Radiofrequency-induced thermotherapy (RFiTT) in a porcine liver model and ex vivo great saphenous vein

Aims: To investigate the thermal spread achieved in porcine liver when using an optimised radiofrequency ablation protocol and correlate findings with the effects seen in ex vivo great saphenous vein (GSV), in order to justify clinical use with the new treatment protocol.

Material and methods: Porcine liver and GSV sections were treated with radiofrequency-induced thermotherapy (RFiTT) using the following settings: 20 W at 1?s/cm (linear endovenous energy density; LEED 20 J/cm), 18 W at 1?s/cm (LEED 18 J/cm), 18 W at 3?s/cm (LEED 54 J/cm), 6 W interrupted pull-back 6?s stationary every 0.5?cm (LEED 72 J/cm). Thermal spread in the liver was measured via digital imaging. GSV sections were sent to an independent laboratory for histological analysis. Previous work suggests a thermal spread of?>0.65?mm in liver correlates with transmural thermoablation of a GSV.

Results: Parameters giving a LEED of 72 J/cm produced the best results, with a clear transmural effect in the GSV and maximal thermal spread of 1.65?mm, without excessive thermal damage or carbonisation in the ablation tract.

Conclusions: Our porcine liver model correlated well with histological findings and was representative of the thermoablative effects observed in the GSV wall treated with RFiTT. Clinical investigations are now being carried out to investigate the efficacy of this protocol in the clinical setting.     

超声引导下注射泡沫硬化剂治疗大隐静脉曲张

目的 探讨超声引导下注射泡沫硬化剂治疗大隐静脉曲张的临床疗效.方法 无深静脉及穿静脉功能不全的中、重度大隐静脉曲张40条患肢(38例患者,2例为双侧下肢大隐静脉曲张),在超声引导下注射泡沫硬化剂Fibro-Vein对隐股交界处下方10 cm处及其以远的大隐静脉主干进行硬化治疗.结果 40条患肢均在超声引导下注射治疗成功,其中7条(7/40)大隐静脉于治疗后1个月复诊时实施了第2次注射治疗.平均随访40个月(30～47个月).2条肢体失访.2条患肢尚存轻微乏力,所有患肢其他症状均消失.无严重并发症.根据超声检查大腿段静脉情况可分4种类型:Ⅰ型,84.2%(32/38),大隐静脉主干全程或部分管段实变、无血流;Ⅱ型,7.9%(3/38),大隐静脉主干管腔仍存在,其中2条尚存少量反流;Ⅲ型,2.6%(1/38),大隐静脉主干实变,其属支股外侧浅静脉少量反流;Ⅳ型,5.3%(2/38),大隐静脉主干近段实变,远段与另一条浅表静脉相连并少量反流.结论 超声引导下注射泡沫硬化剂治疗大隐静脉曲张疗效满意,为一种治疗与美容兼备的微创治疗方法.     

Diameter and compliance of the greater saphenous vein - effect of age and nitroglycerine

Objectives: The greater saphenous vein (GSV) is commonly used in autologous vein graft surgery. GSV diameter has proven to influence graft patency, and furthermore venous compliance might be of importance. The purpose of the study was to evaluate the effect of age on GSV diameter and compliance, and to evaluate the effect of nitroglycerine (NTG). Methods: The diameter and compliance of the GSV, with and without NTG, were examined with B‐mode ultrasound in 12 elderly (70·3 ± 1·2 year) and 15 young (25·1 ± 0·6 year) men. The GSV diameter at the thigh and calf level was measured at rest, after 6 min of venous stasis (60 mmHg) and after NTG administration. Pressure–area curves during a linear venous pressure decrease were produced. Venous compliance was calculated using the quadratic regression equation (area) = β₀ + β₁ (cuff pressure) + β₂ (cuff pressure)². Results: GVS diameter between the groups showed significant lower diameter in elderly compared to young men (P<0·05). Venous occlusion increased GSV diameter in elderly men (P<0·01) as well as young men (P<0·001). NTG increased GSV diameter in elderly men (P<0·01) with an equal trend in young men. During venous occlusion, after administration of NTG, GSV diameter increased further in both elderly (P<0·01) and young men (P<0·001). GSV compliance was decreased in elderly (β₁, 0·037 ± 0019, β_2,?0·000064 ± 00017) versus young men (β₁, 0·128 ± 0·013, β₂, ?0·00010 ± 000018) [P<0·001 (β₁), P<0·02 (β₂)]. Conclusions: Baseline GSV diameter as well as GSV compliance is decreased in elderly men compared to the young subjects. As reduced GSV diameter as well as reduced compliance is related to decreased graft patency, these findings might be of importance for the uses of GSV as graft material in cardiovascular bypass surgery. The clinical value has to be clarified in future studies.     

