Biomedical subjects

Lee R Guterman

Publications and source records attributed to Lee R Guterman.

63 records · Page 4Linked to original sources

PubMed2002

Stent-assisted endoluminal revascularization for the treatment of intracranial atherosclerotic disease.

Since the inception of intravascular stents in the 1960s, marked technological advancements have yielded stents that can be navigated through tortuous cerebral vessels. Numerous applications for intracranial stenting are being developed at an exciting pace. One such application that has shown promise in several small series is the use of stents for endoluminal revascularization of severe intracranial stenosis that is refractory to medical therapy. Prior to the introduction of endovascular approaches for this condition, complex bypass procedures were often necessary to restore adequate blood flow to hypoperfused parenchyma. In the following article, we review endovascular techniques for stenting of intracranial atherosclerotic disease. Patient selection, vascular access, medical management, and future directions are discussed.

Angioplasty↗

PubMed2002

Stent placement for the treatment of occlusive atherosclerotic carotid artery disease in patients with concomitant coronary artery disease.

OBJECT: The authors report their experience with carotid artery stent placement (CASP) in patients with concomitant carotid artery (CA) and coronary artery (CorA) diseases. METHODS: In a review of 320 consecutive patients who underwent CASP, the authors identified 49 with severe CorA disease in addition to significant CA stenosis, who had undergone CASP before planned CorA bypass grafting (CorABG). The average age of these 49 patients was 68 years. In 39 patients (80%) the New York Heart Association functional classification grade was IV and in 10 the grade was III. In 26 patients 50% or greater stenosis of the left main CorA was found. Seventeen patients (35%) suffered from either significant hemodynamic contralateral CA stenosis (> 60% stenosis; eight patients) or contralateral CA occlusion (nine patients). Sixteen patients (33%) had symptomatic CA disease. No cerebrovascular events occurred during CorABG. Four patients (8%) died of cardiac arrest and one patient (2%) suffered a major stroke within 30 days after the CorABG procedure. No patient experienced clinically significant recurrent CA stenosis during the study period (average clinical follow-up period 27 months). CONCLUSIONS: Carotid artery stent placement should be considered as an alternative for the management of concomitant CA and CorA diseases. These preliminary results support the feasibility and durability of CASP in the population studied.

Aged↗

PubMed2002

Staged stent-assisted angioplasty for symptomatic intracranial vertebrobasilar artery stenosis.

OBJECT: Medically refractory symptomatic vertebrobasilar atherosclerotic disease has a poor prognosis. Studies have shown that longer (> or = 10 mm), eccentric, high-grade (> 70%) stenoses portend increased procedure-related morbidity. The authors reviewed their experience to determine whether a staged procedure consisting of angioplasty followed by delayed (> or = 1 month later) repeated angioplasty and stent placement reduces the morbidity associated with endovascular treatment of symptomatic basilar and/or intracranial vertebral artery (VA) stenoses. METHODS: The authors retrospectively reviewed the medical records in a consecutive series of eight patients who underwent planned stent-assisted angioplasty for medically refractory, symptomatic atherosclerotic disease of the intracranial posterior circulation between February 1999 and January 2002. Staged stent-assisted angioplasty was planned for these patients because the extent and degree of stenosis of the VA and/or basilar artery (BA) lesion portended an excessive procedure-related risk. The degree of stenosis, recent onset of symptoms (unstable plaque), vessel tortuosity, and lesion length and morphological feaures were contributing factors in determining procedure-related risk. Patient records were analyzed for location and degree of stenosis, preprocedural regimen of antiplatelet and/or anticoagulation agents, devices used, procedure-related complications, and clinical and radiographic outcomes. Among the patients in whom staged stent-assisted angioplasty was planned, vessel dissection, which necessitated immediate stent placement, occurred during passage of the balloon in one of them. In a second patient, the stent could not be maneuvered through the tortuous VA. In a third patient, the VA and BAs remained widely patent after angioplasty alone, and therefore stent placement was not required. Significant complications among the eight patients included transient aphasia and hemiparesis in one and a groin hematoma that necessitated surgical intervention in another; there was no permanent neurological morbidity. The mean stenosis before treatment was 78%, which fell to 54% after angioplasty, and the mean residual stenosis after stent placement was 30%. At the last follow-up examination, none of the treated patients had further symptoms attributable to the treated stenosis. CONCLUSIONS: The novel combination of initial angioplasty followed by delayed endoluminal stent placement may reduce the neurological morbidity associated with endovascular treatment of long, high-grade stenotic lesions. Attempting to cross high-grade stenoses with higher-profile devices such as stents may result in an embolic shower. Furthermore, neointimal proliferation and scar formation after angioplasty result in a thickened fibrous layer, which may be protective during delayed stent deployment. Larger-scale studies involving multiple centers are needed to elucidate further the lesion morphological characteristics and patient population most likely to benefit from staged procedures.

