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Dive into the research topics where Robert A. Graor is active.

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Featured researches published by Robert A. Graor.


Journal of Vascular and Interventional Radiology | 1995

Multicenter Trial of the Wallstent in the Iliac and Femoral Arteries

Eric C. Martin; Barry T. Katzen; James F. Benenati; Edward B. Diethrich; Gerald Dorros; Robert A. Graor; Keith M. Horton; Liberato A. lannone; Jeffrey M. Isner; Donald E. Schwarten; Charles J. Tegtmeyer; Craig M. Walker; Mark H. Wholey

PURPOSE To report the results of the FDA phase II, multicenter trial of the Wallstent in the iliac and femoral arteries. PATIENTS AND METHODS Two hundred twenty-five patients entered the trial. Stents were placed in the iliac system in 140 patients and in the femoral system in 90 (five patients required both iliac and femoral stents). Clinical patency was measured over 2 years by means of life-table analysis with use of clinical and hemodynamic data and the Rutherford scale. Angiographic patency was measured at 6 months. RESULTS In the iliac system the primary clinical patency was 81% at 1 year and was 71% at 2 years. The secondary clinical patency was 91% and 86%, respectively. The 6-month angiographic patency was 93%. In the femoral system the primary clinical patency was 61% at 1 year and 49% at 2 years. The secondary patency was 84% and 72%, respectively. The 6-month angiographic patency was 80%. CONCLUSIONS The results are similar to those with the Palmaz stent in the iliac system and with angioplasty alone in the iliac and femoral systems.


Journal of Vascular Surgery | 1988

Thrombolysis of peripheral arterial bypass grafts: Surgical thrombectomy compared with thrombolysis ☆ ☆☆: A preliminary report

Robert A. Graor; Barbara Risius; Jess R. Young; Fred V. Lucas; Edwin G. Beven; Norman R. Hertzer; Leonard P. Krajewski; Patrick J. O'Hara; Jeffrey W. Olin; William F. Ruschhaupt

Twenty-two patients were selected from a group of 33 patients who underwent recombinant human tissue-type plasminogen activator (rt-PA) thrombolysis for thrombosed infrainguinal bypass grafts of the lower extremity and were compared with 38 matched patients who had undergone surgical thrombectomy during the same period. The proportion of persons with diabetes mellitus, smokers, and types of bypass grafts was similar in both groups. More patients in the rt-PA-treated group had hypertension (p = 0.01). To evaluate the different lengths of follow-up, Kaplan-Meier survival analysis was used with a log-rank test to compare the proportion of persons with patent grafts in the two treatment groups. At 30 days, 86% of the rt-PA-treated grafts were still patent compared with 42% of the surgically treated grafts (p = 0.001). When risk factors on the Kaplan-Meier curves were compared, there was no statistical difference with regard to graft patency among the groups. According to simultaneous Cox regression analysis, no risk factor was significantly associated with graft patency. When amputation was evaluated between treatment groups simultaneously with other risk factors in a logistic regression analysis, smoking and age of the graft were marginally significant (p = 0.07), whereas all other factors were clearly not significant. In 91% of the rt-PA-treated patients, a secondary surgical procedure was required to maintain patency of the graft segment. Eighty-nine percent of the surgically treated patients required similar graft revisions. Two patients in the surgical group and one patient in the rt-PA-treated group had major complications.(ABSTRACT TRUNCATED AT 250 WORDS)


Journal of Vascular Surgery | 1985

Local thrombolysis in the treatment of thrombosed arteries, bypass grafts, and arteriovenous fistulas

Robert A. Graor; Barbara Risius; Kevin M. Denny; Jess R. Young; Edwin G. Beven; Norman R. Hertzer; William F. Ruschhaupt; Patrick J. O'Hara; Michael A. Geisinger; Margaret G. Zelch

We reviewed the results, systemic effects, and complications associated with the selective infusion of low-dose streptokinase in 151 patients. Successful thrombus lysis was achieved in 78% of atherosclerotic thrombotic occlusions less than 30 days old, in 81% of post-procedural occlusions less than 14 days old, and in 87% of patients with thrombosed arteriovenous fistulas no more than 4 days old. During the first 12 hours of treatment 81% to 84% of patients had greater than 50% decrease in plasma fibrinogen levels and 100% showed the same decline after 24 hours of treatment. The thrombin time was prolonged to at least 1 1/2 times the control thrombin time in 33% to 42% of patients measured at 4 hours of therapy and in 93% to 97% of patients measured at 24 hours of treatment. Fifteen patients (9.9%) had major complications. Eleven of these had hemorrhagic complications, two had significant distal emboli, one had a thrombosed brachial artery, and one had a false aneurysm at the catheter entry site. We have found that selective low-dose streptokinase is effective in the treatment of acute and chronic thrombotic occlusions and is a useful adjuvant to vascular reconstruction or percutaneous transluminal angioplasty. Although the local infusion dose is substantially lower than the usual systemic dose, a systemic lytic effect was seen in all patients. Hemorrhagic complications occurred despite customary precautions.


