[The "sacrificial electrode" : A safe option for the management of pacemaker infections in pacemaker-dependent patients]. / Die "Opferelektrode" : Eine sichere Option zum Management von Schrittmacherinfektionen bei schrittmacherpflichtigen Patienten.

As the number of cardiac implantable electronic devices (CIEDs) increases, so does the need to revise such systems. Pacemaker-dependent patients with a CIED infection are particulary challenging for the attending physician. Here, the CIED cannot simply be removed without replacement. Gold standard therapy is a sufficient, prolonged antibiosis, the complete removal of the CIED, and the installation of a temporary pacemaker system - usually by means of a transvenous probe or epimyocardial probe via thoracotomy. The disadvantages of these therapies are the insecure positioning of the unfixed transvenous or the invasiveness of the epimyocardial probes. Alternatively, we have since 2015 established a concept with the so-called "sacrificial" electrode. For this purpose - during the explantation of the infected CIED - a conventional, transvenous screw electrode is anchored via the subclavian vein in the right ventricle and is then connected cutaneously to an aggregate. If the anti-infective therapy is successful, a new CIED is implanted whenever possible over the contralateral side in the usual way. Stimulation via the sacrificial electrode can be stopped and the probe removed. This method is technically easy to perform and offers great advantages: no dislocation of the probe and maintained patient mobility.

Regulation of endothelial nitric oxide synthase (eNOS) in myocardium subjected to cardioplegic arrest.

BACKGROUND: Nitric oxide (NO) production by both coronary endothelial cells and cardiomyocytes is thought to play a significant role in myocardial pathophysiology following ischemia/reperfusion (I/R). METHODS: In thirteen pigs subjected to 1 hour cardioplegic arrest (CA) on CPB, left ventricular (LV) biopsies were collected prior to CPB (baseline), at 60 min CPA, at 15 and 30 min reperfusion on CPB, and at 120 min post CPB. LV specimens were immunocytochemically stained against phospho-eNOS (Ser1177), phospho-eNOS (Thr495), phosphorylated ERK1/2, and AKT/PKB. Four additional pigs without CA served as controls. Cardiomyocytes were quantitatively investigated using TV densitometry (gray units: U). RESULTS: After 60 min CA phosphorylation of eNOS (Ser1177) increased significantly and remained elevated until 30 min of reperfusion. In contrast, eNOS (Thr495) phosphorylation remained unchanged during CA and throughout reperfusion. In control animals, eNOS phosphorylation remained unchanged. Akt/PKB activity significantly increased after 60 min CA and decreased thereafter. ERK1/2 activity remained unchanged during ischemia but increased during reperfusion. CONCLUSIONS: ENOS activation during ischemia occurs through phosphorylation at Ser1177 mediated by Akt/PKB. ERK1/2 does not seem to be involved in myocardial eNOS regulation especially not via phosphorylation at eNOS (Thr495).

Chronic treatment with carvedilol improves Ca(2+)-dependent ATP consumption in triton X-skinned fiber preparations of human myocardium.

