Minimally invasive extracorporeal circulation versus conventional cardiopulmonary bypass in patients undergoing cardiac surgery (MiECS): Rationale and design of a multicentre randomised trial.

INTRODUCTION: The ultimate answer to the question whether minimal invasive extracorporeal circulation (MiECC) represents the optimal perfusion technique in contemporary clinical practice remains elusive. The present study is a real-world study that focuses on specific perfusion-related clinical outcomes after cardiac surgery that could potentially be favourably affected by MiECC and thereby influence the future clinical practice. METHODS: The MiECS study is an international, multi-centre, two-arm randomized controlled trial. Patients undergoing elective or urgent coronary artery bypass grafting (CABG), aortic valve replacement (AVR) or combined procedure (CABG + AVR) using extracorporeal circulation will be randomized to MiECC or contemporary conventional cardiopulmonary bypass (cCPB). Use of optimized conventional circuits as controls is acceptable. The study design includes a range of features to prevent bias and is registered at clinicaltrials.gov (NCT05487612). RESULTS: The primary outcome is a composite of postoperative serious adverse events that could be related to perfusion technique occurring up to 30 days postoperatively. Secondary outcomes include use of blood products, ICU and hospital length of stay (30 days) as well as health-related quality of life (30 and 90 days). CONCLUSIONS: The MiECS trial has been designed to overcome perceived limitation of previous trials of MiECC. Results of the proposed study could affect current perfusion practice towards advancement of patient care.

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

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

Individualized heparin monitoring and management reduces protamine requirements in cardiac surgery on minimal invasive extracorporeal circulation; A prospective randomized study.

INTRODUCTION: Individualized heparin and protamine management is increasingly used as a strategy to reduce coagulation activation and bleeding complications. While it is associated with increased heparin requirements during Cardiopulmonary Bypass (CPB), the impact on protamine administration remains controversial. We aim to investigate the effect of heparin level-guided monitoring on protamine dosing during cardiac surgery where low-anticoagulation protocols are implemented. METHODS: This is a prospective, randomized, controlled trial. A total of 132 patients undergoing elective full-spectrum cardiac surgery with Minimal Invasive Extracorporeal Circulation (MiECC) were recruited. All patients were managed by the same anaesthetic, surgical and perfusion team. Patients were randomly allocated in two groups; the individualized heparin-protamine titration (IHPT) group and the conventional heparinization and reversal group by using ACT (cACT) with a 0.75:1, protamine: heparin ratio. Titration was accomplished with the Hepcon HMS Plus (Medtronic, Minneapolis, MN) system. The primary outcome of the study was the total protamine dose used. Secondary outcomes comprised of the total heparin dose, the percentage of patients achieving target ACT, 24-h transfusion requirements, postoperative bleeding, duration of mechanical ventilation, major morbidity and length of hospital stay. Patients in each group were divided in two subgroups according to the target ACT; those operated for coronary artery bypass grafting (CABG) using a target ACT >300 s and the rest (non-CABG) patients operated with a target ACT >400 s, respectively. RESULTS: Protamine requirements were significantly reduced when IHPT was implemented; CABG (118 ± 24 mg vs 163 ± 61 mg; p < 0.001) and non-CABG cases (151 ± 46 mg vs 197 ± 45 mg; p < 0.001). Moreover, heparin requirements were significantly higher in the non-CABG subgroup managed with IHPT (34,539 ± 7658 IU vs 29,893 ± 9037 IU; p = 0.02). In overall, no significant differences were detected with respect to postoperative bleeding, transfusion of RBC or other blood products. CONCLUSIONS: Individualized heparin monitoring and management reduces protamine requirements in cardiac surgery with MiECC implementing reduced anticoagulation strategy. TRIAL REGISTRATION: clinicaltrials.gov; NCT04215588.

2021 MiECTiS focused update on the 2016 position paper for the use of minimal invasive extracorporeal circulation in cardiac surgery.

