肺栓塞诊断中SPECT/CT融合显像技术与肺通气/灌注平面显像方法的比较

目的:探讨SPECT/CT融合显像技术在诊断肺动脉栓塞(pulmonary embolism,PE)中的价值?方法:45例PE疑似患者分别行常规肺通气/灌注(V/P)平面显像及SPECT/CT断层融合显像,比较两种检测方法诊断PE的敏感性?特异性?准确性的差异?结果:常规肺V/P显像的敏感性?特异性?准确性分别为78.6%?58.8%和71.1%,SPECT/CT断层融合显像的敏感性?特异性?准确性分别为92.9%?88.2%和91.1%,两种影像学检查在定性诊断PE方面有统计学差异(χ2=14.63,P < 0.05)?结论:SPECT/CT肺断层融合显像法优于常规肺V/P显像,可作为诊断PE的一种新的常规检测方法?     

V/Q显像与SPECT-CT断层显像在慢性血栓栓塞性肺动脉高压中的研究

目的对比肺通气/灌注平面显像与肺灌注SPECT-CT同机融合断层显像在慢性血栓栓塞性肺动脉高压肺段动脉及亚段动脉栓子的检出效能。方法选取经临床Wells评分、临床资料、实验室检查及X线肺动脉造影综合确诊为慢性血栓栓塞性肺动脉高压的35例患者,其中男25例,女10例,平均年龄（52.4±16.5）岁,合并近期手术者3例、心力衰竭者7例、既往存在急性肺栓塞10例、合并下肢深静脉血栓21例;临床Wells评分,高度可能性者15例,中度可能性者20例。所有患者均接受肺通气/灌注平面显像、肺灌注SPECT-CT断层同机融合显像及X线肺动脉造影检查,检查于5 d内完成并由核医学科及放射科有经验医师进行独立、双盲法阅片。采用SPSS19.0统计软件对肺通气/灌注平面显像、SPECT-CT同机融合显像及X线肺动脉造影段及亚段的检查结果进行χ2检验及Kappa一致性检验。结果对于肺段动脉栓子,肺通气/灌注平面显像与肺灌注SPECT-CT的敏感度、特异度、准确度分别为89.63%、69.41%、77.14%;92.53%、93.57%、93.17%。亚段肺动脉栓子,肺通气/灌注平面显像与肺灌注SPECT-CT敏感度、特异度、准确度分别为60.97%、89.05%、82.14%;63.87%、94.0%、86.59%。结论肺灌注SPECT-CT在保留了肺通气/灌注平面显像对肺段及亚段病变定位较高的敏感性同时,提高了对肺段及亚段病变定位的特异性。     

肺通气/血流灌注显像与螺旋CT肺动脉造影诊断肺栓塞的实验研究

目的评价肺通气/血流灌注(pulmonary perfusion/ventilation,V/Q)显像与64层螺旋CT肺动脉造影(spiral computed tomographic pulmonary angiography,SCTPA)诊断肺栓塞的灵敏度和特异性。方法12只家兔按不同时间点分成4个实验组,每组3只,另设2只作为对照组。实验组经颈静脉插管注入海绵栓子制备急性肺栓塞模型,建模后分组行V/Q显像和SCTPA检查,随后处死实验动物行病理解剖,查找并记录肺动脉栓子位置及数目。对照组颈静脉插管注入生理盐水,于24 h和第3天处死。结果实验组家兔术中死亡1只,11只建模成功。家兔处死后共解剖动脉165支,发现栓子43个,栓塞肺动脉39支。V/Q显像共检出36处节段肺动脉栓塞,与病理解剖对照,假阳性7处、假阴性10处;SCTPA共诊断栓塞肺动脉32支,假阳性6支、假阴性13支。V/Q显像、SCTPA诊断实验家兔肺栓塞的灵敏度分别为74.4%、66.7%,特异性分别为94.4%和95.2%,准确性分别为89.7%和88.5%。结论肺通气/血流灌注显像诊断肺栓塞的灵敏度和准确性高于64层螺旋CT肺动脉造影,...     

