Antithrombotic drug removal with hemoadsorption during off-pump coronary artery bypass grafting

BACKGROUND

Patients requiring coronary artery bypass grafting (CABG) are often loaded with antithrombotic drugs (AT) and are at an increased risk for perioperative bleeding complications. Active AT removal by a hemoadsorption cartridge integrated in the cardiopulmonary bypass circuit is increasingly used in this setting to reduce bleeding, and herein we describe the extension of this application in patients on AT undergoing off-pump coronary artery bypass (OPCAB).

METHODS

Ten patients (80% male; mean age: 67.4 ± 9.2years) were treated with ticagrelor (eight patients), rivaroxaban and ticagrelor (one patient), and rivaroxaban (one patient) prior to OPCAB surgery. AT's were discontinued one day before surgery in nine patients and on the day of surgery in one patient, and all patients were also on aspirin. The cohort mean EuroSCORE-II was 2.9 ± 1.5%. A hemoadsorption cartridge was integrated into a dialysis device (n=4) or a stand-alone apheresis pump (n=6) periprocedural, for a treatment time of 145 ± 33 min. Outcome measures included bleeding according to Bleeding Academic Research Consortium (BARC)-4 and 24-hour chest-tube-drainage (CTD).

RESULTS

Mean operation time was 184 ± 35 min. All patients received a left internal thoracic artery with a mean of 2.3 ± 0.9 total grafts. One patient had a BARC-4 bleeding event and there were no surgical re-explorations for bleeding. Mean 24-hours CTD was 680 ± 307mL. During follow-up of 19.5 ± 17.0 months, none of the patients died or required further reinterventions. No device-related adverse events were reported.

CONCLUSIONS

Hemoadsorption via a stand-alone apheresis pump during OPCAB surgery was feasible and safe. This innovative and new approach showed favorable bleeding rates in patients on antithrombotic drugs requiring bypass surgery.

A New Apheresis Device for Antithrombotic Drug Removal during Off-Pump Coronary Artery Bypass Surgery

Background and Objectives: The hemoadsorption device CytoSorb® (CytoSorbents Inc., Princeton, NJ, USA) has been shown to efficiently remove ticagrelor from whole blood in vitro. A promising clinical experience was made with the integration of the hemoadsorption cartridge on the cardiopulmonary bypass (CPB) circuit during cardiac surgery to reduce adverse events. Materials and Methods: In this report, we describe a novel approach using a new apheresis platform, PUR-01 (Nikkisio Co., Ltd., Tokyo, Japan), which was used as the extracorporeal circuit where CytoSorb® could be installed for the removal of ticagrelor during off-pump coronary artery bypass (OPCAB) procedures. Results: In a 74-year-old male (index case) with coronary artery disease and dual antiplatelet therapy, hemoadsorption was initiated with a skin incision for OPCAB surgery and was continued for 221 min to eliminate ticagrelor. The blood volume that had circulated through the CytoSorb® was 39.04 L in total. Thus far, this treatment strategy has been used in four cases with CHD and DAPT who needed OPCAB surgery. The intraoperative and postoperative courses were uneventful in all patients. No device-related adverse events occurred. Conclusions: The combination of the PUR-01 apheresis pump and hemoadsorption with the CytoSorb® column during OPCAB procedures appears to be safe and effective in eliminating antiplatelet drugs.

Sternal closure after median sternotomy: a new technique using titanium hooks and wires applied parasternally

OBJECTIVES

Osteosynthetic closure of the chest after median sternotomy is usually performed with steel wires. We describe, for the first time, a case series in which titanium hooks were implanted from the sternal surface in patients who required secondary or additional stabilization. In comparison to the classic wires, the diameters of the hooks are approximately three times bigger and therefore reduce the risk of cutting through the bones. Additionally, there is no need to dissect retrosternal adhesions, which may reduce the risk of injuring mediastinal tissues.

