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Biomedical subjects

G Nollert

Publications and source records attributed to G Nollert.

At least 37 records · Page 2Linked to original sources
PubMed1998

Effects of a monoclonal antibody to P-selectin on recovery of neonatal lamb hearts after cold cardioplegic ischemia.

BACKGROUND: The interaction between endothelium and leukocytes plays a crucial role in ischemia-reperfusion injury. P-selectin, which is expressed on activated endothelium, mediates the first step in leukocyte adherence to the endothelium. This study examined the effects of a monoclonal antibody (mAb) against P-selectin on the recovery of cardiac function and myocardial neutrophil infiltration after ischemia. METHODS AND RESULTS: Thirteen blood-perfused, isolated neonatal lamb hearts underwent 2 hours of hypothermic cardioplegic arrest and 2 hours of reperfusion. Immediately before reperfusion, mAb to P-selectin was administered to the perfusate (15 micrograms/mL) in 6 hearts (group P-sel). In control (n = 7), the same volume of saline was added. Isovolumic left ventricular function and coronary blood flow were measured. At 2 hours after reperfusion, myocardial myeloperoxidase activity, an index of neutrophil accumulation, was assayed. At 30 minutes of reperfusion, hearts treated with mAb to P-selectin achieved significantly greater recovery of maximum developed pressure (70 +/- 4% in control versus 77 +/- 2% in group P-sel, P < 0.01), maximum positive first derivative of pressure (dP/dt) (64 +/- 7% in control versus 73 +/- 5% in group P-sel, P < 0.05), and maximum negative dP/dt (61 +/- 6% in control versus 70 +/- 6% in group P-sel, P < 0.05) compared with control. Percent baseline of coronary blood flow was also significantly increased in group P-sel (135 +/- 40% in control versus 205 +/- 43% in group P-sel, P < 0.05). Myocardial myeloperoxidase activity was significantly lower (P < 0.05) in group P-sel (4.7 +/- 3.2) versus control (16.0 +/- 10.1). (Units are change in absorbance/min/g tissue.) CONCLUSIONS: The functional blockade of P-selectin resulted in better recovery of cardiac function and attenuated neutrophil accumulation during early reperfusion. Strategies to block P-selectin mediated neutrophil adherence may have clinical application in improving myocardial function at early reperfusion.

Animals↗
PubMed1998

Postischemic hyperthermia exacerbates neurologic injury after deep hypothermic circulatory arrest.

BACKGROUND: Aggressive surface warming is a common practice in the pediatric intensive care unit. However, recent rodent data emphasize the protective effect of mild (2 degrees - 3 degrees C) hypothermia after cerebral ischemia. This study evaluates different temperature regulation strategies after deep hypothermic circulatory arrest with a survival piglet model. METHODS: Fifteen piglets were randomly assigned to 3 groups. All groups underwent 100 minutes of deep hypothermic circulatory arrest at 15 degrees C. Brain temperature was maintained at 34 degrees C for 24 hours after cardiopulmonary bypass in group I, 37 degrees C in group II, and 40 degrees C in group III. Neurobehavioral recovery was evaluated daily for 3 days after extubation by neurologic deficit score (0, normal; 500, brain death) and overall performance category (1, normal; 5, brain death). Histologic examination was assessed for hypoxic-ischemic injury (0, normal; 5, necrosis) in a blinded fashion. RESULTS: All results are expressed as mean +/- standard deviation. Recovery of neurologic deficit score (12.0 +/- 17.8, 47.0 +/- 49.95, 191.0 +/- 179.83; P = .05 for group I vs III), overall performance category (1.0 +/- 0.0, 1.4 +/- 0.6, 2.8 +/- 1.3; P < .05 for group I vs III), and histologic scores (0.0 +/- 0.0, 1.0 +/- 1.2, 2.8 +/- 1.8; P < .05 for group I vs III cortex) were significantly worse in hyperthermic group III. These findings were associated with a significantly lower cytochrome aa3 recovery determined by near-infrared spectroscopy in group III animals (P = .0041 for group I vs III). No animal recovered to baseline electroencephalographic value by 48 hours after deep hypothermic circulatory arrest. Recovery was significantly delayed in the hyperthermic group III animals, with a lower amplitude 14 hours after the operation, which gradually increased with time (P < .05 for group III vs groups I and II). CONCLUSIONS: Mild postischemic hyperthermia significantly exacerbates functional and structural neurologic injury after deep hypothermic circulatory arrest and should therefore be avoided.

