Natural History of Perianal Fistulising Lesions in Patients With Elderly-onset Crohn's Disease: A Population-based Study

INTRODUCTION

Most studies of elderly-onset Crohn's disease [CD; diagnosed in patients aged 60 or over] have described a mild course. However, data on the natural history of perianal fistulising CD [pfCD] in this population are scarce. In a population-based cohort study, we described the prevalence, natural history, and treatment of pfCD in patients with elderly-onset CD vs patients with paediatric-onset CD.

METHOD

All patients diagnosed with CD at or after the age of 60 between 1988 and 2006, were included [n = 372]. Logistic regression, Cox models, and a nested case-control method were used to identify factors associated with pfCD.

RESULTS

A total of 34 elderly patients [9% of the 372] had pfCD at diagnosis. After a median follow-up of 6 years (interquartile range [IQR]: 3; 10), 59 patients [16%] had pfCD; the same prevalence [16%] was observed in paediatric-onset patients. At last follow-up, anal incontinence was more frequent in elderly patients with pfCD than in elderly patients without pfCD [22% vs 4%, respectively; p < 10-4]. Rectal CD at diagnosis was associated with pfCD: hazard ratio (95% confidence interval [CI] = 2.8 [1.6-5.0]). Although 37% of the patients received immunosuppressants and 17% received anti-tumour necrosis factor agents, 24% [14 out of 59] had a definitive stoma at last follow-up.

CONCLUSION

During the first 6 years of disease, the prevalence of pfCD was similar in elderly and paediatric patients. Rectal involvement was associated with the appearance of pfCD in elderly-onset patients. Around a quarter of patients with elderly-onset CD will have a stoma. Our results suggest that treatment with biologics should be evaluated in these patients.

Liquid Chromatographic Determination of Residual Nitrite/Nitrate in Foods: NMKL Collaborative Study

Nitrite and nitrate are used as additives in the food industry to provide color and taste and to control undesirable gas and flavor production by anaerobic bacteria by virtue of their antimicrobial properties. The analytical method that has been widely used to determine nitrite and nitrate involves the use of toxic cadmium. In response to a request from the Nordic Committee on Food Analysis, a study was performed to obtain an alternative chromatographic method to determine residual nitrite and nitrate in meat products. The study was done in 3 stages: (1) comparative evaluation of the performance of 3 liquid chromatographic methods, (2) internal validation of the selected ion chromatographic method, and (3) a collaborative study in which 17 laboratories from European countries participated. Furthermore, the applicability of the method to matrixes other than meat and meat products was demonstrated. The results of the collaborative study show that the European Prestandard prENV 12014-4 is well suited for the determination of nitrite and nitrate in different foods (e.g., meat products, vegetables, baby food, and cheese). The limits of detection for nitrite and nitrate ions are 1 and 10 mg/kg, respectively. Recoveries of residual nitrite/nitrate ranged from 96 to 108%. Repeatability and reproducibility were satisfactory.

Extra-intestinal Manifestations at Diagnosis in Paediatric- and Elderly-onset Ulcerative Colitis are Associated With a More Severe Disease Outcome: A Population-based Study

BACKGROUND AND AIMS

Data on extra-intestinal manifestations [EIM] and their impact on the disease course of ulcerative colitis [UC] in population-based cohorts are scarce, particularly in paediatric- and elderly-onset UC patients. The aims of this population-based study were to assess: 1] the occurrence of EIM in paediatric- and elderly-onset UC; 2] the factors associated with EIM; and 3] their impact on long-term disease outcome.

METHODS

Paediatric-onset [< 17 years at diagnosis] and elderly-onset UC patients [> 60 years at diagnosis] from a French prospective population-based registry [EPIMAD] were included. Data on EIM and other clinical factors at diagnosis and at maximal follow-up were collected.

RESULTS

In all, 158 paediatric- and 470 elderly-onset patients were included [median age at diagnosis 14.5 and 68.8 years, median follow-up 11.2 and 6.2 years, respectively]. EIM occurred in 8.9% of childhood- and 3% of elderly-onset patients at diagnosis and in 16.7% and 2.2% of individuals during follow-up [p < 0.01], respectively. The most frequent EIM was joint involvement [15.8% of paediatric onset and 2.6% of elderly-onset]. Presence of EIM at diagnosis was associated with more severe disease course [need for immunosuppressants or biologic therapy or colectomy] in both paediatric- and elderly-onset UC (hazard ratio [HR] = 2.0, 95% confidence interval [CI]: 1.0-4.2; and HR = 2.8, 0.9-7.9, respectively). Extensive colitis was another independent risk factor in both age groups.

CONCLUSIONS

Elderly-onset UC patients had lower risk of EIM either at diagnosis or during follow-up than paediatric-onset individuals. EIM at diagnosis predicted more severe disease outcome, including need for immunosuppressive or biologic therapy or surgery, in both paediatric- and elderly-onset UC.

