagnostic imaging to visualize the plaque in its final position. RESULTS: The most promising composition consists of gelatin, cholesterol, phospholipids, hydroxyapatite, and fine-grained calcium carbonate. It can be inserted in the coronary artery of human-sized pig hearts, producing a local partial stenosis and interacting like the atherosclerotic plaque by stretching and shrinking with the vessel wall and surrounding tissue. CONCLUSION: This artificial atherosclerotic plaque model works as a simulating tool for future medical testing and could be crucial for further specified research on coronary artery disease and is going to help to provide information about the optimal interventional and surgical care of the disease.

Valve-sparing aortic root replacement using a straight tube graft (David I procedure).

OBJECTIVES: We present our 25-year experience with valve-sparing aortic root replacement using a straight tube graft (David-I). METHODS: From 1993 to 2019, 677 patients (median age, 56.0 years; range, 42-65) underwent the David-I procedure with a straight tube graft. A total of 24 different surgeons performed these operations. Marfan syndrome was present in 111 patients (16.4%), and bicuspid aortic valve was present in 71 patients (10.5%). Aortic root aneurysm was present in 544 patients (80.4%), and acute dissection was present in 133 patients (19.6%). RESULTS: Ministernotomy was used in 57 patients (8.4%). Additional cusp plasty was performed in 84 patients (12.4%). Concomitant procedures were coronary artery bypass grafting (n = 122, 18.0%), mitral valve surgery (n = 34, 5%), proximal arch replacement (n = 125, 18.4%), subtotal arch replacement (n = 43, 6.4%), and total arch replacement (n = 102, 15.1%). Overall in-hospital mortality was 4.0% (n = 27), and perioperative stroke occurred in 26 patients (3.8%). Postoperative echocardiography showed aortic insufficiency less than I° in 600 of 623 (96.3%). The 1-, 5-, 10-, 15-, and 20-year survivals were 97%, 92%, 79%, 68%, and 50%, respectively. The rates for freedom from aortic valve-related reoperation at 1, 5, 10, 15, and 20 years were 97%, 92%, 87%, 84%, and 80%, respectively. Multivariate Cox regression analysis identified age (odds ratio, 0.974; 95% confidence interval, 0.957-0.992; P = .004), senior surgeon (odds ratio, 0.546; 95% confidence interval, 0.305-0.979; P = .042), and residual postoperative aortic insufficiency (odds ratio, 4.864; 95% confidence interval, 1.124-21.052; P = .034) as independent risk factors for aortic valve-related reoperation. CONCLUSIONS: The aortic valve-sparing David-I procedure can be performed with very low perioperative morbidity and mortality. The short- and long-term results are excellent. The straight tube graft does not lead to increased leaflet erosion. This procedure is reproducible by multiple surgeons.

Features and risk factors of early intraluminal thrombus formation within the frozen elephant trunk stent graft.

OBJECTIVE: The frozen elephant trunk is a standard treatment method for aortic arch pathologies extending into the descending aorta. We previously described the phenomenon of early postoperative intraluminal thrombosis within the frozen elephant trunk. We investigated the features and predictors of intraluminal thrombosis. METHODS: A total of 281 patients (66% male, mean age 60 ± 12 years) underwent frozen elephant trunk implantation between May 2010 and November 2019. In 268 patients (95%), early postoperative computed tomography angiography was available to assess intraluminal thrombosis. RESULTS: The incidence of intraluminal thrombosis after frozen elephant trunk implantation was 8.2%. Intraluminal thrombosis was diagnosed early after the procedure (4.6 ± 2.9 days) and could be successfully treated with anticoagulation in 55% of patients. A total of 27% developed embolic complications. Mortality (27% vs 11%, P = .044) and morbidity were significantly higher in patients with intraluminal thrombosis. Our data showed a significant association of intraluminal thrombosis with prothrombotic medical conditions and anatomic slow flow features. The incidence of heparin-induced thrombopenia was higher in patients with intraluminal thrombosis (18% vs 3.3%, P = .011). Stent-graft diameter index, anticipated endoleak Ib, and degenerative aneurysm were significant independent predictors of intraluminal thrombosis. Therapeutic anticoagulation was a protective factor. Glomerular filtration rate, extracorporeal circulation time, postoperative rethoracotomy, and intraluminal thrombosis (odds ratio, 3.19, P = .047) were independent predictors of perioperative mortality. CONCLUSIONS: Intraluminal thrombosis is an underrecognized complication after frozen elephant trunk implantation. In patients with risk factors of intraluminal thrombosis indication for frozen elephant trunk should be carefully evaluated and postoperative anticoagulation considered. Early thoracic endovascular aortic repair extension should be considered in patients with intraluminal thrombosis to prevent embolic complications. Stent-graft designs should be improved to prevent intraluminal thrombosis after frozen elephant trunk implantation.

