Covered transjugular intrahepatic portosystemic shunt versus endoscopic therapy + ß-blocker for prevention of variceal rebleeding.

UNLABELLED: Gastroesophageal variceal bleeding in patients with cirrhosis is associated with significant morbidity and mortality, as well as a high rebleeding risk. Limited data are available on the role of transjugular intrahepatic portosystemic shunt (TIPS) with covered stents in patients receiving standard endoscopic, vasoactive, and antibiotic treatment. In this multicenter randomized trial, long-term endoscopic variceal ligation (EVL) or glue injection + ß-blocker treatment was compared with TIPS placement in 72 patients with a first or second episode of gastric and/or esophageal variceal bleeding, after hemodynamic stabilization upon endoscopic, vasoactive, and antibiotic treatment. Randomization was stratified according to Child-Pugh score. Kaplan-Meier (event-free) survival estimates were used for the endpoints rebleeding, death, treatment failure, and hepatic encephalopathy. During a median follow-up of 23 months, 10 (29%) of 35 patients in the endoscopy + ß-blocker group, as compared to 0 of 37 (0%) patients in the TIPS group, developed variceal rebleeding (P = 0.001). Mortality (TIPS 32% vs. endoscopy 26%; P = 0.418) and treatment failure (TIPS 38% vs. endoscopy 34%; P = 0.685) did not differ between groups. Early hepatic encephalopathy (within 1 year) was significantly more frequent in the TIPS group (35% vs. 14%; P = 0.035), but during long-term follow-up this difference diminished (38% vs. 23%; P = 0.121). CONCLUSIONS: In unselected patients with cirrhosis, who underwent successful endoscopic hemostasis for variceal bleeding, covered TIPS was superior to EVL + ß-blocker for reduction of variceal rebleeding, but did not improve survival. TIPS was associated with higher rates of early hepatic encephalopathy.

Radiological imaging and gastrointestinal tonometry add value in diagnosis of chronic gastrointestinal ischemia.

BACKGROUND & AIMS: The diagnosis of chronic gastrointestinal ischemia (CGI) remains a clinical challenge. We aimed to assess the diagnostic value of clinical features, visualization of the gastrointestinal arteries, and evaluation of mucosal perfusion in patients clinically suspected of CGI. METHODS: A total of 186 patients referred for suspicion of CGI were prospectively included and followed up. All patients had an extensive diagnostic work-up, including visualization of the gastrointestinal arteries with computed tomography, magnetic resonance, or conventional angiography, and mucosal perfusion with tonometry. The reference standard for CGI was persistent clinical response after adequate therapy. The diagnostic value of individual and combined tests was assessed with multivariable logistic regression analysis. RESULTS: A total of 116 (62%) patients were diagnosed with CGI. In a multivariable model solely based on clinical features, the strongest predictors for CGI were the presence of postprandial pain, weight loss per month in kilograms, concomitant cardiovascular disease, and presence of an abdominal bruit. However, this model showed limited discriminative ability for the presence or absence of CGI (c-statistic, 0.62). Adding radiologic imaging to the prediction model improved the discriminative ability substantially (c-statistic, 0.81). Adding tonometry to the prediction model further improved the discriminative ability of the model (c-statistic, 0.90). The combination of clinical features and tonometry with a c-statistic of 0.88 approximated the discriminative ability of the latter model. CONCLUSIONS: Clinical features alone have a limited value to assess CGI correctly. Visualization of the gastrointestinal arteries and evaluation of mucosal perfusion substantially improve the diagnosis of CGI. The strongest diagnostic contribution comes from mucosal perfusion assessment.

Endoscopic visible light spectroscopy: a new, minimally invasive technique to diagnose chronic GI ischemia.

