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Emmeran Gams

Publications and source records attributed to Emmeran Gams.

At least 19 recordsLinked to original sources
PubMed2006

Gene expression in acute Stanford type A dissection: a comparative microarray study.

BACKGROUND: We compared gene expression profiles in acutely dissected aorta with those in normal control aorta. MATERIALS AND METHODS: Ascending aorta specimen from patients with an acute Stanford A-dissection were taken during surgery and compared with those from normal ascending aorta from multiorgan donors using the BD Atlas Human1.2 Array I, BD Atlas Human Cardiovascular Array and the Affymetrix HG-U133A GeneChip. For analysis only genes with strong signals of more than 70 percent of the mean signal of all spots on the array were accepted as being expressed. Quantitative real-time polymerase chain reaction (RT-PCR) was used to confirm regulation of expression of a subset of 24 genes known to be involved in aortic structure and function. RESULTS: According to our definition expression profiling of aorta tissue specimens revealed an expression of 19.1% to 23.5% of the genes listed on the arrays. Of those 15.7% to 28.9% were differently expressed in dissected and control aorta specimens. Several genes that encode for extracellular matrix components such as collagen IV alpha2 and -alpha5, collagen VI alpha3, collagen XIV alpha1, collagen XVIII alpha1 and elastin were down-regulated in aortic dissection, whereas levels of matrix metalloproteinases-11, -14 and -19 were increased. Some genes coding for cell to cell adhesion, cell to matrix signaling (e.g., polycystin1 and -2), cytoskeleton, as well as several myofibrillar genes (e.g., alpha-actinin, tropomyosin, gelsolin) were found to be down-regulated. Not surprisingly, some genes associated with chronic inflammation such as interleukin -2, -6 and -8, were up-regulated in dissection. CONCLUSION: Our results demonstrate the complexity of the dissecting process on a molecular level. Genes coding for the integrity and strength of the aortic wall were down-regulated whereas components of inflammatory response were up-regulated. Altered patterns of gene expression indicate a pre-existing structural failure, which is probably a consequence of insufficient remodeling of the aortic wall resulting in further aortic dissection.

Journal Article↗
PubMed2006

Amiodarone prophylaxis for atrial fibrillation of high-risk patients after coronary bypass grafting: a prospective, double-blinded, placebo-controlled, randomized study.

AIMS: Atrial fibrillation (AF) occurs often in patients after coronary artery bypass grafting (CABG) and can result in increased morbidity and mortality. Previous studies using P-wave signal-averaged electrocardiogram (P-SAECG) have shown that patients with a longer filtered P-wave duration (FPD) have a high risk of AF after CABG. We have shown that patients with an FPD > or = 124 ms and a root-mean-square voltage of the last 20 ms of the P-wave 20 < or = 3.7 microV have an increased risk of AF after surgery. Accordingly, the aim of this study was to investigate whether or not prophylactic peri-operative administration of amiodarone could reduce the incidence of AF in this high-risk group undergoing CABG identified by P-SAECG. METHODS AND RESULTS: In this prospective, double-blinded, placebo-controlled, randomized study, 110 patients received either amiodarone (n = 55) or placebo (n = 55). During CABG, two patients of both groups died. Amiodarone was given as 600 mg oral single dose one day before and from days 2 through 7 after surgery. In addition, amiodarone was also administered intravenously during surgery in a 300-mg bolus for 1 h and as a total maintenance dose of 20 mg/kg weight over 24 h on the first day following surgery. The primary endpoint was the occurrence of AF after CABG. The secondary endpoint was the hospitalization length of stay after CABG. The baseline characteristics were similar in both treatment groups. The incidence of post-operative AF was significantly higher in the placebo group compared with the amiodarone group (85 vs. 34% of patients, P < 0.0001). The prophylactic therapy with amiodarone significantly reduced the intensive care (1.8 +/- 1.7 vs. 2.4 +/- 1.5 days, P = 0.001) and hospitalization length of stay (11.3 +/- 3.4 vs. 13.0 +/- 4.3 days, P = 0.03). In the amiodarone group, concentrations of amiodarone and desethylamiodarone differed significantly between patients with AF and sinus rhythm (amiodarone: 0.96 +/- 0.5 vs. 0.62 +/- 0.4 microg/mL, P = 0.02; desethylamiodarone: 0.65 +/- 0.2 vs. 0.48 +/- 0.1 microg/mL, P = 0.04). CONCLUSION: The incidence of post-operative AF among high-risk patients was significantly reduced by a prophylactic amiodarone treatment resulting in a shorter time of intensive care unit and hospital stay. Our data supports the prophylactic use of amiodarone in peri-operative period in patients at high risk for AF after CABG.

