High incidence of inappropriate alarms in patients with wearable cardioverter-defibrillators: findings from the swiss WCD registry

Introduction

The wearable cardioverter defibrillator (WCD) uses surface electrodes built into the vest to detect underlying arrhythmia before initiating a treatment sequence. However, it is also prone to inappropriate detection due to artefacts.

Purpose

The aim of this study was to assess the alarm burden in patients and its possible impact on clinical outcomes.

Methods

The Swiss WCD Registry is a nationwide, retrospective, observational registry. Patients were included from December 2011 until February 2018. Clinical characteristics and data from the WCDs, including alarm burden were analysed. Recordings ≥30 seconds of length were analysed and categorized as VT/VF, atrial fibrillation (AF), supraventricular tachycardia or artefact.

Results

A total of 10'653 device alarms were documented in 324 of 456 patients (71.1%) over a mean WCD wear-time of 2.0±1.6 months. Among these, the episode duration was 30 seconds or more in 2996 (28.2%). One hundred and eleven (3.7%) were VT/VF episodes. The remaining recordings were inappropriate arrhythmia detections (2736 (91%) due to artefacts; 117 (3.7%) AF; 48 (1.6%) supraventricular tachycardia). Two-hundred and seven patients (45.0%) had 3 or more alarms per month, whereas 49 patients (10.7%) had 1 or more alarms per day. Body mass index (BMI) was significantly higher in patients with 3 or more alarms per month (p=0.002, 25.6 vs. 27.3 kg/m2) High alarm burden was not associated with a lower average daily wear time (20.8 hours vs 20.7 hours, p=0.785) or a decreased implantable cardioverter defibrillator implantation rate after stopping WCD use (48% vs 47.3%, p=0.156).

Conclusions

In patients using WCDs, alarms emitted by the device and impending inappropriate shocks were frequent and most commonly caused by artefacts. A high alarm burden did not lead to a decreased adherence, as determined by average daily wear-times. Obesity was significantly associated with a higher alarm burden.

Funding Acknowledgement

Type of funding sources: None.

A novel variant in the SLC4A3 gene with high penetrance in a family with short QT Syndrome

Funding Acknowledgements

Type of funding sources: None.

Background

Short QT syndrome (SQTS) is a rare, autosomal dominant disease causing sudden cardiac death (SCD). Current guidelines recommend genetic testing. Associated variants in KCNQ1, KCNH2, KCNJ2 and SLC4A3 genes have been reported.

Purpose

We report a family with a variant in the SLC4A3 gene with several presentations of SCD and high clinical penetrance of SQTS.

Methods

We performed a post-mortem genetic testing in the index patient in whom prior ECG was available. Subsequently, clinical and electrophysiological work-up and cascade screening (CS) of the detected suspected variant was carried out in available relatives.

Results

The index patient had suffered a SCD at the age of 17 (figure, upper panel, arrow). A previously registered ECG showed a shortened QTc of 340ms (figure, lower panel). Autopsy revealed no structural heart disease. Post-mortem genetic testing revealed variants in the LDB3, MYH7 and a novel heterozygous missense variant, p.(Ser1039Arg) also in the SLC4A3 gene. Although predictive bioinformatic algorithms (AlignGVGD, SIFT, MutationTaster, Polyphen2) showed conflicting classifications, family history was notable for SCD without post-mortem genetic work-up in three second degree relatives (figure, upper panel, patients 207, 208 and 305, age of death 33, 25 and 33 years respectively). CS was performed in first and second degree relatives of the index patient and was highly suggestive for disease association of the variant in the SLC4A3 gene with co-segregation in all clinically affected family members. Only one patient with the variant had a normal QTc (figure, upper panel, patient 202) of 407ms, however this patient was on regular QT-prolonging medication (risperidone and loperamide).

Conclusion

Genetic testing revealed a novel in the SLC4A3 gene, which was recently implicated in the pathogenesis of the SQTS. Although predictive bioinformatic algorithms yielded conflicting results, CS of family members suggests a likely pathogenicity (class IV) of the variant. Further CS or functional tests are necessary to establish causality. Abstract Figure. ECG of index patient and family tree

A novel diagnostic score to differentiate between athlete"s heart and ARVC

Funding Acknowledgements

Type of funding sources: None.

Background

The 2010 Task Force Criteria (TFC), although representing the current gold standard to diagnose arrhythmogenic right ventricular cardiomyopathy (ARVC), have not been tested to differentiate ARVC from the athlete’s heart. Furthermore, not all 6 diagnostic categories are easy to obtain.

Purpose

We hypothesized that atrial dimensions are useful to differentiate between both entities. Therefore, we developed a new diagnostic score based upon readily available clinical parameters including atrial dimensions on TTE to help distinguishing the athlete’s heart from ARVC in daily clinical practice.

Methods

In this observational study, 37 patients with definite ARVC (from the Zurich ARVC Program) were compared to 68 athletes. Base on ROC analysis, the following echocardiographic, laboratory and electrocardiographic parameters were included in the final score: indexed right/left atrial volumes (RAVI/LAVI ratio), NT-proBNP, RVOT measurements (PLAX and PSAX adjusted for BSA) on TTE, tricuspid annular motion velocity (TAM) on TTE, precordial electrocardiographic T-wave inversions and depolarization abnormalities according to the TFC.

Results

ARVC patients had a higher RAVI/LAVI ratio (1.78 ± 1.6vs0.95 ± 0.3,p < 0.001), lower right-ventricular function (fac:28 ± 9.7vs42.1 ± 4.8%,p < 0.001; TAM:17.9 ± 5.6vs23.3 ± 3.7mm,p < 0.001) and higher serum NT-proBNP levels (491 ± 771vs44.8 ± 50.6ng/l,p < 0.001). Our novel score outperformed the performance of the 2010 TFC using those parameters, which are available in routine clinical practice (AUC95%,p < 0.001(95%CI.91-.99)vs.AUC90%,p < 0.001(95%CI.84-.97). A score value of 7/12 points yielded a specificity of 98% and a sensitivity of 61% for a diagnosis of ARVC.

Conclusions

ARVC patients present with significantly larger RA as compared to athletes, resulting in a greater RAVI/LAVI ratio. Our novel diagnostic score includes readily available clinical parameters and has a high diagnostic accuracy to differentiate between ARVC and the athlete´s heart. Abstract Figure. Novel clinical score

Two novel variants in the SLC4A3 gene in two families with Short QT Syndrome: the role of cascade screening

Background

Short QT syndrome (SQTS) is a rare, autosomal dominant disease causing sudden cardiac death (SCD). Genetic testing is recommended according to current guidelines. Variants in KCNQ1, KCNH2, KCNJ2 and SLC4A3 genes have been reported in SQTS.

Purpose

We report implications of genetic testing and cascade screening (CS) in two families with phenotypical presentation of SQTS and novel genetic variants of unknown significance.

Methods

We performed a thorough clinical and electrophysiological work-up of the index patients of both families. In addition, genetic screening was conducted. Subsequently, segregation analysis of potentially pathogenic variants was carried out in available relatives.

