Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “EMBOLISM”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 649 records · Page 36Linked to original sources
PubMed2002

Capillary embolization using ethiodol-ethanol for complete renal ablation in Swine.

RATIONALE AND OBJECTIVES: To evaluate the effect of capillary embolization with superselectively administered 1:1 Ethiodol-ethanol mixture (EEM) for complete nephrectomy in normal porcine kidneys. MATERIALS AND METHODS: One kidney in each animal was completely embolized by sequential segmental arterial injections of the EEM via a microcatheter until complete capillary stasis occurred. Group 1 (n = 5): Initial embolization did not occlude the arterial compartment. Group 2 (n = 7): The capillary embolization was performed in conjunction with absolute ethanol injection and coil placement during balloon catheter occlusion. RESULTS: Group 1: Complete recanalization occurred following the EEM embolization (1-week). After the repeat embolization (EEM + pure ethanol without balloon occlusion), three of five kidneys showed partial recanalization (2-weeks). Following a third embolization (EEM + coil) in two pigs, one kidney showed partial recanalization (12-weeks). Group 2: Complete renal artery occlusion was achieved in all kidneys with no recanalization. Histologically, four kidneys exhibited total ablation whereas three showed minimal preexisting parenchyma (8-weeks). CONCLUSIONS: Permanent arterial occlusion with histologically complete renal ablation was achieved using a two-phase technique of homogeneous capillary embolization with 1:1 EEM and ethanol and coil occlusion performed during temporary balloon occlusion. Sequential segmental EEM injections alone did not produce permanent capillary embolization.

Animals↗
PubMed2003

Superselective microcoil embolization for the treatment of lower gastrointestinal hemorrhage.

PURPOSE: To evaluate the safety and effectiveness of superselective microcoil embolization for the treatment of lower gastrointestinal (LGI) hemorrhage. MATERIALS AND METHODS: A retrospective review of LGI superselective microcoil embolization data for a 10-year period was performed. During this period, twenty-two patients with evidence on angiography of LGI bleeding underwent superselective microcoil embolization. Hemorrhage was treated in the colon (n = 19) and jejunum (n = 3). Ivalon was used adjunctively in two patients and gelfoam was used as a secondary agent in two additional patients. Postembolization ischemia was evaluated objectively in 14 patients by colonoscopy (n = 10), surgical specimen (n = 3), and barium enema (n = 1). All patients were followed for clinical evidence of bowel ischemia. Four patients died before further follow-up could be performed. Additionally, 122 cases of LGI hemorrhage treated with superselective microcoil embolization were identified in a review of the literature. A meta-analysis was then performed, combining the data in this study and the data from the literature, to estimate the rate of major and minor ischemic complications on a total of 144 superselective microcoil embolizations. RESULTS: Immediate hemostasis was achieved in all 22 patients in this study. Complete clinical success was achieved in 86% of patients (19 of 22 patients). Rebleeding occurred in 14% of patients (3 of 22 patients) and each underwent colonoscopic intervention with success. Postembolization objective follow-up was performed in 64% of patients (14 of 22 patients). Ten patients underwent follow-up colonoscopy; one patient received a follow-up barium enema; and three patients underwent subsequent surgery. Colonic resection (one partial and one total) was performed in two patients. The partial colectomy was performed in a patient who had been diagnosed with colonic polyps and dysplasia. The total colectomy was performed on a patient with history of chronic LGI bleeding complicated by long-term anticoagulation therapy and a history of tubular adenoma resection. The third surgical patient (16 months old) underwent a follow-up exploratory laparotomy after embolization of a proximal jejunal branch of the superior mesenteric artery. None of the three patients who underwent surgery were found to have postembolic ischemic changes in the bowel specimen. Four patients in this study died, for reasons unrelated to hemorrhage or embolization, before further follow-up could be performed. The last four patients were followed clinically and experienced no symptoms of intestinal ischemia. A minor ischemic complication was reported in 4.5% of patients (1 of 22 patients), and there were no major ischemic complications (0%) in this series. A review of the data from 122 cases of LGI superselective microcoil embolization in the literature is also presented. Combined with the data in this study, the minor complication rate was 9% (13 of 144 patients), and the major complication rate was 0% (0 of 144 patients). CONCLUSION: Superselective microcoil embolization is a safe and effective treatment for LGI hemorrhage.

