Seymour Sprayregen

On the Nature and Etiology of Vascular Ectasias of the Colon: Degenerative lesions of aging

Vascular lesions of the right colon are being diagnosed increasingly as a cause of lower intestinal bleeding, but their nature and occurrence, primarily in the elderly, remains unexplained. Colons from patients with clinical and angiographic diagnoses of cecal vascular lesions were studied by injection and clearing, and by histological sections. In all injected specimens one or more mucosal vascular ectasias were identified. The mucosal lesions appeared to be secondary to dilated tortuous submucosal veins which were the more prominent feature and were often present without the mucosal ectasia. This suggests that ectasias are caused by chronic, intermittent, low grade obstruction to submucosal veins with dilation and tortuosity initially of submucosal veins, then of venules, capillaries, and arteries of the mucosal vascular unit. Ultimately, precapillary sphincters lose their competency, producing small arteriovenous communications. The concept that ectasias are degenerative lesions was evaluated by studying 15 right colons resected for carcinoma with no history of bleeding. Mucosal ectasias were identified in four colons and submucosal ectasias in eight. These investigations suggested that these lesions: (1) are vascular ectasias developing as a degenerative process of aging, (2) are present with or without bleeding in a significant portion of the population over 60 years of age, (3) are multiple more often than single, and (4) may represent the commonest cause of major lower intestinal bleeding in the elderly.

Changing arteriosclerotic disease patterns and management strategies in lower-limb-threatening ischemia.

From January 1, 1974 to December 31, 1989, we treated 2829 patients with critical lower-extremity ischemia. In the last 5 years, 13% of patients had therapeutically significant stenoses or occlusions above and below the groin, while 35% had them at two or three levels below the inguinal ligament. Unobstructed arterial flow to the distal half of the thigh was present in 26% of patients, and 16% had unobstructed flow to the upper third of the leg with occlusions of all three leg arteries distal to this point and reconstitution of some patent named artery in the lower leg or foot. In the last 2 years, 99% of all patients with a threatened limb and without severe organic mental syndrome or midfoot gangrene were amenable to revascularization by percutaneous transluminal angioplasty (PTA), arterial bypass, or a combination of the two, although some distal arteries used for bypass insertion were heavily diseased or isolated segments without an intact plantar arch. Limb salvage was achieved and maintained in more than 90% of recent patient cohorts, with a mean procedural mortality rate of 3.3%. Recent strategies that contributed to these results include (1) distal origin short vein grafts from the below-knee popliteal or tibial arteries to an ankle or foot artery (291 cases); (2) combined PTA and bypass (245 cases); (3) more distal PTA of popliteal and tibial artery stenoses (233 cases); (4) use of in situ or ectopic reversed autogenous vein for infrapopliteal bypasses, even when vein diameter was 3 to 4 mm; (5) composite-sequential femoropopliteal-distal (PTFE/vein) bypasses; (6) reintervention when a procedure thrombosed (637 cases) or was threatened by a hemodynamically significant inflow, outflow, or graft lesion (failing graft, 252 cases); (7) frequent follow-up to detect threatening lesions before graft thrombosis occurred and to permit correction of lesions by PTA (58%) or simple reoperation; and (8) unusual approaches to all infrainguinal arteries to facilitate secondary operations, despite scarring and infection. Primary major amputation rates decreased from 41% to 5% and total amputation rates decreased from 49% to 14%. Aggressive policies to save threatened limbs thus are supported.

Progress in limb salvage by reconstructive arterial surgery combined with new or improved adjunctive procedures.

In the past nine years, 1196 patients whose lower extremity was threatened because of infrainguinal arteriosclerosis have been treated at Montefiore Hospital. In the last six years, limb salvage was attempted in 679 or 90% of 755 patients. Femoro-popliteal (318), small vessel (204) and axillopopliteal (29) bypasses were used along with transluminal angioplasty (128) and aggressive local operations to obtain a healed foot. Immediate (one month) limb salvage was achieved in 583 or 86% of the 679 patients in whom revascularization was possible. The 30-day mortality rate was 3%. The cumulative life table (LT) survival rate of all the patients undergoing reconstructive arterial operations was 48% at five years. The cumulative LT limb salvage rate after all reconstructive arterial operations was 66% at five years. The cumulative LT patency rate of femoropopliteal bypasses was not influenced by angiographic outflow characteristics of the popliteal artery but was increased 15% by appropriate reoperations to 67% at five years. Cumulative LT patency and limb salvage rates of small vessel and axillopopliteal bypasses were more than 50% at two years. Of patients undergoing arterial reconstruction, 88% of those who died within five years did so without losing their limbs. Of all the patients in whom limb salvage was attempted, 68% lived more than one year with a viable, useable extremity, and 54% lived over two years with an intact limb. We believe this aggressive approach to limb salvage is justified, and can be undertaken with a low cost in mortality, knee loss and morbidity

