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Gregorio A Sicard

Publications and source records attributed to Gregorio A Sicard.

At least 19 recordsLinked to original sources

Endovascular repair of thoracic aortic lesions using infrarenal devices: lessons learned and continued applications.

The application of endovascular devices for the treatment of a variety of thoracic aortic lesions has flourished worldwide over the past decade. Until physicians become facile with recently approved thoracic devices and these devices are immediately available even in emergency situations, the use of endovascular abdominal components offers physicians more options in managing thoracic lesions. We evaluated the safety, efficacy, and outcomes of commercially available, infrarenal endovascular graft components for managing lesions of the thoracic aorta. Nineteen patients were treated outside of a clinical trial using commercially available endovascular devices. The indications for treatment included acute traumatic lesions (n = 7), symptomatic ulcers (n = 4), focal aneurysms or pseudoaneurysms (n = 7), and symptomatic type B dissection (n = 1). The endovascular components included Excluder Aortic Cuffs (n = 9), AneuRx Aortic Cuffs (n = 5), Zenith Aortic Cuffs (n = 2), Zenith Aortic Tube Grafts (n = 2), and graft combinations (n = 1). Seventeen patients (89%) underwent successful endovascular treatment of their thoracic lesion. One patient required elective surgical conversion, and a second patient had a dissection that was not completely sealed endovascularly. There was no periprocedural mortality, and the major complication rate was 16% (3/19). Two patients had asymptomatic troponin leaks, and one patient developed an iliac rupture at the device introduction site, hypotension, and paraplegia. At a mean follow-up of 12.3 months, all successfully treated patients continue to have complete exclusion of the treated lesion. Infrarenal endovascular graft components can be very useful in the treatment of selected patients with amenable thoracic lesions until thoracic devices are available in all necessary sizes, readily accessible to treating physicians, and cost-effective.

Adult↗

Endovascular abdominal aortic aneurysm repair: long-term outcome measures in patients at high-risk for open surgery.

PURPOSE: The study was conducted to determine the outcome in the United States after endovascular repair (EVAR) of infrarenal abdominal aortic aneurysms (AAAs) in patients at high-risk for open surgery by using independently audited, high-compliance, chart-verified data sets, and to compare those results with open surgery. METHODS: High-risk was defined to match a recent European trial (EVAR2) and included age of > or =60 years with aneurysm size of > or =5.5 cm, plus at least one cardiac, pulmonary, or renal comorbidity. Data from five multicenter investigational device exemption clinical trials leading to Food and Drug Administration (FDA) approval were analyzed. Of 2216 EVAR patients, 565 met the high-risk criteria. Of 342 surgical controls (OPEN), 61 met high-risk criteria. Primary outcome comparisons included AAA-related death, all-cause death, and aneurysm rupture. Secondary measures were endoleak, AAA sac enlargement, and migration. RESULTS: Average age of the high-risk EVAR subset was 76 +/- 7 years vs 74 +/- 6 years OPEN (P = 0.07), mean EVAR AAA size was 6.4 +/- 0.8 cm vs 6.6 +/- 1.0 cm OPEN (P = .33), and average EVAR follow-up was 2.7 years vs 2.5 years OPEN. The 30-day operative mortality was 2.9% in EVAR vs 5.1% in OPEN (P = .32). The AAA-related death rate after EVAR was 3.0% at 1 year and 4.2% at 4 years compared with 5.1% at both time points after OPEN (P = .58). Overall survival at 4 years after EVAR was 56% vs 66% in OPEN (P = .23). After treatment, EVAR successfully prevented rupture in 99.5% at 1 year and in 97.2% at 4 years. CONCLUSIONS: Endovascular repair of large infrarenal AAAs in anatomically suited high-surgical-risk patients using FDA-approved devices in the United States is safe and provides lasting protection from AAA-related mortality. EVAR mortality remained comparable with OPEN up to 4 years. The decision to treat AAAs in patients with advanced age and significant comorbidities must be individualized and carefully considered, but repair provides excellent protection from AAA-related death.

Aged↗

Treatment of asymptomatic carotid artery disease: similar early outcomes after carotid stenting for high-risk patients and endarterectomy for standard-risk patients.