METHODS

The hooks are shaped like fishing hooks and can be inserted parasternally into the intercostal spaces. They can be pulled to the contralateral side of the sternum by the attached wires and then intertwined with a second hook.

RESULTS

In 13 patients, the system was used to provide additional stabilization, while in two patients the hooks were implanted for exclusive stabilization of sternal fractures. In all cases but one, the implantation was able to eliminate the sternal problems. No infections, necrosis or bleeding of neighbouring tissues occurred. One patient developed chronic sternal infection, which necessitated explantation of the hooks.

CONCLUSIONS

This sternal closure system using titanium hooks inserted parasternally is an effective alternative to conventional techniques and may increase stability of the breastbone and reduce the risk of injury to retrosternal tissues.

Partial inferior sternotomy and deep hypothermic circulatory arrest for rescue of a failed TAVI case: what does constitute 'inoperable'?

A 65-year-old male patient was considered inoperable by conventional means for a previous triple coronary artery bypass grafting with a patent in situ right internal mammary artery graft to the left anterior descending artery crossing the thorax at midline directly behind the sternum. Transcatheter aortic valve implantation failed due to loss of the prosthetic device in the left ventricular outflow tract. Mandatory conversion was accomplished by an inferior partial T-shape sternotomy and extracorporeal circulation draining from the right atrium and feeding into the right femoral artery. A conventional 27-mm aortic valve bioprosthesis was successfully implanted during deep hypothermic circulatory arrest. The patient recovered normally exhibiting no neurological or cardiocirculatory complications.

Transcatheter Edwards Sapien XT valve in valve implantation in degenerated aortic bioprostheses via transfemoral access

OBJECTIVES

Surgical treatment of degenerated aortic bioprostheses is associated with an increased risk of morbidity and mortality, especially in elderly patients with significant co-morbidities. Therefore, transcatheter aortic valve implantation (TAVI) performed as valve in valve technique appears as an attractive alternative treatment option. We report of a case series of seven patients with dysfunctional bioprosthetic aortic heart valves who have been treated with TAVI via transfemoral access.

METHODS AND RESULTS

Valve in valve implantation using the Edwards Sapien XT bioprostheses (Edwards Lifesciences LLC, Irvine, CA, USA) was performed in eight patients (3 men, 5 women, mean age 85.3 ± 6.1 years) with a high operative risk (logistic euroSCORE 27.2 ± 7.3). Six patients underwent TAVI because of high grade stenosis of the aortic bioprostheses, whereas two patients presented with high grade regurgitation. All patients suffered at least from NYHA class III dyspnea during admission. TAVI was successfully performed via transfemoral access under local anesthesia with mild analgesic medication in all cases. Mild aortic regurgitation occurred in three patients while no permanent pacemaker implantation was required. Major cardiac events or cerebrovascular events did not occur. One aneurysm spurium, with the need of one blood transfusion, occurred. All patients improved at least one NYHA class within 30 days.

CONCLUSION

TAVI for degenerated aortic bioprostheses, using the Edwards Sapien XT valve via transfemoral access is a feasible option for patients at high surgical risk.

Long-term self-management of anticoagulation therapy after mechanical heart valve replacement in outside trial conditions

In this investigation, we hypothesize that quality of oral anticoagulation (OA) and long-term outcome after mechanical heart valve (MHV) replacement with self-management (Self-M) of OA is superior to conventional anticoagulation treatment (Conv-T), even in outside trial conditions. One hundred sixty patients (78.8% aortic valve replacements) were trained in international normalized ratio Self-M and 260 patients (86.2% aortic valve replacements) preferred Conv-T. Mean follow-up was 8.6 ± 2.1 years, representing 3612 patient-years. During follow-up, 37.2% bleedings and 10.6% thromboembolic events were recorded in the Self-M group versus 39.6% bleedings (P = 0.213) and 15.4% thromboembolic events (P = 0.064) in the Conv-T group. Serious adverse events were significantly lower in the Self-M group [grade III bleeding events causing disability or death: 0 versus 4.6% (P = 0.03); grade III thromboembolic events: 0.6 versus 5.0% (P = 0.011)]. Patients with Self-M were significantly more satisfied with their OA management and their quality of life (P < 0.001). Actuarial survival after 1, 5 and 10 years was 100, 99 and 97 with Self-M and 100, 95 and 81% with Conv-T, respectively (P < 0.001). Univariate risk factors for mortality were age (P = 0.008), type of operation (P = 0.021) and conventional OA (P < 0.001). In multivariate analysis, only conventional OA reached significance (P < 0.001). We conclude that in a routine setting under outside trial conditions Self-M of OA improves long-term outcome and treatment quality.