The concept of locking plates

After a short historical review of locking bone plates since their inception more than a century ago to the success of the concept less than 15 years ago with today's plates, the authors present the main locking mechanisms in use. In the two broad categories - plates with fixed angulation and those with variable angulation - the screw head is locked in the plate with a locknut by screwing in a threaded chamber on the plate or by screwing through an adapted ring. The authors then provide a concrete explanation, based on simple mechanical models, of the fundamental differences between conventional bone plates and locking plates and why a locking screw system presents greater resistance at disassembly, detailing the role played by the position and number of screws. The advantages of epiphyseal fixation are then discussed, including in cases of mediocre-quality bone. For teaching purposes, the authors also present assembly with an apple fixed with five locking screws withstanding a 47-kg axial load with no resulting disassembly. The principles of plate placement are detailed for both the epiphysis and diaphysis, including the number and position of screws and respect of the soft tissues, with the greatest success assured by the minimally invasive and even percutaneous techniques. The authors then present the advantages of locking plates in fixation of periprosthetic fractures where conventional osteosynthesis often encounters limited success. Based on simplified theoretical cases, the economic impact in France of this type of implant is discussed, showing that on average it accounts for less than 10% of the overall cost of this pathology to society. Finally, the possible problems of material ablation are discussed as well as the means to remediate these problems.

Fluid shear stress induction of COX-2 protein and prostaglandin release in cultured MC3T3-E1 osteoblasts does not require intact microfilaments or microtubules

Cultured osteoblasts express three major types of cytoskeleton: actin microfilaments, microtubules, and intermediate filaments. The cytoskeletal network is thought to play an important role in the transmission and conversion of a mechanical stimulus into a biochemical response. To examine a role for the three different cytoskeletal networks in fluid shear stress-induced signaling in osteoblasts, we individually disrupted actin microfilaments, micro-tubules, and intermediate filaments in MC3T3-E1 osteoblasts with multiple pharmacological agents. We subjected these cells to 90 min of laminar fluid shear stress (10 dyn/cm(2)) and compared the PGE(2) and PGI(2) release and induction of cyclooxygenase-2 protein to control cells with intact cytoskeletons. Disruption of actin microfilaments, microtubules, or intermediate filaments in MC3T3-E1 cells did not prevent a significant fluid shear stress-induced release of PGE(2) or PGI(2). Furthermore, disruption of actin microfilaments or microtubules did not prevent a significant fluid shear stress-induced increase in cyclooxygenase-2 protein levels. Disruption of intermediate filaments with acrylamide did prevent the fluid shear stress-induced increase in cyclooxygenase-2 but also prevented a PGE(2)-induced increase in cyclooxygenase-2. Thus none of the three major cytoskeletal networks are required for fluid shear stress-induced prostaglandin release. Furthermore, although neither actin microfilaments nor microtubules are required for fluid shear stress-induced increase in cyclooxygenase-2 levels, the role of intermediate filaments in regulation of cyclooxygenase-2 expression is less clear.

Hepatocellular carcinoma associated with precocious puberty and oral contraceptives. A case report

A 36-year-old woman presented with sudden abdominal pain and vomiting. Computed tomography showed a tumour of the right hepatic lobe with possible signs of acute haemorrhage. Her medical history revealed precocious puberty when she was a 5-year-old and the use of oral contraceptives for 18 years. Bisegmentectomy was performed and histological examination revealed hepatocellular carcinoma. The role of male and female sex hormones in the development of hepatic tumours has been well documented but, to our knowledge, association with precocious puberty has not yet been described.

Osteoblast intracellular localization of Nmp4 proteins

Nmp4 proteins are transcription factors that contribute to the expression of type I collagen and many of the matrix metalloproteinase genes. Numerous Nmp4 isoforms have been identified. These proteins, all derived from a single gene, have from five to eight Cys(2)His(2) zinc fingers, the arrangement of which directs specific isoforms to nuclear matrix subdomains. Nmp4 isoforms also have an SH3 binding domain, typical of cytoplasmic docking proteins. Although recent evidence indicates that Nmp4 proteins also reside in the osteoblast cytoplasm, whether they localize to specific organelles or structures is not well defined. The intracellular localization of a protein is a determinant of its function and provides insights into its mechanism of action. As a first step toward determining the functional relationship between the cytoplasmic and nuclear Nmp4 compartments, we mapped their location in the osteoblast cytoplasm. Immunocytochemical analysis of osteoblasts demonstrated that Nmp4 antibodies labeled the mitochondria, colocalized with Golgi protein 58K, and lightly stained the cytoplasm. Western analysis using Nmp4 antibodies revealed a complex profile of protein bands in the nuclear, mitochondrial, and cytosolic fractions. Several of these proteins were specific to defined intracellular domains. Consistent with the western analyses, reverse transcription-polymerase chain reaction (RT-PCR) analysis detected previously uncharacterized Nmp4 isoforms. These data necessarily enlarge the known Nmp4 family from nuclear matrix transcription factors to a more widely extended class of intracellular proteins.