超声评价正常小儿肝脏血管的内径及血流动力学

目的 通过超声检查获取正常小儿肝脏血管的内径及血流动力学参数测值.方法 对213名正常小儿进行二维及多普勒超声检查,测量肝动脉的内径及阻力指数(RI)、搏动指数(PI),门静脉主干及分支的内径、血流速度、血流量.测量数据进行相邻年龄组间比较.结果 肝动脉的内径随着年龄的增长而增加且相邻组间差异有统计学意义,R1和PI则是相对较恒定的参数.门静脉主干及分支的内径及血流量随着年龄的增长而递增,但增幅减小,幼儿期增长最明显.门静脉主干及分支的血流速呈现随年龄增长增高后有回落的趋势.结论 小儿肝脏血管的内径及血流动力学随其生长发育也在不断变化,其增长的特点与小儿生长发育特点相吻合.     

腔内射频闭合术治疗大隐静脉曲张3年超声随访结果

目的观察超声引导下腔内射频闭合术治疗大隐静脉曲张的3年临床疗效。方法对6例大隐静脉曲张患者的6条无深静脉及穿静脉功能不全的中至重度大隐静脉曲张患肢，在超声引导下行腔内射频闭合大隐静脉主干，术后2—4周及术后3年对治疗下肢行超声随访。结果6条曲张的大隐静脉均成功实施腔内射频闭合术，术后2—4周随访，患者下肢酸痛、酸胀、乏力和浅表静脉曲张均减轻；超声检查6条大隐静脉主干均闭塞，无反流。术后3年随访，除1例尚有轻度下肢乏力外，其余患者症状消失；超声检查发现5条治疗段大隐静脉主干部分或全部管段呈条索状实变，直径小于2．0mm，另一条大隐静脉主干明显变细，内径3．0mm，有少量反流信号。结论超声引导下腔内射频闭合术治疗大隐静脉曲张术后3年随访结果佳，值得进一步研究。     

Simple external rotation of the leg increases the size and accessibility of the femoral vein

Objective: To determine if external rotation of the leg increases the size and accessibility of the femoral vein compared with a neutral position. Methods: One hundred patients presenting to a tertiary teaching hospital were prospectively recruited. The right common femoral vein of each subject was scanned with a linear probe (5–10 MHz) inferior to the inguinal ligament, with the leg in a neutral position and then in the externally rotated position. The transverse diameter of the femoral vein, the accessible diameter of the vein (lying medial to the femoral artery) and the depth of the vein were measured. Results: The mean diameter of the femoral vein in the externally rotated leg was greater than with the leg in the neutral position (15.4 mm vs 13.8 mm); the mean difference was 1.6 mm (95% CI 1.3–1.9). The mean accessible diameter of the femoral vein was larger with the leg externally rotated (13.8 mm vs 11.7 mm, mean difference 2.1 mm, 95% CI 1.8–2.5). The depth from the skin to the femoral vein was less with the leg in external rotation (20.9 mm vs 22.6 mm, mean difference 1.7 mm, 95% CI 1.2–2.2). The mean diameter and depth were greater in patients with overweight or obese body mass index (BMI) measurements in both leg positions. The increase in femoral vein diameter and accessibility with external rotation was observed in all BMI groups. Conclusion: The total and accessible femoral vein diameter is increased and the surface depth of the vein is decreased by placing the leg in external rotation compared with the neutral position.     