Animals↗
PubMed1998

Near-infrared spectrophotometry of the brain in cardiovascular surgery.

Neuropsychological and neurological deficits are still major causes of mortality and morbidity after cardiac operations and are thought to be caused by embolism and cerebral hypoxia. Near-infrared spectrophotometry (NIRS) is a promising method for non-invasive monitoring of cerebral oxygenation and hemodynamics. Different devices provide information on changes of oxygenated (HbO2) and deoxygenated hemoglobin (Hb), oxidized cytochrome aa3 (CytOx) or regional oxygen saturation (rSO2). NIRS has been applied to patients during adult and pediatric cardiovascular surgery with and without deep hypothermic circulatory arrest (DHCA). In most of the studies, significant changes in cerebral oxygenation were detected by NIRS. NIRS measurements were influenced by the cerebral oxygen metabolism and the operative management. However, clinical, experimental, and theoretical issues raise doubts as to the clinical relevance of the hemoglobin saturation (HbO2, Hb, rSO2 signals) during hypothermia and alkalosis, because the oxygen affinity of hemoglobin increases and a high saturation might simply reflect the inadequate oxygen transport into cells. In contrast, recent experiments have proved a high correlation between the CytOx signal and the MRS parameters nucleoside triphosphate and phosphocreatine. Histological damage was significantly related to the lowest CytOx value; in a clinical study it predicted impaired neuropsychological outcome. Therefore, the CytOx signal is of great interest for future studies. NIRS must prove its ability to diagnose cerebral hypoxia consistently during cardiac surgery in a large patient study before this method is brought into routine clinical practice. Absolute quantification and definitions of critical oxygenation margins will be helpful for this goal.

Adult↗
PubMed1997

Long-term survival in patients with repair of tetralogy of Fallot: 36-year follow-up of 490 survivors of the first year after surgical repair.

OBJECTIVES: We sought to analyze risk factors for long-term survival (up to 36 years) after surgical repair of tetralogy of Fallot (TOF). BACKGROUND: Survival after repair is excellent, but data >20 years are rare. METHODS: From 1958 to 1977, 658 patients underwent correction of TOF at our institution and were analyzed for survival. Of this patient group (age 12.2 +/- 8.6 years [mean +/- SD], range 2 to 67), 39.7% had a previous palliation. Operative (n = 139) and 1-year (n = 29) deaths were excluded for long-term calculations, resulting in a study group of 490 patients. RESULTS: Actuarial 10-, 20-, 30- and 36-year survival rates were 97%, 94%, 89% and 85%, respectively. Mortality increased 25 years postoperatively from 0.24%/year to 0.94%/year (p = 0.003). The most common cause of death was sudden death (n = 13), followed by congestive heart failure (n = 6). Multivariate correlates of impaired long-term survival were date of operation (before 1970, p = 0.0104), preoperative polycythemia (p = 0.0487) and use of a right ventricular (RV) outflow patch (p = 0.0079). Postoperative systolic RV/left ventricular pressure ratio and age showed no influence. Patients without preoperative polycythemia and an RV outflow patch (n = 164) had a 36-year actuarial survival rate of 96% and normal life expectancy. CONCLUSIONS: Cyanosis, operative experience of the surgeon and an RV outflow tract patch influence long-term outcome after repair of TOF in older children. Early repair by experienced surgeons to avoid polycythemia and excessive RV hypertrophy is supported by this study. However, mortality risk increases 25 years postoperatively, and thus heart monitoring should be intensified.

