Joseph J. Naoum

Impact of runoff on superficial femoral artery endoluminal interventions for rest pain and tissue loss

BACKGROUND While aggressive endoluminal therapy for superficial femoral artery (SFA) occlusive disease is commonplace, the implications of runoff on long-term outcomes of these interventions in patients with rest pain and tissue loss is unclear. Runoff is known to negatively effect graft patency. The aim of this study is to examine the impact of distal runoff on long-term outcomes of SFA interventions for critical ischemia. METHODS A prospective database of patients undergoing endovascular treatment of the SFA between 1986 and 2007 was queried. Patients with Rutherford symptom classification 4, 5, and 6 were selected. Patients with concomitant tibial interventions were excluded. Pre-operative angiograms were reviewed in all cases to assess distal popliteal and tibial runoff and were scored according to modified Society of Vascular Surgery criteria for both vessels such that a higher score implies worse runoff (minimum 1 and maximum 19). Three runoff score groups were identified: <5 (good), 5-10 (compromised), and >10 (poor). Kaplan-Meier survival analyses were performed to assess time-dependent outcomes. Multivariate and factor analyses were performed. RESULTS Three hundred six limbs in 241 patients (57% male, mean age 68 years) underwent endovascular treatment for critical ischemia (44% rest pain and 56% tissue loss.) Technical success was 96% with 61% SFA undergoing angioplasty, 37% SFA primary stenting and 2% SFA an atherectomy. Overall mortality was 1% and overall morbidity was 16% at 90 days after the procedure. At 5 years, vessels with compromised and poor runoff had significantly worse cumulative patency (82 +/- 9%, 56 +/- 4%, and 52 +/- 7% for good, compromised, and poor runoffs, respectively, mean +/- standard error of the mean [SEM]). Freedom from recurrent symptoms (65 +/- 8%, 39 +/- 9%, and 18 +/- 9% for good, compromised, and poor runoffs, respectively) and limb salvage (65 +/- 5%, 41 +/- 4%, and 20 +/- 6% for Good, Compromised, and Poor runoffs, respectively) were incrementally curtailed by worsening runoff with significant decreases as runoff category deteriorated. CONCLUSIONS In patients presenting with rest pain and tissue loss who are treated with SFA percutaneous interventions, patency is negatively affected by compromised and poor runoffs in keeping with the bypass literature. More importantly, freedom from recurrent symptoms and limb salvage are incrementally curtailed as runoff scores worsen. These findings are consistent with the bypass literature.

The long-term outcomes of percutaneous therapy for renal artery fibromuscular dysplasia

BACKGROUND Percutaneous intervention for symptomatic renal artery fibromuscular dysplasia (FMD) has replaced surgical therapy as first-line treatment. This study evaluates the factors that impact long-term anatomic and functional outcomes of endovascular therapy for symptomatic renal artery FMD. METHODS Records of patients who underwent renal artery angioplasty for FMD between January 1990 and December 2007 were retrospectively analyzed. Indication for intervention was poorly controlled hypertension (diastolic blood pressure >90 mm Hg or systolic blood pressure >140 mm Hg, or both, taking >2 antihypertensive medications). Twenty-nine women (average age, 45 years [range, 18-80]; 86% with a history of hypertension <8 years) underwent 38 attempted interventions. Sixty-six percent of contralateral kidneys were normal (31% had a </=60% stenosis), 13% had >60% stenosis, and the remainder were nonfunctioning or absent. Creatinine was >1.5 mg/dL in 4%, 24% had hyperlipidemia, 17% had metabolic syndrome, and 4% were considered diabetic. OUTCOMES All interventions were successfully performed. Stent placement was required in 13% for technical failure and flow-limiting dissection. Seventy-three percent of these lesions were in the proximal renal artery, with the remainder in the middle renal artery. Technical success (<30% residual stenosis) was achieved in all vessels. There were no periprocedural or 90-day deaths. The procedurally related complication rate was 8%. Median follow-up was 2 years. All patients were alive at follow-up. Primary and assisted primary patency rates were 66% and 87% at 5 years. Restenosis was considered a 50% reduction in luminal area on angiography during follow-up. The restenosis rate was 28% at 5 years (10 vessels underwent repeat percutaneous intervention). Immediate clinical benefit was seen in hypertension in 72% (improved or cured </=3 months) and was maintained in 73% at 5 years by life-table analysis. Proportional hazard analysis showed the predictors of long-term clinical benefit were duration of hypertension <8 years, creatinine <1.5 mg/dL, ipsilateral kidney size >9 cm, functional status of the contralateral kidney, a fasting blood glucose <110 mg/dL, triglycerides <150 mg/dL, and high-density lipoprotein >50 mg/dL. Neither age <50 years nor statin administration appeared significant. CONCLUSIONS Percutaneous endovascular intervention for clinically symptomatic FMD in the renal arteries is technically successful, safe, and durable. Most patients have immediate clinical benefit, with continued long-term results out to 5 years. It appears that the presence of existing renal pathology and markers of prediabetic state are associated with recurrence of hypertensive symptoms.

