Mark A. Patterson

Early outcomes of thoracic endovascular stent-graft repair for acute complicated type B dissection using the Gore TAG endoprosthesis.

We assessed the technical success and early outcome of thoracic endovascular aortic repair (TEVAR) for complicated acute type B thoracic aortic dissection treated at a single institution using a commercially available device. All patients with symptomatic complicated acute type B thoracic aortic dissection treated with TEVAR since Food and Drug Administration approval of the Gore (Flagstaff, AZ) TAG endoprosthesis were identified from a prospectively maintained vascular registry. Clinical indications, operative technique, perioperative complications, follow-up imaging, and mortality were analyzed. Between March 2005 and November 2007, 127 TEVARs using the TAG endoprosthesis were performed, of which 15 (11.8%) were for complicated acute type B thoracic aortic dissection. Indications for repair were malperfusion (53%), persistent pain (27%), and primary aortic failure (33%). Technical feasibility and success with deployment proximal to the entry tear was 93.3%, requiring at least partial coverage of the left subclavian artery in seven (46.7%). Adjunctive procedures required at the time of TEVAR included renal stent (n = 2), iliac stent (n = 3), and access-artery open repair (n = 2). Twelve patients (80%) had immediate resolution of the malperfusion deficit. Major perioperative complications included paraplegia (13.3%), renal failure requiring hemodialysis (13.3%), and stroke (6.7%). Perioperative mortality was 13.3%, occurring in one patient presenting with rupture and one with profound heart failure on admission. For complicated acute type B thoracic aortic dissection, TEVAR using commercially available stent grafts showed high technical success, excellent results at resolving malperfusion, and acceptably low complications and perioperative mortality.

Protocol Implementation of Selective PostOperative Lumbar Spinal Drainage after Thoracic Aortic Endograft

BACKGROUND Spinal cord ischemia (SCI) remains a significant concern in patients undergoing endovascular repair involving the thoracic aorta (thoracic endovascular aortic repair [TEVAR]). Perioperative lumbar spinal drainage has been widely practiced for open repair, but there is no consensus treatment protocol using lumbar drainage for SCI associated with TEVAR. This study analyzes the efficacy of an institutional protocol using selective lumbar drainage reserved for patients experiencing SCI following TEVAR. METHODS A prospectively maintained registry was reviewed to identify all patients who underwent TEVAR from January 2000 through June 2010. Preoperative characteristics, intraoperative details, and outcomes, including neurologic deficit and mortality at 30 days and 1 year were determined based on reporting standards. Patients developing symptoms of SCI in the postoperative setting were compared with those without neurologic symptoms. SCI patients who received selective lumbar drainage were grouped based on resolution of neurologic function, with risk factors and outcomes of these subgroups analyzed with χ(2), t test, logistic regression, and analysis of variance (ANOVA). RESULTS Two hundred seventy-eight TEVARs were performed on 251 patients. Twelve patients accounting for 12 TEVARs were excluded from analysis: 5 patients experienced SCI preoperatively, 4 patients were drained preoperatively, 2 expired intraoperatively, and 1 procedure was aborted. Of the remaining 266 procedures in 239 patients, 16 (6.0%) developed SCI within the 30-day postoperative period. Risk factors for SCI reaching statistical significance included length of aortic coverage (P = .036), existence of infrarenal aortic pathology (P = .026), and history of stroke (P = .043). Stent graft coverage of the left subclavian artery origin was required in 28.9% (n = 77) and was not associated with SCI (P = .52). Ten of 16 post-TEVAR SCI patients received selective postoperative lumbar drains and were categorized based on resolution of symptoms into complete resolution (n = 3; 30%), partial resolution (n = 4; 40%), and no resolution (n = 3; 30%). No patient characteristics or risk factors reached significance in comparison of lumbar drained patients and nondrained patients. All seven drained patients without complete resolution of SCI died within the first year after surgery, while all three of the complete responders survived (P = .017). In patients with SCI, increased all-cause mortality was observed at 1 year (56.3% vs 20.4%; P = .003). CONCLUSIONS A protocol utilizing selective postoperative lumbar spinal drainage can be used safely for patients developing SCI after TEVAR with acceptably low permanent neurologic deficit, although overall survival of patients experiencing SCI after TEVAR is diminished relative to non-SCI patients.