Influence of plasminogen activator inhibitor type 1 on choroidal neovascularization

High levels of the plasminogen activators, but also their inhibitor, plasminogen activator inhibitor 1 (PAI-1), have been documented in neovascularization of severe ocular pathologies such as diabetic retinopathy or age-related macular degeneration (AMD). AMD is the primary cause of irreversible photoreceptors loss, and current therapies are limited. PAI-1 has recently been shown to be essential for tumoral angiogenesis. We report here that deficient PAI-1 expression in mice prevented the development of subretinal choroidal angiogenesis induced by laser photocoagulation. When systemic and local PAI-1 expression was achieved by intravenous injection of a replication-defective adenoviral vector expressing human PAI-1 cDNA, the wild-type pattern of choroidal angiogenesis was restored. These observations demonstrate the proangiogenic activity of PAI-1 not only in tumoral models, but also in choroidal experimental neovascularization sharing similarities with human AMD. They identify therefore PAI-1 as a potential target for therapeutic ocular anti-angiogenic strategies.

Aerosol gene transfer with inducible nitric oxide synthase reduces hypoxic pulmonary hypertension and pulmonary vascular remodeling in rats

BACKGROUND

Nitric oxide (NO) is a potent vasodilator with an important role in the regulation of pulmonary vascular tone. The effects of NO synthase (NOS) gene transfer on pulmonary vascular remodeling associated with hypoxic pulmonary hypertension are unknown.

METHODS AND RESULTS

We aerosolized 3 x 10(9) pfu of an adenoviral vector containing inducible NOS gene (AdNOS2), constitutive NOS3 gene (AdNOS3), or no transgene (AdRR5) into rat lungs. Exhaled NO levels, monitored with chemiluminescence, were higher in AdNOS2-infected rats than in AdNOS3- and AdRR5-infected rats (at 3 days, 33+/-6 ppb, n=9, versus 17+/-4, n=9, and 6+/-2 ppb, n=3, P:<0.05 for both). Exposure to FIO(2) 0.10 for 7 days increased pulmonary artery pressure from 19+/-4 mm Hg (baseline) to 27+/-1 and 26+/-2 mm Hg in AdNOS3- and AdRR5-infected rats, respectively, but only to 21+/-1 mm Hg in AdNOS2-infected animals (P:<0.05). After 7 days of hypoxia, total pulmonary resistance in AdRR5- and AdNOS3-infected rats was significantly higher than in AdNOS2-infected animals (0.41+/-0.05 and 0.39+/-0.07 versus 0.35+/-0. 03 mm Hg. mL(-)(1). min(-)(1), respectively, P:<0.05). Right ventricular hypertrophy was reduced in AdNOS2-infected rats [right ventricular/(left ventricular+septal) weight, 0.19+/-0.10 versus 0. 28+/-0.10 and 0.32+/-0.10 in AdRR5- and AdNOS3-infected rats, respectively, P:<0.05]. The percentage of muscularized precapillary pulmonary resistance vessels was also significantly decreased (18+/-4% versus 25+/-8% and 30+/-5% in AdRR5- and AdNOS3-infected rats, P:<0.05).

CONCLUSIONS

Aerosol NOS2 gene transfer increases pulmonary NO production and significantly reduces hypoxic pulmonary hypertension and pulmonary vascular remodeling. Aerosol NOS2 gene transfer may be a promising strategy to target pulmonary vascular disorders.

[lymphocytic colitis associated with lansoprazole treatment]

We report two cases of lymphocytic colitis with severe diarrhea in patients treated by lansoprazole for six weeks. Complete remission occurred rapidly after lansoprazole withdrawal.

Hypoxic hepatitis: a difficult diagnosis when the cardiomyopathy remains unrecognized and the course of liver enzymes follows an atypical pattern. A report of two cases

In a clinical setting of cardiac or circulatory failure, the diagnosis of hypoxic (ischaemic) hepatitis is easy and can be elicited on mere clinical and biochemical features. We report two cases of hypoxic hepatitis where cardiomyopathy remained unrecognized at admission due to the lack of conventional signs of congestive heart failure and where the increase in liver enzymes activities followed an atypical pattern, characterized by only moderate elevation of serum aminotransferases activities, low ASAT/ALAT ratio and elevated ALAT/LDH ratio. This atypical pattern not suggestive of hypoxic hepatitis, could be explained by a delay between the onset of hypoxic injury of the liver and admission to hospital. Moreover one case was complicated by frank jaundice, an unusual feature in hypoxic hepatitis. Consequently, diagnosis and appropriate inotropic treatment were delayed resulting in progressive deterioration and eventually death of both patients. The report of these two cases and the review of other similar cases previously published, enlighten some atypical features of hypoxic hepatitis.