Efficacy of covered stent placement for central venous occlusive disease in hemodialysis patients

OBJECTIVES Covered stents have been proposed as an endovascular option for recalcitrant cases of hemodialysis-related central venous occlusive disease (CVOD). This study evaluated the efficacy and durability of covered stents in treating CVOD to preserve a functional dialysis access circuit. METHODS A retrospective review was performed of all patients with clinically significant CVOD who were treated by placement of covered stents from April 2007 to September 2010. Demographics, lesion locations and anatomic characteristics, stent graft, and access patency rates were determined. Complications, reinterventions, and factors influencing their outcomes were examined. RESULTS In 25 patients (56% men; mean age, 57 ± 29 years) with CVOD, covered stents were used in 20 to treat symptomatic venous hypertension or in 5 at the time of access creation to enable functionality. The target lesion was accessed via the dialysis access site or the common femoral vein. The Viabahn endoprosthesis (W. L. Gore and Associates, Flagstaff, Ariz) was used in 24 patients (average size and length, 11 mm × 5 cm) and a 13-mm × 5-cm Fluency covered stent (Bard Peripheral Vascular, Tempe, Ariz) was implanted in 1 patient. Technical success was 100%, and resolution of arm edema occurred after covered stent deployment in symptomatic patients. Two postprocedural cases (8%) of thrombosis occurred, one within 30 days and another at 3 months. Both required percutaneous thrombectomy and percutaneous transluminal angioplasty (PTA). Three additional patients (12%) required PTA due to restenosis in one of the ends of the device. Covered stent primary patency (PP), assisted primary patency (APP), and secondary patency (SP) were 56%, 86%, and 100% at 12 months, respectively. Access patency rates at 12 months were 29%, 85%, and 94% for PP, APP, and SP, respectively, in patients that received a covered stent for access salvage; patency rates were 74%, 85%, and 94% for PP, APP, and SP, respectively, in patients in whom the access was created after the venous outflow restoration. CONCLUSIONS Placement of covered stents for hemodialysis-related CVOD is safe, effective in relieving symptoms, and enabled functionality of new dialysis access circuits. Further prospective and randomized studies are necessary to determine whether covered stents provide superior long-term results to those achieved with PTA and bare metal stents.

Hybrid thoracic endovascular aortic repair: Pushing the envelope

OBJECTIVE Thoracic endovascular aortic repair (TEVAR) can be limited by inadequate proximal and distal landing zones. Debranching or hybrid TEVAR has emerged as an important modality to expand landing zones and facilitate TEVAR. We report a single-center experience with hybrid TEVAR. METHODS We retrospectively reviewed all patients with thoracic aortic disease who received a TEVAR between February 2005 and October 2008. RESULTS Forty-two patients underwent a hybrid procedure (mean age 68 +/- 13 years; 55% men). All patients were denied open surgery due to preoperative comorbidities or low physiologic reserve; 62% had a history of coronary artery disease, 67% had chronic obstructive pulmonary disease, 61% had undergone prior aortic surgery, and 90% had an American Society of Anesthesiology score of 4 and above. The average Society for Vascular Surgery comorbidity score was 12 +/- 2 with a range of 9 to 14. Fifty-five percent of cases were symptomatic on presentation and 83% were done emergently. Seventy-six percent underwent debranching of the aortic arch, 17% of the visceral vessels, and 7% required both. Primary technical success was achieved in all cases and of these, 43% were staged. The 30-day mortality was 5%. Myocardial infarction developed in 5%, respiratory failure in 31%, cerebrovascular accident (stroke or transient ischemic attack) in 19%, and spinal cord ischemia with ensuant paraplegia occurred in 5% of patients. Fifty-eight percent of patients were discharged home, 11% required rehabilitation, and 29% were transferred to a skilled nursing facility. There was a significant association between visceral vessel debranching and both spinal cord ischemia (P = .004) and gastrointestinal complications (P = .005). On the other hand, there was no difference between staged and non-staged hybrid procedures. CONCLUSIONS Hybrid procedures can successfully extend the range of patients suitable for a subsequent TEVAR. These procedures are associated with higher complication rates than isolated infrarenal or thoracic endovascular repair, but given the medical and anatomical complexity of these patients, the current results are quite encouraging.