Results

Index patient 1 presented with a history of recurrent syncope. His ECG showed a shortened QTc of 340ms. Family history was unremarkable. Structural heart disease was excluded by cardiac MRI and coronary angiography. Genetic testing detected a rare heterozygous missense variant in the KCNH2 gene (p.(Arg328Cys), frequency 0.053%), predicted to be pathogenic according to various prediction algorithms (Polyphen, SIFT, Align GVGD, mutation taster). CS of relatives did not confirm this variant as the causative mutation. Reanalysis of whole-exome sequencing data revealed a novel heterozygous missense variant, p.(Arg370Cys) in the recently identified SLC4A3 gene. A variant at the same position has previously been associated with SQTS. CS suggested disease association. The second index patient had a SCD at the age of 17. A previously registered ECG showed a shortened QTc of 340ms. Autopsy revealed no structural heart disease. Post-mortem genetic testing revealed variants in the LDB3, MYH7 and a novel heterozygous missense variant, p.(Ser1039Arg) also in the SLC4A3 gene. Family history was positive for SCD in three 2° relatives. The index patient's father had a positive phenotype with a QTc of 365ms. CS again suggested disease association of the variant in the SLC4A3 gene only.

Conclusion

Genetic testing revealed two novel variants in the SLC4A3 gene, which was recently implicated in the pathogenesis of the SQTS. Predictive bioinformatic algorithms to assess the pathogenicity of missense variants are of limited relevance, but genetic analysis of additional unaffected and affected family members may be instrumental to identify pathogenic DNA sequence variations.

Family tree index patients 1 and 2

Funding Acknowledgement

Type of funding source: None

First two MRI guided stereotactic body radiation therapy of recurrent sustained ventricular tachycardia

Background

Stereotactic body radiation therapy (SBRT) is emerging as a bail-out treatment in patients suffering from therapy resistant ventricular tachyarrhythmias (VT).

Purpose

We report the worldwide first cases of real-time magnetic resonance image guided SBRT (MR-SBRT) in recurrent sustained VT and electrical storm (ES) due to dilated cardiomyopathy (DCM).

Methods

The patients were male, 71- (patient A) and 74-year-old (patients B) suffering from recurrent VT and ES with ICD shocks, despite guideline-directed medical therapy including maximal antiarrhythmic therapy. Patient A had two endocardial radiofrequency catheter ablation (RFA) and one epicardial surgical RFA and patient B had one endocardial RFA prior. An interdisciplinary decision was made to perform MR-SBRT in palliative intent to minimize repetitive ICD shocks.

Results

Areas of VT-substrate were identified to build a volumetric target using the performed EP studies as well as cardiac MRI and CT. A single fraction of 25Gy at isodose 80% was delivered to a planned target volume of 115.1ml and 73ml in the anterior/anteroseptal basal regions in patients A and B, respectively on a dedicated MR linac using real-time MRI tracking. Patient A developed a prolonged ES interpreted as acute radiation-induced inflammation following the treatment, which ceased two days after administration of high-dose dexamethasone. Patient B had no immediate adverse effects from the treatment. Left-ventricular ejection fraction remained stable in both patients at 25%. Both patients had significant improvement of their quality of life. Patient A died 222 days after MR-SBRT due to recurrent ES at another hospital. Patient B is free from VT over six months after treatment.

Conclusion

In these first two cases, we demonstrate feasibility, safety and short-term efficacy of MR-SBRT.

ICD therapies before and after MR-SBRT

Funding Acknowledgement

Type of funding source: None

911Which patients are most likely to benefit from the wearable cardioverter-defibrillator? Findings from the Swiss WCD registry

OnBehalf

Swiss WCD Registry

Introduction

 The wearable cardioverter-defibrillator (WCD) has established itself as a temporary protection from sudden arrhythmogenic death in selected patients at risk. However, it is still of debate which patients and for what duration benefit from its use. Therefore, appropriate patient selection is key. Purpose: This study reports the results of the Swiss WCD registry with an emphasis on implantable cardioverter-defibrillator (ICD) implantation rate and ICD therapies.

Methods

 We retrospectively reviewed the indications, baseline characteristics and administered therapies in patients prescribed a WCD at 12 participating centers rom 2014 until 2018 in Switzerland. Further data on medical therapy, WCD therapy adherence, and ICD implantation rates were collected. 

Results

 456 patients were included in our study comprising of 66% of all Swiss patients prescribed a WCD in the examined time period. The mean age was 57 ±14 years, 18% were female and the mean ejection fraction (EF) was 32% ± 13. Indications for WCD use and appropriate shock rate are shown in the figure. Patients wore the WCD over a median of 58 days (range 1-455) with a median daily average wear-time of 22.6 hours (range 0.6-23.8). 17 appropriate therapies were administered by the WCD to a total of 12 patients leading to a therapy rate of 2.6% over a median wear-time of 16 days (range 2-79) and to a therapy rate of 3.9% in patients with ischemic cardiomyopathy (ICM) with an EF ≤35%. ICM with an EF ≤35% and bridging to ICD-implantation or heart transplantation as indication for WCD prescription were significantly associated with an appropriate therapy (p = 0.046 and 0.003, respectively). One patient with non-ischemic cardiomyopathy (NICM) received an appropriate therapy (0.8%). The mean EF in patients receiving an appropriate therapy by the WCD was also significantly lower (p = 0.04). No patient with wearing the WCD for congenital/inherited heart disease or risk stratification with an EF >35% had a therapy administered by the WCD. There were no inappropriate therapies during the investigated time period. After cessation of WCD use EF improved to 38% ±13; ultimately, 212 patients (46%) were implanted with an ICD. During a follow-up of 476 days (range 7-2347) 22 (9.8%) patients received an appropriate therapy by their ICD. Four of the 22 had prior appropriate therapy by the WCD.

Conclusions

 ICM with severely reduced EF was the most common indication for WCD use leading to a high rate of appropriate therapy by the WCD. This, however, did not translate in a higher rate of appropriate ICD-therapies during follow-up in this subpopulation possibly due to significant improvements in their ejection fractions. Patients with NICM or congenital/inherited heart disease seldom had an appropriate therapy by the WCD.

Abstract Figure. Indications for WCD use and therapy rate

1268A family with a novel variant in the SLC4A3 gene leading to short QT phenotype - the importance of whole-exome-sequencing and cascade screening

Funding Acknowledgements

none

Introduction

 Short QT syndrome (SQTS) is a rare, autosomal dominant disease causing ventricular fibrillation and sudden cardiac death. Genetic testing is recommended according to current guidelines. Mutations in KCNQ1, KCNH2, KCNJ2 and more recently SLC4A3 genes have been implicated in SQTS. These genes encode potassium channel subunits and a bicarbonate transporter regulating intracellular pH. A dominant mutation in this transporter can lead to increased intracellular pH and shortened action potential.

Purpose

 We present a family with a short QT phenotype and recurrent syncope in whom a novel genetic variant was detected by whole-exome sequencing (WES), confirmed by cascade screening.

Methods

 We performed a thorough work-up of the index patient including medical history, physical examination, 12-lead ECG, echocardiography, stress testing, coronary angiography, flecainide challenge, and genetic testing with NGS. QTc was determined using Bazett’s formula. CS of all 1° and two 2° relatives was performed.

