[Ventricular long-term support with implantable continuous flow pumps: on the way to a gold standard in the therapy of terminal heart failure]. / Ventrikuläre Langzeitunterstützung mit implantierbaren kontinuierlichen Flusspumpen : Auf dem Weg zum Goldstandard in der Therapie der terminalen Herzinsuffizienz.

Mechanical circulatory support nowadays represents an important option in the treatment of patients with advanced heart insufficiency. Once developed as a bridging to heart transplantation, it is now a valuable option for permanent support in patients for whom a heart transplantation is not possible due to contraindications or a lack of available organs. Furthermore, it can be used as a bridging to myocardial recovery and explantation. The number of implantations of left ventricular assist devices (LVAD) has clearly increased in recent years and approximately one half of these implantations is already carried out in centers not specialized in transplantations. This development necessitates that every practicing physician is aware of the basic principles of mechanical circulatory support and with the possible complications. This article gives a summary of the current state of the technology and treatment of patients with long-term VADs.

Argatroban anticoagulation for heparin induced thrombocytopenia in patients with ventricular assist devices.

BACKGROUND: Patients receiving implantation of ventricular assist devices (VAD) suffer a high incidence of heparin induced thrombocytopenia (HIT); the occurrence of this condition is associated with increased complications and worse outcomes. We report our experience in the management of patients who were diagnosed with HIT either before (HITpre) or after (HITpost) implantation of VAD with argatroban, a direct thrombin inhibitor. METHODS: This retrospective analysis assessed data of VAD patients diagnosed with HIT at Deutsches Herzzentrum Berlin between November 2005 and April 2009. Argatroban dose requirements, anticoagulation efficacy and adverse events (death, thromboembolism, bleeding) were recorded. Procedural success (discharge from the hospital, heart transplantation, or recovery of the failing heart) was also assessed. RESULTS: Twenty-seven patients were identified (11 HITpre, 16 HITpost). Argatroban was effective in obtaining adequate anticoagulation with a reduced dose regimen (0.02-0.42 mcg/Kg/min starting dose; 0.02-1.5 mcg/Kg/min maintenance dose). We noted 5 thromboembolic complications (18%), 6 cases of major bleeding (22%) and 5 deaths (18%), all cause composite adverse end point occurring in 40% of patients. Procedural success was obtained in 81% of patients (92% HITpre, 69% HITpost). As compared to historical controls of patients treated with lepirudin in the period 2000-2005, results were significantly improved. CONCLUSION: Argatroban anticoagulation is feasible in patients with HIT after VAD implantation, without increasing bleeding risk. Its impact in terms of survival should be reviewed also in the light of the technological improvements of assist devices.

[Improvements in implantable mechanical circulatory support systems : literature overview and update]. / Fortschritte bei implantierbaren mechanischen Kreislaufunterstüzungssystemen : Literaturübersicht und Update.

In recent years, ventricular assist devices (VAD) supporting the left (LVAD), the right (RVAD) or both ventricles (BVAD) have rapidly emerged as the standard of care for advanced heart failure patients. Both the numbers and ages of patients in which they are used are rising worldwide, especially when used as a permanent support (bridge to destination, BTD). Due to the continuing lack of donor organs, these devices now represent a viable alternative to bridge patients to transplantation (BTT), with a 1-year survival rate of 86%. BTD, especially in long-term support, might be a valid, and the sole, option for those patients in whom heart transplantation is contraindicated. Patient selection, pre- and intra-operative preparation, as well as the timing of VAD implantation are important factors critical to successful circulatory support. While BTT remains the goal in the majority of patients, the number of permanent VADs (i. e. BTD) is rising significantly. Although explantation of a VAD system as a bridge to recovery (BTR) can be considered in only a small number of patients, it represents a very special part of this therapy modality.

Bivalirudin anticoagulation during cardiac surgery: a single-center experience in 141 patients.

