Diagnostic value of the electrocardiogram in suspected pulmonary embolism.

The electrocardiogram is shown to be of limited diagnostic value for determining pulmonary embolism in a prospective cohort study of unselected patients with suspected pulmonary embolism.

Upper extremity deep venous thrombosis. Underdiagnosed and potentially lethal.

The significance of upper extremity deep venous thrombosis (DVT) has been minimized in comparison to iliofemoral thrombosis, likely due to the erroneous belief that subsequent pulmonary thromboembolism is rare. The possibility of pulmonary thromboembolism originating in the upper extremity veins must now be seriously considered with catheters and medical instrumentation being performed more commonly in accessing the central venous system. It has been incorrectly assumed that the risk of pulmonary embolism was low due to the abundant collateral flow, and thus lack of stasis around an upper extremity even with venous occlusion. However, several studies, including a recent prospective trial, concluded that pulmonary embolism is not a rare complication in upper extremity DVT. Significantly, when comparing all sources of secondary upper extremity DVT, catheter-related upper extremity DVT is at greatest risk of subsequent pulmonary thromboembolism. We present an illustrative case documenting extensive pulmonary embolization that occurred following insertion of a central venous catheter and subsequent thrombosis of the right subclavian and innominate veins. With absolute contraindications to thrombolytic and anticoagulation therapy, prevention of further embolization was achieved by percutaneous insertion of a superior vena cava filter.

Steady-state end-tidal alveolar dead space fraction and D-dimer: bedside tests to exclude pulmonary embolism.

STUDY OBJECTIVE: Less than 35% of patients suspected of having pulmonary embolism (PE) actually have PE. Safe bedside methods to exclude PE could save health-care resources and improve access to diagnostic testing for suspected PE. In patients with suspected PE, we sought to determine the sensitivity, specificity, and negative predictive value of (1) a steady-state end-tidal alveolar dead space fraction (AVDSf) of < 0.15, (2) a negative D-dimer result, and (3) the combination of a steady-state end-tidal AVDSf of < 0.15 and a negative D-dimer result. STUDY DESIGN: Prospective cohort study. SETTING: Tertiary-care center in Ottawa, Ontario, Canada. PATIENTS: Consecutive inpatients, outpatients, and emergency department patients with suspected PE referred to the Departments of Nuclear Medicine or Radiology for investigation of suspected PE. INTERVENTIONS AND MEASUREMENTS: All study patients had D-Dimer and alveolar dead space measurements prior to determining outcome (PE or no PE) with ventilation/perfusion scans and/or noninvasive leg vein imaging and/or pulmonary angiography. RESULTS: Two hundred forty-six eligible and consenting patients underwent diagnostic imaging that excluded PE in 163 patients, diagnosed PE in 49 patients, and was indeterminant in 34 patients. A negative D-dimer result excluded PE with a sensitivity of 83.0% (95% confidence interval [CI], 69.2 to 92.4%), a negative predictive value of 91.2% (95% CI, 83.4 to 96.1%), and a specificity of 57.6%. A steady-state end-tidal AVDSf of < 0.15 excluded PE with a sensitivity of 79.5% (95% CI, 63.5 to 90.7%), a negative predictive value of 90.7% (95% CI, 82.5 to 95.9%), and a specificity of 70.3%. The combination of a negative D-dimer result and a steady-state end-tidal AVDSf of < 0.15 excluded PE with a sensitivity of 97.8% (95% CI, 88.5 to 99.9%), a negative predictive value of 98.0% (95% CI, 89.4 to 99.9%), and a specificity of 38.0%. CONCLUSION: This simple combination of bedside tests may safely rule out PE without further diagnostic testing in large numbers of patients with suspected PE.

High-flow priapism associated with Fabry's disease in a child: a case report and review of the literature.

We report a case of priapism in an 11-year-old boy known to have Fabry's disease. High flow was confirmed by color flow Doppler ultrasound and intracorporal blood gas measurements. Successful treatment was achieved by unilateral percutaneous Gelfoam embolization of the left internal pudendal artery. Previously reported cases of priapism associated with Fabry's disease were identified through a MEDLINE search of the English literature and review of the publications. Five reported cases of priapism associated with Fabry's disease were found, including those of 3 children. A report of a child with high-flow priapism that did not respond to conventional treatment including cavernovenous shunting was noted. Priapsim associated with Fabry's disease may be caused by unregulated high arterial inflow. Early recognition of the underlying pathophysiology may identify those cases that would be amenable to percutaneous embolization therapy and may obviate the need to pursue other ineffective conventional treatments.