Human endothelial nitric oxide synthase gene transfer inhibits vascular smooth muscle cell proliferation and neointima formation after balloon injury in rats

BACKGROUND

Loss of endothelial NO production after arterial injury may contribute to restenosis, characterized by neointima formation and elastic recoil. Adenovirus-mediated transfer of the gene encoding NO synthase (NOS) in balloon-injured arteries may restore NO production and inhibit neointima formation.

METHODS AND RESULTS

After balloon injury, rat carotid arteries were transduced with 3x10(10) pfu/mL recombinant adenovirus carrying the human endothelial constitutive NOS cDNA (AdCMVceNOS, n=8) or no cDNA (AdRR5, n=8). ceNOS expression was confirmed by immunoblot analysis of vascular extracts and was localized by immunostaining in 30% of medial smooth muscle cells (SMCs) and in the adventitia of AdCMVceNOS-transduced arteries. Vascular cGMP levels were reduced from 3.9 pmol/g wet wt in uninjured arteries to 0.7 pmol cGMP/g after AdRR5 but were restored after ceNOS gene transfer (3.8 pmol cGMP/g wet wt, P<.05 versus AdRR5). Intima-to-media ratio 2 weeks after injury was significantly reduced (0.19+/-0.02 in AdCMVceNOS-infected versus 0.69+/-0.07 in AdRR5-infected arteries, P<.05). In vitro, BrdU incorporation of AdCMVceNOS-infected SMCs was reduced by 28% compared with AdRR5-infected SMCs. Transduced cells from injured carotid arteries subjected to FACS sorting showed a significantly lower BrdU labeling index in ceNOS-infected rats (29+/-6% versus 43+/-5% and 45+/-4% in control, injured, and AdRR5-infected rats, respectively, P<.05).

CONCLUSIONS

AdCMVceNOS gene transfer to balloon-injured rat carotid arteries restores vascular NO production and reduces neointima formation, at least in part because of an antiproliferative effect on medial SMCs. Adenovirus-mediated ceNOS gene transfer might reduce arterial restenosis after balloon angioplasty.

Insights in vessel development and vascular disorders using targeted inactivation and transfer of vascular endothelial growth factor, the tissue factor receptor, and the plasminogen system

VEGF has been proposed to participate in normal and pathological vessel formation. Surprisingly, lack of only a single VEGF allele resulted in embryonic lethality due to abnormal formation of intra- and extra-embryonic vessels. Homozygous VEGF-deficient embryos, generated by tetraploid aggregation, revealed an even more severe defect in vessel formation. These results (1) suggest a tight regulation of early vessel development by VEGF and, indirectly, the presence of other VEGF-like molecules; (2) reveal an unprecedented lethal phenotype associated with heterozygous deficiency of an autosomal gene, and (3) demonstrate that tetraploid aggregation was a valid and the only method to study the phenotype of the homozyogous VEGF-deficient embryos. The dominant and strict dose-dependent role of VEGF in vivo renders this molecule a desirable therapeutic target for promoting or preventing angiogenesis. Tissue factor (TF) is the principal cellular initiator of coagulation and its deregulated expression has been related to thrombogenesis in sepsis, cancer, and inflammation. However, TF appears to be also involved in a variety of non-hemostatic functions including inflammation, cancer, brain function, immune response, and tumor-associated angiogenesis. Surprisingly, TF deficiency resulted in embryonic lethality due to abnormal extra-embryonic vessel development and defective vitelloembryonic circulation. The abnormal yolk sac vasculature is reminiscent of that observed in embryos lacking VEGF, possibly suggesting that both gene functions are interconnected. These targeting studies extend the recently documented role of TF in tumor-associated angiogenesis and warrant further study of its role in angiogenesis during other pathological disorders. The plasminogen system, via its triggers, tissue-type plasminogen activator (t-PA) and urokinase-type plasminogen activator (u-PA) and its inhibitor, plasminogen activator inhibitor-1 (PAI-1), has been implicated in thrombosis, arterial neointima formation, and atherosclerosis. Studies in mice with targeted gene inactivation of t-PA, u-PA, PAI-1, the urokinase receptor (u-PAR), and plasminogen (Plg) revealed (1) that deficiency of t-PA or u-PA increase the susceptibility to thrombosis associated with inflammation and that combined deficiency of t-PA:u-PA or deficiency of Plg induces severe spontaneous thrombosis; (2) that vascular injury-induced neointima formation is reduced in mice lacking u-PA-mediated plasmin proteolysis, unaltered in t-PA- or u-PAR-deficient mice and accelerated in PAI-1-deficient mice, but that it can be reverted by adenoviral PAI-1 gene transfer; and (3) that atherosclerosis in mice doubly deficient in apolipoprotein E (apoE) and PAI-1 is reduced after 10 weeks of cholesterol-rich diet. Thus, the plasminogen system significantly affects thrombosis, restenosis, and atherosclerosis.