Results

 The ECG of the index patient showed a QTc of 340ms and characteristics compatible with a SQTS (figure). Clinical work-up was unremarkable. A first genetic search with next generation sequencing focusing on genes that have been previously involved in the pathogenesis of channelopathies detected a rare known heterozygous missense variant in the KCNH2 gene (Arg328Cys, frequency 0.053%), which was predicted to be pathogenic according to various prediction algorithms (Polyphen, SIFT, Align GVGD, mutation taster). ECG screening of all asymptomatic first-degree family members identified a SQT phenotype in the mother (QTc 355ms), but not in the father (QTc 380ms) and sister (410ms). The KCNH2 variant was found in the father and sister but not the affected mother, which excludes this variant as the causative mutation in this family. Therefore, reanalysis of WES data was performed and revealed a novel heterozygous missense variant p.(Arg370Cys) in the SLC4A3 gene, recently associated with SQTS. A mutation in this gene at the same position has been previously reported in SQTS. The p.(Arg370Cys) mutation was found in the mother but not in the unaffected father or sister. Furthermore the mutation was present in two affected maternal uncles (QTc 319ms and 342ms) supporting the assumption that this was the causative mutation in this family.

Conclusions

 A novel genetic variant in the SLC4A3 gene leading to sQT phenotype could be detected using WES and cascade screening. Predictive bioinformatic algorithms to assess the pathogenicity of missense variants are of limited relevance, but genetic analysis of additional unaffected and affected family members may be instrumental to identify pathogenic DNA sequence variations.

Abstract Figure. Pedigree and ECGs of the family

Thoracoabdominal pressure gradient and gastroesophageal reflux: insights from lung transplant candidates

Advanced lung disease is associated with gastroesophageal reflux disease (GERD). The thoracoabdominal pressure gradient (TAPG) facilitates gastroesophageal reflux, but the effects of TAPG on gastroesophageal reflux in patients with pulmonary disease have not been well defined. Patients diagnosed with end-stage lung disease are expected to have the most extreme derangement in respiratory mechanics. The aim of this study is to explore the relationship between TAPG and reflux in lung transplant (LTx) candidates. We reviewed LTx recipients who underwent pretransplant esophageal high-resolution manometry and a 24-hour pH study. Patients were excluded if they were undergoing redo LTx, had manometric hiatal hernia, or had previously undergone foregut surgery. TAPG was defined as the intra-abdominal pressure minus the intrathoracic pressure during inspiration. Adjusted TAPG was calculated by the TAPG minus the resting lower esophageal sphincter (LES) pressure (LESP). Twenty-two patients with normal esophageal function tests (i.e., normal esophageal motility with neither manometric hiatal hernia nor pathological reflux on 24-hour pH monitoring) were selected as the pulmonary disease-free control group. In total, 204 patients underwent LTx between January 2015 and December 2016. Of these, 77 patients met inclusion criteria. We compared patients with obstructive lung disease (OLD, n = 33; 42.9%) and those with restrictive lung disease (RLD, n = 42; 54.5%). 2/77 patients (2.6%) had pulmonary arterial hypertension. GERD was more common in the RLD group than in the OLD group (24.2% vs. 47.6%, P = 0.038). TAPG was similar between the OLD group and the controls (14.2 vs. 15.3 mmHg, P = 0.850); however, patients in the RLD group had significantly higher TAPG than the controls (24.4 vs. 15.3 mmHg, P = 0.002). Although TAPG was not correlated with GERD, the adjusted TAPG correlated with reflux in all 77 patients with end-stage lung disease (DeMeester score, rs = 0.256, P = 0.024; total reflux time, rs = 0.259, P = 0.023; total number of reflux episodes, rs = 0.268, P = 0.018). Additionally, pathological reflux was seen in 59.1% of lung transplant candidates with adjusted TAPG greater than 0 mmHg (i.e., TAPG exceeding LESP); GERD was seen in 30.9% of patients who had an adjusted TAPG ≤ 0 mmHg. In summary, TAPG varies based on the underlying cause of lung disease. Higher adjusted TAPG increases pathological reflux, even if patients have normal antireflux anatomy and physiology (i.e., no hiatal hernia and manometrically normal LES function). Adjusted TAPG may provide further insights into the pathophysiology of GERD.

[Nellix® endovascular aneurysm sealing (EVAS) - a new technology for endovascular management of infrarenal aortic aneurysms]

BACKGROUND

Recently used endografts for envascular aneurysm repair (EVAR) exclude the pathology by fixation at both the proximal and distal landing zone. Due to endoleaks and migration EVAR is associated with a relevant rate of secondary interventions. The Nellix® system (Endologix Inc., CA, USA) was developed to seal the complete aneurysm using a polymer filling, therefore stabilising endograft-position and reducing the rate of endoleaks and reinterventions. The present contribution introduces the method, describes the technique of implantation and presents the first clinical results. Material und Methods: The Nellix system consists of two balloon-expandable stent grafts made of a cobalt-chromium composition, surrounded with ePTFE and the so-called endobags. During the implantation each endobag is filled with a non-biodegradable polymer, sealing the aneurysm lumina including the proximal and distal landing zone. Hence, lumbar arteries will be sealed to reduce the probability of a type II endoleak.

RESULTS

Longterm durability as well as the structural integrity of the Nellix system has been proven over 4 years in sheep experiments. The technical success in a multicentre, prospective registry was 94% without the appearance of severe adverse events (migration, occlusion, secondary endoleak).

CONCLUSION

EVAS is a new and different concept of endovascular AAA repair. Recent clinical data of the Nellix system are promising showing a high technical success rate while the need for secondary intervention is low. Further studies in larger cohorts are needed.

Phacoemulsification on previously vitrectomized eyes: results of a 10-year-period

PURPOSE

To provide an overview of intraoperative and postoperative complications during phacoemulsification cataract surgery and to evaluate the visual results in patients having pars plana vitrectomy (PPV) with 10 years of follow-up.

METHODS

Retrospective evaluation of intraoperative and postoperative complications and postoperative visual results in 134 consecutive patients who underwent phacoemulsification after PPV. Of 11,498 eyes treated with phacoemulsification, 143 (1.2%) had previous PPV during the 10-year period were included in this study.

RESULTS

The phacoemulsification procedure seemed to be difficult where there was a deep or fluctuating anterior chamber (93%) and primary posterior capsule opacification (19%). The most frequent intraoperative complications were posterior capsule rupture (9%) and incomplete capsular rhexis (5%). Postoperative intraocular pressure elevation (7%), retinal detachment (6%), and posterior capsule opacification (8%) occurred most frequently during the mean follow-up period of 18.2 months (1.5-110 months). Best-corrected visual acuity (BCVA) increased two or more Snellen E lines in 55% of the cases or became better than or equal to 0.5 in 10% of the cases.

CONCLUSIONS

Despite the well-known difficulties encountered in vitrectomized eyes such as zonular damage, increased mobility of the lens-iris diaphragm, and altered intraocular fluid dynamics, phacoemulsification proved to be a safe procedure in the hands of experienced surgeons.

