Objective: Closed circuit extracorporeal circulation (CCECC) has been developed to reduce deleterious effects of standard cardiopulmonary bypass (CPB). This study compares the effects of CCECC (CORx system), CPB, and off-pump coronary artery bypass grafting (OPCAB) on red blood cell damage, coagulation activation, fibrinolysis and cytokine expression. Methods: Thirty patients underwent coronary artery bypass grafting (CABG). Twenty of them were randomized into two groups: CCECC (n=10), CPB (n=10). While not randomized, OPCAB (n=10) served as a separate reference group. CCECC and CPB patients received cardioplegic arrest. Interleukin 6 (IL-6), free hemoglobin (fHb), von Willebrand factor activity (vWf), thrombin–antithrombin-III-complex (TATc), prothrombin fragment 1.2 (F 1+2) and plasmin–antiplasmin complex (PAPc) were assessed preoperatively, perioperatively and 24h postoperatively. Results: CCECC showed significantly lower red blood cell damage than CPB (fHb: CCECC, 7.1± 5.7μmol/l; CPB, 16.8±11.4μmol/l; P=0.025; OPCAB, 3.4±1.1μmol/l). Perioperatively, CCECC exhibited significantly lower activation of coagulation and fibrinolysis than CPB, but did not differ from OPCAB (vWf: CCECC, 133±52%; CPB, 241±128%; P=0.052; OPCAB, 153±58%; TATc: CCECC, 4.7±0.9ng/ml; CPB, 31.1±15.8ng/ml; P≪0.001; OPCAB, 2.4±0.6ng/ml; PAPc: CCECC, 214±30ng/ml; CPB, 897±367ng/ml; P≪0.001; OPCAB, 253±98ng/ml). In contrast, fibrinolysis markers and IL-6 were markedly increased in CCECC postoperatively (PAPc: CCECC, 458±98ng/ml; CPB, 159±128ng/ml; P≪0.001; OPCAB, 262±174ng/ml; IL-6: CCECC, 123.4±49.8pg/dl; CPB, 18.8±13.1pg/dl; P≪0.001; OPCAB, 31.6±26.2pg/dl). Conclusions: CCECC for CABG is associated with a significant reduction of red blood cell damage and activation of coagulation cascades similar to OPCAB when compared with conventional CPB while a delayed fibrinolytic and inflammatory activity was observed. These findings require further investigation to verify the promising concept of CCECC.
Extracorporeal circulation (ECC) is an integral part of cardiac surgery. Yet, the contact with artificial surfaces, mechanical stress, shear, and suction forces within the ECC pose a pronounced risk for damaging the corpuscular components of the blood. These suction forces may be reduced by a repositioning of the roller pumps employed below the reservoir. Furthermore, the repeated compression of the involved silicone tubing is likely to cause degradation. We present our observations regarding changes in the ECC performance following this degradation process. In vitro experiments were performed in a standard as well as a simplified ECC setup and included measurements of pressure, effective flow, and tubing restoring force over a time frame of 12 hours with two different pump positions utilizing transit time flow measurement. Suction forces within the tubing could be significantly reduced by shifting the pump position below the reservoir. Regardless of the setup, the tubing showed significant loss of restoring force as well as effective flow over time. A shift of the pump position within the ECC setup can be recommended to prevent blood damaging negative pressures. Further research is necessary to evaluate the exact cause of the reduction of restoring force overtime as well as its risks for the patients. Finally, our results underline the importance of transit time flow measurements to collect reliable flow data.
Objectives: Negative pressure therapy is routinely used in deep sternal wound complications because of good overall results. Although efficacy has repeatedly been proven, the safety of these systems, however, is controversial discussed, especially in cases of direct contact with vascular structures.
Background: Polymeric heart valves aim to unify the advantageous hemodynamic of biological with the longevity of mechanical prostheses by using flexible synthetic materials. Besides mimicking the natural form of the heart valve, the new shapes and functioning principles can be explored to better address the physical properties of these polymers. The rapid development of 3D printing, including options to print in silicone has given us the tools to create, test and improve these new types in yet unknown speed. We created several improved prototypes of the TIPI valve based on the PIZZA valve (patent number DE 10 2008 012 438 B4) as well as of the TRISKELION another construction principle developed in our institution. These were then tested, compared and further developed.
