Biomedical subjects

Susan Trocciola

Publications and source records attributed to Susan Trocciola.

7 recordsLinked to original sources

PubMed2006

Cerebral ischemia associated with PercuSurge balloon occlusion balloon during carotid stenting: Incidence and possible mechanisms.

BACKGROUND: Interruption of antegrade cerebral perfusion results in transient neurologic intolerance in some patients undergoing carotid angioplasty and stenting (CAS). This study sought to evaluate factors that contributed to the development of cerebral ischemia during PercuSurge balloon occlusion and techniques used to allow successful completion of the CAS procedure. METHODS: The PercuSurge occlusion balloon was used in 43 of 165 patients treated with CAS for high-grade stenosis (mean stenosis, 90%). All 43 patients were at increased risk for endarterectomy (7 restenosis, 3 irradiation, 3 contralateral occlusion, and 30 Goldman class II-III); 20% were symptomatic. Symptoms of cerebral hypoperfusion during temporary occlusion of the internal carotid artery occurred in 10 of 43 and included dysarthria (7/10), agitation (6/10), decreased level of consciousness (5/10), and focal hemispheric deficit (3/10). An incomplete circle of Willis or contralateral carotid artery occlusion, or both, was present in 8 of 10 patients. Symptoms resulting from PercuSurge balloon occlusion were managed by balloon deflation with or without evacuation of blood from the internal carotid artery using the Export catheter. All symptoms resolved completely without deficit after deflation of the occlusion balloon. RESULTS: The development of neurologic symptoms after initial PercuSurge balloon inflation and occluded internal carotid artery flow was associated with a decrease in the mean Glasgow Coma Scale (GCS) from 15 to 10 (range, 9 to 14); the GCS returned to normal after occlusion balloon deflation and remained normal during subsequent reinflation. The mean time to spontaneous recovery of full neurologic function was 8 minutes (range, 4 to 15 minutes). No thrombotic or embolic events were present on cerebral angiography or computed tomography scan. Balloon reinflation was performed after a mean reperfusion interval of 10 minutes after full neurologic recovery (range, 4 to 20 minutes). The mean subsequent procedure duration was 11.9 minutes (range, 6 to 21 minutes). No recurrence of neurologic symptoms occurred when the occlusion balloon was reinflated. All 10 patients underwent successful CAS without occlusion, dissection, cerebrovascular accident, or death. CONCLUSION: Several factors may contribute to the development of neurologic intolerance during CAS with balloon occlusion. Elucidation of the protective cellular mechanisms that invoke ischemic tolerance after the initial transient ischemic event may enable CAS with embolic protection in patients who cannot tolerate initial interruption of antegrade cerebral perfusion.

Aged↗

PubMed2006

Evaluation of the accuracy of a wireless pressure sensor in a canine model of retrograde-collateral (type II) endoleak and correlation with histologic analysis.

BACKGROUND: The utility of intra-aneurysmal pressure determination is dependent on the ability to measure pressure in the presence of endoleak and thrombosis. In this study, the accuracy of a CardioMEMS wireless pressure sensor (CardioMEMS, Atlanta, Ga) transducer in the presence of thrombus associated with type II endoleak was measured. METHODS: Type II endoleaks were created in four mongrel dogs by implanting four collateral arterial side branches (lumbar and caudal mesenteric arteries) as a Carrel patch onto a 3-cm prosthetic polytetrafluoroethylene abdominal aortic aneurysm (AAA). The aneurysm was excluded 2 weeks later from antegrade perfusion by a stent graft. The wireless pressure sensor was positioned in the AAA external to the stent graft. A Konigsberg intraluminal solid-state strain-gauge pressure transducer (Konigsberg Instruments, Pasadena, Calif) that is accurate in the presence of thrombus served as the control to determine AAA pressure. Both of the transducers were implanted on the luminal surface of the aneurysm, 180 degrees opposite from the Carrel patch and endoleak channel. Intra-aneurysmal pressure resulting from the type II endoleak was measured twice daily for 4 weeks using both transducers. A total of 56 pre-exclusion and 224 post-exclusion distinct pressure determinations were made. Intra-aneurysmal pressure was indexed to the systemic pressure that was simultaneously measured by a strain-gauge pressure transducer implanted in the native aorta. Histologic analysis of the aneurysm contents was performed with hematoxylin and eosin. RESULTS: The intra-aneurysmal systolic, mean, and pulse pressures produced by the type II endoleak were significantly lower than systemic pressure in all animals and were < 60% of systemic pressure (P < .001). Close correlation between the wireless transducer and the control strain-gauge transducer was observed (R = 0.83, P < .001). Arteriography and Doppler ultrasound documented retrograde flow through the aneurysm side branches and persistent endoleak patency up to the time of euthanasia. Pathologic analysis demonstrated the endoleak channel to be patent and separated from the transducers by thrombus, which surrounded both transducers. CONCLUSIONS: Intra-aneurysmal pressure generated by type II endoleaks may be accurately measured through thrombus using a wireless pressure sensor in the canine model. The wireless sensor has the potential for clinical applicability in diagnosing and characterizing type II endoleaks.