BACKGROUND: The role of carotid angioplasty and stenting (CAS) in the treatment of asymptomatic patients with carotid disease remains controversial. The purpose of this report is to compare outcomes in asymptomatic patients treated with CAS and carotid endarterectomy (CEA). This was the initial experience performing CAS for most of the surgeons. For comparison, we also report our outcomes in standard-risk patients treated concurrently with CEA during the same period of time. METHODS: A retrospective, nonrandomized review of asymptomatic patients undergoing CEA or CAS at Washington University Medical Center in St. Louis was done. Patients with >70% asymptomatic carotid stenosis treated between September 2003 and April 2005 were identified. CEA was the first therapeutic consideration in all patients. CAS was reserved for high-risk patients. Thirty-day outcomes of stroke or death were recorded. During this time interval, 248 patients were treated including with 93 CAS and with 145 CEA. Symptomatic or clinically detected adverse outcomes such as myocardial infarction (MI), arrhythmia, renal failure, or pulmonary complications were noted but were not the primary end points of this review. This study addresses only the periprocedural outcomes of CEA and CAS in asymptomatic patients. No data >30-day follow-up are included. RESULTS: During this period, 93 CAS and 145 CEA procedures were done in asymptomatic patients. Patient characteristics in both groups were similar. Carotid protection devices were used in 91.4% of CAS patients. The results in the CAS group showed one death (1.1%) and one stroke (1.1%). In the CEA group, three strokes occurred (2.1%, P = 0.9999), one associated with death (0.7%, P = 0.9999). The CAS group had 1.34 +/- 0.83 risk factors vs 0.39 +/- 0.58 in the CEA group (P < .0001). Median CAS and CEA length of stay was 1 day. CONCLUSIONS: CAS for asymptomatic carotid stenosis demonstrated equivalent outcomes compared with CEA, despite CAS being reserved for use in a disadvantaged subset of high-risk patients owing to anatomic risk factors or medical comorbidities. These results suggest CAS should be considered a reasonable treatment option in the high-risk but asymptomatic patient. Enthusiasm for CAS should be tempered by the recognition that long-term outcomes in CAS-treated asymptomatic patients remain unknown.

Aged↗

Elective surgery for thoracic aortic aneurysms: late functional status and quality of life.

BACKGROUND: Elective surgical treatment for thoracic aortic aneurysms is unique in that it is often performed on asymptomatic patients. Although it has been found to improve survival, the impact of elective surgery on late functional status and quality of life have yet to be examined. METHODS: Over a 5-year period, 110 asymptomatic patients underwent elective thoracic aortic replacement for ascending, descending, or thoracoabdominal aneurysms. Mean age was 67 +/- 9 years (53 > or = 70 years). Functional status, physical and psychological quality of life (Medical Outcome Study 36-Item Short Form Health Survey, in which 50 represents normalized age-matched US population), and survival (Kaplan-Meier) were assessed. RESULTS: Return to normal activity level was independent of age (p > 0.59) and procedure (p > 0.18). At 35 +/- 20 months, psychological quality of life was similar between surgical groups (p > 0.71), but physical quality of life was lower after thoracoabdominal versus ascending or descending aneurysms (p < 0.02). Age did not impact physical quality of life (40 +/- 13 > or = 70 years versus 42 +/- 11 < 70 years, p > 0.58), but older patients had improved psychological quality of life (52 +/- 9 > or = 70 years versus 47 +/- 8 < 70 years, p > 0.03). Overall survival was 79% +/- 4% at 2 years and 70% +/- 5% at 4 years, but was lower with thoracoabdominal versus ascending or descending aneurysms (p < 0.002). Multivariate analysis identified thoracoabdominal (p < 0.004), advanced age (p < 0.03), chronic renal failure (p < 0.03), and congestive heart failure (p < 0.001) as predictors of late death. CONCLUSIONS: Advanced age did not impair return to normal functional status, and older patients had improved psychological quality of life. Survival and physical quality of life were lowest with thoracoabdominal versus ascending or descending aneurysms. Thus, patients with asymptomatic thoracic aneurysms should not be denied elective replacement based on age alone, as functional recovery was not significantly impaired.

Aged↗

Glomerular filtration rate is a predictor of mortality after endovascular abdominal aortic aneurysm repair.