Evidence is given that beta-blocker treatment differentially influences gene expression and up-regulation of beta(1)-adrenoceptors in human myocardium. Here, we investigate whether long-term treatment with carvedilol or metoprolol may functionally alter myofibrillar function in end-stage human heart failure. Investigations were performed in Triton X (1%, 4 degrees C, 20 h)-skinned fiber preparations of explanted hearts from patients undergoing heart transplantation due to idiopathic dilative cardiomyopathy. Five patients were not on beta-adrenoceptor blocker treatment (DCM_NBB), and 5 patients received either carvedilol (DCM_CAR) or metoprolol (DCM_MET). Nonfailing (NF) donor hearts (n = 5), which could not be transplanted due to technical reasons, were investigated for comparison. Ca(2+)-dependent tension (DT) development and actomyosin-ATPase activity (MYO) were measured and tension-dependent ATP consumption was calculated by the ratio of DT and MYO ("tension cost"). In addition, we measured the phosphorylation of troponin I (TNI) by back phosphorylation. Maximal DT and TNI phosphorylation were reduced, with myofibrillar Ca(2+) sensitivity of DT and MYO as well as tension cost being increased in DCM_NBB compared with NF. Metoprolol treatment restored TNI phosphorylation, decreased Ca(2+) sensitivity of tension development and of myosin-ATPase activity, but did not alter the tension-dependent ATP consumption. Carvedilol treatment improved maximal DT and significantly decreased tension-dependent ATP consumption without altering myofibrillar Ca(2+) sensitivity. TNI dephosphorylation was increased in patients treated with carvedilol. In conclusion, chronic beta-adrenoceptor blockade functionally alters myofibrillar function. The more economic cross-bridge cycling in patients under carvedilol treatment may provide an explanation for the efficacy of carvedilol in the treatment of chronic heart failure patients.

Risk stratification models fail to predict hospital costs of cardiac surgery patients.

BACKGROUND: The aim of this prospective study was to determine if commonly used risk stratification models can predict total hospital costs in cardiac surgical patients. METHODS: Between October 1st and December 31st 2003, all consecutive adult patients undergoing cardiac surgery on CPB at our institution were classified using seven risk stratification scoring systems: EuroSCORE, Cleveland, Parsonnet, Ontario, French, Pons, and CABDEAL. Total hospital costs for each patient were calculated on a daily basis including preoperative diagnostic tests, operating room costs, disposable materials, drugs, blood components, costs for personnel, and hospital fixed-costs. Linear regression analysis was used to determine the correlation between costs and the seven risk stratifications models as well as length of stay (LOS) on ICU. The Spearman correlation coefficient was calculated from the regression line, and an analysis of residuals was performed to determine the quality of the regression. RESULTS: A total of 252 patients were operated for CABG (n=175), valve (n=39), CABG plus valve (n=21), thoracic aorta (n=13) and miscellaneous (2 myxoma, 1 ASD, 1 pulmonary embolism). Mean age of the patients was 66.0+/-11.4 years, 29.4% were female. LOS on ICU was 3.3+/-6.3 days and the 30-day mortality rate was 6.7%. Spearman correlation between the seven risk stratification models and hospital costs was below r=0.32 (p=0.0001), but was r=0.94 (p=0.0001) between ICU LOS and costs. CONCLUSIONS: Total hospital costs can be identified by length of ICU stay. None of the common risk stratification models accurately predicted total hospital costs in cardiac surgical patients.

VDD-pacemaker in children--a long-term therapy?

AIMS: Transvenous AV-synchronous pacing in children started with the invention of smaller sized VDD leads and miniaturization of pacemakers. Whether or not this is a favourable long-term therapy was retrospectively investigated by us based on data from our records. METHODS: From May 1977 to July 2001 we implanted pacemakers in 104 children younger than 15 years of age. In 55 patients transvenous leads were implanted. Twelve of these (21.8 %) received a VDD pacemaker for hemodynamic reasons. RESULTS: Ages ranged from 11 months to 14.5 years (mean 7.7 +/- 4.3 y). Sizes of the children ranged from 67 to 141 cm (mean 105.9 +/- 15.5 cm) and body weight ranged from 5.3 to 62.0 kg (mean 22.5 +/- 9.8 kg). The mean follow-up period was 47.5 +/- 15.1 months. In 86.3 % of the time during follow-up pacemakers of which we obtained data were working in the VDD mode. Five of the twelve VDD patients (41.7 %) had to be reoperated because of severe traction on the leads. In all five patients the VDD systems were explanted and the patients changed to dual chamber pacemakers. The period of time between implantation and VDD lead explantation ranged from 24 to 74 months (48.6 +/- 18.5). CONCLUSIONS: VDD pacemakers can be implanted safely even in children with a low complication rate perioperatively. 41.7 % of our VDD patients had to be reoperated within the surveillance time because of severe lead tension due to thoracic growth. In our experience VDD pacemakers in smaller children seem to be a temporary solution to bridge AV-synchrony from a young age to DDD pacing in young adulthood.

