Frank P. McGrath

Interventional radiology in the diagnosis, management, and follow-up of pseudoaneurysms.

Arterial wall disruption, as a consequence of inflammation/infection, trauma (penetrating or blunt), or iatrogenic causes, may result in pseudoaneurysm formation. Currently, iatrogenic causes are increasing as a result of the growth of endovascular intervention. The frequency of other causes also seems to be increasing, but this may simply be the result of increased diagnosis by better imaging techniques, such as multidetector contrast-enhanced computed tomography. Clinically, pseudoaneurysms may be silent, may present with local or systemic signs, or can rupture with catastrophic consequences. Open surgical repair, previously the mainstay of treatment, has largely been replaced by image-guided occlusion methods. On the basis of an experience of over 100 pseudoaneurysms, treatments at various anatomical sites, imaging modalities used for accurate diagnosis, current changing therapeutic options for pseudoaneurysm management, approved embolization agents, and clinical follow-up requirements to ensure adequate treatment will be discussed. Image-guided direct percutaneous and endovascular embolization of pseudoaneurysms are established treatment options with favorable success rates and minimal morbidity. The pendulum has now swung from invasive surgical repair of pseudoaneurysms to that of image-guided interventional radiology.

A Prospective Comparison of Two Types of Tunneled Hemodialysis Catheters: The Ash Split Versus the PermCath

Purpose: In a prospective randomized study a standard dual-tip hemodialysis catheter (PermCath, Sherwood Medical, St. Louis, MO, USA) was compared with a newer split-lumen catheter (Ash Split, Medcomp, Harleysville, PA, USA).Methods: Sixty-nine patients (42 men, 27 women; mean age 62 years) were randomized to receive either the Ash Split (AS) or the PermCath (PC) catheter. The catheters were inserted into the internal jugular vein. The primary outcome evaluated was blood flow measurements during the first six hemodialysis sessions. Secondary outcomes included: technical difficulties encountered at insertion, early complications and late complications requiring catheter removal or exchange.Results: A total of 69 hemodialysis catheters, 33 AS and 36 PC, were successfully inserted in the internal jugular vein (right 60, left 9) of 69 patients. Mean blood flow during dialysis (Qb) was 270.75 ml/min and 261.86 ml/hr for the AS and PC groups respectively (p = 0.27). Mean duration of catheter use was 111.7 days (range 5.4–548.9 days) and 141.2 days (range 7.0–560.9 days) in the AS and PC groups respectively (p = 0.307). Catheter failures leading to removal or exchange occurred in 20 patients: 14 in the AS group and six in the PC group. Survival curves with censored endpoints (i.e., recovery, arteriovenous fistula formation, peritoneal dialysis and transplantation) showed significantly better outcome with PermCath catheters (p = 0.024). There was no significant difference in ease of insertion or early complication rates.Conclusion: The Ash Split catheter allows increased rates of blood flow during hemodialysis but this increase was not significant at the beginning (p = 0.21) or end (p = 0.27) of the first six hemodialysis sessions. The Ash Split catheter is more prone to minor complications, particularly dislodgment, than the PermCath catheter.

De Novo Placement of Button Gastrostomy Catheters in an Adult Population: Experience in 53 Patients

PURPOSE To investigate the feasibility of primary button gastrostomy insertion with the aid of T-fastener gastropexy. MATERIALS AND METHODS Fifty-three consecutive patients (33 men, 20 women; mean age, 63.4 years) referred for percutaneous radiologic gastrostomy (PRG) underwent primary button gastrostomy insertion over an 18-month period in two centers. Nine of the patients (17%) were referred after failed endoscopic gastrostomy and 44 (83%) were primarily referred for PRG. Indications for gastrostomy included esophageal/head and neck malignancy (n = 33) and neurologic disorders (n = 20). Gastropexy with three or four T-fasteners was performed in all patients and angioplasty balloon catheters (6 mm x 40 mm) were used to measure tract length and dilate the tract. An 18-F dilator was used for final tract dilation. Button gastrostomy catheters with retention balloons were inserted in all patients. Patient follow-up was performed by the department of dietetics, which contacted patients on a weekly basis. RESULTS Primary button gastrostomy insertion was successful in 52 of 53 patients (98%). The mean gastrostomy button catheter survival was 13.3 weeks (range, 1-28 weeks). No episodes of button occlusion occurred. Since the beginning of this study, 33 patients (63%) have had their gastrostomy buttons replaced. The reasons for button replacement include burst retention balloons (n = 27; 52%), dislodgment of the catheter (n = 4; 8%), and continuing pain/discomfort at the gastrostomy site (n = 2; 4%). CONCLUSION Button-type gastrostomy catheters can be placed de novo by interventional radiologists without the need for a mature tract, provided a T-fastener gastropexy is used. The balloon retention button devices are not compromised by occlusion but do tend to become dislodged.