Mid-term outcomes of patients with PCI prior to CABG in comparison to patients with primary CABG

The number of percutaneous coronary interventions (PCI) prior to coronary artery bypass grafting (CABG) increased drastically during the last decade. Patients are referred for CABG with more severe coronary pathology, which may influence postoperative outcome. Outcomes of 200 CABG patients, collected consecutively in an observational study, were compared (mean follow-up: 5 years). Group A (n = 100, mean age 63 years, 20 women) had prior PCI before CABG, and group B (n = 100, mean age 66, 20 women) underwent primary CABG. In group A, the mean number of administered stents was 2. Statistically significant results were obtained for the following preoperative criteria: previous myocardial infarction: 54 vs 34 (P = 0.007), distribution of CAD (P < 0.0001), unstable angina: 27 vs 5 (P < 0.0001). For intraoperative data, the total number of established bypasses was 2.43 ± 1.08 vs 2.08 ± 1.08 (P = 0.017), with the number of arterial bypass grafts being: 1.26 ± 0.82 vs 1.07 ± 0.54 (P = 0.006). Regarding the postoperative course, significant results could be demonstrated for: adrenaline dosage (0.83 vs 0.41 mg/h; [p is not significant (ns)]) administered in 67 group A vs 47 group B patients (P = 0.006), and noradrenaline dosage (0.82 vs 0.87 mg/h; ns) administered in 46 group A vs 63 group B patients (P = 0.023), CK/troponine I (P = 0.002; P < 0.001), postoperative resuscitation (6 vs 0; P = 0.029), intra aortic balloon pump 12 vs 1 (P = 0.003), and 30-day mortality (9% in group A vs 1% in group B; P = 0.018). Clopidogrel was administered in 35% of patients with prior PCI and in 19% of patients without prior PCI (P = 0.016). Patients with prior PCI presented for CABG with more severe CAD. Morbidity, mortality and reoperation rate during mid term were significantly higher in patients with prior PCI.

Blood type incompatible cardiac transplantation in young infants☆

OBJECTIVE

Donor organ shortage in pediatric heart transplantation (HTx) is causing mortality rates of 30-50% on the waiting list. Due to immaturity of the immune system of newborns and infants, ABO-incompatible HTx may be an option to increase donor availability. We present our experience with ABO-incompatible HTx.

METHODS

Three infants were transplanted ABO-incompatible since 12/2004: (1) hypoplastic left heart complex, (2) restrictive hypertrophic cardiomyopathy, (3) dilative cardiomyopathy. Age at HTx was 7, 5, and 3.5 months. All recipients had blood type O, donors were A, A, and B. Informed consent was given by parents, the ethics committee, and Eurotransplant.

RESULTS

Preoperative isohemagglutinin titers were low (Patient 1: 1:4 for anti-A1, A2, B, Patient 2: 1:4, 1:1, 1:4 for anti-A1, A2, B, respectively, and Patient 3: 0 for all, but quick spin 1+ for all). Intraoperatively, plasma was separated from red blood cells and discarded up to six times until antibodies were eliminated. Immunosuppressive induction with ATG was started for 5 days. Basic immunosuppression consisted of tacrolimus, mycophenolate mofetil, and prednisone. Extubation was performed on days 15, 2, and 1, respectively. After a follow-up of 17, 16, and 12 months all patients are well, ventricular function is excellent without any acute rejection periods; Patient 1 is still on dialysis. Isohemagglutinin titers against donor blood type have disappeared in follow-up.

