Elektrophysiologische Grundlagen der Hybrid-Therapie: Wie kommt es zur Konversion von Vorhofflimmern in Vorhofflattern?

Zusammenfassung Vorhofflimmern liegen mehrere simultan existierende, r?umlich und zeitlich variierende atriale Reentry-Ph?nomene zugrunde. Grundlage von Vorhofflattern ist ein stabiles singul?res Makro-Reentry im rechten Vorhof. Spontane überg?nge von Vorhofflimmern in anhaltendes Vorhofflattern sind selten, werden bei antiarrhythmischer Dauermedikation aber in ca. 10% der F?lle beobachtet. Der Konversion liegt die Bildung eines ausgedehnten funktionellen rechtsatrialen Leitungsblockes im Bereich der bereits physiologisch anisotrop leitenden Crista terminalis zugrunde. Hierdurch werden multiple variable Reentry-Ph?nomene verhindert und das typische rechtsatriale Makroreentry von Vorhofflattern begünstigt. Durch eine spezifische antiarrhythmische Medikation wird die transversale Leitungskapazit?t der Crista terminalis herabgesetzt und die Bildung einer Leitungsblockierung erleichtert. Sind linksatriale Reentry-Ph?nomene für die Aufrechterhaltung von Vorhofflimmern ausreichend, führt die Ausbildung eines funktionellen Leitungsblockes im Bereich der Crista terminalis nicht zu einer anhaltenden Konversion in Vorhofflattern. Sind jedoch rechtsatriale Reentry-Ph?nomene am Vorhofflimmern beteiligt, kann nach Leitungsblockierung stabiles Vorhofflattern beobachtet werden. Correspondence to B. Schumacher     

Epidemiologie und Ursachen von Vorhofflimmern

Zusammenfassung Vorhofflimmern ist die h?ufigste, behandlungsbedürftige Herzrhythmusst?rung mit einer altersabh?ngigen Pr?valenz von 0,4–10%. Aufgrund der noch immer geringen Effizienz medikament?ser Therapien zur Konversion und Erhalt eines stabilen Sinusrhythmus und des zunehmenden Anteils ?lterer Menschen in unserer Bev?lkerung kommt der Diagnostik und Therapie des Vorhofflimmerns eine betr?chtliche Bedeutung zu.    Vorhofflimmern stellt keine homogene Arrhythmie dar, sondern basiert vielmehr auf einem weiten Spektrum unterschiedlicher ?tiologischer Faktoren. H?ufig ist Vorhofflimmern somit nicht als eigenst?ndiges Krankheitsbild, sondern vielmehr als Symptom einer zugrundeliegenden Erkrankung anzusehen. Die dabei h?ufigsten kardialen Erkrankungen sind die Herzinsuffizienz, die koronare Herzerkrankung, das Cor hypertensivum und Herzklappenfehler. Jedoch auch postoperativ nach kardiochirurgischen Eingriffen ist das Vorhofflimmern von hoher Bedeutung.    Die Lebensqualit?t der Patienten mit Vorhofflimmern kann aufgrund zahlreicher klinischer Symptome deutlich reduziert sein. Komplizierend weisen Patienten mit Vorhofflimmern ein mit dem Alter zunehmendes Schlaganfallrisiko sowie eine erh?hte Mortalit?t auf.    Kontovers diskutiert wird die Frage, ob das Vorhofflimmern selbst die erh?hte Mortalit?t verursacht oder nicht vielmehr die zugrundeliegenden Erkrankungen sowie die begleitenden Komplikationen hierfür verantwortlich sind, denn das Auftreten von Vorhofflimmern ist h?ufig Ausdruck einer fortgeschrittenen Herzinsuffizienz oder einer schweren koronaren Herzerkrankung.    Die Diagnostik und Therapie des Vorhofflimmerns sollte sich daher in erster Linie auf die Erkennung und Behandlung der m?glicherweise urs?chlichen Grunderkrankung sowie die Pr?vention assoziierter Komplikationen stützen. Eingegangen: 5. Mai 2001 Akzeptiert: 15. Mai 2001     

