Conservation of hepatitis C virus nonstructural protein 3 amino acid sequence in viral isolates during liver transplantation.

As a consequence of selective pressure exerted by the immune response during hepatitis C virus (HCV) infection, a high rate of nucleotide mutations in the viral genome is observed which leads to the emergence of viral escape mutants. The aim of this study was to evaluate the evolution of the amino acid (aa) sequence of the HCV nonstructural protein 3 (NS3) in viral isolates after liver transplantation. Six patients with HCV-induced liver disease undergoing liver transplantation (LT) were followed up for sequence analysis. Hepatitis C recurrence was observed in all patients after LT. The rate of synonymous (dS) nucleotide substitutions was much higher than that of nonsynonymous (dN) ones in the NS3 encoding region. The high values of the dS/dN ratios suggest no sustained adaptive evolution selection pressure and, therefore, absence of specific NS3 viral populations. Clinical genotype assignments were supported by phylogenetic analysis. Serial samples from each patient showed lower mean nucleotide genetic distance when compared with samples of the same HCV genotype and subtype. The NS3 samples studied had an N-terminal aa sequence with several differences as compared with reference ones, mainly in genotype 1b-infected patients. After LT, as compared with the sequences before, a few reverted aa substitutions and several established aa substitutions were observed at the N-terminal of NS3. Sites described to be involved in important functions of NS3, notably those of the catalytic triad and zinc binding, remained unaltered in terms of aa sequence. Rare or frequent aa substitutions occurred indiscriminately in different positions. Several cytotoxic T lymphocyte epitopes described for HCV were present in our 1b samples. Nevertheless, the deduced secondary structure of the NS3 protease showed a few alterations in samples from genotype 3a patients, but none were seen in 1b cases. Our data, obtained from patients under important selective pressure during LT, show that the NS3 protease remains well conserved, mainly in HCV 3a patients. It reinforces its potential use as an antigenic candidate for further studies aiming at the development of a protective immune response.

Transluminal angioplasty for renovascular hypertension complicated by pregnancy.

Percutaneous transluminal angioplasty was successfully used in the treatment of renovascular hypertension that resulted from fibromuscular hyperplasia in a 26-year-old woman who was four weeks' pregnant. The patient's BP normalized immediately. She had a normal pregnancy that terminated in the delivery of a full-term normal child. Two and a half years after the procedure, she remained normotensive without taking antihypertensive medication. Percutaneous transluminal angioplasty may be useful in the treatment of renal artery stenosis complicated by hypertension and pregnancy, where the inherent risk of toxemia endangers the life of the mother and fetus.

Episodic confusion and tremor associated with extrahepatic portacaval shunting in cirrhotic liver disease.

In an elderly male patient with alcohol-related liver disease, who developed episodic confusion and tremor, we found a large extrahepatic portacaval shunt. He had no clinical or laboratory evidence of liver dysfunction except for an elevated serum ammonia level that increased further in response to an ammonium chloride challenge test. Extrahepatic portacaval shunting causing episodic confusion and tremor may occur with alcoholic liver disease without overt liver failure and may require abdominal angiography or a transhepatic portogram to demonstrate the shunt.

Abnormal captopril renogram with a technetium-99m-labeled hippuran analog.

A case of renovascular hypertension is presented in which the [131I]hippuran renogram was initially normal, but became strikingly abnormal upon administration of the angiotensin converting enzyme (ACE) inhibitor captopril. The patient presented with fibromuscular dysplasia of the renal arteries, which was shown by hippuran renography to be functionally significant on the right side. She became normotensive after angioplasty of the right renal artery. Hypertension recurred a year later, at which time the renogram was normal without captopril, but showed functionally significant left renal artery stenosis with captopril challenge. Both the conventional agent, [131I]hippuran, and an experimental new 99mTc-labeled hippuran analog, [99mTc]MAG3, were used. Angiography confirmed progression of disease on the left side, which was successfully treated by angioplasty. Functionally significant unilateral renal artery stenosis was thus demonstrated first on the right side and then, 1 yr later, on the left side, using hippuran and [99mTc]MAG3. Anatomic progression of disease was documented by angiography.

