Background: The CardioWest temporary total artificial heart (TAH-t) replaces both native ventricles of the heart and is more beneficial for a select group of patients than most other typical ventricular assist devices (VADs). This review will expand on the current literature and highlight the chronology of this device. The CardioWest TAH-t has been implanted in over 715 patients at 30 multiple institutional centers worldwide as a bridge-to-transplant (BTT) since 1993. The mechanical flow dynamics of the device are manufactured and designed differently from other traditional VADs, allowing increased outputs and normal filling pressures, allowing for sufficient organ and tissue perfusion and dramatic recoveries, allowing patients to return to an almost normal quality of life. Results: There was a 79% survival to transplant achievement in the protocol group who received the TAH-t versus a 46% in the control group (P < 0.001). Furthermore, there was a 70% survival rate at one year in the protocol group versus 31% in the control group (P < 0.001). The one- and five-year survival rates after transplantation were 69% and 34%, respectively, in the control group and 86% and 64%, respectively, in the protocol group. Conclusion: It is evident that the advancement of modern engineering and medicine has made way for a reliable and durable device that provides a promising future in the field of end-stage heart failure.

Attenuated inflammatory response and decreased platelet activation have been claimed repeatedly when biocompatible circuits are used for cardiopulmonary bypass. We evaluated five Health Canada approved biocompatible circuit coatings (BCC) against an un-coated control group to determine their effectiveness in improving post-operative outcomes.

Patients were assigned to the Control group or one of the 5 coated circuit groups: 40 Control; 33 Trillium; 32 Phisio; 34 Bioline; 33 X; and 11 GBS. Measured outcomes included: ventilator time; ICU time; post-operative chest tube drainage and transfusion volume; high sensitivity C-reactive protein (hsCRP); tau protein; and pre- and 72-hour post-operative anti-saccadic eye movement test comparisons.

Results: 183 patients were enlisted into the study. One arm of the study (GBS) was abandoned after 11 patients on account of inconsistent pressure excursions within the oxygenator and the excessive consumption of platelets necessitating transfusion. Patients in the X-coated group had significantly longer ventilator and intensive care unit (ICU) time compared to the three remaining coated circuit study groups. Though not significant, patients in the X group also demonstrated the highest post-operative chest tube losses, the most platelet transfusions, the highest tau protein levels and the lowest post-operative anti-saccadic eye movement test (ASEMT) results compared to the three remaining coated groups. The patients in the Trillium, Bioline and Phisio groups showed an improvement in ventilator and ICU time relative to the Control group. The diabetic patients in the Trillium, Bioline and Phisio groups showed an improvement in bleeding relative to the diabetic patients in the Control group.

Conclusion: We compared all 5 coated circuits approved for clinical use in Canada against an uncoated control circuit. Three of the 5 coated circuits (Trillium, Phisio and Bioline BCC) were found to improve ventilator and ICU time compared to Control. Further studies are indicated to validate these results and their impact upon approval criteria, purchasing choices and safe clinical practice, especially as applied to higher risk diabetic patients.

Background: Accurate information about different blood parameters is essential in maintaining haemodynamics, perfusion and gas exchange during cardiopulmonary bypass (CPB). For this purpose, precise, accurate and continuous measurement and monitoring, preferably visually available, is needed. The objective of this clinical study was to compare the newly developed continuous in-line blood parameter monitoring system (CIBPMS) BMU 40 with a reference laboratory analyser with regards to the precision and accuracy of blood parameter measurement.

Methods: Thirty adult patients underwent elective cardiac surgery, CPB and mild hypothermia (32°C). At five predetermined time points (S1 – S5) arterial and venous blood samples were analysed using the BMU 40 for five different parameters (PaO₂(37°C), PaO₂(act), SvO₂, Hb(ven) and Hct(ven)) and these results were compared to the gold standard laboratory analyser, the ABL 700.

Result: A total of 150 paired blood samples were included to compare means, to analyse correlation, and to calculate measures of bias, precision, limits of agreement and 95% confidence intervals. Results revealed good agreement between the two devices for all parameters. Bias ± precision of S2 – S5 PaO₂(37°C) were: 2.17 ± 9.61; PaO₂(act) 2.58 ± 9.54; SvO₂ –1.44 ± 2.35; Hb(ven) 0.01 ± 0.42; Hct(ven) 0.04 ± 1.29. Statistically significant differences were detected for SvO₂ (p<0.00001) at S1. Correlations after this first time point (S1) improved following an in vivo calibration.