门静脉海绵样变性左支分流手术前后的超声应用

目的探讨超声评估门静脉海绵样变性合并门静脉高压症患儿门静脉左支分流手术（Rex手术）疗效的价值。方法选取2014年10月~2016年1月在我院因门静脉海绵样变性合并门静脉高压症行Rex手术的患儿10例,手术前、后二维超声分别测量肝脏、脾脏各个径线值并计算其大小变化,测量手术前后门静脉左支、术后桥血管及吻合口内径,多普勒超声评价门静脉左支、桥血管及吻合口的血流通畅情况。结果10例患儿Rex术后门静脉海绵样变性病变区域血流信号显著减少;术前肝右叶斜径、肝左叶上下径、脾脏面积分别为98.5±3.5 mm、53.3±2.7 mm、42.9±5.9 cm2,其中,术后1周的肝右叶斜径（109.3±1.9 mm）以及术后1年的肝右叶斜径（108.7±1.0 mm）、左叶上下径（64.0±2.5 mm）、脾脏面积（28.5±3.6 cm2）较术前的差异均有统计学意义（P<0.05）。术后门静脉左支、门静脉左支吻合口超声显示清晰,显示率为100%,肠系膜上静脉吻合口显示率为70%。术前门静脉左支内径为2.58±0.34 mm,术后门静脉左支内径为5.33±0.61 mm（术后6月）、6.90±0.95 mm（术后1年）,较术前差异均有统计学意义（P<0.05）;术后1周、3月、6月、1年的相关血管内径如下:桥血管:5.96±0.80、6.90±0.68、7.41±0.56 mm;门静脉左支吻合口:2.77±0.37、2.71±0.36、3.53±0.32 mm;肠系膜上静脉吻合口:3.26±0.16、3.40±0.17、3.63±0.11 mm。结论超声可无创、定量评估Rex手术前后肝脏和脾脏大小、门静脉左支,术后桥血管、吻合口内径,评估术后门静脉左支、桥血管及吻合口的血流状态,为手术效果的评估提供可靠指标。      

Evaluation of left gastric vein in Chinese healthy adults with multi-detector computed tomography

Objectives: To evaluate the classification and diameter of left gastric vein (LGV) in healthy Chinese adults with multi-detector computed tomography (MDCT).

Methods: MDCT angiography was performed in 234 healthy adults for the portal venous system. CT cross-sectional thin-layer reconstruction combined with maximum intensity projection, volume rendering and multiplanar reconstruction were applied. The diameter of LGV was measured at the point within 2 cm from LGV origination.

Results: Of 234 subjects, 11 subjects (4.70%) who did not have clear images were excluded, and 223 subjects (95.30%) with excellent images were included. The LGV was originated from the portal vein in 46.15%, splenic vein in 30.77%, portal splenic angle in 14.53%, and the left branch of the portal vein in 3.85%. The maximal diameter of LGV was 4.74 ± 0.84 mm with a 95% confidence interval of 4.63–4.85 mm, and the LGV diameter was positively correlated with the weight of patients (R = 0.26, P = 0.006). No significant difference existed in the maximal diameter of LGV at different origination sites (P = 0.35). The diameter of LGV was significantly greater in males than in females (4.90 ± 0.85 vs. 4.56 ± 0.80 mm, P = 0.002), and the maximal diameter of LGV was significantly (P = 0.02) greater in the age range of 30–39 and 40–49 years than in the range of >70 years. No statistical significance (P = 0.36) was detected in the other groups.

Conclusion: MDCT can clearly display the detailed anatomy and variation of LGV in healthy adults, providing a normal range of LGV diameter for clinical reference for diagnosing possible portal hypertension and for possible intervention.     

Saphenous vein ablation with a new cyanoacrylate glue device: a systematic review on 1000 cases

Background: To review published evidence regarding an n-butyl-cyanoacrylate (NBCA) injection device for great (GSV) and small (SSV) saphenous vein incompetence in terms of occlusion rate, postoperative complications and quality of life improvement.

Material and methods: International bibliographic databases (PubMed, EMBASE, Scopus) were searched to identify possible target articles. The only inclusion criterion was the use of the Variclose^® system (Biolas, Ankara, Turkey) for superficial vein insufficiency. Exclusion criteria were case reports, review, meta-analysis, article with <6-month follow-up data, abstracts and congress presentations. PRISMA guidelines were used to lead articles selection.