Preoperative pericardial hematoma in patients with acute type A aortic dissection (AAAD): Do we need an adjusted treatment?

OBJECTIVE: An acute type A aortic dissection (AAAD) is a critical emergency and remains one of the most challenging diseases in cardiothoracic surgery. The existence of a pericardial hematoma caused by an aortic rupture can dramatically reduce the chances of survival (Jerzewski and Kulik in J Card Surg 29(4):529-530, 2014; Mehta et al. in Circulation 105(2):200-206, 2002; Gilon et al. in Am J Cardiol 103(7):1029-1031, 2009; Isselbacher et al. in Circulation 90(5):2375-2378, 1994). We assessed the surgical outcome of a high-risk group of patients with AAAD and a pericardial hematoma. METHODS: In this study we included 430 Patients (67% male; median age: 64 years) who received surgical treatment between January 2000 and January 2018 at our facility for acute aortic dissection DeBakey type I. We divided the cohort in two groups: Group A consisted of high-risk patients with a pericardial hematoma (n = 162) and Group B of patients without pericardial hematoma (n = 268). RESULTS: Patients with a preoperative pericardial hematoma had a significantly higher requirement for preoperative mechanical resuscitation (A: 21%; B: 1.5%; P: < 0.001) and were relevantly more frequently admitted to the operation theater with an intubated status (A: 19.8%; B: 8.6%; P: < 0.001). The incidence of visceral malperfusion differed significantly between both groups (A. 11.7%, B. 6:0%; P: 0.034). Limited aortic arch repair (proximal aortic arch replacement) was preferred in the high-risk group (A: 51.9%; B: 40.3%; P: 0.020). However, survival time was generally reduced in these patients (A: 7.5 y; B: 9.9 y). CONCLUSION: AAAD patients with preoperative pericardial hematoma present themselves in potentially lethal conditions, with a significantly higher rate of visceral malperfusion. Despite the existence of this risk factor, a limited arch repair was favored. We have proven that cardiac compression is associated with preoperative intubation and mechanical resuscitation. Patients with pericardial hematoma must be further evaluated for preoperative pericardial drainage. In the event of long transfer times to an aortic center a slow drainage should be discussed to prevent early mortality.

Stabilizing A Vascularized Autologous Matrix with Flexible Magnesium Scaffolds to Reconstruct Dysfunctional Left Ventricular Myocardium in a Large-Animal Feasibility Study.

The surgical reconstruction of dysfunctional myocardium is necessary for patients with severe heart failure. Autologous biomaterials, such as vascularized patch materials, have a regenerative potential due to in vivo remodeling. However, additional temporary mechanical stabilization of the biomaterials is required to prevent aneurysms or rupture. Degradable magnesium scaffolds could prevent these life-threatening risks. A left ventricular transmural defect was reconstructed in minipigs with a piece of the autologous stomach. Geometrically adaptable and degradable scaffolds made of magnesium alloy LA63 were affixed on the epicardium to stabilize the stomach tissue. The degradation of the magnesium structures, their biocompatibility, physiological remodeling of the stomach, and the heart's function were examined six months after the procedure via MRI (Magnetic Resonance Imaging), angiography, µ-CT, and light microscopy. All animals survived the surgery. Stable physiological integration of the stomach patch could be detected. No ruptures of the grafts occurred. The magnesium scaffolds showed good biocompatibility. Regenerative surgical approaches for treating severe heart failure are a promising therapeutic alternative to the currently available, far from optimal options. The temporary mechanical stabilization of viable, vascularized grafts facilitates their applicability in clinical scenarios.