CONCLUSIONS

ABO-incompatible cardiac transplantation shows good short-term results in young infants and seems to be a safe procedure to lower the mortality on the waiting list.

Coagulation factor XIII reduces postoperative bleeding after coronary surgery with extracorporeal circulation

BACKGROUND

One cause of diffuse bleeding after cardiac operations may be a low plasma concentration of coagulation Factor XIII, which is essential for coagulation but is not covered by standard coagulation monitoring.

PATIENTS AND METHODS

In a prospective, randomized, double blinded study, 2500 units, 1250 units, and a placebo were administered in groups of 25 patients each, immediately after administration of protamine. Postoperative amount of blood loss and blood transfusion was recorded.

RESULTS

Patients were not statistically different with respect to the course of plasma levels of Factor XIII until administration of the study drug. In all groups Factor XIII fell from preoperative normal values to subnormal values after extracorporeal circulation. After administration of the study drug, Factor XIII increased to 71 %, 85 %, 103 % in the placebo, 1250 units, and 2500 units group, respectively, and these differences were statistically significant ( p < 0.05). Postoperative blood loss was lowest in the 2500 units group and highest in the placebo group, however this was not significantly different. There was also no significant difference in the amount of blood transfusion. After differentiating all patients according to their post medication Factor XIII level into two groups with levels of < 70 % and > or = 70 %, postoperative blood loss was found to be significantly higher in the < 70 % group as was the amount of blood transfusions.

CONCLUSIONS

Factor XIII administration reduces postoperative blood loss and the extent of blood transfusion after coronary surgery, however administration is only helpful if plasma levels are below the normal value. Measurement of plasma levels is recommended before Factor XIII substitution.

Mechanical Circulatory Support in Infants and Adults With the MEDOS/HIA Assist Device

Mechanical circulatory support is successfully applied to patients with low cardiac output. The MEDOS/HIA-System provides pulsatile ventricular assistance for pediatric and adult patients. Our experience with 13 consecutive patients with the MEDOS is reported. Perioperative survival was 84.6%, complications occurred in 61% (31% thrombembolism, 23% rethoracotomy, 7% infections). Mean duration of support was 17.6 +/- 14.6 days (1-45 days). Bilirubin decreased from 3.9 +/- 2.3 to 2.7 +/- 1.6 mg/dL; creatinine from 1.6 +/- 1 to 1.4 +/- 0.8 mg/dL; lactate from 5.8 +/- 4.2 to 1.7 +/- 1.5 (P = 0.027; Wilcoxon). All patients who underwent subsequent heart transplantation (6 of 13; 46%) were discharged from hospital. For 38.5% of the patients no organ offer was received. Mechanical circulatory support with the MEDOS/HIA-System can be performed successfully for bridging to transplantation. Secondary organ functions improve under this pulsatile circulatory assistance. Hemorrhage and thromboembolic events are the most frequent complications.

Mechanical Circulatory Support in Pediatric Patients with the MEDOS Assist Device

Mechanical circulatory support is successfully applied to patients with low cardiac output. The MEDOS-System provides pulsatile ventricular assistance for patients of all age groups, including neonates. We report our experience with seven consecutive pediatric patients with the MEDOS-VAD. The indication was bridge to transplantation in all patients. Mean age was 7.3 +/- 6.5 years (range 0.75-16.9 years) and mean weight was 26.3 +/- 21.7 kg (range 5.9-60 kg). Perioperative survival was 100%; complications occurred in six patients (86%; two cerebral embolism/bleeding, two rethoracotomy, two exchange of pump chamber due to thrombus formation after 4 and 9 days). Mean duration of support was 20.4 +/- 10.8 days (range 6-38 days). Bilirubin decreased from 3.5 +/- 2.6 mg/d to 2.1 +/- 1.2 mg/d. Hospital mortality was three of seven patients who did not receive an organ offer in time. All patients who underwent subsequent heart transplantation (four of seven patients; 57%) were discharged from the hospital. Mechanical circulatory support with the MEDOS-System can be performed successfully in pediatric patients of any age. Secondary organ functions improve under this pulsatile circulatory assistance. Hemorrhage and thromboembolic events are the most frequent complications.