Aged↗
PubMed2006

Forty years of glucose-insulin-potassium (GIK) in cardiac surgery: a review of randomized, controlled trials.

Glucose-insulin-potassium (GIK) solutions have been used in cardiac surgery for more than 40 years. At that time, membrane-polarizing and stabilizing effects on cardiomyocyte's action potential were regarded the main benefit. Two meta-analyses described methodological flaws in the early studies (e.g., case numbers, randomization principles, and levels of significance), and came to clearly different recommendations with regard to the usage of GIK in the therapy of acute myocardial function. During the 70s, as promising therapies for the treatment of AMI had become available (e.g., beta-blockers and thrombolytic agents), the GIK technique was more widely introduced in cardiac surgery, e.g., during valve replacement. At present, 74 of 91 studies provide convincing evidence for the beneficial effects of insulin and/or GIK in cardiac surgery that go far beyond simple metabolic benefits and also include better recovery of myocardial tissue after ischemia. Yet, the exact underlying mechanisms remain still unknown. In this review article, two questions will be answered: why did GIK not become daily routine in cardiac surgery in spite of positive results from clinical studies, and does this technique merit more acceptance among the potential users? In view of the increasing number of older patients at higher risk, the demand for improving surgical procedures has renewed the interest in the GIK concept. The more recent literature suggests that the entire potential of GIK solutions has not been fully disclosed. A large single or multicenter trial with sound endpoints is mandatory.

Adult↗
PubMed2006

Prediction of atrial fibrillation after coronary artery bypass grafting: the role of chemoreflex-sensitivity and P wave signal averaged ECG.

Atrial fibrillation (AF) after coronary artery bypass grafting (CABG) results in a prolonged hospital stay associated with higher costs. In our study P wave triggered P wave signal averaged ECG and chemoreflex-sensitivity (CHRS) was performed on 101 consecutive patients with sinus rhythm before CABG in order to evaluate the utility of these methods to predict AF. A CHRS below 3.0 ms/mm Hg was predefined as a pathological CHRS. Postoperative AF was observed in 37 (37%) of 101 patients. Patients with AF were older (68.4+/-6.9 vs. 63.8+/-9.4 years, p<0.01), had a longer filtered P-wave duration (FPD) (133.6+/-10.2 vs. 123.6+/-14.9 ms, p<0.0001), a lower root mean square voltage of the last 20 ms of the P wave (RMS 20) (2.86+/-0.88 vs. 5.10+/-2.73 microV, p<0.0001) and a significantly lower CHRS (3.32+/-1.83 vs. 4.17+/-2.19 ms/mm Hg, p<0.05). A cut-off point (COP) of FPD> or =124 ms and RMS 20< or =3.7 microV achieved a specificity of 75%, a sensitivity of 78%, a negative predictive value of 86%, a positive predictive value of 64% and an accuracy of 76% for prediction of AF. The predictive power was lower for a pathological CHRS which achieved a specificity of 63%, a sensitivity of 60%, a negative predictive value of 73%, a positive predictive value of 48% and an accuracy of 61%. A stepwise logistic regression analysis of all preoperative variables identified COP (odds ratio 8.21; 95% CI, 2.02-33.37, p<0.003) as independent predictor. Patients with postoperative AF stayed longer in the intensive care unit (2.9+/-1.7 vs. 1.3+/-0.5 days, p<0.0001) and in hospital (13.5+/-4.3 vs. 11.4+/-1.1 days, p<0.0004). The results of our study show that the risk for AF after CABG could preoperatively be predicted with P wave signal averaged ECG and an analysis of CHRS. The predictive power of the COP could be used for a preoperative risk stratification and a corresponding prophylactic therapy in order to reduce costs.