Objectives: Negative pressure therapy is routinely used in deep sternal wound complications. In recent years the combination of vacuum assist closure and instillation with antiseptic solution has become an additional option for these patients. However, this therapy is controversially discussed, especially is cases of direct contact with mediastinal and heart structures. In this retrospectively study, we looked at safety and efficacy of negative pressure therapy combined with DAB 7/0.02% polyhexanid (Lavanid 1% solution) instillation in such patients.
Mitral valve reconstruction (MVR) is one of the cardiosurgical procedures which cannot be substituted by any intervention owing to the quality of the quasi-anatomical, physiological repair. However, technique and strategies have changed over the years. We looked at procedural characteristics and outcome in an all-comer, non-selected cohort of patients.738 out of 1.977 patients were retrospectively analyzed receiving MVR with and without concomitant procedures. The cohort was divided into three periods. P1: 2004-2009 (134 pts.); P2: 2010-2014 (294 pts.), and P3: 2015-2019 (310 pts.).Early mortality increased from P1 to P2 and decreased from P2 to P3 (9% P1, 13% P2, 10% P3). All patients received an annuloplasty-ring. In P1 resection measures dominated. In P3 artificial chordae were dominant. Age, BMI, and risk scores correlated with early mortality. Survival rates were 66% (5-years), 55% (10-years), 44% (15-years) in P1, 63% (5-years), 50% (10-years) in P2, and 80% (5-years) in P3. Odds ratio for reduced long-term survival were concomitant venous only bypass surgery (10-years 2,701, p = 0.026). 10-year survival was positively influenced by isolated MVR (0.246, p = 0.001), concomitant isolated arterial bypass (IMA) (0.153, p = 0.051), posterior leaflet measure (0.178, p<0.001), and use of artificial chordae (5-years 0.235, p<0.001).Indication for ring implantation remained mandatory while preference changed alongside improved designs. Procedural characteristics changed from mainly resection maneuvers to predominant use of artificial chordae. Long-term results were negatively influenced by co-morbidities and positively influenced by posterior leaflet repair and artificial chordae. MVR underwent a qualitative evolution and remains a valuable cardiosurgical procedure.
Background: Demographic changes have led to an increase in the proportion of older patients undergoing heart surgery. The number of endocarditis cases is also steadily increasing. Given the sharp increase in patients who have received valve prostheses or electrophysiological implants, who are on chronic dialysis or taking immunosuppressants, the interdependence of these two developments is quite obvious. We have studied the situation of older patients suffering from endocarditis compared to younger ones. Are they more susceptible, and are there differences in outcomes? Patients and Methods: A total of 162 patients was studied from our database, enrolled from 2020 to 2022. Fifty-four of them were older than 75 years of age (mean age 79.9 ± 3.8 years). The remaining 108 patients had a mean age of 61.6 ± 10.1 years. EuroSCORE II (ES II) was higher in the older patients (19.3 ± 19.7) than in the younger ones (13.2 ± 16.84). The BMI was almost identical. The preoperative NYHA proportions did not differ. A statistical analysis was performed using R. Results: Older patients had a lower left ventricular ejection fraction (LVEF), a higher proportion of coronary heart disease (CHD), a higher amount of N-terminal probrain natriuretic peptides (NT-proBNPs), worse coagulation function, worse renal function than younger patients, and were more often valve prosthesis carriers compared to the younger patients. The diagnostic interval was 66.85 ± 49.53 days in the younger cohort, whereas it was only 50.98 ± 30.55 in the elderly (p = 0.081). Significantly fewer septic emboli were observed in the older patients than in the younger patients, but postoperative delirium and critical illness polyneuropathy and critical illness myopathy (CIP/CIM) were observed significantly more frequently compared to younger patients. In-hospital mortality was higher in older patients than in younger patients, but did not reach statistical significance (29.91% vs. 40.38%; p = 0.256). The postoperative clinical status was worse in older patients than in the younger ones (NYHA-stage, p = 0.022). Conclusions: Age did have an impact on the outcome, probably due to causing a higher number of cumulative preoperative risk factors. However, an interesting phenomenon was that older patients had fewer septic emboli than younger patients. It can only be speculated whether this was due to a shorter diagnostic interval or lower mobility, i.e., physical exertion. Older patients suffered more frequently than younger ones from typical age-related postoperative complications, such as delirium and CIP/CIM. In-hospital mortality was high, but not significantly higher compared to the younger patients. Considering the acceptable mortality risks, and in light of the lack of alternatives, older patients should not be denied surgery. However, individual consideration is necessary.