BACKGROUND: The diagnosis of chronic GI ischemia (CGI) remains a clinical challenge. Currently, there is no single simple test with high sensitivity available. Visible light spectroscopy (VLS) is a new technique that noninvasively measures mucosal oxygen saturation during endoscopy. OBJECTIVE: To determine the diagnostic accuracy of VLS for the detection of ischemia in a large cohort of patients. DESIGN: Prospective study, with adherence to the Standards for Reporting of Diagnostic Accuracy. SETTING: Tertiary referral center. PATIENTS: Consecutive patients referred for evaluation of possible CGI. INTERVENTIONS: Patients underwent VLS along with the standard workup consisting of evaluation of symptoms, GI tonometry, and abdominal CT or magnetic resonance angiography. MAIN OUTCOME MEASUREMENTS: VLS measurements and the diagnosis of CGI as established with the standard workup. RESULTS: In 16 months, 121 patients were included: 80 in a training data set and 41 patients in a validation data set. CGI was diagnosed in 89 patients (74%). VLS cutoff values were determined based on the diagnosis of CGI and applied in the validation data set, and the results were compared with the criterion standard, resulting in a sensitivity and specificity of VLS of 90% and 60%, respectively. Repeated VLS measurements showed improvement in 80% of CGI patients after successful treatment. LIMITATIONS: Single-center study; only 43% of patients had repeated VLS measurements after treatment. CONCLUSIONS: VLS during upper endoscopy is a promising easy-to-perform and minimally invasive technique to detect mucosal hypoxemia in patients clinically suspected of having CGI, showing excellent correlation with the established ischemia workup.

Radial force measurements in carotid stents: influence of stent design and length of the lesion.

PURPOSE: To assess the differences in radial force of carotid stents and whether the length of the lesion influences the measurements. MATERIALS AND METHODS: Different models of tapered stents of similar size (length, 30 mm) were used. The tapered nitinol Acculink, Protégé, and Cristallo Ideale carotid artery stents and the straight, braided Elgiloy carotid Wallstent were compared. A measurement device consisting of three film loops along the stent body connected to aluminium rods with copper strain gauges was developed. Five stents of each type were deployed within 3-mm stenoses in simulated long (26 mm) and short (8 mm) stenoses. RESULTS: In the short stenosis simulation, the greatest radial force was seen in the Protégé stent, at 3.14 N ± 0.45, followed by the Cristallo Ideale stent (1.73 N ± 0.51), Acculink (1.16 N ± 0.21), and Wallstent (0.84 N ± 0.10; P < .001). In the long stenosis simulation, peak radial force again was highest in the Protégé stent (1.67 N ± 0.37), but the Acculink stent was second (0.95 N ± 0.12) and the Wallstent third (0.80 N ± 0.06). The Cristallo Ideale stent, in contrast to the short stenosis simulation, produced the least radial force (0.44 N ± 0.13) in the long stenosis simulation (P = .001). CONCLUSIONS: Radial forces exerted by carotid stents vary significantly among stent designs. Differences between stent types are dependent on the length of the stenosis. An understanding of radial force is necessary for a well-considered choice of stent type in each individual patient.

Stent placement in patients with atherosclerotic renal artery stenosis and impaired renal function: a randomized trial.

BACKGROUND: Little is known about the efficacy and safety of renal artery stenting in patients with atherosclerotic renal artery stenosis (ARAS) and impaired renal function. OBJECTIVE: To determine the efficacy and safety of stent placement in patients with ARAS and impaired renal function. DESIGN: Randomized clinical trial. Randomization was centralized and computer generated, and allocation was assigned by e-mail. Patients, providers, and persons who assessed outcomes were not blinded to treatment assignment. SETTING: 10 European medical centers. PARTICIPANTS: 140 patients with creatinine clearance less than 80 mL/min per 1.73 m(2) and ARAS of 50% or greater. INTERVENTION: Stent placement and medical treatment (64 patients) or medical treatment only (76 patients). Medical treatment consisted of antihypertensive treatment, a statin, and aspirin. MEASUREMENTS: The primary end point was a 20% or greater decrease in creatinine clearance. Secondary end points included safety and cardiovascular morbidity and mortality. RESULTS: Forty-six of 64 patients assigned to stent placement had the procedure. Ten of the 64 patients (16%) in the stent placement group and 16 patients (22%) in the medication group reached the primary end point (hazard ratio, 0.73 [95% CI, 0.33 to 1.61]). Serious complications occurred in the stent group, including 2 procedure-related deaths (3%), 1 late death secondary to an infected hematoma, and 1 patient who required dialysis secondary to cholesterol embolism. The groups did not differ for other secondary end points. LIMITATION: Many patients were falsely identified as having renal artery stenosis greater than 50% by noninvasive imaging and did not ultimately require stenting. CONCLUSION: Stent placement with medical treatment had no clear effect on progression of impaired renal function but led to a small number of significant procedure-related complications. The study findings favor a conservative approach to patients with ARAS, focused on cardiovascular risk factor management and avoiding stenting.

