Jacob Cynamon

A Prospective, Single-Arm, Multicenter Trial of Ultrasound-Facilitated, Catheter-Directed, Low-Dose Fibrinolysis for Acute Massive and Submassive Pulmonary Embolism : The SEATTLE II Study

OBJECTIVES This study conducted a prospective, single-arm, multicenter trial to evaluate the safety and efficacy of ultrasound-facilitated, catheter-directed, low-dose fibrinolysis, using the EkoSonic Endovascular System (EKOS, Bothell, Washington). BACKGROUND Systemic fibrinolysis for acute pulmonary embolism (PE) reduces cardiovascular collapse but causes hemorrhagic stroke at a rate exceeding 2%. METHODS Eligible patients had a proximal PE and a right ventricular (RV)-to-left ventricular (LV) diameter ratio ≥0.9 on chest computed tomography (CT). We included 150 patients with acute massive (n = 31) or submassive (n = 119) PE. We used 24 mg of tissue-plasminogen activator (t-PA) administered either as 1 mg/h for 24 h with a unilateral catheter or 1 mg/h/catheter for 12 h with bilateral catheters. The primary safety outcome was major bleeding within 72 h of procedure initiation. The primary efficacy outcome was the change in the chest CT-measured RV/LV diameter ratio within 48 h of procedure initiation. RESULTS Mean RV/LV diameter ratio decreased from baseline to 48 h post-procedure (1.55 vs. 1.13; mean difference, -0.42; p < 0.0001). Mean pulmonary artery systolic pressure (51.4 mm Hg vs. 36.9 mm Hg; p < 0.0001) and modified Miller Index score (22.5 vs. 15.8; p < 0.0001) also decreased post-procedure. One GUSTO (Global Utilization of Streptokinase and Tissue Plasminogen Activator for Occluded Coronary Arteries)-defined severe bleed (groin hematoma with transient hypotension) and 16 GUSTO-defined moderate bleeding events occurred in 15 patients (10%). No patient experienced intracranial hemorrhage. CONCLUSIONS Ultrasound-facilitated, catheter-directed, low-dose fibrinolysis decreased RV dilation, reduced pulmonary hypertension, decreased anatomic thrombus burden, and minimized intracranial hemorrhage in patients with acute massive and submassive PE. (A Prospective, Single-arm, Multi-center Trial of EkoSonic® Endovascular System and Activase for Treatment of Acute Pulmonary Embolism (PE) [SEATTLE II]; NCT01513759).

Hypogastric artery coil embolization prior to endoluminal repair of aneurysms and fistulas: buttock claudication, a recognized but possibly preventable complication.

PURPOSE Hypogastric artery embolization is considered to be necessary to prevent retrograde flow and potential endoleaks when a stent-graft crosses the origin of the hypogastric artery. The authors assess the incidence of buttock claudication, which is the primary complication encountered. The effect of coil location and the presence of antegrade flow at the completion of embolization are evaluated. MATERIALS AND METHODS Hypogastric artery embolization and endoluminal repair of aneurysms and fistulas was performed in 34 patients (30 men; four women) aged 27-91 years (mean, 76 years). Ten patients were being treated for solitary abdominal aortic aneurysms, 13 were being treated for aortoiliac aneurysms, and six patients were being treated for isolated common iliac aneurysms, three for hypogastric artery aneurysms and two for iliac arteriovenous fistulas. Eleven patients had coils placed completely above the bifurcation of the hypogastric artery and 23 patients had coils placed at the bifurcation, or within the branches of the hypogastric artery. Preservation of antegrade flow after embolization was noted in 14 of 34 patients. RESULTS Thirty-four patients underwent stent-graft repair after hypogastric artery embolization. There were two perioperative deaths, three proximal leaks, and one collateral leak. Of the 32 patients who survived the procedure, there was one retrograde leak, even though 13 of 32 (41%) patients had continued antegrade flow at completion of the hypogastric artery embolization. When coils were placed at or in the bifurcation of the hypogastric artery, 12 of 22 (55%) experienced claudication. When coils were placed in the proximal hypogastric artery, one of 10 (10%) claudicated. CONCLUSION It is probably not necessary to completely occlude antegrade flow in the hypogastric artery to prevent a distal endoleak. Buttock claudication is rare when coils are placed in the proximal hypogastric artery rather than at its bifurcation or in its branches.

Utility of embolization or chemoembolization as second-line treatment in patients with advanced or recurrent colorectal carcinoma

Background. Second‐line therapy of patients with colorectal cancer metastatic to the liver is unsatisfactory. One alternative to systemic treatment is therapy directed locoregionally.