Onset of pain to surgery time in acute aortic dissections type A: a mandatory factor for evaluating surgical results?

Objective: An acute aortic dissection type A (AADA) is a rare but life-threatening event. The mortality rate ranges between 18% to 28% and mortality is often within the first 24 h and up to 1%-2% per hour. Although the onset of pain to surgery time has not been a relevant factor in terms of research in the field of AADA, we hypothesize that a patient's preoperative conditions depend on the length of this time. Methods: Between January 2000 and January 2018, 430 patients received surgical treatment for acute aortic dissection DeBakey type I at our tertiary referral hospital. In 11 patients, the exact time point of initial onset of pain was retrospectively not detectable. Accordingly, a total of 419 patients were included in the study. The cohort was categorized into two groups: Group A with an onset of pain to surgery time < 6 h (n = 211) and Group B > 6 h (n = 208), respectively. Results: Median age was 63.5 years (y) ((IQR: 53.3-71.4 y); (67.5% male)). Preoperative conditions differed significantly between the cohorts. Differences were detected in terms of malperfusion (A: 39.3%; B: 23.6%; P: 0.001), neurological symptoms (A: 24.2%; B: 15.4%; P: 0.024), and the dissection of supra-aortic arteries (A: 25.1%; B: 16.8%; P: 0.037). In particular, cerebral malperfusion (A 15.2%: B: 8.2%; P: 0.026) and limb malperfusion (A: 18%, B: 10.1%; P: 0.020) were significantly increased in Group A. Furthermore, Group A showed a decreased median survival time (A: 1,359.0 d; B: 2,247.5 d; P: 0.001), extended ventilation time (A: 53.0 h; B: 44.0 h; P: 0.249) and higher 30-day mortality rate (A: 25.1%; B: 17.3%; P: 0.051). Conclusions: Patients with a short onset of pain to surgery time in cases of AADA present themselves not only with more severe preoperative symptoms but are also the more compromised cohort. Despite early presentation and emergency aortic repair, these patients show increased chances of early mortality. The "onset of pain to surgery time" should become a mandatory factor when making comparable surgical evaluations in the field of AADA.

Combination of Bacteriophages and Antibiotics for Prevention of Vascular Graft Infections-An In Vitro Study.

(1) Background: Implant-associated bacterial infections are usually hard to treat conservatively due to the resistance and tolerance of the pathogens to conventional antimicrobial therapy. Bacterial colonization of vascular grafts may lead to life-threatening conditions such as sepsis. The objective of this study is to evaluate whether conventional antibiotics and bacteriophages can reliably prevent the bacterial colonization of vascular grafts. (2) Methods: Gram-positive and Gram-negative bacterial infections were simulated on samples of woven PET gelatin-impregnated grafts using Staphylococcus aureus and Escherichia coli strains, respectively. The ability to prevent colonization was evaluated for a mixture of broad-spectrum antibiotics, for strictly lytic species-specific bacteriophage strains, and for a combination of both. All the antimicrobial agents were conventionally tested in order to prove the sensitivity of the used bacterial strains. Furthermore, the substances were used in a liquid form or in combination with a fibrin glue. (3) Results: Despite their strictly lytic nature, the application of bacteriophages alone was not enough to protect the graft samples from both bacteria. The singular application of antibiotics, both with and without fibrin glue, showed a protective effect against S. aureus (0 CFU/cm2), but was not sufficient against E. coli without fibrin glue (M = 7.18 × 104 CFU/cm2). In contrast, the application of a combination of antibiotics and phages showed complete eradication of both bacteria after a single inoculation. The fibrin glue hydrogel provided an increased protection against repetitive exposure to S. aureus (p = 0.05). (4) Conclusions: The application of antibacterial combinations of antibiotics and bacteriophages is an effective approach to the prevention of bacteria-induced vascular graft infections in clinical settings.