Journal of the American College of Cardiology | 1990

Transluminal atherectomy for occlusive peripheral vascular disease

Robert A. Graor; Patrick L. Whitlow

The failure of balloon angioplasty to provide a durable result has led to the development of other methods of catheter-associated interventional therapy. In this study, 112 patients with superficial femoral artery stenosis or occlusion were treated with percutaneous atherectomy. Patients were considered to have a simple lesion if the occluded or stenotic arterial segment was less than 5 cm, and a complex lesion if the length of the occluded segment was greater than 5 cm. All atherectomies were performed in the superficial femoral and popliteal arteries; urokinase thrombolysis was used in conjunction with atherectomy in 16 patients. Atherectomy was considered successful if there was less than 20% residual stenosis determined by arteriography. Initial atherectomy results (30 day patency) were 100% successful in the group with a simple lesion and 93% successful in the group with a complex lesion. At a mean follow-up period of 12 months (range 5 to 24), there was a continued patency rate of 93% and 86%, respectively, in the simple and complex groups. In the patients who had restenosis, all pathologic specimens obtained during the second procedure demonstrated myointimal hyperplasia and organized thrombus. Eight major complications (7.1%) occurred, including one fatal myocardial infarction. The complication rate was 3.5% in the simple group and 8.3% in the complex group. With the exception of the myocardial infarction, all complications were associated with catheter entry site hematomas. Femoropopliteal atherectomy has a high rate of success and low morbidity and mortality for both simple and complex lesions and is a viable and competitive alternative therapy for patients with severe peripheral vascular disease.(ABSTRACT TRUNCATED AT 250 WORDS)


Journal of Vascular Surgery | 1993

The incidence of deep venous thrombosis in patients undergoing abdominal aortic aneurysm resection

Jeffrey W. Olin; Robert A. Graor; Patrick J. O'Hara; Jess R. Young

PURPOSE Fifty consecutive patients undergoing abdominal aortic aneurysm resection were studied prospectively for the presence of deep venous thrombosis (DVT) after surgery. METHODS Bilateral venography was performed 5 days after surgery in all patients. There were 42 men and 8 women, with a mean age of 70 years (range 60 to 83 years). No patients received DVT prophylaxis before surgery. RESULTS Nine (18%) of 50 patients had a venogram positive for acute DVT. Nine (21%) of 42 men and none of eight women had DVT. Six patients had DVT in the left leg and three patients in the right leg. No patients had symptoms to suggest DVT. Seven (78%) of the nine patients with DVT had thrombi in the calf veins and two patients (22%) had thrombi in the more proximal venous segments, representing 14% and 4% of the entire series, respectively. No clinically evident pulmonary emboli were observed. CONCLUSIONS Eighteen percent of 50 consecutive patients undergoing abdominal aortic aneurysm resection had DVT. Because of this high incidence, a study should be undertaken to determine whether DVT prophylaxis can lower the incidence of DVT after abdominal aortic aneurysm resection.


Annals of Vascular Surgery | 1986

Coronary artery disease in patients with aortic aneurysm: a classification of 302 coronary angiograms and results of surgical management

Jess R. Young; Norman R. Hertzer; Edwin G. Beven; William F. Ruschhaupt; Robert A. Graor; Patrick J. O'Hara; Victor G. de Wolfe; John R. Kramer; Conrad Simpfendorfer

In an attempt to reduce early and late mortality caused by myocardial infarction in patients with aortic aneurysms, coronary arteriography and, when indicated, myocardial revascularization were performed prior to elective aortic reconstruction in 302 patients with infrarenal (289) or thoracoabdominal (13) aortic aneurysms. Severe correctable coronary artery disease (CAD) was identified in 31% of the entire series, whereas severe inoperable CAD was seen in another 5%. Severe, correctable CAD was documented in 42% of patients suspected to have CAD by standard clinical criteria and in 19% of those in whom CAD was not suspected. The overall mortality for 89 cardiac and 227 infrarenal aortic surgical procedures was 4,4%. Fatal complications after infrarenal aneurysm resection occurred in only one (1.6%) of 61 patients who had had preliminary myocardial revascularization.


