Modern technologies for radiofrequency pulmonary vein isolation. Comparison of radiofrequency balloon catheter with high power-short duration ablation in patients with paroxysmal atrial fibrillation

Funding Acknowledgements

Type of funding sources: None.

Background

Pulmonary vein isolation (PVI) is an established therapy for symptomatic atrial fibrillation (AF). Traditional point by point ablation can be time consuming requiring advanced training. Novel radiofrequency (RF) ablation techniques sought to facilitate PVI. Point by point ablation using high power short duration (HPSD) settings has already shown to be safe and effective whereas there is paucity of data using a novel multi-electrode balloon catheter (Heliostar™, Biosense Webster, CA, USA).

Purpose

We aimed to assess procedure characteristics, efficacy, and safety of the Heliostar™ RF-balloon catheter in direct comparison with the latest RF ablation technique.

Methods

All patients undergoing PVI using the Heliostar™ between September and November 2021 were included in this ongoing single center registry. Procedural data and outcome were assessed and compared with data from patients undergoing initial PVI for paroxysmal AF with the HPSD approach from our specifically designed database. A power setting of 70W/7s (70W/5s at posterior wall) was considered as HPSD.

Results

A total of 51 consecutive patients (61±16 years, 49% male) were included. Of those 13 patients undergoing RF-balloon and 38 patients HPSD ablation. Baseline parameters did not differ between groups. Acute PVI was achieved in all patients. For every RF-application with the RF-balloon all necessary criteria were met: Inflation index was between 0.9 and 1.0 and a minimum of 9/10 electrodes were within impedance range. A mean of 2.8±1.4 applications per vein (LSPV 3.2±2.9, LIPV 2.6±2.5, RSPV 2.8±2.0 and RIPV 1.8±0.8) were necessary to achieve durable isolation. The mean maximum esophageal temperature was 40.2±0.8°C. When comparing procedural parameters with HPSD no statistically significant difference was seen regarding procedure duration (Heliostar™ 111±28min and HPSD 100±25min; p=0.3) and left atrial dwell time (Heliostar™ 90±23min and HPSD 80±26min; p=0.08). Fluoroscopy time (Heliostar™ 17±4min and HPSD 13±5min; p=0.005) and dose (Heliostar™ 3961±1325mGy*cm2 vs. HPSD 3153±1833mGy*cm2; p=0.04) were higher in the Heliostar™ group. No major complication occurred in both groups. A three month follow up was available for 10 patients in the Heliostar™ and for 38 patients in the HPSD group. All 10 Heliostar™ patients and 79% of the HPSD patients were free from atrial arrhythmias at follow up.

Conclusion

The novel multi-electrode RF-balloon has shown to be safe and effective in the first clinical routine AF ablation procedures. The tendency towards longer LA dwell times, procedure durations and the significantly higher fluoroscopy exposition in comparison with the HPSD PVI can be attributed to the learning curve applying a new ablation system. More experience is needed in the future to determine the benefits of the novel RF-balloon.

Procedural and outcome impact of obesity in cryoballoon versus radiofrequency pulmonary vein isolation in atrial fibrillation patients

Funding Acknowledgements

Type of funding sources: None.

Background

Cryoballoon-(CB)- and radiofrequency-(RF)-ablation are the most common techniques for pulmonary vein isolation (PVI) in patients (pts) with symptomatic atrial fibrillation (AF). An increasing number of pts undergoing PVI are obese.

Objective

To address the paucity of procedural differences and outcome data of CB- vs. RF-based PVI in relation to body mass index (BMI) of AF patients.

Methods

All pts undergoing de novo PVI between 01/2018-08/2019 at our university hospital were included in this retrospective analysis. Pts of each group (CB-PVI vs. RF-PVI) were subdivided based on their BMI: normal weight BMI <25kg/m², pre-obesity 25-30kg/m², obesity stage I 30-35kg/m² and severe obesity stage II ≥35kg/m². Hereafter, procedural characteristics and AF recurrence rate during follow-up were compared with regard the different BMI groups.

Results

A total of 526 pts (62% male, 65.3±11.2 years) underwent successful de novo PVI (320 CB and 206 RF). Especially in obese patients, differences in procedural characteristics were noted: A significantly increased contrast medium volume in CB group (all: CB 50 [40-80] vs. RF 20 [20-30], p<0.001; BMI≥35: CB 70 [54.5-102.5] ml vs. RF 20 [15-30] ml, p<0.001). In line with previous studies, the overall procedure time was significantly shorter with CB-PVI (CB 75 [60-100] vs. RF 120 [110-180], p<0.001). Also, as expected, lower fluoroscopy dose was detected in RF group (all: CB 392.4 [197.9-995.9] vs. RF 282.5 [139.8-507.2], p<0.001). The complication rate was equal throughout all BMI groups.

A 12-month follow up was available in 480 of 526 (91%) pts. Freedom from any arrhythmia was comparable between CB-PVI and RF-PVI (CB 77% vs. RF 75%, p=0.63). However, for obese pts a trend towards higher AF recurrence rate after RF- compared to CB-PVI was observed (BMI≥35: CB 24% vs. RF 50%, p=0.099).

Conclusion

For obese pts CB-PVI is similarly safe and effective as RF-PVI. The significantly shorter procedure time for CB-PVI may minimize potential obesity-related complications. However, the lower contrast medium quantity and fluoroscopy dose in RF-PVI must be considered. AF recurrence rates were comparable between CB-PVI und RF-PVI. Randomised trials are needed to evaluate the long-term freedom of AF recurrence in pts with higher BMI comparing CB- vs. RF-based PVI and possible obesity related complication.