Definitive treatment of focal nodular hyperplasia of the liver by ethanol embolization.

Focal nodular hyperplasia (FNH) is a benign, usually asymptomatic liver tumor with no predisposition to spontaneous hemorrhage. Treatment is not mandatory unless large size, compression symptoms, or fear of traumatic hemorrhage indicate otherwise. Ethanol embolotherapy offers a safe and effective alternative to surgery. FNH lends itself particularly well to embolotherapy because it is usually fed by a single end-artery with no intratumoral arteriovenous shunting or parasitic blood supply. An illustrative case is presented. Diagnosis was established by ultrasound, computed tomography (CT) scan, radionuclide scan, and arteriography and was confirmed by biopsy. Ethanol embolization resulted in shrinkage of a 10 x 14 cm tumor to a 1.5-cm calcified nodule over an 18-month period.

Primary aortogastric fistula: a complication of ruptured aortic aneurysm.

An aortogastric fistula which resulted from rupture of an atherosclerotic aneurysm of the descending and supraceliac aortic segments is reported. The diagnosis was suspected preoperatively on the basis of CT and angiographic examinations. Vascular replacement was accomplished without difficulty, but a fatal outcome eventually occurred because of failure of local repair of the gastric defect. Relevant literature on primary aortoenteric fistulas has been reviewed, with particular emphasis on reports detailing management of the alimentary tract perforations. We now believe that resection should be strongly considered in situations where both resection and local repair of the enteric defect are options.

[Treatment of cancer of the bladder in elderly patients with an intra-arterial chemotherapy and radiotherapy combination: 10-year experience]. / Traitement du cancer de la vessie chez les patients âgés par association de chimiothérapie intra-artérielle et de radiothérapie: 10 ans d'expérience.

PURPOSE: Analysis of the results obtained in elderly (75 years and older) included a phase II trial combining intra-arterial cisplatin and concurrent radiation into invasive bladder cancer. PATIENTS AND METHODS: Thirty-five patients (28 males and 7 females) were accrued from 1985 to 1996. There were 1 Ta, 4 T2, 11 T3A, 12 T3B, 3 T4A, and 4 T4B patients. Nine had unilateral hydronephrosis and two bilateral hydronephrosis. There were 28 transurethral resections which were incomplete in 23 patients. Intra-arterial cisplatin was given as 2-4 hours infusion (60-90 mg/m2) split through both internal iliac arteries on day 1, 14, 21, and 42. Irradiation to the pelvis was started on day 14 and consisted of 40 Gy/20 fractions followed by a boost of 20 Gy/10 fractions to the tumor with margins of 2 cm. RESULTS: Thirty (86%) completed fully the protocol. One patient died from sepsis secondary to the treatment. The tumor response was evaluable in 29 patients and complete response was observed for 27 of them. Five of these 27 patients had an isolated bladder relapse which was salvaged by cystectomy in two patients. There were 11 deaths from bladder cancer (31% of the patients): 9 from distant metastase, one from local failure, and one from treatment. CONCLUSION: This combined modality yields excellent results with high complete response rate and good tolerance. This approach may therefore be particularly appropriate for the elderly.

Multidisciplinary Canadian consensus recommendations for the management and treatment of hepatocellular carcinoma.

Globally, hepatocellular carcinoma (hcc) is the third most common cause of death from cancer, after lung and stomach cancer. The incidence of hcc in Canada is increasing and is expected to continue to increase over the next decade. Given the high mortality rate associated with hcc, steps are required to mitigate the impact of the disease. To address this challenging situation, a panel of 17 hcc experts, representing gastroenterologists, hepatologists, hepatobiliary surgeons, medical oncologists, pathologists, and radiologists from across Canada, convened to provide a framework that, using an evidence-based approach, will assist clinicians in optimizing the management and treatment of hcc. The recommendations, summarized here, were developed based on a rigorous methodology in a pre-specified process that was overseen by the steering committee. Specific topics were identified by the steering committee and delegated to a group of content experts within the expert panel, who then systematically reviewed the literature on that topic and drafted the related content and recommendations. The set of recommendations for each topic were reviewed and assigned a level of evidence and grade according to the levels of evidence set out by the Centre for Evidence-based Medicine, Oxford, United Kingdom. Agreement on the level of evidence for each recommendation was achieved by consensus. Consensus was defined as agreement by a two-thirds majority of the 17 members of the expert panel. Recommendations were subject to iterative review and modification by the expert panel until consensus could be achieved.