OBJECTIVE: Clinically evident renal disease is a risk factor for mortality after aneurysm repair. Serum creatinine is widely used as a measure of renal function in the preoperative evaluation of patients. Unfortunately, serum creatinine concentration is influenced by muscle mass, hydration status, and glomerular filtration rate (GFR). Calculated GFR, which takes predictors of muscle mass such as age, gender, and weight into account, is a more sensitive determinant of renal function than serum creatinine. We hypothesized that GFR would more accurately predict mortality after EVAR than serum creatinine. METHODS: We retrospectively evaluated our database of 398 patients who underwent EVAR with the AneuRx device between October 1999 and October 2004. There were 340 men and 58 women with a mean age of 73. GFR was calculated using the Cockcroft-Gault equation. The patients were divided into four quartiles by preoperative GFR: I (7 to 45), II (45 to 60), III (61 to 79), and IV (> or =80). Survival was estimated with the Kaplan-Meier method, and heterogeneity of mortality across strata was evaluated using the log-rank test. The GFR quartiles were compared with clinically accepted criteria for abnormal renal function (serum creatinine level > or =1.7). RESULTS: Actuarial survival at 48 months was 61.5%, 70.5%, 86.0%, and 85.7% for GFR quartiles I to IV, respectively (P < .003). Thirty-day mortality was 2.2% in quartile I, 3.2% in quartile II, and 0 in quartiles III and IV (P = .03 for q1 + q2 vs q3 + q4, P < .02 for q2 vs q3 + q4). Survival curves for quartiles II to IV were statistically indistinguishable, with quartile II running tangential to the two higher quartiles after the perioperative period. Quartile I fared significantly worse than the other three quartiles for the entire follow-up period (P < .005). According to American Kidney Foundation criteria (GFR <90), 83.3% of patients had abnormal renal function compared with 16.1% with abnormal serum creatinine (>1.7) (P < .0002). CONCLUSION: The risk of perioperative and long-term mortality in patients undergoing EVAR is more accurately stratified by using calculated GFR than serum creatinine alone. A GFR <45 is associated with decreased survival after EVAR. Perioperative mortality at a GFR of 45 to 60 is comparable with that of the lower quartile (GFR <45), but late survival is comparable with that of patients with GFR >60. The finding of increased risk of early mortality in patients in the 45 to 60 GFR range, with survivors enjoying good long-term outcome, suggests that these patients may most benefit from the use of alternative contrast agents and periprocedural renal protection techniques.

Aged↗

Effect of challenging neck anatomy on mid-term migration rates in AneuRx endografts.

OBJECTIVE: To establish the effect of challenging neck anatomy on the mid- and long-term incidence of migration with the AneuRx bifurcated device in patients treated after Food and Drug Administration approval and to identify the predictive factors for device migration. METHODS: Prospectively maintained databases at the University of North Carolina (UNC) and Washington University (WU) were used to identify 595 patients (UNC, n = 230; WU, n = 365) who underwent endovascular repair of an infrarenal abdominal aortic aneurysm with the AneuRx bifurcated stent graft. Those patients with at least 30 months of follow-up were identified and underwent further assessment of migration (UNC, n = 25; WU, n = 59) by use of multiplanar reconstructed computed tomographic scans. RESULTS: Eighty-four patients with a mean follow-up time of 40.3 months (range, 30-55 months) were studied. Seventy percent of the patients (n = 59) met all inclusion criteria for neck anatomy (length, angle, diameter, and quality) as defined by the revised instructions for use guidelines and are referred to as those with favorable neck anatomy (FNA). The remaining 25 patients retrospectively fell outside of the revised instructions for use guidelines and are referred to as those with unfavorable neck anatomy (UFNA). Life-table analysis for FNA patients at 2 and 4 years revealed a migration rate of 0% and 6.1%, respectively. For UFNA patients, it was 24.0% and 42.1% at 2 and 4 years, respectively (P < .0001). The overall (FNA and UFNA) migration rate was 7.1% and 17.1% at 2 and 4 years, respectively. Overall, late graft-related complications occurred in 38% of patients (FNA, 27%; UFNA, 64%; P = .003; relative risk, 1.7). There was no incidence of late rupture or open conversion. The relative risk of migration for UFNA patients was 2.5 compared with FNA patients (P = .0003). A larger neck angle and a longer initial graft to renal artery distance were predictors of migration, whereas shorter neck length approached but did not reach statistical significance. CONCLUSIONS: Patients who have unfavorable aneurysm neck anatomy experience significantly higher migration, device-related complication, and secondary intervention rates. However, there was no incidence of open conversion, rupture, or abdominal aortic aneurysm-related death, thereby supporting the AneuRx device as a feasible alternative to open repair even in patients with challenging neck characteristics. Enhanced surveillance should be used in these high-risk patients.