Prospective implementation of an algorithm for bedside intravascular ultrasound-guided filter placement in critically ill patients

BACKGROUND Although contrast venography is the standard imaging method for inferior vena cava (IVC) filter insertion, intravascular ultrasound (IVUS) imaging is a safe and effective option that allows for bedside filter placement and is especially advantageous for immobilized critically ill patients by limiting resource use, risk of transportation, and cost. This study reviewed the effectiveness of a prospectively implemented algorithm for IVUS-guided IVC filter placement in this high-risk population. METHODS Current evidence-based guidelines were used to create a clinical decision algorithm for IVUS-guided IVC filter placement in critically ill patients. After a defined lead-in phase to allow dissemination of techniques, the algorithm was prospectively implemented on January 1, 2008. Data were collected for 1 year using accepted reporting standards and a quality assurance review performed based on intent-to-treat at 6, 12, and 18 months. RESULTS As defined in the prospectively implemented algorithm, 109 patients met criteria for IVUS-directed bedside IVC filter placement. Technical feasibility was 98.1%. Only 2 patients had inadequate IVUS visualization for bedside filter placement and required subsequent placement in the endovascular suite. Technical success, defined as proper deployment in an infrarenal position, was achieved in 104 of the remaining 107 patients (97.2%). The filter was permanent in 21 (19.6%) and retrievable in 86 (80.3%). The single-puncture technique was used in 101 (94.4%), with additional dual access required in 6 (5.6%). Periprocedural complications were rare but included malpositioning requiring retrieval and repositioning in three patients, filter tilt >/=15 degrees in two, and arteriovenous fistula in one. The 30-day mortality rate for the bedside group was 5.5%, with no filter-related deaths. CONCLUSIONS Successful placement of IVC filters using IVUS-guided imaging at the bedside in critically ill patients can be established through an evidence-based prospectively implemented algorithm, thereby limiting the need for transport in this high-risk population.

Long-term single institution comparison of endovascular aneurysm repair and open aortic aneurysm repair

INTRODUCTION Since the development of endovascular aneurysm repair (EVAR), there remains concerns regarding its durability, need for secondary procedures, and associated long-term morbidity. We compared these two approaches to evaluate secondary interventions and their respective long-term durability. METHODS All patients who had undergone endovascular and open abdominal aortic aneurysm (AAA) repair were identified from a prospectively maintained registry. Health system charts, medical communication, and national death indexes were reviewed. Secondary interventions were classified as vascular (aortic graft or remote) and nonvascular (incisional or gastrointestinal). RESULTS Between July 1985 and September 2009, 1908 patients underwent 1986 AAA repair procedures (EVAR = 1066; open = 920). Patients were followed up to 290 months (mean 27.6 ± 35.9) and identified with 427 surgical encounters (EVAR 233% to 21.9%; open 194% to 21.1%). Most encounters (338% to 74.6%) were related to vascular disease: 178 (EVAR = 131; open = 47) related to the aortic graft; 160 (EVAR = 93; open = 67) were related to nonaortic vascular disease. The remaining 89 surgical encounters included incisional hernias, small bowel obstruction, intra-abdominal abscesses, and wound dehiscence requiring operation. Of these 89 encounters (EVAR = 9; open = 80), 44 patients required surgical intervention and 36 required hospitalization without surgical procedure. Over the period of 100 months, the all-cause mortality rate was 25.2% after EVAR and 39.1% after open repair. One-year survival was 88.0% (SE 0.01) and 85.0% (SE 0.01), while 5-year survival was 58.0% (SE 0.02) and 53.0% (SE 0.02) for EVAR and open repair, respectively (log-rank P value < .0164). Seven-year survival was 46% (SE 0.03) for EVAR and 36% (SE 0.03) for open AAA repair. CONCLUSION EVAR requires more late secondary vascular interventions than open AAA repair, but patients who undergo open repair have more nonvascular long-term morbidity. Long-term survival is better after EVAR compared to open repair in this selected patient group.

Outcomes after celiac artery coverage during thoracic endovascular aortic aneurysm repair

OBJECTIVE Coverage of celiac artery (CA) during thoracic endovascular aortic aneurysm repair (TEVAR) has been performed to extend the distal seal zone for which preliminary results and short-term follow-up have been reported. We aim to show the outcomes up to 81 months after CA coverage during TEVAR. METHODS Patients undergoing TEVAR with coverage of the CA origin from 2005 to 2013 were retrospectively analyzed. Points of analysis include indications for covering the CA, demonstration of collateral circulation between the CA and superior mesenteric artery (SMA), anatomic features of the distal landing zone, rate of reintervention, technical success, presence of clinical ischemic symptoms after the procedure, and mortality. RESULTS During the 9-year period, 366 patients underwent TEVAR, 18 (5%) of whom had CA coverage. Eleven (61%) had TEVAR with CA coverage due to a thoracic aneurysm, three (17%) had thoracic aortic dissection related to aneurysm, and four (22%) had previous TEVAR with a type Ib endoleak (EL) requiring distal coverage. Mesenteric angiography in preparation for TEVAR with CA coverage diagnosed a critical SMA stenosis in one patient that was treated with stenting before the index procedure. At the conclusion of the indicated procedure, two patients (11%) had a type Ia EL and two patients (11%) had a type Ib EL. Three of the type I ELs required reintervention. Two patients (11%) had a type II EL, both of which were managed with observation and resolved. Reintervention was required in 27% of patients. Postoperative complications included visceral ischemia in 2 (11%), weight loss in 1 (5%), spinal cord ischemia in 2 (11%), a cerebrovascular event in 1 (6%), and death in 1 (6%). The mean follow-up period was 38 months (range, 0.5-81 months). CONCLUSIONS This analysis of outcomes up to 81 months supports the suitability of covering the CA in selected patients for extending the distal landing zone to the visceral aortic level above the SMA or when alternative branch vessel treatment is unavailable. Preoperative angiographic evaluation of the mesenteric collaterals and early postoperative surveillance may limit postoperative complications. Once the CA is covered, new symptoms do not develop unless the SMA is compromised.