Actuarial Analysis↗
PubMed1997

Thirty-year results of Starr-Edwards prostheses in the aortic and mitral position.

BACKGROUND: Between 1963 and 1977 a total of 415 patients admitted to the University Hospital Munich underwent an isolated valve replacement with a Starr-Edwards prosthesis in the aortic or mitral position. METHODS: A retrospective follow-up of 87.1% of the patients representing 4,254 patient-years was completed. Surviving patients were examined by means of echocardiography. RESULTS: Survival rates after 10, 20, and 30 years were 62.3%, 39.4%, and 19.9% after aortic valve replacement and 75%, 36.5%, and 22.6% after mitral valve replacement (operative mortality excluded). Freedom from all valve-related complications, reoperations, and valve-related death was 66.4%, 43.3%, and 23.8% after aortic valve replacement and 73.4%, 35.4%, and 14.3% after mitral valve replacement. Of the surviving patients, 82% and 76% who received aortic or mitral valves, respectively, are in New York Heart Association class I or II. The pressure gradients of the aortic valves were between 20 and 73 mm Hg; those of the mitral valves were between 9 and 30 mm Hg. Fifty-two percent of aortic and 68% of mitral valves show no echocardiographic peculiarities. The left ventricular function in both groups is normal in 64%. CONCLUSIONS: The long-term results together with the echocardiographic results show that after 30 years the Starr-Edwards valve represents a standard that still needs to be achieved by newer prostheses.

Adult↗
PubMed1997

Long-term results of total repair of tetralogy of Fallot in adulthood: 35 years follow-up in 104 patients corrected at the age of 18 or older.

Long-term survival after surgical repair of tetralogy of Fallot (TOF) is reported to be excellent if the patients are corrected in childhood. However, age at operation has been demonstrated as an important risk-factor. The aim of our study was to investigate whether adult patients also benefit from surgery. From December 1958 to May 1977, 739 patients underwent a correction of their TOF with pulmonary stenosis at our institution. Foreigners (n = 52) and those who moved to a foreign country (n = 13) were excluded from further analysis. Sixteen patients were lost during follow-up (98% complete). Of the remaining patient population (n = 658; mean age: 12.2 +/- 8.6 years; range 2-67 years), 104 patients were 18 years or older at the time of correction. Operative (n = 25) and one-year (n = 8) deaths were excluded for long-term calculations, resulting in a study group of 71 patients. Actuarial 10, 20, 30, and 35-year survival rates were 94%, 93%, 83%, and 72% respectively, and not different from normal life expectancy. The most common cause of death was congestive heart failure (n = 3), followed by myocardial infarction (n = 2) and sudden death (n = 2). Parameters influencing longterm survival could not be detected. At follow-up (mean 27.7 years), more than 80% (n = 48) of the 58 survivors reported themselves to be in NYHA functional class I or II and 95% (n = 55) were in a better condition than before the operation. Repair of tetralogy of Fallot in adulthood shows excellent results with normal life expectancy for the patients.

Adult↗
PubMed1997

Transgenic human decay accelerating factor makes normal pigs function as a concordant species.