Results: Seven studies were included in the final data analysis. A total of 918 patients (1000 limbs) underwent an NBCA procedure for GSV (947 cases) or SSV (53 cases) incompetence. The average procedure duration was 11.7?min. The most common postoperative complications were postoperative pain (4.8%) and superficial vein thrombosis (2.1%). No deep vein thrombosis or pulmonary embolism cases were described. The occlusion rates at six, 12 and 30?months were 97.3%, 96.8% and 94.1%, respectively.

Conclusion: NBCA injection with the Variclose device seems to be a feasible, effective and safe treatment in GSV incompetence. Long-term follow-up studies and randomized controlled trials are needed to achieve high-quality evidence.     

Headless compression screw for horizontal medial malleolus fractures

BackgroundHorizontal medial malleolus fractures are caused by the application of rotational force through the ankle joint in several orientations. Multiple techniques are available for the fixation of medial malleolar fractures.MethodsHorizontal medial malleolus osteotomies were performed in eighteen synthetic distal tibiae and randomized into two fixation groups: 1) two parallel unicortical cancellous screws or 2) two Acutrak 2 headless compression screws. Specimens were subjected to offset axial tension loading. Frontal plane interfragmentary motion was monitored.FindingsThe headless compression group (1699 (SD 947) N/mm) had significantly greater proximal-distal stiffness than the unicortical group (668 (SD 298) N/mm), (P = 0.012). Similarly, the headless compression group (604 (SD 148) N/mm) had significantly greater medial-lateral stiffness than the unicortical group (281 (SD 152) N/mm), (P < 0.001). The force at 2 mm of lateral displacement was significantly greater in the headless compression group (955 (SD 79) N) compared to the unicortical group (679 (SD 198) N), (P = 0.003). At 2 mm of distal displacement, the mean force was higher in the headless compression group (1037 (SD 122) N) compared to the unicortical group (729 (SD 229) N), but the difference was not significant (P = 0.131).InterpretationA headless compression screw construct was significantly stiffer in both the proximal-distal and medial-lateral directions, indicating greater resistance to both axial and shear loading. Additionally, they had significantly greater load at clinical failure based on lateral displacement. The low-profile design of the headless compression screw minimizes soft tissue irritation and reduces need for implant removal.     

Application of transmesenteric vein extrahepatic portosystemic shunt in treatment of symptomatic portal hypertension with cavernous transformation of portal vein

Purpose: To evaluate the feasibility and efficacy of a transmesenteric vein extrahepatic portosystemic shunt(TmEPS) for the treatment of cavernous transformation of the portal vein(CTPV).Materials and methods: The clinical data of 20 patients with CTPV who underwent TmEPS between December 2020and January 2022 at Henan Provincial People’s Hospital were retrospectively collected. The superior mesenteric vein(SMV) trunk was patent or partially occluded in these patients. An extrahepatic portosystem...     

The effect of radial head prosthesis diameter on posterolateral rotatory instability of the elbow

BackgroundThe purpose of this study is to investigate how different diameters of radial head replacement affect posterolateral translation with a valgus and supination force. We hypothesized that there would be less posterolateral rotatory translation with larger implant diameter.MethodsEleven cadaveric arms were stressed at 30 and 60° of flexion with a consistent supination and valgus stress force under five conditions: native radial head, radial head excision, and with 3 sizes of radial head prosthesis. Displacement of the radial head posteriorly in relation to the capitellum on radiographs was measured. Displacement was expressed as a percentage relative to the average of the maximum and minimum native radial head diameters.FindingsThe native radial heads had average minimum and maximum diameters of 23.3 mm and 25.2 mm, respectively. The angle of testing did not significantly change translation of the radial head. There was increased posterior translation relative to native head as the radial head sizes decreased from 24 mm to 20 mm and with excision of the radial head. Compared to the native head, the differences in displacement were statistically significant for the 20 mm radial head, but not for the 22 mm or 24 mm replacements. Radial head translation significantly increased after radial head excision.InterpretationsThis cadaveric study illustrates that patients treated with radial head excision and radial head prosthesis with undersized diameters have increased posterior translation with a valgus and supination stress. The larger the radial head prosthesis (closer to native radial head), the more closely it approximated the amount of translation of the native radial head.     

Splenorenal shunt via magnetic compression technique: a feasibility study in canine and cadaver

Introduction: The concept of magnetic compression technique (MCT) has been accepted by surgeons to solve a variety of surgical problems. In this study, we attempted to explore the feasibility of a splenorenal shunt using MCT in canine and cadaver.

