Outcomes from a tertiary care center using a catheter thrombectomy system for managing acute iliofemoral deep vein thrombosis.

OBJECTIVE: The aim of the present study was to report a large, single-center experience using the ClotTriever thrombectomy system (Inari Medical, Irvine, CA) for the management of acute iliofemoral (IF) deep vein thrombosis (DVT). One limitation of all endovascular devices for the treatment of acute IF-DVT has been the inability to completely remove all acute thrombus and the need for adjunctive thrombolysis with its attendant risk of bleeding complications. METHODS: A single-center retrospective review of consecutive patients with acute IF-DVT treated with the ClotTriever thrombectomy system (Inari Medical) is reported. Procedural efficacy was evaluated by an independent core imaging laboratory (Syntactx, New York, NY). Both procedural and in-hospital safety were assessed during the index hospitalization. The treated vein patency was assessed using duplex ultrasound at 30 days after the procedure. RESULTS: A total of 96 patients were included in the present retrospective review, 40 of whom (40%) had contraindications to thrombolytic therapy. In terms of efficacy, 93 patients (97%) had ≥75% thrombus removal. During the index hospitalization, two patients (2%) had experienced a symptomatic pulmonary embolus. However, no mortality, major bleeding, or device-related complications had occurred in the study population. Of the 96 patients, 64 had undergone duplex ultrasound at 30 days after the procedure. Of the 64 patients, 62 had normal flow (97%), 53 (83%) had normal compressibility, and 11 (17%) had partial compressibility. CONCLUSIONS: The ClotTriever thrombectomy catheter was both safe and effective in our cohort of patients with acute IF-DVT outside a randomized clinical trial.

Detection of maternal X chromosome abnormalities using single nucleotide polymorphism-based noninvasive prenatal testing.

BACKGROUND: Maternal X chromosome abnormalities may cause discordant results between noninvasive prenatal screening tests and diagnostic evaluation of the fetus/newborn, leading to unnecessary invasive testing. Women with X chromosome abnormalities are at increased risk for reproductive, pregnancy, or other health complications, which may be reduced or ameliorated by early diagnosis, monitoring, and intervention. OBJECTIVE: This study aimed to validate a single nucleotide polymorphism-based noninvasive prenatal test to identify X chromosome abnormalities of maternal origin. STUDY DESIGN: All tests unable to evaluate fetal risk for aneuploidy because of uninformative algorithm results were eligible for inclusion. Two groups of cases were prospectively identified: Group A (n=106) where a maternal X chromosome abnormality was suspected and Group B (control group, n=107) where a fetal chromosome abnormality involving chromosome 13, 18, 21, or X was suspected but did not meet criteria for reporting. Maternal DNA was isolated from the plasma-depleted cellular pellet and sent to a reference laboratory for blinded analysis using chromosomal microarray. A chromosome abnormality involving chromosomes 13, 18, 21, or X was reported by the reference laboratory if ≥5 Mb in size and present in ≥20% of the DNA. RESULTS: A maternal X chromosome abnormality was suspected in 1/1305 tests (149/194,385; 0.08%). In Group A, a maternal X chromosome abnormality was confirmed in 100/106 cases (94.3% positive predictive value, 1-sided 97.5% confidence interval, 88.1%-100.0%). Turner syndrome was the most commonly suspected maternal abnormality (58/106, 54.7%), with confirmation of mosaic or nonmosaic 45,X by microarray in 38/58 (65.5%) cases. Noninvasive prenatal screening tests suspected the presence of maternal 47,XXX with or without mosaicism in 40/106 (37.7%) cases, confirmed by microarray in 38/40 (95.0%). In Group B (n=107), no maternal microarray abnormalities were reported, providing a negative predictive value of 100% (1-sided 97.5% confidence interval, 96.6%-100.0%). CONCLUSION: When noninvasive prenatal testing suspected a maternal X chromosome abnormality, maternal microarray confirmed an X chromosome abnormality with 94.3% positive predictive value. Of the maternal X chromosome abnormalities detected by array, >50% were 45,X. When fetal chromosome abnormalities involving chromosomes 13, 18, 21, or X were suspected, no maternal chromosome abnormalities were reported, yielding a negative predictive value of 100%. Women with maternal X abnormalities suspected with noninvasive prenatal testing may be at increased risk for reproductive and health complications; early evaluation and treatment may prevent long-term consequences or disability.

The clinical characteristics of lower extremity lymphedema in 440 patients.