BACKGROUND: Increasing interest has focused on xenotransplantation as a potential solution to the organ shortage. To overcome hyperacute rejection, pigs have been produced that are transgenic for human decay accelerating factor (DAF). For the evaluation of the effects of human DAF, an ex vivo working heart model was used. METHODS: We compared hemodynamic performance of four transgenic pig hearts (group A) with that of four Landrace pig hearts (group B) and eight rhesus monkey hearts (group C). For perfusion fresh blood had been taken from healthy volunteers. From the coronary sinus effluent, samples were taken for the determination of 6-keto prostaglandin F1 alpha, prostaglandin E2, creatine phosphokinase, and lactate dehydrogenase, respectively. Hemodynamic parameters were measured continuously for 150 minutes after the start. After 15 minutes of reperfusion, the Langendorff-mode was switched to the working heart model. After hearts failed to pump against the afterload column, experiments were terminated, and tissue sections were taken for electron microscopy. RESULTS: Groups A and C showed superior cardiac performance as measured by stroke work index (SWI) that exceeded group B by 2.5 to 3 times (p < 0.05). In all three groups the SWI slowly decreased during perfusion. In group B, SWI decreased to a minimum as early as 90 minutes after the start. In all groups, 6-keto prostaglandin F1 alpha and prostaglandin E2 as indicators of endothelial cell activation increased. In group B, however, the levels exceeded those of groups A and C by six and nine times, respectively (p < 0.05). As markers of myocardial damage, creatine phosphokinase and lactate dehydrogenase increased in all groups. But again levels in group B exceeded those of groups A and C by four to five times (p < 0.05). Electron microscopy revealed single cell necrosis in group B, whereas groups A and C showed interstitial edema only. CONCLUSIONS: Our experiments indicate a crucial role of DAF in preventing rejection in discordant species combinations. Transgenic human DAF seems to inhibit successfully complement-mediated damage to the endothelial cell, thus preventing endothelial activation and consequently myocardial damage. Transgenic human DAF makes a discordant species (pig) function as a concordant species, that is, hyperacute rejection does not occur.

6-Ketoprostaglandin F1 alpha↗
PubMed1997

Surgical therapy for coronary artery disease in patients with a left ventricular ejection fraction of 25% or less.

BACKGROUND: In patients with advanced coronary artery disease (CAD) and markedly decreased left ventricular ejection fraction (EF) symptoms of myocardial ischemia and insufficiency may be complicated by ventricular arrhythmias. Appropriate surgical therapy must be tailored to the individual symptoms. The aim of this study was to compare the different current methods. METHODS: From 9/1990 to 9/1994 138 patients with coronary artery disease and a left ventricular EF of < or = 25% were operated. Patients with dominating Angina pectoris and vital myocardium were revascularized (ACB; n = 17); two of these patients were 12 and 37 months p.o. transplanted. Because of dominating dyspnea, diffuse CAD and missing AP heart transplantation seemed indicated (HTX; n = 102). In two of these patients ventricular assist devices were implanted as a bridge to transplantation; both patients survived. Patients with malign tachycardias received either an implantable cardio-defibrillator (ICD; n = 16) or had arrhythmia surgery (ARS; n = 3). Patients of the HTX-Group were younger (54 vs 60 years; p < 0.05), had more often previous surgery (28% vs 20%) and were in worse conditions (NYHA 3.5 vs 3.0; p < 0.05). RESULTS: The main cause of death after transplantation was multi-organ failure (MOF; 14/102; 13.8%). The best long-term survival (87% after 3.2 years, p < 0.01 vs HTX)-with low average functional classes (NYHA 2.9)-had the patients after ICD implantation. The best quality of live (NYHA 1.1; p < 0.01 vs ICD)-associated with a high mortality due to preoperatively impaired organ-systems (62% operative survival, 57% 4-years survival)-was achieved by transplantation. In patients with a history of ventricular arrhythmias, who are waiting for a transplantation, the implantation of an ICD should be considered. Bypass surgery as well as arrhythmia surgery showed good survival (1-year survival 82% and 66% respectively) and functional results (NYHA 1.7 and 1.5 respectively).

Arrhythmias, Cardiac↗
PubMed1997

Tacrolimus: a superior agent to OKT3 for treating cases of persistent rejection after intrathoracic transplantation.