简易肺通气导入器在同日法肺通气/灌注显像中的应用

目的探讨简易快速一次性使用肺通气导入器在同日法肺通气/灌注显像诊断肺栓塞(PE)中的临床价值。方法对疑诊PE的132例患者,采用美国ADAC VERTEX双探头SPECT行八个体位肺通气/灌注平面显像。肺通气显像使用一次性使用肺通气导入器雾化99Tcm-DTPA1110MBq,采集计数为1×105,时间为7min;随即保持患者体位不变,静脉缓慢注入99Tcm-MAA296MBq,行相应八体位肺灌注显像,计数率约为6×103/s,采集计数为5×105,时间为6min。结果以临床PIOPED诊断标准为依据,132例患者中,60例确诊为PE,48例排除PE,共108例明确诊断;另有24例(18.2%)为非确定性诊断,经其他影像检查和临床诊断出10例为PE和14例排除PE;同时,采用免疫比浊法测定患者血浆D-二聚体。同日法肺通气/灌注显像诊断PE的灵敏度、特异性、准确性、阳性预测值和阴性预测值分别为85.7%,77.4%,81.8%,81.1%和82.8%;血浆D-二聚体诊断分别为97.4%,44.6%,75.0%,70.5%和92.6%。结论简易快速同日法肺通气/灌注显像对PE诊断具有较高的临床价值。     

11例核素肺通气/肺灌注显像诊断肺栓塞的观察和护理

目的 :为了提高肺通气 /肺灌注 (V/ Q)显像对肺栓塞诊断的准确性 ,探讨影响 (V/ Q)显像质量的因素 ,给予护理干预。方法 :通过对 11例可疑肺动脉栓塞 (PE)病人行 (V/ Q)显像 ,对其中 1例同时进行 99m Tc-大颗粒聚合白蛋白 (MAA)下肢静脉和肺灌注显像进行的观察 ,有针对性地实施护理措施。结果 :11例可疑 PE病人中 ,有 9例 (V/ Q)显像图像质量清晰 ,有 2例 (V/ Q)显像中的肺通气不成功。结论 :肺通气显像的成败取决于患者吸气的方法 ,应从加强病人在检查前作有效的腹式呼吸训练着手 ,有针对性地实施护理措施 ,是提高 (V/ Q)显像成功与否的关键     

肺灌注断层显像和平面显像对肺栓塞诊断的价值研究

目的：评价肺灌注断层显像对肺栓塞（PE）的诊断价值。方法：对76例确诊为PE的患者进行肺灌注断层和平面显像,次日行肺通气显像,显像结果和CT肺动脉造影（CTPA）进行对比分析。结果：在76例PE患者中,肺灌注断层显像阳性72例,检出率为94．7％;肺灌注平面显像阳性64例,检出率为84．2％,两种方法PE检出率差异有统计学意义（P〈．05）。76例患者中,CTPA显示受累肺段为329个,肺灌注断层显像示314个肺段阳性,肺灌注断层显像与CTPA的符合率为95．4％;肺灌注平面显像示261个肺段阳性,两者符合率为79．3％,两符合率比较,差异有高度统计学意义（P〈0．01）。结论：肺灌注断层显像能显著提高对PE的诊断率,可作为诊断PE的常规筛查方法。     

螺旋CT与核素肺通气/灌注显像对肺动脉栓塞的诊断价值

目的 评价螺旋CT肺动脉造影(CTPA)与核素肺通气/灌注(V/Q)显像在诊断肺动脉栓塞中的价值.方法 临床疑似肺栓塞(PE)的患者84例,均完成CTPA和V/Q显像,所有检查均在3-5 d内完成,依照最终临床诊断评价两种方法诊断PE的临床价值.结果 CTPA正确诊断PE 35例,假阳性2例,假阴性5例,诊断PE的灵敏度、特异性、准确性、阴性预测值、阳性预测值分别为:87.50%,95.45%,91.67%,89.36%,94.59%;肺V/Q显像正确诊断PE 33例,假阳性3例,假阴性7例,诊断PE的灵敏度、特异性、准确性、阴性预测值、阳性预测值分别为:82.50%,93.18%,88.10%,85.41%,91.67%.结论 CTPA在灵敏度、特异性及准确性诊断比率方面均较V/Q显像的价值高,可作为临床疑诊肺栓塞病例的有效检查方法.     