Aged↗

PubMed2002

Apolipoproteins A-1 and B and the likelihood of non-fatal stroke and myocardial infarction -- data from The Third National Health and Nutrition Examination Survey.

BACKGROUND: The measurement of plasma apolipoproteins (APO) has been proposed for predicting the risk of cardiovascular diseases. However, the association between APOs and stroke is not well defined. MATERIAL/METHODS: We evaluated the association between plasma concentrations of APO A-1 and APO B with a physician diagnosis of stroke (n=153), and electrocardiogram evidence or physician diagnosis of myocardial infarction (n=379), in a nationally representative sample of 3,696 US adults aged >40 years who participated in the Third National Health and Nutrition Examination Survey. Multivariate logistic regression analyses were used to investigate these relationships. RESULTS: After adjusting for differences in age, gender, race/ethnicity, education, hypertension, cholesterol, body mass index, and cigarette smoking, the upper quartile of APO A-1 (> or = 161 mg/dl) when compared with the lowest quartile (<126 mg/dL) was inversely associated with the likelihood of myocardial infarction (Odds Ratio [OR], 0.6; 95% Confidence Interval [CI] 0.4-0.9) but not stroke. APO B concentrations were not associated with either myocardial infarction or stroke. However, an APO A-1 to B ratio > or = 1.59 when compared with a ratio < or = 1.04 was associated with a decreased likelihood of myocardial infarction (OR, 0.3; 95% CI, 0.2-0.6); and stroke (OR 0.4, 95% CI, 0.2-1.0). CONCLUSIONS: Higher APO A-1 concentrations were associated with a decreased likelihood for myocardial infarction but not for stroke. The APO A-1 to B ratio was inversely associated with both myocardial infarction and stroke and may be an important protective clinical marker for atherosclerosis.

Adult↗

PubMed2002

Transradial cerebral angiography: an alternative route.

INTRODUCTION: The transradial approach has been well described for arteriography of the coronary vessels. To assess the safety and success rate of the transradial approach for three-vessel or four-vessel diagnostic cerebral arteriography, we reviewed the experience at our institution and compared our complication rates with those found in the literature for transfemoral cerebral angiography and transradial coronary angiography. METHODS: We reviewed the electronic medical records of 129 consecutive patients in whom 132 cerebral angiographic studies were performed by use of a transradial approach between December 1999 and June 2001. A total of 54 selective catheterizations were performed, of which 39 were of the vertebral artery, 11 of the internal carotid artery, and 4 of the external carotid artery. Records were reviewed for periprocedural and delayed complications, indications for diagnostic angiography, and requirement of conversion to a femoral approach. Records were reviewed prospectively for the first 55 procedures and retrospectively for the next 77 procedures. RESULTS: The mean time to initial clinical follow-up was 1.5 months (median, 0.5 mo). The combined rate of periprocedural and delayed complications was 9%, and there were no major complications. Minor periprocedural complications included transient radial artery spasm (four patients), failure to access the brachial artery (two patients), severe pain (one patient), skin desquamation (one patient), and hematoma (one patient). There were no major complications. At the time of follow-up evaluation, these patients were without deficits related to cannulation of the radial artery. CONCLUSION: The transradial approach for cerebral angiography is a safe alternative to the transfemoral route. After transradial cerebral angiography, patients require a shorter observation period and are not restricted to bed rest. As technological developments generate smaller, more pliable endovascular surgical devices, future endovascular surgery may be performed transradially.

Adolescent↗

PubMed2002

Follow-up of stented carotid arteries by Doppler ultrasound.