Validation of seven risk scores in a prospective and independent cohort: the challenge of predicting recurrence after atrial fibrillation ablation

Funding Acknowledgements

Type of funding sources: None.

Background

Several predictive scores for atrial fibrillation (AF) recurrence after ablation have been developed, only some of these are validated in prospective cohorts. The predictive value of such scores has thus far been limited, and many have not been compared with one another.

Aims

We sought to compare the predictive value of seven previously described risk scores ((CHA2DS2 and CHA2DS2-VASC, HATCH, APPLE, CAAP-AF, BASE-AF2, MB-LATER) for prediction of AF recurrence risk at 12 months after AF ablation. Further, we aimed to identify additional variables to predict recurrences after AF ablation.

Methods

We analyzed data from of our prospective digital AF ablation registry to compare the previously published scores in an independent and prospective cohort (n=883, 50.8% with paroxysmal AF). Patients were undergoing de-novo ablation of AF received a pulmonary vein isolation (PVI) using radiofrequency (RF) ablation or cryoablation. Ablation procedures for recurrences of AF after initial PVI included re-isolation of the pulmonary veins by RF ablation, with additional substrate modification at the operators’ discretion.

Early recurrence and recurrence after ablation were defined as any AF or atrial tachycardia episode lasting ≥ 30 s in the first 3 months after ablation and from the end of the 3-month period to 12 months after ablation. Follow-up of patients was scheduled at regular intervals 3 and 12 months after ablation, and included Holter-ECG, 12-lead ECG and history. Outcome-relevant data from implanted cardiac devices (CIED), such as 2-chamber ICD and pacemakers, or implantable loop recorders were analyzed when available.

A predefined subgroup analysis was performed in the following subgroups: first procedure vs. redo procedure, paroxysmal vs. persistent AF, and RF ablation vs. cryoablation.

Results

The BASE-AF2 (AUC 0.630, p<0.001), MB-LATER (AUC 0.612, p<0.001) CAAP-AF (AUC 0.591, p<0.001), APPLE (AUC 0.591, p<0.001) and CHA2DS2-VASC (AUC 0.547, p=0.018) scores had a significant but modest predictive value for 12-month AF-recurrence. None of these scores was significantly superior. Other previously published scores had no predictive value. There was no difference in the predictive value for 12-month recurrence of AF between first procedure vs. redo procedure and RF ablation vs. cryoablation. Unlike other scores, MB-LATER showed better predictive value for paroxysmal vs. persistent AF (AUC 0.632 vs. 0.551, p=0.038). In the multivariate logistic regression, only age (p=0.006), number of prior electrical cardioversions (p<0.001) and early AF recurrence (p<0.001) were independent predictors of 12-month AF recurrence.

Conclusion

Despite numerous available scores, predicting recurrences after AF ablation remains challenging. New simple and robust predictors are needed, potentially based on diagnostic interventions, as well as novel genetic, functional and anatomic parameters.

Impact of pacing output and cycle length on qrs morphology in ablation of premature ventricular contractions (PACE-MAP-Trial)

Funding Acknowledgements

Type of funding sources: None.

Background

Pace mapping is an established technique to localize the origin of premature ventricular contractions (PVC). The QRS morphology induced by endocardial pacing is compared with a previously recorded template of the target arrhythmia. Based upon historic in-vitro models pacing at the arrhythmia’s coupling interval (CI) and stimulation threshold has become the gold standard in pace mapping.

Purpose

There is a paucity of data supporting pacing at the CI and stimulation threshold as the gold standard for pace mapping. In this prospective study, we sought to assess systematically the impact of variations of pacing output and cycle length on the resulting QRS morphology during pace mapping in the context of PVC ablation (NCT05061498).

Methods

All patients undergoing ablation of idiopathic PVC were prospectively enrolled in this study. Pace mapping was performed using four different parameter settings: (1) A predefined fixed burst at maximum output (10V/2ms), (2) fixed burst at stimulation threshold, (3) coupling interval at maximum output and (4) coupling interval at stimulation threshold. Pacing cycle length (PCL) of the fixed burst was defined as follows: for a CI ≤450ms = PCL of CI+100ms and for a CI ≥450 = PCL of CI-100ms. Using an automated waveform comparison algorithm, the resulting QRS complexes were matched with the clinical PVC, and with the gold standard. For every parameter setting the mean of the matching percentage of three QRS complexes entered the analysis.

Results

We report data of the first 22 consecutive patients (53±15 years, 64% female) enrolled in this ongoing study between May and November 2021. The pacing protocols were performed at 39 different sites: 5/39 epicardially via great cardiac vein, 15/39 in the RVOT 12/39 and 7/22 in the left ventricular cavity. When comparing the QRS morphologies resulting from the four different pace mapping settings with the clinical PVC, the univariate analysis revealed no difference between groups (p=0.9). Furthermore, there was no difference comparing the paced QRS morphologies at different output and cycle length to the gold standard of threshold pacing at coupling interval (p=0.9).

Conclusion

Variations of pacing output and stimulation cycle length during pace mapping does not affect QRS morphology during PVC ablation. Applying a modern automated waveform comparison tool, no advantage was observed when comparing with the gold standard. It is therefore reasonable to assume, that pace mapping can be performed using an easily applicable setting of a fixed burst at maximum pacing output.

[Systemic mast cell disease with gastrointestinal symptoms--a diagnostic questionnaire]

Systemic mast cell disease often becomes clinically manifest as a mast cell mediator activation syndrome with episodic or chronic nonspecific abdominal symptoms. As a result of genetic alterations, pathological mast cells have an increased proliferation rate as well as accumulation within different organs with consequential effect on gastrointestinal secretion, absorption, pain perception and motility caused by release of their mediators. These changes may not be detected in routine laboratory or imaging methods. This report describes how the diagnosis systemic mast cell disease can be established with a diagnostic questionnaire based on a synopsis of clinical findings relevant to a mast cell mediator activation syndrome.