核医学肺通气/灌注显像对诊断肺栓塞的应用探讨

目的:探讨同日法肺通气/灌注(V/P)显像在肺栓塞(PE)诊断中的临床价值。方法:临床疑诊PE患者184例,男110例,女74例,平均年龄42.42岁。行同日法肺V显像及肺P联合显像,同时行血浆D-二聚体测定。以临床PIOPED诊断标准为依据,来评价同日法肺V/P显像对PE的诊断价值。结果:184例患者中,同日法肺V/P显像诊断PE的灵敏度、特异性和准确性分别为88.89%、80.85%和84.78%;送检科室中呼吸内科、心血管内科最多,分别为40.76%和33.70%;其中确诊为PE患者的科室急诊科和外科最多,分别为100%和61.54%,呼吸内科和心血管内科其次,为54.67%和38.71%。结论:同日法肺V/P显像快捷、简便、安全,无创,对PE诊断具有较高的临床价值。     

SPECT/CT肺灌注显像与肺通气/灌注平面显像在肺栓塞诊断中的应用比较

目的分析单光子发射型计算机断层/低剂量平扫CT(SPECT/CT)肺灌注显像与肺通气/灌注(V/Q)平面显像在肺栓塞诊断中的应用。方法将2017年6月至2018年10月我院收治的120例疑似肺栓塞患者作为研究对象,所有患者均进行SPECT/CT肺灌注显像和V/Q平面显像检查,以临床最终诊断结果为准,评估SPECT/CT肺灌注显像和V/Q平面显像对肺栓塞的诊断效能。结果 120例患者中最终有100例诊断为肺栓塞,其中肺段病变247个,亚肺段病变285个。SPECT/CT肺灌注显像对肺栓塞诊断灵敏度、特异度、准确度、阳性预测值、阴性预测值分别为89.00%、90.00%、89.17%、97.80%、62.07%,均大于V/Q平面显像的81.00%、80.00%、80.83%、95.29%、45.71%。SPECT/CT肺灌注显像对肺栓塞肺段病变检出率87.04%与V/Q平面显像的82.19%无显著差异(P>0.05),对亚肺段病变检出率92.28%高于V/Q平面显像的85.96%(P<0.05)。结论 SPECT/CT肺灌注显像对肺栓塞的诊断效能优于V/Q平面显像,且可提高对亚肺段病变检出率。     

肺灌注和肺通气显像诊断肺栓塞的临床应用价值

目的:评价肺灌注/通气显像(V/Q)诊断肺栓塞的临床应用价值。方法:临床疑有肺栓塞(PE)的患者60例,男女各30例,平均年龄(43.5±11.3)岁。均行肺V/Q显像及肺动脉造影(CPA)。结果:60例患者中44例肺V/Q显像示肺叶、肺段或多发亚肺段不相匹配的放射性分布稀疏或缺损,提示PE;经肺动脉造影诊断42例为PE,2例排除PE。16例患者的肺V/Q显像肺叶、肺段或多发亚肺段相匹配稀疏或缺损,提示排除PE;肺动脉造影诊断1例为PE,15例排除PE。肺V/Q显像诊断PE的灵敏度为97.7%(42/43例),特异性为83.3%(15/17例)。结论:肺V/Q显像诊断PE是目前临床诊断肺栓塞的最有价值的无创性诊断方法之一,具有安全、无创、简便、经济等优点。     

V/Q显像与CT肺动脉造影在慢性血栓栓塞性肺动脉高压不同栓塞水平中的研究

目的对比肺通气/灌注显像(ventilation/perfusion scan,V/Q)与CT肺动脉造影(CT pulmonary angiography,CTPA)在慢性血栓栓塞性肺动脉高压(chronic thromboembolic pulmonary hypertension,CTEPH)肺段动脉及亚段动脉栓子的检出效能。方法选取经临床Wells评分、临床资料、实验室检查及X线肺动脉造影综合确诊为慢性血栓栓塞性肺动脉高压的39例患者,其中男28例,女11例,平均年龄(51.0±16.1)岁,合并近期手术者4例、心力衰竭者7例、既往存在急性肺栓塞12例、合并下肢深静脉血栓26例。临床Wells评分,高度可能性者17例,中度可能性者22例。所有患者均接受V/Q单光子发射计算机断层成像术(single photon emission CT,SPECT)断层显像、CTPA及X线肺动脉造影(pulmonary artery angiography,PAG)检查,检查于3～7 d内完成并由放射科及核医学科有经验医师进行独立、双盲法阅片。采用SPSS 13.0统计软件对V/Q SPECT及CTPA与PAG段及亚段的检查结果进行χ2检验及Kappa一致性检验。结果对于肺段动脉栓子,V/Q SPECT与CTPA的敏感度、特异度、准确度分别为84.7%、77.7%,94.6%、98.2%,90.9%、91.2%;亚段肺动脉栓子,V/Q SPECT与CTPA敏感度、特异度、准确度分别为63.2%、50.4%,94.8%、94.8%,93.8%、83.9%。结论 V/Q显像对段及亚段病变定位的敏感性较高,临床中V/Q显像正常即可排除CTEPH,若存在异常须进一步行CTPA、PAG及磁共振成像(magnetic resonance imaging,MRI)等检查进一步明确。     