Osler-Weber-Rendu disease and pulmonary arteriovenous fistulas. Deterioration and embolotherapy during pregnancy.

Several reports have implicated pregnancy as a cause of deterioration in patients with pulmonary arteriovenous fistulas. We report a 27-year-old woman with multiple pulmonary arteriovenous fistulas who required coil spring embolotherapy in her 24th week of pregnancy due to a spontaneous hemothorax and hypoxemia.

Percutaneous interventional catheter therapy for lesions of the chest and lungs.

Percutaneous, nonsurgical interventions using angiographic catheter techniques and radiologic guidance were used in the management of seven cases of various lesions of the chest and lungs. Successful catheter therapy included the embolization of a large, acquired, postinflammatory vascular malformation causing massive hemoptysis and a cavernous hemangioma of the chest wall. Sixteen pulmonary arteriovenous fistulas (one patient), an iatrogenic internal mammary artery-to-innominate vein fistula, and a persistent, postbiopsy bronchopleural fistula were successfully closed. Percutaneous drainage of a pyogenic lung abscess and the nonoperative retrieval of an intravascular foreign body that had embolized to the left pulmonary artery were also successfully achieved. Performed under local anesthesia with minimal morbidity, stress, and risk, interventional catheter therapy is remarkably cost-effective. Primary chest physicians are encouraged to consider this mode of therapy whenever applicable.

Retrograde pancreatic venography after reduction of the arterial visceral flow: an experimental study.

To evaluate techniques for retrograde pancreatic venography similar to epinephrine renal venography, 35 dogs had transjugular portography before and after the infusion of various doses of vasopressin systemically or selectively into the superior mesenteric and celiac arteries, or after occlusion of the distal thoracic aorta. Increased filling of the peripheral portal branches resulted, but none of the techniques provided diagnostically useful enhanced pancreatic visualization.

Percutaneous angiographic embolization: a procedure of increasing usefulness: review of a decade of experience.

During the past decade percutaneous therapeutic vascular occlusion was performed on 152 occasions in 124 patients. The primary indication for vasoocclusive therapy was acute or recurrent bleeding. Upper gastrointestinal bleeding from arterial sources was controlled in 92 percent of patients and acute variceal bleeding in 83 percent. Renal embolization was performed for palliation of severe pain and hematuria from unresectable renal primary or secondary malignancies, to decrease blood loss and facilitate surgery in operable renal tumors, and for ablation of renal function to control chronic protein loss or severe hypertension. Our encouraging experience convinces us that transcatheter embolization is a useful, safe and effective procedure in selected patients. It seems certain that the technique of therapeutic embolization will be improved, its indications extended and its application become commonplace whenever angiographic skills and facilities exist.

Hepatic allograft abscess with hepatic arterial thrombosis.

BACKGROUND: Intrahepatic abscess (IA) is an uncommon complication after liver transplantation (OLTx) usually found in the setting of hepatic arterial thrombosis (HAT) often with associated biliary tree necrosis and/or stricture. Conventional treatment of IA in this setting has required retransplantation. METHODS: A retrospective review of 274 patients (287 OLTx) from September 1991 through September 1996 was performed. Median follow-up was 3.6 years. Diagnosis of HAT was confirmed by arteriography and IA was documented by computerized tomography. Percutaneous drainage of the abscess and stenting of biliary strictures, if present, was achieved using conventional interventional radiology techniques. RESULTS: The diagnosis of hepatic artery complication was made in 14 patients (5.1%), 2 of whom required retransplantation. Hepatic artery thrombosis associated with solitary IA was found in 3 patients (1%) who were transplanted in our center and in 1 additional patient followed up at our center but transplanted elsewhere. All 4 patients had complete resolution of IA using this approach. Three of the 4 patients are alive and well, with the fourth patient succumbing to recurrent hepatitis B infection resulting in allograft failure. CONCLUSIONS: Solitary hepatic allograft abscesses associated with HAT respond to percutaneous drainage and antibiotics, obviating the need for retransplantation in this setting.

