Evaluation of the redesigned conformable GORE TAG thoracic endoprosthesis for traumatic aortic transection.

OBJECTIVE: To evaluate the safety and effectiveness of the conformable GORE TAG thoracic endoprosthesis (CTAG) device (W. L. Gore and Associates, Flagstaff, Ariz) for the endovascular repair of traumatic aortic transections. METHODS: A prospective, nonrandomized, multicenter trial was conducted at 21 sites. Primary safety end points included 30-day all-cause mortality. The effectiveness end point was freedom from a major device event requiring reintervention through 1-month follow-up. RESULTS: Fifty-one subjects were enrolled between December 2009 and January 2011 with polytraumatic injuries and a mean Injury Severity Score of 32 ± 14. The proximal mean intimal aortic diameter measured 24 mm, while the mean distal intimal diameter was 22 mm. A total of 57 CTAG devices were implanted (mean, 1.1/subject; range, 1-2) with a mean patient age of 44 years (range, 21-87) and a male-to-female ratio of 2:1. Technical success was 100% with an operative mortality of 0%. Femoral access was utilized in 96% of patients. The mean procedure time and blood loss was 105 minutes and 148 mL, respectively. All subjects required admission to an intensive care unit with a mean hospital stay of 14.6 days. Adjuvant techniques (ie, lumbar drains and induced hypertension) to prevent paraplegia were used in only 7.8% of patients. No patient developed paraplegia despite 63% having complete or partial left subclavian artery coverage and only 9% of those receiving left subclavian artery revascularization. In addition, there were no device compressions or major device events reported. Overall mortality at 30 days was 7.8%, and all were adjudicated by the clinical events committee as not being device or procedure related. Serious adverse events occurred in 39.2% of patients through 30 days. To date, there have been no conversions to open repair. Two site-reported endoleaks were detected during the mean follow-up of 4.2 months, which did not require reintervention. CONCLUSIONS: The CTAG device was demonstrated to be a safe and effective treatment for traumatic aortic transection based on 30-day outcomes. There were no device-related serious adverse events.

Current status of endovascular aneurysm repair: 20 years of learning.

Parodi first introduced endovascular aneurysm repair (EVAR) in 1991 and since that time it has been shown to have a lower 30-day morbididty and mortality compared to open surgery. Anatomic constraints governed by the need for adequate access vessels, and sufficient proximal and distal landing zones, as well as the need for long-term surveillance, have been the main limitations of this technology. Anatomic factors were initially estimated to exclude 40% of patients with abdominal aortic aneurysm (AAA). The rapid extension of EVAR technology has been complimented by improved access to both high-quality imaging modalities and a variety of endografts. These developments have led EVAR to become a more practical alternative for patients with ruptured AAA. Early data in this setting is encouraging with even more profound reductions in morbidity and mortality than seen in the elective repair.

Spontaneous splanchnic dissection: application and timing of therapeutic options.

BACKGROUND: Spontaneous splanchnic dissection (SSD) occurs infrequently and has a poorly defined natural history. Few studies address the application, timing, and consequences of therapeutic options. Our goal was to apply conservative (non-operative) management in the care of each patient, reserving interventions for specific indications that may be predictive of adverse outcomes. METHODS: Between 2003 and 2008, 10 consecutive patients (mean age 54.7-years-old, 70.0% male) presented with 11 SSDs involving either the celiac artery (n = 6), superior mesenteric artery (n = 3), or both (n = 1). Each patient had acute, spontaneous onset of persistent abdominal pain and was diagnosed with SSD following multidetector row computed tomographic angiography (CTA). Non-operative management (anticoagulation, anti-impulse therapy, analgesics, and serial CTA examinations) was initially used in 9 patients. Endovascular (n = 2) or operative (n = 2) intervention was performed either immediately (n = 1) or following failed medical management (n = 3) in 4 patients for specific indications that included persistent symptoms (n = 3), expansion of false lumen (n = 3), and/or radiologic malperfusion (n = 3). RESULTS: All patients were asymptomatic after successful non-operative management or following intervention. No morbidity occurred. Upon complete follow-up (mean 13.4 months, range, 2 to 36 months), all patients remained asymptomatic. Preservation of distal perfusion with either thrombosis or ongoing regression of false lumen was achieved in 5 patients who received only non-operative management and in 4 patients following intervention. A stable chronic dissection was present in 1 patient who had only non-operative management. CONCLUSION: Successful outcomes following SSD may be achieved with either non-operative therapy alone or intervention if persistent symptoms, expansion of false lumen, and/or malperfusion occur. The unpredictable response of the false lumen to conservative management mandates close, long-term follow-up. Endovascular and operative interventions produced similar outcomes in a small number of patients with limited follow-up. Although SSD is currently perceived as rare, the increasing use of CTA may prove that the true incidence has been underestimated.