Endovascular repair of a right-sided descending thoracic aortic aneurysm with a right-sided aortic arch and aberrant left subclavian artery.

Aneurysms involving a right-sided aortic arch and a right-sided descending thoracic aorta with an aberrant origin of the left subclavian artery are rare. We describe the successful surgical repair of this vascular anomaly by the combined use of a left carotid to subclavian artery bypass followed by endovascular stent-graft placement to exclude the aortic aneurysm. We also review the literature associated with this particular anatomic presentation.

The use of abdominal computed tomography scan decreases the frequency of misdiagnosis in cases of suspected appendicitis

BACKGROUND Despite considerable experience the reported frequency of misdiagnosis in patients undergoing appendectomy continues in the range of 20% to 40% in some populations. METHODS We developed a clinical guideline that recommended abdominal computed tomography (CT) for all nonpregnant adults in whom the diagnosis of appendicitis was suspected unless the diagnosis could be ruled out clinically. The records of adult patients that underwent appendectomy from July 1998 through October 2001 were reviewed. The clinical guideline was developed in July 2000. RESULTS There were 194 appendectomies performed, 114 prior to the guideline and 80 after the development of the guideline. The rate of misdiagnosis decreased from 25% to 6% (P <0.05), the rate of CT use increased from 32% to 84% (P <0.05), and the perforation rate remained unchanged. CONCLUSIONS These results support the effectiveness of a clinical guideline that encourage the use of abdominal CT in decreasing the frequency of misdiagnosis in cases of suspected appendicitis.

Surgical management of hemodialysis-related central venous occlusive disease: A treatment algorithm

BACKGROUND Creation and preservation of dialysis access in patients with central venous occlusive disease (CVOD) is a complex problem. The surgical approach and decision-making process remains poorly defined. We evaluated our experience in the surgical management of hemodialysis-related CVOD. Surgical technique, demographics, complications, reinterventions, access function rates, and factors influencing morbidity and mortality were examined. METHODS From January 2006 to May 2010, we performed a total of 1,703 dialysis access-related procedures, 1,021 arteriovenous fistulas (AVFs), 335 arteriovenous grafts (AVGs), and 314 access revisions including endovascular salvage procedures. Seventeen patients (10 women [58%] with a mean age of 44 ± 27 years) with CVOD who were not suitable for peritoneal dialysis or kidney transplant underwent 20 complex vascular access procedures. The indications were need for access creation in 14 cases (70%) and preservation in the remaining 6 (30%). Polytetrafluoroethylene (PTFE) was used for all surgical bypass grafts (BPG). All patients had previously undergone multiple access surgeries and had failed percutaneous interventions for CVOD. RESULTS The surgical planning centered on finding venous outflow for an arteriovenous (AV) access; central venous reconstructions were necessary in 10 (50%) cases (seven [35%] in the thoracic central venous system and three [15%] in infradiaphragmatic vessels) and extracavitary venous BPG in two (10%) cases. Non-venous access options included axillary arterial-arterial chest wall BPG in five (25%) cases and brachial artery to right atrium BPG in three (15%). Technical success was achieved in all cases (100%). Mean follow-up was 14.1 months, both BPG and AV access patency rates were 66% at 6 months and overall average AV access function time was 9.2 months. Of these, 85% of patients were discharged home and following 19 (95%) cases they returned or improved their baseline functional status. One death occurred from multiorgan failure during the 30-day postoperative period. Four additional patients died within 3 years of the procedure secondary to nonsurgical-related comorbidities. CONCLUSION The need for complex vascular accesses will continue as the number of patients with end-stage renal disease increases. CVOD is an access surgical challenge and with this article we propose a decision-making algorithm.

Percutaneous superficial femoral artery interventions for claudication--does runoff matter?

