Evaluation of MR-safe bioptomes for MR-guided endomyocardial biopsy in minipigs: a potential radiation-free clinical approach.

BACKGROUND: Diagnostic accuracy of endomyocardial biopsy could improve if clinically safe magnetic resonance (MR)-compatible bioptomes were available. We explored two novel MR-compatible cardiac bioptomes for performance, safety, and clinical viability, employing in vivo minipig trials and phase-contrast synchrotron radiation computed microtomography (SRµCT). METHODS: Analysis of ex vivo obtained pig endomyocardial biopsies was performed using phase-contrast SRµCT and conventional two-dimensional histology. The technical performance was evaluated by measuring volume, inner and outer integrities, compression, and histological diagnostic value in 3 sets (6 per set) of biopsies for each experimental bioptome. The bioptomes were tested in vivo in 3 healthy minipigs per bioptome. The clinical feasibility was evaluated by procedural and cutting success as well as histological diagnostic value. RESULTS: The bioptome with the 'grind-grind' design achieved similar values to control in compression (p = 0.822), inner (p = 0.628), and outer (p = 0.507), integrities ex vivo. It showed a better performance in the in vivo real-time MRI setting demonstrating a higher cutting success (91.7%) than the 'grind-anvil' (86.2%) design. In both ex vivo and in vivo evaluations, the 'grind-grind' design displayed sufficient diagnostic value (83% and 95%). The 'grind-anvil' design showed adequate diagnostic value both ex vivo and in vivo (78% and 87.5%) but was not comparable to control according to the three-dimensional (3D) analysis. CONCLUSION: A novel MR-compatible bioptome was identified as plausible in a clinical setting. Additionally, SRµCT and subsequent 3D structural analysis could be valuable in the label-free investigation of myocardial tissue at a micrometer level. RELEVANCE STATEMENT: Implementation of MR-guided biopsy can improve animal studies on structural myocardial changes at any point in an experimental setup. With further improvements in guiding catheters, MR-guided biopsy, using the new bioptome, has a potential to increase quality and diagnostic accuracy in patients both with structural and inflammatory cardiomyopathies. KEY POINTS: • Novel MR-compatible bioptomes show promise for a clinical application. • SRµCT enabled detailed analysis of endomyocardial biopsies. • The bioptomes showed adequate in vivo performance without major complications.

Structured Reporting in Cross-Sectional Imaging of the Heart: Reporting Templates for CMR Imaging of Ischemia and Myocardial Viability and for Cardiac CT Imaging of Coronary Heart Disease and TAVI Planning. / Strukturierte Befundung in der Schnittbilddiagnostik des Herzens: Befundvorlagen für die Herz-MRT bezüglich Ischämie- und Vitalitätsdiagnostik sowie für die Herz-CT bezüglich Koronardiagnostik und Planung vor TAVI.

BACKGROUND: Structured reporting allows a high grade of standardization and thus a safe and unequivocal report communication. In the past years, the radiological societies have started several initiatives to base radiological reports on structured reporting rather than free text reporting. METHODS: Upon invitation of the working group for Cardiovascular Imaging of the German Society of Radiology, in 2018 an interdisciplinary group of Radiologists, Cardiologists, Pediatric Cardiologists and Cardiothoracic surgeons -all experts on the field of cardiovascular MR and CT imaging- met for interdisciplinary consensus meetings at the University Hospital Cologne. The aim of these meetings was to develop and consent templates for structured reporting in cardiac MR and CT of various cardiovascular diseases. RESULTS: Two templates for structured reporting of CMR in ischemia imaging and vitality imaging and two templates for structured reporting of CT imaging for planning Transcatheter Aortic Valve Implantation (TAVI; pre-TAVI-CT) and coronary CT were discussed, consented and transferred to a HTML 5/IHR MRRT compatible format. The templates were made available for free use on the website www.befundung.drg.de. CONCLUSION: This paper suggests consented templates in German language for the structured reporting of cross-sectional CMR imaging of ischemia and vitality as well as reporting of CT imaging pre-TAVI and coronary CT. The implementation of these templates is aimed at providing a constant level of high reporting quality and increasing the efficiency of report generation as well as a clinically based communication of imaging results. KEY POINTS: · Structured reporting offers a constant level of high reporting quality and increases the efficiency of report generation as well as a clinically based communication of imaging results.. · For the first time templates in German language for the structured reporting of CMR imaging of ischemia and vitality and CT imaging pre-TAVI and coronary CT are reported.. · These templates will be made available on the website www.befundung.drg.de and can be commented via strukturierte-befundung@drg.de.. ZITIERWEISE: · Soschynski M, Bunck AC, Beer M et al. Structured Reporting in Cross-Sectional Imaging of the Heart: Reporting Templates for CMR Imaging of Ischemia and Myocardial Viability and for Cardiac CT Imaging of Coronary Heart Disease and TAVI Planning. Fortschr Röntgenstr 2023; 195: 293 - 296.