Adolescent↗
PubMed2005

Internal iliac artery coil embolization in the prevention of potential type 2 endoleak after endovascular repair of abdominal aortoiliac and iliac artery aneurysms: effect of total occlusion versus residual flow.

PURPOSE: To evaluate whether the presence of type 2 endoleak after internal iliac artery (IIA) coil embolization in patients with residual antegrade flow through the coils is more frequent than in patients who presented with total occlusion of the IIA after embolization. MATERIALS AND METHODS: Records were reviewed of 45 patients who underwent unilateral (n = 37) or bilateral (n = 8) IIA coil embolization between 1998 and 2004 for endovascular repair of aortoiliac aneurysms (n = 32), iliac artery aneurysms (n = 12), pseudoaneurysm (n = 1), or distal type 1 endoleak after placement of an aortoiliac stent-graft (n = 8). A total of 53 IIAs were embolized by means of coils and/or microcoils. Computed tomography (CT) was used for follow-up in 40 patients, angiography was used in three, and color Doppler ultrasonography was used in three. RESULTS: At the end of the embolization procedure, 23 IIAs were occluded and 30 IIAs demonstrated residual antegrade flow through the coils. Control CT demonstrated two type 2 endoleaks after endovascular stent-graft placement resulting from retrograde blood flow into the left IIA main branch via a patent iliolumbar artery. One of these two patients showed residual antegrade flow through the coils at the end of the IIA embolization procedure, and the other patient underwent complete coil embolization of the ostia of the anterior and posterior division but not of the main trunk of an aneurysmal IIA. CONCLUSION: IIA coil embolization with residual antegrade flow through the coils causes no greater incidence of type 2 endoleak after aortoiliac or iliac stent-graft placement. However, care must be taken in case of a proximal postostial origin of the iliolumbar artery on the IIA, which may cause type 2 endoleak if not embolized.

Aged↗
PubMed2006

A simple diagnostic strategy in hospitalized patients with clinically suspected pulmonary embolism.

OBJECTIVES: Diagnostic strategies in patients with suspected pulmonary embolism have been extensively studied in outpatients; their value in hospitalized patients has not been well established. Our aim was to determine the safety and clinical utility of a simple diagnostic strategy in hospitalized patients with suspected pulmonary embolism. DESIGN: Prospective management study. SETTING: Twelve teaching hospitals (five academic, seven general hospitals). SUBJECT: A total of 605 hospitalized patients with clinically suspected pulmonary embolism. All patients completed the study. INTERVENTIONS: First the clinical decision rule (CDR)-score was calculated. An unlikely CDR-score in combination with a normal D-dimer excluded pulmonary embolism. All other patients underwent helical computed tomography (CT). CT either diagnosed or excluded pulmonary embolism, in which case anticoagulants were started or withheld. All patients were instructed to report symptoms of venous thrombosis. Objective tests were performed to confirm venous thromboembolism. The primary outcome was the incidence of symptomatic venous thrombosis during 3-month follow-up. RESULTS: The combination of an unlikely CDR-score and a normal D-dimer excluded pulmonary embolism in 60 patients (10% of all patients); no venous thromboembolic event occurred during follow-up (0%; 95% CI 0-6.7%). CT excluded pulmonary embolism in 380 patients; during follow-up venous thromboembolism occurred in five patients (1.4%; 95% CI 0.4-3.1%). CONCLUSIONS: An unlikely CDR-score in combination with a normal D-dimer appears to exclude pulmonary embolism safely in hospitalized patients. Before clinical implementation it is important this safety is confirmed by others. CT testing was obviated in only 10% of patients. CT can safely exclude pulmonary embolism in hospitalized patients.

Algorithms↗
PubMed2006

The effects of experimental venous carbon dioxide embolization on hemodynamic and respiratory variables.