Renal Artery Pseudoaneurysm Following Laparoscopic Partial Nephrectomy

OBJECTIVES To present our experience with the management of renal artery pseudoaneurysms following laparoscopic partial nephrectomy (LPN). METHODS Our bi-institutional LPN database of 259 patients from July 2001 to April 2008 was queried for patients diagnosed with a postoperative renal artery pseudoaneurysm. Demographic data, perioperative course, complications, and follow-up studies in identified subjects were analyzed. Postembolization success was defined as symptomatic relief, resolution of hematuria, and a stable hematocrit and serum creatinine. RESULTS We identified 6 patients (2.3%) who were diagnosed with a renal artery pseudoaneurysm after LPN. The mean age of our cohort was 61.2 years (49-76), mean operative time was 208 minutes (140-265), and mean estimated blood loss was 408 mL (50-800). Patients presented at a mean of 12.6 days (5-23) after the initial surgery. Five patients had gross hematuria and a decreased hematocrit, with 1 patient presenting with clinical symptoms of hypovolemia. The sixth patient was incidentally diagnosed. The diagnosis of a renal artery pseudoaneurysm was confirmed in all cases by angiography. Selective angioembolization was successfully performed in all patients. At a median follow-up of 8.3 months all patients (100%) remained without any evidence of recurrence. CONCLUSIONS Although pseudoaneuryms are a rare postoperative complication of LPN, they are potentially life-threatening. Early identification and proper management can help reduce the potential morbidity associated with pseudoaneurysms. Our experience demonstrates the feasibility and supports the use of selective angioembolization as an excellent first-line option for patients who present with this form of delayed bleeding.

Mechanical and enzymatic thrombolysis of acute pulmonary embolus: review of the literature and cases from our institution.

Pulmonary embolism (PE) is a major cause of morbidity and mortality in the United States. Patients with massive PE have a high mortality rate, with two of every three deaths occurring in the first hour. The mainstay of treatment for PE is anticoagulation. However, when the patient is in extremis, intravenous lysis of the clot is indicated. Recently, mechanical fragmentation with or without pharmacologic thrombolysis has been shown to have a role in therapy for patients with massive PE, as well as in those patients who have a contraindication to anticoagulation. We discuss our experience with mechanical fragmentation in the treatment of PE and review the literature.

When Is Urokinase Treatment an Effective Sole or Adjunctive Treatment for Acute Limb Ischemia Secondary to Native Artery Occlusion

BACKGROUND Intra-arterial thrombolytic therapy is currently a therapeutic option for the treatment of acute limb ischemia. A recent large prospective randomized trial (TOPAS) comparing lytic therapy and operative intervention showed that both forms of treatment had similar results in terms of amputation-free survival. However, the exact role for lytic treatment is unclear. METHOD Over a 4-year period we treated 60 cases of acute limb ischemia in 57 patients secondary to native artery occlusion with thrombolytic therapy with urokinase. All patients were evaluated at 1 week, 1 month, and then at 3-month intervals posttreatment. Follow-up evaluations included pulse examination, pulse volume recordings, and duplex examinations to confirm arterial patency. No patients were lost to follow-up with a range of 8 to 54 months (mean 26). RESULTS Of these 60 native arterial occlusions, complete lysis was achieved in 46 cases (76%). Of these 46 cases, 18 required lysis only, 19 cases (9 iliac, 7 superficial femoral artery (SFA), and 3 popliteal) required angioplasty of lesions uncovered by clot lysis, and 9 patients had lysis and angioplasty of iliac arteries followed by infrainguinal bypasses. Eight of the 57 patients (14%) who had been asymptomatic presented with symptoms limited to new onset claudication, all of which were successfully lysed. Cumulative patency for the 43 successful cases was 90% +/- 5% at 1 year and 75% +/- 4% at 2 years. The 1-year amputation-free survival for all native artery occlusions was 85% +/- 6%. CONCLUSION Thrombolysis with urokinase simplified the treatment of native arterial occlusion proving to be the sole therapy in 18 (29%) patients or a valuable adjunct by facilitating the angioplasty of arterial lesions and avoiding open surgery in 60% of patients treated. In addition, the correction of inflow lesions reduced the magnitude of required subsequent bypass procedures to achieve limb salvage. In conclusion, successful thrombolysis of native artery occlusion provided durable arterial patency and limb salvage, particularly in patients with new onset claudication.

Value of Noncontrast CT Immediately after Transarterial Chemoembolization of Hepatocellular Carcinoma with Drug-eluting Beads

PURPOSE To retrospectively evaluate the presence and distribution patterns of contrast agent retention in the liver on noncontrast computed tomography (CT) immediately following chemoembolization with drug-eluting beads (DEBs). MATERIALS AND METHODS From 2008 to 2010, 95 patients with 224 liver lesions had chemoembolization performed with DEBs and a noncontrast CT examination of the liver performed immediately after embolization. Of these, 85 patients with 193 lesions were included. The postembolization CT scan was reviewed by a diagnostic radiologist, and the presence of contrast agent retention within the lesion was assessed. Varying patterns of contrast agent retention were defined. RESULTS Of the 193 lesions included, 146 (76%) retained contrast medium. Aside from some contrast medium in vessels, very little if any contrast medium was seen in the surrounding liver. Various patterns of contrast agent retention were noted within lesions. In a single case, repeat imaging was obtained 6 hours later, which demonstrated washout of contrast agent in a lesion that had retained contrast agent on the postprocedure CT scan. Of significance, 13 additional foci of contrast agent retention were identified on postchemoembolization CT scans that, on retrospective review of preprocedure imaging, represented enhancing lesions not previously identified. CONCLUSIONS Noncontrast CT after chemoembolization with DEBs demonstrates contrast agent retention in 76% of cases, without significant contrast medium seen in the adjacent liver parenchyma. The presence or absence of contrast agent retention may prove to be useful in evaluating accurate targeting of a lesion.