Intermittent claudication: clinical effectiveness of endovascular revascularization versus supervised hospital-based exercise training--randomized controlled trial.

PURPOSE: To compare clinical success, functional capacity, and quality of life during 12 months after revascularization or supervised exercise training in patients with intermittent claudication. MATERIALS AND METHODS: This study had institutional review board approval, and all patients gave written informed consent. Between September 2002 and September 2005, 151 consecutive patients who presented with symptoms of intermittent claudication were randomly assigned to undergo either endovascular revascularization (angioplasty-first approach) (n = 76) or hospital-based supervised exercise (n = 75). The outcome measures were clinical success, functional capacity, and quality of life after 6 and 12 months. Clinical success was defined as improvement in at least one category in the Rutherford scale above the pretreatment level. Significance of differences between the groups was assessed with the unpaired t test, chi(2) test, or Mann-Whitney U test. To adjust outcomes for imbalances of baseline values, multivariable regression analysis was performed. RESULTS: Immediately after the start of treatment, patients who underwent revascularization improved more than patients who performed exercise in terms of clinical success (adjusted odds ratio [OR], 39; 99% confidence interval [CI]: 11, 131; P < .001), but this advantage was lost after 6 (adjusted OR, 0.9; 99% CI: 0.3, 2.3; P = .70) and 12 (adjusted OR, 1.1; 99% CI: 0.5, 2.8; P = .73) months. After revascularization, fewer patients showed signs of ipsilateral symptoms at 6 months compared with patients in the exercise group (adjusted OR, 0.4; 99% CI: 0.2, 0.9; P < .001), but no significant differences were demonstrated at 12 months. After both treatments, functional capacity and quality of life scores increased after 6 and 12 months, but no significant differences between the groups were demonstrated. CONCLUSION: After 6 and 12 months, patients with intermittent claudication benefited equally from either endovascular revascularization or supervised exercise. Improvement was, however, more immediate after revascularization.

Long-term patient satisfaction after percutaneous treatment of peripheral vascular malformations.

PURPOSE: To determine long-term patient satisfaction for percutaneous treatment by using sclerosing agents (sclerotherapy) and/or arterial embolization for peripherally located vascular malformations (VMs). This treatment has been described as successful; however, there is a relative paucity of published long-term results. MATERIALS AND METHODS: This retrospective study was institutional review board approved; 107 patients treated for symptomatic VM were evaluated. After informed consent was obtained, 66 patients were sent a questionnaire regarding treatment effectiveness and patient satisfaction. Patient files and imaging data were retrieved to obtain information regarding the VMs and VM treatment. Kaplan-Meier survival curves were constructed to analyze clinical success rates over time. RESULTS: The most frequent reasons for patients to seek treatment were pain (89%, n = 59) and swelling (91%, n = 60). The majority of VMs were the low-flow venous type (83%, n = 55). Three months after treatment, clinical success was reported for 58% (n = 38) of patients and clinical failure was reported for 42% (n = 28). At 1-, 2-, 3-, 4-, and 5-year follow-up, clinical success was 49%, 49%, 42%, 42%, and 42%, respectively. Twenty-seven (40%) patients experienced complications, 12 of which required additional treatment. In all, 35 (53%) patients reported being satisfied with their treatment. Patient satisfaction was closely correlated with clinically successful long-term outcome of treatment. CONCLUSION: Initial partial or complete relief of VM complaints after percutaneous treatment is expected in 58% of patients, irrespective of VM size or classification. These results were durable over a 5-year follow-up period.

Transjugular intrahepatic portosystemic shunt in patients with chronic portal vein occlusion and cavernous transformation.