The landmark 2016 Minimal Invasive Extracorporeal Technologies International Society (MiECTiS) position paper promoted the creation of a common language between cardiac surgeons, anesthesiologists and perfusionists which led to the development of a stable framework that paved the way for the advancement of minimal invasive perfusion and related technologies. The current expert consensus document offers an update in areas for which new evidence has emerged. In the light of published literature, modular minimal invasive extracorporeal circulation (MiECC) has been established as a safe and effective perfusion technique that increases biocompatibility and ultimately ensures perfusion safety in all adult cardiac surgical procedures, including re-operations, aortic arch and emergency surgery. Moreover, it was recognized that incorporation of MiECC strategies advances minimal invasive cardiac surgery (MICS) by combining reduced surgical trauma with minimal physiologic derangements. Minimal Invasive Extracorporeal Technologies International Society considers MiECC as a physiologically-based multidisciplinary strategy for performing cardiac surgery that is associated with significant evidence-based clinical benefit that has accrued over the years. Widespread adoption of this technology is thus strongly advocated to obtain additional healthcare benefit while advancing patient care.

Minimal invasive extracorporeal circulation preserves coagulation integrity.

INTRODUCTION: Coagulopathy after cardiac surgery is a serious multifactorial complication that results in postoperative bleeding requiring transfusion of red blood cells and procoagulant products. Use of cardiopulmonary bypass represents the major contributing factor affecting coagulation. We sought to prospectively investigate the effect of contemporary minimal invasive extracorporeal circulation (MiECC) on coagulation parameters using point-of-care (POC) rotational thromboelastometry and the relation to postoperative bleeding. METHODS: Patients undergoing elective cardiac surgery on MiECC were prospectively recruited. Anticoagulation strategy was based on individualized heparin management and heparin level-guided protamine titration. Rotational thromboelastometry testing was performed before induction of anesthesia and after aortic cross-clamp release. A strict POC-guided transfusion protocol was implemented. The primary endpoint was the assessment of viscoelastic properties of the coagulating blood at the end of surgery compared to preoperative values and the relation to postoperative bleeding and 24-hour transfusion requirements. RESULTS: Fifty patients were included in the study with a significant proportion having complex surgery. Thirteen patients (26%) required blood transfusion (mean rate: 0.5 ± 1 units per patient), 5/50 (10%) received coagulation factors while no patient received fresh frozen plasma, platelets or fibrinogen. Thromboelastometry analysis showed that the major derangement was CT EXTEM > 100 seconds in 28/50 (56%) and A10 EXTEM < 40 mm in one (2%) patient without clinical significance. Platelet function was preserved throughout surgery. A10-FIBTEM was found predictive of postoperative bleeding at 12 hours. CONCLUSIONS: MiECC preserves clot quality throughout surgery acting in both key determinants of clot strength; fibrinogen and platelets. This is clinically translated into minimal postoperative bleeding and restricted use of blood products and coagulation factors.

Modular minimally invasive extracorporeal circulation ensures perfusion safety and technical feasibility in cardiac surgery; a systematic review of the literature.

INTRODUCTION: Despite extensive evidence that shows clinical of superiority of MiECC, worldwide penetration remains low due to concerns regarding air handling and volume management in the context of a closed system. The purpose of this study is to thoroughly investigate perfusion safety and technical feasibility of performing all cardiac surgical procedures with modular (hybrid) MiECC, as experienced from the perfusionist's perspective. METHODS: We retrospectively reviewed perfusion charts of consecutive adult patients undergoing all types of elective, urgent, and emergency cardiac surgery under modular MiECC. The primary outcome measure was perfusion safety and technical feasibility, as evidenced in the need for conversion from a closed to an open circuit. A systematic review of the literature was conducted aiming to ultimately clarify whether there are any safety issues regarding MiECC technology. RESULTS: We challenged modular MiECC use in a series of 403 consecutive patients of whom a significant proportion (111/403; 28%) underwent complex surgery including reoperations (4%), emergency repair of acute type A aortic dissection and composite aortic surgery (1.7%). Technical success rate was 100%. Conversion to an open circuit was required in 18/396 patients (4.5%), excluding procedures performed under circulatory arrest. Open configuration accounted for 40% ± 21% of total procedural perfusion time and was related to significant hemodilution and increase in peak lactate levels. Systematic review revealed that safety of the procedure challenged originated from a single report, while no clinical adverse event related to MiECC was identified. CONCLUSIONS: Use of modular MiECC secures safety and ensures technical feasibility in all cardiac surgical procedures. It represents a type III active closed system, while its stand-by component is reserved for a small (<5%) proportion of procedures and for a partial procedural time. Thus, it eliminates any safety concern regarding air handling and volume management, while it overcomes any unexpected intraoperative scenario.

The left-sided aortic arch variants: prevalence meta-analysis of imaging studies.

