Effectiveness of Intra-operative Contrast-Enhanced Ultrasound Assessment to Optimize Type II Endoleak Embolization.

PURPOSE: To analyze the effectiveness of type II endoleaks (T2E) embolization using intra-operative contrast-enhanced ultrasound (CEUS). METHODS: Consecutive patients treated for T2E underwent a standardized protocol with trans-arterial or trans-lumbar access, large volume embolization, onlay fusion, and intra-operative CEUS. Technical success was defined by exclusion of endoleak by CEUS. RESULTS: Twenty-six patients (mean age 81 ± 11 years old; 89% male) were treated. The mean aneurysm sac enlargement was 11 ± 8 mm from T2E diagnosis. Embolization was performed using Onyx® 18 in all patients with adjunctive coils in 13 patients (50%). After the first embolization, CEUS documented residual T2E in 13 patients (50%). Ten patients (38%) had additional embolization, which successfully eradicated the T2E in seven of them. Technical success was 50% after the first embolization attempt and 77% after additional attempts guided by CEUS (P = 0.080). There was no mortality. Median imaging follow-up was 22 months. Among the 20 patients with no residual T2E on completion CEUS, 16 (80%) had sac stabilization and none required additional interventions for T2E. Of the six patients with residual T2Es on CEUS, three had sac stabilization (50%) and one required additional reintervention for T2E. There was one late aortic rupture at 56 months. CONCLUSION: One in two patients treated by T2E embolization had residual endoleak on intra-operative CEUS after a first embolization attempt, decreasing to one in four patients after multiple attempts. A negative completion CEUS following embolization was associated with higher rates of sac stabilization and no need for additional T2E embolization.

Technical pitfalls and proposed modifications of instructions for use for endovascular aortic aneurysm repair using the Gore Excluder conformable device in angulated and short landing zones.

We describe a case of an abdominal aortic aneurysm (AAA) and angulated proximal neck treated with a Gore Excluder conformable endoprosthesis and show relevant technical pitfalls in the deployment of the graft main body. An 82-year-old man presented with a 71-mm asymptomatic AAA with an angulated infrarenal proximal neck (75°) and was referred to our unit. The patient was treated with a 26-mm Gore Excluder conformable device, which was deployed slightly above the renal arteries after precatheterization of the lowest renal artery. The graft was then repositioned with support of the introducer sheath and a stiff guide wire. The proximal sealing zone was ballooned before the endograft delivery system was retrieved to avoid distal migration. Technical success was achieved. The patient was discharged with no complications. No type Ia endoleak was present on the 6-month computed tomography scan. Endovascular treatment of an AAA with a severe angulated proximal neck can be effective with a conformable stent graft if technical measures are used during deployment of the main body to optimize the seal.

Changes in renal-mesenteric duplex ultrasound velocities after fenestrated and branched endovascular aortic aneurysm repair.

OBJECTIVE: Stenting of renal and mesenteric vessels may result in changes in velocity measurements due to arterial compliance, potentially giving rise to confusion about the presence of stenosis during follow-up. The aim of our study was to compare preoperative and postoperative changes in peak systolic velocity (PSV, cm/s) after placement of the celiac axis (CA), superior mesenteric artery (SMA) and renal artery (RAs) bridging stent grafts during fenestrated-branched endovascular aortic repair (FB-EVAR) for treatment of complex abdominal aortic aneurysms (AAA) and thoracoabdominal aortic aneurysms. METHODS: Patients were enrolled in a prospective, nonrandomized single-center study to evaluate FB-EVAR for treatment of complex AAA and thoracoabdominal aortic aneurysms between 2013 and 2020. Duplex ultrasound examination of renal-mesenteric vessels were obtained prospectively preoperatively and at 6 to 8 weeks after the procedure. Duplex ultrasound examination was performed by a single vascular laboratory team using a predefined protocol including PSV measurements obtained with <60° angles. All renal-mesenteric vessels incorporated by bridging stent grafts using fenestrations or directional branches were analyzed. Target vessels with significant stenosis in the preoperative exam were excluded from the analysis. The end point was variations in PSV poststent placement at the origin, proximal, and mid segments of the target vessels for fenestrations and branches. RESULTS: There were 419 patients (292 male; mean age, 74 ± 8 years) treated by FB-EVAR with 1411 renal-mesenteric targeted vessels, including 260 CAs, 409 SMAs, and 742 RAs. No significant variances in the mean PSVs of all segments of the CA, SMA, and RAs at 6 to 8 weeks after surgery were found as compared with the preoperative values (CA, 135 cm/s vs 141 cm/s [P = .06]; SMA, 128 cm/s vs 125 cm/s [P = .62]; RAs, 90 cm/s vs 83 cm/s [P = .65]). Compared with baseline preoperative values, the PSV of the targeted vessels showed no significant differences in the origin and proximal segment of all vessels. However, the PSV increased significantly in the mid segment of all target vessels after stent placement. CONCLUSIONS: Stent placement in nonstenotic renal and mesenteric vessels during FB-EVAR is not associated with a significant increase in PSVs at the origin and proximal segments of the target vessels. Although there is a modest but significant increase in velocity measurements in the mid segment of the stented vessel, this difference is not clinically significant. Furthermore, PSVs in stented renal and mesenteric arteries were well below the threshold for significant stenosis in native vessels. These values provide a baseline or benchmark for expected PSVs after renal-mesenteric stenting during FB-EVAR.