The congenital duplication cyst: a rare differential diagnosis of retrosternal pain and dysphagia in a young patient

Congenital cysts are malformations developing from the endoderm and mesoderm of the digestive and respiratory system in the early weeks of gestation. Unilocular or multilocular dysontogenic cysts are most commonly thoracically located adjacent to the trachea and bronchus and the development of an oesophageal duplication cyst in the oesophageal wall is extremely rare. The duplication cyst in the adult is usually asymptomatic and an incidental diagnosis. Potential symptoms include dysphagia and retrosternal pain. Next to endoscopy and computer tomography, endoscopic ultrasonography is mandatory for a distinguished and accurate preoperative evaluation. Transthoracic excision is crucial for definitive diagnosis and inhibition of complications.

Enteric dysfunction in patients with asymptomatic HIV-infection versus patients with hypoproteinemia/hypalbuminemia and advanced HIV-infection

BACKGROUND

It is unclear whether enteric dysfunction and protein losses contribute to hypoproteinemia, which heralds poor survival in HIV infection.

METHODS

We investigated alpha-1-antitrypsin-clearance (AAT-CL), D-xylose resorption and total gut transition time in 14 HIV+ patients with hypoproteinemia (serum protein < 6 g/dl, albumin < 3 g/dl, median CD4-cell count 58/microl; (group I)), in 10 asymptomatic HIV+ patients (median CD4-cell count 290/microl, (group II)) and in 15 healthy volunteers (group III).

RESULTS

AAT-CL in group I (16.5 (2.9 278.2) ml/d; median (range)) was higher than in groups II (9.5 (1.7 23.1) ml/d) and III (10.6 (0.8 19.5) ml/d; p = 0.0114). Likewise, D-xylose recovery was on average threefold lower in group I than in groups II (p = 0.0009) and III ( p < 0.0001), whereas total gut transition time was significantly shorter in both HIV-infected groups (group I: 49.8 h (23.5-72.7), p=0.0431; group II: 32.6 h (23-54.6), p=0.0104) than in the healthy controls (group III 61.6 h (39.1-87.7)).

CONCLUSIONS

Thus, impaired intestinal resorption and enteral protein losses may contribute to hypoproteinemia in advanced HIV infection, whereas accelerated intestinal motility may be present already in asymptomatic stages of HIV infection.

Three-dimensional magnetic resonance cholangiopancreatography with respiratory triggering in the diagnosis of primary sclerosing cholangitis: comparison with endoscopic retrograde cholangiography

BACKGROUND AND STUDY AIMS

The purpose of this study was to evaluate the accuracy of respiratory-triggered three-dimensional magnetic resonance cholangiopancreatography (3D-MRCP) for the detection of primary sclerosing cholangitis (PSC) and to compare the specific findings of magnetic resonance cholangiography and endoscopic retrograde cholangiography in patients with PSC.

PATIENTS AND METHODS

The MRCP findings were evaluated in 150 patients with clinical symptoms (progressive fatigue, pruritus followed by icterus) and/or elevated values for alkaline phosphatase and serum aspartate transaminase, and occasionally an elevated serum concentration of bilirubin as a sign of cholestasis, who were consecutively referred for magnetic resonance imaging. Two observers independently classified bile duct abnormalities and established the MRCP diagnosis in a consensus reading. The results of MRCP were compared with the definitive diagnosis, which was based on the clinical history and laboratory and histological data, as well as on endoscopic retrograde cholangio-pancreatography (ERCP) findings. In a second step, the observers compared the delineation of the biliary system and morphological findings using MRCP and ERCP in patients with confirmed PSC.

RESULTS

Diagnostic examinations were obtained in 146 of the 150 MRCPs (97 %). The diagnosis of PSC was confirmed by clinical data and ERCP in 34 of these 150 patients (23 %). The sensitivity and specificity of MRCP for diagnosing PSC were 88 % (29 of 33) and 99 % (108 of 109), respectively. MRCP and ERCP yielded similar scores for the delineation of the biliary system (P = 0.2) in patients with PSC. However, different bile duct abnormalities leading to the diagnosis of PSC were depicted by MRCP and ERCP; more bile duct stenoses and pruning were seen with ERCP and more skip dilatation with MRCP (P < 10(-4)).

CONCLUSION

In patients with PSC, MRCP is a highly sensitive method and its diagnostic accuracy is comparable to that of ERCP.

Long-term results and prognostic factors in the treatment of achalasia with botulinum toxin

BACKGROUND AND STUDY AIMS

Endoscopic therapy of achalasia by injection of botulinum toxin into the lower esophageal sphincter has very limited adverse effects and is initially successful in 70 % of patients. However, this result only lasts for 6 - 9 months on average in most patients and only half of them benefit for more than 1 year. The aim of this study was to find out which factors are predictive for a good long-term success.

PATIENTS AND METHODS

We retrospectively studied 25 patients with achalasia. The diagnosis had been proven by barium swallow and esophageal manometry. Therapy was carried out endoscopically between June 1996 and December 1998 by injection of 25 mouse units (MU) botulinum toxin into each of the four quadrants of the lower esophageal sphincter (LES). Lower esophageal sphincter pressure (LESP) was measured prior to and 1 week after endoscopic therapy. A standardized questionnaire was used for symptom assessment, at the initial presentation, at 1 week and at 2.5 +/- 0.8 years after treatment.