Conclusion: The BMU 40 is a precise, accurate and reliable continuous in-line blood parameter measuring system that can easily be used within a standard CPB setup. However, present data suggest an in vivo calibration of the BMU 40 should be performed.

A 27-year-old, G₃P₂A₀ female with acute Staph aureus (SA) endocarditis successfully underwent CPB-assisted aortic valve replacement with a bioprosthetic aortic valve at 22 weeks’ gestation. This patient’s presentation of acute endocarditis complicated by septic shock, congestive heart failure, severe aortic insufficiency, multiple septic embolic events and borderline renal failure appeared on the daunting background of chronic heavy tobacco usage, hepatitis C positivity, longterm IV drug abuse and a pregnancy into its twenty-second week. Optimal treatment strategies implemented for both mother and fetus throughout the perioperative period contributed to a successful outcome for both.

Twenty (20) CPB-circuits were randomized to a CO₂ group or a control group. In the CO₂ group, each circuit was flushed with CO₂ (10L/min) at the top of the venous reservoir for 5 minutes, after which priming fluid was added without interruption of the CO₂ inflow. Control group circuits were not flushed and contained air. A perfusionist, blinded to the study, started the pump (5L/min), ventilated the oxygenator (3L O₂/min), and knocked on the oxygenator 20 times during the first and 14^th minutes. Arterial line microemboli counts were registered with a Doppler for 15 minutes. In both groups, the median number of microemboli was highest during the first minute, 380.5 (288.75/422.25, 25^th/75^th percentile) counts in the control group versus 264.5 (171.75/422.25) counts in the CO₂ group (p=0.01). Throughout the experiment, the median microembolic count minute by minute in the CO₂ group remained lower (p≤0 .004) than in the control group. Knocking on the reservoir (14^th minute) increased the microemboli counts in both groups (p<0.01). The median values during the 15^th minute were 15.5 and 0.5 in the control and the CO₂ groups, respectively, which were 9% (15.5/173) and 0.5% (0.5/87), respectively, of the values registered after 14 minutes. In conclusion, CO₂ flushing of the empty circuit decreases the number of gaseous emboli in the prime compared with a conventional circuit that contains air before being primed with fluid. Knocking of the oxygenator releases gaseous emboli and the duration of re-circulating the circuit with prime influences the number of microemboli.

This study was to compare the impact of different biocompatible coated circuits on inflammatory response and oxidative stress induced during cardiopulmonary bypass (CPB). Seventy-eight patients undergoing elective coronary artery bypass grafting (CABG) with CPB were randomly assigned to five groups with different biocompatible coated circuits: Trillium, Bioline, Phosphorylcholine, Polymethoxyethyl acrylate (PMEA), and the uncoated control group. Blood was drawn at three different time points: before CPB, 6 and 72 hours post CPB. Unlike the Trillium group, serum levels of TNF- in the Bioline and Phosphorylcholine groups significantly increased only at 72 hours post CPB (p < 0.05). Serum levels of IL-6 significantly increased at 6 and 72 hours post CPB in all groups (p < 0.01). The Trillium group showed a significant increase of IL-10 compared to the control group at 72 hours post CPB (p < 0.05). Serum levels of NOx in the Phosphorylcholine group significantly decreased at 6 hours post CPB compared to baseline (p < 0.05). Both the Bioline and Phosphorylcholine groups showed statistical decreases in serum NOx levels compared with other groups at 6 hours post CPB (p < 0.05). A significant difference in NOx levels between the Bioline and the control group was also observed at 72 hours post CPB. Myeloperoxidase levels were significantly elevated at 6 and 72 hours post CPB in all groups (p < 0.05). Inflammatory response and oxidative stress are elevated during CABG with CPB. Heparin-coated and the Phosphorylcholine-coated circuits induce less inflammatory responses and oxidative stress compared to other circuits.