Optimized definition of right ventricular dysfunction on computed tomography for risk stratification of pulmonary embolism.

OBJECTIVES: There is an ongoing discussion on the optimal right to left (RV/LV) diameter ratio threshold and the best definition of RV dysfunction on computed tomography pulmonary angiography (CTPA) for risk assessment of pulmonary embolism (PE). METHODS: On routine diagnostic CTPA, volumetric and diameter measurements (axial and reconstructed views) of the ventricles and reflux of contrast medium into the inferior vena cava (IVC) and hepatic veins were assessed in consecutive PE patients enrolled in a prospective single-center registry. In-hospital adverse outcome was defined as PE-related death, cardiopulmonary resuscitation, mechanical ventilation or catecholamine administration. RESULTS: Of 609 patients (median age, 69 [IQR, 56-77] years; 47 % male) included in the analysis, 68 patients (11.2 %) had an adverse outcome and 35 (5.7 %) died. While neither a RV/LV volume ratio ≥1.0 nor RV/LV diameter ratios ≥1.0 were able to predict an adverse outcome, higher thresholds increased specificity. Further, neither volumetric measurements nor reconstruction of images provided superior prognostic information compared to RV/LV ratios measured in axial planes. The combination of an axial RV/LV diameter ratio ≥1.5 with substantial reflux of contrast medium was present in 134 patients (22 %) and associated with the best prognostic performance to predict an adverse outcome in unselected (OR 3.7 [95 % CI, 2.0-6.6]) and normotensive (OR 2.8 [95 % CI, 1.1-6.7]) patients. CONCLUSION: A new definition of RV dysfunction (axial RV/LV diameter ratio ≥1.5 and substantial reflux of contrast medium to the IVC and hepatic veins) allows an optimized CTPA-based prediction of PE-related adverse outcome.

[Interventional management of secondary retentions after thoracic and abdominal trauma]. / Interventionelle Versorgung sekundärer Verhalte nach thorakalem und abdominellem Trauma.

BACKGROUND: Percutaneous treatment of secondary thoracic and abdominal retention formations after blunt or penetrating trauma now represents a standard interventional radiological procedure. Various supportive imaging procedures are available, whereby computed tomography is mostly the treatment of choice due to the high diagnostic sensitivity. OBJECTIVE: Based on clinical examples this review article gives an overview of the state of the art minimally invasive interventional treatment of secondary posttraumatic retention formations of the thorax and abdomen. The indications and contraindications are illustrated and typical techniques and access routes are described. MATERIAL AND METHODS: Besides the general introduction and technical part, the article is divided into the anatomical compartments thorax and abdomen and frequently asked questions are dealt with. CONCLUSION: After the study of this article you should have got to know and understand the indications for a minimally invasive approach, the possible techniques and necessary materials as well as the indications and contraindications.

Prognostic value of right atrial dilation in patients with pulmonary embolism.