PURPOSE: To estimate the prevalence of the left-sided aortic arch (LSAA) variants, and the effect of possible moderators on variants' detection. METHODS: A systematic online literature search was conducted. The pooled prevalence with 95% confidence intervals was estimated for the typical and atypical branching patterns to compare the overall proportions of different variants. Meta-regression analyses were performed to investigate the effect of the subjects' gender and geographical region, and the multidetector computed tomography (MDCT) scanner's technology on the estimated prevalence. RESULTS: In total, 18,075 cases from 23 imaging studies were included and 33 different LSAA variants were detected. The estimated heterogeneity was statistically significant. Based on the estimated prevalence, approximately 77% of the population is expected to have the typical branching anatomy with sequence brachiocephalic trunk-left common carotid artery-left subclavian artery, and 23% variant branching patterns. Approximately 71%, 23%, 2%, and 0.1% of the atypical populations are expected to have two, four, three, and five emerging branches, respectively. The meta-regression analyses showed that the number of detector rows of the MDCT scanner, and the subjects' geographical region are statistically significant moderators of the estimated prevalence. CONCLUSION: The current findings indicate that the prevalence of the LSAA variant branching anatomy is significantly affected by the subjects' geographical region and the MDCT scanner's technological improvement, with the advanced scanners to facilitate the detection of the aortic arch variants. However, due to the heterogeneity among studies, further research is required.

Minimal invasive extracorporeal circulation preserves platelet function after cardiac surgery: a prospective observational study.

INTRODUCTION: Cardiac surgery on conventional cardiopulmonary bypass induces a combination of thrombocytopenia and platelet dysfunction which is strongly related to postoperative bleeding. Minimal invasive extracorporeal circulation has been shown to preserve coagulation integrity, though effect on platelet function remains unclear. We aimed to prospectively investigate perioperative platelet function in a series of patients undergoing cardiac surgery on minimal invasive extracorporeal circulation using point-of-care testing. METHODS: A total of 57 patients undergoing elective cardiac surgery on minimal invasive extracorporeal circulation were prospectively recruited. Anticoagulation strategy was based on individualized heparin management and heparin level-guided protamine titration performed in all patients with a specialized point-of-care device (Hemostasis Management System - HMS Plus; Medtronic, Minneapolis, MN, USA). Platelet function was evaluated with impedance aggregometry using the ROTEM platelet (TEM International GmbH, Munich, Germany). ADPtest and TRAPtest values were assessed before surgery and after cardiopulmonary bypass. RESULTS: ADPtest value was preserved during surgery on minimal invasive extracorporeal circulation (58.2 ± 20 U vs. 53.6 ± 21 U; p = 0.1), while TRAPtest was found significantly increased (90 ± 27 U vs. 103 ± 38 U; p = 0.03). Postoperative ADPtest and TRAPtest values were inversely related to postoperative bleeding (correlation coefficient: -0.29; p = 0.03 for ADPtest and correlation coefficient: -0.28; p = 0.04 for TRAPtest). The preoperative use of P2Y12 inhibitors was identified as the only independent predictor of a low postoperative ADPtest value (OR = 15.3; p = 0.02). CONCLUSION: Cardiac surgery on minimal invasive extracorporeal circulation is a platelet preservation strategy, which contributes to the beneficial effect of minimal invasive extracorporeal circulation in coagulation integrity.

Quantification of Operational Learning in Minimal Invasive Extracorporeal Circulation.

Minimal invasive extracorporeal circulation (MiECC) has initiated important new efforts within science and technology towards a more physiologic perfusion. In this study, we aim to investigate the learning curve of our center regarding MiECC. We studied a series of 150 consecutive patients who underwent elective coronary artery bypass grafting by the same surgical team during the initial phase of MiECC application. Patients were randomly assigned into two groups. Group A (n = 75) included patients operated on MiECC, while group B (n = 75) included patients operated with conventional cardiopulmonary bypass (cCPB). The primary end-point of the study was to identify whether there is a learning curve when operating on MiECC. The following parameters were unrelated with increasing experience, even though the results favored MiECC use: reduced CPB duration (102.9 ± 25 vs. 122.2 ± 33 min, P <0.001), peak troponin release (0.07 ± 0.02 vs. 0.1 ± 0.04 ng/mL, P < 0.01), peak creatinine levels (0.97 ± 0.24 vs. 1.2 ± 0.3 mg/dL, P < 0.001), duration of mechanical ventilation (14.1 ± 7.2 vs. 36.9 ± 59.8 h, P < 0.01) and ICU stay (2.1 ± 0.7 vs. 4.4 ± 6.4 days, P < 0.01). However, need for intraoperative blood transfusion showed a trend towards a gradual decrease as experience with MiECC system was accumulating (R2 = 0.094, P = 0.007). Subsequently, operational learning applied to postoperative hematocrit and hemoglobin levels (R2 = 0.098, P = 0.006). We identified that advantages of MiECC technology in terms of reduced hemodilution and improved end-organ protection and clinical outcome are evident from the first patient. Optimal results are obtained with 50 cases; this refers mainly to significant reduction in the need for intraoperative blood transfusion. Teamwork from surgeons, anesthesiologists, and perfusionists is of paramount importance in order to maximize the clinical benefits from this technology.