GOALS: To determine the feasibility of transjugular intrahepatic portosystemic shunt (TIPS) creation as a possible salvage intervention in patients with variceal bleeding and chronic portal vein thrombosis with cavernous transformation, refractory to endoscopic therapy. BACKGROUND: TIPS is technically feasible in partial portal vein occlusion or complete occlusion due to fresh thrombosis. However, when the portal vein occlusion is complete and chronic, placement of TIPS is technically difficult. STUDY: In a tertiary referral center setting 4 patients with portal hypertension associated complications, received TIPS, as salvage therapy. In all patients a covered stent was placed to the cavernous transformation. RESULTS: Creation of TIPS to the dilated veins of a cavernous transformation was feasible in patients for whom recanalization of the portal vein was not possible. However, the collaterals need to be suitably wide for placement of TIPS and the high-pressure collaterals should communicate with the varices. CONCLUSIONS: TIPS should be considered as salvage therapy when endoscopic treatment is unsuccessful in patients with chronic portal vein thrombosis and cavernous transformation.

Cardiac status after childhood growth hormone treatment of Turner syndrome.

CONTEXT: In Turner syndrome (TS), GH treatment is well established. Data on cardiac status after discontinuation of treatment are scarce. This study aimed to assess biventricular size and function in TS at least 6 months after discontinuation of GH treatment. METHODS: TS patients and healthy women prospectively underwent cardiac magnetic resonance imaging. Ventricular two-dimensional tomographic cine data were acquired to obtain biventricular volume, mass, and ejection fraction. Atrioventricular valve flow measurements were performed using a two-dimensional flow-sensitized sequence. Flow velocity curves were calculated and indices of biventricular diastolic filling were derived. RESULTS: Thirty-one patients [mean (sd) age 20 (2) yr, body surface area 1.75 (0.15) m(2), 5 (2) yr after GH discontinuation] and 23 normal control women [age 21 (2) yr, body surface area 1.80 (0.13) m(2)] were included. Compared with controls, patients had smaller mean end-diastolic volumes [right ventricle (RV), 84 (11) ml/m(2) vs. 79 (10), P = 0.02; left ventricle (LV), 81 (10) vs. 72 (9), P < 0.001], end-systolic volumes [RV 38 (7) ml/m(2) vs. 36 (6), P = 0.04; LV 34 (5) vs. 29 (4), P < 0.001], and stroke volumes [RV 46 (6) ml/m(2) vs. 43 (6), P = 0.03; LV, 47 (7) vs. 44 (4), P = 0.02]. Patients had a higher mean heart rate [79 (13) beats/min vs. 71 (10), P < 0.05]. Biventricular ejection fraction, mass, cardiac output, and diastolic filling pattern were comparable. CONCLUSION: After discontinuation of GH treatment TS patients showed no myocardial hypertrophy and well-preserved biventricular function. Ventricular volumes were smaller in Turner patients, compared with controls, whereas mean heart rate was higher. These last observations may be part of the natural development in TS and not linked to GH treatment, which at this point we consider safe.

Risks and benefits of transcatheter thrombolytic therapy in patients with splanchnic venous thrombosis.

Transcatheter local thrombolytic therapy in patients with acute, extended splanchnic venous thrombosis is controversial. Here we present our single-center experience with transcatheter thrombolytic therapy in these patients. All consecutive patients (n = 12) with acute, extended splanchnic venous thrombosis who underwent transcatheter thrombolytic therapy in our hospital, were included in this study. Thrombolytic therapy was successful for three thrombotic events and partially successful for four thrombotic events. Two patients developed minor procedure-related bleeding (17%). Six patients (50%) developed major procedure-related bleeding, with a fatal outcome in two. Transcatheter thrombolytic therapy in patients with acute, extended splanchnic vein thrombosis is found to be associated with a high rate of procedure-related bleeding. Therefore, thrombolysis should be reserved for patients in whom the venous flow cannot be restored by using conventional anticoagulant therapy or stent placement across the thrombosed vessel segment.

Cost-effectiveness of endovascular revascularization compared to supervised hospital-based exercise training in patients with intermittent claudication: a randomized controlled trial.