The feasibility of bivalirudin for anticoagulation during cardiac surgery has been confirmed in four multicenter clinical trials. Here, we report our single-center experience with bivalirudin anticoagulation in "on-pump" and "off-pump" cardiac surgery in a large number of patients with and without heparin antibodies. Data of patients who underwent cardiac surgery with bivalirudin anticoagulation between 06/2003 and 12/2007 at our institution were reviewed. Assessment included procedural success, blood loss, transfusion requirements, re-exploration rates and drug-related complications during the procedures. There were 141 patients treated with bivalirudin, of whom 40 had heparin antibodies. In 26 patients, "off-pump" coronary artery bypass grafting was performed and the remaining 115 patients had surgery with cardiopulmonary bypass (CPB). The procedural success rate after 7 days and after 30 days was 99.4%. The mean blood loss after "off-pump" surgery was 833 +/- 310 ml, with a transfusion rate of 30%. The mean blood loss after "on-pump" surgery was 750 +/- 494 ml, with a transfusion rate of 56%. Two patients needed re-exploration due to persistent hemorrhage. Overall transfusion rates were increased in patients with heparin antibodies. The current investigation demonstrates that, in experienced hands, bivalirudin anticoagulation can be performed with excellent procedural success and low complication rates during "on-pump" and "off-pump" cardiac surgery. Recent problems associated with the production of heparin have emphasized the urgent need for an alternative for use beyond the limited indication of heparin-induced thrombocytopenia.

Early clinical experience with the E-vita thoracic stent-graft system: a single center study.

AIM: The aim of this study was to evaluate the safety and efficacy of a new endovascular thoracic stent-graft, which was designed to overcome the restrictions of previously used stent-grafts. METHODS: Between May 2004 and March 2008 a prospective evaluation was conducted in 126 consecutive patients (71% men; age 64 [19-86] years). A total of 138 implantations were performed. E-vita stent-grafts were implanted for type-B dissection (N.=56), degenerative aneurysm (N.=25), penetrating aortic ulcer (N.=17), blunt traumatic lesions (N.=10), mobile atheroma (N.=1), suture aneurysms (N.=7) and revisionary surgery following previous endograft implantation (N.=22). All patients eligible for stent-grafting were treated with this system regardless of their clinical status and aortic pathology. The percentage of emergency procedures was 52% (N.=72). Per implantation a mean of 1.3 segments was implanted with an effective total covered length of the aorta of mean 204 mm, median 230 mm (0-450 mm). In 32 of 39 cases with more than one segment, the entire descending aorta was included in the procedure. RESULTS: The 30-day mortality rate was 12.3% (17 patients). All deaths but one were in the group of emergency surgery patients. This results in mortality of 1.5% in the elective and 22% in the emergency procedures. Reversible procedure-induced spinal cord ischemia was observed in 2 cases. Stroke occurred in 2.8% (4 patients). Primary technical success was rated at 77 % (106 procedures) and secondary success at 89 % (124 procedures). CONCLUSION: All forms of thoracic aortic disease can be treated with this new stent-graft. It has proved particularly valuable in cases of difficult conditions in the aortic arch and extended aneurysms. In particular, it is possible to cover the entire thoracic aorta with two or three stent-graft segments, thus considerably reducing the number of connections.

Preexisting atrial fibrillation as predictor for late-time mortality in patients with end-stage renal disease undergoing cardiac surgery--a multicenter study.

BACKGROUND: Although patients with end-stage renal disease (ESRD) are considered to be high-risk patients in cardiac surgery, the reported studies are rather small, resulting in unsatisfactory analyses of outcome determinants. Therefore, we aimed to identify possible risk factors, with a particular focus on the impact of pre-existing atrial fibrillation (AF) on the postoperative short-term and long-term mortality of ESRD patients undergoing cardiac surgery. METHODS: In a multicenter study 522 patients with ESRD undergoing CABG only (62.9 %), valve surgery only (17.2 %), or both (19.9 %) with comparable demographic and other cardiac risk factor characteristics were investigated retrospectively over a period of 10 years. The outcome was divided into perioperative (within 30 days) and late morbidity and mortality, and multivariate analysis was performed for both. RESULTS: The mean perioperative mortality was 11.5 % and the 5-year survival rate was 42 %. Emergency surgery, insulin-dependent diabetes mellitus, the number of vein grafts and age were identified as risk factors whereas complete revascularization, the use of an internal thoracic artery and the presence of sinus rhythm were identified as beneficial factors for long-term survival. 14.1 % of all patients had pre-existing AF. Although AF was not identified as an independent risk factor for perioperative mortality ( P = 0.59), it was identified as an independent predictor for late mortality ( P < 0.001). Median survival of patients without AF was 1816 days, while for patients with AF it was only 715 days. CONCLUSIONS: AF does represent an independent predictor for long-term but not perioperative mortality in patients with ESRD. However, effective treatment of AF is controversially discussed. Anticoagulation therapy or perioperative ablation of the arrhythmia should be considered in order to improve the survival of these patients.