Gastroduodenal artery aneurysm: treatment by transcatheter embolization.

Aneurysm of the gastroduodenal artery is a rare but well recognized complication of acute and chronic pancreatitis. It appears to be secondary to the proteolytic action of activated pancreatic enzymes on the arterial wall. A case is reported of massive, life-threatening hemorrhage in a patient with a gastroduodenal artery aneurysm. The aneurysm was diagnosed by angiography and treated by embolization with Gianturco coils, the first successful use of this technique. A review of the literature revealed that bleeding in the upper gastrointestinal tract is a very common clinical presentation and is frequently fatal. Arteriography followed by computerized tomography are the most specific modalities of diagnosis.

Metformin and contrast media: where is the conflict?

Intravascular administration of iodinated contrast media to patients who are receiving metformin, an oral antidiabetic agent, can result in lactic acidosis. However, this rare complication occurs only if the contrast medium causes renal failure, and the patient continues to take metformin in the presence of renal failure. Because metformin is excreted primarily by the kidneys, continued intake of metformin after the onset of renal failure results in a toxic accumulation of this drug and subsequent lactic acidosis. To avoid this complication, metformin must be withheld after the administration of the contrast agent for 48 hours, during which the contrast-induced renal failure becomes clinically apparent. If renal function is normal at 48 hours, the metformin can be restarted. There is no scientific justification for withholding metformin for 48 hours before administration of the contrast medium, as currently recommended in the package insert. The authors review the pharmacology of metformin and present a departmental policy for managing patients with diabetes who receive metformin and who require intravascular administration of iodinated contrast media.

Anticoagulant effects of contrast materials: in vitro study of iohexol, ioxaglate, and diatrizoate.

It has been reported that clot formation may occur when blood is mixed directly with nonionic contrast medium in a syringe during angiography. To investigate this possibility, we performed three in vitro experiments to determine the anticoagulant properties of a low-osmolar, nonionic contrast medium (iohexol); a low-osmolar, ionic medium (ioxaglate); and a high-osmolar, ionic medium (diatrizoate). In the first experiment, human arterial blood was incubated at room temperature in an angiographic syringe with each of the three media for 60 min, after which the mixture was filtered for clots. In the second experiment, the clotting times of venous blood in heparinized saline or serial dilutions of the three agents were determined. In the third experiment, the partial thromboplastin time of platelet-poor plasma in heparinized saline or serial dilutions of the three agents was measured. No clots were observed in any of the arterial blood samples. Iohexol prolonged the normal 15-min clotting time of venous blood to 160 min, compared with a clotting time of at least 330 min for ioxaglate and diatrizoate. Iohexol prolonged the normal 36-sec partial thromboplastin time of platelet-poor plasma to 40 sec, compared with 50 sec for diatrizoate and 54 sec for ioxaglate. Our data show that iohexol, like ioxaglate and diatrizoate, inhibits clot formation when mixed with blood in a syringe. It prolongs the clotting time to approximately the same degree as 600 U/l of heparinized saline, but to a lesser degree than the other two media. All three media have a minimal effect on the partial thromboplastin time. Our results do not show any risk of clot formation in the usual clinical setting in which there is inadvertent mixing of blood with iohexol, ioxaglate, or diatrizoate in an angiographic syringe.

Caliber-persistent artery of the stomach (Dieulafoy's vascular malformation).