Material and methods: The diameters of the splenic vein (SV), the left renal vein (LRV), and the vertical interval between them, were measured in computer tomography (CT) images obtained from 30 patients with portal hypertension and in 20 adult cadavers. The magnetic devices used for the splenorenal shunt were then manufactured based on the anatomic parameters measured above. The observation of the anatomical structure showed there were no special structural tissues or any important organs between SV and LRV. Then the magnetic compression splenorenal shunt procedure was performed in three dogs and five cadavers. Seven days later, the necrotic tissue between the two magnets was shed and the magnets were removed with the anchor wire.

Results: The feasibility of splenorenal shunt via MCT was successfully shown in both canine and cadaver, thus providing a theoretical support for future clinical application.     

Extrahepatic bile ducts in healthy subjects,in patients with cholelithiasis,and in postcholecystectomy patients: A prospective ultrasonic study

To determine the average diameter and the upper normal limit of the common bile duct in healthy man, 830 blood donors were examined by ultrasound. The mean diameter was 2.5 ± 1.1 mm (SD) at the porta hepatis and 2.8 ± 1.2 mm (SD) at the widest point, the regression coefficient between both diameters being r = 0.84. None of the healthy subjects had a diameter larger than 7 mm at any site, and in 95% of all subjects the diameters were less than 4 mm at both sites of measurement. The diameters were significantly correlated with age (r = 0.16) and weight (r = 0.11), but not with sex, height, and body surface area. In 73 patients with cholelithiasis and in 55 patients after cholecystectomy, all of whom lacked clinical or laboratory signs of biliary obstruction, the average diameters at the porta hepatis were 3.8 ± 2.0 mm and 5.2 ± 2.3 mm, and at the widest point 4.8 ± 2.2 mm and 6.2 ± 2.5 mm, respectively. It is concluded that a common bile duct with any sonographic diameter larger than 4 mm should be followed closely and evaluated further with clinical examinations such as intravenous cholangiography unless cholecystectomy has been performed.     

No effect of conventional vs. minimally invasive surgical approach on clinical outcome and migration of a short stem total hip prosthesis at 2-year follow-up: A randomized controlled study

BackgroundShort stem hip prostheses have become a viable alternative for the treatment of hip osteoarthritis. In combination with minimally invasive surgery, short stem hip prostheses offer potential advantages of reduced surrounding tissue damage and faster rehabilitation. However, the limited perioperative visibility of these minimally invasive techniques may lead to reduced primary stability compared to conventional techniques. We hypothesized: a) increased migration of the minimally invasive group due to reduced primary stability and b) increased clinical scores of the minimally invasive group.MethodsSixty total hip arthroplasty patients were randomly assigned to undergo minimally invasive anterolateral modified Watson-Jones or conventional Hardinge surgery. All patients were treated with a Metha short stem prosthesis. Roentgen stereophotogrammetry and clinical scores were calculated after surgery and at 3, 6, 12, and 24 months postoperatively.FindingsNo statistically significant differences in implant migration and clinical scores were observed between the minimally invasive and conventional groups at any follow-up point. The largest average resultant migrations were 1.22 (SD 1.31) mm (conventional) and 1.18 (SD 1.18) mm (minimally invasive) after 24 months. The mean Harris Hip Score score improved from 54 (SD 10, conventional) and 52 (SD 13, minimally invasive) preoperatively to 97 (SD 5, both groups) after 24 months.InterpretationOverall, the differences in implant migration and clinical scores between the minimally invasive and conventional surgery groups were marginal and not clinically relevant. The data from this study suggest that good results can be expected from both the investigated approaches.     