Use of a percutaneous septal occlusion device to exclude a juxta-renal pseudoaneurysm of the abdominal aorta.

Abdominal aortic pseudoaneurysm is an uncommon, but challenging condition. The most common etiologies are either trauma or iatrogenic repair via open surgery, endovascular aortic cuff, and exclusion via placement of coils has been described. We describe a case of a juxta-renal aortic pseudoaneurysm following aorto-bi-iliac bypass grafting that was successfully excluded by endovascular placement of a percutaneous septal occlusion device.

Endovascular exclusion of mycotic aortic aneurysm.

The presence of prohibitive risk may preclude usual surgical management. Such was the case for a critically ill, 60-year-old woman who presented with concomitant, life-threatening conditions. The patient presented with acute central cord syndrome and lower-extremity paraplegia after completing a 6-week course of intravenous antibiotics for methicillin-sensitive Staphylococcus aureus bacteremia and osteomyelitis of the thoracic spine. Radiologic examination revealed bony destruction of thoracic vertebrae T4 through T6, impingement on the spinal cord and canal by an inflammatory mass, and a separate 2.5-cm mycotic aneurysm of the infrarenal aorta. The clinical and radiologic findings warranted immediate decompression and stabilization of the spinal cord, aneurysmectomy, and vascular reconstruction. However, the severely debilitated patient could not tolerate 2 simultaneous open procedures. She underwent emergent endovascular exclusion of the mycotic aneurysm with a stent-graft, followed immediately by laminectomy and stabilization of the thoracic spine. Intraoperative microbiology specimens showed no growth. The patient was maintained on prophylactic antibiotic therapy for 6 months. Fourteen months postoperatively, her neurologic function was near full recovery, and neither surveillance blood cultures nor radiologic examinations showed a recurrence of infection or aneurysm. Although the long-term outcome of endovascular stent-grafts in the treatment of culture-negative mycotic aneurysms is unknown, the use of these grafts in severely debilitated patients can reduce operative risk and enable recovery in the short term.

Arteriopathy in the high-performance athlete.

Pain occurs frequently in high-performance athletes and is most often due to musculoskeletal injury or strain. However, athletes who participate in sports that require highly frequent, repetitive limb motion can also experience pain from an underlying arteriopathy, which causes exercise-induced ischemia. We reviewed the clinical records and follow-up care of 3 high-performance athletes (mean age, 29.3 yr; range, 16-47 yr) who were admitted consecutively to our institution from January 2002 through May 2003, each with a diagnosis of limb ischemia due to arteriopathy. The study group comprised 3 males: 2 active in competitive baseball (ages, 16 and 19 yr) and a cyclist (age, 47 yr). Provocative testing and radiologic evaluation established the diagnoses. Treatment goals included targeted resection of compressive structures, arterial reconstruction to eliminate stenosis and possible emboli, and improvement of distal perfusion. Our successful reconstructive techniques included thoracic outlet decompression and interpositional bypass of the subclavian artery in the 16-year-old patient, pectoralis muscle and tendon decompression to relieve compression of the axillary artery in the 19-year-old, and patch angioplasty for endofibrosis affecting the external iliac artery in the 47-year-old. Each patient was asymptomatic on follow-up and had resumed participation in competitive athletics. The recognition and anatomic definition of an arteriopathy that produces exercise-induced ischemia enables the application of precise therapy that can produce a symptom-free outcome and the ability to resume competitive athletics.

