Exercise thallium scans: patterns of use and impact on management of patients with known or suspected coronary artery disease.

Physicians' ordering patterns and subjective assessments of the management impact of 345 exercise thallium studies at a tertiary care hospital were evaluated. Exercise thallium tests were ordered to obtain functional information (60%), to detect myocardial ischemia (29%), for routine follow-up (6%) and for screening for coronary artery disease (CAD) (5%). Exercise thallium testing was ordered instead of exercise electrocardiography alone because of an interest in assessing the size of an ischemic or infarcted area (37%), a belief that the exercise electrocardiogram was likely to be nondiagnostic (35%) or that exercise thallium was a better test (23%). In 20% of cases physicians said that thallium imaging results were helpful or pivotal in major management decisions, such as those regarding catheterization or surgery. In most cases, no further tests were ordered and antianginal therapy or activity prescription was changed after exercise thallium testing. Exercise thallium images also helped to stratify patients into low and high probability of CAD categories better than exercise electrocardiographic results alone did. Our data suggest that physicians are using exercise thallium testing to obtain functional information more often than simply to detect CAD and that physicians consider the test to be of considerable value.

Catheterization and angioplasty of the nonopacified peripheral autogenous vein bypass graft.

Nonopacified lower extremity vein bypass grafts may not be thrombosed. Catheterization of these grafts should be performed whenever possible. If graft patency is demonstrated, vein graft angioplasty may restore flow without fibrinolytic therapy. In two cases of nonthrombosed nonopacified grafts, graft patency was demonstrated by catheterization of the grafts, and normal blood flow was restored by percutaneous transluminal angioplasty.

Radiologic evaluation of penile arterial anatomy in arteriogenic impotence.

Functional and anatomic evaluation of penile arterial blood flow is essential in the work up of erectile dysfunction. Duplex ultrasonography is an ideal screening modality with cavernosal mean peak systolic blood flow velocity being the most sensitive predictor of arterial disease. Arterial variability of the penis may affect sonographic evaluation leading to frequent misinterpretation and therefore pudendal arteriography remains the current gold standard for penile arterial evaluation. Appreciation of the type and frequency of anatomic variants and potential collateral routes is important in interpreting penile arteriograms and in evaluating the hemodynamic significance of suspected arterial disease.

Transfemoral endovascular stented graft treatment of aorto-iliac and femoropopliteal occlusive disease for limb salvage.

BACKGROUND: Endovascular stented grafts employ a new technique that blends intravascular stent and prosthetic graft technologies. These devices may be used to treat arterial aneurysms, occlusive disease, and vascular injuries. This report describes the application of stented grafts to the treatment of limb-threatening ischemia secondary to occlusive disease of the aorta, iliac, and femoral arteries. METHODS: Three patients with limb-threatening ischemia and severe comorbid medical illnesses were treated with transvascular stented grafts that were composed of 6-mm thin-walled polytetrafluoroethylene grafts and Palmaz balloon expandable stents. The grafts were inserted through a cutdown in an artery remote from the site of occlusion and introduced into the vascular system within 14-Fr introducer sheaths. RESULTS: Technical success was documented in all three patients with restoration of arterial continuity following stent graft deployment. Patency and limb salvage has been achieved to 1 year. One patient required further dilatation of the proximal stent at 6 weeks. Complications were limited to an iliofemoral deep vein thrombosis in one patient. CONCLUSIONS: Endovascular stented grafts can be inserted to treat limb-threatening ischemia. Although these initial results are encouraging, greater experience in more patients observed for longer periods of time is necessary before this technique can be advocated for widespread use.

Radiology in intestinal ischemia. Angiographic diagnosis and management.

Angiography is an essential component of the diagnosis and treatment of patients with acute and chronic intestinal ischemia. Aortography and selective angiography permit identification of the cause and precise anatomy of intestinal ischemic syndromes, and also help plan their potential correction. Direct intra-arterial infusion of pharmacologic agents into splanchnic vessels has now become part of the therapy of these conditions. This article reviews angiographic techniques and their applications in the management of intestinal ischemic syndromes.