Angioplasty↗

PubMed2005

A canine model to study the significance and hemodynamics of type II endoleaks.

OBJECTIVE: The clinical significance of Type 2 endoleak after endovascular repair of abdominal aortic aneurysms (AAA) remains incompletely delineated. This study describes the development of a novel canine model that allows for continuous monitoring of intraaneurysmal pressure in the setting of Type 2 endoleak. METHODS: Infrarenal AAA were created in 10 mongrel dogs by implanting a prosthetic aneurysm containing an intraluminal, solid-state, strain gauge pressure transducer which is able to measure pressures in both solid and liquid media. A segment of native aorta with two or more patent side branch vessels was reimplanted into the prosthetic aneurysm using a Carrel patch. Four animals had two lumbar vessels implanted; two had two lumbar vessels and the caudal mesenteric artery implanted, and four control animals had no vessels reimplanted. Retrograde flow in the aneurysmal side branches caused a Type 2 endoleak after the aneurysm was excluded from antegrade flow by deploying a stent graft. Both systemic and intra-sac pressures were measured daily for up to 90 days after endovascular exclusion and indexed to systemic pressure. Endoleak patency and flow were assessed with digital subtraction angiography, duplex ultrasound, and cine-magnetic resonance angiography (MRA). Histological characterization of the intraaneurysmal contents was performed. RESULTS: Before endovascular exclusion, the systolic, mean arterial, and pulse pressure within the aneurysmal sac closely matched that of the systemic circulation (systolic, 0.96 +/- 0.22; mean, 0.94 +/- 0.21; pulse pressure, 0.97 +/- 0.22) (R value, 0.97). Endovascular exclusion in animals with no collateral side branch vessels resulted in no endoleak and significantly reduced intraaneurysmal pressure when compared to systemic pressure, with systolic, mean arterial, and pulse pressure 0.172 +/- 0.05, 0.137 +/- 0.05, and 0.098 +/- 0.02, respectively (P < 0.001). In animals with Type 2 endoleaks, the pressures were lower than systemic pressure, but statistically significant in their difference from the control group. The systolic pressure of those with Type 2 endoleaks was 0.702 +/- 0.048; mean arterial pressure was 0.784 +/- 0.028, and pulse pressure was 0.406 +/- 0.031 when indexed to systemic pressure (P < 0.001). Cine-MRA and Duplex ultrasound documented persistent patency of the Type 2 endoleaks throughout the study period in animals with multiple side branches. CONCLUSION: Intraaneurysmal pressure in the setting of Type 2 endoleaks may be accurately determined using this canine model. Intraaneurysmal pressure is maintained at a significant level in the context of this retrograde collateral perfusion, suggesting that persistent Type 2 endoleaks are of clinical significance. This model may serve to allow further evaluation and characterization of Type 2 endoleaks.

Angiography, Digital Subtraction↗

PubMed2004

Computer simulation as a component of catheter-based training.

INTRODUCTION: Computer simulation has been used in a variety of training programs, ranging from airline piloting to general surgery. In this study we evaluate the use of simulation to train novice and advanced interventionalists in catheter-based techniques. METHODS: Twenty-one physicians underwent evaluation in a simulator training program that involved placement of a carotid stent. Five participants were highly experienced in catheter-based techniques (>300 percutaneous cases), including carotid angioplasty and stenting (CAS); the remaining 16 participants were interventional novices (<5 percutaneous cases). The Procedicus VIST simulator, composed of real-time vascular imaging simulation software and a tactile interface coupled to angiographic catheters and guide wires, was used. After didactic instruction regarding CAS and use of the simulator, each participant performed a simulated CAS procedure. The participant's performance was supervised and evaluated by an expert interventionalist on the basis of 50 specific procedural steps with a maximal score of 100. Specific techniques of guide wire and catheter manipulation were subjectively assessed on a scale of 0 to 5 points based on ability. After evaluation of the initial simulated CAS procedure, each participant received a minimum of 2 hours of individualized training by the expert interventionalist, with the VIST simulator. Each participant then performed a second simulated CAS procedure, which was graded with the same scale. After completion, participants assessed the training program and its utility via survey questionnaire. RESULTS: The average simulated score for novice participants after the training program improved significantly from 17.8 +/- 15.6 to 69.8 +/- 9.8 (P < .01), time to complete simulation decreased from 44 +/- 10 minutes to 30 +/- 8 minutes (P < .01), and fluoroscopy time decreased from 31 +/- 7 minutes to 23 +/- 7 minutes ( P < .01). No statistically significant difference in score, total time, or fluoroscopy time was noted for experienced interventionalists. Improvement was noted in guide wire and catheter manipulation skills in novices. Analysis of survey data from experienced interventionalists indicated that the simulated clinical scenarios were realistic and that the simulator could be a valuable tool if clinical and tactile feedback were improved. Novices also thought the simulated training was a valuable experience, and desired further training time. CONCLUSIONS: An endovascular training program using the Procedicus VIST haptic simulator resulted in significant improvement in trainee facility with catheter-based techniques in a simulated clinical setting. Novice participants derived the greatest benefit from simulator training in a mentored program, whereas experienced interventionalists did not seem to derive significant benefit.