[Is measuring by portable heart rate monitors (sport watches) dependable in patients with an implanted pacemaker?]. / Messen tragbare Herzfrequenz-Messgeräte (Sportuhren) bei Schrittmacherpatienten zuverlässig?

BACKGROUND AND OBJECTIVE: Regular physical exercise is advantageous for physical fitness and endurance. The intensity of exercising can be controlled by portable heart rate monitors. The aim of the study was to investigate if wearable monitors work properly in pacemaker patients. PATIENTS AND METHODS: In 30 patients with an implanted single or dual chamber pacemaker made by five different manufacturers their heart rate was determined simultaneously by surface ECG and Holter ECG, and was compared with the heart rates derived from portable heart rate monitors (Polar A1) at rest, during 6 minutes in-house walk, and while exercising at 25, 50, and 75 watts in a bicycle exercise test. The tests were done with pacing set at uni- as well as bipolar stimulation mode. RESULTS: At rest in two of 30 patients (6,6 %) paced in unipolar mode the portable heart rate monitors counted double. Under exercise conditions the portable monitors counted double in six of 26 patients (23 %) while being stimulated in unipolar mode. In bipolar stimulation mode, the portable heart rate monitors were working properly in all patients under all conditions. CONCLUSIONS: Patients with an implanted bipolar pacing system can control their physical exercising safely and accurately by means of portable heart rate monitors. Pacemaker patients who are planning regular physical exercising should be provided with an implanted bipolar pacemaker system.

The effect of preoperative antiplatelet therapy in coronary artery surgery: blood transfusion requirements for patients on cardiopulmonary bypass.

INTRODUCTION: Bleeding after heart operations remains a common complication and contributes to morbidity and death. Recent studies have suggested that antiplatelet therapy (APT) may not increase homologous blood requirements in coronary bypass surgery. The purpose of this study was to examine the influence of APT therapy on haemorrhage and transfusion requirements in patients undergoing coronary artery bypass (CABG) on cardiopulmonary bypass (CPB). MATERIALS AND METHODS: Records from 290 consecutive patients who underwent CABG with CPB were retrospectively reviewed, including 145 patients who received APT within 5 days prior to surgery and 145 control patients (CON). Blood loss was measured up to 24 h. Demographic and clinical patient data were collected until hospital discharge. RESULTS: Both groups were well matched with respect to demographic and intra-operative data. There was significantly (p < 0.0005) more mediastinal tube drainage at 24 h in the APT group (1123 mL +/- 537 mL) compared to CON patients (874 mL +/- 351 mL). In addition, the APT group received significantly more units of blood (APT: 2.6 +/- 2.5 vs CON: 1.6 +/- 1.8; p < 0.0005), platelet units (APT: 1.2 +/- 1.8 vs CON: 0.2 +/- 0.8; p < 0.0005), and fresh frozen plasma units (APT: 2.0 +/- 2.2 vs CON: 1.3 +/- 2.0; p = 0.01). CONCLUSION: This study suggests consideration should be given to delaying elective CABG for patients who have received APT treatment until APT is discontinued for at least 5 days.

Interference by cellular phones with permanent implanted pacemakers: an update.