Die Situation von PflegeheimbewohnerInnen mit Kontinenzproblemen: eine Studie in 2 deutschen Pflegeheimen

Zusammenfassung Ziel   Beschreibung der Situation von BewohnerInnen mit Kontinenzproblemen in zwei deutschen Pflegeheimen. Methoden   Systematische Analyse der Bewohnerdokumentation und Befragung der betreuenden Pflegekr?fte durch spezialisierte Pflegefachkr?fte (Kontinenzberaterin und Pflegewissenschaftlerin) und Geriater anhand eines standardisierten Protokolls. Qualitative Methoden wie Focusgruppen und teilnehmende Beobachtung wurden zur Gewinnung zus?tzlicher Informationen eingesetzt. Ergebnisse   In den beiden Pflegeheimen wurden 177 BewohnerInnen mit und 70 ohne, Kontinenzprobleme erfasst (81,4% Frauen, mittleres Alter 83,7 Jahre). Für die 247 BewohnerInnen waren 57 Haus?rzte und 116 Pflegekr?fte zust?ndig. 71% der Bewohnerinnen und 76% der Bewohner zeigten mindestens ein Kontinenzproblem. Die drei h?ufigsten Kontinenzprobleme der BewohnerInnen waren kombinierte Harn- und Stuhlinkontinenz (32%), isolierte Harninkontinenz (21%) und Blasenverweilkatheter (17%). Bei funktionellen F?higkeiten wie Toilettengang, Ankleiden und kognitiven Leistungen wie der Orientierung zur Situation waren BewohnerInnen mit Kontinenzproblemen signifikant h?ufiger auf personelle Hilfe angewiesen (P < 0,01) als BewohnerInnen ohne Kontinenzprobleme. Bei 64% der BewohnerInnen war kein Arzt zur Kontinenzproblematik konsultiert worden und bei 86% waren Angeh?rige nicht in kontinenzrelevante T?tigkeiten einbezogen. Schlussfolgerung   Kontinenzprobleme haben bei PflegeheimbewohnerInnen eine hohe Pr?valenz und gehen mit komplexen funktionellen Einschr?nkungen sowie erheblicher Komorbidit?t einher. Sowohl die fachliche als auch die ?ffentliche Auseinandersetzung mit Kontinenzproblemen von PflegeheimbewohnerInnen muss vorangetrieben werden, um langfristig Ver?nderungen zu bewirken. Mit „BewohnerInnen“ sind in dieser Arbeit sowohl Bewohnerinnen als auch Bewohner gemeint.     

Tabu und Stigma in der Versorgung von Patienten mit Demenz

One of the main reasons for deficits in the care of patients with dementia is the taboo on the disease and the stigma of the people suffering from the disease, also from the side of the professional caregivers. The aim of the project was to find out whether a continuing education program for GPs and for nurses in ambulatory care was able to increase the skills of professionals to better communicate with patients and relatives on the taboo topic of dementia. The program was developed with a multi-professional team and tested with 53 GPs and 54 nurses in ambulatory care. The evaluation was performed with a 39-item questionnaire administered before and after the training. Also, to test the stability of the outcomes, the same questionnaire was administered to the GPs after one year and after two months for the nurses. The process quality of the training was evaluated very positively in both groups. Outcome quality was also very positive. Many attitudes of the GPs changed in a positive way and this change was still present after one year. This was the case for their general attitude towards caring for people with dementia, their view on therapeutic possibilities, their willingness to support relatives, to refer them to the Alzheimer Society and to suggest to them participation in a self-help group. Results for the nurses pointed in the same direction. However, with regard to diagnosis disclosure and informing the patient, no effect of the training could be shown in the GP sample.     