Demographic changes and aggressive platelet inhibition have resulted in a marked increase in blood- and coagulation product expenditure and costs in cardiac surgery. We analyzed "bedside" coagulation test (ROTEM) in order to verify clot forming quality for the purpose of finding a cost-effective treatment path.Annual treatment costs of all cardiosurgical patients were analyzed before (729 patients) and after (693 patients) implementation of "bedside" ROTEM. Cumulative numbers and costs of platelet concentrates (PltC), fresh frozen plasma (FFP), red blood cell units (RBC), and coagulation factors: pooled coagulation concentrates (PCC), recombinant factor VIIa (rFVIIa), factor XIII (FXIII), and fibrinogen were assessed. Average monthly numbers and costs were compared. Number of resternotomies and early mortality was assessed and compared in both periods.After ROTEM implementation cumulative RBC expenditure showed 25% decrease while PltC exhibited 50% decrease. FFP expenditure remained unchanged. PCC, FXIII were markedly reduced (-80%) while rFVIIa were entirely omitted. Fibrinogen, however, increased two-fold. Cumulative average monthly costs of all blood products decreased from 66,000 euro to 45,000 euro (-32%). Coagulation factor average monthly costs decreased from 60,000 euro to 30,000 euro (-50%) yielding combined savings of 44%. In contrast, average monthly costs for ROTEM were 1.580 euro. Total number of resternotomies decreased from 6.6% to 5.5% while early mortality (5.9%; 6.0%) remained stable.Cumulative costs for treatment of perioperative coagulation disorders can be reduced by "bedside" ROTEM analysis to achieve a selective substitution management. Saved costs for blood- and coagulation products clearly outweighed the expenses of ROTEM. Adequate differential coagulation management can therefore be cost-effective.
Background: In an increasingly senescent population stented biological valves have regained renewed popularity because of the absence of anticoagulation, while the stented design allows for safe and easier implantation. Constructed bovine pericardial valves as well as valves with porcine cusps are used, both of which exhibit good clinical results although degeneration still appears. While clinical hemodynamic studies did not show particular differences between both valves types, the opening and closure behavior of native cusps and artificially constructed pericardial leaflets is different. It is unclear whether these phenomena account for differences in load and stress which may influence onset and course of degeneration. Material and Methods: Edwards Perimount (EP) and Medtronic Mosaic (MM) heart valves with diameters of 21 mm, 23 mm, and 25 mm were investigated in a pulse duplicator. Movements of the valves were visualized with a high-speed camera (1000 frames/sec). Mean transvalvular gradient (mm Hg), dissipated power (mW), and power transfer by stretching (mW), mean orifice area (mm²), opening time (ms), and closure time (ms) were analyzed in a range of cardiac outputs from 1.4 l/min to 6.3 l/min and 70 beats per minute. Results: Closure times were generally longer than opening times for both valve types. Opening time of EP valves was longer than opening time of the MM valves of the same size (EP23: 31.2 ± 2.5 ms; MM23: 12.7 ± 0.1 ms). With respect to closure times, however, there were no marked differences between all valves (EP23: 69.3 ± 2.0 ms; MM23: 63.2 ± 6.3 ms). Smaller sized Perimount valves exhibited lower mean transvalvular gradients than Mosaic valves of the same size (EP23: 7.21 ± 0.07 mm Hg; MM23: 10.5 ± 0.15 mm Hg). In larger sizes these differences diminished. Power transfer to the valve's structures was significantly enhanced in EP valves (EP23: 134 ± 1.3 mW; MM23: 64 ± 0.9 mW). Conclusions: While valves with constructed pericardium showed lower mean transvalvular gradients, particularly in the smaller sizes, this valve type exhibited alterations of movement performance in contrast to porcine valves. It can be speculated that constant power transfer to the valve's structures may result in an earlier degeneration because of the impact of the increased load and stress on the suspension apparatus of the constructed pericardial leaflets.