Subintimal Angioplasty: Predictors of Long-term Success

PURPOSE To determine the clinical outcomes and success rates after percutaneous subintimal angioplasty (SIA) in patients with lower-limb occlusive lesions causing intermittent claudication (IC) or critical limb ischemia (CLI) at midterm to long-term follow-up. The secondary aim was to elicit factors predictive of a successful outcome. MATERIALS AND METHODS Between January 1999 and June 2006, 75 consecutive patients (45 men; age range, 46-91 years; CLI in 79%) underwent SIA of iliac and infrainguinal (84%) occlusions. Outcomes were determined on an intent-to-treat basis. The composite endpoint of interest was major adverse clinical outcome (MACO) of the treated limb at follow-up, which was defined as the development of IC, CLI, or need for subsequent endovascular or surgical revascularization. Actuarial freedom from MACO was assessed via Kaplan-Meier curves and multivariable Cox proportional-hazards regression. RESULTS SIA was performed on 75 lesions, with an initial procedure success rate of 83% (n = 62). Procedure failure was caused by heavily calcified lesions (n = 5) and failure of reentry (n = 8). A total of 56.3% of patients with claudication were free from ipsilateral claudication at follow-up (mean, 32 months; range, 1-64 months), and those with CLI had a 79.7% limb salvage rate at a mean follow-up of 30.7 months (range, 0.5-91 months). On Cox regression analysis, the following variables were identified as independent predictors of MACO within the limb treated with SIA: ABI after SIA (hazard ratio, 0.21; 95% CI, 0.05-0.89; P = .035) and number of patent runoff vessels (ie, </=1 vs >/=2; hazard ratio, 0.29; 95% CI, 0.15-0.59; P = .001). CONCLUSIONS SIA is a feasible therapeutic option for occlusive atherosclerotic lesions in IC and CLI and is the evolving preferred strategy in CLI and perhaps IC with long-segment occlusions.

Successful Endovascular Treatment of a Hemodialysis Graft Pseudoaneurysm by Covered Stent and Direct Percutaneous Thrombin Injection

Vascular access for hemodialysis remains a challenge for nephrologists, vascular surgeons, and interventional radiologists alike. Arteriovenous fistula and synthetic grafts remain the access of choice for long‐term hemodialysis; however, they are subject to complications from infection and repeated needle cannulation. Pseudoaneurysms are an increasingly recognized adverse event. At present, there are many minimally invasive methods to repair these wall defects. We present a graft pseudoaneurysm, which required a combination of endovascular stent graft placement and percutaneous thrombin injection for successful occlusion.

Below knee angioplasty in elderly patients: Predictors of major adverse clinical outcomes

AIM To determine predictors of clinical outcome following percutaneous transluminal angioplasty (PTA) in elderly patients with below knee atherosclerotic lesions causing intermittent claudication (IC) or critical limb ischaemia (CLI). MATERIALS AND METHODS Over 7.5 years, 76 patients (CLI 72%, n = 55) underwent below knee PTA. The composite end-point of interest was major adverse clinical outcome (MACO) of the treated limb at follow-up which was defined as clinical failure, need for subsequent endovascular or surgical revascularization or amputation. Actuarial freedom from MACO was assessed using Kaplan-Meier curves and multivariable Cox proportional hazards regression. RESULTS IC was improved in 95% at mean 3.4 years (range 0.5-108 months). Successful limb salvage and ulcer healing were seen in 73% with CLI. Most failures were in the CLI group (27% CLI vs. 5% IC), with an amputation rate of 16% for CLI vs. 5% for IC and persistent ulceration in 24% of CLI. Significant independent predictors of MACO were ulceration (hazard ratio 4.02, 95% CI = 1.55-10.38) and family history of atherosclerosis (hazard ratio 2.53, 95% CI = 1.1-5.92). CONCLUSION Primary below knee PTA is a feasible therapeutic option in this elderly population. Limb ulceration and family history of atherosclerosis may be independent predictors of adverse outcome.