Acute Aortic Dissection Type A in Younger Patients (< 60 Years Old) - Does Full Arch Replacement Provide Benefits Compared to Limited Approach?

INTRODUCTION: Acute aortic dissection Stanford type A (AADA) is a surgical emergency associated with high morbidity and mortality. Although surgical management has improved, the optimal therapy is a matter of debate. Different surgical strategies have been proposed for patients under 60 years old. This paper evaluates the postoperative outcome and the need for secondary aortic operation after a limited surgical approach (proximal arch replacement) vs. extended arch repair. METHODS: Between January 2000 and January 2018, 530 patients received surgical treatment for AADA at our hospital; 182 were under 60 years old and were enrolled in this study - Group A (n=68), limited arch repair (proximal arch replacement), and group B (n=114), extended arch repair (> proximal arch replacement). RESULTS: More pericardial tamponade (P=0.005) and preoperative mechanical resuscitation (P=0.014) were seen in Group A. More need for renal replacement therapy (P=0.047) was seen in the full arch group. Mechanical ventilation time (P=0.022) and intensive care unit stay (P<0.001) were shorter in the limited repair group. Thirty-day mortality was comparable (P=0.117). New onset of postoperative stroke was comparable (Group A four patients [5.9%] vs. Group B 15 patients [13.2%]; P=0.120). Long-term follow-up did not differ significantly for secondary aortic surgery. CONCLUSION: Even though young patients received only limited arch repair, the outcome was comparable. Full-arch replacement was not beneficial in the long-time follow-up. A limited approach is justified in the cohort of young AADA patients. Exemptions, like known Marfan syndrome and the presence of an intimal tear in the arch, should be considered.

Frozen elephant trunk in acute aortic type a dissection: risk analysis of concomitant root replacement.

OBJECTIVES: To analyse whether full root replacement increases perioperative risks in patients who undergo frozen elephant trunk for acute aortic dissection. METHODS: Between March 2013 and December 2019, 115 patients underwent emergency frozen elephant trunk for acute dissection. Patients without root replacement were assigned to group A, while patients with concomitant full root replacement to group B. RESULTS: Mean age was 50.8 (12.5) years and 85 (73.9%) patients were male. Preoperative malperfusion was present in 49 (42.6%) patients. In group B, 27 (41.5%) patients received composite root replacement and 38 (33.0%) aortic valve-sparing David procedure. Cardiopulmonary-bypass and cross-clamp times were 252.5 (208.5-293.0) and 96.0 (40.5-148.0) min in group A, and 310.0 (274.0-346.5) and 121.0 (89.0-182.0) in group B (P < 0.001). Continuous myocardial perfusion was used in 40 (80.0%) patients of group A and 59 (90.8%) of group B (P = 0.098). Disabling stroke was present in 10 (20.0%) patients in group A and 12 (18.5%) in group B (P = 0.835). Thirty-day mortality was 12.0% (n = 6) in group A and 9.2% (n = 6) in group B (P = 0.630). The 1- and 5-year survival rates were 80% and 62% in group A, and 81% and 79% in group B. Logistic regression analysis identified age (odds ratio = 1.117, 95% confidence interval = 1.004-1.242, P = 0.041), cardiopulmonary-bypass time (odds ratio = 1.012, 95% confidence interval = 1.001-1.022, P = 0.029) and abdominal malperfusion (odds ratio = 17.394, 95% confidence interval = 2.030-149.013, P = 0.009) to be associated with 30-day mortality. CONCLUSIONS: Full root replacement does not increase the perioperative risk in patients who undergo frozen elephant trunk for acute dissection. Careful patient selection is important for such complex procedures. Continuous myocardial perfusion can help reducing the risk for intraoperative complications during such complex operations.