The aim of this study was to examine the influence of preoperative atorvastatin therapy on oxidative stress in coronary artery bypass grafting (CABG) patients. Forty patients who underwent elective CABG were enrolled into the study. Of these patients, 20 received atorvastatin (Group I) for 15 days prior to surgery and 20 patients did not use any antihyperlipidemic agents preoperatively (Group II). Serum paraoxonase 1 (PON1) and arylesterase activities, and total antioxidant status (TAS) and total oxidant status (TOS) were measured before surgery and at 1, 6 and 24 hours after the operation. Paraoxonase 1 and arylesterase activities (p<0.001) and TAS levels (p<0.001 for 1^st hour and p<0.05 for 6^th hour) in Group II were significantly reduced at the 1^st and 6^th hours after the operation, whereas the activities of the enzymes (p<0.01) and TAS levels (p<0.05) were significantly reduced only at the 1^st hour after the operation in Group I. The total oxidant status of both groups was significantly increased at the 1^st hour after operation (p<0.05 for Group I and p<0.01 for Group II). In conclusion, 15 days of preoperative atorvastatin therapy does not significantly change either the serum PON1 activity or the oxidative stress after CABG.

Background: Extracorporeal membrane oxygenation is a cardiopulmonary supportive therapy. In this study, we reviewed our experience with extracorporeal membrane oxygenation support and tried to identify measurable values which might predict in-hospital mortality. Methods: From January 2004 through December 2008, 50 of 21,298 adult patients received venoarterial extracorporeal membrane oxygenation. We retrospectively analyzed clinical records of these 50 consecutive patients. Details of demographics, preoperative measurements, clinical characteristics at the time of extracorporeal membrane oxygenation implantation, extracorporeal membrane oxygenation-related complications and in-hospital mortality were collected. Logistic regression analyses were performed to investigate predictors of mortality. A p-value ≤ 0.05 was accepted as significant. Results: Thirty-eight patients were weaned from extracorporeal membrane oxygenation and 33 patients survived to discharge. The overall survival rate was 66%. In a multiple logistic regression analysis, blood lactate level before initiation of extracorporeal membrane oxygenation was a risk factor associated with in-hospital mortality (OR 1.27 95% CI 1.042-1.542). To evaluate the utility of the lactate in predicting mortality, a conventional receiver operating characteristic curve was produced. Sensitivity and specificity were optimal at a cut-off point of 12.6mmol/L, with an area under the curve of 0.752. The positive and negative predictive values were 73.3% and 83.9%, respectively. Conclusions: Extracorporeal membrane oxygenation is a justifiable alternative treatment for postoperative refractory cardiac and pulmonary dysfunction which could rescue more than sixty percent of otherwise fatal patients. Patients with pre-extracorporeal membrane oxygenation lactate levels above 12.6mmol/L are at higher risks for in-hospital death. Evidence-based therapy for this group of high risk patients is needed.

In open heart surgery in neonates and small children, the cardiopulmonary bypass circuit surface and the priming volume are relatively large in relation to patient size and blood volume. Therefore, the use of allogeneic blood is inevitable to maintain the optimal hematocrit level during bypass. To avoid the deleterious effects of blood transfusion, as well as to reduce the contact surface of blood with artificial materials, we stepwise reduced the bypass circuit size. Use of the commercially available minimized elements and an adjusted set-up of the system allowed us to reduce usage of allogeneic blood in the prime and during the bypass. However, other supplemental measures are needed to obtain asanguineous cardiopulmonary bypass for neonatal and infant patients.

Background: The most important side effect of epidural anesthesia is hypotension with functional hypovolemia. Aggressive infusion therapy can reduce the hypotension effect. However, in conjunction with cardiopulmonary bypass, it can increase acute lung injury. We hypothesized that epidural anesthesia, by reducing cardiac sympathetic tonus, with subsequent better pulmonary flow, does not increase lung interstitial fluids.

Methods: Sixty patients undergoing coronary artery bypass graft (CABG) surgery with cardiopulmonary bypass (CPB) were randomized to combined general anesthesia with epidural anesthesia / analgesia, (EA) group, and to general anesthesia with i/v opiate analgesia, (GA) group. Patients in the EA group received a high thoracic epidural, preoperatively. Intraoperatively, 0.25% bupivacaine 8 mL/h was infused and general anesthesia with sevoflurane was followed by bupivacaine infusion for 48 hours postoperatively. General anesthesia in the GA group was with sevoflurane and fentanyl 10 - 12 µg/kg and analgesia with pethidinum 0.1 - 0.4 mg/kg i.v. postoperatively. Global end-diastolic volume index (GEDI), intrathoracic blood volume index (ITBI) and extravascular lung water index (ELWI) were measured before anesthesia, before CPB and 15, 60, 180, 600 min. and 24 hr after CPB. Duration of mechanical lung ventilation was registered in both groups.

