Apostolos Deliopoulos

Use of minimal invasive extracorporeal circulation in cardiac surgery: principles, definitions and potential benefits. A position paper from the Minimal invasive Extra-Corporeal Technologies international Society (MiECTiS)

Minimal invasive extracorporeal circulation (MiECC) systems have initiated important efforts within science and technology to further improve the biocompatibility of cardiopulmonary bypass components to minimize the adverse effects and improve end-organ protection. The Minimal invasive Extra-Corporeal Technologies international Society was founded to create an international forum for the exchange of ideas on clinical application and research of minimal invasive extracorporeal circulation technology. The present work is a consensus document developed to standardize the terminology and the definition of minimal invasive extracorporeal circulation technology as well as to provide recommendations for the clinical practice. The goal of this manuscript is to promote the use of MiECC systems into clinical practice as a multidisciplinary strategy involving cardiac surgeons, anaesthesiologists and perfusionists.

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.

Haematological effects of minimized compared to conventional extracorporeal circulation after coronary revascularization procedures.

During the last decade, minimized extracorporeal circulation (MECC) systems have shown beneficial effects to the patients over the conventional cardiopulmonary bypass (CECC) circuits. This is a prospective randomized study of 99 patients who underwent coronary artery bypass grafting (CABG) surgery, evaluating the postoperative haematological effects of these systems. Less haemodilution (p=0.001) and markedly less haemolysis (p<0.001), as well as better preservation of the coagulation system integrity (p=0.01), favouring the MECC group, was found. As a clinical result, less bank blood requirements were noted and a quicker recovery, as far as mechanical ventilation support and ICU stay are concerned, was evident with the use of MECC systems. As a conclusion, minimized extracorporeal circulation systems may attenuate the adverse effects of conventional circuits on the haematological profile of patients undergoing CABG surgery.

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.

Modular minimally invasive extracorporeal circulation systems; can they become the standard practice for performing cardiac surgery?

Minimally invasive extracorporeal circulation (MiECC) has been developed in an attempt to integrate all advances in cardiopulmonary bypass technology in one closed circuit that shows improved biocompatibility and minimizes the systemic detrimental effects of CPB. Despite well-evidenced clinical advantages, penetration of MiECC technology into clinical practice is hampered by concerns raised by perfusionists and surgeons regarding air handling together with blood and volume management during CPB. We designed a modular MiECC circuit, bearing an accessory circuit for immediate transition to an open system that can be used in every adult cardiac surgical procedure, offering enhanced safety features. We challenged this modular circuit in a series of 50 consecutive patients. Our results showed that the modular AHEPA circuit design offers 100% technical success rate in a cohort of random, high-risk patients who underwent complex procedures, including reoperation and valve and aortic surgery, together with emergency cases. This pilot study applies to the real world and prompts for further evaluation of modular MiECC systems through multicentre trials.

Minimal extracorporeal circulation reduces the incidence of postoperative major adverse events after elective coronary artery bypass grafting in high-risk patients. A single-institutional prospective randomized study

Coronary artery bypass grafting (CABG) using minimal extracorporeal circulation (MECC) has been associated with an improved short-term clinical outcome compared to conventional extracorporeal circulation (CECC). The aim of this study was to evaluate the impact of MECC compared to CECC on postoperative major adverse events in high-risk patients undergoing elective coronary revascularization procedures. Two hundred patients undergoing elective CABG were randomized into two groups. In Group A (n=100), MECC was used while Group B (n=100) included patients who were operated on CECC. The incidence of postoperative major adverse events (myocardial infarction, renal failure, stroke, death) was the primary end-point of the study. MECC was associated with a 77% relative risk reduction in the incidence of major adverse events compared to CECC (p=0.004). The rate of major adverse events occurring in the high-risk patient subgroup (preoperative left ventricular ejection fraction ≤40%, age >65 years, EuroSCORE II >5) operated on with MECC was significantly lower in comparison to their CECC counterparts. Based on our results, cardiac centres should be encouraged to use MECC as the standard circuit when performing elective coronary procedures, even in a high-risk population.

Minimally invasive extracorporeal circulation improves quality of life after coronary artery bypass grafting

OBJECTIVES The effect on postoperative health-related quality of life (HRQoL) after coronary artery bypass grafting (CABG) surgery with conventional cardiopulmonary bypass (cCPB) and off-pump surgery has been investigated extensively; however, there are no studies focusing on HRQoL after surgery with minimally invasive extracorporeal circulation (MiECC). Therefore, we sought to prospectively investigate the effect of MiECC on postoperative HRQoL when compared with cCPB in patients undergoing CABG over a short-term (3-month) follow-up period. METHODS Sixty patients scheduled for elective CABG surgery were randomly assigned into two groups: those who had surgery on MiECC system (n = 30) and those who underwent CABG using cCPB (n = 30). Quality-of-life assessment was performed preoperatively (baseline-T0), at first postoperative month (T1) and at 3-month follow-up (T3). The RAND SF-36 scale was used for data collection, which included both sociodemographic and clinical characteristics of patients. The primary outcome of the study was quantitative measurement of postoperative HRQoL at 3-month follow-up. RESULTS Both groups were balanced in terms of demographic, socio-economic and operative characteristics. At 3-month follow-up, mean SF-36 component and summary scores in each group were higher in absolute values than the respective mean baseline scores, apart from role-physical score in patients operated with cCPB. Patients operated on MiECC showed uniformly significantly higher values in all individual and summary domains, whereas patients operated on cCPB showed significant improvement in 6/8 individual domains. Patients operated on MiECC showed a more pronounced increase in SF-36 individual domain scores from the first to the third postoperative month when compared with cCPB, which was statistically significant regarding physical functioning (P = 0.001), role-physical (P < 0.001), vitality (P = 0.01) and role-emotional (P = 0.004). This resulted in a significant improvement in physical (P = 0.002) and mental (P = 0.01) summary scores. CONCLUSIONS The current study proves that MiECC significantly improves HRQoL after coronary surgery compared with cCPB. This finding, combined with results from large-scale studies showing superior clinical outcomes from its use, enhances the role of MiECC as a dominant technique in coronary revascularization surgery.

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.

Use of miniaturized extracorporeal circulation for implanting left ventricular assist devices in high-risk end-stage heart failure patients

Background Miniaturized extracorporeal circulation (MECC) has been implemented in clinical practice for the last decade with superior results regarding postoperative morbidity and mortality mainly in coronary procedures. We challenged this technique in high-risk patients with end-stage heart failure undergoing left ventricular assist device (LVAD) implantation. Methods Four patients with end-stage ischemic heart failure were included in this study. All patients were inotrope dependent (INTERMACS class 2) and their preoperative evaluation considered them to be high-risk for developing postoperative right ventricular failure. Hence, optimization of right ventricular function was performed preoperatively following a protocol based on intermittent administration of doses of levosimendan. Two Jarvik 2000 and two HeartWare LVADs were implanted on beating heart using MECC system. Surgical strategy included retrograde autologous priming of the circuit and avoidance of administering cardioplegia. Results