BACKGROUND: Laparoscopic liver resection is a relatively new surgical procedure. Carbon dioxide (CO2) pneumoperitoneum and laparoscopic liver dissection are recognized as risk factors for CO2 embolism to the pulmonary circulation. The embolization can be difficult to detect and can theoretically increase peri-operative morbidity. The aim of this study was to evaluate the cardiopulmonary effects in a pig model during a time period of 4 h after an experimental CO2 embolization. METHODS: Eleven piglets were anesthesized. Nine were embolized with a single intravenous injection of 0.4 ml/kg CO2 and two served as controls. Respiratory and cardiovascular variables, including pulmonary artery pressure and cardiac output, were monitored for 4 h after embolization, and arterial blood gases were monitored on-line. RESULTS: The embolized piglets had an increase in ventilatory dead space, pulmonary vascular resistance and pulmonary artery pressure and a decrease in cardiac output that lasted throughout the 4-h observation time. The mean arterial pressure and heart rate were unchanged. An early sign of embolization was a rapid fall in end-tidal CO2 and P(a)O2 and a rise in P(a)CO2. CONCLUSION: Negative changes in cardiopulmonary physiology persisted for at least 4 h after a single intravenous CO2 injection, in spite of this gas being highly soluble in blood. This is a more prolonged influence of CO2 embolization than previously described. Extensive monitoring for early detection of an embolization may be recommended to limit morbidity in patients undergoing laparoscopic liver surgery.

Animals↗
PubMed1997

Percutaneous microcoil embolization of intraperitoneal intrahepatic and extrahepatic biliary fistulas.

BACKGROUND: Persistent intraperitoneal biliary fistulas are associated with significant morbidity and mortality. Percutaneous drainage, stenting, and endoscopic sphincterotomy or embolization of biliary radicals have largely replaced the need for hepatic resection or biliary reconstruction in managing such fistulas. When endoscopy is contraindicated, a previously undescribed technique of percutaneous embolization of intrahepatic and extrahepatic biliary fistula following penetrating liver trauma, and orthotopic liver transplant and its application in three patients, will be discussed. METHODS: Embolization procedures were performed by an interventional radiologist. Percutaneous trans-hepatic cholangiography via a standard right-side approach or via tube cholangiography was initially performed and the fistula defined. Coaxial catheter systems were used (5 Fr angiography catheters and Tracker 18 infusion catheters), and were positioned within the biliary tree as close as possible to the origin of the fistula. Embolization was performed using vascular Embolization 28 coils (WA Cook) 2-3 mm x 2 cm coils, straight Hilal 18 embolization coils (WA Cook) 5-7 cm, as well as Gelfoam (Upjohn) 1 mm pellets, and Histoacryl (B. Braun) 0.25-1 mL. Occlusion of the duct was confirmed by a selective intrahepatic cholangiogram. In cases of multiple fistulas several embolizations were performed at subsequent procedures. Follow-up is over 13 months without adverse event. RESULTS: The technique was used in the three cases and was successful in all. A peripheral biliary fistula required embolization twice and two cystic leaks were cured after a single attempt. CONCLUSIONS: Percutaneous embolization of biliary fistulas provides a management option in cases where conservative treatment has failed and other techniques are relatively contraindicated. The technique is effective and safe in skilled hands, and avoids major surgery. The long-term effect of microcoils in the biliary tree is unknown.

Adult↗
PubMed2006

Transesophageal echocardiography impacts management and evaluation of patients with stroke, transient ischemic attack, or peripheral embolism.

The relative impact of transesophageal echocardiography (TEE) on the management of patients with specific embolic events, namely nonhemorrhagic cerebrovascular accident (CVA), transient ischemic attack (TIA), or peripheral embolism is controversial. The impact of TEE in 234 adult subjects with CVA (n = 141), TIA (n = 59), or peripheral embolism (n = 34) was determined. TEE was diagnostic of a potential embolic source in 61%, 51%, and 62% of patients with CVA, TIA, and peripheral embolism, respectively (P = NS). TEE results changed medication or surgical treatment in 32%, 22%, and 32% of patients with CVA, TIA, and peripheral embolism, respectively (P = NS). Anticoagulation was started on the basis of TEE findings in 11%, 12%, and 18% of patients with CVA, TIA, and peripheral embolism, respectively (P = NS). In 77% of all patients, TEE findings confirmed as appropriate the empiric decision made prior to TEE, to anticoagulate (60%; 12/20) or not to anticoagulate (79%; 168/214). These data demonstrate that TEE findings have a significant and similar impact on the clinical management of patients with various types of potential embolism. Future studies addressing the effectiveness of treatment, guided by TEE findings, in the prevention of recurrent embolic events are needed.