Incidence of perforation and other mechanical complications during dual active fixation

The intraoperative and early postoperative mechanical complications of a procedure combining an atrial screw-in lead and a ventricular screw-in lead insertion were prospectively evaluated. The procedure was performed in 119 consecutive patients (mean age 69 +/- 8 years), at first implant in 100 patients and at reoperation in 19. Nine patients had previously undergone cardiac surgery and three underwent transvenous ventricular defibrillator implantation. The double sets of leads were introduced through 2 separate veins in 5 cases, through a single venous route in 114 cases, using a percutaneous approach in 75 cases and a venous cutdown in 49, and a guidewire procedure following the venotomy in 19. The screw was mannitol coated in 102 cases, exposed in 111, and extendable/retractable in 25. The fixation of the ventricular lead was performed at the apex in 108 cases, at the outflow tract in 11, and was followed by the fixation of the atrial lead at the appendage in 112 cases and at the lateral wall in 7 cases. The lead positioning and fixation were successful at first attempt in 103 cases and after repeated lead manipulation in 19 cases. The rotational torque could be transferred to the helix in all cases except in one patient who required a second vein puncture. Unintentional fixation in the ventricular chamber with subsequent failure to remove the lead occurred in one patient. Reoperation for lead dislodgment was required in two patients. In one patient, symptomatic pericarditis with pericardial effusion was observed 1 day after the procedure and resolved spontaneously. Dual active fixation is feasible with a low incidence of mechanical complications.

Compensation in a restructured environment. Part II: The past, present, and future of reward systems

The participants in the HR Consortium walked away satisfied that they had left "no stones unturned" in their efforts to create new compensation approaches. The major takeaway was that there is no ready panacea. The creation of an effective compensation system will be the development of an approach that does not serve as an obstacle to staff and managers in their efforts to build a hospital system that services customers in a restructured setting; rather it shadows and supports these operational changes.

Compensation in a patient focused environment. The past, present and future of reward systems

What have you done with compensation? It's the question asked of every healthcare organization in the midst of restructuring and work redesign. The prescription at the outset of these dramatic change programs was often for a heavy dose of compensation overhaul. But the reality has often been far less dramatic. A group of PFCA Executive Members, led by executives Mike Speer and Roger Gerard from United Health Group of Appleton, Wisconsin, were not content that the best thinking had been applied to culling out successful compensation improvements and with finding breakthrough redesign options. The group has completed the first of its brainstorming sessions in search of new approaches and offers these initial thoughts to the PFCA REVIEW readership.

[Intravenous and oral propafenone in the treatment and prevention of paroxysmal atrial fibrillation]

The efficacy of propafenone in the treatment of paroxysmal atrial fibrillation was investigated in 16 patients presenting with frequent and/or poorly tolerated paroxysmal atrial fibrillation despite prophylactic treatment in 13 patients. Prolonged atrial fibrillation (> 10 minutes) was triggered in 16 patients following a standard atrial stimulation protocol. Intravenous injection of propafenone (2 mg/kg over 5 minutes) restored sinus rhythm in 12 patients (75%) within 15 minutes after the end of the injection. In five of the 10 patients in whom this was possible, propafenone prevented the induction of atrial fibrillation in response to programmed stimulation by the same protocol. Oral propafenone (900 mg/24 hours) was indicated in 11 patients. The treatment was discontinued in 1 patient due to severe dizziness. Atrial fibrillation recurred in 4 patients 10 to 91 days after treatment began. With a mean follow-up time of 8 months, 4 patients had been brought under control and 2 had relapsed despite a generally beneficial effect. Three patients suffered side effects which did not make it necessary to stop treatment. This study suggests that intravenous propafenone is effective against persistent atrial fibrillation induced by stimulation. Oral propafenone may be useful for the prevention of attacks of recalcitrant paroxysmal atrial fibrillation.

[Wolff-Parkinson-White syndrome. Value of intravenous flecainide for detecting Kent's pathways with short refractory period]