AIMS: Right atrial (RA) dilation and stretch provide prognostic information in patients with cardiovascular diseases. We investigated the prevalence, confounding factors and prognostic relevance of RA dilation in patients with pulmonary embolism (PE). METHODS: Overall, 609 PE patients were consecutively included in a prospective single-centre registry between September 2008 and August 2017. Volumetric measurements of heart chambers were performed on routine non-electrocardiographic-gated computed tomography and plasma concentrations of mid-regional pro-atrial natriuretic peptide (MR-proANP) measured on admission. An in-hospital adverse outcome was defined as PE-related death, cardiopulmonary resuscitation, mechanical ventilation or catecholamine administration. RESULTS: Patients with an adverse outcome (11.2%) had larger RA volumes (median 120 (interquartile range 84-152) versus 102 (78-134) mL; p=0.013), RA/left atrial (LA) volume ratios (1.7 (1.2-2.4) versus 1.3 (1.1-1.7); p<0.001) and MR-proANP levels (282 (157-481) versus 129 (64-238) pmol·L-1; p<0.001) compared to patients with a favourable outcome. Overall, 499 patients (81.9%) had a RA/LA volume ratio ≥1.0 and a calculated cut-off value of 1.8 (area under the curve 0.64, 95% CI 0.56-0.71) predicted an adverse outcome, both in unselected (OR 3.1, 95% CI 1.9-5.2) and normotensive patients (OR 2.7, 95% CI 1.3-5.6). MR-proANP ≥120 pmol·L-1 was identified as an independent predictor of an adverse outcome, both in unselected (OR 4.6, 95% CI 2.3-9.3) and normotensive patients (OR 5.1, 95% CI 1.5-17.6). CONCLUSIONS: RA dilation is a frequent finding in patients with PE. However, the prognostic performance of RA dilation appears inferior compared to established risk stratification markers. MR-proANP predicted an in-hospital adverse outcome, both in unselected and normotensive PE patients, integrating different prognostic relevant information from comorbidities.

Effect of short-term smoking & L-arginine on coronary endothelial function assessed by cardiac magnetic resonance cold pressor testing: a pilot study.

BACKGROUND: The effect of smoking on coronary vasomotion has been investigated in the past with various imaging techniques in both short- and long-term smokers. Additionally, coronary vasomotion has been shown to be normalized in long-term smokers by L-Arginine acting as a substrate for NO synthase, revealing the coronary endothelium as the major site of abnormal vasomotor response. Aim of the prospective cohort study was to investigate coronary vasomotion of young healthy short-term smokers via magnetic resonance cold pressor test with and without the administration of L-Arginine and compare obtained results with the ones from nonsmokers. METHODS: Myocardial blood flow (MBF) was quantified with first-pass perfusion MRI on a 1.5 T scanner in healthy short-term smokers (N = 10, age: 25.0 ± 2.8 years, 5.0 ± 2.9 pack years) and nonsmokers (N = 10, age: 34.3 ± 13.6) both at rest and during cold pressor test (CPT). Smokers underwent an additional examination after administration of L-Arginine within a median of 7 days of the naïve examination. RESULTS: MBF at rest turned out to be 0.77 ± 0.30 (smokers with no L-Arginine; mean ± standard deviation), 0.66 ± 0.21 (smokers L-Arginine) and 0.84 ± 0.08 (nonsmokers). Values under CPT were 1.21 ± 0.42 (smokers no L-Arginine), 1.09 ± 0.35 (smokers L-Arginine) and 1.63 ± 0.33 (nonsmokers). In all groups, MBF was significantly increased under CPT compared to the corresponding rest examination (p < 0.05 in all cases). Additionally, MBF under CPT was significantly different between the smokers and the nonsmokers (p = 0.002). MBF at rest was significantly different between the smokers when L-Arginine was given and the nonsmokers (p = 0.035). CONCLUSION: Short-term smokers showed a reduced response to cold both with and without the administration of L-Arginine. However, absolute MBF values under CPT were lower compared to nonsmokers independently of L-Arginine administration.

Fully automated quantification of biventricular volumes and function in cardiovascular magnetic resonance: applicability to clinical routine settings.

BACKGROUND: Cardiovascular magnetic resonance (CMR) represents the clinical gold standard for the assessment of biventricular morphology and function. Since manual post-processing is time-consuming and prone to observer variability, efforts have been directed towards automated volumetric quantification. In this study, we sought to validate the accuracy of a novel approach providing fully automated quantification of biventricular volumes and function in a "real-world" clinical setting. METHODS: Three-hundred CMR examinations were randomly selected from the local data base. Fully automated quantification of left ventricular (LV) mass, LV and right ventricular (RV) end-diastolic and end-systolic volumes (EDV/ESV), stroke volume (SV) and ejection fraction (EF) were performed overnight using commercially available software (suiteHEART®, Neosoft, Pewaukee, Wisconsin, USA). Parameters were compared to manual assessments (QMass®, Medis Medical Imaging Systems, Leiden, Netherlands). Sub-group analyses were further performed according to image quality, scanner field strength, the presence of implanted aortic valves and repaired Tetralogy of Fallot (ToF). RESULTS: Biventricular automated segmentation was feasible in all 300 cases. Overall agreement between fully automated and manually derived LV parameters was good (LV-EF: intra-class correlation coefficient [ICC] 0.95; bias - 2.5% [SD 5.9%]), whilst RV agreement was lower (RV-EF: ICC 0.72; bias 5.8% [SD 9.6%]). Lowest agreement was observed in case of severely altered anatomy, e.g. marked RV dilation but normal LV dimensions in repaired ToF (LV parameters ICC 0.73-0.91; RV parameters ICC 0.41-0.94) and/or reduced image quality (LV parameters ICC 0.86-0.95; RV parameters ICC 0.56-0.91), which was more common on 3.0 T than on 1.5 T. CONCLUSIONS: Fully automated assessments of biventricular morphology and function is robust and accurate in a clinical routine setting with good image quality and can be performed without any user interaction. However, in case of demanding anatomy (e.g. repaired ToF, severe LV hypertrophy) or reduced image quality, quality check and manual re-contouring are still required.