Infrared Vein Imaging for Insertion of Peripheral Intravenous Catheter for Patients Requiring Isolation for Severe Acute Respiratory Syndrome Coronavirus 2 Infection: A Nonrandomized Clinical Trial

IntroductionEstablishing intravenous access is essential but may be difficult to achieve for patients requiring isolation for severe acute respiratory syndrome coronavirus 2 infection. This study aimed to investigate the effectiveness of an infrared vein visualizer on peripheral intravenous catheter therapy in patients with coronavirus disease 2019.MethodsA nonrandomized clinical trial was performed. In total, 122 patients with coronavirus disease 2019 who required peripheral intravenous cannulation were divided into 2 groups with 60 in the control group and 62 in the intervention group. A conventional venipuncture method was applied to the control group, whereas an infrared vein imaging device was applied in the intervention group. The first attempt success rate, total procedure time, and patients’ satisfaction score were compared between the 2 groups using chi-square, t test, and z test (also known as Mann-Whitney U test) statistics.ResultsThe first attempt success rate in the intervention group was significantly higher than that of control group (91.94% vs 76.67%, ?² = 5.41, P = .02). The procedure time was shorter in the intervention group (mean [SD], 211.44 [68.58] seconds vs 388.27 [88.97] seconds, t = 12.27, P < .001). Patients from the intervention group experienced a higher degree of satisfaction (7.5 vs 6, z = ?3.31, P < .001).DiscussionPeripheral intravenous catheter insertion assisted by an infrared vein visualizer could improve the first attempt success rate of venipuncture, shorten the procedure time, and increase patients’ satisfaction.     

Greater saphenous vein location in a pediatric population

The purpose of this study was to assess the accuracy of a landmark technique for cannulation of the greater saphenous vein (GSV) near the medial malleolus. We performed bedside ultrasound in a convenience sample of 100 children, ages 3 to 16 years, to evaluate the anatomy of the GSV at the ankle. Despite the proposed constancy of the landmark technique regardless of patient age, the GSV location varied significantly with increasing patient age and weight. In children less than 10 years old or weighing less than 40 kg, the traditional landmark rarely predicted the precise location of the GSV.     

Sonographic features of umbilical vein recanalization for a Rex shunt on cavernous transformation of portal vein in children

BACKGROUNDThe Rex shunt was widely used as the preferred surgical approach for cavernous transformation of the portal vein (CTPV) in children that creates a bypass between the superior mesenteric vein and the intrahepatic left portal vein (LPV). This procedure can relieve portal hypertension and restore physiological hepatopetal flow. However, the modified procedure is technically demanding because it is difficult to make an end-to-end anastomosis of a bypass to a hypoplastic LPV. Many studies reported using a recanalized umbilical vein as a conduit to resolve this problem. However, the feasibility of umbilical vein recanalization for a Rex shunt has not been fully investigated.AIMTo investigate the efficacy of a recanalized umbilical vein as a conduit for a Rex shunt on CTPV in children by ultrasonography.METHODSA total of 47 children who were diagnosed with CTPV with prehepatic portal hypertension in the Second Hospital, Cheeloo College of Medicine, Shandong University, were enrolled in this study. Fifteen children received a recanalized umbilical vein as a conduit for a Rex shunt surgery and were enrolled in group I. Thirty-two children received the classic Rex shunt surgery and were enrolled in group II. The sonographic features of the two groups related to intraoperative and postoperative variation in terms of bypass vessel and the LPV were compared.RESULTSThe patency rate of group I (60.0%, 9/15) was significantly lower than that of group II (87.5%, 28/32) 7 d after (on the 8^th d) operation (P < 0.05). After clinical anticoagulation treatment for 3 mo, there was no significant difference in the patency rate between group I (86.7%, 13/15) and group II (90.6%, 29/32) (P > 0.05). Moreover, 3 mo after (at the beginning of the 4^th mo) surgery, the inner diameter significantly widened and flow velocity notably increased for the bypass vessels and the sagittal part of the LPV compared to intraoperative values in both shunt groups (P < 0.05). However, there was no significant difference between the two surgical groups 3 mo after surgery (P > 0.05). CONCLUSIONFor children with hypoplastic LPV in the Rex recessus, using a recanalized umbilical vein as a conduit for a Rex shunt may be an effective procedure for CTPV treatment.     

Ultrafast time-resolved contrast-enhanced 3D pulmonary venous cardiovascular magnetic resonance angiography using SENSE combined with CENTRA-keyhole.