Radiology in intestinal ischemia. Plain film, contrast, and other imaging studies.

Because plain films are usually normal or nonspecific in both colonic and acute mesenteric ischemia, they are not diagnostically helpful. The barium enema is the most useful radiographic examination in the diagnosis of colonic ischemia, and a double-contrast study will show abnormalities in almost all cases. Findings specific for colonic ischemia characteristically change with time. Thumbprinting is the most diagnostic finding; it is seen early in the course of the disease and usually resolves or is replaced within 1 or 2 weeks by an acute ulcerating colitis pattern. The latter may heal over months or go on to stricture formation or a persistent colitis. Nonspecific abnormalities can also be identified on CT and ultrasound, but the incidence of the findings with colonic ischemia is not known. Plain film findings occur late in the course of acute mesenteric ischemia and thus cannot be relied on for the diagnosis, although they may be useful in excluding other conditions. When acute mesenteric ischemia is suspected, angiography should be performed, but CT, ultrasound, and, perhaps, MR imaging may contribute to the diagnosis.

Endovascular stented graft repair of a pseudoaneurysm of the subclavian artery caused by percutaneous internal jugular vein cannulation: case report.

In high-risk patients endovascular repair of a pseudoaneurysm with a stented graft is a safe and reasonable treatment option that can preclude significant morbidity and shorten hospital stay. We report a case of pseudoaneurysm of the subclavian artery after internal jugular vein cannulation that was treated successfully with an endovascularly inserted, stented graft. The case report highlights the importance of recognizing this unusual but serious complication of percutaneous internal jugular vein catheterization through careful clinical examination, prompt duplex scanning, and arteriography.

Initial experience with the "Smart" laser in the treatment of atherosclerotic occlusions.

A dual laser system capable of distinguishing atherosclerotic plaque from components of normal arterial wall was used to deliver laser energy to cut a channel through occluded vessels. This system was used to facilitate balloon angioplasty of short (3-17 cm) total occlusions of the superficial femoral or popliteal arteries in 17 patients. In 10 patients the occluding lesion was traversed by the laser wire and patency was effectively restored by balloon angioplasty. Satisfactory luminal patency has persisted for 2 to 12 months (mean 6 months) in 9 cases; the lesion in the tenth patient restenosed at 3 months. The laser procedure was unsuccessful in all 3 cases with occlusions over 10 cm and in 4 others. There were no clinically important complications. This experience suggests that most patients who presently require interventional treatment can be managed by standard angioplasty methods and/or require a bypass operation. The "Smart" laser is safe and effective short-term in facilitating angioplasty in some patients in whom standard angioplasty techniques are not feasible. The implications of these findings are discussed.

Compression of vein graft by hematoma during fibrinolytic therapy simulating intrinsic venous stricture--a case report.

Narrowing of a vein graft at an area of perigraft extravasation was encountered during fibrinolytic therapy for graft thrombosis. With cessation of fibrinolytic therapy, extravasation ceased and the vein lumen widened. Extrinsic compression and/or spasm due to a hematoma should be included as causes of vein graft narrowing in patients undergoing fibrinolytic therapy.

Infrapopliteal percutaneous transluminal angioplasty: what we know.