RESULTS

The LESP was significantly reduced (pre-treatment 62.1 +/- 15.2 mmHg vs. post-treatment 43.1 +/- 12.5 mmHg; P < 0.01). Symptoms improved in 16 patients (pre-treatment symptom score 9.5 +/- 2.9 vs. post-treatment symptom score 4.7 +/- 1.8; P < 0.01). Nine patients showed no relevant improvement. From the 16 patients with a good initial response, two were lost to follow-up. In nine patients the outcome was still satisfactory after a mean of 2.5 years (1.5 - 4 years) (pre-treatment symptom score 9.5 +/- 2.9 vs. symptom score at 2.5 years after Botox 5.1 +/- 1.5; P < 0.05). These patients were on average 67.7 +/- 12.5 years old. The remaining five patients received a second or third injection of botulinum toxin, but none improved substantially for more than 6 months. One of them eventually underwent pneumatic dilation, and three laparoscopic myotomy. Thus, botulinum toxin treatment was unsuccessful in 14 patients in all. These 14 patients were, on average, significantly younger than the nine successfully treated patients (46.1 +/- 12.6 years vs. 67.7 +/- 12.5 years; P < 0.01) and had significantly higher LESP values prior to botulinum toxin therapy (72.8 +/- 8.9 mmHg vs. 47.8 +/- 9.2 mmHg; P < 0.01).

CONCLUSIONS

The long-term success of botulinum toxin injection into the LES in patients with achalasia is highest in elderly patients and in patients with an LESP not exceeding the upper normal level prior to treatment by 50 % or more. On the basis of our results, younger patients (< 55 years) with a severe increase in LESP do not seem to benefit from botulinum toxin injection and pneumatic dilation or myotomy may be more advantageous to them.

Decreased prevalence of Helicobacter pylori infection in HIV patients with AIDS defining diseases

Various clinical studies indicated a lower prevalence of HP infection in HIV patients. The present study was initiated to determine whether the decreased frequency of HP infections in HIV patients might be associated with the stage of the underlying HIV disease or concomitant drug regimens the patients had received. 60 randomly selected HIV outpatients were stratified according to the stage of their HIV infection (CDC classification), their CD4 cell count and to the drug regimens they were given. Within these subgroups of patients, HP infection prevalence was separately investigated by serological and C13 breath testing. Data were compared to a reference population of 30 healthy volunteers. No difference in HP infection prevalence was found between the HIV infected patients in general and the reference cohort. A significantly lower proportion of HP infected individuals was observed among those HIV patients who had AIDS-defining diseases. Furthermore, a substantial but insignificant decrease of HP infection prevalence was noted in HIV patients with an extensive decline of CD4 cell count (< 100/microl). HIV patients who had received antimicrobial or H2-antagonizing drugs within 12 months prior to the study commencement also were found to have a remarkably decreased frequency of HP infections independently of their CD4 cell count. No association between HP infection prevalence and patients age, sex, risk group and the type of their antiretroviral treatment was found.We concluded from these results that the decreased HP infection prevalence in HIV patients may, apart from frequent antibiotic treatment, be correlated to the stage of HIV-mediated immune suppression.

Effect of short-term topical corticosteroid treatment on mucosal enzyme systems in patients with distal inflammatory bowel disease

BACKGROUND/AIMS

Glucocorticoids, even when administered topically, have a known early benefit on diarrheal symptoms in inflammatory bowel diseases which may not be explained exclusively by their anti-inflammatory effect. Therefore, we evaluated a possible early effect of topically administered glucocorticosteroids on the mucosal function of patients with distal inflammatory bowel disease in a prospective, controlled study, which was blinded for histological evaluation.

METHODOLOGY

Eleven patients with distal ulcerative colitis or Crohn's disease, and 8 patients without intestinal inflammation were studied. A sigmoidoscopy with biopsy sampling (8-10) was performed before and 3 days after rectal administration of a hydrocortisone acetate foam preparation (100 mg b.i.d.). Prior to and after topical steroid treatment, basolateral (Na++K+)-ATPase activity (coupled optical assay), specific 3H ouabain binding (rapid filtration method), 5'-nucleotidase (microdetection method of phosphorus), and mucosal DNA levels (diphenylamine reaction) were determined from biopsy homogenates. Morphological and clinical characteristics were assessed according to established scores.

RESULTS

Short-term topical GCS treatment significantly (p<0.05) stimulated (Na++K+)-ATPase activity (103%) as well as the number of active (Na++K+)-ATPase molecules (190%). In the healthy mucosa, only (Na++K+)-ATPase activity was stimulated (124%, p<0.05; specific 3H ouabain binding: 33%; p=0.09). As an unspecific GCS effect, apical 5'-nucleotidase was also stimulated (p<0.05; IBD: 50%; controls: 200%). As assessed by endoscopic and histological scores, as well as by mucosal DNA levels, morphological signs of intestinal inflammation remained unchanged during the study, whereas the daily stool frequency decreased significantly (p<0.05).

CONCLUSIONS

In patients with distal inflammatory bowel disease, short-term treatment with topical GCS leads to a quick recovery from diarrheal symptoms, due to the early improvement of mucosal function prior to the occurrence of the well-known anti-inflammatory GCS effect.

Endoscopic manometry of esophageal varices: evaluation of a balloon technique compared with direct portal pressure measurement

BACKGROUND/AIMS

Recently, a non-invasive endoscopic balloon technique for esophageal manometry was published. In the present study, we assess its methodological aspects together with the relationship to portal pressure.