Technical Pitfalls for Fenestrated-Branched Endovascular Aortic Repair Following PETTICOAT.

PURPOSE: The Provisional Extension to Induce Complete Attachment Technique (PETTICOAT) uses a bare-metal stent to scaffold the true lumen in patients with acute or subacute aortic dissections. While it is designed to facilitate remodeling, some patients with chronic post-dissection thoracoabdominal aortic aneurysms (TAAAs) require repair. This study describes the technical pitfalls of fenestrated-branched endovascular aortic repair (FB-EVAR) in patients who underwent prior PETTICOAT repair. TECHNIQUE: We report 3 patients with extent II TAAAs who had prior bare-metal dissection stents treated by FB-EVAR. Two patients required maneuvers to reroute the aortic guidewire, which was initially placed in-between stent struts. This was recognized before the deployment of the fenestrated-branched device. A third patient had difficult advancement of the celiac bridging stent due to a conflict of the tip of the stent delivery system into one of the stent struts, requiring to redo catheterization and pre-stenting with a balloon-expandable stent. There were no mortalities and target-related events after a follow-up of 12 to 27 months. CONCLUSION: FB-EVAR following the PETTICOAT is infrequent, but technical difficulties should be recognized to prevent complications from the inadvertent deployment of the fenestrated-branched stent-graft component in-between stent struts. CLINICAL IMPACT: The present study highlights a few maneuvers to prevent or overcome possible complications during endovascular repair of chronic post-dissection thoracoabdominal aortic aneurysm following PETTICOAT. The main problem to be recognized is the placement of the aortic wire beyond one of the struts of the existing bare-metal stent. Moreover, encroachment of catheters or the bridging stent delivery system into the stent struts may potentially cause difficulties.

Characterization of Secondary Interventions After Fenestrated-branched Endovascular Repair of Complex Aortic Aneurysms and Its Effect on Quality of Life and Patient Survival.

OBJECTIVE: To assess the impact of secondary intervention (SI) on health-related quality of life (HR-QOL) after fenestrated-branched endovascular aortic repair (FB-EVAR) for complex abdominal aortic aneurysms and thoracoabdominal aortic aneurysms. BACKGROUND: The effect of SI after FB-EVAR on physical and mental HR-QOL has not been described. METHODS: A cohort of 430 consecutive patients enrolled in a prospective, nonrandomized study to evaluate FB-EVAR (2013-2020) was assessed with 1325 short-form 36 HR-QOL questionnaires preoperatively and during follow-up visits. SIs were classified as major or minor procedures. Endpoints included patient survival, freedom from aortic-related mortality (ARM), freedom from SIs, and changes in HR-QOL physical component score (PCS) and mental component score. RESULTS: There were 302 male with mean age 74±8 years treated by FB-EVAR for 133 complex abdominal aortic aneurysms and 297 thoracoabdominal aortic aneurysms. After a mean follow up of 26±20 months, 97 patients (23%) required 137 SIs. At 5 years, freedom from any SI was 64%±4%, including freedom from minor SIs of 77%±4% and major SIs of 87%±3%. There was no difference in patient survival and freedom from ARM at same interval. On adjusted analysis, minor SIs correlated with improved survival. SIs had a negative correlation with PCS ( r =-0.8). There were no significant changes in mental component score with SIs. Predictors for SIs were fluoroscopy time, graft design, and aneurysm sac change. CONCLUSION: SIs were needed in nearly 1 out of 4 patients treated by FB-EVAR with no effect on patient survival or ARM. SI resulted in decline in PCS.