Surgical epicardial left ventricular lead versus coronary sinus lead placement in biventricular pacing☆

OBJECTIVE

Biventricular pacing has demonstrated improvement in cardiac function in treating congestive heart failure (CHF). Two different operative strategies (coronary sinus vs. epicardial stimulation) for left ventricular (LV) pacing were compared.

METHODS

Since April 1999, a total of 86 patients (pts, age: 63+/-10 years) with depressed systolic LV function (mean ejection fraction 24+/-9%), left bundle-branch-block (mean QRS 182+/-22 ms) and congestive heart failure NYHA III or higher were enrolled. For biventricular stimulation coronary sinus (CS) leads were placed in 79 pts. Nine of these devices were converted to surgical epicardial LV-leads, because of CS-lead failure. In 7 patients epicardial LV-leads were initially implanted surgically, accounting for a total of 16 pts with surgical placed epicardial steroid-eluting LV-leads. For these, a limited left-lateral thoracotomy (7+/-4 cm) was used. Thirty-three (38%) pts had an indication for a defibrillator. The mean follow-up time was 16.4+/-15.4 months (0.1-45 months), representing 107.1 patient-years.

RESULTS

In the biventricular pacing mode, QRS duration decreased to 143+/-16 ms (P<0.001). Threshold capture of the CS-leads increased significantly compared to surgically placed epicardial leads (18 month control: 2.2+/-1.4V/0.5 ms vs. 0.7+/-0.3V/0.5 ms), which had no increase in threshold (P<0.001). At the 18 month follow-up 7 CS-leads had a threshold of >4V/0.5 ms vs. epicardial leads which were under 1.1V/0.5 ms, except for one (1.8V/0.5 ms). After CS-lead implantation 25 LV-lead related complications occurred, (failed implantation, CS-dissection, loss of pacing capture, diaphragm stimulation or lead dislodgment), vs. one dislodgement after surgical epicardial lead placement (P<0.05). Correct lead positioning (obtuse marginal branch area) was achieved in all surgical epicardial placements but only in 70% with CS-leads (P<0.03). In the follow up period, 9 pts died (4 cardiac related). Heart transplantation was necessary in 4 pts due to deterioration of the cardiomyopathy.

CONCLUSIONS

Surgical epicardial lead placement revealed excellent long-term results and a lower LV-related complication rate compared to CS-leads. Although, the approach via limited thoracotomy for biventricular pacing is associated with 'more surgery', it is a safe and reliable technique and should be considered as an equal alternative.

Port-a-Cath complicated by right atrial thrombus

Right atrial thrombosis during chemotherapy is commonly treated conservatively. We describe a minimally invasive surgical procedure to remove a right atrial thrombus in a patient with a history of recurrent lung embolism. Surgery was performed through a mini-thoracotomy without cardiopulmonary bypass during occlusion of both caval veins. Recovery was uneventful.

Optimizing use of the octopus system for off-pump total arterial myocardial revascularization with the TY graft

Rapid developments in interventional cardiology for the treatment of coronary artery disease ask for further evolution of surgical revascularization techniques with improved short-term and long-term results. Off-pump bypass grafting, total arterial revascularization, and use of composite arterial grafts are innovative operative procedures that are already established in many centers. We describe our technique to combine all three procedures in a single operation.

Surgical treatment of permanent atrial fibrillation using microwave energy ablation: a prospective randomized clinical trial

OBJECTIVE

Radiofrequency or the use of microwave energy in combination with atrial size reduction during open heart surgery have been reported to be effective in up to 75% in the treatment of permanent atrial fibrillation. However, no data from prospective randomized trials using microwave energy are available.