Prostate Cancer Screening

Prostate cancer incurs a substantial incidence and mortality burden, similarly to breast cancer, and it ranks among the top ten specific causes of death in the United States. It is inherent as we maximize the detection of early prostate cancer that we increase the detection of both nonaggressive (slow growing) and aggressive (faster growing) prostate cancers. The evidence clearly supports the use of PSA screening in conjunction with DRE as a means of early detection of prostate cancer. Widespread implementation of prostate cancer screening in the United States has led to the phenomenon of stage migration with more cancers being detected at a lower stage. Such a trend has decreased the incidence of metastatic disease at diagnosis and paralleled the decrease of the mortality rate from prostate cancer. Our understanding of the natural history of prostate cancer is progressing over time, but the question of its length is unanswerable. The relatively long doubling time (on average) of early prostate cancer of 3 to 4 years or more indicates a relatively good prognosis for many men with this disease, even without early detection and treatment. Unfortunately, the poor specificity of the PSA test in men with benign prostatic hyperplasia (BPH) leads to high rates of prostate biopsy and attendant illnesses and costs. Early detection is more apt to detect a slow-growing prostate cancer than a faster growing cancer that is associated with a more rapid course of progression to metastatic disease. Hence, the launching of mass screening programs for the early detection of prostate cancer is premature. However, in the absence of solid evidence of benefit, one reasonable approach to screening at the individual level is to involve the patient in decisions about whether or not to perform a PSA test. Thus, "offering" PSA testing must be accompanied by informed discussion within the context of an ongoing patient-physician relationship. This is to be distinguished from the use of PSA testing for the purpose of "mass screening." Concepts that must be explored with the patient include: 1. The long-term ramifications of screening 2. The relatively high probability of further evaluation and biopsy with positive results 3. Potentially difficult decisions that may arise about using treatments that are associated with considerable morbidity and uncertain benefits (at the time) if cancer is discovered We should identify a future path that is evidence-based, focused on the issues that make a difference to patients, and results in better and longer lives of those with the disease and those who are at risk of getting it. If that path leads to treating fewer patients in the future, even if sometimes more aggressively, we should pursue it definitely and consequently.

Change of foveal and perifoveal thickness measured by OCT after phacoemulsification and IOL implantation

PURPOSE

Cataract surgery is known to elicit postoperative macular oedema owing to its traumatic effect. The aim of the study was to measure the foveal and perifoveal thickness of the retina after uneventful phacoemulsification and posterior chamber intraocular lens (PC-IOL) implantation.

METHODS

Retinal thickness values of the foveal and perifoveal (fovea+3.0 mm, fovea+6.0 mm) sectors and the minimum values were measured in a prospective study using optical coherence tomography (OCT) in 71 eyes of 71 patients (34 men, 37 women, mean age: 68.8 years) who underwent cataract surgery. Phacoemulsification and 'in the bag' implantation of a foldable PC-IOL was performed under topical anaesthesia. Data were collected 1 day before the operation, and postoperatively at 1, 7, 30, and 60 days. Contralateral eyes of each patient served as controls. 'Student's t-test' was used for statistical analysis, and P<0.05 value was considered significant.

RESULTS

No significant change of the thickness values could be measured 1 day after surgery. However, a significant increase could be detected on the postoperative 7, 30, and 60 days in the perifoveal 3.0 and 6.0 mm sectors either calculated alone or averaged together with the foveal values. The initial (preoperative) average value of 234.1+/-2.6 microm (mean+/-SEM, n=536) in the 6.0 mm perifoveal region increased to 242.5+/-2.6 microm (mean+/-SEM, n=488, P<0.01) 1 week, to 247.7+/-4.6 microm (n=352, P<0.01) 1 month, and to 246.0+/-5.9 microm (n=208, P<0.05) 2 months after surgery, which proved to be significant. However, the relative change of macular thickness was moderate, 3.5, 5.6, and 5.3% at the above periods, respectively. In a subgroup of patients (n=34) minimum 6 months after cataract surgery, the 6.0 mm perifoveal values were found to be elevated at (237.8+/-3.9 microm, mean+/-SEM, n=272) as compared to the control eyes (233.9+/-3.8 microm, mean+/-SEM, n=272). The difference was 1.7% and proved not to be significant (P>0.05).

CONCLUSIONS

Mild subclinical perifoveal oedema following cataract surgery was detected using OCT at postoperative day 7 to 6 months. The minimal and the foveal values in itself are inadequate to describe the phenomenon. The macular thickness values of the perifoveal 3.0 and 6.0 mm sectors alone or averaged together with the foveal values provide more accurate description of the postoperative macular oedema.OCT enables the detection of minimal increases in perifoveal retinal thickness even 6 months after cataract surgery.

The role of biofilm infection in urology

In the process of endourological development a great variety of foreign bodies have been invented besides urinary catheters on which biofilm can be formed. Bacteria in the biofilm are less sensible to antibiotics. An additional problem of medical biomaterials in the urinary tract environment is the development of encrustation and consecutive obstruction. In this review, we tried to sum up the conditions where biofilm formation has a great impact on the development or maintenance of urological infections and on treatment success. Modification of the biomaterial surface seems to be the most promising prevention strategy for bacterial biofilms. Easier methods for diagnosing and quantifying biofilm infection, to develop more specific antimicrobial agents and ideal device surfaces would surely help the fight against biofilm formation.

Improvement of visual functions and fundus alterations in early age-related macular degeneration treated with a combination of acetyl-L-carnitine, n-3 fatty acids, and coenzyme Q10

The aim of this randomized, double-blind, placebo-controlled clinical trial was to determine the efficacy of a combination of acetyl-L-carnitine, n-3 fatty acids, and coenzyme Q10 (Phototrop) on the visual functions and fundus alterations in early age-related macular degeneration (AMD). One hundred and six patients with a clinical diagnosis of early AMD were randomized to the treated or control groups. The primary efficacy variable was the change in the visual field mean defect (VFMD) from baseline to 12 months of treatment, with secondary efficacy parameters: visual acuity (Snellen chart and ETDRS chart), foveal sensitivity as measured by perimetry, and fundus alterations as evaluated according to the criteria of the International Classification and Grading System for AMD. The mean change in all four parameters of visual functions showed significant improvement in the treated group by the end of the study period. In addition, in the treated group only 1 out of 48 cases (2%) while in the placebo group 9 out of 53 (17%) showed clinically significant (>2.0 dB) worsening in VFMD (p = 0.006, odds ratio: 10.93). Decrease in drusen-covered area of treated eyes was also statistically significant as compared to placebo when either the most affected eyes (p = 0.045) or the less affected eyes (p = 0.017) were considered. These findings strongly suggested that an appropriate combination of compounds which affect mitochondrial lipid metabolism, may improve and subsequently stabilize visual functions, and it may also improve fundus alterations in patients affected by early AMD.