肺灌注断层显像与平面显像在肺栓塞诊断中的比较

目的判定肺灌注断层显像(SPECT肺灌注显像)对肺血栓栓塞症(PE)的诊断价值。方法对227例明确诊断为PE的患者在进行肺平面通气显像的同时,进行了SPECT肺灌注显像和肺平面灌注显像,并与CT肺动脉造影(CTPA)结果进行对比分析。结果在227例PE患者中,平面肺灌注显像阳性者203例,检出率为89.4%。SPECT肺灌注显像阳性者223例,检出率为98.2%。平面肺灌注显像与SPECT肺灌注显像对PE的检出率差异有统计学意义(P<0.01)。在221例有CTPA诊断结果的患者中,CTPA显示受累肺段为976个,平面肺灌注显像显示796个肺段阳性,两者符合率为81.6%;SPECT肺灌注显像显示937个肺段阳性,SPECT肺灌注显像与CTPA的符合率为96%;两符合率之间差异有统计学意义(P<0.01)。结论SPECT肺灌注显像能明显提高对PE的诊断价值,可取代肺平面灌注显像,成为诊断PE的常规检查方法。     

双能CT肺灌注成像评价肺栓塞栓子形态与功能改变的相关性研究

采用双源计算机体层摄影（DSCT）双能量肺灌注成像诊断肺动脉栓塞（PE）,探讨栓塞部位及形态与双能量肺灌注的相关性。方法收集临床怀疑PE,行DSCT 双能量肺灌注成像患者120 例。①分析PE部位及分型;②分析PE 部位及分型与双能量肺灌注灌注缺损类型的比较;③分析纵隔窗肺动脉增强图像与肺灌注图像诊断PE的吻合性,以及肺灌注图像与肺窗图像诊断PE 肺内灌注改变的吻合性。结果①从PE 发生部位分析,右侧PE 的比例高于左侧肺动脉,肺叶动脉较左、右肺动脉干多,双下肺动脉较双上肺动脉多;从形态上分析,以中心型和完全闭塞型居多,附壁型次之,不规则型及马鞍型较少;②在不同类型的肺动脉干PE中,完全型易发生于全肺或肺叶灌注缺损,附壁型或中心型常出现肺叶或段灌注缺损;若PE 发生在肺叶或肺段,则完全型多出现肺叶或段灌注缺损,而附壁型或中心型多出现肺段或亚段灌注缺损或无灌注缺损;若PE发生在亚段,则多见亚段灌注缺损或无灌注缺损;③纵隔窗肺动脉增强图像与肺灌注图像诊断PE 的吻合性好,肺灌注图像与肺窗图像诊断PE肺内灌注改变的吻合性差。结论肺灌注成像与PE 部位及形态具有一定的相关性,DSCT 双能量肺灌注成像能协助诊断PE。     

A preliminary study of imaging paclitaxel-induced tumor apoptosis with 99Tcm-His10-Annexin V

Backgroud In tumors the process of apoptosis occurs over an interval of time after chemotherapy. It is important to determine the best time for detecting apoptosis by in vivo imaging. In this study, we evaluated the dynamics and feasibility of imaging non-small cell lung cancer (NSCLC) apoptosis induced by paclitaxel treatment using a 99Tcm-labeled Annexin V recombinant with ten consecutive histidines (His10-Annexin V) in a mouse model.