Cocaine-Associated Lower Limb Ischemia

Cocaine-associated thrombosis has been reported in the literature with reports of vascular injuries to cardiac, pulmonary, intestinal, placental, and musculoskeletal vessels; however, injury of the pedal vessels is rare. We report on a 31-year-old man who presented 2 months following a cocaine binge with limb-threatening ischemia without an otherwise identifiable embolic source. Angiography confirmed extensive occlusive disease of the tibioperoneal vessels. The patient improved following therapy with heparin and a prostacyclin analogue. Cocaine-induced thrombosis should be considered in patients presenting with acute arterial insufficiency in the lower limb without any other identifiable cause.

Do AshSplit Haemodialysis Catheters Provide Better Flow Rates in the Long Term

Background. Recently, interventional radiologists have adopted an increasingly prominent role in the placement and management of hemodialysis catheters, as well as in the research and development of new and better catheters. The purpose of this study was to evaluate the viability and hemodialysis efficiency of the AshSplit catheter and the Permcath catheter. Methods. 204 consecutive patients requiring radiological insertion of hemodialysis catheters were followed, retrospectively, over a 42-month period. Both hemodialysis catheters were placed using a combination of ultrasonic and fluoroscopic guidance and tunneled appropriately. Information collected included catheter insertion sites, insertion complications, catheter duration, and final outcome. Results. Over the study period of two years, 269 catheters were placed into 204 patients with end stage renal failure. Patients received either an AshSplit (101 patients, 127 catheters) or a Permcath (103 patients, 142 catheters). Vascular access route of choice was the right internal jugular vein (67% AshSplit, 71% Permcath). Insertion complications occurred in 18 patients overall (6.6%), with only 1 requiring further intervention (hemopneumothorax). Flow rates averaged 259 mls/min for AshSplits and 248 mls/min for Permcaths (p < 0.001). Follow-up of catheter viability for 42 months yielded a mean AshSplit catheter duration of 246 days (range 6–932) and 239 days (range 1–1,278) for Permcath (p = 0.46). Reasons for catheter failure and elective catheter removal were similar in both groups; however, Permcaths required significantly more thrombolysis than AshSplits, p < 0.001. Conclusion. The AshSplit provides significantly better flow rates and less thrombolysis compared to the Permcath, with similar catheter dwell times.

A prospective comparison of the performance and survival of two different tunnelled haemodialysis catheters: SplitCath® versus DuraMax®

Background Despite their well-recognised shortcomings, haemodialysis catheters (HDCs) remain an important form of haemodialysis access for many patients. There are several HDCs commercially available, each differing considerably in design, which is known to significantly influence performance and survival. We sought to determine which of two tunnelled HDCs, DuraMax® (Angiodynamics, NY, USA) or SplitCath® (MedComp, PA, USA) delivers the best performance, safety and reliability for dialysis patients. Methods Eighty-six patients were prospectively randomised to receive either DuraMax® (DM) or SplitCath® (SC). Outcomes included: (i) mean flow rates (mL/min) averaged over the first 10 weeks of dialysis, and urea reduction ratio (URR); and (ii) long-term catheter survival with appraisal of any events leading to catheter dysfunction and early removal. Results Median flow rates (interquartile range) in the DM and SC groups were 321 (309-343) and 309 (294-322) mL/min, respectively (p = 0.002). URR values for the DM and SC groups were 71 (65-76) and 74 (70-78), respectively, (p = 0.094). There was no significant difference in long-term survival or frequency of incidents that required early HDC removal (9/43 in the DM group, 5/43 patients SC). A slightly higher incidence of HDC dislodgement was noted in the DM group, although this study was not statistically powered to determine its significance. Conclusions We conclude that DM yields slightly higher flow rates in the first 10 weeks of dialysis, and a similar low incidence of complications and long-term survival for both DM and SC HDCs.

Percutaneous antegrade ureteric stent removal using a rigid alligator forceps

To evaluate the safety and efficacy of percutaneous antegrade ureteric stent removal using a rigid alligator forceps. Twenty patients were included in our study. Indications for ureteric stent insertion included stone disease (n = 7), malignancy (n = 8) and transplant anastomotic strictures (n = 5). Stent retrieval was carried out for proximal stent placement/migration in seven patients and encrustation in the remaining 13. Twenty‐two stents were successfully retrieved in 20 patients. There was one technical failure (5%). There were no major complications. We had four minor complications, which included nephrostomy site pain (n = 2), periprocedural sepsis (n = 1) and a small urinoma (n = 1). All patients settled with conservative management. Percutaneous radiologically guided antegrade ureteric stent removal with an alligator forceps is safe and effective, particularly when initial surgical removal has failed.