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H H Scheld

Publications and source records attributed to H H Scheld.

At least 217 records · Page 12Linked to original sources
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↗
PubMed1996

[Operations in limited left ventricular pump function].

The proportion of patients with left ventricular dysfunction (LVD) undergoing open heart surgery is increasing. In this patient group, the perioperative risk is elevated because of the preexisting pathophysiology. Detailed evaluation, interdisciplinary differential therapeutic considerations on the basis of the comparative benefit rationale as well as hemodynamic, antiischemic and antiarrhythmic optimization is mandatory. To plan the operation in patients with coronary artery disease, the issue of reversibility of LVD has to be resolved by sophisticated viability testing. The ultimate decision on revascularization versus aneurysmectomy and scar excision has to be met by the operating surgeon. If the patient's hemodynamics is severely compromised, the perioperative risk may be too high and cardiac transplantation, possibly with mechanical bridging, should be considered. If, in addition, intractable malignant tachyarrhythmias are encountered, antitachycardia operation and defibrillator implantation may be performed. During extracorporeal circulation which is associated with a systemic inflammatory response syndrome the compensatory potential is reduced in patients with LVD, and therefore, the risk of complications such as low-output syndrome, respiratory and renal failure is elevated. Advances in the understanding of pathophysiological mechanisms, an individualized preoperative tailored medical and mechanical therapy for preparation of the operation, anesthesiologic management, cardioprotection and postoperative intensive care have contributed to improvement of outcome in this patient group. Specifically patients with documented evidence of myocardial viability such as angina have profited from surgical revascularization as compared to medical therapy in large scale prospective trials. Perioperative mortality has been lowered to 2-20%. In the absence of angina and presence of overt heart failure and arrhythmias, however, the postoperative 3- and 5-year prognosis of 60% and 35%, respectively, continues to be reduced. Improvement of ejection fraction, angina class, functional capacity and quality of life has been documented in all studies. In conclusion, cardiac operations in patients with left ventricular dysfunction can nowadays be performed with a reasonable risk-benefit ratio, if a careful individualized preoperative evaluation and optimal pre-, intra-and postoperative management is performed.

Coronary Disease↗
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

cAMP response element binding protein is expressed and phosphorylated in the human heart.

BACKGROUND: In end-stage failing human hearts and in rat hearts after prolonged in vivo beta-adrenergic treatment, several proteins involved in the cAMP-dependent signal transduction are altered on the protein, mRNA, or transcriptional level, eg, beta-adrenoceptors, G-proteins, or proteins of Ca2+ homeostasis. In many tissues, cAMP-dependent transcriptional regulation occurs through the cAMP response element binding protein (CREB) and related transcription factors binding as dimers to cAMP response elements (CREs) in the promoter regions of regulated genes. METHODS AND RESULTS: To investigate a possible role of CREB in the human heart, nuclear protein of explanted failing and nonfailing human hearts was used to test for CRE specific binding properties in gel mobility shift assays. CRE specific binding was found in competition studies, and CREB and its phosphorylated form were immunologically identified in supershift experiments. The alternatively spliced CREB isoforms CREB327 and CREB341 were found to be expressed on the mRNA level by the reverse transcriptase-polymerase chain reaction. CONCLUSIONS: We conclude that in the failing and nonfailing human heart, CREB is expressed on the protein and mRNA levels and that CREB is phosphorylated and able to bind to CREs, indicating a functional role of CREB in the human heart.

Animals↗
PubMed1995

The Interdisciplinary Heart Failure and Transplant Program Münster: a 5-year experience.

The variety and complexity of therapeutic options available for the increasing number of patients with advanced chronic heart failure has lead to the institution of specialized heart failure/heart transplant programs. The central task consists of carefully evaluating and selecting potential transplant recipients, based on the comparative benefit rationale, i.e. the expected gain in life expectancy and quality of life by cardiac transplantation compared with all other treatment options. Further tasks include a comprehensive chronic heart failure management, high risk conventional cardiac surgery, mechanical and antiarrhythmic bridging and dedicated posttransplant care. This concept is described on the basis of the 5-year experience of the Interdisciplinary Heart Failure and Transplant Program Münster.

Cardiology Service, Hospital↗
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

Arterial and venous cytokine response to cardiopulmonary bypass for low risk CABG and relation to hemodynamics.