Crosslinking of Fas/CD95 suppresses the CD3-mediated signaling events in Jurkat T cells by inhibiting the association of the T-cell receptor zeta chain with src-protein tyrosine kinases and ZAP70

Crosslinking of Fas (APO-1/CD95) on the surface of T cells initiates a biochemical cascade leading to programmed cell death. We have previously shown that crosslinking of Fas with an apoptosis-inducing IgM anti-Fas mAb results in suppression of the CD3-initiated cell signaling including Ca2+ mobilization and protein tyrosine phosphorylation. We conducted experiments to decipher the mechanisms whereby the cross talk between the Fas- and CD3 signaling pathways occur. We used lysates from Jurkat T and examined the composition of the TCR zeta chain-precipitated immune complexes using immunoblots. While crosslinking of Fas affected the association of p59fyn and p56lck tyrosine kinases with the TCR zeta chain to a limited degree, it dramatically inhibited the association of the protein tyrosine kinase ZAP70 with the zeta chain. In cells that were preincubated with an apoptosis-inducing anti-Fas mAb, the binding of the protein tyrosine phosphatases SHP-1 to the TCR zeta chain was increased. These experiments indicate that crosslinking of Fas interferes with early T cell signaling events by promoting the recruitment of SHP-1 and decreasing the association of protein tyrosine kinases with TCR zeta chain. Therefore, crosslinking of Fas antigen may regulate the antigen-induced T cell response and play an active role in the T cell anergy.

C1 inhibitor prevents capillary leakage after thermal trauma

OBJECTIVE

In burned patients, activation of the complement and clotting systems is suggested to play an important role in the development of the capillary leak syndrome and inflammatory tissue destruction. In an animal model of thermal trauma, the possible protective effect of C1 inhibitor (C1Inh), a major control protein of both the complement and clotting systems, was investigated.

DESIGN

Prospective, controlled study.

SETTING

Animal model.

SUBJECTS

Healthy pigs weighing 30 kg.

INTERVENTIONS

Pigs were scalded for 25 secs with 75 degrees C hot water to achieve a 30% total body surface deep partial-thickness burn. The treatment group (n = 8) received C1Inh concentrate at an initial dose of 100 units/kg body weight immediately after thermal trauma, followed by three further applications every 12 hrs. Two control groups included animals that were either scalded (n = 8) or not scalded (n = 7) and treated with lactated Ringer's solution.

MEASUREMENTS

Before and at various time points after trauma blood samples were analyzed for complement activation (APH50, CH50, SC5b-9, C3). Continuous monitoring of hemodynamic variables was performed and postmortem histologic examination of specimens from lung, heart, liver, kidney, stomach, duodenum, jejunum, ileum, and colon was carried out. Aseptically collected mesenteric lymph nodes were pooled and screened for bacterial translocation. For evaluation of the burn wound, biopsies from defined scalded and not scalded areas were taken daily. As a measure for edema formation, the weight of the animals was recorded every 2 hrs.

RESULTS

After C1Inh treatment, which led to a significantly reduced complement activation, the clinical outcome was clearly improved, as indicated by vital signs and as demonstrated by reduced edema formation. Treated animals presented a diminished bacterial translocation. Pathologic alterations were clearly diminished in the burned skin, in shock-related organs, and in the intestines.

CONCLUSION

Application of C1Inh appears to be an effective means to prevent capillary leakage and inflammatory tissue destruction after thermal trauma.

Transverse myelopathy in systemic lupus erythematosus: an analysis of 14 cases and review of the literature

OBJECTIVE

To give a comprehensive review of transverse myelopathy (TM), a rare but serious condition reported in 1-2% of patients with systemic lupus erythematosus (SLE).

METHODS

14 patients with SLE and TM were evaluated and 91 additional cases published in the English and German literature reviewed.

RESULTS

TM presented either as the initial manifestation or within five years of the diagnosis of SLE. Most patients presented with a detectable sensory deficit at the thoracic level. In our 14 patients, 22% of the patients showed complete neurological recovery, whereas in the total patient population of 105 (our cases plus those reviewed in the literature), complete recovery was observed in 50%, partial recovery in 29% and no improvement or deterioration in 21%. Treatment with intravenous methylprednisolone followed by cyclophosphamide seemed to be most effective. Seventy per cent of the total patient population had abnormal magnetic resonance imaging findings. In our group of 14 patients, those with higher disease activity (measured by the SLAM) at onset of TM were treated more aggressively (for example, with plasmapheresis and intravenous pulse cyclophosphamide). TM in our patients was associated with antiphospholipid antibodies in 43% of the cases as compared with 64% of the total patient population. Optic neuritis occurred in 48% of the total patient population with SLE and TM, suggesting an association.

CONCLUSIONS

TM in SLE is a poorly understood entity. Outcome might be more favourable than previously suggested. There is an association of TM with antiphospholipid antibodies in SLE patients. Treatment including intravenous cyclophosphamide may improve the final outcome. This report emphasises the need for multicentre trials to establish guidelines for optimal treatment.

End-stage renal disease in sarcoidosis of the kidney

We describe two cases of black women with biopsy-proven sarcoidosis of the kidney who developed end-stage renal disease. Treatment with high-dose glucocorticoids resulted in a good initial response, followed by progressive deterioration of renal function requiring hemodialysis.

Immune cell biochemical abnormalities in systemic lupus erythematosus

Novel data have emerged which attempt to characterize the biochemical abnormalities that are exhibited by lupus immune cells. Lupus lymphocytes display abnormal antigen-receptor-mediated signaling, consisting of increased Ca2+ mobilization and increased protein tyrosyl phosphorylation that are independent of disease activity. Abnormalities in the expression and function of co-stimulatory molecules (B7-CD28 and CD40-CD40L) have been established. Transcription of cytokine genes and the methylation of DNA which affects multiple genes are also abnormal. Finally, aberrations of the apoptosis of lupus immune cells are contributors to the pathogenesis of the disease.

Increased expression of functional Fas-ligand in activated T cells from patients with systemic lupus erythematosus

The Fas ligand induces apoptosis upon binding to Fas/APO-1 (CD95) bearing target cells. Activation induced cell death (AICD) in T cells is mediated by upregulation of Fas ligand on the cell surface membrane upon crosslinking of the TCR. AICD is considered to be essential for the elimination of autoreactive T cells in the peripheral blood. To elucidate possible abnormalities in the process of AICD in human SLE, we studied the expression and function of Fas ligand in polyclonal T cell lines from patients with SLE, patients with other rheumatic diseases and normal controls. SLE T cells expressed on their surface significantly higher amounts of Fas ligand compared to the two control groups. Stimulation of the cells with anti-CD3 mAb lead to further increase in surface membrane Fas ligand expression in all three groups with SLE expressing the highest amounts. The percentage of increase was though lower in SLE T cells than in normal T cells or disease control cells. The T cells were examined for Fas ligand-mediated cytotoxicity in a 51Cr release assay using Fas-expressing normal T cells as target cells. There was no difference in SLE and control T cells with regard to specific 51Cr lysis, indicating that the Fas ligand expressed by the SLE T cells is functional. Our data show that activated T cells from patients with SLE express high amounts of functional Fas ligand with intact TCR-mediated upregulation. This could account for the high apoptotic rates that have been observed in lymphocytes from patients with SLE.

Detection of hyperdiploid malignant cells in body cavity effusions by fluoresence in situ hybridization on ThinPrep slides

BACKGROUND

Benign body cavity effusions sometimes cannot be distinguished from malignant ones by conventional cytology. The authors performed fluorescence in situ hybridization (FISH) on ThinPrep slides using chromosome specific probes to see if hyperdiploid malignant cells could be detected in 20 body cavity effusions. The results were then compared with those of conventional cytology.