The aim of this study was to assess the value of a non-invasive test in detecting accessory pathways with short anterograde effective refractory periods (AERP) (less than or equal to 270 ms) in patients with the Wolff-Parkinson-White syndrome. An intravenous injection of Flecainide acetate was administered to 19 consecutive patients referred for electrophysiological investigation of a WPW syndrome with permanent pre-excitation of the surface electrocardiogram. The first 8 patients (Group I) received a dose of 1.5 mg/kg over 5 minutes and the following 11 patients (Group II) were given 2 mg/kg in 5 minutes. In Group I, preexcitation disappeared in 3 patients (37.5%) who all had accessory pathways with AERP greater than 270 ms. It persisted in the other 5 patients (62.5%) of whom 4 had AERP less than or equal to 270 ms and 1 an AERP greater than 270 ms (false negative). In Group II, preexcitation disappeared in 8 patients (72.2%) of whom 4 had AERP greater than 270 ms and 4 had AERP less than 270 ms (false positives). Preexcitation persisted in the 3 other patients (27.3%); the AERP was less than or equal to 270 ms in 2 patients and greater than 270 ms in the other patients. These results suggest that intravenous Flecainide acetate at the dose of 1.5 mg/kg could be useful in differentiating WPW syndromes with long refractory periods (greater than 270 ms) from those with short refractory periods (less than or equal to 270 ms) with a satisfactory sensitivity and specificity, and that further studies on larger numbers of patients are required to confirm this hypothesis.

[Post-traumatic fistula of the left anterior descending coronary artery and left ventricle. Apropos of a new case]

The authors report the case of a 23 year old man who presented with a continuous murmur five years after closed chest trauma. The electrocardiographic and echocardiographic findings indicated previous apical myocardial infarction. The underlying diagnosis was first suggested by continuous wave Doppler which showed systolo-diastolic flow in the septo-apical region directed towards the left ventricle (LV) in diastole. Color Doppler flow studies showed a mosaic pattern opposite a dilated left anterior descending (LAD) artery. These signs of LAD-LV fistula with a single orific were confirmed at coronary arteriography. The patient's previous history was in favour of a traumatic etiology. In the absence of left ventricular failure and myocardial ischaemia by coronary steal, surgery was deferred; Doppler echocardiography would seem to be a good method of following up the fistula and its consequences on left ventricular function. A traumatic left coronary to left ventricular fistula is an extremely rare condition and merits publication. The authors review the literature and describe the physiopathology, diagnosis and therapeutic indications of these fistulae.

[Cardioversion by internal electric shock of permanent atrial fibrillation]

A new technique for cardioversion of chronic atrial fibrillation was used in 17 patients whose arrhythmia had resisted all attempts at electrical and pharmacologycal cardioversion. Atrial fibrillation was badly tolerated by all patients despite digitalis administered alone (8 patients) or combined with amiodarone (9 patients). Twelve patients had left atrial dilatation at echocardiography. The 200, 300 or 400 joule electrical shock was delivered between the proximal pole of a quadripolar catheter (cathode) and a back plate (anode). The catheter was positioned at the His bundle recording site then withdrawn into the right atrium. The internal shock restored sinus rhythm in 15 patients (88 p. 100). Transient atrioventricular block (3-315 sec) was observed in 8 patients. Eleven patients were discharged in sinus rhythm. In 4 patients, the atrial fibrillation recurred on day 8 and after 2, 4 and 9 months. A second shock was attempted in two patients and succeeded in one. After a mean follow-up period of 14.8 +/- 8 months (range 2 to 25 months), 8 of the 11 patients successfully cardioverted (72 p. 100) or of the attempted reductions (47 p. 100) were in sinus rhythm. The remaining 9 patients were treated with antiarrhythmic drugs (n = 5) or by his bundle catheter ablation (n = 4). High energy internal shock therefore seems to be an interesting treatment in patients with permanent atrial fibrillation after failure of external electric shock. It enabled 13 of the 17 patients in this series to avoid His bundle catheter ablation indicated by the quasi-impossibility to control the atrial rate and associated symptoms.(ABSTRACT TRUNCATED AT 250 WORDS)

[Atrioventricular block, a complication of radiotherapy of the mediastinum]

Cardiac complications of mediastinal irradiation usually concern the pericardium, the ventricular myocardium and the coronary arteries. We report the case of a 42-year old woman who experienced a syncopal atrioventricular (AV) block 12 years after irradiation of a mediastinal Hodgkin's lymphoma. Electrophysiological recordings showed infranodal conduction disturbances. A review of the literature yielded only 12 cases of syncopal radiation-induced AV block. This case highlights the risk of syncopal AV blocks occurring a long time after mediastinal irradiation and leading to severe damage of the His bundle and its branches. The presence, as in our patient, of an associated right ventricular outflow tract stenosis confirms the importance and severity of radiation-induced cardiac lesions.