METHODS

In 20 patients with liver cirrhosis who had received an intrahepatic portosystemic stent-shunt (TIPS), we evaluated portal and variceal pressure before and after balloon occlusion of TIPS (random order). Portal pressure was measured continuously via a portal venous catheter, and variceal pressure was determined at the same time independently by two endoscopists using two balloon techniques (inflation until varix collapses; deflation until varix reappears).

RESULTS

Overall, mean (+/-SD) portal pressure (28.5+/-7 mmHg) was significantly higher (p<0.001) than mean variceal pressure (24.4+/-6 mmHg). Balloon manometry-determined variceal pressure values were 10+/-15% higher with the inflation technique (26.2+/-7 mmHg) than with the balloon deflation technique (22.6+/-6 mmHg, p<0.001). Portal pressure and variceal pressure correlated significantly (p<0.001; balloon inflation: r=0.61, balloon deflation: r=0.66, mean values of inflation and deflation: r=0.68). Short-term TIPS occlusion led to mean increases of 52% and 35% in portal pressure and variceal pressure, respectively. The manometry results of both endoscopists correlated well with either balloon technique (r> or =0.93; p<0.001) and we saw no adverse effects.

CONCLUSIONS

Variceal balloon manometry provides non-invasive variceal pressure data which correlate to portal pressure assessed prior to and after short-term TIPS occlusion. However, probably due to variance in collateral anatomy, variceal pressure does not exactly predict portal pressure and its acute changes in the individual patient. The averaged variceal pressure of the inflation and deflation balloon technique provides the best relation to portal pressure combined with a good interobserver reliability and warrants further clinical evaluation.

Noninvasive endoscopic determination of intravariceal pressure in patients with portal hypertension: clinical experience with a new balloon technique

BACKGROUND AND STUDY AIMS

Recently, details of a noninvasive balloon manometry technique for endoscopic measurement of variceal pressure (VP) have been published. However, to date, only few data exist on its feasibility and virtually none on its relation to endoscopic or clinical variables of portal hypertension.

PATIENTS AND METHODS

We investigated a total of 64 patients with esophageal varices using a scaled transparent balloon and a calibrated pressure manometer. Averaged from both fivefold balloon insufflation (variceal collapse) or desufflation (variceal appearance), we took measurements of the VP (mmHg) using the two techniques. These measurements were correlated between two investigators as well as to both clinical and endoscopic signs of portal hypertension. Furthermore, pressures were assessed prospectively before and during propranolol application.

RESULTS

Measurements were successful in > 95% of all sessions without side effects. The intraobserver variance was 11.0 +/- 13.1%. Measurements correlated significantly between two observers (r = 0.80, insufflation technique, p < 0.01/r = 0.81, desufflation technique, p < 0.01). Pressures correlated positively to variceal sizes (p < 0.05). The presence of fundic varices was strongly associated with higher pressures (p < 0.02). In patients without medical decompressive therapy we found a significant relationship between VP and the presence of red colour signs or previous bleeding episodes. Clinical parameters did not correlate with VP (p > 0.05). As assessed by this technique, 8/11 patients receiving propranolol showed a decrease in VP (18.6 +/- 19.5% after 1.5 months and 33.3 +/- 11.9% after 3 months).

CONCLUSIONS

This noninvasive balloon technique is a safe and practical method for estimating VP in patients with portal hypertension. As found by invasive methods, patients with large varices and concomitant fundic varices have higher VP. A drop in intravariceal pressure after propranolol therapy appears to be assessable.

Treatment of Barrett's esophagus by endoscopic argon plasma coagulation

Barrett's esophagus is a premalignant condition characterized by the presence of specialized columnar epithelium in the distal esophagus. Conventional medical or surgical treatments do not consistently lead to a regression of Barrett's epithelium. However, restoration of squamous mucosa can occur in an anacid environment after endoscopic ablation of metaplastic epithelium. We report here on two patients with long-standing history of Barrett's esophagus who were treated with endoscopic argon plasma coagulation. By six months of endoscopic treatment, Barrett's epithelium had regressed by more than 50%, being replaced by apparently normal squamous epithelium in both patients. Extensive histological sampling confirmed the presence of squamous epithelium indistinguishable from normal esophageal mucosa. Both patients were asymptomatic under concomitant therapy with proton pump inhibitors with the exception of slight retrosternal discomfort the day after treatment. This demonstrates that endoscopic argon plasma coagulation may be considered for the treatment of Barrett's esophagus.

[Determination of the count rate for quality control of combined lung ventilation and perfusion scintigraphy: case report]

We present the case of a 43-year-old male patient who suffered from a massive pulmonary embolism, induced by a peritoneovenous shunt of the Denver type. Calculation of the count rates of the ventilation and perfusion scintigraphy respectively showed a too low ventilation/perfusion ratio. After reinjection of additional 99mTc-MAA the second perfusion study showed further mismatch areals. Count rate ratio determination is essential as a clinical quality control.

Cholestasis associated with mesalazine therapy in a patient with Crohn's disease

BACKGROUND/AIMS

Mesalazine is a widely prescribed medication, developed as an alternative to sulfasalazine in the treatment of inflammatory bowel disease. In contrast to sulfasalazine, there are only a few case reports on its causing hepatic injury. We here report on a patient with cholestasis after mesalazine therapy for Crohn's disease of the ileum.

METHODS/RESULTS

The patient, a 30-year-old man, developed clinical signs of severe hepatic injury 4 months after treatment with mesalazine (4 g/day) including biopsy-proven hepatocellular cholestasis with minimal focal mononuclear inflammatory infiltration. Contrary to previous reports, no symptoms of generalized hypersensitivity were seen. The patient's illness was resolved by discontinuing the mesalazine treatment and he recovered completely in 40 days.