METHODS

A total of 20 body cavity effusions from 19 patients were studied using conventional cytology and FISH. Probes specific for chromosomes 3, 8, 10, and 12 were used to detect hyperdiploidy on ThinPrep slides (Cytyc Corporation, Boxborough, MA).

RESULTS

A total of 13 patients had malignant conditions (either prior history of malignancy or the presence of malignancy anywhere in the body). Conventional cytology and FISH were both positive in 5 of these patients (6 samples) and negative in 2 patients. The results for one sample were inconclusive by both methods. There were 5 discrepant cytology-FISH results in patients with malignant conditions. One sample was positive by FISH and negative by cytology, one was positive by FISH and "atypical" by cytology, and three were inconclusive by FISH and negative by cytology. FISH results were either negative (in 4 samples) or inconclusive (in 2 samples) in the 6 patients with benign conditions.

CONCLUSIONS

FISH can detect hyperdiploid malignant cells in body cavity effusions and is especially useful when the major cell population consists of malignant cells that cannot be differentiated from mesothelial or "atypical" cells. It is less useful in detecting a small population of malignant cells hidden in an inflammatory or reactive cell background. More studies are needed to establish diagnostic criteria further and to assess the clinical usefulness of this procedure.

Lymphocytes, cytokines, inflammation, and immune trafficking

Studies reported during the past year have added new knowledge to our understanding of the pathogenesis of systemic lupus erythematosus. A study of sibpairs with lupus revealed a strong linkage of a region located at chromosome 1q41-42 that crossed ethnic barriers. B-cell receptor-initiated signaling events, such as tyrosine protein phosphorylation and intracellular calcium concentrations, were found to be increased in patients with lupus in a disease- and clinical activity-independent manner. T cells from patients with lupus express increased amounts of the CD40 ligand, which is functional because it helps B cells to produce anti-DNA antibodies and express more CD80 (B7-1) on their surface. Only occasionally do lupus patients display structural defects of either Fas antigen or ligand molecules, and although spontaneous apoptosis is increased in lupus cells (as well as in other systemic autoimmune disorders), the activation-induced T-cell death is defective.

Persistent expression of a soluble form of Fas/APO1 in continuously activated T cells from a patient with SLE

OBJECTIVE

To report a patient with SLE whose T cells expressed disproportionally increased amounts of an alternatively spliced form of Fas/APO1 transcript and secreted a soluble form of Fas.

METHODS

We established continuously activated, short-term T cell lines from 16 patients with SLE and from 6 normal controls. The structure, expression and function of Fas was examined using RT-PCR and sequencing, flow cytometry (surface expression of Fas), ELISA (measurement of soluble Fas) and a PI-based cytotoxicity assay (functional analysis).

RESULTS

A soluble form of Fas which originates from an alternatively spliced transcript and lacks the transmembrane domain of the original molecule was the dominant product of the Fas-gene in one line (S18B) derived from a patient with very active SLE. Compared to a control line, the S18B cells displayed decreased surface Fas expression but increased accumulation of Fas inside the cell. The amount of soluble Fas in the culture supernatant of S18B was found to be 1.8 times higher than that of a control line. Culture supernatants from S18B cells inhibited anti-Fas mAb-medicated T cell death.

CONCLUSION

Continuously activated T cells from one patient with SLE displayed increased amounts of soluble Fas that inhibits anti-Fas mediated cell death. Although the frequency of this abnormality among patients with SLE and other diseases is unknown, increased production of soluble Fas may have contributed to the pathogenesis of SLE in the patient presented here.

Defective CD3-mediated cell death in activated T cells from patients with systemic lupus erythematosus: role of decreased intracellular TNF-alpha

Activation-induced cell death (AICD) plays an important role in the regulation of the immune response by eliminating preactivated and potentially autoreactive cells. To elucidate possible abnormalities of AICD in human systemic lupus erythematosus (SLE), we studied AICD in activated T cells from patients with SLE and normal controls. CD3-mediated cell death was determined in short-term T cell lines by flow cytometry using propidium iodide staining and analysis of DNA subdiploid peak populations. It was found to be significantly lower in T cells from SLE patients compared to cells from normal controls. Anti-Fas mAb-mediated cell death was similar in SLE and control cell lines. CD3-mediated AICD could be blocked in control and SLE T cell lines by an IgG anti-Fas mAb. Indirect immunofluorescence analysis showed statistically significantly less intracellular TNF-alpha in SLE T cells than in control cells. These data show that activated T cells from patients with SLE are relatively resistant to a TCR-mediated death stimulus although they display intact anti-Fas mAb-mediated cell death. Defective antigen-mediated cell death can contribute to increased numbers of activated autoreactive cells in lupus patients.

B cells from patients with systemic lupus erythematosus display abnormal antigen receptor-mediated early signal transduction events

To understand the molecular mechanisms that are responsible for the B cell overactivity that is observed in patients with SLE, we have conducted experiments in which the surface immunoglobulin (sIg)-mediated early cell signaling events were studied. The anti-sIgM-mediated free intracytoplasmic calcium ([Ca2+]i) responses were significantly higher in SLE B cells compared with responses of normal individuals and to those of patients with other systemic autoimmune rheumatic diseases. The anti-IgD mAb induced [Ca2+]i responses were also higher in lupus B cells than in controls. The magnitude of anti-sIgM-mediated Ca2+ release from intracellular stores was also increased in B cells from SLE patients compared with normal controls. The amount of inositol phosphate metabolites produced upon crosslinking of sIgM was slightly higher in patients with lupus than in normal controls, although the difference was not statistically significant. In contrast, the degree of anti-sIgM-induced protein tyrosine phosphorylation was obviously increased in lupus patients. Our study demonstrates clearly for the first time that SLE B cells exhibit aberrant early signal transduction events, including augmented calcium responses after crosslinking of the B cell receptor and increased antigen-receptor-mediated phosphorylation of protein tyrosine residues. Because the above abnormalities did not correlate with disease activity or treatment status, we propose that they may have pathogenic significance.

Elevated in vivo expression of the costimulatory molecule B7-BB1 (CD80) on antigen presenting cells from a patient with SLE

The CD28/CTLA4-B7-family plays an important role in T-cell costimulation and is crucial for IL-2 production and tolerance induction. The costimulatory molecule B7-BB1 (CD80) is expressed on activated antigen presenting cells, but its expression on peripheral blood mononuclear cells is very low. Here we report a patient with untreated SLE whose peripheral blood antigen presenting cells expressed increased amounts of B7-BB1.

Defective antigen-presenting cell function in patients with systemic lupus erythematosus

OBJECTIVE

Patients with systemic lupus erythematosus (SLE) who exhibit defective in vitro responses to recall antigens and normal responses to alloantigens have been shown to have an abnormality in antigen-presenting cell (APC) function. This study was undertaken to further characterize this defect in APC function in lupus patients.

METHODS

Mononuclear cells (MNC) from the peripheral blood of patients with SLE and from normal individuals were cultured in the presence of either recall antigen tetanus toxoid (TT), anti-CD3 (OKT3) monoclonal antibody, or alloantigens, and proliferative or interleukin-2 responses were assessed. Cell surface expression of B7-1 was assessed by flow cytometry.