Pathophysiologie und Keimspektrum der Sepsis

Zusammenfassung  Die Pathophysiologie der Sepsis ist bisher nur unvollst?ndig verstanden. Bakterien sind die Hauptausl?ser einer Sepsis. Die Aktivierung von Rezeptoren der angeborenen Immunit?t bewirkt eine ausgedehnte Immunantwort. Aktivierte neutrophile Granulozyten und Makrophagen produzieren und reagieren auf eine Vielzahl von Zytokinen, Chemokinen, Komplementfaktoren und anderen Mediatoren. Diese proinflammatorischen Stimuli bewirken die Freisetzung sekund?rer Mediatoren wie z. B. Lipide und reaktive Sauerstoffradikalen, welche die Entzündungsreaktion weiter verst?rken. Bei Verlust von Kontrollmechanismen im Rahmen der Sepsis führt diese überaktivierung der Immunantwort schlie?lich zu einer Sch?digung des eigenen Organismus. Initial dominiert eine proinflammatorische Reaktion, wohingegen in den sp?ten Stadien der Sepsis antiinflammatorische Mechanismen bis hin zur Immunanalyse überwiegen. In der vorliegenden übersicht werden die derzeitigen Erkenntnisse zum Zusammenspiel der verschiedenen pathophysiologischen Mechanismen und Systeme im Rahmen des komplexen und dynamischen Krankheitsbilds der Sepsis dargestellt, sodass auch m?gliche therapeutische Interventionen eingeordnet werden k?nnen.

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Aktuelle Diagnostik und Therapie der akuten Lungenembolie

Diagnosing pulmonary embolism (PE) remains a challenge due to the often confusing clinical presentation of the disease. Plasma D-dimer testing with ELISA is increasingly becoming part of the initial diagnostic work up. Due to the high specificity of the assay, a negative test can reliably exclude PE. Importantly, massive PE can be promptly diagnosed or excluded by echocardiography which is a particularly valuable noninvasive method for detection of right ventricular dysfunction at the bedside. High-risk patients can thus be identified and treated immediately without further time-consuming examinations. Confirmation of PE in patients with inconclusive or normal echocardiograms is often based on lung scans, but diagnostic uncertainty is common with this procedure. The popularity of pulmonary angiography is decreasing due to its invasiveness, whereas spiral CT appears to be a promising alternative. Search for (residual) deep vein thrombosis is useful for guiding therapy in stable patients with small pulmonary emboli, since their risk is determined by the potential for PE recurrence. Recent evidence confirmed that right ventricular dysfunction predicts an unfavorable prognosis and might therefore justify thrombolytic treatment of massive PE regardless of systemic hemodynamics. On the other hand, simplified anticoagulation regimens with low-molecular weight heparins have yielded very promising results in stable patients. These diagnostic and therapeutic principles based on cardiovascular risk stratification will hopefully result in a more effective approach to patients with venous thromboembolism in the future.     

Chancen und Risiken der chirurgischen Adipositastherapie

News headlines around the world read “Obesity Surgery Can Cure Diabetes” following the first randomized controlled study of the effect of laparoscopic adjustable gastric banding (LAGB) on type 2 diabetes was published today in the Journal of the American Medical Association (JAMA). As bariatric and metabolic surgeons we have known this for years, but today’s study, along with the two landmark studies published in The New England Journal of Medicine in August 2007 that showed a significant increase in survival among people who have bariatric surgery, provide new and important evidence that this type of surgery saves lives and can eliminate, or dramatically improve, disease. The risks of the surgery are less than the existing combination of obesity with metabolic syndrome. Surgery in overweight and obese patients is the most effective treatment for diabetes.     

ACE-Gen-Polymorphismus und kardiovaskuläre Erkrankungen

The angiotensin converting enzyme (ACE) is an integral part of enzymatic cascades leading to generation of angiotensin II as well as degradation of bradykinin. For this reason, it represents an important part for the metabolism of 2 vasoactive peptides. Early in this decade, convincing experimental evidence demonstrated the induction of this enzyme in several pathophysiological conditions including myocardial infarction and left ventricular hypertrophy. In parallel, a deletion/insertion (D/I) polymorphism of the human ACE gene was discovered that was related to 14 to 50% of the interindividual variance of serum ACE activity. More recently, this polymorphism was implicated in the pathogenesis of a variety of cardiovascular disorders including myocardial infarction, left ventricular hypertrophy, hypertension as well as nephropathy.     