Magnetic resonance cold pressor test to investigate potential endothelial dysfunction in patients suffering from type 1 diabetes.

BACKGROUND: In its course, diabetes impairs microvascular function through endothelial dysfunction. As the response of myocardial perfusion to sympathetic stimulation through cold is modulated by endothelium-related factors, an incipient endothelial dysfunction might be observed noninvasively by investigation of myocardial perfusion with a cold pressor test (CPT). This approach has been used in clinical MRI previously. PURPOSE: To assess endothelial function of patients suffering from type 1 diabetes by MR CPT. STUDY TYPE: Prospective cohort study. SUBJECTS: Twenty type 1 diabetics and 20 healthy volunteers. FIELD STRENGTH/SEQUENCE: 3T, dynamic contrast enhanced perfusion (steady-state free precession). ASSESSMENT: Absolute quantitative myocardial perfusion values at rest and under CPT. STATISTICAL TESTS: Kolmogorov-Smirnov test to determine normal distribution of the results. T-test for independent samples. RESULTS: Patients' mean myocardial perfusion was 0.68 cc/g/min at rest and 0.80 cc/g/min during CPT, respective values of 0.81 cc/g/min and 1.36 cc/g/min were found in healthy volunteers. Perfusion values differed significantly for CPT (P < 0.01) but not for resting conditions (P = 0.06). DATA CONCLUSION: This study demonstrated that endothelial function might be impaired in type 1 diabetes patients. This fosters the thesis that endothelial function may serve as an early biomarker for coronary artery disease in patients with type 1 diabetes while these patients are still clinically asymptomatic. LEVEL OF EVIDENCE: 2 Technical Efficacy: Stage 3 J. Magn. Reson. Imaging 2018;48:1595-1601.

Transarterial chemoembolization with drug-eluting beads versus conventional transarterial chemoembolization in locally advanced hepatocellular carcinoma.

PURPOSE: In hepatocellular carcinoma patients with large or multinodal tumors, where curative treatment options are not feasible, transarterial therapies play a major role. Transarterial chemoembolization (TACE) with drug-eluting beads (DEB-TACE) is a promising new approach due to higher intratumoral and lower systemic concentration of the chemotherapeutic agent compared to conventional TACE (cTACE). PATIENTS AND METHODS: In a retrospective analysis, 32 patients with hepatocellular carcinoma who received either DEB or a cTACE were compared regarding survival time, disease recurrence, and side effects such as pain and fever. RESULTS: No significant differences could be detected between the cTACE and DEB-TACE groups with regard to mean hospital stay, appearance of postinterventional fever, or 30-day mortality. However, the application of intravenous analgesics as postinterventional pain medication was needed more often in patients treated with DEB-TACE (57.1% vs 12.5%, P=0.0281). The overall median survival after the initial procedure was 10.8 months in the cTACE group and 9.2 months in the DEB-TACE group, showing no significant difference. CONCLUSION: No survival benefit for patients treated with either DEB-TACE or cTACE was observed. Surprisingly, a higher rate of postinterventional pain could be detected after DEB-TACE.

Left Ventricular Geometry and Blood Pressure as Predictors of Adverse Progression of Fabry Cardiomyopathy.