Adolescent↗
PubMed1970

Diagnosis of pulmonary embolism. A correlative study of the clinical, scan, and angiographic findings.

Seventy-one patients with suspected pulmonary embolism had both pulmonary scans and angiograms. Clinically it was impossible to predict the absence or presence of subsequent angiographic evidence of pulmonary embolism in the individual patient. In 24 patients the scans showed defects that were believed to indicate a high probability of pulmonary embolism-namely, perfusion defects that corresponded to specific anatomical segments of the lung together with normal chest radiographs or radiographs suggestive of pulmonary embolism. Specific angiographic evidence of pulmonary embolism was found in 18 (75%) of these patients. Diffuse, patchy, and non-segmental perfusion defects were seen in 28 patients. Only seven (25%) of this group had angiographic abnormalities specific for embolism. In 12 patients with normal lung scans none showed subsequent evidence of embolism by angiography. It is concluded firstly that lung scanning is a sensitive screening procedure for pulmonary embolism and, secondly, that segmental perfusion defects are highly suggestive of pulmonary embolism.

Angiography↗
PubMed2005

Systematic review and meta-analysis of strategies for the diagnosis of suspected pulmonary embolism.

OBJECTIVES: To assess the likelihood ratios of diagnostic strategies for pulmonary embolism and to determine their clinical application according to pretest probability. DATA SOURCES: Medline, Embase, and Pascal Biomed and manual search for articles published from January 1990 to September 2003. STUDY SELECTION: Studies that evaluated diagnostic tests for confirmation or exclusion of pulmonary embolism. DATA EXTRACTED: Positive likelihood ratios for strategies that confirmed a diagnosis of pulmonary embolism and negative likelihood ratios for diagnostic strategies that excluded a diagnosis of pulmonary embolism. DATA SYNTHESIS: 48 of 1012 articles were included. Positive likelihood ratios for diagnostic tests were: high probability ventilation perfusion lung scan 18.3 (95% confidence interval 10.3 to 32.5), spiral computed tomography 24.1 (12.4 to 46.7), and ultrasonography of leg veins 16.2 (5.6 to 46.7). In patients with a moderate or high pretest probability, these findings are associated with a greater than 85% post-test probability of pulmonary embolism. Negative likelihood ratios were: normal or near normal appearance on lung scan 0.05 (0.03 to 0.10), a negative result on spiral computed tomography along with a negative result on ultrasonography 0.04 (0.03 to 0.06), and a d-dimer concentration < 500 mug/l measured by quantitative enzyme linked immunosorbent assay 0.08 (0.04 to 0.18). In patients with a low or moderate pretest probability, these findings were associated with a post-test probability of pulmonary embolism below 5%. Spiral computed tomography alone, a low probability ventilation perfusion lung scan, magnetic resonance angiography, a quantitative latex d-dimer test, and haemagglutination d-dimers had higher negative likelihood ratios and can therefore only exclude pulmonary embolism in patients with a low pretest probability. CONCLUSIONS: The accuracy of tests for suspected pulmonary embolism varies greatly, but it is possible to estimate the range of pretest probabilities over which each test or strategy can confirm or rule out pulmonary embolism.

Echocardiography↗
PubMed2001

Diagnostic value of transoesophageal echocardiography in suspected haemodynamically significant pulmonary embolism.