Early Feasibility of Endovascular Repair of Distal Aortic Arch Aneurysms Using Patient-Specific Single Retrograde Left Subclavian Artery Branch Stent Graft.

OBJECTIVE: To describe the feasibility and outcomes of endovascular repair of distal aortic arch aneurysms using a patient-specific stent graft with a pre-loaded single retrograde left subclavian artery (LSA) branch stent graft. METHODS: We reviewed the clinical data and outcomes of consecutive patients enrolled in an ongoing prospective, non-randomized physician-sponsored investigational device exemption study to evaluate the outcomes of endovascular aortic arch repair using patient-specific arch branch stent grafts (William Cook Europe, Bjaeverskov, Denmark) between 2019 and 2022. All patients received a design with triple-wide scallop and a single retrograde LSA branch with a pre-loaded catheter. RESULTS: There were five male patients with median age of 77 years old (72-80) treated using the single LSA branch stent graft. Technical success was achieved in all patients. Median operating time, fluoroscopy time, and total radiation dose area product were 103 (78-134) minutes, 26 (19-39) minutes, and 123 (71-270) mGy.cm2, respectively. There were no 30-day or in-hospital mortality, neurological or other major adverse events (MAEs). During median follow-up of 21 (20-27) months, all patients were alive with patent LSA branches, except for one who died of COVID-19 complications. There was no branch instability or secondary interventions. CONCLUSION: This early feasibility study demonstrates successful endovascular repair of distal aortic arch aneurysms using a patient-specific stent graft with single retrograde LSA branch without technical failures, mortality or neurological events. Larger clinical experience and longer follow-up are needed to determined effectiveness of this approach in patients who need endovascular repair with proximal extension into Zone 2.

Total Transfemoral Percutaneous Endovascular Aortic Arch Repair Using 3-Vessel Inner Branch Stent-Graft.

Endovascular repair has been introduced to decrease the morbidity and mortality associated with open surgical repair of aortic arch pathology. We illustrate total percutaneous transfemoral approach with a 3-vessel inner branch stent-graft to treat aortic arch aneurysm. (Level of Difficulty: Advanced.).

Single-Center Experience with the Femoral-to-Brachial Preloaded Delivery System for Fenestrated-Branched Endovascular Repair of Complex Aortic Aneurysms.

PURPOSE: To assess technical aspects and outcomes of fenestrated-branched endovascular aortic repair (FB-EVAR) using a femoral-to-brachial (FTB) preloaded delivery system (PDS) with two separate configurations. METHODS: Clinical data of all consecutive patients enrolled in a prospective study to evaluate FB-EVAR for complex abdominal and thoracoabdominal aortic aneurysms (CAAAs & TAAA) between 2013 and 2020 were reviewed. Patients treated with FTB-PDS were included. The two configurations included 4 trans-brachial preloaded wires (4BR) or 2 trans-brachial and 2 transfemoral preloaded wires (2BR-2FE). Outcome measures included technical success, procedural metrics, 30-day or in-hospital mortality, major adverse events (MAEs), and target-vessel outcomes. RESULTS: There were 115 patients with a mean age of 73.8 ± 8 years, treated with FTB-PDS. Of these, 62 patients (54%) had 4BR and 53 patients (46%) had 2BR-2FE FTB-PDS. There were 106 TAAA (92%) and 9 CAAAs (8%). Technical success, defined as successful implantation of the stent-graft and all intended target-vessel stents without type I or III endoleak, was 97%, with no differences in total operating time, endovascular time, and radiation dose between groups. There were 3 deaths (3%) at 30 days. MAEs were noticed in 21 patients (18%) with no difference between groups, including new-onset dialysis (2% vs. 4%, P = 0.59), and paraplegia (7% vs. 11%, P = 0.51), for 4BR and 2BR-2FE, respectively. Patient survival and freedom from aortic-related mortality at 2-years were 79 ± 5% and 97 ± 1.7%, respectively, with no difference between groups. CONCLUSION: The use of FTB-PDS for FB-EVAR is safe with high technical success and a reasonable rate of MAEs. Each configuration provides specific benefits based on patient anatomy, while having similar procedural metrics and clinical outcomes.