AIMS: The aim of this study was to test pacemakers with feedthru filters for interference with a digital cellular telephone. METHODS: The study comprised 100 patients having their first pacemaker implantation between January 2001 and May 2003. A GSM-standard cellular phone was tested in the standby, dialing and operating mode against 23 single-chamber and 77 dual-chamber pacemakers. Continuous surface electrocardiograms, intracardiac electrograms, and marker channels were recorded when calls were made by a land phone to the cellular phone. RESULTS: In 2 patients we observed pacing inhibition with the cellular phone positioned directly above the pacemaker pocket. The unipolar and bipolar ventricular sensitivity setting was 0.25 mV in one dual-chamber pacemaker, and when we changed the sensitivity to 0.50 mV and higher no interference could be detected. The second inhibition occurred in a single-chamber pacemaker with unipolar and bipolar ventricular sensitivity setting of 0.5 mV, where a sensitivity change to 1.0 mV eliminated the interference. CONCLUSION: Anticipating a correct setting of ventricular sensitivity, currently available pacemakers equipped with feedthru filters do not show any interference with cellular phones. Since interference was only observed with sensitivity settings below 0.50 mV, we recommend that permanent programming of ventricular sensitivity should be set at 2.0 mV and higher.

Impact of tranexamic acid vs. aprotinin on blood loss and transfusion requirements after cardiopulmonary bypass: a prospective, randomised, double-blind trial.

INTRODUCTION: Aprotinin (AP) reduces blood loss and transfusions after cardiopulmonary bypass (CPB), but may sensitise patients and is expensive. Tranexamic acid (TA) has less side-effects, but data regarding its efficacy are controversial. The aim of our prospective, randomised, double-blind study was to compare the impact of AP vs. TA on drainage blood loss and transfusion requirements in patients undergoing first time CABG on CPB. MATERIALS AND METHODS: One hundred and twenty adult patients were randomised to receive either high-dose AP according to Hammersmith or a total of 2 g TA. Perioperative blood products were transfused in a standardised fashion. Blood loss was measured up to 24 h. Demographic and clinical patient data were collected until hospital discharge. RESULTS: The data from 118 patients (TA: n = 58, AP: n = 60) who completed the study according to protocol were analysed. Blood loss at 24 h postoperation in TA patients was significantly higher (896 +/- 354 ml) as compared to AP patients (756 +/- 347 ml; p = 0.03). TA patients received 1.5 +/- 1.5 units of red blood cells (AP: 1.5 +/- 1.7, p = 1.0), 1.3 +/- 2.0 units of fresh frozen plasma (AP: 1.0 +/- 2.0, p = 0.38) and 0.5 +/- 1.4 units of platelets (AP: 0.2 +/- 0.7, p = 0.15). Clinical data, including perioperative myocardial infarction rate, acute renal failure, mechanical ventilation, hospital stay and mortality, were not significantly different between either group. CONCLUSION: Our data show a difference in blood loss between TA and high-dose AP. Although statistically significant, it has little clinical relevance, because perioperative transfusion requirements were similar for both groups. Thus, TA appears to be a cost-effective alternative to AP in primary CABG patients.

[S2 guideline for infectious endocarditis]. / S2 Leitlinie zur Diagnostik und Therapie der infektiösen Endokarditis. Finale Version 5.0 08/2004.

Microbe-induced (infectious) endocarditis is an endovascular infection, caused mainly by bacteria, of cardiovascular structures. The major predilection site are the native heart valves, but involvement of implanted intracardiac foreign material is increasingly being seen. The mortality rate of infectious endocarditis depends on clinical factors and the causal agent, but also on the time of the establishment of the diagnosis and the initiation of appropriate treatment. In Germany, the current mortality rate ranges up to 18%. Between January 2003 and July 2004, with the aim of improving patient care and thus the outcome of this condition, a guideline commission worked out recommendations for the diagnosis, treatment and management of the disease for the use of general practitioners and hospital physicians, in particular microbiologists, infectiologists, cardiologists and cardiac surgeons. The basis for this guideline was the systematic search through the literature of the European guideline. On the 16th and 28th of June 2004, the entire guideline was formerly approved in a nominal group process.

Morphology and density of initial lymphatics in human myocardium determined by immunohistochemistry.