OBJECTIVE: To assess the value of transoesophageal echocardiography (TOE) for diagnosing suspected haemodynamically significant pulmonary embolism and signs of right ventricular overload at standard echocardiography. METHODS: 113 consecutive patients (58 male; 55 female), mean (SD) age 53.6 (13.3) years, in whom there was clinical suspicion of pulmonary embolism and right ventricular overload on transthoracic echocardiography, underwent TOE in addition to routine diagnostic procedures to identify pulmonary artery thrombi. RESULTS: TOE revealed thrombi in 32 of 51 patients who had suspected acute pulmonary embolism and in 31 of 62 with suspected chronic pulmonary embolism. In one patient a pulmonary angiosarcoma rather than chronic pulmonary embolism was found at surgery. The diagnosis of pulmonary embolism was confirmed in 77 patients by scintigraphy, spiral computed tomography, angiography, or necropsy (reference methods). While TOE failed to provide a diagnosis of pulmonary embolism in 15 of these 77 patients, no false positive findings were reported (sensitivity 80.5%, specificity 97.2%). In 11 and 26 cases, respectively, the thrombi were confined to the left or right pulmonary artery. Bilateral thrombi were found in 25 patients. Mobile thrombi were observed only in acute pulmonary embolism (in 19 of 32 patients). No complications of TOE were noted. CONCLUSIONS: TOE permits visualisation of pulmonary arterial thrombi, confirming the diagnosis in the majority of patients with pulmonary embolism and right ventricular overload. This may be useful for prompt decision making in patients with haemodynamic compromise considered for thrombolysis or embolectomy.

Echocardiography↗
PubMed1991

Role of transoesophageal echocardiography in evaluation of cardiogenic embolism.

OBJECTIVE: To determine the value of transoesophageal echocardiography in the assessment of selected patients at risk of cardiogenic embolism or after it. DESIGN: Prospective comparison of the results of transoesophageal and transthoracic echocardiography. Transoesophageal echocardiography was performed with a 5 MHz single plane phased array transducer. SETTING: University teaching hospital. PATIENTS: 100 patients referred for transoesophageal echocardiography after a cerebral ischaemic event or peripheral arterial embolism (n = 63), before percutaneous balloon dilatation of the mitral valve (n = 23), or before electrical cardioversion of atrial fibrillation (n = 14). RESULTS: Transthoracic echocardiography showed potential sources of embolism in four patients including left ventricular thrombus in two patients (with one false positive), left atrial appendage thrombus (n = 1), and patent foramen ovale (n = 1). Transoesophageal echocardiography showed 59 potential embolic sources in 45 patients including left atrial spontaneous echo contrast (n = 33), left atrial appendage thrombus (n = 13), left ventricular thrombus (n = 5), patent foramen ovale (n = 3), left ventricular spontaneous echo contrast (n = 2), mitral valve prosthesis thrombus (n = 1), mitral valve prolapse (n = 1), and pronounced aortic atheroma (n = 1). Transoesophagal echocardiography showed potential embolic sources in 36/53 (68%) patients with atrial fibrillation compared with 9/47 (19%) patients in sinus rhythm. Percutaneous balloon dilatation of the mitral valve was performed without embolic complications in 18 patients without left atrial thrombi and in three patients with small fixed thrombi in the left atrial appendage. It was cancelled in two patients with large thrombi in the left atrial appendage. Cardioversion was performed without embolic complications in 14 patients without left atrial thrombi. CONCLUSIONS: Transoesophageal echocardiography detects potential sources of embolism better than transthoracic echocardiography in selected patients at risk of cardiogenic embolism or after it.

Adult↗
PubMed1993

Distinguishing between acute and subacute massive pulmonary embolism by conventional and Doppler echocardiography.