Is aortic valve-sparing root reimplantation (David-I) justified in cardiac redo surgery?

OBJECTIVES: Aortic valve-sparing root reimplantation (AVSRR) is a complex procedure, which offers the benefit of preserving the native aortic valve. Cardiac redo surgery is complex and time-consuming, and it is not known if David procedure is safe or beneficial in this context. METHODS: Between 1993 and 2019, we performed a total of 544 elective AVSRR operations at our centre. Patients were assigned to either group A (n = 30, redo) or group B (n = 514, first-time sternotomy). RESULTS: Aortic cross-clamp time was higher in the redo group (173[62] vs 125[31], P < 0.001). Cardiopulmonary bypass time was higher in the redo group as well (250[78] vs 179[51], P < 0.001). There were significantly more concomitant total arch replacements in the redo group (43.3% vs 5.8%, P < 0.001) using the 'beating heart' technique (20.0% vs 1.9%, P < 0.001). In-hospital mortality was comparable in both groups (3.3% vs 1.8%, P = 0.44). The rates for perioperative complications in terms of permanent neurological deficit and rethoracotomy were comparable between the 2 groups, too. Follow-up was complete for 99.6% of all patients and comprised a total of 584 patient-years. The 1-, 5-, 10- and 15-year survival rates were 90%, 81%, 60% and 55%, in group A (redo) and 96%, 90%, 78% and 67% in group B (native, P = 0.16), respectively. The rates for freedom from valve-related reoperation at 1, 5, 10 and 15 years after initial surgery were 96%, 92%, 92% and 92% in group A (redo) and 97%, 92%, 87% and 84% in group B (native, P = 0.52), respectively. CONCLUSIONS: Despite significantly more concomitant total arch replacements in the redo group, early mortality was comparable in both groups. We conclude that AVSRR can be performed in redo cardiac surgery without compromising the early postoperative outcome. Careful patient assessment and selection are mandatory when evaluating patients with a history of previous cardiac surgery for David procedure.

Single-center experience with thoracoabdominal aortic replacement in patients with Marfan syndrome.

Objectives: Patients with Marfan syndrome are usually not suitable for endovascular repair of the thoracoabdominal aorta. This study was designed to analyze our center's experience with open surgical thoracoabdominal aortic replacement in Marfan patients. Methods: This was a retrospective study with prospective follow-up. Between January 1995 and September 2021, a total of 648 patients underwent thoracoabdominal aortic replacement at our center. Of these, 60 had Marfan syndrome and were included in this study. Results: The mean age was 39.5 ± 10.7 years, and 36 (60%) were male. Ten (17%) had aortic aneurysm, 4 (7%) acute/subacute dissection, and 46 (77%) chronic dissection. Patients presented with the following extent of aortic disease according to the Crawford classification: I-17 (28%), II-18 (30%), III-22 (37%), IV-2 (3%), and V-1 (2%). The mean cardiopulmonary bypass time was 173.9 ± 84.7 minutes. Four (7%) patients required stent graft extraction. Postoperatively, 5 (8%) patients required rethoracotomy and 6 (10%) tracheostomy. One (1.7%) patient had permanent paraplegia and 2 (3%) permanent paraparesis. Two (3%) patients had stroke. One (1.7%) patient was discharged with dialysis. The 30-day mortality was 3% (n = 2). Median follow-up time was 21.5 (range, 9.4-33.6) years. The 1-, 5-, and 10-year survival rate was 87%, 80%, and 68%, respectively. There were 16 aortic reinterventions in 9 patients during follow-up. Conclusions: Thoracoabdominal aortic replacement remains a complex procedure but can be done extremely safely in Marfan patients. Perioperative mortality rates are very low, and the long-term outcomes are enduring. Because endovascular aortic repair is not recommended for patients with connective tissue disease, open surgery remains an important cornerstone of therapy.

Valve-sparing David procedure via minimally invasive access does not compromise outcome.