Popliteal cysts are not a risk factor for lower extremity deep vein thrombosis.

BACKGROUND: Popliteal cysts (PC) result from distension of the gastrocnemio-semimembranosous bursa. Published reports indicate coincident PC and deep vein thrombosis (DVT). Whether the presence of PC increase the risk of deep vein thrombosis (DVT) remains unclear. METHODS: Lower extremity venous Duplex ultrasound (DUS) reports were evaluated across the Mayo Clinic Enterprise (Rochester, Minnesota, Jacksonville, Florida, Scottsdale, Arizona, and the Mayo Clinic Health System) in patients ≥ 18 years of age. Natural language processing (NLP) algorithms were created and validated to identify acute lower extremity DVT and PC from these reports. To determine whether there is a link between PC and lower extremity DVT, the frequency of PC among cases (ultrasounds with acute DVT) were compared to controls (ultrasounds without acute DVT). RESULTS: A total of 357,703 lower extremities venous DUS were performed in 237,052 patients (mean age 63.3 ± 16.6, 54.4% were female) between 1992 and 2021. Acute DVT was identified in 32,572 (9.1%) DUS, and PC in 32,448 (9.1%). PC were seen in a lower frequency (8.0%) of ultrasounds with acute DVT than those without (9.2%) acute DVT (OR: 0.85, 95% CI: 0.82 to 0.89, p < 0.001). In a multivariate logistic regression model after adjusting for age, sex, and race, PCs were not positively associated with acute DVT (adjusted OR: 0.84, 95% CI: 0.81 to 0.88). CONCLUSIONS: PC are an incidental finding or an alternative diagnosis on lower extremity venous DUS, a finding that increases significantly with age. PC were not a risk factor in the development of lower extremity DVT.

Impact of gap distance between fenestration and aortic wall on target artery instability following fenestrated-branched endovascular aortic repair.

OBJECTIVE: Target artery (TA) instability has been the most frequent indication for secondary intervention after fenestrated and branched endovascular aortic repair (FB-EVAR) of pararenal and thoracoabdominal aortic aneurysms (TAAAs). The aim of the present study was to evaluate the effect of the gap distance between the endograft reinforced fenestration and TA origin at the aortic wall (fenestration gap [FG]) on target-related outcomes after FB-EVAR. METHODS: The clinical data and imaging studies of 430 patients enrolled in a prospective, nonrandomized study to evaluate FB-EVAR using manufactured stent grafts were reviewed. Of the 430 patients, 340 (79%) had had more than one vessel incorporated by fenestration. The FG was retrospectively measured on postoperative imaging studies and classified into three groups: no gap (FG, 0 mm), FG 1 to 4 mm, and FG ≥5 mm. The primary outcome was freedom from TA instability. The secondary end points included TA-related endoleak, TA secondary intervention, and TA patency. RESULTS: A total of 1558 renal-mesenteric TAs were incorporated by 1104 reinforced fenestrations and 454 directional branches (DBs), with a mean of 3.9 ± 0.5 vessels per patient. The mean FG was 2.8 ± 4.5 mm, with an FG of 0 mm for 646 TAs, 1 to 4 mm for 209 TAs, and ≥5 mm for 249 TAs. An FG of ≥5 mm was associated with significantly lower (P < .001) freedom from TA instability, type Ic or IIIc endoleak, and secondary interventions at 5 years. Compared with DBs, fenestrations with an FG of ≥5 mm had similar primary patency and freedom from TA instability but significantly lower freedom from type Ic or IIIc endoleak (91% ± 2% vs 95% ± 1%; log rank, P = .02) and secondary interventions (87% ± 3% vs 93% ± 2%; log-rank, P = .02) at 5 years. The independent predictors of TA instability included postdissection TAAAs (hazard ratio, 2.5; 95% confidence interval, 1.2-5.4) and FG ≥5 mm (hazard ratio, 1.6; 95% confidence interval, 1.2-1.8). TAs incorporated by reinforced fenestrations had higher primary (99% ± 0.8% vs 97% ± 1.0%; P = .039) and secondary (100% vs 98% ± 1.0%; P = .012) patency rates at 5 years compared with DBs, with the lowest primary patency observed for renal DBs (80% ± 6% vs 92% ± 2%; P = .008). CONCLUSIONS: An FG of ≥5 mm was independently associated with an increased risk of TA instability, type Ic or IIIc endoleaks, and secondary interventions for patients treated by FB-EVAR using fenestrated designs. TAs incorporated by DBs had lower 5-year primary and secondary patency compared with those with reinforced fenestrations, with the lowest 5-year patency of 80% for renal branches. Compared with DBs, fenestrations with an FG of ≥5 mm carried a greater risk of type Ic or IIIc endoleak and secondary interventions. Independent predictors of TA instability included postdissection TAAAs and a greater FG. In contrast, dual antiplatelet therapy and larger TA diameters were protective.