Journal of Vascular Surgery | 1986

Peripheral artery and bypass graft thrombolysis with recombinant human tissue-type plasminogen activator

Robert A. Graor; Barbara Risius; Jess R. Young; Kevin M. Denny; Edwin G. Beven; Michael A. Geisinger; Norman R. Hertzer; Leonard P. Krajewski; Fred V. Lucas; Patrick J. O'Hara; William F. Ruschhaupt; Sheila Winton; Margaret G. Zelch; Grossbard Eb

Recombinant tissue-type plasminogen activator (t-PA) is a DNA-synthesized thrombolytic agent recently approved for clinical trials. We present the results of t-PA infusions in 18 patients with thrombosed peripheral arteries (12 patients) and peripheral bypass grafts (six patients). The duration of occlusion ranged from 1 to 21 days (mean, 6.8 days). Infusions of t-PA were done by way of an intra-arterial approach at a dose of 0.1 mg/kg/hr. All patients demonstrated thrombus lysis angiographically. Fifteen of 18 (83%) had clinical as well as angiographic improvement. Secondary procedures to maintain patency of the arterial segment were required in seven patients. No complications occurred that were related to the t-PA infusion. No significant prolongation of the prothrombin, thrombin, or activated partial thromboplastin times occurred. At the end of t-PA infusion, the mean circulating fibrinogen level was 59% of the starting value. The therapeutic use of t-PA is still in its preliminary stages and the efficacy and safety of this promising agent need to be further established. From our early experience with t-PA, it appears to be safe as well as effective.


Annals of Vascular Surgery | 1987

Late results of Coronary Bypass in Patients Presenting with Lower Extremity Ischemia: the Cleveland Clinic Study

Norman R. Hertzer; Jess R. Young; Edwin G. Beven; Patrick J. O'Hara; Robert A. Graor; William F. Ruschhaupt; Linda C. Maljovec

Cardiac catheterization was performed in a prospective series of 1000 patients under consideration for elective peripheral vascular reconstruction from 1978-1982. Of these, 381 (mean age 62) presented primarily because of lower extremity ischemia. Severe, surgically correctable coronary artery disease (CAD) was documented in 79 (21%) of the leg group, and 68 (18%) received myocardial revascularization, with three fatal complications (4.4%). In this subset, 39 patients have had uneventful aortoiliac, femoropopliteal or distal extremity procedures, compared to an operative mortality of 23% for 13 others with uncorrected or inoperable CAD (p = 0.015). A total of 286 patients have undergone 407 peripheral vascular operations with eight early deaths (2.8%). An additional 114 patients (30%) died during the late follow-up interval, including 48 (13%) with cardiac events. Both the cumulative 5-year survival (72%) and cardiac mortality (16%) after coronary bypass are superior to comparable figures (21% and 56%, respectively) among 36 other patients with severe, uncorrected or inoperable CAD (p = 0.0001). Five-year survival appears to be improved by myocardial revascularization in men (p = 0.0027), hypertensives (p = 0.0001), nondiabetics (p = 0.0002) and those over 60 years of age (p = 0.0072).


Pacing and Clinical Electrophysiology | 1984

Amaurosis Fugax in a Patient with a Left Ventricular Endocardial Pacemaker

William A. Schiavone; Lon W. Castle; Ernesto E. Salcedo; Robert A. Graor

A transvenous left ventricular endocardial pacemaker catheter is a potential source of systemic arterial embolization. The case of a woman who presented with left‐eye amaurosis fugax is reported. The patient had a history of contralateral carotid atherosclerosis; however, the digital subtraction angiography of the carotid arteries was not sufficiently abnormal to account for her present symptoms. The patient had a history of two myocardial infarctions and the tachycardia‐bradycardia syndrome for which she was treated with a demand ventricular pacemaker. The chest x‐ray and electrocardiogram suggested pacemaker catheter malposition. By M‐mode und two‐dimensional echocardiography, the catheter was shown to cross the atrial septum and the mitral valve to implant in the left ventricular endocardium. The approach to diagnosis and therapy that led to surgical removal of the pacing catheter is presented. The causes of the electrocardiographic right bundle branch block pattern in cardiac pacing and the usefulness of echocardiography in evaluating pacing catheters are discussed.


Journal of Vascular and Interventional Radiology | 1991

Relative Cost-Effectiveness of Urokinase versus Streptokinase in the Treatment of Peripheral Vascular Disease☆

Arina van Breda; Robert A. Graor; Barry T. Katzen; Barbara Risius; Dennis Gillings

A retrospective case control study of 271 patients with peripheral arterial occlusion (PAO) who were treated with urokinase (UK) or streptokinase (SK) at two clinical centers, Alexandria Hospital and the Cleveland Clinic, was performed. The primary objective was to evaluate the relative cost-effectiveness of thrombolytic therapy with SK or UK in the treatment of PAO. A secondary objective was to identify factors to which any major differences in cost-effectiveness between these two agents could be attributed. All available patients hospitalized at the two centers for PAO who underwent treatment with UK or SK from 1979 to 1987 were included. Therapeutic success was defined as complete clot lysis or partial clot lysis judged to be of clinical benefit by the attending physician, with no major bleeding or other serious complication such as renal insufficiency or death. Success rates with UK were higher than those with SK at both centers. The advantage with UK could not be explained by baseline patient characteristics. A cost-effectiveness ratio--dollars expended on medical care for up to 2 days after infusion per therapeutic success--was calculated for each of the treatments. Overall, at Alexandria Hospital,

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