Methods 99Tcm-His10-Annexin V was prepared by one step direct labeling; radio-chemical purity (RCP) and radio-stability was tested. The binding of 99Tcm-His10-Annexin V to apoptotic cells was validated in vitro using camptothecin-induced Jurkat cells. In vivo bio-distribution was determined in mice by dissection. The human H460 NSCLC tumor cell line (H460) tumor-bearing mice were treated with intravenous paclitaxel 24, 48 and 72 hours later. 99Tcm-His10-Annexin V was injected intravenously, and planar images were acquired at 2, 4 and 6 hours post-injection on a dual-head gamma camera fitted with a pinhole collimator. Tumor-to-normal tissue ratios (T/NT) were calculated by ROI analysis and they reflected specific binding of 99Tcm-His10-Annexin V. Mice were sacrificed after imaging. Caspase-3, as the apoptosis detector, was determined by flow cytometry, and DNA fragmentation was analyzed by the terminal deoxynucleotidytransferase mediated dUTP nick-end labeling (TUNEL) assay. Nonspecific accumulation of protein was estimated using bovine serum albumin (BSA). The imaging data were correlated with TUNEL-positive nuclei and caspase-3 activity.

Results 99Tcm-His10-Annexin V had a RCP >98% and high stability 2 hours after radio-labeling, and it could bind to apoptotic cells with high affinity. Bio-distribution of 99Tcm-His10-Annexin V showed predominant uptake in kidney, relatively low uptake in myocardium, liver and gastrointestinal tract, and rapid clearance from blood and kidney was observed. The T/NT was significantly increased after paclitaxel treatment, whereas it was low in untreated tumors (T/NT=1.43±0.18). The %ID/g activity in Group 2 (24 hours), Group 3 (48 hours) and Group 4 (72 hours) after treatment was 2.55±0.73, 3.35±1.10, and 3.4±0.96, respectively. Whereas in the non-treated group, Group 1, %ID/g was 1.10±0.18. The radiotracer uptake was positively correlated to the apoptotic index (r=0.852, P<0.01), as well as caspase-3 activity (r=0.816, P<0.01).

Conclusion This study addresses the dynamics and feasibility of imaging non-small cell lung tumor apoptosis using 99Tcm-His10-Annexin V.

     

Exercise Echocardiography or Exercise SPECT Imaging?: A Meta-analysis of Diagnostic Test Performance

Context.— Cardiac imaging has advanced rapidly, providing clinicians with several choices for evaluating patients with suspected coronary artery disease, but few studies compare modalities directly. Objectives.— To review the contemporary literature and to compare the diagnostic performance of exercise echocardiography (ECHO) and exercise single-photon emission computed tomography (SPECT) imaging in the diagnosis of coronary artery disease. Data Sources.— Studies published between January 1990 and October 1997 identified from MEDLINE search; bibliographies of reviews and original articles; and suggestions from experts in each area. Study Selection.— Articles were included if they discussed exercise ECHO and/or exercise SPECT imaging with thallous chloride TI 201 (thallium) or technetium Tc 99m sestamibi for detection and/or evaluation of coronary artery disease, if data on coronary angiography were presented as the reference test, and if the absolute numbers of true-positive, false-negative, true-negative, and false-positive observations were available or derivable from the data presented. Studies performed exclusively in patients after myocardial infarction, after percutaneous transluminal coronary angioplasty, after coronary artery bypass grafting, or with recent unstable coronary syndromes were excluded. Data Extraction.— Clinical variables, technical factors, and test performance were independently extracted by 2 reviewers on a standardized spreadsheet. Discrepancies were resolved by consensus. Results.— Forty-four articles met inclusion criteria. In pooled data weighted by the sample size of each study, exercise ECHO had a sensitivity of 85% (95% confidence interval [CI], 83%-87%) with a specificity of 77% (95% CI, 74%-80%). Exercise SPECT yielded a similar sensitivity of 87% (95% CI, 86%-88%) but a lower specificity of 64% (95% CI, 60%-68%). In a summary receiver operating characteristic model comparing exercise ECHO performance to exercise SPECT, exercise ECHO was associated with significantly better discriminatory power (parameter estimate, 1.18; 95% CI, 0.71-1.65), when adjusted for age, publication year, and a setting including known coronary artery disease for SPECT studies. In models comparing the discriminatory abilities of exercise ECHO and exercise SPECT vs exercise testing without imaging, both ECHO and SPECT performed significantly better than exercise testing. The incremental improvement in performance was greater for ECHO (3.43; 95% CI, 2.74-4.11) than for SPECT (1.49; 95% CI, 0.91-2.08). Conclusions.— Exercise ECHO and exercise SPECT have similar sensitivities for the detection of coronary artery disease, but exercise ECHO has better specificity and, therefore, higher overall discriminatory capabilities as used in contemporary practice.      