Incidence, predictive factors, and outcomes of intraprocedure adverse events during fenestrated-branched endovascular aortic repair of complex abdominal and thoracoabdominal aortic aneurysms.

OBJECTIVE: To evaluate the incidence of intraoperative adverse events (IAEs) and their impact on outcomes after fenestrated-branched endovascular aortic repair (FB-EVAR) of complex abdominal aortic aneurysms and thoracoabdominal aortic aneurysm (TAAAs). METHODS: We reviewed the clinical and imaging data of 600 consecutive patients (445 males; mean age, 75 ± 8 years) who underwent FB-EVAR between 2007 and 2019 in a single institution. IAE was defined as any intraoperative complication or technical problem requiring additional and unplanned procedures, and was classified as access-related, target artery (TA)-related, or graft-related. End points included rates of IAEs, 30-day or in-hospital mortality, major adverse events, patient survival, freedom from secondary intervention, and TA instability. RESULTS: A total of 122 IAEs were identified in 105 patients (18%). IAEs were TA-related in 55 patients (9%), access-related in 46 patients (8%), and graft-related in seven patients (1%). Female sex was more frequent among patients with IAEs (44% vs 22%; P < .001). Patients with IAEs had smaller renal artery diameter (-0.4 mm, 5.4 ± 0.8 mm vs 5.8 ± 0.9 mm; P < .001), and were treated more often for TAAAs (72% vs 54%; P < .03). Technical success was achieved in 96.5% of patients and was lower for patients with IAEs (82% vs 99%; P < .001). Major adverse events were significantly more frequent among patients who had IAEs (odds ratio [OR], 1.98; 95% confidence interval [CI], 1.21-3.25), most due to acute kidney injury (27% vs 11%; P < .001) including new-onset dialysis (5% vs 1%; P = .01). On multivariate logistic regression model, female sex (OR, 2.5; 95% CI, 1.5-4.0), TA stenosis >50% (OR, 2.0; 95% CI, 1.3-3.3), and Crawford Extent II TAAA (OR, 1.9; 95% CI, 1.1-3.3) were predictive of IAEs, whereas preloaded design (OR, 0.6; 95% CI, 0.4-0.9) and TA diameter (+1 mm; OR, 0.6; 95% CI, 0.4-0.9) were protective of IAEs. IAEs negatively affected secondary intervention (hazard ratio [HR], 1.6; 95% CI, 1.1-2.3) and TA instability (HR, 2.5; 95% CI, 1.2-5.4); however, IAEs did not affect patient survival (HR, 1.0; 95% CI, 0.7-1.4). CONCLUSIONS: IAEs are common, occurring in nearly one of five patients treated with FB-EVAR for complex aortic aneurysms, and have a negative impact on clinical outcomes. IAEs were associated with female sex, TA diameter, and more extensive aortic disease.

Midterm Outcomes of a Prospective, Nonrandomized Study to Evaluate Endovascular Repair of Complex Aortic Aneurysms Using Fenestrated-Branched Endografts.