CONCLUSIONS

This case reinforces the possibility of a causal relationship between mesalazine treatment and toxic hepatic injury without systemic hypersensitivity.

Omega-3 fatty acids and low carbohydrate diet for maintenance of remission in Crohn's disease. A randomized controlled multicenter trial. Study Group Members (German Crohn's Disease Study Group)

BACKGROUND

There is no established therapy for maintaining remission in patients with Crohn's disease. Following different suggestions from the literature, two potential interventions for maintaining remission were tested against placebo, using either 5 g/day of a highly concentrated omega-3 fatty acid compound or a carbohydrate-reduced diet (84 g/day).

METHODS

A total of 204 patients were recruited after they had had an acute relapse. After remission (CDAI < or = 150) was attained with steroid therapy, patients were randomized to receive either omega-3 fatty acids (n = 70), placebo (n = 65), or diet (n = 69). Low-dose prednisolone was given to all patients for the first 8 weeks of intervention. CDAI and an acute-phase protein (CRP) were used as criteria for a relapse.

RESULTS

The proportion of patients without relapse within a year were similar in the placebo and active treatment group (intention-to-treat analysis: placebo, 30%; active treatment, 30%; protocol-adhering patients, 29% versus 28%). Patients did gain benefit (53%; p = 0.023) for as long as they maintained the diet. However, intention-to-treat analysis (diet group, 40%) did not show a noticeable difference when compared with placebo.

CONCLUSIONS

Omega-3 fatty acids did not show an effect on extending the remission in Crohn's disease. For the diet patients the question remains whether the noncompliant patients dropped out early because they sensed a relapse approaching or whether their condition deteriorated because they failed to comply with the diet.

Double-blind dose-finding study of olsalazine versus sulphasalazine as maintenance therapy for ulcerative colitis

OBJECTIVE

To determine the therapeutic efficacy and safety of three doses of olsalazine compared with the standard dose of sulphasalazine.

DESIGN

Randomized double-blind multicentre 6-month study comparing three doses of olsalazine (0.5, 1.25 and 2.0 g daily) and sulphasalazine 2.0 g daily for maintaining remission in patients with ulcerative colitis.

SETTING

Public hospitals and private practices in Germany, Austria and Switzerland.

PATIENTS

A total of 162 patients with ulcerative colitis in remission.

RESULTS

According to intention-to-treat analysis, the failure rates of the different treatment groups were not significantly different (36, 49 and 24% for 0.5, 1.25 and 2.0 g olsalazine daily and 32% for 2.0 g sulphasalazine daily). Olsalazine and sulphasalazine showed a tendency towards lower failure rates in extended (28%) than in distal disease (44%). The withdrawal rate due to adverse effects was 4%, the most frequent single event being diarrhoea (2.5, 5.2 and 11.7% for 0.5, 1.25 and 2.0 g olsalazine daily and 0% for sulphasalazine daily).

CONCLUSION

This study found no significant differences between the therapeutic efficacy or safety of 0.5-2.0 g olsalazine daily. Because of its sulpha-free formulation olsalazine may, however, be preferred to sulphasalazine.

Amanita phalloides intoxications in a family of russian immigrants. Case reports and review of the literature with a focus on orthotopic liver transplantation

Alpha-amanitin, the main toxin of the death cap fungus (Amanita phalloides) is one of the most dangerous natural poison. This toxin damages eukaryotic cells by inhibiting their transcription. Lesions are seen in cells with rapid protein synthesis, particular in liver and renal cells, even at low toxin concentrations. Without adequate intensive therapy, the outcome of alpha-amanitin poisoning is very poor. This article reports various courses of amanitin intoxication in a family. In 3/4 patients, severe hepatic failure developed as assessed by a decrease of all coagulation factors, mainly Quick's test and factor V (< 10%-15%). Despite vigorous replacement of coagulation factors, in 1 of the patients orthotopic liver transplantation had to be performed on day 4, whereas in all other patients liver function improved spontaneously. All patients survived their intoxication. Both the pharmacological basis and clinical manifestations of Amanita intoxication are discussed. On this basis a treatment scheme is presented which the authors believe may be useful to clinicians.

Effect of olsalazine and mesalazine on human ileal and colonic (Na+ + K+)-ATPase. A possible diarrhogenic factor?

Olsalazine (azodisalicylate) and mesalazine (5-aminosalicylic acid) have recently been developed as new treatment modalities for inflammatory bowel disease to avoid sulfasalazine-related side effects. However, there are reports regarding new and hitherto unexpected side effects in some patients receiving olsalazine or mesalazine, such as watery diarrhea. Since sodium pump activities play an important role in the pathogenesis of water and electrolyte disturbances, we investigated the influence of olsalazine and mesalazine on human ileal and colonic (Na+ + K+)-ATPase and its specific [3H]-ouabain binding. We found a concentration-dependent inhibition of ileal and colonic (Na+ + K+)-ATPase by olsalazine with an IC50 of 4.1 mM and 4.8 mM, respectively. Mesalazine inhibited this enzyme in the ileum with an IC50 of 4.0 mM and in the sigmoid colon with an IC50 3.5 mM. In addition, [3H]-ouabain binding was inhibited by mesalazine with an IC50 of 3.6 mM. The maximal inhibition, however, did not exceed 80% under any conditions (up to 10 mM drug concentration). Olsalazine and mesalazine induce inhibition of the ileal and colonic sodium pump activities that may (in addition to other possible mechanisms) mediate impaired water and electrolyte absorption. This is possibly of clinical relevance in patients with severely damaged mucosa. In patients with milder forms of mucosal inflammation, this inhibition most likely is of minor importance because of the great capacity of the (Na+ + K+)-ATPase and the incomplete inhibition leaving at least 20% of the enzyme activity intact.