肺通气/灌注与CT肺动脉造影诊断肺栓塞对比分析

目的:探讨肺通气/灌注(V/Q)显像与CT肺动脉造影(CTPA)在肺栓塞诊断中的应用价值。方法:选择我院2006年4月～2010年4月收治的肺栓塞患者164例,按照疾病程度分为大面积肺栓塞组(48例)、次大面积肺栓塞组(56例)和非大面积肺栓塞组(60例)3组,对3组患者V/Q显像与CTPA检出率进行比较。结果:肺V/Q显像总检出率为91.46%,CTPA总检出率为90.24%,2种方法总检出率差异无统计学意义(P>0.05)。不同方法对A、B、C组阳性检出率不同,A组CTPA检出率明显高于肺V/Q显像,B、C组V/Q显像检出率明显高于CTPA,差异均有统计学意义(t分别为5.83、5.02、5.13,P均<0.05)。结论:肺V/Q显像与CTPA诊断栓塞各有优缺点,临床中根据患者情况结合应用,为治疗提供准确有效的信息。     

肺栓塞:多层螺旋CT诊断与随访

目的评价多层螺旋CT在PE诊断及随访中的价值。方法81例临床怀疑PE患者采用四排探测器多层螺旋CT行CTPA,其中26例患者行联合CT静脉造影(CT venography,CTV)。对治疗患者行CT随访观察,阴性患者3个月后电话随访。结果81例患者共进行172次CTPA,25例患者检出P(E30.9%)。11例患者检出深静脉血栓(deep vein thrombolism,DVT),其中10例患者合并PE。16例大面积肺栓塞患者行溶栓及抗凝治疗,其余患者9例PE患者行抗凝治疗。随访CT证实溶栓后24h,11例PE缩小,5例消失。2周和1个月复查,除1例慢性PE保持不变,5例患者见段及亚段小栓子外,其余患者栓子消失。90d复查CT,仅有1例患者PE复发。DVT于6例患者中消失,4例缩小。CTPA阴性患者3个月后电话随访无PE临床征象。结论多层螺旋CT可以作为肺栓塞诊断与随访的有效的影像学检查方法。     

Risk of Fatal Pulmonary Embolism in Patients With Treated Venous Thromboembolism

Context.— The most serious complication of deep vein thrombosis (DVT) or nonfatal pulmonary embolism (PE) is fatal PE. However, reliable estimates as to the risk of fatal PE in patients with treated DVT or PE are lacking. Objective.— To provide reliable estimates of the risk of fatal PE and the case-fatality rate of recurrent DVT or PE among patients presenting with symptomatic DVT or PE, during and following 3 months of anticoagulant therapy. Data Sources.— A MEDLINE literature search was performed to identify prospective studies in which patients with symptomatic DVT or PE were treated with 5 to 10 days of heparin and 3 months of oral anticoagulants. We searched the years 1966 to September 1997 using the search terms thrombophlebitis, diagnosis, drug therapy, and prognosis. Current Contents and bibliographies were also scanned. Data Extraction.— Of 137 retrieved studies, 25 studies satisfied predetermined methodologic criteria and were included in the analysis. Data Synthesis.— Among patients presenting with DVT, the rate of fatal PE during anticoagulant therapy was 0.4% (95% confidence interval [CI], 0.2%-0.6%); following anticoagulant therapy it was 0.3 per 100 patient-years (95% CI, 0.1-0.8). The case-fatality rate of recurrent DVT or PE during anticoagulant therapy was 8.8% (95% CI, 5.0%-14.1%); following anticoagulant therapy it was 5.1% (95% CI, 1.4%-12.5%). Among patients presenting with PE, the rate of fatal PE during anticoagulant therapy was 1.5% (95% CI, 0.9%-2.2%); following anticoagulant therapy it was 0 per 265 patient-years (95% CI, 0-3.6). The case-fatality rate of recurrent DVT or PE among patients presenting with PE was 26.4% (95% CI, 16.7%-38.1%). Conclusion.— Among patients with symptomatic PE or DVT who are treated with anticoagulants for 3 months, fatal PE is rare during and following anticoagulant therapy. Patients presenting with PE are more likely to die of recurrent PE or DVT than are patients presenting with DVT.