BACKGROUND: The optimal first-line treatment for intermittent claudication is currently unclear. OBJECTIVE: To compare the cost-effectiveness of endovascular revascularization vs supervised hospital-based exercise in patients with intermittent claudication during a 12-month follow-up period. DESIGN: Randomized controlled trial with patient recruitment between September 2002-September 2006 and a 12-month follow-up per patient. SETTING: A large community hospital. PARTICIPANTS: Patients with symptoms of intermittent claudication due to an iliac or femoro-popliteal arterial lesion (293) who fulfilled the inclusion criteria (151) were recruited. Excluded were, for example, patients with lesions unsuitable for revascularization (iliac or femoropopliteal TASC-type D and some TASC type-B/C. INTERVENTION: Participants were randomly assigned to endovascular revascularization (76 patients) or supervised hospital-based exercise (75 patients). MEASUREMENTS: Mean improvement of health-related quality-of-life and functional capacity over a 12-month period, cumulative 12-month costs, and incremental costs per quality-adjusted life year (QALY) were assessed from the societal perspective. RESULTS: In the endovascular revascularization group, 73% (55 patients) had iliac disease vs 27% (20 patients) femoral disease. Stents were used in 46/71 iliac lesions (34 patients) and in 20/40 femoral lesions (16 patients). In the supervised hospital-based exercise group, 68% (51 patients) had iliac disease vs 32% (24 patients) with femoral disease. There was a non-significant difference in the adjusted 6- and 12-month EuroQol, rating scale, and SF36-physical functioning values between the treatment groups. The gain in total mean QALYs accumulated during 12 months, adjusted for baseline values, was not statistically different between the groups (mean difference revascularization versus exercise 0.01; 99% CI -0.05, 0.07; P = .73). The total mean cumulative costs per patient was significantly higher in the revascularization group (mean difference euro2318; 99% CI 2130 euros, 2506 euros; P < .001) and the incremental cost per QALY was 231 800 euro/QALY adjusted for the baseline variables. One-way sensitivity analysis demonstrated improved effectiveness after revascularization (mean difference 0.03; CI 0.02, 0.05; P < .001), making the incremental costs 75 208 euro/QALY. CONCLUSION: In conclusion, there was no significant difference in effectiveness between endovascular revascularization compared to supervised hospital-based exercise during 12-months follow-up, any gains with endovascular revascularization found were non-significant, and endovascular revascularization costs more than the generally accepted threshold willingness-to-pay value, which favors exercise.

Long-term outcome of a covered vs. uncovered transjugular intrahepatic portosystemic shunt in Budd-Chiari syndrome.

BACKGROUND: The clinical outcome of a covered vs. uncovered transjugular intrahepatic portosystemic shunt (TIPS) for patients with Budd-Chiari syndrome (BCS) is as yet largely unknown. OBJECTIVES: To compare patency rates of bare and polytetrafluoroethylene (PTFE)-covered stents, and to investigate clinical outcome using four prognostic indices [Child-Pugh score, Rotterdam BCS index, modified Clichy score and Model for End-Stage Liver Disease (MELD)]. METHODS: Consecutive patients with BCS who had undergone TIPS between January 1994 and March 2006 were evaluated in a retrospective review in a single centre. RESULTS: Twenty-three TIPS procedures were performed on 16 patients. The primary patency rate at 2 years was 12% using bare and 56% using covered stents (P=0.09). We found marked clinical improvement at 3 months post-TIPS as determined by a drop in median Child-Pugh score (10-7, P=0.04), Rotterdam BCS index (1.90-0.83, P=0.02) and modified Clichy score (7.77-2.94, P=0.003), but not in MELD (18.91-17.42, P=0.9). Survival at 1 and 3 years post-TIPS was 80% (95% CI: 59-100%) and 72% (95% CI: 48-96%). Four patients (25%) died and one required liver transplantation. CONCLUSIONS: A transjugular intrahepatic portosystemic shunt using PTFE-covered stents shows better patency rates than bare stents in BCS. Moreover, TIPS leads to an improvement in important prognostic indicators for the survival of patients with BCS.

Multicenter randomized controlled trial of the costs and effects of noninvasive diagnostic imaging in patients with peripheral arterial disease: the DIPAD trial.

OBJECTIVE: The purpose of our study was to compare the costs and effects of three noninvasive imaging tests as the initial imaging test in the diagnostic workup of patients with peripheral arterial disease. MATERIALS AND METHODS: Of 984 patients assessed for eligibility, 514 patients with peripheral arterial disease were randomized to MR angiography (MRA) or duplex sonography in three hospitals and to MRA or CT angiography (CTA) in one hospital. The outcome measures included the clinical utility, functional patient outcomes, quality of life, and actual diagnostic and therapeutic costs related to the initial imaging test during 6 months of follow-up. RESULTS: With adjustment for potentially predictive baseline variables, the learning curve, and hospital setting, a significantly higher confidence and less additional imaging were found for MRA and CTA compared with duplex sonography. No statistically significant differences were found in improvement in functional patient outcomes and quality of life among the groups. The total costs were significantly higher for MRA and duplex sonography than for CTA. CONCLUSION: The results suggest that both CTA and MRA are clinically more useful than duplex sonography and that CTA leads to cost savings compared with both MRA and duplex sonography in the initial imaging evaluation of peripheral arterial disease.