Aged↗
PubMed2006

[Selective I(f) channel inhibition: an alternative for treating coronary artery disease?].

Several clinical studies demonstrate the importance of the heart rate for the cardiovascular morbidity and mortality. Over the last 50 years, some thought has been given to those substances that selectively reduce the heart rate. It is now recognized that I(f) ion channels of the sinus node play a major role in the automatism and modulation of the heart rate. Substances that selectively reduce the heart rate should decrease myocardial oxygen consumption and increase oxygen delivery via the prolonged diastolic coronary perfusion. Direct inotropic effects, however, are unlikely. In principle, anti-anginal and anti-ischemic effects of specific bradycardic substances can be expected. The clinical experience with some of the former bradycardic substances has not been sufficiently convincing. The more recent ivabradine (Procoralan presents an exception to this, as it successfully completed a clinical program for the treatment of chronically stable angina pectoris. In this review article, specific bradycardic substances (= I(f) channel inhibitors) are presented together with the corresponding experimental and clinical studies. The studies were selected against the background of the efficacy of I(f) channel inhibitors in the therapy of cardiovascular disease. As only ivabradine has completed a study on 5,000 patients, the discussion on that particular I(f) channel inhibitor is somewhat extensive. In addition, prospective possibilities and limitations of bradycardic substances are presented.

Anti-Arrhythmia Agents↗
PubMed2006

[Postconditioning: a brief review].

Preconditioning is the most effective form of cardioprotection that can be induced via different interventions before a longer-lasting ischemia (= index ischemia). Preconditioning can be induced by short bouts of ischemia, several pharmaceuticals (e.g., adenosine), and volatile anesthetics. A brief ischemia of an organ other than the heart can likewise initiate protection of the heart, which has been called preconditioning at a distance or remote preconditioning. According to the more recent literature, short bouts of ischemia after an index ischemia can also initiate cardioprotection, e.g., improve postischemic dysfunction or reduce infarct size, which has been called postconditioning. Such a postconditioning can also be elicited at a distant organ, termed remote postconditioning. It is the aim of this short review to characterize preconditioning and in particular postconditioning, describe possible mechanisms, and call attention to the clinical relevance.

Adenosine↗
PubMed2006

In vivo echocardiographic imaging of transplanted human adult stem cells in the myocardium labeled with clinically applicable CliniMACS nanoparticles.

OBJECTIVES: Intramyocardial transplantation of bone marrow-derived cells is currently under clinical evaluation as a therapy of heart failure. A major limitation of all clinical studies dealing with myocardial cell engraftment is the inability to track the fate of the transplanted cells. We present a clinically applicable technique using transesophageal echocardiography (TEE) of CliniMACS nanoparticle labeled transplanted CD133+ cells in ischemic hearts. METHODS AND RESULTS: CD133+ cells were isolated from human bone marrow by CliniMACS magnetic bead selection. Positive (5 x 10(6) cells) cells were transplanted into porcine ischemic myocardium (n = 6). Control animals (n = 5) received medium injection. TEE was performed to demonstrate the distribution of the cells during and 8 weeks after the procedure. Accumulations of labeled CD133+ cells of adjacent injections in the myocardium were discriminatively identified by TEE. CONCLUSIONS: TEE is an elegant method for real-time documentation of successful transplantation and cell colony localization of magnetically labeled CD133+ cells in the ischemic myocardium. Our method should be of special interest for TEE-guided transcatheter injection of cells.

Animals↗
PubMed2006

Delayed preconditioning via Angiotensin-converting enzyme inhibition: pros and cons from an experimental study.