BACKGROUND: In spite of several research studies help to describe the heart in Fabry disease (FD), the cardiomyopathy is not entirely understood. In addition, the impact of blood pressure and alterations in geometry have not been systematically evaluated. METHODS: In 74 FD patients (mean age 36±12 years; 45 females) the extent of myocardial fibrosis and its progression were quantified using cardiac magnetic-resonance-imaging with late enhancement technique (LE). Results were compared to standard echocardiography complemented by 2D-speckle-tracking, 3D-sphericity-index (SI) and standardized blood pressure measurement. At baseline, no patient received enzyme replacement therapy (ERT). After 51±24 months, a follow-up examination was performed. RESULTS: Systolic blood pressure (SBP) was higher in patients with vs. without LE: 123±17 mmHg vs. 115±13 mmHg; P = 0.04. A positive correlation was found between SI and the amount of LE-positive myocardium (r = 0.51; P<0.001) indicating an association of higher SI in more advanced stages of the cardiomyopathy. SI at baseline was positively associated with the increase of LE-positive myocardium during follow-up. The highest SBP (125±19 mmHg) and also the highest SI (0.32±0.05) was found in the subgroup with a rapidly increasing LE (ie, ≥0.2% per year; n = 16; P = 0.04). Multivariate logistic regression analysis including SI, SBP, EF, left ventricular volumes, wall thickness and NT-proBNP adjusted for age and sex showed SI as the most powerful parameter to detect rapid progression of LE (AUC = 0.785; P<0.05). CONCLUSIONS: LV geometry as assessed by the sphericity index is altered in relation to the stage of the Fabry cardiomyopathy. Although patients with FD are not hypertensive, the SBP has a clear impact on the progression of the cardiomyopathy.

Computed tomography criteria for discrimination of adrenal adenomas and adrenocortical carcinomas: analysis of the German ACC registry.

OBJECTIVE: Thresholds of 2-20 hounsfield units (HU) in unenhanced computed tomography (CT) are suggested to discriminate benign adrenal tumors (BATs) from malignant adrenal tumors. However, these studies included only low numbers of adrenocortical carcinomas (ACCs). This study defines a HU threshold by inclusion of a large cohort of ACCs. DESIGN: Retrospective, blinded, comparative analysis of CT scans from 51 patients with ACCs (30 females, median age 49 years) and 25 patients with BATs (12 females, median age 64 years) diagnosed during the period of 2005-2010 was performed. METHODS: Tumor density was evaluated in unenhanced CT by two blinded investigators. RESULTS: Median tumor size was 9 cm (range 2.0-20) for ACCs vs 4 cm (2.0-7.5) for BATs (P<0.0001). In ACCs, the median unenhanced HU value was 34 (range 14-74) in comparison with 5 (-13 to 40) in BATs (P<0.0001). ROC analysis revealed a HU of 21 as threshold with the best diagnostic accuracy (sensitivity 96%, specificity 80%, and AUC 0.89). However, two ACCs that were 5 and 6 cm in size would have been missed. Setting the threshold to 13.9 allowed for 100% sensitivity, but a lower specificity of 68%. CONCLUSIONS: This first large study on ACCs confirmed that the vast majority of ACCs have unenhanced HU >21. However, to avoid misdiagnosing an ACC as benign, a threshold of 13 should be used.

SElf-gated Non-Contrast-Enhanced FUnctional Lung imaging (SENCEFUL) using a quasi-random fast low-angle shot (FLASH) sequence and proton MRI.

Obtaining functional information on the human lung is of tremendous interest in the characterization of lung defects and pathologies. However, pulmonary ventilation and perfusion maps usually require contrast agents and the application of electrocardiogram (ECG) triggering and breath holds to generate datasets free of motion artifacts. This work demonstrates the possibility of obtaining highly resolved perfusion-weighted and ventilation-weighted images of the human lung using proton MRI and the SElf-gated Non-Contrast-Enhanced FUnctional Lung imaging (SENCEFUL) technique. The SENCEFUL technique utilizes a two-dimensional fast low-angle shot (FLASH) sequence with quasi-random sampling of phase-encoding (PE) steps for data acquisition. After every readout, a short additional acquisition of the non-phase-encoded direct current (DC) signal necessary for self-gating was added. By sorting the quasi-randomly acquired data according to respiratory and cardiac phase derived from the DC signal, datasets of representative respiratory and cardiac cycles could be accurately reconstructed. By application of the Fourier transform along the temporal dimension, functional maps (perfusion and ventilation) were obtained. These maps were compared with dynamic contrast-enhanced (DCE, perfusion) as well as standard Fourier decomposition (FD, ventilation) reference datasets. All datasets were additionally scored by two experienced radiologists to quantify image quality. In addition, one initial patient examination using SENCEFUL was performed. Functional images of healthy volunteers and a patient diagnosed with hypoplasia of the left pulmonary artery and left-sided pulmonary fibrosis were successfully obtained. Perfusion-weighted images corresponded well to DCE-MRI data; ventilation-weighted images offered a significantly better depiction of the lung periphery compared with standard FD. Furthermore, the SENCEFUL technique hints at a potential clinical relevance by successfully detecting a perfusion defect in the patient scan. It can be concluded that SENCEFUL enables highly resolved ventilation- and perfusion-weighted maps of the human lung to be obtained using proton MRI, and might be interesting for further clinical evaluation.