We believe that a substantial experience demonstrating the effectiveness and safety of infrapopliteal artery PTA has been accumulated. It is clear that the results of tibial PTA and femoropopliteal PTA are closely associated for most patients undergoing limb salvage procedures. Anatomic selection is most important; patients with focal disease and restorable runoff will generally benefit, and interventional radiologists should concentrate on treating this group of patients. PTA and surgery for limb salvage patients are indeed complementary procedures, and patients will benefit most by a methodical team approach to treatment. Problems with reporting of data in the literature have obscured the true effectiveness of distal PTA, with such deficiencies leading to both overestimation and underestimation of clinical utility. Nevertheless, the preponderance of evidence (as we see it) suggests a clinical effectiveness of about 80% at 2 years in appropriately selected patients. Like Dr. Fraser and his co-authors, we would welcome randomized trials of tibial PTA versus surgery, but even in the absence of these, the reporting of indications and results needs to be standardized: severity of symptoms at presentation and the extent of conservative treatments employed before intervention; life-table methodology on an intent-to-treat basis with clear delineation of end points; stratification by important variables such as lesion length, runoff status, extent of preexisting tissue loss, presence of diabetes and ESRD, and ideally, functional outcome and quality-of-life measures. Finally, we should learn from our surgical colleagues that close surveillance and early reintervention will probably increase the effectiveness of our percutaneous treatment methods.

Percutaneous transluminal angioplasty of the infrapopliteal arteries: results in 53 patients.

Recent reports suggest that percutaneous transluminal angioplasty is a satisfactory alternative to surgical treatment of occlusion of the infrapopliteal arteries. To evaluate further the merits of percutaneous angioplasty of these vessels, we retrospectively analyzed the results of 57 procedures in 53 patients. Seventy-six infrapopliteal arteries were dilated: 26 anterior tibial arteries, 10 posterior tibial arteries, 18 peroneal arteries, and 22 tibioperoneal trunks. Thirty-three (62%) of the patients had concomitant angioplasties of the femoropopliteal arteries or vein grafts. There were three major complications (one death due to cardiac arrest 5 hr after the procedure and two puncture-site hematomas requiring surgery). Twenty minor complications did not affect clinical course. In the first 14 procedures (25%), tapered catheters were used, and technical success occurred in only four (29%). In the succeeding 43 procedures (75%), Gruentzig balloon catheters and low-profile balloons were used, and technical success occurred in 37 procedures (86%). Prompt clinical improvement was seen in 32 (80%) of 40 technically successful procedures. Prompt clinical improvement occurred in 28 (97%) of 29 procedures in which angioplasty restored straight-line flow to the foot (i.e., nonobstructed blood flow in at least one calf vessel that is narrowed by no more than 75% of its diameter). When such flow was not restored, clinical improvement occurred in only four (36%) of 11 cases (p less than .001). These results show that with current technology, infrapopliteal artery angioplasty is an effective and safe procedure. The greatest benefit is achieved when straight-line blood flow to the foot is restored.

Value of preoperative renal artery embolization in reducing blood transfusion requirements during nephrectomy for renal cell carcinoma.

PURPOSE: The authors evaluated the effectiveness of preoperative ethanol renal artery embolization in reducing transfusion requirements during nephrectomy for renal cell carcinoma. PATIENTS AND METHODS: Of 93 consecutive patients who underwent nephrectomy for renal cell carcinoma from 1980 to 1990, 24 patients underwent embolization within 24 hours of nephrectomy. Finding in this group were compared with those in 69 control patients who underwent surgery without preoperative embolization. RESULTS: Embolized tumors were larger than nonembolized ones (mean volume, 595 vs 257 mL) (P < .05). Patients with large hypervascular tumors (volume over 250 mL) who underwent complete embolization received significantly smaller mean blood transfusion volumes than control patients (250 vs 800 mL; P = .01). The transfusion volume associated with incomplete embolization was higher than that associated with no embolization. CONCLUSION: Complete alcohol embolization significantly reduces the volume of blood transfused during nephrectomy for large hypervascular renal cell carcinomas, and incomplete embolization is associated with larger transfusions. Preoperative embolization must be complete and should be performed more widely.

Delayed high flow priapism: pathophysiology and management.