1. Bradykinin B(2) receptor activation confers preconditioning from ischaemic injury. In the present study, we tested whether an angiotensin-converting enzyme (ACE) inhibitor (captopril) could mediate delayed preconditioning and, thus, cardioprotection. 2. New Zealand white rabbits received 15 mL infusion of either saline (control group; n = 7) or drugs (0.3 mg/kg captopril (CAP group; n = 7) or 0.3 mg/kg captopril + 0.1 mg/kg HOE 140 (CAPHOE group; n = 7)) via a marginal ear vein over 30 min. After 24 h, hearts were connected to a Langendorff apparatus and buffer perfused. The experimental protocol consisted of 20 min global normothermic hypoxia, followed by 120 min reperfusion. 3. Compared with baseline, the mean (SEM) contractile state (= dP/dt(max)) at 120 min reperfusion was decreased to 42 +/- ;23, 72 +/- ;16 (*P < 0.05 vs control) and 49 +/- ;22% in the control, CAP and CAPHOE groups, respectively. Early relaxation (= dP/dt(min)) was reduced to 55 +/- ;28, 73 +/- ;15 (*P < 0.05 vs control) and 52 +/- ;19% in the control, CAP and CAPHOE groups, respectively. The estimate for myocardial oxygen consumption (MVO(2)= rate-pressure product) was decreased to 52 +/- ;15, 69 +/- ;24 (*P < 0.05 vs control) and 56 +/- ;15% in the control, CAP and CAPHOE groups, respectively. Similarly, coronary flow was decreased in the control, CAP and CAPHOE groups to 49 +/- ;20, 67 +/- ;18 and 46 +/- ;19%, respectively. In contrast, ventricular extrasystoles during reperfusion were significantly elevated in both the CAP and CAPHOE groups (1.3 +/- ;0.2 and 1.1 +/- ;0.3 /min, respectively) compared with control (0.4 +/- ;0.2 /min). 4. Captopril confers delayed preconditioning against stunning via a B(2) receptor-mediated pathway. This pharmacological preconditioning protects against systolic and diastolic stunning, against vascular stunning and preserves cardiac metabolism. In addition to its accepted cardioprotective effects in early preconditioning, captopril should induce delayed preconditioning (e.g. for routine interventional cardiology or in elective cardiac surgery).

Angiotensin-Converting Enzyme Inhibitors↗
PubMed2006

Abdominal complications following open-heart surgery: a report of 12 cases and review of the literature.

INTRODUCTION: Abdominal complications following open-heart surgery remain serious events as the mortality is reported to be tremendously high. The clinical presentation, the diagnostic strategy and the therapeutic management varies. We reviewed all records of those patients who developed abdominal complications with surgical consequences during the last five years, recorded a complete follow-up and compared the findings to a current view of the literature. PATIENTS AND METHODS: Altogether 5720 patients underwent open-heart surgery at our institution between 1/98 and 12/02. Out of these 12 (10 men, 2 women) developed severe gastrointestinal complications with surgical consequences. The mean age was 73.17 +/- 8.1 I1 years. Seven patients underwent isolated coronary artery bypass grafting (CABG), two patients combined aortic valve replacement (AVR) and CABG, one isolated AVR, one mitral valve replacement (MVR) and yet another one combined MVR and CABG. The clinical records of all these patients were examined and a complete follow-up was recorded. RESULTS: The duration of the entire cardiac operation was a mean of 212.67 +/- 36.97 min, perfusion time 103 +/- 29.32 min and myocardial ischaemic time 52.25 +/- 24.56 min. Length of ICU-stay was between I and 5 days after cardiac surgery. Concerning gastrointestinal complications nine patients suffered from ischaemic intestinal disease, two from gastrointestinal ulcer bleeding and one from a preoperatively unknown bowel tumour with subsequent ileus. Four patients died in the immediate postoperative course, one patient within two years and seven patients show a satisfactory status at follow-up. CONCLUSIONS: A review from the literature shows an enormous mortality from abdominal complications following open-heart surgery. This was also found in our series. As many of these patients have a history of abdominal disease more attention should be paid to such anamnestic hints in the preparation before cardiac surgery. Hence we recommend early diagnostic measures and explorative laparotomy in doubtful situations in patients with positive anamnesis.

Aged↗
PubMed2005

Risk factors of ventricular tachyarrhythmias after coronary artery bypass grafting.

