Michael J. Singh

Comparative Outcomes of Ultrasound-Assisted Thrombolysis and Standard Catheter-Directed Thrombolysis in the Treatment of Acute Pulmonary Embolism

Objectives: The objective of this study was to compare the outcomes of patients undergoing ultrasound-accelerated thrombolysis (USAT) and standard catheter-directed thrombolysis (CDT) for the treatment of acute pulmonary embolism (PE). Methods: The records of all patients in our institution having undergone CDT or USAT for massive or submassive PE from 2009 to 2014 were retrospectively reviewed. Standard statistical methods were used to compare characteristics and to assess for longitudinal change in outcomes. Results: Sixty-three patients, 27 CDT and 36 USAT, were treated for massive (12.7%) or submassive (87.3%) PE. Of which, 96.8% were treated for bilateral PE. Baseline patient characteristics did not differ between the 2 treatment groups. There was no difference in total dose of lytic administered (CDT: 23.2 ± 13.7 mg; USAT: 27.5 ± 12.9 mg; P = .2). Two patients in the CDT and 1 in the USAT groups required conversion to surgical thrombectomy (CDT: 7.4%; USAT: 2.8%; P = .6). Rates of major and minor bleeding complications (CDT: 11.0%; USAT: 13.9%; P = .8) did not differ significantly between the CDT and USAT groups. Estimated survival at 90 days was 92% for CDT and 93% for USAT and 82% at 1 year for both groups (P = .8). All echocardiographic parameters improved significantly from baseline to 1-year follow-up, but quantitative improvement did not differ between groups. Conclusion: This study suggests no statistical differences in clinical and hemodynamic outcomes or procedural complication rates between USAT and standard CDT for the treatment of acute PE. Prospective studies are needed to further evaluate comparative and cost-effectiveness of different interventions for acute massive and submassive PE.

Contemporary outcomes of open and endovascular popliteal artery aneurysm repair

OBJECTIVE The purpose of this study was to evaluate contemporary practice and outcomes of open repair (OR) or endovascular repair (ER) for popliteal artery aneurysms (PAAs). METHODS Consecutive patients with PAA treated at one institution from January 2006 to March 2014 were reviewed under an Institutional Review Board-approved protocol. Demographics, indications, anatomic characteristics, and outcomes were collected. Standard statistical methods were used. RESULTS A total of 186 PAAs were repaired in 156 patients (110 ORs, 76 ERs) with a mean age of 71 ± 11 years, and most were male (96%). Mean follow-up was 34.9 ± 28.6 months for OR and 28.3 ± 25.8 months for ER (P = .12). Comorbidities were similar between groups. OR was used in more patients with PAA thrombosis (41.8% vs 5.3%; P < .001), acute ischemia (24.5% vs 9.2%; P = .010), and ischemic rest pain (34.5% vs 6.6%; P < .001). Mean tibial (Society for Vascular Surgery) runoff score was 5.0 for OR vs 3.3 for ER (P = .006). OR was associated with increased 30-day complications (22% vs 2.6%; P < .001) and mean postoperative stay (5.8 vs 1.6 days; P < .001). There was no difference in 30-day mortality (OR, 1.8%; ER, 0%; P = .56) or major amputation rate (OR, 3.7%; ER, 1.3%; P = .65). Primary, primary assisted, and secondary patency rates were similar at 3 years (OR, 79.5%, 83.7%, and 85%; ER, 73.2%, 76.3%, and 83%; P = NS). Among 130 patients presenting electively without acute ischemia or thrombosed PAA (63 ORs and 67 ERs), OR had better 3-year primary patency (88.3% vs 69.8%; P = .030) and primary assisted patency (90.2% vs 73.5%; P = .051) but similar secondary patency (90.2% vs 82%; P = .260). ER thrombosis was noted in 8 of 24 patients treated in 2006-2008 (33%; mean time to failure, 49 months) but in only 4 of 51 patients treated in 2009-2013 (7.8%; mean time to failure, 30 months), suggesting a steep learning curve. CONCLUSIONS ER is a safe and durable option for PAA, with lower complication rates and a shorter length of stay. OR has superior primary patency in patients treated electively but no difference in midterm secondary patency and amputations.

