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S Kerber

Publications and source records attributed to S Kerber.

At least 55 records · Page 3Linked to original sources
PubMed1997

A prognostic computer model to predict individual outcome in interventional cardiology. The INTERVENT Project.

It is not yet possible to predict an individual's outcome from percutaneous transluminal coronary angioplasty or alternative/adjunctive coronary interventional techniques. The purpose of the INTERVENT project is to redefine complications associated with coronary interventions, to set up a prognostic computer model to predict individual outcome and to compare the results to those of conventional statistical techniques. 2500 data items were analysed in 455 consecutive patients (mean age: 61.1 +/- 8.3 years; range 33-84 years; 80.4% male, 16.7% unstable angina, 5.1%/10.1% acute/subacute myocardial infarction) undergoing coronary interventions at three university centres. In-lab/out-of-lab complication rates were 0.4%/0.9% (death), 1.8%/0.2% (abrupt vessel closure with myocardial infarction) and 5.5%/4.0% (haemodynamic complications). Computer algorithms derived by applying techniques from artificial intelligence were able (1) to reduce the set of possible relevant risk factors from 2500 to about 40, (2) to predict individual risk with an accuracy of > 95% and (3) to explain the structural relationship between outcome and risk factors. Patient data from two centres were used to construct and test the algorithm. Data from a third centre were used to evaluate the algorithm. The most important predictors-were acute myocardial infarction, heart failure (NYHA class > II), unstable angina, complex lesions, high low density lipoprotein cholesterol and duration of coronary heart disease. Neither age nor gender impaired the percutaneous transluminal coronary angioplasty results in acute ischaemic syndromes; however, for stable angina, procedural risk increased with age. There was little risk from primary percutaneous transluminal coronary angioplasty in acute myocardial infarction in patients with NYHA heart failure classes I-II; however, the risk was high for patients in NYHA classes > II, either with or without additional thrombolysis. Alternative/adjunctive intervention techniques were no predictors for in-lab-, but were predictors for post-procedural complications.

Adult↗
PubMed1997

Progressive heterogeneity of myocardial perfusion in heart transplant recipients detected by thallium-201 myocardial SPECT.

UNLABELLED: Progressive graft atherosclerosis is a serious complication in long-term survivors after heart transplantation. Coronary angiography is insensitive with regard to the early and characteristic alterations. We evaluated the progression of these abnormalities and the influence of former rejection episodes. METHODS: Early after transplantation, 43 patients (34 men, mean age 53.7 +/- 10.7 yr) underwent stress and redistribution 201Tl myocardial SPECT after treadmill exercise. Twenty patients were followed-up to the second postoperative year, and 13 patients to the third postoperative year. Thallium-201 distribution and kinetic abnormalities were documented in a scheme enclosing 20 myocardial segments. Additionally, a score was developed that measured the degree of inhomogeneity of 201Tl distribution and the severity of perfusion defects, respectively. RESULTS: Regarding scintigraphy, pathologic results could be found in 40% of segments (redistribution, 25%; reverse redistribution, 30%; persistent defects, 49%). Score values in heart transplant recipients differed significantly from normal controls (p < 0.001) and were comparable to patients with single vessel disease of their native hearts. Thallium-201 inhomogeneity in recipients after treatable rejection episodes did not differ from results in recipients without any biopsy-proven rejection. The follow-up of cardiac transplant patients revealed a significant increase of score values up to the third year after transplantation (p < 0.02), despite reproducible normal angiography. There was no direct correlation between score values and IVUS results, although there was a parallel trend in 10 of 12 follow-ups. CONCLUSION: Despite normal coronary angiography, 201Tl myocardial SPECT frequently revealed pathologic results in heart transplant recipients. Scintigraphic results did not correlate with intimal thickening of epicardial coronary arteries accessible to intravascular ultrasonography in the early phase after transplantation. The presented score of inhomogeneity might reveal progressive disease possibly caused by small vessel alterations.

Case-Control Studies↗
PubMed1997

Long-term left ventricular assist device support: a novel pump rate challenge exercise protocol to monitor native left ventricular function.

A novel, hemodynamically guided exercise protocol with two different left ventricular assist device settings in two long-term recipients is presented. This protocol allows for quantitation of the contribution of the native left ventricle to total cardiac output. It facilitates estimation of the risk associated with device dysfunction, as well as prediction of left ventricular recovery and the potential for weaning.

Adult↗
PubMed1996

Can Tl-201 myocardial SPECT abnormalities in orthotopic heart recipients be explained by coronary vessel wall alterations assessed by intravascular ultrasound?