OBJECTIVE: The aim of this study was to investigate the midterm outcomes of fenestrated and branched endovascular aortic repair (FB-EVAR) of pararenal (PRA) and thoracoabdominal aortic aneurysms (TAAAs). SUMMARY BACKGROUND DATA: FB-EVAR has been associated with decreased morbidity compared to open repair, but there is limited midterm data. METHODS: A total of 430 patients (302 males, mean age 74 ±â€Š8 years) treated by FB-EVAR were enrolled in a prospective, nonrandomized investigational device exemption study. Endpoints included 30-day mortality and major adverse events (MAEs), freedom from all cause and aortic-related mortality, target vessel patency, and freedom from secondary intervention and target vessel instability. RESULTS: There were 133 PRAs and 297 TAAAs with 1673 renal-mesenteric arteries incorporated by fenestrations or directional branches (3.9 ±â€Š0.5 vessels/patient). At 30 days or within the hospital stay if longer than 30 days, there were 4 (0.9%) deaths. MAEs included new-onset dialysis in 8 patients (2%), permanent paraplegia or stroke in 10 patients each (2%), and respiratory failure requiring tracheostomy in 2 patients (0.5%). After a mean follow-up of 26 ±â€Š20 months, there were 3 (0.7%) aortic-related deaths from SMA stent occlusion, gastrointestinal hemorrhage, or complications of open arch repair. At 5 years, freedom from all-cause and aortic-related mortality were 57% ±â€Š5% and 98% ±â€Š1%, respectively. Freedom from secondary intervention was 64% ±â€Š4%, primary target vessel patency was 94% ±â€Š1%, and freedom from target vessel instability was 89% ±â€Š2% at same interval. One patient (0.2%) had nonfatal aneurysm treated using endovascular repair. CONCLUSION: FB-EVAR is safe and effective for treatment of PRA and TAAAs with low rate of aortic-related mortality and aneurysm rupture on midterm follow-up.

Incorporation of Celiomesenteric Trunk With Double Kissing Directional Branches During Fenestrated-Branched Endovascular Aortic Repair.

PURPOSE: Common celiomesenteric trunk (CMT) is a rare anatomical variation that occurs in 0.5% to 3.4% of the general population. Its presence may complicate planning and implantation of fenestrated and branched stent-grafts because the wide diameter and short length of the CMT to its bifurcation does not allow sufficient sealing for placement of bridging stents. CASE REPORT: We report a patient with thoracoabdominal aortic aneurysm (TAAA) and CMT treated by fenestrated-branched endovascular aortic repair (FB-EVAR) using double kissing directional branches to incorporate the celiac axis and superior mesenteric artery. Pitfalls of stent design and implantation are outlined. CONCLUSION: Double kissing directional branches should be considered as an alternative to incorporate vessels with early bifurcation such as a CMT.

Calf Vein Thrombosis Outcomes Comparing Anticoagulation and Serial Ultrasound Imaging Management Strategies.

OBJECTIVE: To compare outcomes among patients with calf deep vein thrombosis (DVT) stratified by management strategy because distal or calf DVT is said to have low rates of propagation, embolization, and recurrence and, as such, guideline recommendations include provisions for serial imaging without treatment. PATIENTS AND METHODS: Consecutive patients with ultrasound-confirmed acute DVT involving the calf veins (January 1, 2016, to August 1, 2018) were identified by scrutinizing the Gonda Vascular Center Ultrasound database. Patients were segregated into 2 categories depending on management strategy; anticoagulation vs serial surveillance ultrasound without anticoagulation. Outcomes including venous thromboembolism (VTE) recurrence, bleeding, death, and net clinical benefit were compared by treatment strategy. RESULTS: There were 483 patients with calf DVT identified; 399 were treated with anticoagulation therapy and 84 were managed with surveillance ultrasound. Patients in the surveillance group were older (70.0±13.9 vs 63.0±14.9 years; P<.001) and more likely to have had a recent hospitalization (76.2% [64/84] vs 45.4% [181/399]; P<.001). Common reasons for choosing ultrasound surveillance included guideline prescriptive (58.3% [49/84]), active bleeding (21.4% [18/84]), and recent surgery (17.9% [15/84]). The VTE recurrence composite was lower for patients treated with anticoagulants (7.3% [29/399]) compared with surveillance (14.3% [12/84]; P=.04). The DVT propagation was less frequent in the treated group (2.8% [11/399] vs 8.3% [7/84]; P=.01). There was no difference in bleeding or mortality outcomes by management strategy. Net clinical benefit (VTE recurrence plus major bleeding) favored anticoagulant therapy (9.8% [39/399] vs 20.2% [17/84]; P<.01). CONCLUSION: Patients with calf DVT treated with anticoagulants had significantly better outcomes compared with those managed by a strategy of serial ultrasound surveillance without increasing bleeding outcomes.