RESULTS

MNC from all normal individuals and from 7 patients with SLE responded to both TT and alloantigen and were designated +/+. Twelve SLE patients did not respond to TT but did respond to alloantigen stimulation and were designated -/+. In both normal subjects and SLE patients, the ability to respond to OKT3 correlated strongly with the ability to respond to recall antigen. A defect in APC costimulatory function was suggested by data demonstrating that interferon-gamma-induced expression of B7-1 was significantly reduced in SLE patients compared with controls. Neither controls nor SLE patients expressed detectable amounts of surface B7-1 molecule on resting APC. Defective recall and anti-CD3-stimulated responses could be enhanced in SLE patients in the presence of B7/BBl-transfected P815 murine mastocytoma cells underscoring an SLE-associated defect in costimulatory activity. However, nontransfected P815 cells were also able to enhance responses to OKT3 in -/+ patients; blocking experiments showed that this was mediated through an IgG Fc receptor-dependent mechanism.

CONCLUSION

These data indicate that SLE-associated defects in APC function in vitro can be accounted for by abnormalities in APC surface membrane molecules such as B7, IgG Fc receptors, and possibly others.

Cross-linking of the Fas/APO-1 antigen suppresses the CD3-mediated signal transduction events in human T lymphocytes

The Fas/APO-1 Ag, a member of the TNF-R family, mediates apoptosis (programmed cell death, PCD). PCD has been recognized to be important in the regulation of normal and autoimmune responses. However, the underlying molecular mechanisms are not fully known. To elucidate the role of the Fas Ag in lymphocyte activation, we investigated the influence of Fas Ag cross-linking on CD3/TCR-mediated signal transduction in IL-2-dependent human T cell lines. Early signal transduction events were evaluated in 10-day-old T cell lines using anti-Fas and anti-CD3 mAbs. Incubation of Indo-1-loaded cells with anti-Fas mAb (10 micrograms/ml), but not with an isotypic control mAb almost completely inhibited the anti-CD3-mediated Ca2+ influx. This inhibition was mAb concentration dependent and was detected after incubation for at least 15 min. Cross-linking of the Fas Ag did not affect the anti-CD3-mediated release of Ca2+ from the internal stores or the thapsigargin-mediated Ca2+ influx. Anti-Fas mAb-incubated cells also showed decreased CD3-mediated inositol 1,4,5-trisphosphate production. Preincubation of cells with anti-Fas mAb inhibited the anti-CD3-mediated tyrosine phosphorylation of multiple cellular proteins. Cross-linking of the Fas Ag for up to 6 h did not alter the expression of CD3 on the surface of the T cells. Preincubation of Indo-1-loaded EBV-transformed B cells with anti-Fas mAb did not affect the anti-mu Ab-induced increase in intracellular calcium ([Ca2+]i). Our results show that cross-linking of the Fas Ag can suppress the receptor-mediated signaling process in human T but not B cells.

Cross-linking of the Fas/APO-1 antigen suppresses the CD3-mediated signal transduction events in human T lymphocytes

The Fas/APO-1 Ag, a member of the TNF-R family, mediates apoptosis (programmed cell death, PCD). PCD has been recognized to be important in the regulation of normal and autoimmune responses. However, the underlying molecular mechanisms are not fully known. To elucidate the role of the Fas Ag in lymphocyte activation, we investigated the influence of Fas Ag cross-linking on CD3/TCR-mediated signal transduction in IL-2-dependent human T cell lines. Early signal transduction events were evaluated in 10-day-old T cell lines using anti-Fas and anti-CD3 mAbs. Incubation of Indo-1-loaded cells with anti-Fas mAb (10 micrograms/ml), but not with an isotypic control mAb almost completely inhibited the anti-CD3-mediated Ca2+ influx. This inhibition was mAb concentration dependent and was detected after incubation for at least 15 min. Cross-linking of the Fas Ag did not affect the anti-CD3-mediated release of Ca2+ from the internal stores or the thapsigargin-mediated Ca2+ influx. Anti-Fas mAb-incubated cells also showed decreased CD3-mediated inositol 1,4,5-trisphosphate production. Preincubation of cells with anti-Fas mAb inhibited the anti-CD3-mediated tyrosine phosphorylation of multiple cellular proteins. Cross-linking of the Fas Ag for up to 6 h did not alter the expression of CD3 on the surface of the T cells. Preincubation of Indo-1-loaded EBV-transformed B cells with anti-Fas mAb did not affect the anti-mu Ab-induced increase in intracellular calcium ([Ca2+]i). Our results show that cross-linking of the Fas Ag can suppress the receptor-mediated signaling process in human T but not B cells.

TCR/CD3 complex-mediated signal transduction pathway in T cells and T cell lines from patients with systemic lupus erythematosus

We studied the TCR/CD3 complex-mediated signal transduction pathway in freshly isolated T cells and T cell lines from patients with systemic lupus erythematosus (SLE). The peak and 5-min anti-CD3 mAb-mediated free intracytoplasmic Ca2+ concentration ([Ca2+]i) increase was statistically significant higher in fresh T cells from SLE patients than in control T cells. Increased CD3-mediated [Ca2+]i responses were observed in T cells from patients with SLE but not in T cells from other rheumatic diseases. Furthermore, significantly increased CD3-mediated [Ca2+]i responses were observed in T cell lines from SLE patients but not from controls. Although the [Ca2+]i response did not correlate with the global SLE disease activity or individual clinical manifestations, it was significantly higher in the group of patients who were not on treatment. Both CD4+ and CD8+ T cell subsets from peripheral blood cells and T cell lines displayed higher CD3-mediated [Ca2+]i responses than their normal counterparts. The peak of the response occurred earlier in the patient than in the normal group. The amount of Ca2+ that was released from the intracellular stores was higher in lupus than control T cells. The TCR/CD3-induced production of inositol phosphate metabolites in SLE cells was comparable with controls. The sarcoplasmic and endoplasmic reticulum Ca(2+)-ATPase inhibitor thapsigargin-induced [Ca2+]i response was similar in both SLE and normal T cells. Our experiments demonstrate for the first time a definite abnormality in the early steps of the TCR/CD3-mediated signal transduction pathway in T cells from SLE patients that involves increased release of Ca2+ from intracellular stores.

TCR/CD3 complex-mediated signal transduction pathway in T cells and T cell lines from patients with systemic lupus erythematosus

We studied the TCR/CD3 complex-mediated signal transduction pathway in freshly isolated T cells and T cell lines from patients with systemic lupus erythematosus (SLE). The peak and 5-min anti-CD3 mAb-mediated free intracytoplasmic Ca2+ concentration ([Ca2+]i) increase was statistically significant higher in fresh T cells from SLE patients than in control T cells. Increased CD3-mediated [Ca2+]i responses were observed in T cells from patients with SLE but not in T cells from other rheumatic diseases. Furthermore, significantly increased CD3-mediated [Ca2+]i responses were observed in T cell lines from SLE patients but not from controls. Although the [Ca2+]i response did not correlate with the global SLE disease activity or individual clinical manifestations, it was significantly higher in the group of patients who were not on treatment. Both CD4+ and CD8+ T cell subsets from peripheral blood cells and T cell lines displayed higher CD3-mediated [Ca2+]i responses than their normal counterparts. The peak of the response occurred earlier in the patient than in the normal group. The amount of Ca2+ that was released from the intracellular stores was higher in lupus than control T cells. The TCR/CD3-induced production of inositol phosphate metabolites in SLE cells was comparable with controls. The sarcoplasmic and endoplasmic reticulum Ca(2+)-ATPase inhibitor thapsigargin-induced [Ca2+]i response was similar in both SLE and normal T cells. Our experiments demonstrate for the first time a definite abnormality in the early steps of the TCR/CD3-mediated signal transduction pathway in T cells from SLE patients that involves increased release of Ca2+ from intracellular stores.