UNLABELLED: The aim of this study was to compare findings on coronary intravascular ultrasound and thallium-201 SPECT in patients following orthotopic heart transplantation. BACKGROUND: No data are available on whether pathological thallium scintigraphic findings in heart recipients are based on coronary vessel wall alterations identifiable by intravascular ultrasound. METHODS: 29 patients (mean age: 50.9 +/- 11.5 years; male n = 23) were investigated by means of intravascular ultrasound of selected coronary segments and thallium-201 myocardial SPECT. Patients were investigated 11.6 +/- 5.4 weeks post transplantation, a subgroup of 13 patients was re-investigated 70.2 +/- 18.4 weeks following transplantation. A total of 214 cross-sectional areas of the left coronary artery were examined using a 3.5 French intravascular ultrasound catheter to measure intimal index and the circumferential extension of a three-layer appearance of the vessel wall. Shortly after catheterisation, an ergometric stress-test was performed to examine all recipients by means of thallium-201 SPECT. In each patient, 20 segments of the left ventricle were evaluated using a score system of differentiate between persistent defects, redistribution, and reverse redistribution. A score was developed that measured the degree of inhomogeneity and severity of perfusion defects, respectively. Findings on scintigraphy were correlated to coronary intravascular ultrasound findings. RESULTS: At first investigation, mean intimal index of all evaluated coronary cross-sectional areas was 0.06 +/- 0.1. Sixty-four cross-sectional areas demonstrated a three-layer appearance of the vessel wall, mean circumferential extension was 72 +/- 122 degrees. Thallium scintigraphy demonstrated a total of 336 (40%) pathological left ventricular segments; 168 (20%) were regarded as permanent defects, 67 (8%) demonstrated redistribution and 101 (12%) showed reverse redistribution. The score of inhomogeneity was calculated as 5.8% +/- 2.6%. In the subgroup of patients at the follow-up study, the score was 6.4 +/- 2.8%. There was no correlation between intimal index and the score, nor could any correlation be confirmed between the score and the circumferential extension of a three-layer appearance of the vessel wall. At second investigation, no significant differences of intimal index (0.05 +/- 0.07) or circumferential extension of a three-layer appearance of the vessel wall (74 +/- 118 degrees) could be confirmed. The score was slightly, but significantly increased to 8.1 +/- 4.5% at the second investigation (P < 0.05). CONCLUSION: Early after orthotopic heart transplantation, pathologic thallium distribution patterns of the left ventricle could be observed. These pathological patterns did not correlate with the extent of diffuse coronary vessel wall alterations identifiable by intravascular ultrasound. After more than 1 year, the degree of scintigraphic abnormalities increased significantly, not accompanied by an increase of diffuse coronary vessel wall alterations.

Adult↗
PubMed1996

Isochromosome Xq in Klinefelter syndrome: report of 7 new cases.

In this collaborative study we report on 2 prenatally and 5 postnatally diagnosed cases with a 47,X,i(Xq),Y chromosomal constitution. Excepting tall stature, the 5 adult patients showed all typical manifestations of Klinefelter syndrome. Taken together with previously reported cases, these data suggest that Klinefelter syndrome with isochromosome Xq has a favorable prognosis with normal mental development, and with normal-to-short stature. The prevalence of this Klinefelter variant is calculated to be between 0.3-0.9% in males with X chromosome polysomies.

Adult↗
PubMed1996

Heart transplant candidates at high risk can be identified at the time of initial evaluation.

The increasing discrepancy between the numbers of patients selected for cardiac transplantation and the available donor organs requires validation of markers of high risk at the time of initial evaluation that may help to determine which patients profit from aggressive therapy. We retrospectively examined the case records of 91 heart transplant candidates selected out of a total of 140 consecutive patients referred for evaluation. Of these 91 patients, 48 were transplanted during follow-up. Of the remaining 43 patients, 25 died after a mean survival time of 1.6 +/- 2.5 months. The causes of death were pump failure in 18 (72%) and sudden cardiac death in 7 (28%). Multivariate analysis identified 4 out of 26 parameters at initial evaluation that distinguished the 25 nonsurvivors from the 18 survivors. These were: mean arterial pressure (P = 0.03), pulmonary capillary wedge pressure (P = 0.002), mean pulmonary artery pressure (P = 0.001), and fractional shortening (P = 0.007). The mode of death could not be predicted. We conclude that there are prognostic markers at initial evaluation that allow more restrictive selection of patients for cardiac transplantation and mechanical bridging.

Adult↗
PubMed1996

The use of a Perma-Flow graft for coronary artery bypass surgery.