Blood Vessel Prosthesis Implantation↗

PubMed2004

Stent graft treatment for abdominal aortic aneurysm repair: recent developments in therapy.

PURPOSE OF REVIEW: Minimally invasive endovascular techniques for the treatment of abdominal aortic aneurysms have significantly reduced the morbidity of these procedures compared with standard surgical repair. In addition, patients with extensive comorbid medical illnesses in whom standard operative repair is contraindicated may be successfully treated using endovascular means. RECENT FINDINGS: Recently, several important developments have significantly advanced this area of treatment. The Food and Drug Administration has approved four endovascular stent grafts for the treatment of abdominal aortic aneurysms: the Medtronic AneuRx, the W.L. Gore Excluder, the Cook Zenith, and the Guidant Ancure. The Zenith received approval for marketing in 2003 and has gained relatively wide use, in part because of its ability to treat aneurysms with relatively large-diameter implantations zones. Also in 2003, Guidant Corporation withdrew the Ancure graft from marketing and distribution. The withdrawal was influenced by difficulties encountered using the graft's delivery system and improper reporting to the Food and Drug Administration. Enrollment has also been recently completed for the phase II Food and Drug Administration trials of the Medtronic Talent graft and the Cordis Fortron graft. These devices have been approved for use in the European Union and are awaiting Food and Drug Administration panel meeting in the United States. Several significant advances have also occurred recently in stent graft research and development. Of particular significance has been the initiation of the phase I trial of the Trivascular Enovus graft. Deployment of the Trivascular graft may be accomplished through a delivery system that is considerably reduced in profile. The potential for percutaneous application of the graft may be available in the future. In selecting the specific stent graft to be used for endovascular abdominal aortic aneurysm repair, the specific graft characteristics must be considered, particularly with regard to the individual patient's anatomic and physiologic characteristics. Comparative analysis of the several of the various stent grafts has been performed. Results have varied with regard to the need for secondary interventions, aneurysm sac size reduction, and the occurrence of continued perfusion of the aneurysm sac. In addition, the indications for use of endovascular grafts compared with standard open surgery have not yet been fully defined. SUMMARY: This article describes the general principles of use for endovascular devices for the repair of abdominal aortic aneurysms. It details the features and results for the devices in current use, and highlights the recent developments in stent graft treatment of abdominal aortic aneurysms.

Aortic Aneurysm, Abdominal↗

PubMed2002

Donor immunization with pneumococcal conjugate vaccine and early protective antibody responses following allogeneic hematopoietic cell transplantation.

Patients undergoing hematopoietic cell transplantation (HCT) are at increased risk for infections with Streptococcus pneumoniae and have long-lasting, impaired antibody responses to pneumococcal polysaccharide vaccines. We examined whether donor immunization with a heptavalent pneumococcal conjugate vaccine (PCV7) would elicit protective antibody responses to additional doses of vaccine administered early after transplantation. Ninety-six patients scheduled to receive an allogeneic hematopoietic cell transplant were randomized with their donors to receive either a dose of PCV7 vaccine or no vaccine before transplantation. All patients received PCV7 at 3 months, 6 months, and 12 months following transplantation, and serotype-specific antibody concentrations were determined after each dose. Following HCT, geometric mean antibody concentrations of patients in the immunized donor group were significantly higher for 5 of the 7 vaccine serotypes after one dose (P <.05) and for 4 of the 7 serotypes after 2 doses of vaccine (P <.03). Sixty-seven percent of patients in the immunized donor group had presumed protective IgG concentrations more than or equal to 0.50 microg/mL to all 7 serotypes following the first dose of vaccine compared to 36% in the unimmunized donor group (P =.05). After the third dose of vaccine, both groups had more than 60% of patients with concentrations at least 0.50 microg/mL to all vaccine serotypes. Donor immunization enhances early antibody responses of patients undergoing HCT to pneumococcal conjugate vaccine. A 3-dose schedule of PCV7 vaccine at 3, 6, and 12 months is immunogenic in these patients regardless of donor immunization.

Adolescent↗

PubMedDate not supplied

Multimodal therapy for acute and chronic venous thrombotic and occlusive disease.

Critical deep venous thrombosis and occlusion constitutes a small percentage of patients with venous disease. However, these patients exhibit severe symptomatology including pain and extensive edema that may progress to limb- or life-threatening complications such as phlegmasia cerulea dolens and superior vena cava syndrome. This paper reviews the different multimodal percutaneous interventions currently available for the treatment of complex critical venous thrombotic and occlusive disease.

Acute Disease↗