Vorhofflimmern

Zum Thema Vorhofflimmern ist die h?ufigste, behandlungsbedürftige Herzrhythmusst?rung. Aufgrund der noch immer geringen Effizienz medikament?ser Therapien zur Konversion und Erhalt eines stabilen Sinusrhythmus und seiner gravierenden Komplikationen, insbesondere des Schlaganfalls, kommt der Diagnostik und Therapie des Vorhofflimmerns eine betr?chtliche sozialmedizinische Bedeutung zu. In der folgenden übersicht werden zun?chst die Definition, Klassifikation, Pr?valenz, Symptome und Risikofaktoren des Vorhofflimmerns beschrieben, soweit diese für die Therapieentscheidungen relevant sind. Nachfolgend wird der Literaturstand zur Antikoagulation bei Patienten mit Vorhofflimmern zusammenfassend dargestellt. Abschlie?end wird der heutige Kenntnisstand in der medikament?sen und katheterinterventionellen Therapie erl?utert.     

EMG-Mapping versus Endosonographie: Der Vergleich ist entschieden

The detection or exclusion of a sphincter damage plays an important role in the diagnosis of anal incontinence as well as in preoperative diagnostic measures. The apparative diagnosis must show a high validity and must have a clear superiority to digital examination. This was possible in the past with the aid of EMG mapping. During more recent years introduction of anal sonography superseded the latter, because this new method is less invasive, is more readily available in coloproctological departments and most possibly shows a superior diagnostic validity. The EMG mapping has its place in sonographically uncertain findings and in cases where only an EMG and no sonography is available. To clarify a neurogenic damage the needle EMG is by far the most secure method.     

Ergotamininduzierte Rektumläsionen

Within 11 years we found anorectal ergotism in 15 patients, showing anorectal lesions and even fistulae. Therefore we prospectively examined 60 patients (49 female, 11 male: 43.7 years on average) with known long-term ergotamine suppository abuse (7.2+4.7 years on average). No serious ulcerations were found. In 4 cases local blood circulation was reduced. In 8 patients increased blood circulation in the anterior rectal wall was observed, in 3 of them and in 1 further patient associated with local hyperemia and a small bleeding. We conclude that anorectal ergotism is a possible although rare sequela of ergotamine suppository abuse. For long-term treatment of migraine other therapeutic substances are recommended.     

Morphometrie der Ganglien und Nervenzellen des Plexus submucosus bei der intestinalen neuronalen Dysplasie des Erwachsenen

Intestinal neuronal dysplasia is a developmental abnormality of the plexus submucosus in the colon. In recent years this initially in children described dysganglionosis has also been found in adults with chronic constipation. The aim of this study was a morphometric characterization of intestinal neuronal dysplasia in the submucous plexus of adults. Biopsies of 10 adults with intestinal neuronal dysplasia were compared with biopsies of 10 healthy controls. Nerve cells and ganglia were stained selectively with a lactate dehydrogenase reaction. Morphometry was made with an optic electronic analysis system. The detection of 6 to 10 giant ganglia with more than 7 nerve cells in 15 biopsy sections proved to be the most characteristic diagnostic indicator of intestinal neuronal dysplasia. The number of giant ganglia in the submucous plexus was 20%. For a quantitative objectivation of intestinal neuronal dysplasia 15 biopsy sections with enough submucosa are necessary.     

Alkohol, Alter und Verkehr

The roadworthiness of older people is affected by internal, neurological or orthopedic diseases and by the medication. These factors have an effect on alcohol tolerance. Therefore, alcoholization in elderly drivers needs specific attention. A retrospective evaluation of all alcoholized traffic participants ?>?60 years of age between 2003–2008 in Hamburg is described. The data analysis gives information about the alcohol level in various age groups, the resulting neurological/physiological deficits, chronic illnesses and the medications taken. The proportion of elderly people involved in a traffic delinquency has increased. However, the absolute number of old drunk drivers has decreased. Seniors are represented significantly less often concerning alcohol in traffic than other age groups.     