Coronary surgery in patients requiring chronic hemodialysis.

BACKGROUND: In uremic patients coronary surgery and the entire perioperative management is demanding. METHODS: We analyzed retrospectively data from all patients requiring chronic hemodialysis who under went coronary artery bypass grafting (CABG) between January 1 2001 and December 31 2004 at the Deutsches Herzzentrum Berlin and compared them to those of a randomized nonuremic control group (n = 68), which consisted of patients who underwent CABG during the same period. RESULTS: During the study period 6315 patients underwent coronary artery bypass grafting at the Deutsches Herzzentrum Berlin. Among these patients, we identified 71 chronic dialysis patients (1.12%). Among dialysis patients, we recorded a perioperative mortality of 5.6%. One-year survival rate was 87.7% among uremic patients and 91.0% in the control group; the corresponding 4-year survival rates were 56.7 and 88.0%, respectively. The incidence of peripheral artery disease was significantly higher in the dialysis group. Uremic patients showed significantly lower hemoglobin serum levels at the time of admission compared to the control group (11.4 +/- 1.62 vs. 13.3 +/- 1.81 mg/dl). These patients received significantly higher numbers of blood transfusions (6.7 +/- 5.6 vs. 2.75 +/- 3.8), and platelet transfusions. CONCLUSION: Our preliminary study indicates that coronary surgery can be performed with acceptable mid-term results when the specific requirements of this patient group are taken into account.

[Coronary artery bypass grafting in patients with highly impaired ventricular function. Long-term outcome]. / Koronarbypassoperation bei hochgradig eingeschränkter Ventrikelfunktion - Langzeitergebnisse.

BACKGROUND AND OBJECTIVE: Left ventricular function is the most important predictor of survival in patients with coronary artery disease. It is also an important indicator for hospital mortality after operation for end-stage coronary artery disease. In our study we investigated, how preoperative ventricular dysfunction influences long term survival after coronary bypass surgery. PATIENTS AND METHODS: Between 4/1986 and 12/2000, 1751 patients (1440 men/311 women) with left ventricular ejection fraction (LVEF) 10-30% underwent coronary bypass grafting (CABG) at the Deutsches Herzzentrum Berlin. The age of the patients was calculated to an average of 59,2 years. The prime criterion for CABG was ischemia ("hibernating myocardium") diagnosed by myocardial scintigraphy, echocardiography and in some cases with magnetic resonance imaging and positron emission tomography. RESULTS: Operative mortality for the group was 7,1%. The actuarial survival rate was 87,6% after 2 years, 76,0% after 5, and 53,3% after 9. 455 had LVEF 10-20%, in these actuarial survival was 79,8% after 2 years, 63,0% after 5 and 45,7% after 9 years. CONCLUSION: We conclude that CABG can be used successfully to improve life expectancy of patients with end-stage coronary artery disease. CABG leads to acceptable prognosis for these high-risk patients when the myocardium is preoperatively identified as being viable.

Risk stratification scores for predicting mortality in coronary artery bypass surgery.

BACKGROUND: Four risk-stratification scores (RSSs - Euro, French, CCS/Higgins, Parsonnet) were tested as predictors of mortality in coronary artery bypass grafting (CABG) surgery. METHODS: From March to April 2000, the perioperative courses of 245 consecutive CABG patients were compared to the predictions according to the RSSs. Sensitivity and specificity were determined with receiver operating characteristics (ROC) curves. RESULTS: CCS/Higgins uses the most easily acquired patient data, and rates emergency conditions as high-risk. Euro focuses on advanced age and septal rupture. French uses the smallest number of patient parameters and rates rare critical situations as high-risk. Parsonnet is partially based on the physician's subjective assessment of a "catastrophic state," making the scoring arbitrary. All RSSs gave similar (not significant) areas under the ROC curves regarding mortality (Euro 0.826 +/- 0.080, French 0.783 +/- 0.094, CCS/Higgins 0.820 +/- 0.060, Parsonnet 0.831 +/- 0.042). Predicted risk levels for the 11 patients who died differed between the RSSs--Higgins placed these patients in 3 of 5 risk levels with ascending distribution. The other RSSs placed these patients in the highest risk level except for one and two patients, respectively, who were placed in the lowest Euro and French risk level. Euro and Parsonnet placed about half of all patients with non-lethal outcome in the highest risk level. CONCLUSIONS: All RSSs satisfactorily estimated the group risk for mortality. No RSS expressed sufficient validity to predict individuals with lethal outcome. In clinical use, CCS/Higgins proved the most practicable.