Caliber-persistent artery of the stomach (also known as cirsoid aneurysm, Dieulafoy's lesion, and submucosal arterial malformation) is clinically manifested as recurrent, massive, often fatal hematemesis. The lesion often is not seen endoscopically. Left gastric angiography in one patient with hematemesis showed a convoluted and ectatic artery in the gastric fundus, which proved to be caliber-persistent artery of the stomach on pathological examination. The tortuosity of the abnormal vessel in this condition has been attributed to artefactual contraction of the stomach following excision and formalin fixation. This is the first reported case in which a pathologically proven lesion has been clearly visualized by angiography. This demonstrates that the submucosal vessel is truly and not artifactually sinuous. It is proposed that angiographic demonstration of a nontapering, convoluted artery in the territory of the left gastric artery is highly suggestive of caliber-persistent artery of the stomach.

Spontaneous intrajugular migration of long-term central venous access catheters.

Two patients with long-term central venous access catheters introduced via the right subclavian vein demonstrated catheter migration into the right internal jugular vein several months after satisfactory catheter placement. One patient developed internal jugular vein thrombosis, which was treated with direct infusion of urokinase before catheter removal. In the other patient, the catheter was repositioned by using an intravascular snare loop, which was introduced via the femoral vein. In the first patient, an interim chest radiograph suggested the mechanism by which the catheter had migrated and provided a clue for early detection of catheter migration.

An artificial intelligence program for the radiologic diagnosis of brain lesions.

A software program has been developed that uses a frame-based expert system for differential diagnosis in neuroradiology. A frame-based expert system is used to store the magnetic resonance (MR) and computed tomographic (CT) imaging characteristics of over 100 known brain disorders in object-like entities. The frames are organized in a hierarchic structure in which lower order frames inherit attributes from higher order frames, with the highest frame containing information that applies to all the other frames. Program execution follows a consultation paradigm with a dynamic database. A decision tree menu provides a user-friendly interface with which to navigate through the network, based on features of the lesion as depicted on MR and CT images. The system can provide a differential diagnosis based on the MR imaging findings alone with information criteria including the signal intensity of the lesion on T1- and T2-weighted images, the location of the lesion, and the presence or absence of mass effect. The differential diagnosis may be further refined by adding CT-related information, including CT attenuation and the presence or absence of calcification and contrast enhancement.

Intra-arterial cisplatin treatment of unresectable or medically inoperable invasive carcinoma of the bladder.

Five patients between 72 and 82 years old received 5 to 6 treatments of 50 to 75 mg. per m.2 cisplatin by bilateral internal iliac artery infusion for unirradiated invasive transitional cell carcinoma of the bladder. Of the patients 3 also were diabetics and 1 had congestive heart failure. Treatment was tolerated extremely well, although most courses were associated with moderate to severe nausea and vomiting lasting several hours. Of 4 evaluable patients 3 achieved complete remission and 1 achieved a good partial remission. An additional 55-year-old woman with a large invasive bladder carcinoma fixed to surrounding structures was treated with 4 courses of 100 mg. per m.2 intra-arterial cisplatin. This patient had a marked decrease in tumor size, permitting surgical resection of all known residual tumor. A 49-year-old patient with large pelvic lymph node metastases from a squamous cell carcinoma of the bladder achieved only minimal decrease in tumor size after 3 courses of 100 mg. per m.2 intra-arterial cisplatin. We conclude that intra-arterial cisplatin can be highly effective for localized invasive bladder cancer even when relatively low doses are used. With proper care the regimen can be used safely and effectively in elderly patients with medical contraindications to an operation.

Pulsatile buttock mass: report of two cases and a review of the literature.

The presence of any pulsatile mass suggests an underlying aneurysm. When such masses occur in the buttock, the differential diagnosis includes aneurysms arising from branches of gluteal vessels or aneurysms developing in a persistent sciatic artery (PSA). The investigation and management of two patients with pulsatile masses are described. Review of the embryologic aspects of these masses and the important literature on the subject led to the conclusions that when a pulsatile buttock mass is encountered, an anomalous PSA should be suspected. A gluteal artery aneurysm can be treated by ligation or occlusion, but for a sciatic artery aneurysm surgical ablation is necessary and distal perfusion must be achieved postoperatively.

Peptic ulcer-induced gastroaortic fistula: difficulty in making the diagnosis with selective angiography.