Thrombolyse mit Alteplase 3 bis 4.5 Stunden nach akutem isch?mischen Schlaganfall

Intravenous thrombolysis with alteplase is the only approved treatment for acute ischemic stroke. It is approved to be administered within 3 hours after the onset of stroke. In 1995, the National Institute of Neurological Disorders and Stroke (NINDS) study group reported that patients with acute ischemic stroke who received alteplase within 3 hours after the onset of symptoms were at least 30% more likely to have minimal or no disability at 3 months than those who received placebo. In a subsequent analysis of the NINDS study and the combined analysis of data from six randomized trials, which investigated thrombolysis treatment for ischemic stroke in a total of 2775 patients, a favorable outcome was observed even if treatment was given between 3 and 4.5 hours. International guidelines recommend alteplase as a first-line treatment when administered within 3 hours after the onset of stroke. Despite this recommendation, it is estimated that fewer than 2% of patients receive this treatment in most countries, primarily because of delayed admission to a stroke center. The European Cooperative Acute Stroke Study (ECASS) III, a randomized, double-blind, placebo-controlled phase 3 trial was designed to test the hypothesis that the efficacy of alteplase administered in patients with acute ischemic stroke can be safely extended to a time window of 3 to 4.5 hours after the onset of stroke symptoms. A total of 821 patients with acute ischemic stroke were assigned to a study group 3 to 4.5 hours after onset of stroke symptoms. 418 patients were randomized assigned to receive alteplase and 403 patients were assigned to receive placebo. The primary end point was disability at day 90 after stroke, dichotomized as a favorable outcome (a score of 0 or 1 on the modified Rankin scale, which has a range of 0 to 6, with 0 indicating no symptoms at all and 6 indicating death) or an unfavorable outcome (a score of 2 to 6 on the modified Rankin scale). As compared with placebo, intravenous alteplase administered 3 and 4.5 hours after the onset of symptoms significantly improved clinical outcome in patients with acute ischemic stroke. The incidence of intracranial hemorrhage was higher with alteplase than with placebo. Mortality did not differ significantly. Still the effect size of thrombolysis is time-dependant. Early treatment shows higher efficacy and remains essential. Until now there is no approval for the treatment with alteplase in the extended time window and therefore it can only be applied as a individual therapeutic option.     

Verbesserung der Endokarderkennung mittels modifizierter transthorakaler Echokardiographie unter Verwendung der zweiten harmonischen Schwingungen (Tissue Harmonic Imaging)

In human tissue sound propagation is not linear resulting in a modification of the ultrasound waves. Therefore the received ultrasound frequencies are not just the transmitted frequencies of the transducer, but contain additional harmonic frequencies. These frequencies were not used by standard echocardiography. Harmonic imaging processes the second harmonic frequency. Distortion of the transmitted beam by shallow surface layers or reverberations between the skin surface and ribs impair image quality in conventional 2-dimensional echocardiography. Since harmonic components develop with propagation distance, the reverberations are almost entirely made up of ultrasound energy at the fundamental frequency. The exclusive processing of the second harmonic frequency provides an impressive improvement in image quality of 2-dimensional echocardiograms. Noise and clutter artifacts are reduced and endocardial borders are enhanced. Commercially available imagers provide tissue harmonic imaging using transmit frequencies from 1.7 to 2.1 MHz and second harmonic frequencies between 3.4 and 4.2 MHz. Several clinical studies have shown that harmonic imaging was superior to standard echocardiography in the assessment of left ventricular (LV) wall motion by LV wall motion analysis. In patients with poor acoustic windows the number of myocardial segments which could be evaluated was significantly higher using harmonic imaging than standard echocardiography. Tissue harmonic imaging particularly improves the delineation of the anterior wall using the 2-chamber view and the lateral wall using the 4-chamber view. CONCLUSION: Harmonic imaging is a clinically relevant improvement of echocardiography. We suggest that this new technology should be the method of choice in the evaluation of LV function.     