PURPOSE: To evaluate the diagnostic benefit of time-resolved CENTRA-keyhole contrast-enhanced cardiovascular magnetic resonance angiography (CE-CMRA) for improving arterial-venous separation of pulmonary vessels. METHODS: Twenty-three patients (18 males; age = 58 +/- 11y) after radiofrequency pulmonary vein isolation to treat atrial fibrillation were examined using CENTRA-keyhole based multi-phase 3D CE-CMRA yielding 6 near-isotropic 3D datasets every 1.6 s (50-60 coronal partitions, 1.4 x 1.4 x 1.3 mm, SENSE-factor 3). Results were compared with conventional non-keyhole CE-CMRA (identical parameters, SENSE-factor 2). RESULTS: Data acquisition was accelerated by a speedup factor of approximately 9 compared with the reference CE-CMRA (SENSE 1.5*, keyhole 6*). No pulmonary venous stenoses were detected by either method, overall pulmonary venous diameters were 17.1 +/- 3.6 mm. Applying Bland-Altman analysis, vessel diameters differed by a mean of 0.1 mm + 2.1 mm/-2.0 mm (mean +/- 2 SD), indicating close agreement between both techniques. Interobserver variability was higher for CENTRA-keyhole (mean = 0.1 mm; mean +/- 2 SD: +2.5 mm/-2.3 mm) compared to conventional technique (0.0 mm; +1.6 mm/-1.5 mm), corresponding to a percentual deviation (mean +/- 2 SD) of the mean diameter of approximately +/- 15% (keyhole CE-CMRA) and +/- 10% (conventional CE-CMRA), respectively. Using keyhole-based time-resolved CE-CMRA, the contrast between pulmonary veins versus aorta/pulmonary artery was significantly increased (p < 0.05), which improved vessel depiction. In 12 cases, the contrast bolus arrival was delayed in one of the pulmonary veins by 1 dynamic frame (= 1.6 seconds); in 7 cases by 2 frames (= 3.2 seconds) and in 1 subject by 3 frames (= 4.8 seconds). The bolus usually appeared first in the upper right pulmonary vein whereas a delay occurred most often in the lower left pulmonary vein. CONCLUSIONS: Conventional CE-CMRA may be advantageous for accurate vessel size measures as evidenced by superior interobserver reproducibility in this study. Multi-dynamic CE-CMRA using CENTRA-keyhole with SENSE, however, allows for improved arterio-venous separation of pulmonary vessels and additional dynamical information on pulmonary venous perfusion, while maintaining high spatial resolution. Exact bolus timing is no longer needed.     

Dilatation of the pulmonary veins in atrial fibrillation: a transesophageal echocardiographic evaluation

Ectopic beats originating from sleeves of atrial tissue within the pulmonary veins (PVs) can induce and sustain paroxysmal atrial fibrillation (AF). Left atrial stretch and dilatation favors the development of atrial ectopy and AF. Similarly, PV dilatation, if present, might trigger PV ectopy in patients with AF. This study was designed to evaluate whether PV dilatation is present in patients with nonfocal AF and whether the PV diameter correlates to the left atrial diameter (LAD). The diameters of the right superior (RSPV) and left superior PV (LSPV) were measured at the ostium and at a depth of 1 cm in 170 patients (AF, n = 75; sinus rhythm [SR], n = 95) using transesophageal echocardiography. The LAD was determined by transthoracic echocardiography. The diameters of the PVs were significantly larger in patients with AF than in patients with SR (LSPV(ostium): AF 13.6 +/- 3.5 mm vs SR 10.6 +/- 2.7 mm, P < 0.001; LSVP(1cm): AF 12.5 +/- 2.9 mm vs SR 10.2 +/- 2.5 mm, P < 0.001; RSPV(ostium): AF 13.9 +/- 3.5 mm vs SR 11.7 +/- 2.9 mm, P < 0.001; RSVP(1cm): AF 12.8 +/- 2.8 mm vs SR 10.6 +/- 2.6 mm, P < 0.05). Similarly, LAD was larger in patients with AF (44.7 +/- 7.7 mm) as compared to patients with SR (38.8 +/- 6.8 mm, P < 0.001). Neither for the SR nor the AF group did the PV size correlate to the LAD. AF is associated with a significant enlargement of the RSPV, LSPV, and LAD. There is no correlation between LAD and PV diameters. This raises the question whether PV dilatation in patients with AF is a cause or a consequence of AF and whether it may contribute to the development and perpetuation of AF.