METHODS

Forty-three patients with permanent atrial fibrillation undergoing open-heart surgery were randomly stratified into treatment group receiving microwave ablation and atrial size reduction (n=24) or control group (n=19). Patients in either group were treated with amiodarone or sotalol for 3 months if sinus rhythm or any atrioventricular rhythm was successfully restored. Follow-up time points were at 3, 6 and 12 month after surgery.

RESULTS

In the treatment group 22 out of 24 patients (91,7%) were successfully converted to sinus rhythm by using intraoperative microwave ablation therapy whereas only six out of 19 (31.5%) patients converted to sinus rhythm directly after surgery. At 12-month follow-up there were still a significantly higher percentage of patients in the treatment group free from atrial fibrillation when compared to control (80 vs. 33.3%, P=0.036).

CONCLUSION

The preliminary data from this first prospectively randomized trial indicate that microwave ablation combined with atrial size reduction is a safe and highly efficient treatment in permanent atrial fibrillation.

Midterm results of beating heart surgery in 1-vessel disease: minimally invasive direct coronary artery bypass versus off-pump coronary artery bypass with full sternotomy

BACKGROUND

Off-pump cardiac surgery is becoming an established method of surgical revascularization. However, performing anastomoses on a beating heart can be challenging, especially through small incisions. We compared our midterm results in patients with 1 vessel disease using full sternotomy (OPCAB) or a left anterior minithoracotomy (MIDCAB).

METHODS

At our institution between December 1996 and December 1998, 102 patients (OPCAB, n = 45, MIDCAB, n = 57); age, 61 +/- 11 years; 69% men with 1-vessel disease of the left anterior descending coronary artery (LAD) underwent off-pump myocardial revascularization through the left internal thoracic artery (LITA). In the OPCAB group 17 (37.8%) of the patients received an additional vein graft to a diagonal branch. OPCAB was generally preferred in obese or high-risk patients or patients with a long LITA-LAD distance (>7 cm) on an electron beam computed tomography of the chest.

RESULTS

Operative mortality was 0. Time of surgery (169 +/- 48 versus 197 +/- 45 minutes) and coronary artery occlusion time (19 +/- 7 versus 23 +/- 6 minutes) were significantly lower (P = .004 and P = .009) in the OPCAB group. MIDCAB surgery was related to a higher incidence of occluded (4 versus 0; P = .039) or stenosed (7 versus 2; P = .06) anastomoses and necessity for immediate reintervention (9 versus 0; P = .023). During a mean follow-up period of 5.2 years, MIDCAB patients (6 MIDCAB patients versus 1 OPCAB patient) tended to need more coronary interventions and develop more recurrent angina (23 MIDCAB versus 12 OPCAB patients). Two OPCAB patients died during the follow-up period.

CONCLUSIONS

Our initial experience in beating heart surgery demonstrated that MIDCAB is technically more challenging than OPCAB. MIDCAB procedures should therefore be performed by experienced surgeons on selected patients. Midterm results after OPCAB procedures tend to a lower rate of adverse cardiac events.

Epicardial lead implantation techniques for biventricular pacing via left lateral mini-thoracotomy, video-assisted thoracoscopy, and robotic approach

PURPOSE

For optimal biventricular pacing, the left ventricular (LV) lead has been found to be best placed in the area where optimal concordance is achieved between the LV pacing site and the site of the most delayed LV wall. For anatomical or technical reasons, the placement of the LV lead via the coronary sinus at the intended target area of the LV is often not possible. An option for avoiding these drawbacks is the surgical implantation of the LV lead under direct vision. This report describes 3 epicardial lead implantation techniques that are less invasive.

METHODS

In 80 patients with advanced heart failure and left bundle branch block, epicardial LV leads for biventricular pacing were implanted with 3 different methods: (1) left lateral mini-thoracotomy; (2) a video-assisted thoracoscopy approach using lead implantation tools; and (3) a robotically enhanced telemanipulation system. Video films are provided for all 3 techniques in The Heart Surgery Forum online.