Analysis of Balloon Dilatation of Human Vein Graft Stenoses

Controversy continues as to whether percutaneous transluminal angioplasty (PTA) or surgical revision is the ideal modality for the treatment of failing grafts. This prompted a histopathologic analysis of failing human vein graft segments subjected to ex vivo balloon dilatation to define variables responsible for the discrepant results. Fifteen vein graft lesions from 14 patients with failing infrainguinal bypasses were recovered after surgical excision. Each graft lesion was focal and uniform in length (2.1±0.3 cm). Rings sectioned from adjacent regions of each vein graft lesion before and after balloon inflation were processed for histologic study, photomicrography, and image analysis. Angioplasty balloon size was selected on the basis of preoperative arteriograms. Graft lesions were divided into three groups based on lesion thickness and the degree of fibrosis and cellularity seen on sections stained with Massons trichrome. The luminal area before angioplasty was not significantly different for the three groups (p>0.2). Vein grafts with thick intimas (group 1) had significantly less luminal dilatation after angioplasty as compared with less thick intimal lesions (groups 2 and 3;p<0.001). Those lesions with varying degrees of cellularity (groups 2 and 3) showed no significant differences in luminal diameter after angioplasty. However, the cellular lesions in group 2 consistently formed multiple intimal flaps that could produce PTA failures even with good luminal restoration. The varying histology of vein graft lesions and associated differences in intimal thickness and cellularity may be responsible for the inconsistent results following PTA. Estimates of wall thickness before angioplasty, particularly in the intimal area, may be helpful in evaluating which lesions might benefit most from PTA.

Retained fibrin sheaths: chest computed tomography findings and clinical associations.

Purpose: Fibrin sheaths may develop around long-term indwelling central venous catheters (CVCs) and remain in place after the catheters are removed. We evaluated the prevalence, computed tomographic (CT) appearance, and clinical associations of retained fibrin sheaths after CVC removal. Materials and Methods: We retrospectively identified 147 adults (77 men and 70 women; mean age 58 y) who underwent CT after CVC removal. The prevalence of fibrin sheath remnants was calculated. Bivariate and multivariate analyses were performed to assess for associations between sheath remnants and underlying diagnoses leading to CVC placement; patients’ age and sex; venous stenosis, occlusion, and collaterals; CVC infection; and pulmonary embolism. Results: Retained fibrin sheaths were present in 13.6% (20/147) of cases, of which 45% (9/20) were calcified. Bivariate analysis revealed sheath remnants to be more common in women than in men [23% (16/70) vs. 5% (4/77), P=0.0018] and to be more commonly associated with venous occlusion and collaterals [30% (6/20) vs. 5% (6/127), P=0.0001 and 30% (6/20) vs. 6% (7/127), P=0.0003, respectively]. Other variables were not associated. Multivariate analysis confirmed the relationship between fibrin sheaths and both female sex (P=0.005) and venous occlusion (P=0.01). Conclusions: Retained fibrin sheaths were seen on CT in a substantial minority of patients after CVC removal; nearly half of them were calcified. They were more common in women and associated with venous occlusion.

Transfemoral Transcaval Core-Needle Liver Biopsy: An Alternative to Transjugular Liver Biopsy.

PURPOSE To describe the technique and outcome of transfemoral transcaval (TFTC) core-needle liver biopsies. MATERIALS AND METHODS Retrospective chart review was performed on 121 patients who underwent transvenous liver biopsies at a single institution between February 2014 and July 2015, yielding 66 total TFTC liver biopsies for review (65.2% male; mean age, 53.2 y ± 15.0). From August 2014 through July 2015, TFTC biopsies accounted for 64 of 77 (83%) transvenous biopsies. Hepatic tissue was obtained directly through the intrahepatic inferior vena cava from a femoral venous approach. Procedural complications were classified according to Society of Interventional Radiology guidelines. RESULTS Of the 66 biopsies, technical success was achieved in 64 cases (97.0%). Histopathologic diagnoses were made in 63 cases (95.5%). Fragmented or limited specimens in which a pathologic diagnosis was still made occurred in four cases (6.1%). Complications occurred in two cases (3.0%). Venous pressure measurements were requested in 60 cases, and all were successfully obtained. CONCLUSIONS TFTC core-needle liver biopsies are feasible and safe as demonstrated in this series of patients.