A multidisciplinary perioperative strategy for attaining "more physiologic" cardiac surgery.

BACKGROUND: Cardiac surgery is, by definition, a "non-physiologic" intervention associated with systemic adverse effects. Despite advances in surgical technique, cardiopulmonary bypass (CPB) technology as well as anaesthesia management and patient care, there is still significant morbidity and subsequent mortality. AIM: We consider that the contemporary demand for further improving patient outcome mandates the upgrade from optimal perfusion during the procedure as the gold standard to the concept of a "more physiologic" cardiac surgery. Our policy is a multidisciplinary perioperative strategy based on goal-directed perfusion throughout surgery incorporating in-line monitoring. This translates to "prevent rather than correct" malperfusion through real-time adjustment rather than correction of derangement detected late by incremental evaluation. METHOD: The strategy is based on continuous monitoring of cardiac index, SvO2, DO2i, DO2i/VCO2i and rSO2. Data acquisition is followed by action when needed; this includes stepwise: transfusion, increase of cardiac output and initiation of inotropic/vasoactive support. Moreover, implementation of minimally invasive extracorporeal circulation (MiECC) is considered as a fundamental component of physiologic perfusion when on-CPB, providing improved circulatory support and end-organ protection. CONCLUSION: We consider that, with this strategy which establishes optimal perfusion perioperatively, we attain the goal of a "more physiologic" cardiac surgery.

Enhanced recovery after elective coronary revascularization surgery with minimal versus conventional extracorporeal circulation: a prospective randomized study.

OBJECTIVE: A minimal extracorporeal circulation (MECC) circuit integrates the advances in cardiopulmonary bypass (CPB) technology into a single circuit and is associated with improved short-term outcome. The aim of this study was to prospectively evaluate MECC compared with conventional CPB in facilitating fast-track recovery after elective coronary revascularization procedures. DESIGN: Prospective randomized study. SETTING: All patients scheduled for elective coronary artery surgery were evaluated, excluding those considered particularly high risk for fast-track failure. The fast-track protocol included careful preoperative patient selection, a fast-track anesthetic technique based on minimal administration of fentanyl, surgery at normothermia, early postoperative extubation in the cardiac recovery unit, and admission to the cardiothoracic ward within the first 24 hours postoperatively. PARTICIPANTS: One hundred twenty patients were assigned randomly into 2 groups (60 in each group). INTERVENTIONS: Group A included patients who were operated on using the MECC circuit, whereas patients in Group B underwent surgery on conventional CPB. MEASUREMENTS AND MAIN RESULTS: Incidence of fast-track recovery was significantly higher in patients undergoing MECC (25% v 6.7%, p = 0.006). MECC also was recognized as a strong independent predictor of early recovery, with an odds ratio of 3.8 (p = 0.011). Duration of mechanical ventilation and cardiac recovery unit stay were significantly lower in patients undergoing MECC together with the need for blood transfusion, duration of inotropic support, need for an intra-aortic balloon pump, and development of postoperative atrial fibrillation and renal failure. CONCLUSIONS: MECC promotes successful early recovery after elective coronary revascularization procedures, even in a nondedicated cardiac intensive care unit setting.

Successful high-risk percutaneous coronary intervention with the use of minimal extracorporeal circulation system.