OBJECTIVE: To determine the ability of conventional and Doppler echocardiography to distinguish between minor, acute massive, and subacute massive pulmonary embolism in patients with confirmed pulmonary embolism. DESIGN: Prospective study of a consecutive series of 47 patients with confirmed pulmonary embolism. SETTING: Department of internal medicine, university clinic. PATIENTS: 11 patients (23%) had minor, 23 patients (49%) had acute massive, and 13 patients (28%) had subacute massive pulmonary embolism. RESULTS: Dilatation of the right ventricular cavity (33 (92%)) and asynergy of the right ventricular free wall (29 (81%)) were seen only in patients with acute and subacute massive pulmonary embolism (n = 36). 23 (64%) with pulmonary hypertension had tricuspid regurgitation. The velocity of the tricuspid regurgitant jet correlated with the pulmonary arterial pressure (r = 0.88, SEE = 11.6 mm Hg) and was significantly lower in patients with acute massive pulmonary embolism (3.0 (0.4) m/s, n = 12) than in patients with subacute massive pulmonary embolism (4.2 (0.6) m/s; n = 11) (p < 0.001). The use of predefined indices (right ventricular free wall thickness > 5 mm; tricuspid regurgitant jet velocity > 3.7 m/s; and the occurrence of both a dilated right ventricular cavity with normal interventricular septal motion, or an inspiratory collapse of the inferior vena cava, or both) correctly identified 11 of 13 patients (85%) with subacute massive pulmonary embolism. CONCLUSION: Conventional and Doppler echocardiography were successful in evaluating the haemodynamic consequences of pulmonary embolism.

Acute Disease↗
PubMed1998

Initially unresectable hilar cholangiocarcinoma: hepatic regeneration after transarterial embolization.

PURPOSE: To assess with volumetric computed tomography (CT) the pattern and extent of hepatic regeneration induced with transarterial embolization of initially unresectable hilar cholangiocarcinoma (Klatskin tumor). MATERIALS AND METHODS: In this prospective study, 13 patients (four men, nine women) with hilar cholangiocarcinoma, aged 43-74 years (mean +/- 1 standard deviation, 59.9 years +/- 9.6), underwent preoperative embolization of the right hepatic lobe. Embolization was performed transarterially by using four to 15 embolization coils. Volumetric measurements of the entire liver, left hepatic lobe, and spleen were performed with contrast material-enhanced and unenhanced helical CT before and after embolization in all patients. RESULTS: After right lobe embolization, volumetric helical CT measurements revealed a 2%-33% decrease (mean, 10%) in the volume of the affected right hepatic lobe, an 11%-68% increase (mean, 37%) in the volume of left hepatic lobe parenchyma, and variations in splenic volume of -5% to +28% (mean, +11%). Nine patients underwent extended hepatectomy 27-75 days (mean, 44 days) after embolization. No patient had severe complications due to embolization. CONCLUSION: In patients with an initially unresectable bilateral Klatskin tumor, right lobar arterial coil embolization results in enlargement of the left hepatic lobe (as verified with volumetric helical CT), thus allowing right hemihepatectomy.

Adult↗
PubMed1996

Hypoxic pulmonary vasoconstriction and gas exchange in acute canine pulmonary embolism.

Hypoxic pulmonary vasoconstriction (HPV) is inhibited in several models of acute lung injury. Whether HPV is preserved in pulmonary embolism is unknown. We investigated the effects of a reduction in the fraction of inspired O2 (FIO2) on pulmonary hemodynamics and gas exchange in anesthetized dogs before and after autologous blood clot pulmonary embolism. In a first group of 14 dogs, stimulus-response curves for HPV were constructed as pulmonary arterial pressure (Ppa) vs. FIO2 varied between 1.0 and 0.06 at a cardiac output (Q) kept constant at 3.5 l.min-1.m-2. Gas exchange was evaluated by using the multiple inert-gas elimination technique at FIO2 of 1.0, 0.4, and 0.1. Embolism decreased the relative magnitude of HPV, expressed as the gradient between Ppa and pulmonary arterial occluded pressure in hypoxia divided by (Ppa-pulmonary arterial occluded pressure) at FIO2 of 1.0, from 1.8 to 1.2 (P < 0.05). Retention minus excretion gradients for sulfur hexafluoride and ethane were increased by decreased FIO2 (P < 0.005 and P < 0.05, respectively) before but not after embolism. Hypoxia-induced deterioration in gas exchange before embolism was related to the amount of baseline very low ventilation-perfusion (VA/Q) ratios. Similar results were obtained in a second group of seven dogs with Q decreased to maintain Ppa at the same average value as before embolism. However, gas exchange was not affected by inspiratory hypoxia before as well as after embolism in this group, which presented with a lesser amount of baseline very low VA/Q. In both groups of dogs, increase in the FIO2 from 0.4 to 1.0 did not affect gas exchange. We conclude that 1) pulmonary embolism is associated with a partial inhibition of HPV, 2) HPV does not contribute to preserve gas exchange in pulmonary embolism, and 3) a strong HPV may deteriorate gas exchange in severe hypoxia in the presence of minor very low VA/Q inequality.