Differentiation of an unclear splenic lesion in a patient with cholangiocarcinoma.

Here we report on a 51-year-old man with the primary diagnosis of cholangiocarcinoma. Workup with CT and contrast-enhanced ultrasound revealed an additional lesion in the spleen, raising the concern for metastasis. Combined FDG PET/CT revealed a different metabolic pattern, making a metastasis unlikely. Histopathology of the splenic lesion confirmed sclerosing angiomatoid nodular transformation, a rare benign lesion of the spleen.

Endovascular treatment of popliteal artery segments P1 and P2 in patients with critical limb ischemia: initial experience using a helical nitinol stent with increased radial force.

PURPOSE: To evaluate efficacy, safety, and midterm patency of a helical, self-expanding nitinol stent after failed percutaneous transluminal angioplasty (PTA) of popliteal artery segments P1 and P2 in patients with chronic critical limb ischemia (CLI) or lifestyle-limiting claudication. METHODS: Between February 2009 and March 2011, 40 patients (23 men; mean age 77±10 years) classified as Rutherford category 3 (n = 10) or 4/5 (n = 30) underwent PTA of the proximal and mid popliteal artery followed by implantation of a SUPERA stent for elastic recoil, residual stenosis, or flow-limiting dissection. All patients had an elevated operative risk. Before and after the procedure and during the 12-month follow-up, a clinical investigation, ankle-brachial-index (ABI) measurement, and color-coded duplex sonography and/or digital subtraction angiography were performed. Primary endpoints were limb salvage and anatomical patency at 12 months. RESULTS: Stent implantation was successful in all patients. The major complication rate was 7.5% (an access-site pseudoaneurysm, 2 retroperitoneal hematomas, and 1 death from retroperitoneal bleeding). Mean follow-up was 15.9 months (range 0.5-27.9). The mean baseline ABI of 0.37 significantly increased to 0.91 at 12 months (p<0.01). Three (7.5%) patients underwent bypass surgery owing to lack of clinical improvement (<0.10 improvement in ABI). Primary and secondary patency rates at 12 months in the 34 patients eligible for follow-up were 68.4% and 79.8%, respectively. The major amputation rate was 5% at 1 year. Five (12.5%) in-stent stenoses and 1 of 2 (5.0%) in-stent occlusions were successfully recanalized (the second occlusion was asymptomatic). CONCLUSION: Implantation of this helical stent into segments of the popliteal artery at the knee joint in CLI patients is a safe and clinically effective bailout method with acceptable intermediate patency.

Identification of risk factors for catheter-related thrombosis in patients with totally implantable venous access ports in the forearm.

PURPOSE: To identify risk factors for the development of catheter-related thrombosis (CRT) in patients with totally implantable venous access ports (TIVAP) in the forearm, and to analyze the effect of prophylaxis and treatment. METHODS: We retrospectively identified 200 patients (94 men, 106 women, mean age 57.7 +/-14 y) with TIVAP implantation in the forearm between 3/2010 and 11/2010. Type, number of punctures and sonographically defined diameter of the accessed vein were analyzed. Chemotherapy administered prior to the implantation procedure and history of thrombo-embolic events were assessed. Thrombo-embolic prophylaxis (TEP) following port implantation and treatment as well as course of CRT were analyzed. RESULTS: Twenty-one patients (10.5%) were diagnosed with CRT. Accessed vessels and mean diameter were basilic (n=150, 3.7 mm), brachial (n=39, 3.5 mm) and cephalic (n=11, 3.5 mm) vein. Neither type nor vessel diameter had effect on CRT development (P>.05). Implantation in the left forearm resulted in a significantly higher rate of CRT (P=.04). Ninety-five patients (47.5%) received chemotherapy and 30 patients (15.0%) had a history of thrombosis prior to implantation; both had no effect on development of CRT. Low molecular weight heparin (LMWH) was prescribed in 94/200 patients (47.0%) and had no effect on development of CRT (P>.05). Therapeutic anticoagulation with LMWH resulted in clinical improvement in 12/21 patients (57.4%). CONCLUSIONS: TIVAPs of the forearm may be associated with a certain rate of early and late CRT. The simplest vein to puncture should be selected for vascular access. Thrombo-embolic prophylaxis appears to be rather ineffective for prevention of CRT.