Acute myocardial rejection refractory to treatment still contributes significantly to patient death after intrathoracic transplantation. A historical series of 25 patients who received OKT3 (5 mg/day for 10 days) was compared with our current experience with 14 patients treated with tacrolimus (0.1 mg/kg/day targeting whole blood concentrations of 13 to 18 ng/ml): all 39 patients having persistent rejection unresponsive to treatment at the time of conversion. Mean periods of follow-up were 842.9 days and 342.6 days, respectively. Actuarial 1-year patient survival rates were 64.0% and 76.2% for the OKT3 and tacrolimus treatment groups, with most of the deaths in the OKT3 group occurring early (p = 0.064). Causes of death for patients receiving OKT3 included acute rejection (n = 5), infection (n = 3), carcinoma (n = 2), multiorgan failure (n = 1) and graft vessel disease (n = 1). The two deaths in the tacrolimus treatment group were the result of infections. Eighty percent of patients treated with OKT3 subsequently experienced further rejection episodes, in many cases necessitating methotrexate therapy. In contrast, only one patient (7.1%) from the tacrolimus group was diagnosed with rejection after conversion (p < 0.001). In conclusion, when compared with OKT3 therapy, a switch in baseline immunosuppression from cyclosporine to tacrolimus seems to be markedly more effective, as well as being safe for the treatment of persistent acute rejection.

Actuarial Analysis↗
PubMed1996

Prevention of hyperacute rejection by human decay accelerating factor in xenogeneic perfused working hearts.

As a potential source of organs for xenotransplantation, pigs that are transgenic for human decay accelerating factor (DAF) have been bred in order to overcome hyperacute rejection. We investigated the protective effect of human DAF in a porcine working heart model perfused by human blood. Hearts of normal landrace pits served as controls. The following parameters were measured: stroke work index, coronary flow and arteriovenous oxygen consumption, 6-keto prostaglandin F1alpha and prostaglandin E2 as markers of endothelial cell activation; creatine phosphokinase and lactate dehydrogenase for evaluation of the extent of myocardial damage; TNFalpha and IL-6 as markers of mononuclear cell activation. Histological and ultrastructural investigations from myocardial tissue sections were done at the end of perfusion. Human (h) DAF appeared to inhibit complement-mediated endothelial cell activation of transgenic pig hearts successfully. This was in contrast to landrace pig hearts, which had a sixfold increase of prostaglandin levels during perfusion with human blood. The cardiac weight increase during perfusion time due to interstitial edema tended to be less in the hDAF group. Myocardial damage was minimal in transgenic hearts, whereas normal pig hearts produced a threefold increase of creatine phosphokinase and lactate dehydrogenase levels. In these hearts, electron microscopy revealed single cell necrosis of myocytes and vacuolization of mitochondria with cristae rupture. According to the results obtained in the working heart model, the breeding of pigs that are transgenic for hDAF represents a promising step to making heart xenotransplantation a clinical reality in the future.

Acute Disease↗
PubMed1996

[Quality assurance in heart surgery. General and personal concepts].

In the era of managed health care quality assurance has become more and more important. In cardiac surgery immense costs have to be justified. Some of the patients might be treated alternatively with drugs or by cardiological interventions. Additionally, the operative risk is still not neglectable in cases with substantial comorbidities and advanced age. Therefore in Germany, a nationwide quality assurance system was established in 1992 covering more than 90% of the cases in more than 90% of the centers. The goals of quality assurance have to address the needs of the patients, insurance companies, and surgeons, and thereby define the primary endpoints for analysis: mortality, quality of life, and therapy costs including reinterventions. A precondition for a sufficient quality assurance system is the isolation of quality relevant data by multivariate analysis and its documentation. Weighing the different factors allows a risk stratification in order to compare the results of various centers with different patient populations. For every center an expected mortality is calculated, and compared with the observed mortality. By taking the average mortality into account a risk adjusted mortality is derived for every center, which is independent from the patient population. An automated continuous follow-up of the patients is essential and allows assessment of 30-day mortality, reinterventions and quality of life. In 1986, the German Society of Cardio-thoracic-surgery initiated the development of a multicentric method of quality assurance (Quadra). In 1992 the insurance companies agreed to cover the costs for the reduced documentation of 205 parameters for every patient undergoing CABG, valve surgery or repair of an aneurysm with the help of cardio-pulmonary bypass; a 30-day follow up is included. Isolation of risk factors has not been performed because the quality of the data was not considered valid due to incomplete documentation and non-rigorous data control. For the first time in 1990, New York State Department of Health published data on risk adjusted mortality in CABG separate for every hospital. Due to a lawsuit brought on by the journal "Newsday" the department was forced to publish the results of every surgeon. Each clinic reports 41 different patient parameters, which are controlled for completeness and accuracy by an independent committee. The efficacy of this system has been proved by a 41% reduction in mortality from 1989 to 1992 mainly due to changes in patient management. Raw mortality rates to different hospitals in CABG were published by the administration of the insurance companies in 1986 leading to misinterpretations by the public. In response, the Society of Thoracic Surgeons initiated a database to calculate risk adjusted data. Today, more than 50% of all US-American centers participate and more than 700,000 patients have been reported. The data is not controlled and the majority of participating hospitals are small community centers. We have developed a methodology of quality assurance which estimates the operative risks of an individual patient by calculating the survival curve of all patients with the same risk profile who have already been operated on in our center. An automated long-term follow-up at one and five years after surgery provides the data for the calculation. The development of an effective quality assurance in the US was forced by media and insurance companies. Presentation of incorrect or misleading data in Germany has already damaged the image of cardiac surgery and surgeons. Therefore, there are no alternatives to public presentation of risk-adjusted mortalities in order to regain trust. Fears of surgeons and hospitals with results below the average are serious and patients with a high mortality risk may be afraid of not being operated on, although the New York System shows that these fears have not become real...