Extent of myocardial tissue damage during transmyocardial laser revascularization with the CO2 Heart Laser.

OBJECTIVE AND BACKGROUND: Transmyocardial laser revascularization (TMR) is the only surgical treatment for patients with severe diffuse coronary artery disease, who are not candidates for bypass grafting or percutaneous angioplasty. However, vaporization of tissue during the creation of channels leads to a certain loss of viable myocardium during every TMR procedure. METHODS: We analyzed serum levels of creatine kinase and creatine kinase MB subtype in 163 patients after sole TMR with a CO2 laser (wave length 10.6 microm, 800-watt power). The control group consisted of 35 consecutive CABG patients and 30 consecutive redo-CABG patients. Additionally, in the TMR group we measured echocardiographically the left ventricular ejection fraction before and after TMR. We recorded the total amount of laser energy applied, average and maximum energy per channel, and the number of created channels, in order to calculate the correlation between these parameters and postoperative enzyme levels or changes in the LVEF. RESULTS: After TMR, we measured higher creatine kinase levels compared to those in CABG patients (607.8+/-558.4 U/L vs. 285.0+/-292.3 U/L, p < 0.01). The relative proportion of CK-MB of total CK, however, was significantly lower after TMR, compared to that of the control group (4.5+/-3.0% vs. 10.1+/-6.4%, p < 0.01). Patients with a pronounced postoperative increase in CK-MB levels or a higher percentage of CK-MB of total CK also after TMR operations show a decline in left ventricular contractility. In the laser group, the maximum enzyme levels were detected significantly later than in the control group (25.0+/-19.4 h postoperatively vs. 8.7+/-9.1 h, p < 0.01). There was no significant correlation between the technical laser parameters or the number of created channels and the percentage of CK-MB of total CK or changes in left ventricular ejection fraction. CONCLUSIONS: CO2 laser TMR does not result in significant injury to the myocardium. Cardiac enzymes play an important role in the detection of perioperative myocardial infarction in TMR patients.

Predictors of survival 1 hour after implantation of an intra-aortic balloon pump in cardiac surgery.

From July 1996 to March 2000, 391 patients with intraoperative cardiac low-output syndrome who underwent surgery with heart-lung bypass and had an intra-aortic balloon pump (IABP) implanted were analyzed in a prospective study. Of these 391 patients, 153 (39%) were operated on in an emergency situation, and 238 (61%) patients had elective surgeries. The perioperative mortality was 34% (133 patients). Clinical parameters were analyzed 1 hour after IABP support began. Statistical multivariate analysis showed that patients with an adrenaline requirement higher than 0.5 microg/kg/min, a left atrial pressure higher than 15 mmHg, output of less than 100 mL/hour, and mixed venous saturation (SvQ2) of less than 60% had poor outcomes. Using this data, we developed an IABP score to predict survival early after IABP implantation in cardiac surgery. We conclude that the success or failure of perioperative IABP support can be predicted early after implantation of the balloon pump. In patients with low-output syndrome despite IABP support, implantation of a ventricular assist system should be considered.

Risk scores currently used in German heart surgery.

BACKGROUND: Risk scores (RS) in heart surgery assess mortality and morbidity and mirror the degree of severity of disease of the patients when presented for surgery. We examined the use and dissemination of RS in Germany. MATERIAL AND METHODS: Our survey included 79 German heart surgery institutes in Fall 1999 and Winter 2000. RESULTS: Four institutes did not respond. Out of 75 (ad 100 %) responders 56 (75 %) institutes did not use RS, 17 (22 %) institutes used one RS method and 2 (3 %) institutes used two RS methods. The most frequently applied RS methods were the Cleveland Clinic Score and the Euro Score (n = 7, each) followed by institution-specific, internally developed RS methods (n = 5), Parsonnet's RS (n = 1) and the RS from the STS database (n = 1). Fourteen institutes used RS for internal quality control. Of these, 2 institutes publish their RS data for external quality control. The patient-related individual procedure risk was used in 6 institutes. CONCLUSIONS: A quarter of the German heart surgery institutes use one or more RS methods. The most commonly used were the Cleveland Clinic Score and the Euro Score, followed by internally developed RS methods. RS methods were most frequently used for internal quality control. The degree of the severity of disease of the patients who presented for surgery could only be compared between a small number of institutes using the same RS.