During and after cardiopulmonary bypass (CPB), cytokines may affect cardiac performance and the immune response and are therefore of diagnostic and therapeutic interest. We have used EIA/EASIA kits to measure arterial and venous levels of interleukin-1-beta (IL-1-beta), IL-2, IL-2 receptor (IL-2-R), IL-6, tumor necrosis factor (TNF)-alpha and interferon (IFN)-gamma in 12 men and 3 women (mean age 59.4 +/- 8.5 years, mean left ventricular ejection fraction 66 +/- 11%, average of 2.5 +/- 0.64 vessels affected by disease) undergoing elective coronary artery bypass grafting (CABG). On average each patient received 3 +/- 0.85 bypass grafts and required a postoperative maximum dopamine-dose of 3.8 micrograms/kg per min. Mean CPB and operation times were 60 +/- 21 min, and 132 +/- 16 min, respectively. During CPB, the venous levels of IL-2 temporarily decreased from 234 to 0 (p < 0.05) pg/ml and arterial and venous levels of IL-2-R temporarily decreased from 28 to 16, and 36 to 18 pM (p < 0.05), respectively. After termination of CPB, there was an increase in the arterial and venous levels of IL-6 from below 3 to 253 and 277 pg/ml (p < 0.05) and TNF-alpha from 1.1 to 5.7 and 0.7 to 4.0 pg/ml, respectively (p < 0.05). Tumor necrosis factor-alpha-increases peaked 30 min, and IL-6 increases peaked 4 h after termination of CPB. Twenty-four hours after the end of CPB, IL-6 showed a tendency to return to baseline, but still remained significantly elevated.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗
PubMed1995

From the neck to the lung: pneumothorax caused by a lost needle.

The case of a 29-year-old man with a left-sided pneumothorax caused by an injection needle in the lung is presented. The needle had been lost 3 months previously during an attempt to inject heroin into the left jugular vein. With axillary limited thoracotomy after attempted thoracoscopy, the needle was finally found in the left upper lobe of the lung, most probably causing the pneumothorax. At least no other pathologies of the lung were detected and, after surgery, no further pneumothorax occurred. The case is discussed in relation to similar cases described in the medical literature.

Adult↗
PubMed1995

Recurrent bilateral carotid body tumors. A case report on a 'typical' course of a rare disease.

A 34-year-old female patient suffered from bilateral swelling of the neck for more than 10 years until carotid body tumors were diagnosed. In a local hospital, the right-sided tumor was dissected from the carotid arteries, the contralateral tumor was considered unresectable. in our institution, the left cervical mass was completely removed, and 4 years later, recurrency on the right side was similarly operated upon. Due to tumorous infiltration both recurrent nerves, both internal jugular veins, and both the left internal and external carotid artery had to be sacrificed. Carotid boyd tumors are often inadequately treated, despite the simplicity of establishing diagnosis with angiographic and scintigraphic techniques, because they are not included in different diagnosis during assessment.

Adult↗
PubMed1995

Bipolar transvenous defibrillation: efficacy of two different positions of the anode.

For most nonthoracotomy defibrillation lead systems, the transvenous anode can positioned independently of the right ventricular (RV) cathode. Usually a vertical position in the superior vena cava (SVC) is chosen. However, it is unknown if this position yields the optimal defibrillation threshold (DFT). Therefore, in 15 patients undergoing defibrillator implantation the SVC position was compared in a crossover study design with a horizontal position in the left brachiocephalic vein (BCV). Mean DFT was not different for SVC and BCV (19.2 +/- 9.6 J vs 18.5 +/- 9.1 J) but DFT of individual patients differed by up to 12 joules. A positive correlation between impedance and DFT in the BCV position (r = 0.6; P < or = 0.05) indicated that the improved geometry of the defibrillation field with the BCV position is opposed by a higher impedance found for this position (63 +/- 15 omega vs 52 +/- 7 omega). Thus, defibrillation is not improved in general although individual patients might benefit.

Aged↗
PubMed1995

Internal defibrillation with smaller capacitors: a prospective randomized cross-over comparison of defibrillation efficacy obtained with 90-microF and 125-microF capacitors in humans.

INTRODUCTION: The size of current implantable cardioverter defibrillators (ICD) is still large in comparison to pacemakers and thus not convenient for pectoral implantation. One way to reduce ICD size is to defibrillate with smaller capacitors. A trade-off exists, however, since smaller capacitors may generate a lower maximum energy output. METHODS AND RESULTS: In a prospective randomized cross-over study, the step-down defibrillation threshold (DFT) of an experimental 90-microF biphasic waveform was compared to a standard 125-microF biphasic waveform. The 90-microF capacitor delivered the same energy faster and with a higher peak voltage but provided only a maximum energy output of 20 instead of 34 J. DFTs were determined intraoperatively in 30 patients randomized to receive either an endocardial (n = 15) or an endocardial-subcutaneous array (n = 15) defibrillation lead system. Independent of the lead system used, energy requirements did not differ at DFT for the experimental and the standard waveforms (10.3 +/- 4.1 and 9.5 +/- 4.9 J, respectively), but peak voltages were higher for the experimental waveform than for the standard waveform (411 +/- 80 and 325 +/- 81 V, respectively). For the experimental waveform the DFT w as 10 J or less using an endocardial lead-alone system in 10 (67%) of 15 patients and in 12 (80%) of 15 patients using an endocardial-subcutaneous array lead system. CONCLUSIONS: A shorter duration waveform delivered by smaller capacitors does not increase defibrillation energy requirements and might reduce device size. However, the smaller capacitance reduces the maximum energy output. If a 10-J safety margin between DFT and maximum energy output of the ICD is required, only a subgroup of patients will benefit from 90-microF ICDs with DFTs feasible using current defibrillation lead systems.