Olsalazine-related diarrhoea: does rat intestine adapt in vivo?

Diarrhoea may occur in up to 10% of patients with ulcerative colitis treated with olsalazine, the azolinked dimer of 5-aminosalicylic acid. However, this symptom often disappears despite continued drug medication. To examine reversibility of and adaptation to olsalazine effects on intestinal absorption, rats were fed olsalazine (4 mg/100 g body weight/day) for 0 (controls), 12, 24, and 32 days. Jejunal, ileal, and colonic loops were perfused in situ with buffer or olsalazine (11.6 mM) in a pendular perfusion system. Water and electrolyte absorption was inhibited in all intestinal segments (p less than 0.001). In the proximal small intestine, however, sodium absorption was inhibited by 61%, whereas chloride and potassium absorptions were turned into net secretion. In contrast, in ileal and colonic segments sodium, chloride, and potassium absorptions were turned into a net secretion. All inhibitory effects were reversible within a short time. Intestinal absorption remained inhibitable compared with controls (p = not significant) after chronic administration of olsalazine even for 1 month. Jejunal monosaccharide absorption was not altered by acute olsalazine perfusion. In the ileum, glucose absorption was significantly inhibited, but the inhibitory capacity of acute olsalazine application decreased significantly (p less than 0.05) depending on duration of olsalazine pretreatment (51% (controls) versus 38% (32 days)). These results point to a complex, acute, but fully reversible effect of olsalazine on intestinal passive and chloride-coupled absorptive processes. Since a mucosal adaptation to these diarrheogenic effects does not occur, the resulting increase in fluid load on the diseased colon may be important in the pathogenesis of olsalazine-related diarrhoea.

[Crohn disease in advanced age]

Crohn's disease of late onset (greater than 65 years) is rare condition. Typical features are the localisation in the distal gastrointestinal tract and the presence of associated diseases such as cardiovascular disorders and/or diverticulitis. In about 25% of the cases mild intestinal hemorrhage occurs. Delay in diagnosis is sometimes due to coexistent diverticulitis. Ischemia has been suggested to be responsible for the development of the histological changes which occur in Crohn's colitis. Therefore, we carried out a retrospective analysis of our patients treated between 1978-1988 to reevaluate the resected specimens. 10 patients (6.2% of all surgical patients with Crohn's disease) were at least 65 years old at the time of primary operation. In 5 cases hematochezia was one of the symptoms before operation, two patients presented with massive hemorrhage of the lower GI-tract. Granulomas were seen only in 5 patients, whereas in all specimens transmural inflammation was detected. In 8 out of 10 patients vascular lesions were seen, among those thickening of the intimal and medial layers, thrombosis or bleeding. Our findings support the thesis that ischemia might play a role in the pathogenesis of Crohn's disease of late onset.

[Changes in fecal composition, intestinal transit, bile acid metabolism and intestinal fermentation in long-term nutrition with high molecular weight formula diet]

Treatment with formula diets becomes more and more popular in many patients. The influence of those diets on gut functions is as yet poorly known. We studied in ten healthy volunteers the effects of a high molecular liquid diet. Despite of a sufficient energy supply the volunteers lost significantly weight which may be related to an acceleration of small bowel transit (60 +/- 9 min vs. 31 +/- 5 min; control vs. diet period). Whole gut transit did not change significantly (52 +/- 3 h vs. 56 +/- 3 h). The fecal excretion of bile acids decreased significantly (293 +/- 35 mg/24 h vs. 151 +/- 10 mg/24 h) which was particularly due to a decrease of primary bile acids. The serum bile acid concentrations behaved in a similar way (total bile acids: 3.19 +/- 0.66 mumol/l vs. 1.71 +/- 0.21 mumol/l). Neither the determination of unconjugated serum bile acids nor hydrogen breath testing did indicate increase of bacterial growth. In conclusion, chronic nutrition with formula diets causes significant changes of gut functions.

Effect of diets low and high in refined sugars on gut transit, bile acid metabolism, and bacterial fermentation

Increasing consumption of refined sugar has been implicated in many gastrointestinal disorders on epidemiological grounds. Nine volunteers agreed to participate in a study comparing the effects of a diet containing 165 g refined sugar/day with a diet of only 60 g/day on gut transit, bile acid metabolism, and fermentative activity of the intestinal flora. The wet and dry weight, pH, and water content of the stools were similar on the two diets. On the high sugar diet mouth-to-anus transit time was significantly prolonged, despite a shortened mouth-to-caecum transit time. The faecal concentration of total bile acids and the faecal concentration of secondary bile acids increased significantly. Diet affected neither the serum bile acid pattern nor the concentration. Breath hydrogen tests showed significantly enhanced H2 production on the high sugar diet. We conclude that the quantity of refined sugar in the diet can significantly influence gut function and the composition of bowel contents.

[Risk factors for the development of fistulas in Crohn disease]

The pathophysiology of fistula formation in Crohn's disease is as yet poorly known. We, therefore, studied in 111 patients with Crohn's disease factors which may be associated with the development of fistulas. Male patients, patients with exclusively involved colon or extended disease of the colon and ileum as well as patients treated with prednisone demonstrated an increased relative risk to develop fistulas. In patients with ileitis alone and after laparatomy in combination with resection of the bowel the relative risk was less than 1. Furthermore, in 71% of the patients fistulas developed during active disease. In 65% the patients had underweight at the time of fistula formation. We conclude, that the localization of the disease, a factor which can not be influenced, as well as active disease and malnutrition, both factors which can be influenced, may be involved in the formation of fistulas in Crohn's disease.