Transmyocardial laser revascularization in ischemic cardiomyopathy.

BACKGROUND: In ischemic cardiomyopathy (left ventricular ejection fraction [LVEF] < or = 30%), myocardial revascularization by coronary artery surgery has better results than heart transplantation, provided there is sufficient ischemic but viable myocardium. The mode of action of transmyocardial laser revascularization (TMR) is still being debated, but if the procedure induces improved myocardial perfusion it could be a "bridge," or alternative, to heart transplantation. METHODS: We retrospectively analyzed 194 patients, who underwent TMR between July 1997 and October 1999. Patients with TMR as an adjunct to coronary artery surgery (n = 30) and those who did not provide written consent to the procedure (n = 8) were excluded; 126 patients had normal or moderately reduced left ventricular function, and 30 patients with ischemic cardiomyopathy (LVEF < or = 30%) were included. RESULTS: After 12 months, the Canadian Cardiovascular Society (CCS) score dropped significantly from 3.6 (3 to 4) to 2.4 (1 to 4) and maximum work load increased significantly from 58 W (25 to 100 W) to 73 W (25 to 120 W). However, thallium score and LVEF did not improve significantly (27% [15% to 30%] to 32% [15% to 45%]). Prior to the TMR procedure, all 30 patients had a "low risk" or "medium risk" of death according to the Aaronson classification. The 30-day, 1-year, and 2-year survival rates were 83%, 50%, and 47%, respectively. CONCLUSIONS: We conclude that TMR in ischemic cardiomyopathy (LVEF < or = 30%) has a perioperative risk comparable to that for heart transplantation, but there is no improvement of myocardial performance or life expectancy. Therefore, TMR cannot be regarded as a "bridge," or alternative, to transplantation. However, in individual cases with contraindications for transplantation the anti-anginal effect may justify use of the procedure.

[Long-term follow-up after direct intramyocardial implantation of an internal thoracic artery pedicle (Vineberg operation)]. / Langzeit-Follow-up nach direkter intramyokardialer Implantation eines A. thoracica-interna-Pedikels (Vineberg-Operation).

We report on a patient with coronary artery 3-vessel disease who presented 30 years after a unilateral Vineberg operation with a patent graft. The patient successfully underwent coronary artery bypass grafting. The theoretical basis, operative variations and the results of this historical indirect revascularization procedure are briefly discussed.

Contrast media radiography in patients with retrosternal irrigation drainage for severe sternal wound infection.

Severe wound infection after open-heart surgery is a potentially life-threatening complication, which is mostly treated by re-operation with debridement, and insertion of closed irrigation drainage. Until now there is no consensus about the appropriate duration of irrigation therapy. Since the retrosternal irrigation cavity is likely to become continually smaller as the infection heals, this study was intended to answer the question, as to whether this process can be made visible by the use of contrast media radiography, and whether this information could be used to determine when an irrigation therapy can safely be discontinued. In 1997, 34 patients suffered from sternal wound healing disturbances which required re-operation at our institution (incidence = 0.97%). During the re-operation, a closed retrosternal irrigation drainage was inserted. Of the 34 patients contrast media radiography examinations were carried out on the first, 4th and 12th postoperative day (POD), which consisted of an antero-posterior x-ray of the chest after contrast media injection through each inlet tube. At POD 4 and 12 in the majority of cases, the retrosternal irrigation cavity became smaller when compared with the previous x-ray examination. Only in three of the non-survivors there was a huge irrigation cavity visible at the 12th POD, which sometimes even included the pleural cavity. We conclude that in patients with mediastinitis treated by insertion of a closed irrigation drainage, the retrosternally irrigated cavity seems to become smaller over the therapeutic course of treatment. This process can be visualized by contrast media radiography. Results from this examination should be included in decision making about the best time for discontinuation of the irrigation therapy.

Thoracic transposition of the greater omentum as an adjunct in the treatment of mediastinitis--pros and cons within the context of a randomised study.

Mediastinitis after cardiac surgery is a rare but life-threatening complication. The omentum is particularly well-suited for the treatment of severe sternal wound infections, because it contains large numbers of immunologically active cells that seem to be responsible for the high anti-infective activity of the omentum. The additional transposition of parts of the greater omentum into the thorax was discussed in the development of a protocol for the planned ATMI study, which will investigate the effectiveness of immunoglobulins in the treatment of severe sternal wound infections that require reoperation. We present two different points of view about whether omentopexy should be allowed within the study design.