We report a patient who had a gastroaortic fistula. This rare, potentially curable cause of torrential upper gastrointestinal hemorrhage is usually secondary to perforation of a gastric ulcer into the distal thoracic aorta. Hiatal hernia and previous gastroesophageal surgery (as in our patient) are important contributing factors in its genesis. It is essential to suspect this condition clinically so that the correct angiographic diagnosis can be made by biplane mid-stream thoracoabdominal aortography.

Hemobilia complicating elective laparoscopic cholecystectomy: a case report.

Iatrogenic injury to the hepatic or cystic arteries can occur during laparoscopic cholecystectomy and can be seen in isolation or in association with bile-duct injury. The most common manifestation of arterial injury is intraoperative hemorrhage; also, interruption of the right hepatic artery can occur without hemorrhage, and this can be clinically insignificant or associated with hepatic ischemia. A less common manifestation of arterial injury during laparoscopic cholecystectomy is presented. A 48-year-old woman had a pseudoaneurysm of the major anterior branch of the right hepatic artery in association with an injury to the common hepatic duct. This complication presented as massive hemobilia after she had been discharged from the hospital. Definitive repair of the pseudoaneurysm was carried out at the time of Roux-en-Y hepaticojejunostomy for correction of the associated duct injury. This unusual vascular complication should be considered in patients after laparoscopic cholecystectomy who demonstrate evidence of late occult or obvious hemorrhage.

Diagnostic value of arterial blood gas measurement in suspected pulmonary embolism.

Pulmonary embolism (PE) is a common and lethal yet treatable condition. Several authors have reported on the diagnostic value of combinations of arterial blood gas (ABG) and other clinical data (i. e., prediction rules), and have claimed that these combinations can be safely used to exclude PE. The purpose of this investigation was to evaluate the diagnostic value of ABG measurement and to attempt to validate the ABG prediction rules published by these various authors for the assessment of patients with suspected PE. Two hundred ninety-three consecutive patients referred for imaging to investigate suspected PE were approached to participate in the investigation. ABG and other clinical data were obtained from consenting and eligible patients before an outcome classification (PE versus non-PE) was performed. None of the ABG data or prediction rules had sufficient negative predictive value, specificity, or likelihood ratios to be useful in the management of patients with suspected PE. We conclude that ABG data alone or in combination with other clinical data are not useful in the assessment of suspected PE.

Günther Tulip Retrievable Vena Cava Filter: results from the Registry of the Canadian Interventional Radiology Association.

PURPOSE: To report data collected by the Canadian Registry of the Günther Tulip Retrievable Filter (GTF). MATERIALS AND METHODS: Between February 1998 and December 2000, 90 patients at eight hospitals underwent implantation of 91 GTFs. There were 45 male patients and 45 female patients, age 17-88 years, with a mean age of 49 years. Indications for filter placement were pulmonary embolism (PE) or deep vein thrombosis (DVT) with a contraindication to anticoagulation in 83 patients, prophylaxis after massive PE in one, prophylaxis for proximal free-floating thrombus in one, and prophylaxis with no DVT or PE in six patients (major trauma, n = 4; high preoperative risk, n = 2). GTF retrieval was attempted in selected patients from a right internal jugular vein approach. RESULTS: One GTF was inadvertently placed in the right iliac vein and could not be retrieved. There were no other major placement complications. GTF retrieval was attempted in 52 patients (53 GTFs); 52 GTFs were successfully retrieved from 51 patients. Implantation times were 2-25 days (mean, 9 d). Of these 51 patients, 37 underwent follow-up for 5-420 days (mean, 103 d) after filter retrieval. Four patients (8% of retrieved GTFs) required reinsertion of a permanent filter 17-167 days (mean, 78 d) after GTF retrieval as a result of bleeding from anticoagulation (n = 2) or because the patient required further surgery (n = 2). One other patient had recurrent DVT 230 days after retrieval; no PE or other complication was documented in the retrieval group. GTFs were not retrieved from 39 patients for various reasons. Of these 39 patients, 25 underwent follow-up 7-420 days (mean, 85 d) after filter placement. Two patients developed filter occlusion (5%); no other complications were documented. CONCLUSION: The GTF has a broad range of utility: it can be used as a permanent filter or retrieved after implantation periods of 15 days and possibly longer. However, indications for retrieval require further study, as does the maximum implantation time.