Evaluating Outcomes of Endoleak Discrepancies Between Computed Tomography Scan and Ultrasound Imaging After Endovascular Abdominal Aneurysm Repair

BACKGROUND Endovascular repair for abdominal aortic aneurysm (EVAR) requires regular surveillance to ensure long-term durability. To understand the clinical consequence of discrepancies in endoleak detection between computed tomographic angiography (CTA) and duplex ultrasound (DUS) imaging, this study evaluated patients who underwent EVAR. The aim of the present study was to determine whether these discrepancies affected the long-term outcome after EVAR, and whether DUS predicted the need for re-intervention on the basis of other markers despite missing endoleaks. METHODS A review of the prospectively maintained database was completed to capture all EVAR procedures performed between October 1999 and June 2009. Patients were routinely evaluated with computed tomography (CT) and DUS imaging within 30 days after the procedure and intermittently at 6-12 month intervals after treatment. DUS imaging was evaluated with attention toward maximum aneurysm diameter, presence of an endoleak, and compared with findings on simultaneous contrast CT imaging. RESULTS The database and patient records identified 1,062 EVARs in 992 patients who underwent 3,120 imaging encounters through the surveillance protocol. Of these 3,120 encounters, 610 had both CT scan and ultrasound at the same visit. Contrast material was not used in 49 CT scans, leaving 561 encounters for comparing contrast CT imaging with DUS results. CT and DUS detection of endoleaks correlated in 442 encounters (78.8%). Discrepancies occurred in 119 encounters (21.2%) as follows: CT scan only endoleak in 17.8% (N = 100; type I = 6, type II = 91, and type III = 3) and DUS only endoleak in 3.4% (N = 19; type II = 19) encounters. Of these 119 encounters, 99 (17.6%) did not require secondary interventions. Eventually, 15 patients required intervention after 20 discrepancy encounters (3.6%): 11 patients continued with the surveillance protocol through CT or DUS imaging, whereas four were observed by CT imaging only. Considering these 11 patients, DUS eventually detected an endoleak on subsequent visits in five patients, DUS identified an increase in aneurysm diameter in four patients, and DUS never identified the type II endoleaks in two patients. When the endoleak raised concern or the aneurysm enlarged, we undertook 19 secondary interventions in these 15 patients: vessel embolization (N = 8), iliac extenders (N = 5), graft relining (N = 3), graft explants (N = 2), and proximal cuff (N = 1). Although three ruptures occurred in our entire treatment experience, no ruptures occurred in patients who maintained the prescribed surveillance protocol. CONCLUSION Surveillance after EVAR is necessary because secondary interventions are sometimes required. Although DUS has lower sensitivity in detecting endoleaks, comparison with CT findings can identify the appropriate patients for DUS surveillance only. Even considering the discrepancies between CT imaging and DUS, repeated DUS surveillance might identify an unstable aneurysm that requires further intervention. Although DUS has not been established as an exclusive surveillance tool, it can be used to effectively monitor patients after EVAR with reduced need for CT imaging.

Effect of lipid-modifying drug therapy on survival after abdominal aortic aneurysm repair.