BACKGROUND: Myocardial edema is a common finding in congestive heart failure, transplant rejection, and cardiomyopathy. Although pathological alterations in the lymphatic morphology are part of the underlying disease, knowledge on these changes is limited. However, lymphatic morphology may be investigated by immunohistochemical staining for fms-like tyrosine 4 kinase (flt-4), which is specific for lymphatic endothelium in adult tissue. METHODS: We used myocardial tissue of ventricular out flow tract taken from five human semilunar valves harvested as allografts but unsuitable for implantation for analysis, performing immunohistochemical staining for flt-4 with a commercially available antibody. Lymphatic morphometry was completed according Gundersen method. RESULTS: Immunohistochemical staining for flt-4 resulted in successful labeling of lymph capillaries in adult human myocardium. Lymph capillary density was calculated as 50.7 +/- 12.5 per mm2 and average diameter was 3.7 +/- 0.7 microm. Conclusions. Lymph capillary morphology in human myocardium may be successfully determined by immunohistochemical staining for flt-4. Tissue samples as small as myocardial biopsies may be used for analysis. Using this method, morphological changes in myocardial lymphatics may be investigated in various cardiovascular diseases.

Transvalvular in vivo gradients of the new generation bileaflet heart valve prosthesis St. Jude Medical Regent in aortic position.

BACKGROUND: By changing the design of the St. Jude Medical Regent prosthesis in shifting both sewing cuff and retaining ring into a completely supra-annular position, the Regent valve has a greater geometric orifice for a given outer diameter. Accordingly, in vitro studies have shown increased effective orifice areas (EOAs) and lower transvalvular gradients. The aim of our study was to determine in vivo transvalvular gradients and EOAs in patients after aortic valve replacement (AVR). METHODS: We investigated 75 patients at 12 to 21 months follow-up after AVR using transthoracic echocardiography. We determined left ventricular systolic and diastolic function, EOA, and transvalvular peak gradient parameters at rest. Outcomes were assessed using the NYHA classification and functional status. RESULTS: No patient experienced cardiac failure. The majority reported good functional status and good quality of life. Five (6.7 %) late deaths were observed within the surveillance period. At follow-up, 92 % of the patients had improved by at least one NYHA class. Transvalvular peak gradients at rest for patients with Regent valves were 25.4 +/- 7.7 mmHg, 19.2 +/- 4.6 mmHg, 15.6 +/- 5.8 mmHg, 14.6 +/- 5.5 mmHg, and 8.5 +/- 2.5 mmHg; EOAs were 1.38 +/- 0.32 cm2, 1.62 +/- 0.49 cm2, 2.24 +/- 0.83 cm2, 2.63 +/- 0.70 cm2, and 3.28 +/- 0.34 cm2 for valve sizes 19 mm, 21 mm, 23 mm, 25 mm, and 27 mm, respectively. CONCLUSIONS: The SJM Regent valve shows excellent in vivo hemodynamics as confirmed by echocardiography. Clinically, 92 % of the patients improved by at least one NYHA class.

The preferential beta3-adrenoceptor agonist BRL 37344 increases force via beta1-/beta2-adrenoceptors and induces endothelial nitric oxide synthase via beta3-adrenoceptors in human atrial myocardium.

1 The present study investigated the effects of the preferential beta(3)-AR agonist BRL 37344 (BRL) on force of contraction (FOC), Ca(2+)-transient and eNOS-activity in human right atrial myocardium. 2 BRL concentration-dependently caused an increase in FOC that was paralleled by an increase in Ca(2+)-transient and a shortening of time to half peak relaxation (T0.5T). These effects were abolished in the presence of propranolol (0.3 micro M). 3 BRL acted as a competitive antagonist towards isoprenaline and in binding experiments it was shown to have a distinct affinity towards beta(1/2)-AR. 4 In immunohistochemical experiments BRL (10 micro M) increased detection of activated eNOS. This effect remained constant in the presence of propranolol (0.3 micro M). 5 BRL increased directly detected NO in DAF-staining experiments. This increase was significantly smaller in the presence of the NO-inhibitor L-NAME. 6 The inotropic effects of BRL were not changed in the presence of L-NMA. 7 These results suggest that the inotropic effects of BRL in human atrium are mediated via beta(1/2)-AR, whereas the increase of atrial eNOS-activity is due to beta(3)- adrenergic stimulation. This increase in eNOS-activity did not influence atrial myocardial contractility. In conclusion, this study shows that beta(3)-adrenergic stimulation is present in human atrium, but may not be functionally as significant as in the left ventricle.