BACKGROUND: Ventricular arrhythmias are rare and represent the most serious arrhythmic complication after coronary artery bypass grafting (CABG). METHODS: The present retrospective study was conducted for identifying patients at risk of ventricular arrhythmias with ventricular signal averaged ECG, standard deviation of all normal RR intervals (SDNN), angiographic and echocardiographic data. We defined ventricular arrhythmias as sustained ventricular fibrillation and ventricular tachycardia. The study population consisted of 209 consecutive patients with sinus rhythm undergoing CABG. The primary endpoint was the occurrence of VA after CABG. The secondary endpoints were hospital length of stay after CABG and the occurrence of VA after hospital discharge. RESULTS: During the postoperative follow-up ventricular arrhythmias were observed in 11 patients (5%). Patients with ventricular arrhythmias showed a higher incidence of ventricular late potentials (91 vs. 9% of patients, p<0.0001) than patients without ventricular arrhythmias. In addition patients with ventricular arrhythmias had a lower left ventricular ejection fraction (44.2+/-15.2 vs. 60.1+/-13.1%, p<0.0001) and a SDNN (22.4+/-8.8 vs. 34.4+/-16.1 ms, p<0.02). A stepwise logistic regression analysis of all variables identified the combination of ventricular late potentials, ejection fraction < or = 38% and SDNN < or = 28 ms (odds rate 26.00; 95% CI, 3.44-196.67, p<0.002) as an independent predictor of ventricular arrhythmias. CONCLUSIONS: The results of our study suggest that the probability of ventricular arrhythmias could be predicted after CABG by a combination of low left ventricular ejection fraction and a measurement of ventricular signal averaged ECG and standard deviation of all normal RR intervals. Patients who can be identified as having a high risk of ventricular arrhythmias should be observed carefully after surgery.

Aged↗
PubMed2005

Evidence for palliative enlargement of the right ventricular outflow tract in severe tetralogy of Fallot.

OBJECTIVE: If the pulmonary artery (PA) tree in patients with Fallot's tetralogy (TOF) is extremely hypoplastic, a shunt procedure may be difficult and not desirable because of side-effects. Moreover, the failing catch-up growth of the pulmonary annulus is well known. In patients with a severe form of TOF, we performed palliative transannular patching of the right ventricular outflow tract. The early and long-term follow-up was evaluated. METHODS: Eleven patients (93 days (10-245 days); 3.5+/-0.7 kg (2.5-4.3 kg)) had highly symptomatic TOF (Hb: 18+/-2g/dl, SO2: 68+/-11%); angiographic diameters: RPA: 4.1 mm (2.5-6.4 mm), LPA: 3.4 mm (1.6-7.0 mm), PA trunc: 4.4 mm (2.5-7.0 mm). All 11 underwent transannular enlargement of the right ventricular outflow tract without closure of the ventricular septum defect. A PA index (cross-sectional area of the pulmonary arteries to BSA) was used to compare pre- and postoperative data. For follow-up, the patients were repetitively examined clinically and echocardiographically. RESULTS: Preoperative PA index was 87+/-40 mm2/m2 (normal: 330+/-35 mm2/m2). Postpalliation angiograms (age: 10-14 months) demonstrated a significant catch-up growth in nine patients (PA index from 99+/-40 to 310+/-54 mm2/m2) and inadequate growth in two patients (PA index 63 and 115 mm2/m2). Perioperative mortality was zero. Ten patients (43 months; 6-105 months) underwent elective repair. Six patients received pulmonary homograft valves (6-15 years after repair) because of severe pulmonary valve insufficiency and severe RV dilation. COMPLICATIONS: One patient died 10 months postpalliation due to pneumonia, one patient received a pacemaker after repair and died (2 months post-repair) due to pacemaker failure, a 5-year-old patient died 1 month after repair due to sepsis. All eight long-term survivors (12-17 years) are in excellent clinical condition. Echocardiography revealed good RV function and near normal diameters at peak systolic pressures between 25 and 50 mmHg. Only one patient developed brady-arrhythmia; a pacemaker was implanted 8 years after repair and 2 years after homograft implantation. CONCLUSIONS: In a very severe form of TOF, palliative right ventricular outflow tract construction may provide the potential for complete repair. In the presented high-risk patient group, mortality was not related to the hypoplastic pulmonary arteries. Obviously, all patients need pulmonary valve implantation in the long run.

Constriction, Pathologic↗
PubMed2005

Is cardiopulmonary bypass a reason for aspirin resistance after coronary artery bypass grafting?