RESULTS

Independent of the surgical techniques, the intended lead location on the LV was achieved in all patients. Acute and 3-month LV lead thresholds were satisfactory in 79 patients (99%). Two lead displacements were observed. One thoracotomy was carried out after thoracoscopic lead placement because the patient developed an early exit block. Five patients who underwent an operation with the robot needed a conversion to thoracotomy because of technical failure of the robot (2 patients) or massive pleural adhesions (3 patients). There were no severe adverse events related to any technique. Three patients died in the hospital from the progression of end-stage heart failure.

CONCLUSION

Epicardial lead implantation for biventricular pacing is feasible with all 3 surgical techniques. Each method allows optimal lead implantation under direct vision and therefore reduces the incidence of nonresponders resulting from suboptimal lead placement.

Reduction of systemic and cardiac adhesion molecule expression after off-pump versus conventional coronary artery bypass grafting

Cardiopulmonary bypass (CPB) and operative trauma are associated with increased expression of proinflammatory mediators. We determined the relative contribution of CPB on activation of cytokines and adhesion molecules in patients undergoing coronary revascularization by comparing them with patients receiving off-pump coronary artery bypass grafting (OPCAB). Twenty-six patients were assigned to either the OPCAB procedure using a suction device and regular sternotomy (n = 13), or were treated conventionally using extracorporeal circulation, blood cardioplegia, and hypothermic arrest (29 degrees C-31 degrees C; n = 13). Systemic levels of TNF-alpha and the soluble adhesion molecules P-selectin and intracellular adhesion molecule 1 (ICAM-1) were assayed. Immunohistochemistry was used to account for cardiac-specific expression of adhesion molecules in interventricular endomyocardial sections. Both systemic and endomyocardial expression of adhesion molecules were lower in the OPCAB group. Coronary revascularization with CPB resulted in a significant higher expression of TNF-alpha, which was associated with P-selectin and ICAM-1 expression. This was accompanied with higher catecholamine requirement in the CPB group in the early postoperative period. Despite comparable surgical trauma, the OPCAB procedure without the use of CPB and cardioplegic arrest significantly reduces systemic and cardiac adhesion molecule expression and catecholamine requirement. Since the clinical course in the early postoperative period was comparable, larger trials are required to select the appropriate patient who benefits most from one or the other treatment regime.

Clinical relevance of intracranial high intensity transient signals in patients following prosthetic aortic valve replacement

OBJECTIVES

There has been frequent report on transcranially detected microembolic signals (HITS) following cardiac surgery using extracorporeal bypass support. The clinical relevance of HITS, however, has yet to be clarified. The incidence of thromboembolic events is increased following mechanical heart valve replacement. The purpose of this study was to quantify postoperative HITS after implantation of two types of prosthetic aortic valves and to compare both types of mechanical valves with respect to the generation of HITS. In addition, HITS rates were correlated with clinical, echocardiographical and laboratory findings.

METHODS

Forty-two patients following implantation of either a Sorin Biomedica heart valve (n=22, group A) or a Tekna Duromedics mechanical valve (n=20, group B) were examined. A group of ten healthy volunteers served as control. Clinical, echocardiographic, carotid artery duplex and laboratory examinations were performed in all patients. A 60 min bilateral transcranial doppler monitoring of the medial cerebral artery (MCA) was also carried out in order to evaluate cerebral blood flow.

RESULTS

In group A 14 of 22 patients were positive for HITS (53%), with an average of 16.4+/-19 HITS/pt.h. In group B 15 of 20 patients were HITS positive (75%) with an average amount of 14.4+/-24 HITS/pt.h. The incidence of HITS was not significantly different between the two groups. No correlation was seen between the HITS-rate/h and neurological findings, duplex sonographic results, mechanical valve size and anticoagulation regimen (P>0.05). However, a negative correlation was observed between patient age and HITS-rate (P=0.02) as well as between the NYHA degree and HITS-rate (P=0.018). The HITS-rate also correlated with postoperative time (P=0.042). No HITS were detected in the control group.