Two cases of the management and pathophysiology of high flow arterial priapism are presented. Both cases were post-traumatic with delayed onset of priapism and both had angiographically diagnosed arteriocorporeal fistulas. Case 1 was managed with selective cavernous artery ligation and case 2 resolved spontaneously, both with excellent return of premorbid levels of erectile function. We propose that the pathophysiological mechanism involves injury to the intracavernous artery, causing ischemic necrosis. After a delay the arterial segment blows out, leading to unregulated blood flow into the corpus cavernosum. Management with surgical ligation is highly selective and nondisruptive to unaffected vessels, offering precise control of the bleeding vessel.

Short vein grafts: a superior option for arterial reconstructions to poor or compromised outflow tracts?

To determine whether vein graft length is a factor that influences infrapopliteal bypass patency, we reviewed 237 consecutive reversed saphenous vein bypasses performed because of critical ischemia during a 5-year period. One hundred seventeen long vein grafts (LVGs) were longer than 40 cm (42 to 92 cm, mean 60.9 +/- 9 cm) and 120 short vein grafts (SVGs) were 40 cm or shorter (6 to 40 cm, mean 24.7 +/- 8 cm). Ninety-three percent of the LVGs originated from or were proximal to the superficial femoral artery (SFA) whereas all of the SVGs originated at or distal to the SFA. The cumulative patency rate for LVGs at 3 years was 45% and for SVGs was 63% (p less than 0.025). In the absence of an intact pedal arch, 3-year patency rates for LVGs (51 cases) and SVGs (78 cases) were 22% and 53%, respectively (p less than 0.01). High intraoperative outflow resistance measurements (greater than 0.7 mm Hg/ml/min) were encountered in 25 cases. Of these, occlusion within 6 months occurred in six of seven cases with LVGs and in only 8 of 18 cases with SVGs (p less than 0.05). Wound complications at vein harvest sites occurred in 17% of LVGs and in only 6% of SVGs (p less than 0.01). Of 16 additional cases in which a proximal patch angioplasty or percutaneous transluminal angioplasty was performed tandem with a short distal vein graft, four occluded (less than 6 months) and 12 remained patent from 3 to 43 months (mean 12.6 months).(ABSTRACT TRUNCATED AT 250 WORDS)

Impact of nonoperative therapy on the clinical management of peripheral arterial disease.

Nonoperative therapy includes conservative noninterventional modalities and the endovascular interventional modalities of percutaneous transluminal angioplasty and a variety of laser systems and atherectomy devices. The role and impact of all nonoperative treatments are considered in the perspectives of the natural history of lower-extremity arteriosclerosis and its present surgical (operative) treatment. Nonoperative treatments may replace and/or facilitate surgical treatment in operative candidates. Nonoperative methods may also justify treatment in patients who cannot or should not be subjected to surgery. Facts and opinions relating to these uses of nonoperative treatments are presented, and the qualifications and credentialing of individuals who should be treating patients with lower-extremity ischemia resulting from peripheral arteriosclerosis are discussed.

Endoluminal therapy with endovascular grafts.

The addition of balloon-expandable stents to conventional graft material allows minimally invasive repair of aortic and other aneurysms, arterial occlusions, and arterial trauma. Vascular access can be made at a site far from the pathology.

Translumbar arch aortography: a retrospective controlled study of usefulness, technique, and safety.

Subclavian and axillary artery stenoses may lead to axillofemoral bypass graft failure. These arteries were assessed preoperatively with arch aortography performed after conventional high translumbar peripheral aortography by exchanging the initial 16-gauge sheath for a 5-F pigtail catheter. Thirty-two diagnostic translumbar runoff and arch (TLR-arch) aortograms were obtained in 30 patients with advanced lower extremity ischemia. In six patients (20%), the results of the arch study influenced the choice of an inflow site. These patients were compared with 70 control subjects who underwent conventional translumbar aortography without arch studies. In the TLR-arch group, two major complications occurred in one patient, while in the control group 11 major complications occurred in 10 patients. One retroperitoneal hematoma occurred in the TLR-arch group; two occurred in the control group. The mean change in hematocrit for the TLR-arch group was -3.81% (-0.0381), and for the control group it was -4.17% (-0.0417). This difference was not statistically significant. Arch aortography is a valuable adjunct to the translumbar aortofemoral study. It can be simply performed without increasing the morbidity of the peripheral study.