Minimal extracorporeal circulation (MECC) represents a contemporary system which integrates several advances in cardiopulmonary bypass technology in a single circuit. We challenged the efficacy of the MECC system to support the circulation in elective high-risk percutaneous coronary intervention (PCI). A 78-year-old patient with complex coronary disease who would have been otherwise rejected for interventional therapy underwent PCI with rotablation on MECC support. The MECC system provided hemodynamic support at a flow of 1.8 L min(-1) m(-2) while perfusion pressure was kept at a minimum of 70 mm Hg. This allowed for successful angioplasty of the left main stem and a chronically occluded right coronary artery, which otherwise produced significant hemodynamic compromise. This case illustrates that mechanical circulatory support with the MECC system could provide a stable environment and a "safety net" for carrying out complex percutaneous coronary intervention in high-risk patients.

A modified two-port thoracoscopic technique versus axillary minithoracotomy for the treatment of recurrent spontaneous pneumothorax: a prospective randomized study.

BACKGROUND: Currently, most thoracic surgeons perform surgical pleurodesis for recurrent spontaneous pneumothorax (RSP) by video-assisted thoracic surgery (VATS). However, the superiority of VATS over axillary minithoracotomy is not been established in prospective studies to date. A modified two-port VATS technique and axillary minithoracotomy were prospectively evaluated for possible differences in the short- and long-term outcome for patients. METHODS: In this study, 66 consecutive patients underwent surgical pleurodesis for RSP through either a modified two-port VATS procedure (group A, 33 patients) or axillary minithoracotomy (group B, 33 patients). According to the study design (NCT01192217), the patients were randomly assigned to the two groups, which were similar in terms of age and body mass index. One-lung ventilation time, histology of the available lung parenchyma specimens, early postoperative complications, length of chest tube drainage and hospital stay, recurrence rate, and a score for patient satisfaction with treatment based on the sum of postoperative pain, dependent-arm mobilization, and return to full activity subscores were evaluated. The follow-up period varied from 3 to 53 months (median, 30 months). RESULTS: The one-lung ventilation and operating times were significantly longer (p < 0.001) in group A than in group B. The overall detection of blebs, bulla, or both was 51.5% in group A and 63.8% in group B. The recurrence rate, complication rate, postoperative chest tube drainage duration, postoperative hospital stay, and incidence of chronic pain did not differ between the two groups. The score for patient satisfaction with treatment was significantly higher in group A than in group B (p < 0.001) according the subscores for better dependent-arm mobilization and return to full activity. CONCLUSIONS: Axillary minithoracotomy and VATS are equally effective for the treatment of RSP, although the rate for resection of blebs, bulla, or both is higher with the axillary minithoracotomy procedure. Although VATS is more time consuming, it offers to the patient more satisfaction with treatment.

Hybrid approach of ventricular assist device and autologous bone marrow stem cells implantation in end-stage ischemic heart failure enhances myocardial reperfusion.

We challenge the hypothesis of enhanced myocardial reperfusion after implanting a left ventricular assist device together with bone marrow mononuclear stem cells in patients with end-stage ischemic cardiomyopathy. Irreversible myocardial loss observed in ischemic cardiomyopathy leads to progressive cardiac remodelling and dysfunction through a complex neurohormonal cascade. New generation assist devices promote myocardial recovery only in patients with dilated or peripartum cardiomyopathy. In the setting of diffuse myocardial ischemia not amenable to revascularization, native myocardial recovery has not been observed after implantation of an assist device as destination therapy. The hybrid approach of implanting autologous bone marrow stem cells during assist device implantation may eventually improve native cardiac function, which may be associated with a better prognosis eventually ameliorating the need for subsequent heart transplantation. The aforementioned hypothesis has to be tested with well-designed prospective multicentre studies.

Use of minimized extracorporeal circulation system in noncoronary and valve cardiac surgical procedures-a case series.

The aim of this report is to explore application of minimized cardiopulmonary bypass (CPB) circuits in areas of cardiac surgery other than coronary bypass grafting and aortic valve surgery. We report three cases operated under minimal extracorporeal circulation support. Replacement of the descending thoracic aorta was performed in two patients; one with a descending aortic aneurysm and one with pseudoaneurysm formation after previous coarctation repair. We have also implanted a left ventricular assist device for destination therapy. The minimized extracorporeal circulation system provides optimal circulatory support, while it is associated with reduced postoperative morbidity, minimizing the side effects from the use of CPB. Moreover, when off-pump technique is attempted, it can be used as a standby circuit connected to the patient so as to enhance safety of the procedure. Minimized extracorporeal circulation systems can be used with safety and efficacy in a wide range of cardiac surgeries including descending aorta pathology and assist device implantation.