[Anatomopathological criteria of progression in chronic idiopathic colitis]

Idiopathic inflammatory colitis are diseases of remissions and exacerbations of various severity. The criteria of activity are based on a conjunction of clinical, radiologic, endoscopic and anatomopathological data. From the macroscopical point of view, they are different in ulcerative colitis and Crohn's disease. Ulcerative colitis is characterized by a diffuse and uniform mucosal inflammation; any biopsy outside an ulcerative area can be used to evaluate the inflammatory components which are in the acute phase (chronic active phase): oedema, vascular congestion and an inflammatory infiltrate composed of a mixture of lymphocytes, plasma cells and polymorphs with partial destruction of the glands (crypt abscesses). In the revolving phase, the inflammation regresses; the crypts are distorted, the crypt abscesses gradually disappear. In ulcerative colitis in remission, the inflammation vanishes but there is loss of parallelism and branching of the crypts. In Crohn's disease, the inflammation is often discontinuous and focal; biopsies must be taken from multiple sites. It is not rare to see a coincidence of lesions at different stages of activity. The criteria of activity are less reliable than in ulcerative colitis. Acute lesions present with oedema and infiltration of the lamina propria by polymorphs, neutrophils as well as eosinophils. Granulomas probably represent a particular reactional status. There features and number do not very significatively in the course of the disease.

The single-chain form of tissue-type plasminogen activator has catalytic activity: studies with a mutant enzyme that lacks the cleavage site

Tissue-type plasminogen activator (t-PA), the serine protease responsible for catalyzing the production of plasmin from plasminogen at the site of blood clots, is synthesized as a single-chain polypeptide precursor. Proteolytic cleavage at the C-terminal side of Arg275 generates a two-chain form of the enzyme whose subunits are held together by a single disulfide bond. We have measured the activities of both forms of the wild-type enzyme, as well as that of a mutant enzyme (Arg275----Gly), created by oligonucleotide-directed mutagenesis, that cannot be cleaved into a two-chain form. Both types of single-chain t-PAs are enzymatically active and exhibit identical Vmax and Km values when assayed with synthetic peptide substrates, indicating that the single amino acid change had no effect on the amidolytic activity of the enzyme. However, cleavage of wild-type t-PA into the two-chain form results in increased activity both on a peptide substrate and on the natural substrates Lys- and Glu-plasminogen in the absence or presence of stimulation by soluble fibrin. The enhanced activity is due to a 3-5-fold increase in the Vmax of the cleaved enzyme, rather than to any change in the Km values for the various substrates. During incubation with plasminogen, the single-chain form of wild-type t-PA is converted to the two-chain form by plasmin generated during the reaction. This conversion, from the less active form of the enzyme, results in a reaction that displays biphasic kinetics.(ABSTRACT TRUNCATED AT 250 WORDS)

Asymptomatic form of left pulmonary artery sling

Eight patients with left pulmonary artery sling, which were asymptomatic at the time of the last consultation, are described: 2 adults and 1 child with no history of symptoms, 3 children with mild forms of airways obstruction and 2 patients with typical severe symptoms of airways obstruction in infancy. The mean follow-up of these 8 patients was 10 years (range 4 to 23), and in 1986, all were in good health and free of respiratory symptoms. The long-term prognosis is usually good.

Tissue plasminogen activator: from molecular biology to myocardial infarction

The recent development of recombinant tissue plasminogen activator as a therapeutic agent during acute myocardial infarction is one of the most lucid examples of the potential impact of recombinant DNA technology in clinical medicine. This remarkable achievement would not have been possible without several key discoveries in molecular biology and clinical cardiology and exemplifies the synergistic relationship between basic and clinical research. This article chronicles this journey from molecular biology to myocardial infarction.

Functional analysis of the role of the A + T-rich region and upstream flanking sequences in simian virus 40 DNA replication

One boundary of the minimal origin of replication of simian virus 40 DNA lies within the A + T-rich region. Deletion of only a few bases into the adenine-thymine (AT) stretch results in a DNA template which is defective for replication both in vivo and in vitro (B. Stillman, R. D. Gerard, R. A. Guggenheimer, and Y. Gluzman, EMBO J. 4:2933-2939, 1985). In the present study, such deletion mutations have been reconstructed into a simian virus 40 genome containing an intact early promoter-enhancer region. The resulting mutants synthesized wild-type levels of T antigen, but were defective for replication and would not form plaques on CV-1 monkey cells. Replication-competent phenotypic revertants were selected after transfection of large quantities of the replication-defective viral DNAs into CV-1 cells. DNA sequence analysis showed that most of these revertants contained insertions or point mutations which partially regenerate the length of the AT stretch. These genotypic alterations were shown to be responsible for the revertant phenotype by replication analysis in vivo of subcloned revertant origin fragments. In general, our results emphasize the importance of the AT region to simian virus 40 origin function. However, one revertant retained the altered AT region but deleted six nucleotides upstream. Experiments using this mutant indicate that the 21-base-pair repeats identified as part of the early transcriptional promoter may compensate for defects in simian virus 40 DNA replication in vivo caused by mutations in the A + T-rich region when positioned at an appropriate distance from the core origin.