Equivalent Outcomes Between Ultrasound-Assisted Thrombolysis and Standard Catheter-Directed Thrombolysis for the Treatment of Acute Pulmonary Embolism.

Methods: Patients with VLU were subdivided into INFL (n 1⁄4 32) or GRAN (n 1⁄4 16) on the basis of the clinical examination of an active INFL wound with sloughing, tissue necrosis, lack of granulating ulcer base, or active GRAN wound base. CVUWF was collected by applying cotton gauze to the ulcer bed until saturated. The CVUWF was transferred in a collecting tube without additives or antiproteases and centrifuged at 10,000 g, and the supernatant was stored at 80 C. Aliquots were then tested in duplicate, and the concentrations of MMP-1 (collagenase 1), MMP-2 (gelatinase A), MMP-3 (stromelysin 1), MMP-7 (matrilysin 1), MMP-8 (collagenase 2), MMP-9 (gelatinase B), MMP-10 (stromelysin 2), MMP-12 (metalloelastase), and MMP-13 (collagenase 3) were quantified by multiplex enzyme-linked immunosorbent assay. MMP concentration was expressed in pg/mL as mean 6 standard error of the mean. To determine pain in INFL and GRAN wounds, a visual analog scale was used. Nonparametric statistical tests were used to determine significance at P < .05. Results: The mean age of the INFL was 69.1 6 14.8 years (aged 4391 years), and the GRAN was 77.8 6 6.5 years (aged 65-85 years). The CVUWF from INFL VLU contained significantly higher levels of MMP2, MMP-9, and MMP-12, that is, characteristic of MMPs in a degrading wound; however, the CVUWF from GRAN VLU contained higher levels of MMP-1, MMP-7, and MMP-13, which are characteristic MMPs of a reparative and fibroblast proliferating wound (Table). There were no statistically significant differences in MMP-3, MMP-8, or MMP-10. Visual analog scale score of INFL VLU was significantly higher than that in GRAN VLU (5.0 6 0.24 vs 3.4 6 0.29; P 1⁄4 .0003). Conclusions: These data suggest the identification of different kinds of VLU microenvironments consisting of a harmful inflammatory phase with high expressionof degradingMMPsand a reparativemicroenvironment dominated by a granulating phase with expression of proliferating and remodeling MMPs. Consistent with INFL VLU stage, higher pain levels were observed. These results suggest a potential use of MMP panels as useful biomarkers to determine VLU wound condition and to guide best medical treatment. Further researchonMMPs inCVUWFis needed todetermine howMMPprofiles change in the microenvironment of healing vs nonhealing VLUs.

Midterm outcomes of catheter-directed interventions for the treatment of acute pulmonary embolism

Objective The hemodynamic benefits of catheter-directed thrombolysis for acute pulmonary embolism have not been clearly defined beyond the periprocedural period. The objective of this study is to report midterm outcomes of catheter-directed thrombolysis for treatment of acute pulmonary embolism. Methods Records of all patients undergoing catheter-directed thrombolysis for high- or intermediate-risk pulmonary embolism were retrospectively reviewed. Endpoints were clinical success, procedure-related complications, mortality, and longitudinal echocardiographic parameter improvement. Results A total of 69 patients underwent catheter-directed thrombolysis (mean age 59 ± 15 y, 56% male). Eleven had high-risk and 58 intermediate-risk pulmonary embolism. Baseline characteristics did not differ by pulmonary embolism subtype. Fifty-two percent of patients underwent ultrasound-assisted thrombolysis, 39% standard catheter-directed thrombolysis, and 9% other interventional therapy; 89.9% had bilateral treatment. Average treatment time was 17.7 ± 11.3 h with average t-Pa dose of 28.5 ± 19.6 mg. The rate of clinical success was 88%. There were two major (3%) and six minor (9%) periprocedural bleeding complications with no strokes. All echocardiographic parameters demonstrated significant improvement at one-year follow-up. Pulmonary embolism-related in-hospital mortality was 3.3%, and estimated survival was 81.2% at one year. Conclusions Catheter-directed thrombolysis is safe and effective for treatment of acute pulmonary embolism, with sustained hemodynamic improvement at one year. Further prospective large-scale studies are needed to determine comparative effectiveness of interventions for acute pulmonary embolism.