Objectives: Aortic valve sparing-aortic root replacement (David procedure) has not been routinely performed via minimally invasive access due to its complexity. We compared our results of elective David procedure via minimally invasive access to those via a full sternotomy. Methods: Between 1993 and 2019, a total of 732 patients underwent a valve sparing root replacement (David) procedure. Out of these, 220 patients underwent elective David-I procedure (isolated) without any other concomitant procedures at our center. Patients were assigned to either group A (n = 42, mini-access) or group B (n = 178, full sternotomy). Results: Cardiopulmonary bypass time were 188.5 ± 35.4 min in group A and 149.0 (135.5-167.5) in group B (p < 0.001). Aortic cross-clamp time were 126.2 ± 27.2 min in group A and 110.0 (97.0-126.0) in group B (p < 0.001). Post-operative echocardiography showed aortic insufficiency ≤ I° in 41 (100%) patients of group A and 155 (95%) of group B. In-hospital mortality was 2.4% (n = 1) in group A and 0% (n = 0) in group B (p = 0.191). Perioperative stroke occurred in 1 (2.4%) patient of group A and 2 (1.1%) patients of group B (p = 0.483). Reexploration for bleeding was necessary in 4 (9.5%) patients of group A and 7 (3.9%) of group B (p = 0.232). Follow-up was complete for 98% of all patients. The 1-, 2-, 4-, and 6-year survival rates were: 97, 97, 97, and 97%, in group A (mini-access) and 99, 96, 95, and 92% in group B (full sternotomy), respectively. The rates for freedom from valve-related re-operation at 1, 2, 4, and 6 years after initial surgery were: 97, 95, 95, and 84% in group A and 97, 95, 91, and 90% in group B, respectively. Conclusion: Early post-operative results after David procedure via minimally invasive access are comparable to conventional full sternotomy. Meticulous attention to hemostasis is a critical factor during minimally access David procedures. Long-term outcome including the durability of the reimplanted aortic valve seems to be comparable, too.

Ex-Vivo Preservation with the Organ Care System in High Risk Heart Transplantation.

OBJECTIVE: Ex vivo organ perfusion is an advanced preservation technique that allows graft assessment and extended ex situ intervals. We hypothesized that its properties might be especially beneficial for high-risk recipients and/or donors with extended criteria. METHODS: We reviewed the outcomes of 119 consecutive heart transplant patients, which were divided into two groups: A (OCS) vs. B (conventional). Ex vivo organ perfusion was performed using the Organ Care System (OCS). Indications for OCS-usage were expected ischemic time of >4 h or >2 h plus given extended donor criteria. RESULTS: Both groups included mostly redo cases (A: 89.7% vs. B: 78.4%; p = 0.121). Incidences of donors with previous cardiac arrest (%) (A: 32.4 vs. B: 22.2; p < 0.05) or LV-hypertrophy (%) (A: 19.1 vs. B: 8.3; p = 0.119) were also increased in Group A. Ex situ time (min) was significantly longer in Group A (A: 381 (74) vs. B: 228 (43); p < 0.05). Ventilation time (days) (A: 10.0 (19.9) vs. B: 24.3 (43.2); p = 0.057), postoperative need for ECLS (%) (A: 25.0 vs. B: 39.2; p = 0.112) and postoperative dialysis (chronic) (%) (A: 4.4 vs. B: 27.5; p < 0.001) were numerically better in the OCS group, without any difference in the occurrence of early graft rejection. The 30-d-survival (A: 92.4% vs. B: 90.2%; p = 0.745) and mid-term survival were statistically not different between both groups. CONCLUSIONS: OCS heart allowed safe transplantation of surgically complex recipients with excellent one-year outcomes, despite long preservation times and unfavourable donor characteristics. Furthermore, we observed trends towards decreased ventilation times and fewer ECLS treatments. In times of reduced organ availability and increasing recipient complexity, OCS heart is a valuable instrument that enables otherwise infeasible allocations and contributes to increase surgical safety.