We report on our first clinical use of a Perma-Flow graft for coronary artery bypass surgery (CABG). It may well be that repeated successful use of this graft will offer a chance for revascularization to patients who might otherwise have been denied for lack of appropriate vessels.

Aged↗
PubMed1996

Beating heart implantation of a wearable NOVACOR left-ventricular assist device.

Implantable left-ventricular assist devices (LVAD) are successfully used as a bridge to transplant if the patient's condition is worsening and no donor organ is available. They allow recovery of compromised organ function. However, postoperative bleeding, thrombemboelism, and right-heart failure may jeopardize the important improvement of organ function and may even lead to death. We introduce our strategy for implantation of the Novacor LVAD system, which aims at minimal bleeding and maintained right-heart function. The Novacor LVAD was implanted with the heart beating during extracorporeal circulation in 8 patients, 3 of whom had previous cardiac surgery. Postoperatively, no patient developed right heart failure or had to undergo redo thoracotomy.

Adult↗
PubMed1996

Multiple cardiac procedures after heart transplantation: a case report.

We report on a 56-year-old patient who underwent coronary artery bypass grafting, tricuspid valve replacement, and pacemaker implantation within 49 months after heart transplantation. This case readily demonstrates that multiple cardiac procedures can be safely performed after heart transplantation and may thus serve as an alternative to retransplantation.

Cardiac Surgical Procedures↗
PubMed1996

Coronary compliance in patients following orthotopic heart transplantation. An intravascular ultrasound study.

BACKGROUND: The aim of this study was to investigate coronary compliance in patients early and 71.8 weeks after orthotopic heart transplantation. METHODS: Thirty patients (mean age 51.4 years, women n = 6) underwent coronary angiography early after orthotopic heart transplantation (mean interval 11.6 +/- 5.5 weeks), by which time 12 recipients had already been treated for episodes of rejection. A total of 153 different coronary segments were investigated using a mechanical 30 MHz intravascular ultrasound system. In all segments, the intimal index and the circumferential extension of the vessel wall, which had a three-layered appearance, were assessed. Systolic-diastolic changes in area, and pressure with respect to vessel wall area, were used to study normalized compliance. All measurements were repeated in a subgroup of 13 patients 71.8 +/- 10.7 weeks after transplantation. RESULTS: At the first investigation, the mean intimal index of all estimated cross-sectional areas was 0.07 +/- 0.10. The mean circumferential extension of the 'three-layered' coronary vessel wall was 74 degrees +/- 101 degrees. No correlation could be found between normalized compliance and the intimal index (r = -0.322, P < 0.001) or between normalized compliance and the circumferential extension of the three-layered vessel wall (r = -0.362, P < 0.001). Donor age did not correlate with normalized compliance either (r = -0.515, P = 0.004). In 12 patients with proven rejection periods before the first investigation, normalized compliance was significantly lower (1.76 +/- 0.81 mmHg-1) than in those without rejection (2.95 +/- 1.22 mmHg-1, P = 0.005). Both the intimal index and the circumferential extension of the three-layered architecture of the vessel wall were significantly higher in recipients with rejection periods. A comparison of the subgroup of 13 recipients between first and second investigation showed that the intimal index increased slightly from 0.03 +/- 0.03 to 0.09 +/- 0.13 (ns) 71.8 weeks after transplantation, but that normalized compliance did not differ significantly between the first and the follow-up investigation. CONCLUSIONS: Early after orthotopic heart transplantation, normalized compliance does not correlate with donor age or the extent of atherosclerotic vessel alterations identifiable by intravascular ultrasound. Early rejection periods are associated with reduced coronary arterial compliance. Using intravascular ultrasound, this adverse functional effect on arterial compliance can be observed together with an increase in the intimal index.

Adult↗
PubMed1996

[Conventional nuclear medical diagnosis in the after care of heart transplantation].

Actually more than 80% of heart recipients survive the first postoperative year. Early death is mainly caused by rejection and acute infection. After the first year progressive graft atherosclerosis has the greatest impact on prognosis. The review presents scintigraphic methods that have reached clinical impact in the diagnosis of rejection and vascular complications. Immunoscintigraphy with 111In-labelled monoclonal antibodies against myosin proved to be of importance in the diagnosis of rejection especially in long-term follow-up. Perfusion scintigraphy reveals vital and ischemic myocardium. In heart transplant recipients radionuclide ventriculography has been widely replaced by echocardiography. Up to now, the evaluation of increasing nerval integration with 123I-MIBG has not reached clinical impact.

Actuarial Analysis↗
PubMed1996

[Intravascular sonographic findings after orthotopic heart transplantation: comparison with clinical factors].