Cardiac Surgical Procedures↗
PubMed1995

Determinants of cerebral oxygenation during cardiac surgery.

BACKGROUND: Neuropsychological deficits after cardiac surgery are attributed to the side effects of cardiopulmonary bypass (CPB). To protect the brain from ischemic damage, the influences of temperature, blood pressure, blood gases, acid-base status, and hemodilution on cerebral oxygenation have to be elucidated and quantified. METHODS: Forty-one consecutive patients were investigated during cardiac surgery while on CPB. Operative management included moderate hypothermia of 26 degrees C and the alpha-stat pH management. With near-infrared spectrophotometry, changes in oxygenated hemoglobin (HbO2, representing oxygen delivery) and oxidized cytochrome a,a3 (CtO2, cellular oxygenation) in brain tissue were obtained noninvasively. In addition, venous saturation of the brain was measured via a catheter in the jugular bulb (SBJO2). The influence of operative management parameters on cerebral oxygenation was calculated by univariate and multiple regression analyses. RESULTS: Before and after CPB there was no significant multivariate determinant of cerebral oxygenation. During CPB, HbO2 depended solely on PCO2 (P < .01; r = .89). CtO2 was determined by pH (P < .01), esophageal temperature (P < .01), PCO2 (P < .01), and Hb (P < .01). These parameters explained nearly all changes of the cytochrome measurements during CPB (r = .99). Arterial PCO2 (P < .01) and pH (P < .01) influenced brain venous oxygen saturation (SBJO2; r = .98). CONCLUSIONS: Cerebral oxygenation is autoregulated during cardiac surgery before and after CPB. During CPB, Hb, temperature, pH, and PCO2 determined at least 85% of all changes in cerebral oxygenation. The main causes of impaired cerebral oxygenation are the decrease in Hb with hemodilution, vasoconstriction due to hypocapnia, and the leftward shift of the Hb binding curve in alkalosis and hypothermia.

Adult↗
PubMed1995

Postoperative neuropsychological dysfunction and cerebral oxygenation during cardiac surgery.

In 41 patients undergoing cardiac operations with extracorporeal circulation, oxidized cytochrome a,a3(CtO2), deoxygenated hemoglobin (Hb), and oxygenated hemoglobin (HbO2) were measured in brain tissue by near-infrared spectrophotometry (NIRS) intraoperatively. Monitoring also included electroencephalography (EEG) and jugular-bulb venous saturation (SBJO2). All operations were performed using membrane oxygenators, moderate hypothermia (26-28 degrees C) and pH alpha-stat management. During cardiopulmonary bypass (CPB) CtO2 and HbO2) were reduced, reaching minimal values when rewarming was instituted. At the end of the operation CtO2 and HbO2 had regained initial levels. During CPB, arterial PCO2, pH, and temperature were closely related to CtO2 (r = 1000, r = -0.964 and 0.929 respectively; p < 0.001, p < 0.001, and p < 0.003 respectively). Neuropsychological testing by the Mini-Mental-State Test indicated reversible postoperative neuropsychological deficits in four patients. There patients had a lower CtO2 minimum compared to those without these deficits (-4.5 mumol/L v. -0.7 mumol/L; p = 0.036). These findings support the hypothesis that neuropsychological deficits in patients after cardiac surgery can be caused by intraoperative cerebral hypoxia.