BACKGROUND: Lower extremity lymphedema is frequently encountered in the vascular clinic. Established dogma purports that cancer is the most common cause of lower extremity lymphedema in Western countries, whereas chronic venous insufficiency (CVI) is often overlooked as a potential cause. Moreover, lymphedema is typically ascribed to a single cause, yet multiple causes can coexist. METHODS: A 3-year retrospective analysis was conducted of demographic and clinical characteristics of 440 eligible patients with lower extremity lymphedema who presented for lymphatic physiotherapy to a university medical center's cancer-based physical therapy department. RESULTS: The four most common causes of lower extremity lymphedema were CVI (phlebolymphedema; 41.8%), cancer-related lymphedema (33.9%), primary lymphedema (12.5%), and lipedema with secondary lymphedema (11.8%). The collective cohort was more likely to be female (71.1%; P < .0001), to be white (78.9%; P < .0001), to demonstrate bilateral distribution (74.5%; P < .0001), and to have involvement of the left leg (bilateral, 69.1% [P < .0001]; unilateral, 58.9% [P = .0588]). Morbid obesity was pervasive (mean weight and body mass index, 115.8 kg and 40.2 kg/m2, respectively) and significantly correlated with a higher International Society of Lymphology lymphedema stage (stage III mean weight and body mass index, 169.2 kg and 57.3 kg/m2, respectively, vs stage II, 107.8 kg and 37.5 kg/m2, respectively; P < .0001). Approximately one in three (35.7%) of the population sustained one or more episodes of cellulitis, but patients with stage III lymphedema had roughly twice the rate of soft tissue infection as patients with stage II, 61.7% vs 31.8%, respectively (P < .001). Multifactorial lymphedema was present in 25%. Approximately half of the patients with lipedema with secondary lymphedema (48.1%) or primary lymphedema (45.5%) had a superimposed cause of swelling that was usually CVI. Total knee arthroplasty was the most common cause of noncancer surgery-mediated worsening of pre-existing lymphedema. CONCLUSIONS: In a large cohort of patients treated in a cancer-affiliated physical therapy department, CVI (phlebolymphedema), not cancer, was the predominant cause of lower extremity lymphedema. One in four patients had more than one cause of lymphedema. Notable clinical characteristics included a proclivity for female patients, bilateral distribution, left limb, cellulitis, and nearly universal morbid obesity.

Combining the use of a fetal fraction-based risk algorithm and probability of an informative redraw in noninvasive prenatal testing for fetal aneuploidy.

Some women undergoing noninvasive prenatal testing (NIPT) do not receive an informative result due to low fetal fraction (FF). A proportion of these are at increased risk for fetal trisomy 13, 18, or triploidy, while others have no change from their prior risk. Women with an initial uninformative NIPT need to be counseled about any such change in their risk for fetal abnormality and also the probability that a redraw will be informative. To help in the decision making, we reviewed a dataset of single nucleotide polymorphism-based NIPT with uninformative results where a redraw was received. Risk for trisomy 13, 18, or triploidy was evaluated using a fetal fraction-based risk (FFBR) algorithm. Risk-unchanged women were further analyzed using a regression model to determine the likelihood of an informative redraw. Of 2,644 women with an uninformative NIPT and a redraw, 1,147 (43.4%) were high risk for trisomy 13, 18, or triploidy. 1,497 (56.6%) were risk unchanged and, of these, 975 (65.1%) cases had an informative redraw (i.e., risks were available for 2,122 (80%) of those initially classified as uninformative). The regression model for the risk-unchanged cases provided a new table for predicting an informative redraw. Likelihood of a successful redraw was significantly (p < .001) dependent on the initial FF, maternal weight, and time between blood draws. We conclude that the FFBR algorithm and the predictive model for an informative redraw provide complementary additions in the management of women presented with an initially uninformative SNP-based NIPT due to low FF. We suggest approaches for the counseling and follow-up testing for women with an initially uninformative NIPT.

Factors Associated With Informative Redraw After an Initial No Result in Noninvasive Prenatal Testing.

OBJECTIVE: Noninvasive prenatal testing (NIPT) sometimes fails to provide a test result, usually as a result of low cell-free DNA fetal fraction. We investigated how initial fetal fraction, maternal weight, gestational age, and time between blood sampling contribute to obtaining an informative result when a redraw is performed. METHODS: We performed a retrospective data review of NIPT samples received between January and October 2016 by a commercial laboratory, where the initial blood draw did not yield a result and a second sample was drawn between 5 and 28 days after the initial sampling. We included cases with fetal fraction less than 2.8% (the threshold for "no result" in this laboratory) and those with higher fetal fraction but where the NIPT results could not be interpreted with high confidence. RESULTS: For 4,018 cases in which a redraw was recommended, a result was obtained for the second sample in 2,835 cases (70.6%) (95% CI 69.1-72.0%). For the 2,959 cases with insufficient fetal fraction, there was a result for the second sample in 1,861 cases (62.9%) (95% CI 61.1-64.6%). For this subset, the average increase in fetal fraction was 1.2% with an average interval between draws of 14 days. Informative redraw rate was strongly dependent on maternal weight and fetal fraction measured at the first draw. Gestational age was not an important determinant. Informative redraw rate increased rapidly over the first 8 days after the initial draw and more slowly thereafter. CONCLUSION: Based on fetal fraction in the initial sample, maternal weight, and interval between blood draws, women can be provided with a personalized estimate of their likelihood of a result on redraw. This should aid in the counseling of women faced with the choice of reattempting NIPT, conventional screening, or an invasive diagnostic test.