30 patients (mean age 51.4 +/- 11.6 years; female n = 6) were studied early after orthotopic heart transplantation (11.6 +/- 5.5 weeks). Twelve recipients had undergone specific treatment for biopsy proven rejection. Using a mechanical intravascular ultrasound device (3.5-F catheter), 153 coronary artery segments (16 left coronary main stem, 122 left anterior descending artery, 15 left circumflex artery) were studied. Intimal index and circumferential extension of a three-layer appearance of the vessel wall were assessed. In all segments, systolic-diastolic changes in area (delta A) with respect to vessel area and pressure (delta P) were used to study normalized compliance (normalized compliance = [delta A/A]/delta P [mm Hg-1 x 10(3)]). Intravascular ultrasound findings were correlated to perioperative ischemia time, LDL/HDL-ratio, Lp(a) and donor age. In a subgroup of 13 recipients, intravascular ultrasound investigation was repeated after an interval of 67.4 +/- 10.2 weeks. At first investigation, mean intimal index of all coronary segments was 0.07 +/- 0.10. Mean circumferential extension of a three-layer appearance of the vessel wall was 84 +/- 112 degrees. Normalized compliance was 2.43 +/- 1.90 mm Hg-1 in the left main stem 2.45 +/- 1.47 mm Hg-1 within the left anterior descending artery, and 2.66 +/- 1.72 mm Hg-1 within the circumflex artery (differences n.s.). No correlation was found between intimal index and normalized compliance (r = -0.322), nor between circumferential extension of intimal thickening and normalized compliance (r = -0.362). Furthermore, there was no correlation between normalized compliance and donor age. Normalized compliance was significantly lower in recipients with proven rejection than in those without (1.76 +/- 0.81 versus 2.95 +/- 1.22 mm Hg-1, p = 0.005). Both, intimal index and circumferential extension of intimal thickening, were significantly higher in recipients following rejection periods (p < 0.05). The extent of coronary vessel wall alterations on ultrasound correlated to donor age but not to perioperative ischemia time, LDL/HDL-ratio and Lp(a). Re-investigation of a subgroup of 13 recipients 67.4 +/- 10.2 weeks after the first study showed an insignificant increase of the intimal index (from 0.03 to 0.09) and of the circumferential extension of intimal thickening (from 40 to 111 degrees). Normalized compliance changed from 2.53 +/- 1.48 to 2.87 +/- 1.33 mm Hg-1 (differences n.s.). Early after orthotopic heart transplantation, a significant correlation between atherosclerotic coronary vessel wall alterations assessed by intravascular ultrasound and donor age can be confirmed. Heart recipients following rejection periods present with significantly more atherosclerotic vessel wall alterations and a severely reduced compliance of the coronary vessels.

Adult↗
PubMed1995

The relation of interleukin-6, tumor necrosis factor-alpha, IL-2, and IL-2 receptor levels to cellular rejection, allograft dysfunction, and clinical events early after cardiac transplantation.

Immunoregulatory cytokines have been implicated in the pathophysiology of graft dysfunction after heart transplantation (HTx). In 15 consecutive patients undergoing HTx we prospectively determined levels of interleukin-6 (IL-6), tumor-necrosis-factor-alpha (TNF-alpha), interleukin-2 (IL-2), and soluble-interleukin-2-receptor (sIL-2-R) at eight points in time during biopsy and right heart catheterization and within 12 hr of echocardiography during the first three months after HTx. Blood was taken from the pulmonary arterial line. IL-6-levels correlated positively with hemodynamic and echocardiographic parameters of pump dysfunction--namely, pulmonary capillary wedge pressure, pulmonary arterial pressure, right atrial pressure, heart rate--and negatively with isovolumic relaxation time and stroke volume independent of the degree of cellular rejection as classified by the ISHLT criteria. A similar pattern was found for TNF-alpha- and sIL-2-R, while IL-2 correlated negatively with left and right heart filling pressures and positively with fractional shortening. In the three patients who died of sepsis or multiorgan failure within the study period IL-6-, TNF-alpha, and sIL-2-R-levels were elevated and IL-2-levels were suppressed compared with the 12 patients with a stable clinical course. IL-6 and sIL-2-R correlated positively while IL-6 and IL-2 correlated negatively. In this pilot study, a cytokine pattern with elevated levels of IL-6, TNF-alpha, and sIL-2-R as well as suppressed levels of IL-2 in the early period after HTx corresponds to impaired hemodynamics independent of cellular rejection and may indicate an unfavorable prognosis. These cytokines may therefore be useful for monitoring and warrant further study.

Adult↗
PubMed1995

Intracoronary stenting after unsuccessful PTCA. Early restenosis and explanation of stents during bypass surgery.