Does post-stenotic dilatation enhance collateral flow?

Our goal was to investigate whether post-stenotic dilatation (PSD) enhances collateral blood flow. In vitro experiments and computer modeling analysis were used to study the flow through stenotic segments and through collateral channels in the presence and absence of PSD. Pulsatile blood flow was provided by a left heart simulator primed with glycerol or normal saline. Pressure gradients across the stenosis were measured at different "cardiac" outputs. Computer models were constructed to simulate the experiments. Flow patterns and pressure drop across the stenosis were determined for a steady flow of 3 L/min. We observed that PSD was associated with a larger pressure drop across the stenosis than the absence of PSD when the flow was occurring through the stenosis only. There was, however, no difference in the pressure drop between the two geometries when the flow was occurring through both the stenotic orifice and the collateral channels when saline solution was used, but a small pressure difference prevailed for glycerol. At all different geometries there was considerable turbulence at PSD, and PSD geometry was found to be either at a disadvantage or at no advantage when compared to the tapered geometry for the total flow past the stenosis. The PSD geometry, however, enhanced the flow through the collateral while the flow through the orifice decreased concomitantly, resulting in no net increase in the total flow. This was true for any proportion of the total flow going through the collateral channels. For the total flow past the stenosis, PSD does not offer a benefit over tapered geometry.

Prevention of contrast-induced nephropathy with sodium bicarbonate: a randomized controlled trial.

CONTEXT: Contrast-induced nephropathy remains a common complication of radiographic procedures. Pretreatment with sodium bicarbonate is more protective than sodium chloride in animal models of acute ischemic renal failure. Acute renal failure from both ischemia and contrast are postulated to occur from free-radical injury. However, no studies in humans or animals have evaluated the efficacy of sodium bicarbonate for prophylaxis against contrast-induced nephropathy. OBJECTIVE: To examine the efficacy of sodium bicarbonate compared with sodium chloride for preventive hydration before and after radiographic contrast. DESIGN, SETTING, AND PATIENTS: A prospective, single-center, randomized trial conducted from September 16, 2002, to June 17, 2003, of 119 patients with stable serum creatinine levels of at least 1.1 mg/dL (> or =97.2 micromol/L) who were randomized to receive a 154-mEq/L infusion of either sodium chloride (n = 59) or sodium bicarbonate (n = 60) before and after iopamidol administration (370 mg iodine/mL). Serum creatinine levels were measured at baseline and 1 and 2 days after contrast. INTERVENTIONS: Patients received 154 mEq/L of either sodium chloride or sodium bicarbonate, as a bolus of 3 mL/kg per hour for 1 hour before iopamidol contrast, followed by an infusion of 1 mL/kg per hour for 6 hours after the procedure. MAIN OUTCOME MEASURE: Contrast-induced nephropathy, defined as an increase of 25% or more in serum creatinine within 2 days of contrast. RESULTS: There were no significant group differences in age, sex, incidence of diabetes mellitus, ethnicity, or contrast volume. Baseline serum creatinine was slightly higher but not statistically different in patients receiving sodium bicarbonate treatment (mean [SD], 1.71 [0.42] mg/dL [151.2 [37.1] micromol/L] for sodium chloride and 1.89 [0.69] mg/dL [167.1 [61.0] micromol/L] for sodium bicarbonate; P =.09). The primary end point of contrast-induced nephropathy occurred in 8 patients (13.6%) infused with sodium chloride but in only 1 (1.7%) of those receiving sodium bicarbonate (mean difference, 11.9%; 95% confidence interval [CI], 2.6%-21.2%; P =.02). A follow-up registry of 191 consecutive patients receiving prophylactic sodium bicarbonate and meeting the same inclusion criteria as the study resulted in 3 cases of contrast-induced nephropathy (1.6%; 95% CI, 0%-3.4%). CONCLUSION: Hydration with sodium bicarbonate before contrast exposure is more effective than hydration with sodium chloride for prophylaxis of contrast-induced renal failure.