Small intestinal transit, bacterial growth, and bowel habits in diabetes mellitus

To investigate diabetic alterations of small intestinal transit and bacterial growth, we performed hydrogen breath tests (10 g lactulose via duodenal tube at the ligament of Treitz), bacterial cultures, and determinations of unconjugated serum bile acids in 19 patients with long-standing diabetes and 7 healthy controls. Asymptomatic diabetics had a late rise in breath hydrogen, indicating prolonged jejunal-cecal transit (86 +/- 10 min, p less than 0.05) as an early pathogenic event. Rise in breath hydrogen in symptomatic diabetics (constipation: 50 +/- 6 min; diarrhea: 41 +/- 11 min) was not significantly different from controls (57 +/- 8 min). Bacterial studies and increased unconjugated serum bile acids suggest bacterial overgrowth in some symptomatic diabetics. Bacterial overgrowth was associated more frequently (p less than 0.05) with a rise in breath hydrogen before 45 min or after 75 min. Changes in the hydrogen breath test, bacterial growth, or unconjugated serum bile acids did not correlate with gastrointestinal symptoms of diabetes.

Crohn's disease is frequently complicated by giardiasis

Giardiasis is a common infection, and many of its symptoms are similar to those of Crohn's disease. Despite a long discussion on the role of microbiologic agents in Crohn's disease, giardiasis has never been investigated. We studied giardiasis as assessed by the occurrence of cysts in 86 patients with Crohn's disease, in 82 patients with other gastrointestinal disease, and in 52 patients without gastrointestinal disease. In addition, in 20 patients with Crohn's disease the effects of metronidazole on giardiasis and disease activity were studied. Frequency of giardiasis was 61.6% in patients with Crohn's disease, 31.7% in patients with other gastrointestinal disease, and 5.8% in the control group (p less than 0.01). Stool frequency, disease activity, and humoral signs of inflammation in patients with Crohn's disease showed no relationship to giardiasis. All but two patients treated with metronidazole became free of cysts. Crohn's disease activity index decreased in 14 of 20 patients (p less than 0.05). In conclusion, giardiasis is a common finding in patients with Crohn's disease. Treatment of giardiasis can, in individual cases of Crohn's disease, result in a quick recovery from symptoms of high disease activity.

[Exchange transfusion and (or) plasmapheresis: effective measures in severe tropical malaria?]

A 42-year-old man was admitted to hospital with, previously wrongly diagnosed, fulminant falciparum malaria, 14 days after a two-week trip to Kenya. He had a high fever and was jaundiced, with severe anaemia and thrombocytopenia. He was given quinine intravenously and pyrimethamine/sulfadoxine (Fansidar) by mouth. He developed acute renal failure and increasingly severe cerebral symptoms, at times coma. An exchange transfusion and several plasmaphereses were, therefore, performed. The cerebral symptoms quickly abated during the exchange transfusion, but renal function failed to improve. Because of continuing fever, mefloquin (Lariam) and doxy-cycline (Vibramycin) were also administered. After several dialysis periods the patient improved gradually and was discharged after three weeks in generally good condition with normal renal function.

Accuracy of the whole body retention half-life of 75SeHCAT in the diagnosis of ileal dysfunction in patients with Crohn's disease

The measurement of the whole body retention of the synthetic taurine conjugated trihydroxy bile acid 75SeHCAT has been suggested as a new clinical test for the function of the terminal ileum. Because of the frequent occurrence of ileal dysfunction in Crohn's disease (CD), the accuracy of the SeHCAT test was studied in 64 patients with CD in various clinical conditions. A positive test result (retention half-life less than 1.2 days) was seen in 48.4% of the patients with ileal involvement (true positive tests) whereas a negative test was seen in 33 of the 64 patients. In 21 of the 33 patients (63.6%) the test was false negative since ileal inflammation or resection was confirmed by radiology or endoscopy. In 14 of those 21 patients with false negative test results a stenosis of the intestinal lumen was diagnosed. At a specificity of 100% the sensitivity of the SeHCAT test was 59.6% and the efficiency was 67.2%. If patients with known stenosis were excluded sensitivity improved to 79.4%. In conclusion, calculation of the whole body retention half-life of SeHCAT does not seem to be a valuable screening test for the diagnosis of ileal dysfunction. In CD, a pathologic test result identifies ileal dysfunction with high accuracy.

Comparison of 75SeHCAT retention half-life and fecal content of individual bile acids in patients with chronic diarrheal disorders

Measurement of the retention of 23-75Se-25-homotaurocholic acid (SeHCAT) has been suggested as a new test for ileal function. We investigated 31 patients with chronic diarrhea, 10 with ileal Crohn's disease and 21 with diarrhea but without ileal disease. The whole-body retention half-life of 1 mu Ci SeHCAT was determined and compared to the fecal content of total and individual bile acids. Patients with ileal disease had increased primary fecal bile acids (chenodeoxycholic acid: mean 6.95 mg/g dry weight, range 3.15-10.6 mg/g; cholic acid: mean 18.15 mg/g, range 10.3-33.9 mg/g) and a short SeHCAT retention (mean 11.9 h, range 2-24 h), whereas patients with intact ileum had normal fecal bile acids and a SeHCAT retention of 85.9 h (range 28-216 h). SeHCAT retention half-life differentiated well between patients with ileal disease and patients with normal ileum, thus indicating the SeHCAT test as a valid investigation method for detection of primary bile acid malabsorption in patients with chronic diarrhea and ileal dysfunction.