Sirolimus-eluting stents to abolish intimal hyperplasia and improve flow in porcine arteriovenous grafts: a 4-week follow-up study.

BACKGROUND: The patency of arteriovenous (AV) expanded polytetrafluoroethylene (ePTFE) hemodialysis grafts is severely compromised by intimal hyperplasia (IH) at the venous anastomosis and in the venous outflow tract. We addressed the potential of primary placement of a sirolimus-eluting stent (SES) in a validated porcine model. METHODS AND RESULTS: In 25 pigs, ePTFE AV grafts were created bilaterally between the carotid artery and the jugular vein, whereupon a self-expandable nitinol stent (14 SESs and 11 bare-metal stents) was implanted over the venous anastomosis in 1 of the 2 grafts. After exclusion of technical failures and 1 unilateral occlusion, 16 pigs (9 SESs and 7 bare-metal stents) were included for further analysis. After 28 days, we measured graft flow and performed quantitative angiography. The pigs were then euthanized, and grafts with adjacent vessels were excised for histological analysis. Minimal luminal diameter was substantially larger in the SES group compared with unstented controls (5.9+/-0.2 versus 3.8+/-0.4 mm, respectively, P=0.01), which was accompanied by more prominent graft flow (SES, 1360+/-89 mL/min versus unstented, 861+/-83 mL/min, P=0.05). IH at the venous anastomosis was 77% less in the SES group compared with unstented controls (0.44+/-0.05 versus 1.92+/-0.5 mm2, respectively, P=0.01), whereas IH increased markedly when bare-metal stents were used (5.7+/-1.4 mm2, P=0.05). CONCLUSIONS: SESs in the venous outflow of AV grafts significantly reduce IH and increase vessel diameter and graft flow compared with unstented grafts. These findings suggest that SESs have the potential to improve primary patency of AV grafts in hemodialysis patients.

Reliable noninvasive coronary angiography with fast submillimeter multislice spiral computed tomography.

BACKGROUND: Multislice spiral computed tomography (MSCT) is a promising technique for noninvasive coronary angiography, although clinical application has remained limited because of frequently incomplete interpretability, caused by motion artifacts and calcifications. METHODS AND RESULTS: In 59 patients (53 male, aged 58+/-12 years) with suspected obstructive coronary artery disease, ECG-gated MSCT angiography was performed with a 16-slice MSCT scanner (0.42-s rotation time, 12x0.75-mm detector collimation). Thirty-four patients were given additional beta-blockers (average heart rate: 56+/-6 min(-1)). After contrast injection, all data were acquired during an approximately 20-s breath hold. The left main (LM), left anterior descending (LAD), left circumflex (LCX), and right coronary artery (RCA), including > or =2.0-mm side branches, were independently evaluated by two blinded observers and screened for > or =50% stenoses. The consensus reading was compared with quantitative coronary angiography. MSCT was successful in 58 patients. Eighty-six of the 231 evaluated branches were significantly diseased. Without exclusion of branches, the sensitivity, specificity and positive and negative predictive value to identify > or =50% obstructed branches was 95% (82/86), 86% (125/145), 80% (82/102), and 97% (125/129), respectively. The overall accuracy for the LM, LAD, RCA, and LCX was 100%, 91%, 86%, and 81%, respectively. No obstructed LM, LAD, or RCA branches remained undetected. Classification of patients as having no, single, or multivessel disease was accurate in 78% (45/58) of patients and no patients with significant obstructions were incorrectly excluded. CONCLUSIONS: Improvements in MSCT technology, combined with heart rate control, allow reliable noninvasive detection of obstructive coronary artery disease.

Multislice spiral computed tomography coronary angiography in patients with stable angina pectoris.