BACKGROUND Lipid-modifying drug therapy (LMDT) is recommended in all patients having coronary or noncoronary atherosclerotic disease. However, the effect of LMDT after abdominal aortic aneurysm (AAA) repair, especially in the absence of other atherosclerotic manifestations, is unclear. We examined the distribution of prevalence of LMDT among patients undergoing AAA repair and its effect on survival in the presence and absence of other atherosclerotic diseases. METHODS We identified patients treated at University of Alabama at Birmingham between 1985 and 2010 who had a prior AAA repair. Information was collected from health system medical charts, medical communication, and national death indices. We assessed the predictors of prevalence of LMDT by univariate analysis using t-test for continuous and χ(2) test for categorical variables, and then performed multivariate logistic regression. The survival was determined using Kaplan-Meier plots, and adjusted hazard ratios were calculated using Cox proportion regression. RESULTS A total of 2063 patients underwent AAA repair procedure. Of these, 9% were African-American, and 20% were female. Thirty-five percent received LMDT, and 32% died during the follow-up period of up to 240 months. Significant predictors for being on LMDT included white race (odds ratio [OR], 1.6; 95% confidence interval [CI], 1.1-2.2), presence of other atherosclerotic disease or diabetes (OR, 2.4; 95% CI, 1.9-3.0), hypertension (OR, 4.0; 95% CI, 3.1-5.2), smoking (OR, 1.6; 95% CI, 1.2-2.1), and endovascular AAA repair (OR, 1.9; 95% CI, 1.5-2.3). LMDT was associated with improved survival (hazard ratio, 0.6; 95% CI, 0.5-0.8) after controlling for traditional risk factors, diabetes, and other atherosclerotic diseases. CONCLUSIONS LMDT after AAA is associated with an increased survival compared with patients who were not using drug therapy for dyslipidemia. Aggressive management of dyslipidemia should be considered in all patients undergoing AAA repair irrespective of other atherosclerotic disease status and risk factor profile.

Should Endovascular Repair Be Used for Small Abdominal Aortic Aneurysms

The outcomes of endovascular repair for small abdominal aortic aneurysm (4.0-4.9 cm) is reported. All patients undergoing endovascular abdominal aortic aneurysm repair between 2000 and 2006 with maximal diameter 4.0 to 4.9 cm form the small aneurysm study cohort. Data were analyzed retrospectively and life-table methods were used. Of 743 endovascular repairs, 132 (17.8%) were performed for small abdominal aortic aneurysm. Perioperative complication rate was 9.1%. Freedom from aneurysm expansion was 96% at 1 year, 86% at 3 years, and 77% at 5 years. Overall survival was 98%, 93%, and 84% at 1, 3, and 5 years, respectively. Perioperative 30-day mortality was 0.8% with an aneurysm-related mortality of 1.5% at 5 years. There were no deaths from delayed aneurysm rupture. Endovascular repair of small abdominal aortic aneurysm is associated with low perioperative morbidity and mortality compared with published results for open repair, and treatment threshold can be reduced to 4 cm in selected patients.

Analysis of emergency vascular surgery consults within a tertiary health care system

OBJECTIVE Patients with vascular disease often have multisystem atherosclerosis and multiple comorbidities requiring comprehensive interdisciplinary specialty care. Consultation is a critical component of a tertiary vascular surgery practice, but analysis of this service is under-reported in the literature. After-hours inpatient consultations and interhospital transfers are associated with urgent patient care. METHODS A retrospective analysis of vascular surgery consultations was carried out from January 1, 2013, to December 31, 2013. Consultations included inpatient services, the emergency department, surgical and medical intensive care unit, and interhospital transfers. Data analysis included number of consults, time of consultation (during hours, 0700-1859; after hours, 1900-0659), referring service, nature, and outcome of consultation. Consultations were then classified as urgent if vascular surgical intervention was required as an intraoperative consultation, within 24 hours, or during the same hospitalization. Patients without a same-hospital vascular surgical intervention were classified as nonurgent. RESULTS During a 1-year period, 823 independent consult requests of 749 patients were analyzed. It was found that 57.8% of after-hours consults resulted in urgent patient care (P = .003); 29.7% of medicine, 33.3% of medical intensive care unit, 41.9% of trauma surgery, and 60% of emergency department after-hours consultations were urgent; 73% of surgery and 79.2% of interhospital after-hours consults required urgent vascular surgical intervention. Extremity ischemia, aortic disease, and iatrogenic consults accounted for 44.8%, 20.4%, and 11.1% of after-hours consults, with 57.9%, 56.4%, and 70% requiring urgent vascular surgical intervention, respectively. CONCLUSIONS After-hours consultations are not always associated with an urgent vascular surgical intervention. Nonurgent after-hours consultations are requested more frequently from some services and may present an opportunity for education that could improve workflow of the vascular workforce.

Impact of Glucose Control and Regimen on Limb Salvage in Patients Undergoing Vascular Intervention

to 39 of 60 (65%) in the usual group (P < .001). The mean hospital length of stay in patients with BTAI at the unusual locations was 8.5 days compared with 20.3 days in the usual location group (P < .004). Mortality occurred in 5 of 14 (36%) in the unusual location group compared with 5 of 60 (8%) in the usual location group. No deaths were related to the BTAI itself in the unusual location group. Conclusions: BTAIs at unusual locations are associated with several characteristics. They are more frequently associated with thoracic spine injuries, are more common in women, tend to be lower grade, are less likely to require intervention, and appear to have a higher mortality due to other traumatic injuries.