Comparison of intravascular and extracellular contrast media for absolute quantification of myocardial rest-perfusion using high-resolution MRI.

PURPOSE: To use the contrast agent gadofosveset for absolute quantification of myocardial perfusion and compare it with gadobenate dimeglumine (Gd-BOPTA) using a high-resolution generalized autocalibrating partially parallel acquisition (GRAPPA) sequence. MATERIALS AND METHODS: Ten healthy volunteers were examined twice at two different dates with a first-pass perfusion examination at rest using prebolus technique. We used a 1.5 T scanner and a 32 channel heart-array coil with a steady-state free precession (SSFP) true fast imaging with steady state precession (trueFISP) GRAPPA sequence (acceleration-factor 3). Manual delineation of the myocardial contours was performed and absolute quantification was performed after baseline and contamination correction. At the first appointment, 1cc/4cc of the extracellular contrast agent Gd-BOPTA were administered, on the second date, 1cc/4cc of the blood pool contrast agent (CA) gadofosveset. At each date the examination was repeated after a 15-minute time interval. RESULTS: Using gadofosveset perfusion the value (in cc/g/min) at rest was 0.66 ± 0.25 (mean ± standard deviation) for the first, and 0.55 ± 0.24 for the second CA application; for Gd-BOPTA it was 0.62 ± 0.25 and 0.45 ± 0.23. No significant difference was found between the acquired perfusion values. The apparent mean residence time in the myocardium was 23 seconds for gadofosveset and 19.5 seconds for Gd-BOPTA. Neither signal-to-noise ratio (SNR) nor subjectively rated image contrast showed a significant difference. CONCLUSION: The application of gadofosveset for an absolute quantification of myocardial perfusion is possible. Yet the acquired perfusion values show no significant differences to those determined with Gd-BOPTA, maintained the same SNR and comparable perfusion values, and did not picture the expected concentration time-course for an intravasal CA in the first pass.

Explantation of totally implantable venous access ports of the forearm: reasons for removal and observed complications.

PURPOSE: To evaluate indications for, and complications during, explantation of interventionally placed totally implantable venous access ports (TIVAPs) of the forearm. BACKGROUND: Many studies analyze the explantation procedure of pectorally placed TIVAPs. The literature on TIVAPs in the forearm is limited, and the explantation procedure of these devices in the forearm has not been sufficiently evaluated yet. METHODS: We retrospectively reviewed the archives of our institute between May 2006 and May 2009 and identified 850 TIVAPs that had been implanted in the forearm. Of these TIVAPs, 145/850 (80 in women, 65 in men; mean age 52 years, range 15-82 years) were explanted during this period either by interventionists (n=109) or by general surgeons (n=36). RESULTS: Mean catheter survival was 322 days. Reasons for explantation were end of therapy (63.4%), infection (29.0%), thrombosis (3.4%), occlusion (1.4%), or dislocation (1.4%) of the TIVAP. Primary technical success rate was 97.2% for the surgical as well as for the interventional procedure. The overall success rate was 100%. The reasons for retrieval failure by interventionists (3/108) as well as by surgeons (1/36) were post-thrombotic adhesions of the port catheter to the blood vessel wall. CONCLUSIONS: Removal of TIVAPs of the forearm shows a high technical success rate and a low complication rate. End of therapy is the most common indication for explantation. There is a low risk of interventional removal failure with a resulting need for open surgery to remove the device.

Endovascular treatment of acute limb ischemia secondary to fracture of a popliteal artery stent.

The authors report the case of a patient with acute lower limb ischemia (category IIa) after occlusion of the popliteal artery due to fracture of a long indwelling stent. The patient refused surgical therapy for religious reasons, and an interventional revascularization was performed as acute rescue therapy. After reentry into the distal popliteal artery was achieved, the artery was dilated, and the fragmented stent was crushed, followed by implantation of two helical nitinol stents with high radial force and a third self-expandable nitinol stent. Sufficient primary technical success was achieved, and stent patency was present at midterm follow-up.