Angiographic evaluation and management of nonvariceal upper gastrointestinal bleeding.

Endoscopy is the primary diagnostic and therapeutic tool used in the evaluation and treatment of patients with upper gastrointestinal bleeding. When endoscopy is unsuccessful in identifying or controlling GI hemorrhage, however, arteriography is useful in both the evaluation and treatment of upper GI hemorrhage.

Percutaneous management of iatrogenic arterial venous fistulas by coil spring occlusion.

Six patients with iatrogenic arterial venous fistulas (AVFs) underwent successful transcatheter occlusion with coil springs. Three patients had AVFs as complications of surgery and in two other patients the AVFs were due to insertion of the central venous catheters. One iatrogenic AVF occurred following transhepatic obliteration of gastroesophageal varices. Management of iatrogenic AVFs by transcatheter occlusion avoids additional surgery and reduces morbidity and hospital costs. Coil springs are highly suitable for occluding iatrogenic arterial venous fistulas. They need no special preparation, are readily available, inexpensive, and easy to use.

Treatment of hemobilia by transcatheter vascular occlusion.

Four cases of hemobilia treated by transcatheter arterial occlusion are presented and reviewed with 30 similar cases reported in the literature. Transcatheter vascular occlusion successfully controlled hemorrhage in all 34 patients. No obvious liver parenchymal damage appeared in 26 patients; transient elevation of liver enzymes occurred in 6 patients (18%) including one in our series; two of the patients reviewed died of acute hepatic insufficiency following nonselective hepatic artery embolization. Hemobilia should be considered when gastrointestinal hemorrhage occurs after abdominal trauma, liver biopsy or other manipulative liver procedures. Hepatic angiography establishes the diagnosis and selective vascular occlusion is the treatment of choice for control of intractable or recurrent hemorrhage. Techniques and precautions for the diagnosis and transcatheter therapy of hemobilia are discussed.

Anatomical vs "Functional" left ventricular aneurysm: angiographic differentiation and management implication.

Accurate diagnosis of the type of the left ventricular aneurysm (LVA) is essential for selection of appropriate surgical therapy. To assess the efficacy of angiography including conventional and dynamic ventriculography and coronary angiography in determining the LVA nature, 41 consecutive patients with various types of LVA, proven by surgery or autopsy, were evaluated. In all 22 patients with a "true", anatomical LVA, the angiographic diagnosis was correct. Nineteen patients had a "functional" LVA. In 16 of them studied by all three methods, the determination of the underlying pathologic process in the regions of wall motion abnormalities was correct; it corresponded to the findings at surgery in 15 patients, at autopsy in 1 patient, and also to follow-up angiographic studies in 12 patients. False diagnoses of an anatomical LVA were made at the beginning of the series in 3 patients in whom dynamic ventriculography was not used. On the basis of reported experience and review of the literature, findings important for differential diagnosis of individual lesions are emphasized. It is concluded, that a comprehensive evaluation of conventional left ventriculography complemented when necessary by dynamic ventriculography, together with coronary angiography, enables an accurate diagnosis in most cases. It is suggested that the term LVA be used for an anatomical aneurysm only; in patients with "functional" LVA an attempt should be made to determine the nature of the underlying processes, in particular to differentiate reversible from irreversible wall motion abnormalities.

Interventional angiography in the diagnosis of acute lower gastrointestinal bleeding.

Interventional angiography with the use of indwelling arterial catheters, anticoagulants, vasodilators and fibrinolytic agents, complements conventional angiography in the diagnosis of acute lower gastrointestinal bleeding. These interventional techniques prolong, augment or reactive bleeding and, by enabling better timing of examinations, they increase the diagnostic efficacy of angiography. In the reported series of 63 patients with acute lower gastrointestinal hemorrhage, interventions increased the diagnostic yield of angiography for demonstration of extravasation from 32% to 65% and decreased the percentage of negative angiograms from 27% to 16%. Indications, techniques and risks of interventional angiography in the diagnosis of acute lower gastrointestinal bleeding are discussed.