Adolescent↗
PubMed1995

Benefits of treatment with implantable cardioverter-defibrillators in patients with stable ventricular tachycardia without cardiac arrest.

BACKGROUND: The availability of implantable cardioverter-defibrillators (ICD) that are capable of antitachycardia pacing may lead to an increased use of ICDs in patients with haemodynamically tolerated ventricular tachycardia without a history of cardiac arrest. The frequency of potentially life-threatening fast ventricular tachycardias (cycle length < 250 ms) was investigated in patients who had a third generation ICD with endocardial leads implanted because they had haemodynamically tolerated ventricular tachycardia without a history of cardiac arrest. METHODS: Between January 1990 and October 1993, 50 patients (age (mean (SD)) 60 (11); ejection fraction 39 (16)%; 82% with coronary artery disease and 8% with dilated cardiomyopathy) with haemodynamically tolerated ventricular tachycardia (cycle length (mean (SD)) 348 (60) ms; range 250-500 ms) and without a history of cardiac arrest were treated with third generation ICDs that were capable of antitachycardia pacing. Fast ventricular tachycardia had been induced in 14 (28%) during baseline electrophysiological study. The benefit of ICD treatment was estimated as the difference between total mortality and the occurrence of fast ventricular tachycardia that would have been fatal if it had not been terminated. RESULTS: During follow up of 17 (12) months, 33 patients (66%) had a total of 3861 episodes of ventricular tachycardia. 91% of these episodes were terminated by antitachycardia pacing. 11 patients (22%) had episodes of potentially life-threatening fast ventricular tachycardia and 3 of these also had inducible fast ventricular tachycardia. One patient died suddenly 27 months after implantation. The difference between survival without fast ventricular tachycardia and total mortality was 9%, 12%, 27%, and 27% at 6, 12, 18, and 24 months, respectively. CONCLUSIONS: About a fifth of patients who had been given an ICD to treat haemodynamically tolerated ventricular tachycardia and who had no history of cardiac arrest experienced fast ventricular tachycardia during follow up requiring immediate cardioversion. Prospective studies are needed to investigate whether the prognosis of patients with a history of haemodynamically tolerated ventricular tachycardia without cardiac arrest is improved by ICD therapy.

Cardiomyopathy, Dilated↗
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↗
PubMed1995

[Initial experiences with dobutamine stress echocardiography in heart transplant patients].

UNLABELLED: Cardiac allograft vasculopathy (CAV) has become one of the primary obstacles to long-term survival of patients after heart transplantation. The low sensitivity of currently available noninvasive tests still remains a problem in the early diagnosis of the disease. To assess the feasibility, safety, and usefulness of dobutamine stress echocardiography as a noninvasive predictor of cardiac allograft vasculopathy, we examined 20 patients (3 female) 3-35 months after orthotopic heart transplantation. All patients underwent coronary angiography within 2 weeks of dobutamine stress echocardiography. RESULTS: 89% of the segments examined could be evaluated for wall motion abnormalities. Under increasing doses of dobutamine (5 to max. 30 micrograms/kg/min), heart rate increased from 88 +/- 13 bpm to 141 +/- 16 bpm. and systolic blood pressure from 139 +2- 14 mm Hg to 154 +/- 28 mm Hg. Two of 4 patients with angiographically detected CAV developed new wall motion abnormalities under dobutamine; their wall motion score increased from 1.23 +/- 0.22 to 1.31 +/- 0.24. In the other patients without CAV, the wall motion score remained almost unchanged (1.01 +/- 0.3 to 1.02 +/- 0.4). Dobutamine was well tolerated, and there were no serious complications. Thus, dobutamine stress echocardiography seems to be feasible and safe in patients after heart transplantation. Our results suggest that it might be useful for the detection of cardiac allograft vasculopathy. The final determination of its clinical usefulness in the diagnosis of cardiac allograft vasculopathy needs further extensive investigations.

Adult↗