OBJECTIVES: This study was designed to prospectively evaluate the diagnostic performance of multislice spiral computed tomography (MSCT) coronary angiography for the detection of significant lesions in all segments of the coronary tree potentially suitable for revascularization. BACKGROUND: Noninvasive MSCT coronary angiography is a promising coronary imaging technique. METHODS: Sixteen-row MSCT coronary angiography was performed in 128 patients (89% men, mean age 58.9 +/- 11.7 years) in sinus rhythm with stable angina pectoris scheduled for conventional coronary angiography. Sixty percent (77 of 128) of patients received pre-scan oral beta-blockers, resulting in a mean heart rate of 57.7 +/- 7.7 beats/min. The diagnostic performance of MSCT for detection of significant lesions (> or =50% diameter reduction) was compared with that of quantitative coronary angiography (QCA). RESULTS: The sensitivity of MSCT for detection of significant lesions was 92% (216 of 234, 95% confidence interval [CI]: 88 to 95). Specificity was 95% (1,092 of 1,150, 95% CI: 93 to 96), positive predictive value 79% (216 of 274, 95% CI: 73 to 88), and negative predictive value 98% (1,092 of 1,110, 95% CI: 97 to 99). Two > or =50% lesions were missed because of motion artifacts and two because of severe coronary calcifications. The rest (78%, 14 of 18) were detected but incorrectly classified as <50% obstructions. All patients with and 86% (18 of 21) of patients without significant lesions on QCA were correctly classified by MSCT. All patients with significant left main disease or total occlusions were correctly identified on MSCT. CONCLUSIONS: Sixteen-row MSCT coronary angiography permits reliable detection of significant obstructive coronary artery disease in patients with stable angina in sinus rhythm.

Carotid plaque composition and cerebral infarction: MR imaging study.

BACKGROUND AND PURPOSE: Besides the severity of carotid artery stenosis, atherosclerotic plaque composition is an important determinant of cerebral symptoms. We analyzed the relationship between the composition of the atherosclerotic plaque at the carotid artery bifurcation and ipsilateral ischemic cerebral lesions on MR imaging. METHODS: Forty-one patients with symptomatic carotid artery stenosis (>70%) underwent black-blood, fast spin-echo imaging of the carotid artery and turbo fluid-attenuated inversion recovery (t-FLAIR) imaging of the brain. Plaque regions with a relative decrease in signal intensity in the plaque from proton density-weighted (TE = 14 ms) to T2-weighted (TE = 50 ms) imaging were considered to be lipid cores. We assessed the number and location of infarcts in the ipsilateral cortex, basal ganglia, and centrum semiovale, and hyperintense white matter lesions on t-FLAIR images. RESULTS: Lipid in the atherosclerotic plaque at the carotid bifurcation was seen in 25 patients. Ipsilateral infarctions were seen in 22 (54%); most often, it involved the centrum semiovale. Patients with a lipid core had an ipsilateral infarct more often than patients without a lipid core (68% vs. 31%; P = .03). Centrum semiovale infarcts were more frequent (56% vs. 25%, P = .06) and the median number of centrum semiovale infarcts was higher P = .04) in patients with a lipid core than in patients without a lipid core. CONCLUSION: Ischemic cerebral lesions were common in patients with symptomatic carotid artery disease. Plaque composition, as assessed with MR imaging, is related to the presence and extent of ischemic cerebral lesions.

Hemodialysis access graft failure: time to revisit an unmet clinical need?

Hemodialysis (HD) access complications constitute a major cause of morbidity in HD patients. The failure of HD access grafts is predominantly due to progressive intimal hyperplasia (IH) at the venous anastomosis, resulting in a graft flow decline, which ultimately gives rise to graft thrombosis. To date, all tested pharmacological and surgical interventions have not resulted in increased arteriovenous (AV) graft patency rates in HD patients. In this review, we address the mechanisms contributing to AV graft failure and discuss several "emerging" strategies, which could hold promise for optimizing AV graft patency rates. In view of the failure of systemic therapies and the predictable localization of IH, local therapeutic strategies comprise the most promising interventions to improve AV graft patency rates. Based on the large number of promising candidates including drug-eluting stents and brachytherapy, the unmet clinical need for AV graft failure in HD patients is likely to be revisited in the very near future. The biggest challenge, however, remains to translate basic experimental findings into clinical benefits. Simultaneously, continuous efforts should be undertaken to increase the percentage of patients utilizing AV fistulas, which remains the best form of permanent vascular access (VA) for HD.