Animals↗
PubMedDate not supplied

Clinical validity of negative helical computed tomography for clinical suspicion of pulmonary embolism.

BACKGROUND: Helical computed tomography has been introduced for the diagnosis of pulmonary embolism. OBJECTIVE: To determine the clinical safety of withholding anticoagulant treatment in patients with suspicion of pulmonary embolism and negative helical computed tomography study. METHODS: During a 9-month period, we performed a prospective study including 209 consecutive patients who underwent helical computed tomography for clinical suspicion of pulmonary embolism. In 53 patients (25.5%), helical computed tomography was diagnostic for pulmonary embolism, and in 24 patients (11.5%) it was indeterminate. In 132 patients (63%), the examination was negative for pulmonary embolism and no anticoagulation treatment was given. A clinical 3-month follow-up was carried out. During this period, 29 patients (22%) were excluded because anticoagulation therapy was initiated for other reasons, or because other diagnostic techniques were performed for pulmonary embolism. Four patients were lost in the 3-month period. In the end, 99 patients (75%) were included in the clinical follow-up. RESULTS: Out of the 99 patients, 9 (9%) died during the 9-month follow-up, the cause of death in each case was not due to thromboembolic venous disease. No venous thromboembolic events were detected in the other 90 patients. Negative predictive value of helical computed tomography for pulmonary embolism was 99.09% (95% CI, 95.03-99.97%). CONCLUSIONS: In patients with clinical suspicion of pulmonary embolism and initial negative helical computed tomography from whom anticoagulants are withheld, no thromboembolic disease was detected in a 3-month follow-up. We consider helical computed tomography an effective method for ruling out pulmonary embolism as well as a front-line tool for diagnosis.

Age Distribution↗
PubMed2005

Diagnostic strategy using a modified clinical decision rule and D-dimer test to rule out pulmonary embolism in elderly in- and outpatients.

Excluding or confirming pulmonary embolism remains a diagnostic challenge. In elderly patients pulmonary embolism is associated with substantial co-morbidity and mortality, and many elderly patients with suspected pulmonary embolism are inpatients. The safety and efficacy of the combination of a clinical probability (CDR) and d-dimer test in excluding pulmonary embolism in this group is unclear. We retrospectively analysed data of two prospective studies of consecutive in-and outpatients with suspected pulmonary embolism. The patients were categorized into three age groups: <65 years, 65-75 years and >75 years. The sensitivity, negative predictive value and the proportion of patients with the combination of a non-high CDR score according to Wells (< or = 4) and a normal d-dimer result were calculated for each group. In 747 consecutive patients with suspected pulmonary embolism, sensitivity and negative predictive value of a non-high CDR and a normal d-dimer result in outpatients (n=538) of all age categories (<65 years, 65-75 years and >75 years) were both 100%. These tests were, however, less reliable for inpatients(n=209), irrespective of their age (sensitivity 91% [ CI: 79-98%], negative predictive value 88 % [CI: 74-96%]. The proportion of both in-and outpatients >75 years with a non-high CDR and a normal d-dimer concentration was only 14%, whereas this was 22% in patients 65-75 years and 41% among in-and outpatients <65 years, respectively. In elderly outpatients the combination of a non-high CDR and a normal d-dimer result is a safe strategy to rule out pulmonary embolism. However, in inpatients this algorithm is not reliable to safely exclude pulmonary embolism. In addition, the proportion of patients >65 years in which this strategy excludes pulmonary embolism is markedly lower compared to younger patients.

Adolescent↗
PubMed2002

Microplasmin: a novel thrombolytic that improves behavioral outcome after embolic strokes in rabbits.