Aged↗

Coronary artery calcification and risk factors for atherosclerosis in patients with venous thromboembolism.

BACKGROUND: Venous thromboembolism (VTE) and atherosclerosis may be associated and may share common risk factors. We conducted a retrospective case-control study to investigate the association between VTE and coronary atherosclerotic disease (CAD) by means of measuring coronary artery calcification and evaluating clinical risk factors. METHODS: From 385 consecutive patients suspected of VTE, we randomly selected 89 cases with idiopathic VTE and 89 controls without VTE, frequency matched on gender and age. Risk factors for atherosclerosis were noted for both groups. Coronary artery calcification was quantified on pulmonary computed tomography (CT) angiographic images. The coronary artery calcification and risk factors were compared between the case and control groups. The associations between VTE and the presence of coronary artery calcium and risk factors were assessed with logistic regression analysis. RESULTS: A higher prevalence of coronary artery calcium was found in the case group (51.7%) than in the control group (28.1%) (p=0.001). The presence of coronary artery calcium was significantly associated with VTE with an odds ratio of 4.3 (95% confidence interval, 1.9-10.1) in a multivariable model. Diabetes mellitus and hypertension were also significantly associated with VTE. CONCLUSION: A significant association between VTE and CAD suggests that CAD is an independent risk factor for VTE. Diabetes and hypertension are also independent risk factors for VTE.

Adult↗

Aortic neck attachment failure and the AneuRx graft: incidence, treatment options, and early results.

Some investigators have reported that proximal attachment failure is a long-term complication of endovascular abdominal aortic aneurysm repair (EVAR) with the AneuRx (Medtronic, Santa Rosa, CA) device. We evaluated the need for an intervention in patients with suboptimal proximal fixation as well as the feasibility and early success of a variety of treatment strategies. From October 1999 to October 2003, we performed 365 EVARs using the AneuRx graft. At a mean follow-up of 23.7 +/- 14.8 months, 20 patients (5.5%) with suboptimal outcomes (14 with a type I endoleak, one with a type III endoleak, and 5 with an inadequate seal zone <1 cm) were considered for treatment. Characteristics of each patient''s aortic neck anatomy that could be associated with proximal attachment failure were evaluated. Eighteen patients (90%) underwent successful treatment (9 AneuRx cuffs, 6 Talent cuffs, 5 aortic stents, one redo endograft, and two surgical conversions) without major perioperative complications, one patient had a persistent type I endoleak despite endovascular treatment, and one patient refused treatment, ultimately leading to aneurysm rupture. There have been no further endoleaks or graft migrations noted since the secondary intervention at a mean follow-up of 13.9 +/- 11.8 months. In our experience, proximal attachment failure associated with the AneuRx graft is relatively uncommon and usually associated with unfavorable neck anatomy. Despite this, most cases are treatable by endovascular means. Long-term follow-up is needed to assess the ultimate frequency of these combined device reconstructions.

Aged↗

Local maximal stress hypothesis and computational plaque vulnerability index for atherosclerotic plaque assessment.

It is believed that atherosclerotic plaque rupture may be related to maximal stress conditions in the plaque. More careful examination of stress distributions in plaques reveals that it may be the local stress/strain behaviors at critical sites such as very thin plaque cap and locations with plaque cap weakness that are more closely related to plaque rupture risk. A "local maximal stress hypothesis" and a stress-based computational plaque vulnerability index (CPVI) are proposed to assess plaque vulnerability. A critical site selection (CSS) method is proposed to identify critical sites in the plaque and critical stress conditions which are be used to determine CPVI values. Our initial results based on 34 2D MRI slices from 14 human coronary plaque samples indicate that CPVI plaque assessment has an 85% agreement rate (91% if the square root of stress values is used) with assessment given by histopathological analysis. Large-scale and long-term patient studies are needed to further validate our findings for more accurate quantitative plaque vulnerability assessment.