The case of a 63-year-old man is described, who received two intracoronary Palmaz-Schatz-Stents after dissection and occlusion following PTCA of two segments of the left anterior descending branch of the left coronary artery. Because of recurrent angina caused by early restenosis in the 'unprotected' segment between the stents, surgical revascularisation was performed and the stents were removed.

Angina Pectoris↗
PubMed1995

Angiographic, intravascular ultrasound and functional findings early after orthotopic heart transplantation.

Accelerated graft atherosclerosis is responsible for increased mortality and morbidity among heart transplant recipients. The aim of this in-vivo study was to evaluate coronary atherosclerotic vessel alterations and endothelial function. Seventeen patients (14 males; mean age 49.3 years; range 24 to 69) were studied an average of 11 weeks (range 5 to 21) after heart transplantation because of coronary artery disease (n = 8), dilative cardiomyopathy (n = 7), mitral valve replacement (n = 1) and left atrial metastases of a leiomyosarcoma (n = 1). Mean age of the donor hearts (9 males) was 29 years (range 12 to 55). All recipients underwent biplane ventriculography and coronary angiography. In this study population, a total of 120 coronary segments (main stem, 21; left anterior descending artery, 85; circumflex artery, 14) were analyzed by intravascular ultrasound (20 MHz, 3.5F). In 13 patients, acetylcholine was infused into the proximal left anterior descending artery (10(-8) to 10(-5) M) to evaluate vasomotion within this segment. Regional contraction abnormalities were documented in 2 patients. Nine segments angiographically showed non-critical stenoses (5 patients). Intravascular ultrasound detected 52 cross-sectional areas with a three-layer pattern indicating intimal thickening. Mean circumferential extension of intimal proliferation was 192 degrees, mean intimal thickness 0.35 mm. Only 5 segments of the sonographically pathological cross-sectional areas showed angiographical evidence of atherosclerotic lesions. Intracoronary administration of acetylcholine at doses of 10(-8) and 10(-7) M resulted in vasoconstriction of the examined coronary segment in only 2 patients; the intracoronary application of acetylcholine at doses of 10(-6) and 10(-5) M revealed coronary vasoconstriction in 10 of the total of 13 patients. Using intravascular ultrasound, coronary artery lesions in heart transplant recipients can already be depicted at a very early stage. The abnormal response to acetylcholine in most of the heart recipients is independent of the extent of atherosclerotic vessel abnormalities documented by ultrasound or angiography.

Acetylcholine↗
PubMed1995

Clinical and invasive 7-month follow-up of a patient with a synthetic coronary graft.

The PossisR polytetrafluoroethylene Permaflow is a synthetic coronary graft which incorporates a Venturi resistor and which is anastomosed to the superior vena cava. Multiple anastomoses to the coronary vessels can be established in sequence until the graft is finally connected to the aorta. This aortocaval fistula enables permanent flow within the synthetic graft. We present the post-operative clinical and invasive findings of a 69-year-old female patient with a PossisR coronary graft. Follow-up angiography 3 and 7 months post-operatively showed patency of both coronary anastomoses and sufficient run-off to the native vessel segments. The left-right shunt induced by the graft was hemodynamically insignificant. Left ventricular function had improved significantly. 30 MHz intravascular ultrasound of the proximal part of the PossisR graft did not show an extra inner layer at the luminal side of the synthetic graft wall, so that relevant intimal thickening could be excluded after an interval of 7 months post implantation. Using an intravascular imaging technique, focal atherosclerotic lesions or thrombotic graft wall alterations could also be ruled out.

Aged↗
PubMed1995

[Single left coronary artery after orthotopic heart transplantation: angiography and intravascular ultrasound findings].

A 23-year-old man underwent orthotopic heart transplantation due to dilative cardiomyopathy, receiving the heart of a 32-year-old donor. Coronary angiography 7 weeks following transplantation revealed a single left coronary artery arising from the left coronary sinus, and as a coronary abnormality the right coronary artery was originating from the proximal left anterior descending branch. Angiographically the single coronary artery showed no stenoses or irregularities. Intravascular ultrasound examination (30 MHz, 3.5-F catheter) demonstrated relevant atherosclerotic lesions along the stem, the proximal and middle portion of the left anterior descending artery, and especially at the origin of the equivalent of the right coronary artery. Thallium-201 stress testing showed only discrete filling defects at the inferior wall. After orthotopic heart transplantation intravascular ultrasound investigation can, in addition to angiography, become extremely relevant especially in heart recipients with a single left coronary artery because vessel wall alterations of the stem and left anterior descending artery may influence the prognosis of these recipients.

Adult↗