Impact of hematocrit value after coronary artery surgery on perioperative myocardial infarction rate.

BACKGROUND: The optimal hematocrit (HCT) value after coronary artery bypass grafting on cardiopulmonary bypass (CPB) has not yet been established. The purpose of our retrospective study was to investigate the association between HCr at the time of entry into the ICU and perioperative Ml rate. METHODS: We reviewed the charts of 500 consecutive coronary artery surgery patients with respect to biometric data, operative procedure, aprotinin or tranexamic acid use, perioperative drainage blood loss and transfusion requirements, perioperative Ml, ICU stay and hospital mortality. Perioperative Ml was defined as new Q-wave on ECG and CK-MB 250U/I. Patients were categorized into three groups depending on their HCr value at the time of entry into the ICU: low (HCTcu 27%): medium (HCr,cu 28% to 32%); high(HCTrcu > or =33%). RESULTS: Age, gender distribution, preoperative LV function, and previous Ml rate were similar between the three groups. Low HCT patients (n -133) received 3.1 +/- 1.0 (Mean + SD) grafts during 55 +/- 19 minutes aortic cross clamp time, 98 +/- 31 minutes on CPB (medium HCT: n = 257; 3.2 +/- 1.0 grafts, 51 +/- 20 min cross clamp time, 93 +/- 30 min CPB; p - 0.45 vs. low HCT; high HCT: n = 110: 3.3 +/- 1:0 grafts; 53 +/- 20 min cross clamp time; 104 +/- 38 min CPB; p = 0.02 vs. medium HCT). The perioperative Ml rate was 3.8% in the low, 4.3% in the medium, and 6.4% in the high-HCr group (p =0.59 ). Intraoperative red blood cell and fresh frozen plasma transfusions were similar between the groups. In the low-HCa group, 53.4% of the patients received aprotinin during the procedure (medium HCa: 65.4%; high HCT: 77.3%; p<0.001). Drainage blood loss during the first 24 hours on ICU was 834 +/- 453 ml in the low, 757 +/- 485 ml in the medium (p -0.44 vs. low), and 640 +/- 353 ml in the high-HCr group (p = 0.003 vs. low). Postoperative red blood cell and fresh frozen plasma transfusions were highest in the low-HCa group(p<0.001). ICU stay was similar between the groups. Hospital mortality was 0.75% in the low, 1.9% in the medium, and 4.5%in the high-HCa group (p = 0.12). CONCLUSIONS: In this retrospective analysis of 500 consecutive coronary artery surgery patients, we did not find any association between perioperative Ml rate and HCr value on entry into the ICU. These results do not support the recent suggestion that low HCT at the time of entry into the ICU protects against perioperative Ml.

Beta-blockade in 200 coronary bypass grafting procedures.