OBJECTIVE: Blood flow velocity (BFV) in the carotid artery is altered by stent placement. The significance of these alterations is unknown. In our experience, both standard BFV criteria for stenosis and customized criteria recommended by other authors have led to high rates of false-positive studies. We reviewed our experience with Doppler ultrasonography immediately after extracranial carotid artery stent placement to define criteria for restenosis by BFV. METHODS: Complete carotid angiograms and BFV results were available for 114 patients treated between January 1998 and December 1999. Angiographic images obtained immediately after stent placement and at follow-up were measured for residual or recurrent stenosis by a blinded reviewer according to the North American Symptomatic Carotid Endarterectomy Trial method. Results of BFV studies obtained within 1 week of stent placement were interpreted by using two standard criteria (A, peak in-stent systolic velocity greater than 125 cm/s; B, internal carotid artery-to-common carotid artery ratio greater than 3.0) and two customized criteria (C, peak in-stent velocity greater than 170 cm/s; D, internal carotid artery-to-common carotid artery ratio greater than 2.0). The results of follow-up angiography and the most recent Doppler study were compared for nine patients. RESULTS: On the basis of an examination of Doppler studies obtained immediately after stent placement, 36 patients met Criterion A for stenosis according to measured BFV (corresponding mean angiographic stenosis, 14.73 +/- 18.45%), 3 patients met Criterion B (mean stenosis, 1.67 +/- 2.89%), 8 patients met Criterion C (mean stenosis, 12.61 +/- 13.18%), and 14 met Criterion D (mean stenosis, 7.98 +/- 21.74%). No patient with Doppler criteria for significant stenosis had more than 50% residual stenosis. Three of nine patients who underwent follow-up angiography had stenosis of 50% or more; of these three patients, two underwent second angioplasty procedures. The peak in-stent systolic velocity or internal carotid artery-to-common carotid artery BFV ratio for each of the three patients with restenosis, but not for the six other patients, had increased by more than 80% since the immediate post-stenting Doppler study. CONCLUSION: Strict BFV criteria for restenosis after carotid artery stenting are less reliable than change in BFV over time. An immediate post-stenting Doppler study must be obtained to serve as a reference value for future follow-up evaluation.

Aged↗

PubMed2002

Should interventional cardiologists treat ischemic strokes? A global perspective.

Stroke is the third leading cause of death and the leading cause of severe neurological disability in our nation. The stroke death rate has the potential to reach epidemic proportions as the elderly segment of the population continues to rise. There is an insufficient number of trained physicians to supply the care for this patient population. The logical source for qualified physicians to care for these patients is the interventional cardiologist. We review the recent intraarterial therapy trials and detail the training necessary to allow interventional cardiologists to treat ischemic strokes.

Cardiology↗

PubMed2002

Endovascular surgery: the future without limits.

The new millennium brings with it tremendous advances in technology and information sharing. Various medical, surgical, and engineering specialities are becoming more focused, thus enabling experts in these fields to gain insight and understanding previously unappreciated by those who came before us. Economic and technologic evolution will eliminate some of the drawbacks of endovascular therapy, such as persistent neck remnants. It is likely that drug delivery systems exist that would allow maximal benefit with little or no systemic adverse effects. It is likely that devices are available that could minimize various procedural complications. We as future neurosurgeons must persist in the quest to find collaborations that will promote cross-fertilization and cross-pollination among cardiologists, neurosurgeons, physicists, radiologists, neurologists, engineers, and other scientists so that the technology can be translated to reality. It is clear that, in time, transcatheter techniques will replace many operations for the treatment of cerebrovascular pathologies. Let us not allow ourselves the luxury of time.

Angioplasty↗

PubMedDate not supplied

Effect of endovascular treatment on headaches in patients with unruptured intracranial aneurysms.

BACKGROUND: Patients with unruptured intracranial aneurysms often present with headaches. OBJECTIVE: To determine the effect of endovascular treatment on the character and frequency of headaches in patients with unruptured intracranial aneurysms. METHODS: We reviewed the medical records of all patients who underwent endovascular treatment for unruptured intracranial aneurysms within a 9.5-year period. These patients were mailed a standard questionnaire in which they were asked about the frequency and character of any headache experienced before or after (or both) endovascular treatment. They were also asked to grade improvement or worsening of headaches after the procedure as mild (activities of daily living were not affected), moderate (activities of daily living were affected), or significant (the change resulted in an ability to perform new activities of daily living or an inability to perform previous activities of daily living). RESULTS: Forty-seven patients with unruptured aneurysms who underwent Guglielmi detachable coil embolization responded to the questionnaire. Of these, 32 patients (mean age, 52.7 years [SD, 13.4]; 22 were women) had experienced headaches before the procedure. Nineteen patients (59%) reported improvement in severity of headaches after embolization. Improvement was graded as significant by 7 patients, moderate by 8, and mild by 4. Two patients (6%) reported worsening severity of headaches graded as moderate. Five of 15 patients without headaches before embolization reported onset of mild (n = 4) or severe (n = 1) headaches after treatment. CONCLUSION: Guglielmi detachable coil embolization of unruptured intracranial aneurysms was associated with reduction in severity of headaches in the majority of patients who had experienced preprocedural headaches.

Activities of Daily Living↗