Endovascular repair of abdominal aortic aneurysm: value of postoperative follow-up with helical CT.

OBJECTIVE: Transfemorally placed endoluminal grafts are currently being evaluated as an alternative to open surgery for the treatment of abdominal aortic aneurysms. We determined the value of helical CT for the follow-up of patients treated with this new procedure. The purposes of this study were to determine CT features of a technically successful procedure, detect complications, and compare findings on CT scans obtained 24-48 hr after insertion of the graft with findings on angiograms obtained at the end of the endovascular procedure. SUBJECTS AND METHODS: Seven patients with large abdominal aortic aneurysms had helical CT within 48 hr after transfemoral insertion of an endoluminal graft. Findings on these CT scans were compared with findings on digital completion angiograms obtained immediately after placement of the graft. Additional follow-up CT scans were obtained for up to 15 months (mean, 8 months). The size of the aneurysmal sac; completeness of perigraft thrombosis; and position, shape, and patency of the device were recorded. RESULTS: CT scans obtained 24-48 hr after placement of the grafts showed complete thrombosis of the aneurysmal sac in three patients and incomplete thrombosis with patent perigraft channels in the four remaining patients. Angiograms showed a patent perigraft channel in only one patient. Two of four initially patent channels subsequently closed, but one of them recurred. Of four thrombosed aneurysms, two decreased in size, and two were unchanged on later follow-up. Of three aneurysms associated with perigraft channels, two became enlarged and one was stable. On the basis of CT criteria, successful endovascular repair was shown in four (57%) of seven patients. CONCLUSION: Helical CT is a sensitive means of evaluating the efficacy of endoluminal grafts. Decreased or stable size of the aneurysmal sac without perigraft channels on late follow-up CT signifies technical success. Persistence or recurrence of perigraft channels is the most likely cause of later enlargement of an aneurysm and therefore suggests procedural failure. Helical CT was more sensitive than angiography for detection of perigraft channels that occurred soon after treatment.

Thrombolytic therapy with use of alteplase (rt-PA) in peripheral arterial occlusive disease: review of the clinical literature. The Advisory Panel.

PURPOSE: The clinical literature describing the use of alteplase in the treatment of peripheral arterial occlusive (PAO) disease is reviewed. MATERIALS AND METHODS: The literature database was acquired by a MEDLINE search using the Boolean keyword string: tissue plasminogen activator and/or rt-PA and peripheral not animal. A review was performed to identify the dose range of alteplase, technique of infusion, use of anticoagulation, clinical success rates, and risk of complications. RESULTS: Forty-six clinical studies were identified. There are few prospective, randomized clinical trials and a lack of standardized protocols and endpoints. Use of catheter-directed infusions of recombinant tissue plasminogen activator (rt-PA) may be beneficial versus surgery in the initial management of acute limb ischemia (< 14 days) and in reducing the magnitude of subsequent surgical or percutaneous revascularization. For patients with chronic limb ischemia (> 14 days), irreversible acute limb ischemia, or advanced diabetic arteriopathy, catheter-directed infusion of rt-PA or other plasminogen activators may be unsuitable. The risk of adverse bleeding appears related to the overall dose and duration of infusion. These risks appear similar to those of urokinase. The role of heparin in increasing adverse bleeding during rt-PA therapy is unclear. CONCLUSIONS: There is no generally accepted dose or technique for administering catheter-directed thrombolysis using alteplase; however, several studies have demonstrated its clinical safety and efficacy. Formal studies will be required to determine the optimal dose, technique of infusion, the role of anticoagulation, and complication rates when alteplase is used for PAO disease.