The Treatment of Venous Disease in North America

During the past 15 years treatment of chronic venous insufficiency (CVI) has dramatically changed in North America. In the US, approximately 13 % of men and 22 % of women have venous insufficiency as determined by the San Diego Population Study (Robertson et al., Phlebology 23:103–111, 2008). The advent of minimally invasive vein procedures combined with reimbursement charges have created a paradigm shift in the treatment of CVI. Since 2008, there has been a significant increase in the number of office based procedures and now these represent the standard of care. The increase of office procedures is presumed to be due to an expanding number of non-surgical specialists performing vein procedures, changes in office based reimbursement patterns, industry sponsored advertising and the advancement of technology. The Society for Vascular Surgery (SVS), American Venous Forum (AVF) and American College of Phlebology (ACP) have published guidelines for the treatment of CVI, emphasizing the importance of initial conservative therapy followed by minimally invasive endovascular interventions for patients that have failed to respond favorably (Gloviczki et al., J Vasc Surg 53:2S–48S, 2011; Eklof et al., J Vasc Surg 40:1248–1252, 2004). Technology advancements appear to have increased patient satisfaction and improved the morbidity associated with vein procedures. It’s apparent that therapeutic treatment options should cater to the individual all the while establishing realistic expectations for each patient. Recently, the US Food and Drug Administration approved several new venous treatment methods that may complement or replace current vein treatments. Guidance for future treatment of CVI will require updated societal guidelines, site accreditation, physician certification and large-scale randomized control trials.

Endovascular Repair of an Iliac Ureteroarterial Fistula with Late Stent Thrombosis and Migration into the Bladder

BACKGROUND Ureteroarterial fistulas are rare. We describe a case of ureteral-arterial fistulas (UAF) repaired with an endovascular stent graft and examine late complications associated with the procedure. CASE REPORT A 37-year-old woman with a history of complicated locally invasive cervical cancer treated with chemoradiation presented initially with right leg rest pain and chronic intermittent gross hematuria. She was found to have an ureteroarterial fistula and underwent successful endovascular exclusion with a covered stent with resolution of her symptoms. She returned 1 year later with stent-graft thrombosis manifesting as lower extremity rest pain, requiring a femoral-femoral bypass. She then returned 6 months later with imaging evidence of extravascular migration of the stent graft into the bladder. Because of a poor prognosis of recurrent gynecologic cancer, extraction was not attempted, and she underwent complete urinary diversion. CONCLUSIONS UAFs are a rare occurrence but may be treated successfully with endovascular stent grafting. Despite technical success, late complications such as stent thrombosis may occur even with anticoagulation. Extravascular stent migration may occur in the presence of a chronically dilated ureter.

Outcomes of infrageniculate retrograde versus transfemoral access for endovascular intervention for chronic lower extremity ischemia

Objective: Retrograde infrageniculate access is an alternative treatment strategy for patients who have failed to respond to antegrade endovascular intervention. This study compares the outcomes of infrageniculate retrograde arterial access with the conventional transfemoral access for the endovascular management of chronic lower extremity ischemia. Methods: This was a retrospective single‐center review of retrograde endovascular intervention (REI) from 2012 to 2016. Indications for intervention, comorbidities, complications, procedural success, limb outcomes, and mortality were analyzed. Technical failure was defined as the inability to complete the procedure because of failed access or unsuccessful recanalization. Infrageniculate access and transfemoral access were obtained with ultrasound or angiographic roadmap guidance. Patency rates were calculated for technically successful interventions. Results: There were 47 patients (85% presenting with critical limb ischemia) who underwent sheathless REI after failed antegrade recanalization of TransAtlantic Inter‐Society Consensus class D infrainguinal lesions, whereas 93 patients (83% with critical limb ischemia) underwent standard transfemoral access. There were 16 (34%) femoropopliteal, 14 (30%) tibial, and 17 (36%) multilevel interventions in the retrograde group compared with 41 (41%) femoropopliteal, 20 (20%) tibial, and 39 (39%) multilevel interventions in the transfemoral group. Access sites for the retrograde group included the dorsalis pedis (26%), midcalf peroneal (24%), anterior tibial (22%), posterior tibial (26%), and popliteal (2%) arteries. Overall technical success was achieved in 57% of the retrograde group compared with 78% of the transfemoral group. Mean follow‐up was 20 months (range, 1‐45 months). There were no significant differences in the primary patency rates between the two groups at 1 year and 2 years. The primary assisted patency rates were significantly better in the transfemoral group at 1 year (66% vs 46%; P = .031) and 2 years (56% vs 29%; P = .031). The secondary patency rates were higher in the transfemoral group at 1 year (93% vs 83%; P = .079) and 2 years (91% vs 76%; P = .079), although this did not reach statistical significance. The rate of reintervention was 41% for the retrograde group vs 40% for the transfemoral group. Most of the reinterventions (70% in the retrograde group and 61% in the transfemoral group) were endovascular interventions for a restenosis or occlusion. Conclusions: Infrageniculate access for REI can result in primary patency rates similar to those of antegrade interventions and does not compromise the access site. Technical failure is high in this initial experience and is mostly due to failed recanalization. Limb salvage may be achieved after technical failure with either repeated antegrade intervention or surgical bypass.