CONCLUSIONS

HITS do not correlate with the individual clinical status and, thus, cannot predict the occurrence of neurological deficits in patients following mechanical aortic valve implantation.

[Only for limited indications. Biventricular pacemaker improves severe heart failure]

In patients with congestive heart disease in whom left ventricular dilatation is associated with severely disordered contraction due to delayed ventricular conduction, a new form of treatment not requiring drugs is currently becoming established--biventricular pacing. Via an implanted electrode, biventricular stimulation accelerates conduction in the left ventricle and resynchronizes its contraction. Patients being considered for such therapy must have stable stage III disease (NYHA classification) under optimal medication, and a left bundle branch block with a QRS of at least 150 ms. Definitive recommendations with regard to indications will be possible only when current randomized mortality studies have been concluded.

Re-OPCAB vs. Re-CABG for myocardial revascularization

BACKGROUND

The present study compared redo coronary artery bypass grafting (Re-OPCAB) techniques with conventional redo coronary artery bypass grafting (Re-CABG) with particular focus on myocardial damage and clinical outcome parameters.

METHODS

Redo OPCAB (Re-OPCAB) was performed on 20 consecutive patients (15 males, mean age 63.2 +/- 9.3 years) using either the anterolateral approach for minimally invasive direct coronary artery bypass (n = 4) or the Octopus technique with regular sternotomy (n = 16). The Re-CABG group consisted of 20 consecutive patients (18 males, mean age 67.1 +/- 6.6 years). Groups did not differ in the number of atherosclerotic risk factors, or left ventricular, renal or liver function.

RESULTS

Duration of surgery, number of bypass grafts and amount of transfused red blood cells did not differ significantly between both groups. Requirement of epinephrine (mg/h) within the first 24 h was lower in the Re-OPCAB group (Re-OPCAB: 0.14 +/- 0.22 vs. CABG: 0.88 +/- 0.97; p<0.01). In addition, CKMB levels at 24 h after operation were lower in the Re-OPCAB group (Re-OPCAB: 10.0 +/- 10.1 vs. Re-CABG: 38.7 +/- 28.1 U/l, p<0.001). There were no acute myocardial infarctions or deaths in the perioperative period. In the CABG group, there was a longer time period to extubation (hours) (Re-OPCAB: 9.8 +/- 3.9 vs. Re-CABG: 28.7 +/- 25.5; p<0.001), and the length of ICU stay was significantly prolonged (OPCAB: 1.3 +/- 0.5 versus Re-CABG: 4.4 +/- 8.7; p<0.001). The graft patency rate at follow-up was 95% in the Re-OPCAB group.

CONCLUSION

Re-OPCAB results in decreased cardiac specific enzyme release, reduced requirement of inotropes and comparable clinical outcome in the early postoperative period. It is an appropriate alternative to conventional Re-CABG in selected patients awaiting reoperation for myocardial revascularization. Larger prospective and randomized trials are required to select the appropriate patient who benefits most from one or the other treatment regime.

[Minimally invasive procedures in heart surgery. How does it work and who profits?]

The leading minimally invasive procedures employed in coronary surgery are minimally invasive direct coronary arterial bypass surgery (MIDCAB) and the Octopus system. These interventions are performed on the beating heart and require no extracorporeal circulation (ECC), thus avoiding the side effects, such as pulmonary or neurological complications, associated with ECC. In surgery on the mitral or aortic valve, the procedures are carried out via small incisions in the non-beating heart, and endovascular bypass systems (e.g. Port-Access) are sometimes needed for EEC. The advantages of small incisions are a reduction in the risk of infection, shorter hospital stay and, in particular, improved cosmesis. A disadvantage is the longer operating time. Only careful patients selection guarantees successful surgery.