Results: ITBI and GEDI were significantly higher in the EA group at all time points of measurement (ITBI 945.6±146.4 ml/m² and 870.6±146.5 ml/m² vs. 1118±153.2 ml/m² and 1020±174.9 ml/m²; GEDI 720±96.19 ml/m² and 775.0±159.5 ml/m² vs. 805.4±97.59 ml/m² and 888±117.3 ml/m²). GEDI was significantly lower in the GA group compared with baseline (801.9±132.4 ml/m² vs. 695±169.2 mL/m²). ELWI was significantly higher in the GA group (7.233±1.35 ml/kg and 7.333±1.32 ml/kg vs. 8.533±1.45 ml/kg and 8.633±1.71 ml/kg), but without significant changes in the EA group. Duration of mechanical lung ventilation was shorter in the EA group (663.7±98.39 min. vs. 362.2±33.72 min.).

Conclusions: Epidural anesthesia / analgesia does not increase interstitial lung fluids by increasing intrathoracic blood volume or the amount of infusion fluids in patients undergoing cardiac surgery under cardiopulmonary bypass. There is, also, a decreased duration of mechanical lung ventilation.

Background: The scavenger receptor for complexes hemoglobin-haptoglobin (CD163), which is expressed on monocytes/ macrophages, is shed to the body fluids in a soluble form (sCD163).

Objectives: To evaluate the dynamics of sCD163 in the blood of patients undergoing cardiac surgery.

Patients and Methods: Sixty-one adult patients who underwent coronary artery bypass grafting (CABG) were enrolled in the study. They were assigned to undergo CABG using either cardiopulmonary bypass (CPB), "on-pump", (22 patients), modified CPB, mini "on-pump", (17 patients) or without CPB, "off-pump", (22 patients) surgery. Serum levels of sCD163 in venous blood samples taken before and after surgery, and during an early postoperative period, were evaluated by Macro 163^TM diagnostic kit (IQ Products, Groningen, NL).

Results: Compared to the preoperative levels ("on-pump"; 344 ng/mL, "off-pump"; 314.5 ng/mL, mini-invasive "on-pump"; 336.5 ng/mL) serum levels were elevated at the finish of surgery, reaching maximum at the 1^st postoperative day ("on-pump"; 658 ng/mL; p<0.05, "off-pump"; 810.5 ng/mL; p<0.01; mini-invasive "on-pump"; 663 ng/mL; non-significant). No significant differences regarding the serum levels of sCD163 between different surgical approaches were found.

Conclusion: Serum level of sCD163 scavenger molecule for hemoglobin is elevated at the end of surgery and at the 1^st postoperative day, being little influenced by cardiopulmonary bypass.

Background: Carotid artery stenosis (CAS) is a well-known risk factor for perioperative stroke in cardiac surgery. It is unclear whether preoperative carotid screening should be applied to all patients. Carotid intervention concomitantly with cardiac operations is also controversial. Our objective was to identify the prevalence of significant CAS and its related risk factors by applying a protocol of preoperative carotid screening to all patients undergoing cardiac surgery.

Methods: We studied 307 patients who were primarily screened preoperatively by duplex Doppler ultrasonography. Catheter carotid angiography or transcranial Doppler was performed on equivocal cases. Univariate and multivariate analyses were applied across selected parameters to identify risk factors for significant CAS (> 70%). The prevalence of CAS and perioperative stroke rates were determined.

Results: Twenty-two patients with severe and 18 with moderate carotid stenosis were identified. Further radiological evaluation with catheter carotid angiography and transcranial Doppler confirmed the presence of significant CAS in 20 patients who underwent carotid stenting or endarterectomy before the open heart surgery. The cardiac surgeon was free to modify the surgical technique according to the preoperative assessment. No patient had major stroke perioperatively, while two minor strokes with complete neurologic recovery have been documented. The history of stroke and the presence of bruit on clinical examination were the only significant predictors of severe carotid disease.

Conclusion: Careful clinical examination together with detailed previous history taking can identify the majority of patients with CAS. Further data are required for the construction of a scientifically valid policy as a guideline.