Acquired diseases of aberrant subclavian arteries.

The anatomic, clinical, and radiologic findings of aberrant subclavian arteries (ASAs) are well known. Acquired diseases such as aneurysms, dissections, or stenosis can complicate these anomalies. We propose that these complications are a result of atherosclerosis caused by abnormal turbulence around the ASA. Comparisons of computed tomographic and angiographic measurements of subclavian arteries in adults with and without arch anomalies and angiographic measurements of ASAs in children show that ASAs dilate in older patients. We describe six patients with acquired diseases of ASAs or the aorta adjacent to the ASA. Aneurysms, aortic dissections, and stenosis were each found in two patients. Problems in the radiologic diagnosis and clinical management of these diseases are emphasized. Radiologists should be cognizant of the significance of ASAs in patients with aortic aneurysms and dissections.

Transcatheter embolization of a high-flow congenital intrahepatic arterial-portal venous malformation in an infant.

An intrahepatic arterial-portal venous malformation (APVM) was diagnosed in a 4 1/2-month-old infant with portal hypertension. Visceral angiography showed a large saccular vascular space in the left hepatic lobe with a multiplicity of feeding arteries and drainage into the left portal vein. The lesion was successfully treated by transcatheter embolization following two unsuccessful surgical procedures. Two years later portal vein thrombosis with cavernous transformation was diagnosed, possibly a consequence of the high-flow arterial-portal shunt and its subsequent occlusion. Knowledge of the anatomic differences between this rare congenital APVM and the more commonly occurring arterial-portal fistula is crucial in planning effective transcatheter embolotherapy or surgery for these lesions.

Aortic and venous valve for percutaneous insertion.

The purpose of this paper is to present in vitro and in vivo experimental evaluation of a new, artificial, bicuspid, aortic and venous valve. Valves were constructed from square stents with barbs covered by porcine small intestine submucosa (SIS). A valve 15 mm in diameter was tested in a flow model (2.5 l/min) with pressure measurement. A 100-ml rubber bag attached to a side arm of the flow model simulated heart ejection fraction. In acute (n=6) and short-term (n=3) experiments conducted in four swine and four dogs, valves ranging from 16-28 mm in diameter were placed into the ascending aorta through 10 F sheaths; three were placed subcoronary and six in a supracoronary position. Function and stability of the valves were studied with pressure measurements and aortograms. Three short-term animals were sacrificed for gross and histologic evaluation at one, two and four weeks respectively. In an acute experiment, venous valves with four barbs were placed into the IVC through an 8 F guiding catheter in three dogs. For longer-term testing, valves were placed into the IVCs and iliac veins of three young swine. The animals were followed up after two weeks with venograms, then were sacrificed for gross and histologic evaluation.

Reverse endoventricular artificial obturator in tricuspid valve position. Experimental feasibility research study.

The concept of vena contracta space reduction in tricuspid valve position was tested in an animal model. Feasibility of specific artificial obturator body (REMOT) fixed to the right ventricular apex and interacting with tricuspid valve leaflets was evaluated in three different animal studies. Catheter-based technique was used in three series of experiment in 7 sheep. First acute study was designed for evaluation if the screwing mode of guide wire anchoring to the right ventricular apex is feasible for the whole REMOT body fixing. Longer study was aimed to evaluate stability of the REMOT body in desired position when fixing the screwing wire on its both ends (to the right ventricular apex and to the skin in the neck area). X-ray methods and various morphological methods were used. The third acute study was intended to the REMOT body deployment without any fixing wire. In all of 7 sheep the REMOT was successfully inserted into the right heart cavities and then fixed to the right ventricular apex area. When the REMOT was left in situ more than 6 months it was stable, induced adhesion to the tricuspid valve leaflet and was associated with a specific cell invasion. Releasing of the REMOT from the guiding tools was also successfully verified. Deployment of the obturator body in the aim to reduce the tricuspid valve orifice is feasible and well tolerated in the short and longer term animal model. Specific cell colonization including neovascularization of the obturator body was observed.