Single-detector helical computed tomography as the primary diagnostic test in suspected pulmonary embolism: a multicenter clinical management study of 510 patients.

BACKGROUND: Helical computed tomography (CT) is a readily available tool for diagnosing pulmonary embolism (PE); however, its role in the management of patients with clinically suspected PE has not been fully established. OBJECTIVE: To determine the effectiveness and safety of using helical CT of the pulmonary arteries as the primary diagnostic test in patients with suspected PE. DESIGN: Multicenter, prospective clinical outcome study. SETTING: Two academic hospitals and one large teaching hospital in the Netherlands. PATIENTS: 510 consecutive inpatients and outpatients with clinically suspected PE followed for 3 months. INTERVENTIONS: Patients underwent helical CT of the pulmonary arteries within 24 hours after presenting with signs and symptoms of PE. If CT results were normal or inconclusive, compression ultrasonography was performed on the same day as CT and repeated on days 4 and 7 if findings on the first compression ultrasonography were normal. When CT or compression ultrasonography results were positive for thromboembolism, anticoagulation was started. Anticoagulation was not started when results of CT were negative for PE or indicated an alternative diagnosis that explained the clinical signs and symptoms, or when results on serial compression ultrasonography were normal. MEASUREMENTS: Patients received instructions to report any symptoms or signs of PE or deep venous thrombosis (DVT) during the 3-month follow-up period. The authors performed compression ultrasonography or phlebography for suspected DVT and pulmonary angiography for suspected PE. RESULTS: Computed tomography identified PE in 124 of 510 patients (24.3%) and an alternative diagnosis in 130 patients (25.5%); CT scans were normal in 248 patients (48.6%). The CT scan could not be interpreted in 8 patients (1.6%) and was not obtained in 2. Compression ultrasonography revealed DVT in 2 patients at the first examination; findings on repeated compression ultrasonography at days 4 and 7 were normal. Mortality in the patients with normal helical CT scans was 4.1% (10 of 246 patients). No patients in this group died of fatal PE, 1 patient developed nonfatal PE, and venous thromboembolism occurred in 0.4% of these patients (95% CI, 0% to 2.2%). In the patients with alternative diagnoses, 1 patient had DVT on objective testing during follow-up. Mortality in this group was 21.5% (28 of 130 patients); in 1 of these patients, PE could not be confidently ruled out as a contributing cause of death. Venous thromboembolism occurred in 1.5% of these patients (CI, 0.2% to 5.6%). CONCLUSIONS: In patients with suspected PE, helical CT can be used safely as the primary diagnostic test to rule out PE. Serial compression ultrasonography has limited additional value.

A biplane angiographic study on cardiac motion of coronary artery stents: options to minimize the target volume for high-precision external beam radiotherapy of coronary artery in-stent restenosis.

PURPOSE: High-precision external beam radiotherapy (EBRT) has been suggested as a potential alternative to endovascular brachytherapy for the treatment of coronary artery in-stent restenosis. The purpose of our study was to investigate and compare different options to define a smallest feasible target volume. METHODS AND MATERIALS: The cardiac motion of 17 coronary artery stents in 17 patients was studied by use of biplane conventional angiography, recorded during breath-hold. Each stent was reconstructed in three dimensions by use of biplane sets of frames covering an entire cardiac cycle. The volume traversed by the stent during the entire or part of the cardiac cycle was determined. Four options to define the stent-traversed volume (STV) as a target for high-precision EBRT were investigated. RESULTS: The mean STV during the entire cardiac cycle was 3.5 cm3; the STV represented less than 1% of the heart volume in all patients. The STV during the diastolic and systolic phase resulted in a mean reduction of 26.6% and 29.1%, respectively, compared with the STV during the entire cardiac cycle. The smallest STV, measured during a 160-ms interval within the cardiac cycle, resulted in a mean maximal reduction of 75.9% compared with the STV during the entire cardiac cycle. CONCLUSIONS: The STV during the entire cardiac cycle represents a small potential target volume for high-precision EBRT. A significant reduction of this target volume is possible in case of definition during a selected interval within the cardiac cycle.