Extracorporeal circulation: in vivo and in vitro analysis of complement activation by heparin-bonded surfaces

Complement activation was analyzed during extracorporeal CO2 removal to compare heparin-coated with standard surfaces where systemic heparinization was required. In vivo studies were performed in adult sheep for up to 5 days under standardized conditions using a capillary membrane oxygenator. Applying assays for hemolytic complement function (CH50, APH50) and C3-derived split products, we found that complement activation was markedly reduced in sheep connected to an extracorporeal circuit where heparin was covalently bound by end-point attachment. In addition, incubation of human serum in a miniaturized circulation system revealed less complement activation by heparin-bonded surfaces, as evaluated by enzyme-linked immunosorbent assays for C3a and the activation-specific protein-protein complexes, C1rsC1 inhibitor (classical pathway) and C3b(Bb)P (alternative pathway). Our results provide further evidence that biocompatibility can be improved by end-point attachment of heparin to the surfaces of the extracorporeal circuit.

[Importance of diagnosis in facial pain]

The diagnosis and treatment of facial pain remains a great challenge for oral and maxillofacial surgeons. By taking an exact anamnesis--especially a pain anamnesis--and by starting specific examinations the patient can quickly be recommended to a qualified therapist. The pain syndromes are classified according to the IASP (International Association for the Study of Pain). The pain syndromes the maxillofacial surgeon is most frequently confronted with--idiopathic trigeminal neuralgia, atypical facial pain and the temporomandibular joint--are described. The necessity of a multidisciplinary examination is emphasized and the different diagnostic investigations are illustrated, particularly in the case of myo-arthropathy. Beside the analysis of temporomandibular joint dysfunction, a radiologic examination is performed. In some cases the advise of a neurologist, ophthalmologist or otolaryngologist may be indicated.

[Complications of orbito-frontobasal fractures]

Complications of fronto-basal trauma can, as a function of their severity, be divided into three classes: life-threatening situations, functional complications and cosmetic defects or facial deformities. They find their origin in the type of trauma, the extent of the lesions of bone and soft tissues, as well as in their timely management and quality of treatment. The etiology of the most common complications and their significance are covered with accent on inadequate primary treatment, insufficient repair of dural lesions, inadequate drainage, unstable osteosynthesis, insufficient treatment of scalp- and frontal defects, and finally the lack of antibiotic prophylaxis. The major complications of frontobasal trauma such as chronic cerebral spinal fluid fistulae and pneumocephalus are reviewed. Attention is also given to the importance of adequate drainage in cases of chronic ethmoidofrontal sinusitis, and on the treatment of osteomyelitis and sinus cysts. The therapeutic possibilities in patients with tissue deficits, i.e. reconstruction of frontal skull defects using autologous hip and rib material, as well as split calvarial bone grafts is discussed.

[Peri-orbital surgical approaches]

After having made a definitive diagnosis in patients with orbito-frontal pathology, the choice of incision is an important factor to achieve good intra-operative exposure of the region, as well as to obtain a good functional and aesthetic result. In the majority of cases we prefer to utilize the incisions commonly used for blepharoplasty, especially the transconjunctival approach popularized by Tessier. Other more classic accesses such as the superolateral, infra-orbital and intra-oral incisions, are reserved for treatment of cases of orbitomalar (communition) fractures. We feel there are limited indications for use of incisions through the eyebrows with medial extensions for exposure of isolated lesions of the medial orbital wall, orbital roof, and the anterior wall of the frontal sinus. However they may become very useful as the primary incisions in the treatment of open fractures of the orbital region. The bicoronal incision, a classical approach in neurosurgery, is also being used by us in cases of tumors and complicated middle face fractures which appear to extend to the orbito-frontobasal region in 40% of our patients. In addition it provides excellent access for post-traumatic reconstruction of orbito-frontal bone defects and impacted fractures. A combination of different incisions: bicoronal, peri-orbital and intra-oral, may be indicated for the correction of syndromal anomalies such as Treacher-Collins, for treatment of complicated facial fractures, or for pure aesthetic surgery procedures, such as the "mask-lift" introduced by Tessier.

[Pedicled facial bone flap for closure of the approach in Caldwell-Luc type sinus operations. Its role in the prevention of postoperative complications]

The primary or secondary reconstruction of the facial access after Caldwell-Luc and the more selective resection of sinusal mucous membranes can be important in the therapy and prevention of postoperative complications such as neuralgic facial pain, formation of cysts and chronic sinusitis. The different osteoplastic sinus operations are described and the use of a pedicled bonelid is illustrated. The most common accepted ethiology of post-operative pain is based on the formation of scar-tissue. Postoperative pain is first being treated conservatively, while in case of persisting pain an exploration with dissection of the infra-orbital nerve and reconstruction of the facial defect can be indicated. In a retrospective study of 36 patients the results of our surgical therapy are illustrated.

[Treatment concept of facial pain]

The therapy of chronic facial pain still poses an important challenge. A therapeutical scheme in four steps has been developed. This scheme enables modification of the pain therapy depending on localisation, intensity and former treatment. It consists of the following steps: 1. Transcutaneous electrical nerve stimulation. 2. Medication 3. Extracranial glycerol blocking of the trigeminal nerve 4. Neurosurgical treatment with thermocoagulation, chemical glycerol-rhizotomy and microsurgical decompression. The different therapeutical steps have no influence on each other.

Submental liposuction in maxillo-facial surgery

Liposuction is a relatively recent surgical technique used in body contouring plastic surgery to correct fatty dysharmonies. It is of particular interest to the maxillo-facial surgeon to treat submental fat excess. This relatively easy technique is described, using a few clinical examples. Indications in maxillo-facial surgery are the correction of "double chin" deformity and increased submental fullness after orthognathic surgical procedures as mandibular setback, as well as an adjunct to rhytidectomy.

Heparin-coated versus non-coated surfaces for extracorporeal circulation

Studies were made to compare completely heparin-bonded (HBS) and conventional extracorporeal circulation surfaces using capillary membrane oxygenators (CMO) in sheep and dogs for up to five days. The aims were: to investigate the need for systemic heparinization in the case of heparin-coated surfaces, to assess blood compatibility and gas exchange performance of both systems and the extent of complement activation, and to find solutions for plasma leakage by the use of CMO. All studies were performed under standardized conditions, such as drugs, surgery, priming, blood flow rate etc. For heparin-coated surface studies all blood interfaces (CMO, catheters, tubes, etc) were coated. It was possible to eliminate systemic heparinization totally when HBS were used. During the five-day non-heparin application period blood coagulation parameters were almost unchanged and in the physiological range, platelets did not drop below 80%, hemolysis was negligible and gas exchange performance was unaffected. Less complement activation occurred with HBS than with non-coated surfaces.