Coronary Artery Disease↗

Endovascular treatment of an internal carotid artery thrombus using reversal of flow: a case report.

A case of a symptomatic free-floating thrombus of the internal carotid artery is described. A 51-year-old woman presented with a transient ischemic attack and was placed on anticoagulation after diagnosis with angiography. After medical therapy failed, she underwent suction embolectomy using reversal of flow with the Parodi Anti-Embolism System. Balloon angioplasty was performed, and a stent was placed. The patient tolerated the procedure well. A follow-up carotid ultrasound scan showed resolution of the thrombus.

Angioplasty, Balloon↗

Long-term functionality of cryopreserved parathyroid autografts: a 13-year prospective analysis.

BACKGROUND: The functional results of cryopreserved heterotopic parathyroid autotransplantation (CHPA) are not well defined. The authors evaluated the outcomes of delayed CHPA for the treatment of surgically induced hypoparathyroidism. METHODS: Since November 1991, 448 parathyroid samples from 436 patients were cryopreserved at our institution. Of these, 29 patients underwent 34 CHPA procedures, with placement of 20 to 25 pieces of parathyroid tissue (approximately 50 to 75 mg) into the forearm. Outcomes were determined based on peripheral parathyroid hormone (PTH) levels and, where available, PTH gradients between grafted and nongrafted arms. Graft function results were defined as completely functional (patients with normal PTH and calcium levels off all calcium/vitamin D supplementation), partially functional (normal PTH levels and mild hypocalcemia on calcium supplementation), or nonfunctional (low PTH levels and dependent on calcium/vitamin D supplementation). RESULTS: Of the 29 patients with CHPA, prospective data were available for 26 patients undergoing 30 CHPA procedures (9 patients with MEN 1, 4 with MEN 2A, 1 with MEN 2B, and 12 with sporadic hyperparathyroidism). The mean follow-up interval was 2 years. Twelve of 26 patients (46%) had completely functional grafts, 6 patients (23%) had partially functional grafts, and the remaining 8 patients (31%) had nonfunctional grafts. No patient with CHPA had graft-dependent recurrent hyperparathyroidism. Of the 14 patients (15 autografts) with MEN, 7 patients (50%) had fully functional grafts, and 2 patients (14%) had partially functional grafts. The mean cryopreservation period was 7.9 months (range, 1 week to 22 months) for functional autografts and 15.3 months (range, 2 weeks to 106 months) for nonfunctional autografts (P < .01). CONCLUSIONS: Based on these data and those in previous studies, approximately 60% of delayed, cryopreserved parathyroid autografts are functional. In this study 40% autografts (46% of patients) achieved full competency off supplements. Some patients have evidence of graft function with normal PTH levels but are not normocalcemic. Results were similar for patients with MEN and nonhereditary hyperparathyroidism. The duration of cryopreservation was a significant indicator of graft failure, and no functional autograft was observed beyond 22 months of preservation. CHPA is a useful treatment modality for patients with postoperative hypocalcemia after thyroid or parathyroid surgery, who do not respond to immediate parathyroid autotransplantation.

Adolescent↗

Quantifying effects of plaque structure and material properties on stress distributions in human atherosclerotic plaques using 3D FSI models.

BACKGROUND: Atherosclerotic plaques may rupture without warning and cause acute cardiovascular syndromes such as heart attack and stroke. Methods to assess plaque vulnerability noninvasively and predict possible plaque rupture are urgently needed. METHOD: MRI-based three-dimensional unsteady models for human atherosclerotic plaques with multi-component plaque structure and fluid-structure interactions are introduced to perform mechanical analysis for human atherosclerotic plaques. RESULTS: Stress variations on critical sites such as a thin cap in the plaque can be 300% higher than that at other normal sites. Large calcification block considerably changes stress/strain distributions. Stiffness variations of plaque components (50% reduction or 100% increase) may affect maximal stress values by 20-50%. Plaque cap erosion causes almost no change on maximal stress level at the cap, but leads to 50% increase in maximal strain value. CONCLUSIONS: Effects caused by atherosclerotic plaque structure, cap thickness and erosion, material properties, and pulsating pressure conditions on stress/strain distributions in the plaque are quantified by extensive computational case studies and parameter evaluations. Computational mechanical analysis has good potential to improve accuracy of plaque vulnerability assessment.