Alternate ventriculo-atrial Wenckebach conduction during ventricular tachycardia

Although pacing-induced ventriculo-atrial (VA) Wenckebach conduction has been previously described, the occurrence of this phenomenon during ventricular tachycardia has received little attention. The latter is defined as 2:1 VA block in which the conducted beats show progressive lengthening of VA conduction until the sequence is terminated by two or three blocked ventricular beats. This phenomenon was observed in a 16-year-old boy who underwent electrophysiologic study for ventricular tachycardia as a late complication of surgical correction of tetralogy of Fallot. During pacing-induced ventricular tachycardia with a morphology similar to that of the spontaneous tachycardia, 8:4 alternating VA block was observed. This sequence suggested that the AV node was the site of block, the 2:1 block being located at the upper level, and the VA Wenckebach block at the lower level. Alternate VA Wenckebach conduction appears as a possible cause of variation in atrial depolarization intervals during ventricular tachycardias with short cycle lengths.

Bepridil for recurrent sustained ventricular tachycardias: assessment using electrophysiologic testing

Bepridil was found to possess electrophysiologic properties common to class I and IV antiarrhythmic agents. Intravenous and oral bepridil were evaluated using serial electrophysiologic studies in a selected group of 9 patients with recurrent sustained ventricular tachycardia (VT) unresponsive to usual therapy, including amiodarone therapy in 15 patients. Intravenous bepridil treatment terminated sustained, well tolerated, pacing-induced VT in 3 of 6 patients and prevented the initiation of VT in 2 of these and in a patient in whom the drug failed to restore sinus rhythm. Oral bepridil was administered at a loading dose of 800 mg on day 1, and 500 to 600 mg the following days, and programmed electrical stimulation was repeated 2 to 6 days after initial study. Oral bepridil therapy prevented VT initiation in 6 patients (66%). The tachycardia cycle length was prolonged (30 to 105 ms) in 2 patients in whom VT remained inducible. In 1 patient the tachycardia cycle length significantly shortened after bepridil and prompt cardioversion was required. Five of the 6 patients with successful results underwent long-term oral treatment with bepridil. VT recurred in 1 patient during the hospitalization period and an adverse effect (paralytic ileus) in another patient required drug discontinuation. Three patients remain symptom-free over a follow-up of 4 to 13 months. These data suggest that bepridil may be useful in patients with recurrent, sustained VT.

Bidirectional tachycardia. Mechanism derived from intracardiac recordings and programmed electrical stimulation

His bundle recordings and programmed electrical stimulation were performed in a 70-year-old woman with bidirectional tachycardia; the recordings demonstrated the infra-Hissian origin of the tachycardia. Occurrence of the His deflection slightly after the onset of ventricular depOlarization suggested that the origin of the tachycardia was located near the His bundle bifurcation. Recording of three atrial sites during tachycardia allowed the study of retrograde atrial activation. Two sets of fairly constant and alternating VA intervals were recorded. This fact is consistent with two ventricular circuits used alternatively. The tachycardia could also be interrupted with a single atrial or ventricular premature beat. It is postulated that the tachycardia is due to macroreentry involving the two fascicles of the left branch. This study suggests that reentry may be a possible mechanism in some cases of bidirectional tachycardia.

Long-term results of permanent atrioventricular sequential demand pacing

Pervenous atrioventricular sequential demand pacemakers (AVSDPs) were implanted in 18 patients using an atrial electrode positioned in the right atrial appendage and a ventricular electrode positioned at the apex of the right ventricle. The indications included 13 patients with the sick sinus syndrome (72%), five of whom had the tachycardia-bradycardia syndrome, three with paroxysmal supraventricular tachycardia, one with cardiomyopathy and one with carotid sinus syncope. The follow-up ranged from 6 to 38 months, with a mean of 19.4 months (a total of 350 pacing months). Seventeen patients (94%) are asymptomatic. One patient had persistent episodes of paroxysmal supraventricular tachycardia. In the remaining patients with tachyarrhythmia, pacing alone (three patients) or in combination with antiarrhythmic drugs (four patients) controlled the tachyarrhythmia. There was one displacement of the atrial electrode (5.5%). Extrusion of the pacer occurred in three patients. It is concluded from this experience that AV sequential pacing is an effective technique and may be useful in patients with sick sinus syndrome, in patients with tachyarrhythmia and/or patients with poor myocardial function. However, continued research is needed to prolong battery life and to reduce the size of the pacemaker.

[Coronary insufficiency in the female: possible effect of menopause]

A population of 239 women suffering from chronic coronary disease was divided into two groups according to whether or not they had sustained a myocardial infarction. For the 226 post-menopausal women, the type of menopause (natural or artificial) and their age at its onset were determined, together with the age of onset of the infarction or angina, and possible correlations with other risk factors in atherosclerosis. Whilst the average age at the time of artificial menopause was markedly less than that of natural menopause, the age of onset of coronary complications was comparable regardless of the type of menopause, this applying to both groups. Contrary to a classically accepted opinion, early menopause would not appear to favourise the premature development of atherosclerotic coronary problems, and, in addition, would not appear to affect other coronary "risk factors".