Occult type I or III endoleaks are a common cause of failure of type II endoleak treatment after endovascular aortic repair

Objective Most type II endoleaks have a benign natural history, but 6% to 8% are associated with sac enlargement and respond poorly to treatment. Our aim was to evaluate whether these enlargements are associated with delayed or occult type I and III endoleaks. Methods Patients with interventions for endoleak after endovascular aortic repair from 2000 to 2016 were reviewed retrospectively. Patient demographics, comorbidities, endoleak type, secondary procedures, aortic sac growth (≥5 mm), and mortality were collected. Successful treatment was defined as endoleak resolution with no further aortic sac growth. Secondary procedures, ruptures, endograft explant, and death were captured. Results There were 130 patients diagnosed with a primary type II endoleak after endovascular aortic repair at a median of 1.3 months (interquartile range, 1.0‐13.3 months). One hundred eighteen had their initial treatment for a primary type II. Twelve of the 130 were initially stable and observed, but were treated for a delayed type I or III endoleak. The 130 patients underwent 279 procedures for endoleaks (mean of 2.2 ± 1.3) over 6.9 ± 3.8 years of follow‐up. Of the 118 patients treated for primary type II endoleaks, 26 (22.0%) later required interventions for delayed type I and III endoleaks. The mean time to intervention for a delayed type I or III endoleak was 5.4 ± 2.8 years. Overall, there were 16 type IA, 11 type IB, 2 type III, 7 combined type IA/IB, and 2 type IA/III delayed endoleaks. The odds of harboring a delayed type I or III endoleak was 22.0% before the first attempt at type II endoleak treatment, 35.1% before the second, 44.8% before the third, and 66.6% before the fourth attempts. Rapid aortic sac growth of ≥5 mm/y before initial endoleak treatment was associated with increased risk for delayed type I or III endoleak (47.8 vs 14.1%; P = .003). Patients with delayed type I or III endoleaks had a lower successful treatment rate (8.3% vs 52.3%; P = .001) than those with only type II endoleaks. Late rupture was increased with delayed type I or III endoleak (P = .002), whereas mortality (P = .96) and aortic‐related mortality (P = .46) were similar. Graft explant (P = .06) trended toward an increase with a delayed type I or III endoleak, but was not statistically significant. Conclusions Failed attempts treating type II endoleaks and/or a rapid aortic sac growth of 5 mm/y or greater should raise the suspicion of a delayed or occult type I or III endoleak. Occult endoleaks are associated with decreased chance of endoleak resolution.

Incidental posterior mediastinal paraganglioma: The safe approach to management, case report

Highlights • Mediastinal paragangliomas are extremely rare and their diagnosis and management can be challenging.• These tumors are classified as functional or non-functional according to their ability to produce and release catecholamines.• Appropriate laboratory studies should be done prior to biopsy or surgical resection to avoid complications.• Complete surgical resection continues to be the standard of care for patients diagnosed with mediastinal paraganglioma.• Surgeons must consider catecholamine-secreting tumors as a differential diagnosis of mediastinal lesions.