Shunt, Dialyseeinleitung, Katheter

The elective start of dialysis therapy via a well planned dialysis access requires early presentation at a nephrologist. Native fistulas, with their numerous modifications, are considerably superior to polytetrafluoroethylene (PTFE) grafts, both in terms of patient survival as well as infection and occlusion rates. Native fistulas should be placed at least 3 months and PTFE grafts 4 weeks prior the start of dialysis. If fistulas or PTFE grafts are not possible, or there are other contraindications such as severe heart insufficiency, dialysis should be started with a tunnelled catheter for vascular access. In Germany, dialysis is currently started at a mean GFR of 7.8 ml/min. Starting at <6 ml/min should definitely be avoided. In case of multimorbid patients, an earlier start may be necessary, exceptionally at a GFR >15 ml/min.     

Gutes Outcome trotz rezidivierender Subarachnoidalblutung bei Vertebralisaneurysma mit Komaeintritt und Atemstillstand – Ein Fallbericht

Rebleeding is one of the major causes of fatal outcome in subarachnoid hemorrhage. The case reported demonstrates a good outcome despite a rebleeding event with sudden respiratory arrest. A 55-year-old male with history of hypertension developed a strong headache over a period of two days. The headache became aggravated during the second night. First examined at Hunt amp Hess grade II in a peripheral hospital, a subarachnoid hemorrhage was identified by computed tomography. After transfer and computed angiography, the patient suffered a rebleeding accompanied by loss of consciousness and sudden respiratory arrest. After stabilization, an aneurysm of the left vertebral artery was closed interventionally by sealing the vertebral artery proximal to the aneurysm. The patient regained consciousness after several days of intensive care and was transferred to a rehabilitation hospital after 28 days. A rebleeding event accompanied by sudden respiratory arrest in subarachnoid hemorrhage does not represent an inevitably poor outcome. Fast and experienced management of interventional therapy can assure survival and a good outcome.     

Vorhofflimmern bei Schrittmacher- behandlung – Physiologische versus VVI Stimulation

Zusammenfassung Die prospektiven Studien zur Herzschrittmachertherapie bei Patienten mit paroxysmalem Vorhofflimmern zeigten keine übereinstimmenden Befunde. Eine Suppression der Vorhoftachyarrhythmien gelingt am ehesten bei Patienten mit Bradykardie-Tachykardie-Syndrom und hoher Stimulationsrate. Hinsichtlich einer Verbesserung der Prognose, der H?ufigkeit von Thromboembolien, der Rehospitalisierung und einer Verringerung der Herzinsuffizienz sind die Aussagen verschiedener Untersuchungen kontrovers. Die Lebensqualit?t ist in einigen Studien bei vorhofbeteiligter Stimulation verbessert. Die vorliegende Arbeit gibt einen überblick über vorliegende und gegenw?rtig laufende Studien. Eingegangen: 10. Januar 2002 Akzeptiert: 30. Januar 2002     

Moderne Bildgebung von Raumforderungen der Niere

Noninvasive imaging of renal masses has improved in recent years. Five different techniques are now available for a stepwise diagnostic procedure. While renal ultrasound and color Doppler sonography are used for tumor screening, computed tomographic angiography remains the imaging technique of choice for grading and classifying cystic and solid renal masses. In patients with allergies to iodinated contrast media or with renal insufficiency, magnetic resonance tomography (MRT) can play a major role, especially for cystic renal masses. However, nephrogenic systemic fibrosis has been recently described in more than 200 cases after MRT-associated application of gadolinium-based contrast media, thus currently limiting the use of MRT. Positron emission tomography should be limited to patients under surveillance or with suspected metastatic lesions. Recent developments in imaging techniques with new classifications to improve diagnostic accuracy are discussed in this article.