Endoluminal therapy for superficial femoral artery (SFA) occlusive disease for claudication is commonplace, but the implications of tibial vessel runoff on long-term outcomes of these interventions in patients with claudication are unclear. Runoff is known to negatively affect graft patency, but no data are available on the impact of runoff on percutaneous SFA interventions and their implications during follow-up. We examined the impact of distal popliteal and tibial runoff on long-term outcomes of SFA interventions for claudication. A prospective database of patients undergoing endovascular treatment of the SFA between 1986 and 2007 was queried. Patients with Rutherford symptom classifications 1, 2, and 3 were selected; those with concomitant tibial interventions were excluded. Angiograms were reviewed preoperatively in all cases to assess distal popliteal and tibial runoff and scored according to modified Society for Vascular Surgery criteria for both vessels such that a higher score implies worse runoff (minimum 1, maximum 19). Three run-off score groups were identified: <5 (good), 5-10 (compromised), and >10 (poor). Kaplan-Meier survival analyses were performed to assess time-dependent outcomes. Multivariate and factor analyses were performed. There were 481 limbs in 347 patients (70% male, average age 66 years) that underwent endovascular SFA treatment for claudication: 87% had hypertension, 51% had diabetes mellitus, 67% had hyperlipidemia, and 16% had chronic renal insufficiency (1% on hemodialysis). Technical success was 92%, with 63% SFA undergoing angioplasty, 26% SFA undergoing primary stenting, and 3% SFA undergoing atherectomy. Overall mortality was 1.1% and overall morbidity was 17% at 90 days after the procedure. At 5 years, vessels with compromised and poor runoff had significantly lower freedom from recurrent symptoms and lower freedom from restenosis. Primary and assisted primary patency rates were significantly worse in patients with poor runoff. However, secondary patency was equivalent between the groups. Compromised or poor runoff was associated with incremental lower limb salvage. Following SFA percutaneous interventions for claudication, runoff can identify patients more likely to develop restenosis and recurrent symptoms and, more importantly, those at higher risk of limb loss. Defining such subgroups allows a clear risk stratification of patients with claudication and can guide the intensity of surveillance in the outpatient setting.

The Use of Covered Nitinol Stents to Salvage Dialysis Grafts After Multiple Failures

The increasing number of patients requiring hemodialysis and the limited number of access sites have resulted in an increase in multiple graft revisions to maintain access for hemodialysis. Venous outflow or anastomotic stenoses in vascular grafts tend to recur and contribute to the difficulty in maintaining a functioning graft. Thus, extending the life of a failed graft becomes an important objective of this study, which was to assess the use of covered nitinol stents to salvage expanded polytetrafluoroethylene (ePTFE) grafts with venous anastomotic or outflow stenosis that have failed after multiple revisions. This is a review of 8 failed nonautogenous ePTFE grafts with isolated venous anastomotic or proximal outflow stenoses that had undergone multiple previous revisions, had failed percutaneous transluminal angioplasty (PTA), and required placement of a covered nitinol stent. Graft locations were forearm (2), upper arm (4), and femoral (2). The mean number of interventions per patient before stent placement was 5.87 thrombectomies (range 2–28) and 3.38 balloon angioplasties (range 2–19). Five patients had 0.62 interposition grafting and 3 had patch angioplasty. All 8 patients (100%) underwent successful dialysis after thrombectomy and stenting. The primary and secondary patency rates after stent placement were 50% and 75%, and 25% and 75%, at 3 and 6 months, respectively. Percutaneous thrombectomy, balloon angioplasty, and concomitant covered nitinol stent placement extend the function of hemodialysis access grafts that have previously failed multiple times.

Transcranial Doppler findings during thoracic endovascular aortic repair

OBJECTIVE Thoracic endograft placement has become an acceptable treatment alternative to open repair of the thoracic aorta. Cerebral embolization when manipulating the aortic arch during cardiac catheterization is well described, but the influence of thoracic endovascular aortic repair (TEVAR) on this event remains poorly studied. Our aim was to quantify the number of microembolic signals (MES) detected by transcranial Doppler (TCD) during different stages of TEVAR and correlate them with landing zones, subclavian revascularization, and postoperative morbidity and mortality. METHODS TCD was used to monitor 20 patients during TEVAR for the treatment of thoracic aortic aneurysms (TAAs) in 17 (85%) patients, followed by three (15%) with chronic type B aortic dissection and one (5%) Crawford type I thoracoabdominal aortic aneurysm (TAAA). Imaging and medical parameters were entered into a combined database. TCD signals were recorded digitally for the entire case. MES, velocities, and pulsatility index values were entered into a combined database. RESULTS The total number of MES calculated for the diagnostic phase before TEVAR placement and during the treatment phase for all cases combined was 1081 and 1141, respectively. The highest MES counts were generated by the pigtail catheter placement during the diagnostic phase and by device placement during the treatment phase. Embolic count to right/left sides was equal overall. In the diagnostic phase, an average of nine MES were seen right/left, whereas during the treatment phase, 45 and 43 MES were seen, respectively, for right/left. A significant association was found between the total number of MES and postoperative stroke, transient ischemic attack (P = .0055), and death (P = .0053). CONCLUSIONS TCD can detect microemboli during TEVAR and is able to identify the procedural aspects most associated with cerebral microemboli.