Adult↗
PubMed1995

Comparison of porcine biological valves with pericardial valves--a 12-year clinical experience with 1123 bio-prostheses.

In order to evaluate selective differences of biological porcine valves versus pericardial valves and to analyze various valve models, 8 different bioprostheses (4 porcine valves, 4 pericardial valves) were studied in a 12-year follow-up. From 1978 to 1990, 476 porcine bioprostheses (Carpentier-Edwards: n = 104, Carpentier Edwards Supraanular: n = 59, Hancock I: n = 41, Hancock II: n = 272) and 647 pericardial valves (Hancock-Extracorporeal: n = 479, Ionescu-Shiley: n = 76, Carpentier-Edwards: n = 57, Mitroflow: n = 35) were implanted. At time of implantation, the patient age ranged from 21-85 years, mean 57.1 +/- 12.4 years. 831 patients were analyzed in the long-term follow-up (62.3 +/- 18.6 months, cumulative follow-up of 6632 patient-years). The incidences of thromboembolic complications (TE), endocarditis (E), primary tissue failure (PTF), rate of reoperation (ReOp), and late mortality due to prosthesis dysfunction were analyzed, calculated, and compared within the different valve models (actuarial data, chi 2 test, log rank analysis). The incidences of TE and E were lower for pericardial valves when compared with porcine bioprostheses (TE: 0.88 vs. 1.8%/patient year; E: 0.24 vs. 0.5%/patient year); within the 2 groups, the different valve models did not show any major differences. However, the incidence of PTF was significantly higher in the pericardial valve group, being 36 +/- 6.5%, 68 +/- 10% and 86 +/- 19.5% after 6, 8, and 10 years; the respective figures for the porcine valves were 6 +/- 3.5%, 18 +/- 7.1%, and 60 +/- 13.1% (p < 0.001).(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1995

Coronary artery bypass grafting after failed coronary angioplasty: risk factors and long-term results.

In this case-control study we investigated the preoperative risk factors and long-term results in patients undergoing emergency coronary artery bypass grafting (CABG) after failed percutaneous transluminal coronary angioplasty (PTCA). From January 1990 to March 1993, 56 emergency CABGs (Group A) were performed in patients from 7 different cardiology centres--six of these located outside our hospital within a radius of 19 km-1 h to 114 h (phi 7.3 h) after failed PTCA. No special stand-by was given and patients were operated in the next available theatre. Criteria of anatomically unfavourable stenoses for PTCA were defined as follows: Long stenoses, occlusions of other major vessels, tandem stenoses, stenoses at or near a bend or branch and, finally, eccentric stenoses. Thirty-two percent met one criterion, 35.8% two, 6.9% three and 1.8% four criteria. All patients were examined echocardiographically 14.6 +/- 8.2 months postoperatively. Patients who had been operated on electively within the same period served as a control (Group B; n = 56; case-control study). The patients were matched for age, sex, EF, LVEDP, body surface area, reoperation status, and concomitant diseases. The mortality rate for Group A patients was 10.7% (n = 6); for Group B, 1.8% (n = 1). Five of the Group A patients who died came from our own hospital and only one from a hospital 1 km away (mortality: 14.3% vs. 4.8%). There were no deaths among patients with an anatomically favourable stenosis for a PTCA; in patients with more than one criterion for an unfavourable stenosis mortality increased to 19.0% (p < 0.05).(ABSTRACT TRUNCATED AT 250 WORDS)

Age Factors↗