BACKGROUND AND PURPOSE: It has been proposed that the novel thrombolytic microplasmin may be useful in the treatment of ischemic stroke. In the present study the effects and safety profile of microplasmin were evaluated in 2 rabbit embolic stroke models that have been used successfully to develop tissue plasminogen activator (tPA) as the only Food and Drug Administration-approved treatment for stroke. The rabbit small clot embolic stroke model (RSCEM) and rabbit large clot embolic stroke model (RLCEM) were used to determine the potential neuroprotective properties and safety profile of microplasmin, respectively, after an embolic stroke. METHODS: Rabbits were embolized by injecting small blood clots (RSCEM) or large blood clots (RLCEM) into the cerebral circulation. For the RSCEM, 126 rabbits were included, with behavioral analysis conducted 24 hours later, allowing for determination of the effective stroke dose (ES50) or clot amount (milligrams) that produces severe neurological deficits in 50% of rabbits. For RLCEM safety study analysis, 47 rabbits were included, with postmortem analyses consisting of assessment of hemorrhage and infarct rate and size. In test animals microplasmin was infused intravenously 60 minutes after embolization, whereas control rabbits were given infusions of the saline/Plasma-Lyte vehicle with all assessments performed in a blinded fashion. RESULTS: In the RSCEM, a drug is considered neuroprotective if it significantly increases the ES50 compared with the vehicle-treated control group. The ES50 of the vehicle-treated control group 24 hours after embolization was 1.36+/-0.42 mg (n=38). Microplasmin, infused starting 60 minutes after embolization, increased the ES50 to 2.32+/-0.57 (n=21), 1.89+/-0.48 (n=21), 2.81+/-0.55 (n=22), and 1.89+/-0.28 mg (n=24) for the 1-, 2-, 4-, and 8-mg/kg doses, respectively. There was a statistically significant behavioral improvement in the 4-mg/kg dose arm (P=0.040). The microplasmin dose of microplasmin that was statistically significant (4 mg/kg) was subsequently determined to be safe in the RLCEM because it did not increase the incidence of hemorrhages (56%) compared with vehicle-treated rabbits (63%), nor did it significantly alter hemorrhage volume, infarct rate, or infarct volume. CONCLUSIONS: The present study shows that microplasmin improves behavioral rating scores in the RSCEM when administered 60 minutes after embolization, at a dose that does not increase hemorrhages in the RLCEM. This is in contrast to tPA, which significantly enhances the hemorrhage rate in the RLCEM.

Animals↗
PubMed1994

Carotid angioplasty. Detection of embolic signals during and after the procedure.

BACKGROUND AND PURPOSE: Carotid angioplasty may offer an effective treatment for carotid stenosis, but there has been concern about the incidence and clinical consequences of distal embolization. Transcranial Doppler monitoring in carotid endarterectomy has demonstrated embolic signals during this procedure. We used this technique in patients undergoing carotid angioplasty. METHODS: Transcranial Doppler ultrasound was used to monitor for embolic signals in the ipsilateral middle cerebral artery before and during 10 technically successful carotid angioplasties and at various standardized times in the following month. RESULTS: In the month before angioplasty asymptomatic embolic signals were detected in 3 of 10 patients. During angioplasty multiple embolic signals were detected immediately after balloon inflation in 9 of 10 subjects. A minor ipsilateral cerebral ischemic event occurred in 1 of these 9, but the other 8 were asymptomatic. Embolic signals were common immediately after the procedure and intra-arterial femoral catheter removal (8 of 10 subjects) but thereafter became less frequent and were present in 1 of 5 at 4 hours, 2 of 10 at 48 hours, 1 of 6 at 7 days, and 1 of 10 at 1 month. CONCLUSIONS: Embolization at the time of carotid angioplasty is very common but usually asymptomatic; monitoring by means of Doppler ultrasound will allow the effectiveness of measures to reduce this embolization to be studied. Late embolization occurs in a minority of patients and may account for the small but significant risk of delayed stroke. Doppler monitoring may allow identification of patients at risk and assessment of the effectiveness of prophylactic therapy.

Aged↗