OBJECTIVE: 'Off-pump' coronary artery bypass grafting (OPCAB) is an alternative to conventional coronary artery bypass grafting (CABG) using cardiopulmonary bypass (CPB). While midterm results after OPCAB have become available, systematic studies of changes in platelet function after OPCAB are still missing. Since we have previously shown that oral aspirin treatment (100mg) does not achieve sufficient platelet inhibition in the majority of patients operated on with CPB, we hypothesized that bypass surgery without CPB (off-pump coronary artery bypass, OPCAB) causes less impairment of platelet inhibition by aspirin. The aim of this study was to investigate platelet function and the antiplatelet effect of aspirin after off-pump coronary artery bypass grafting in comparison with conventional on-pump surgery. METHODS: We compared platelet function (in vitro aggregation and thromboxane formation) before and at days 1 and 5 after coronary artery bypass grafting, performed with (n=15) or without (n=14) CPB. Oral aspirin treatment (100mg/d) was started at day 1 after surgery. RESULTS: After a 5 day oral treatment with aspirin, platelet aggregation was inhibited significantly in OPCAB-patients to 55.7+/-16.3% of control before surgery (P<0.05), whereas aggregation remained unchanged after CPB (105.8+/-26.9% of control before surgery; P>0.05). Since aspirin primarily inhibits platelet thromboxane formation, thromoboxane was determined after in vitro aggregation. According to platelet aggregation, thromboxane formation was only inhibited significantly after OPCAB (29.2+/-13.0% of control before surgery, P<0.05), but not after CPB (74.5+/-21.4% of control before surgery, P>0.05). This resistance to aspirin after CPB may be caused by an increased release of new platelets which are competent to form thromboxane, since the number of platelets decreased from 237+/-11x10(3)/microl before CPB to 174+/-13x10(3)/microl at day 1 after surgery and increased significantly the following days reaching 303+/-17x10(3)/microl at day 5. Platelet counts of patients operated on without CPB showed no significant changes (236+/-16x10(3)/microl before OPCAB, 220+/-16x10(3)/microl at day 1 and 266+/-31x10(3)/microl at day 5 after surgery). CONCLUSIONS: The antiplatelet effect of aspirin is largely impaired after CPB, but not after CABG without CPB. Hence, increased platelet turnover after CPB seems to contribute to aspirin resistance, since an increased number of platelets might be competent to form thromboxane within the dosing intervals.

Aged↗
PubMed2005

Stroke as a first manifestation of ovarian cancer.

BACKGROUND: Gynaecologic neoplasms are reported to have the highest potential for developing of ischemic stroke. OBJECTIVES: The history of a female patient, in whom recurrent cerebral embolism was the first clinical sign of occult ovarian neoplasm is described and the casuistic literature to characterise this clinical phenomenon reviewed. RESULTS: Among a large spectrum of neoplasms complicating with ischemic stroke, ovarian carcinoma is one of the most frequently reported in the casuistic literature. The source of systemic microembolisation is endocardits of non-infectious origin; the characteristic diagnostic findings are thrombocytopenia, elevated D-dimers level, and a specific stroke pattern in magnetic resonance imaging. CONCLUSION: Meticulous diagnosis in female, otherwise 'healthy' patients with ischemic stroke, to detect the underlying neoplastic disease is of paramount importance, as early surgical intervention on cancer promises successful therapy for both, cancer and thromboembolism.

Blood Coagulation Disorders↗
PubMed2005

Recurrent embolism in the course of marantic endocarditis.

Marantic or nonbacterial thrombotic endocarditis (NBTE) associated with systemic embolism is usually a complication of advanced or terminal malignancies. We report on the case of a 46-year-old woman in whom nonbacterial thrombotic endocarditis (NBTE)-related cerebral embolism was the first clinical sign of ovarian neoplasm, which was diagnosed after cardiac surgery. Marantic endocarditis should alert the physician to make every effort to diagnose the possible background of this clinical phenomenon. Early identification of NBTE, treatment of the underlying disease, and the associated coagulopathy could possibly prevent cardiac surgery.

Blood Coagulation Disorders↗