Blood Pressure↗

Acute thromboembolic events during carotid artery angioplasty and stenting: etiology and a technique of neurorescue.

PURPOSE: To review the protected carotid stenting experience at two major referral centers to evaluate the frequency of clinically significant intraprocedural thromboembolic events, use of neurorescue techniques, and ultimate clinical outcomes. METHODS: A retrospective review was conducted of 254 cases of protected transfemoral carotid stenting performed at the Washington University-Barnes Hospital and The Fleni Institute of Buenos Aires in a 6-year period. Medical records of patients with periprocedural thromboembolic events were reviewed to determine the type of complication, method of treatment, and outcome. RESULTS: Among the 254 cases in which a carotid protection device was used, 2 (0.79%) episodes of witnessed, symptomatic thromboembolism occurred. Both patients suffered thromboembolic occlusion of the M1 branch of the middle cerebral artery (MCA) immediately following crossing of the internal carotid lesion with the protection device. Neurological symptoms consisted of agitation, aphasia, and hemiplegia in both patients. After rapid stent deployment across the carotid lesion, the MCA was cannulated and the occlusion treated with balloon angioplasty. This was followed by selective intra-arterial delivery of urokinase and intravenous abciximab. These maneuvers resulted in excellent restoration of blood flow in the MCA and its branches. With the exception of minor word-finding difficulties in one, both patients demonstrated full neurological recovery within the perioperative period. CONCLUSIONS: In our experience, intraprocedural thromboembolic events occur despite the use of cerebral protection devices, but are rare. Notably these complications appeared to occur at the time of lesion crossing by distal cerebral protection devices. These thromboembolic events can be successfully treated if the complication is rapidly identified and the physician is adequately prepared and proficient in neurorescue techniques.

Abciximab↗

Type II endoleak after endovascular abdominal aortic aneurysm repair: a conservative approach with selective intervention is safe and cost-effective.

OBJECTIVES: The conservative versus therapeutic approach to type II endoleak after endovascular repair of abdominal aortic aneurysm (EVAR) has been controversial. The purpose of this study was to evaluate the safety and cost-effectiveness of the conservative approach of embolizing type II endoleak only when persistent for more than 6 months and associated with aneurysm sac growth of 5 mm or more. METHODS: Data for 486 consecutive patients who underwent EVAR were analyzed for incidence and outcome of type II endoleaks. Spiral computed tomography (CT) scans were reviewed, and patient outcome was evaluated at either office visit or telephone contact. Patients with new or late-appearing type II endoleak were evaluated with spiral CT at 6-month intervals to evaluate both persistence of the endoleak and size of the aneurysm sac. Persistent (>or=6 months) type II endoleak and aneurysm sac growth of 5 mm or greater were treated with either translumbar glue or coil embolization of the lumbar source, or transarterial coil embolization of the inferior mesenteric artery. RESULTS: Type II endoleaks were detected in 90 (18.5%) patients. With a mean follow-up of 21.7 +/- 16 months, only 35 (7.2%) patients had type II endoleak that persisted for 6 months or longer. Aneurysm sac enlargement was noted in 5 patients, representing 1% of the total series. All 5 patients underwent successful translumbar sac embolization (n = 4) or transarterial inferior mesenteric artery embolization (n = 4) at a mean follow-up of 18.2 +/- 8.0 months, with no recurrence or aneurysm sac growth. No patient with treated or untreated type II endoleak has had rupture of the aneurysm. The mean global cost for treatment of persistent type II endoleak associated with aneurysm sac growth was US dollars 6695.50 (hospital cost plus physician reimbursement). Treatment in the 30 patients with persistent type II endoleak but no aneurysm sac growth would have represented an additional cost of US dollars 200000 or more. The presence or absence of a type II endoleak did not affect survival (78% vs 73%) at 48 months. CONCLUSIONS: Selective intervention to treat type II endoleak that persists for 6 months and is associated with aneurysm enlargement seems to be both safe and cost-effective. Longer follow-up will determine whether this conservative approach to management of type II endoleak is the standard of care.

Aortic Aneurysm, Abdominal↗