BACKGROUND: Continuous perfusion of the coronary arteries with high-dose beta-blocker (esmolol)-enriched blood has been shown to represent an alternative for myocardial protection during coronary bypass grafting (CABG). Here, we will report on our experience in 200 unselected consecutive cases where this technique was used. METHODS: Eighty percent of the patients (age: 63.3 +/- 0.6 years, ejection fraction: 60 +/- 1.2 %, emergency cases: 11 %) had 3-vessel disease, 34 % had a history of myocardial infarction within less than 90 days preoperatively. The Euro score amounted to 6 +/- 0.3. During 52 +/- 1.2 min of aortic cross-clamp time on normothermic cardiopulmonary bypass, 2.9 +/- 0.1 distal anastomoses were performed on a slow hypocontractile beating heart induced by continuous infusion of 788 +/- 20 mg esmolol per operation. All data: mean +/- SEM. RESULTS: Postoperatively, patients were ventilated for 25 +/- 5.1 hours and stayed on ICU for 2.3 +/- 0.3 days. The postoperative myocardial infarction rate was 4%. Patients left the hospital after 11.2 +/- 0.4 days. Thirty-day mortality was 2.5 %, and 3-month mortality was 3 %. CONCLUSIONS: High-dose beta-blockade is a safe and effective technique in CABG procedures. It may be especially advantageous in high-risk patients.

Cardiopulmonary bypass copolymer surface modification reduces neither blood loss nor transfusions in coronary artery surgery.

OBJECTIVE: Surface-modifying additives (SMA) have been suggested for improving cardiopulmonary bypass (CPB) circuit biocompatibility, potentially minimizing inflammatory complications and bleeding associated with CPB. The purpose of this prospective, randomized clinical study was to compare a novel copolymer surface-modified CPB circuit (SMARXT; COBE Cardiovascular) against the unmodified circuit. METHODS: We randomized 122 patients with isolated coronary artery disease subjected to first-time surgery on CPB into either the SMA (n = 62) or the control group (n = 60). Exclusion criteria included renal insufficiency, liver disease, coagulopathy, anticoagulation therapy < 6 days preop, carotid artery stenosis > 70 %, and a history of stroke. We collected perioperative clinical data including drainage blood loss, transfusion requirements, duration of mechanical ventilation, and ICU stay. Platelet function was determined pre- and post-CPB. RESULTS: SMA patients received 3.2 +/- 0.9 (SD) grafts during 48 +/- 16 min of aortic cross clamp and 91 +/- 30 min CPB (Control: 3.0 +/- 0.9 grafts; p = 0.33, 46 +/- 14 min AXC; p = 0.36, and 84 +/- 23 min CPB; p = 0.14). In the SMA group, 23 patients (37 %) received red blood-cell transfusions, 9 patients (15 %) fresh frozen plasma, and 3 patients (5 %) received platelets (control: n = 27 [46 %], p = 0.44; n = 10 [17 %], p = 0.91; and n=4 [7 %], p = 0.71, respectively). Platelet count on CPB fell to the same level in both groups. In SMA patients, platelet function decreased from 94.2 +/- 24.9 % pre-CPB to 79.5 +/- 32.8 % post-CPB (p = 0.043) (control: from 87.7 +/- 25.6 % to 69.4 +/- 34.7 %; p = 0.001). Postoperative drainage blood loss, mechanical ventilation duration, and ICU stay were similar in both groups (p > 0.3). One patient of the control group was excluded due to surgical bleeding, and one SMA patient died. CONCLUSIONS: Our results show that the surface-modified CPB circuit decreased neither blood loss nor transfusions despite slightly better platelet function preservation compared to the unmodified circuit. This type of CPB circuit surface modification does not appear to improve clinical outcome in low-risk coronary artery surgery patients.

Myocardial fluid balance.

Fluid accumulation in the cardiac interstitium or myocardial edema is a common manifestation of many clinical states. Specifically, cardiac surgery includes various interventions and pathophysiological conditions that cause or worsen myocardial edema including cardiopulmonary bypass and cardioplegic arrest. Myocardial edema should be a concern for clinicians as it has been demonstrated to produce cardiac dysfunction. This article will briefly discuss the factors governing myocardial fluid balance and review the evidence of myocardial edema in various pathological conditions. In particular, myocardial microvascular, interstitial, and lymphatic interactions relevant to the field of cardiac surgery will be emphasized.