Hypogastric artery coil embolization prior to endoluminal repair of aneurysms and fistulas: buttock claudication, a recognized but possibly preventable complication.

PURPOSE Hypogastric artery embolization is considered to be necessary to prevent retrograde flow and potential endoleaks when a stent-graft crosses the origin of the hypogastric artery. The authors assess the incidence of buttock claudication, which is the primary complication encountered. The effect of coil location and the presence of antegrade flow at the completion of embolization are evaluated. MATERIALS AND METHODS Hypogastric artery embolization and endoluminal repair of aneurysms and fistulas was performed in 34 patients (30 men; four women) aged 27-91 years (mean, 76 years). Ten patients were being treated for solitary abdominal aortic aneurysms, 13 were being treated for aortoiliac aneurysms, and six patients were being treated for isolated common iliac aneurysms, three for hypogastric artery aneurysms and two for iliac arteriovenous fistulas. Eleven patients had coils placed completely above the bifurcation of the hypogastric artery and 23 patients had coils placed at the bifurcation, or within the branches of the hypogastric artery. Preservation of antegrade flow after embolization was noted in 14 of 34 patients. RESULTS Thirty-four patients underwent stent-graft repair after hypogastric artery embolization. There were two perioperative deaths, three proximal leaks, and one collateral leak. Of the 32 patients who survived the procedure, there was one retrograde leak, even though 13 of 32 (41%) patients had continued antegrade flow at completion of the hypogastric artery embolization. When coils were placed at or in the bifurcation of the hypogastric artery, 12 of 22 (55%) experienced claudication. When coils were placed in the proximal hypogastric artery, one of 10 (10%) claudicated. CONCLUSION It is probably not necessary to completely occlude antegrade flow in the hypogastric artery to prevent a distal endoleak. Buttock claudication is rare when coils are placed in the proximal hypogastric artery rather than at its bifurcation or in its branches.

Angiographic diagnosis of mesenteric arterial vasoconstriction

Experimental mesenteric arterial vasoconstriction (MAV) is characterized by narrowings at the origins of multiple branches of the superior mesenteric artery, irregularities in intestinal branches, spasm of arcades, and impaired filling of intramural vessels. None of these findings occurred in a control group of patients without MAV. MAV may be diffuse or localized and reversible or irreversible. Reversible MAV decreases after test infusion of papaverine, and responds to therapeutic infusion of 30–60 mg of papaverine per hour for 16–24 hours. Several case studies are presented. Early diagnosis of reversible MAV is important to prevent irreversible bowel changes.

The Pathophysiologic Basis for the Angiographic Signs of Vascular Ectasias of the Colon

Three reliable diagnostic signs were identified on angiograms from 25 patients with ectasias of the right colon: (a) a slowly emptying dilated, tortuous, intramural vein; (b) a vascular tuft; and (c) an early filling vein. The frequency of these signs and the order of their occurrence reflect the different stages in the evolution of ectasias. The earliest and most frequent sign, the slowly emptying vein, reflects ectatic changes in a submocosal vein resulting from chronic intermittent partial obstruction. The vascular tuft represents more advanced lesions and corresponds to extension of the degenerative process to the venules in the mucosa. An early filling vein reflects an arteriovenous communication through a dilated arteriolar-capillary-venular unit-a mucosal ectasia.

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)

Tibiotibial vein bypass grafts: A new operation for limb salvage

Tibiotibial bypasses were performed with short (8 to 33 cm) segments of reversed autologous vein in 14 patients who did not have longer segments of usable vein. All patients faced imminent amputation unless they had an effective revascularization. Two patients died, one within 1 month of operation. One patient required below-knee amputation despite a patent bypass. Eleven patients (79%) have a patent bypass and a functional limb 6 to 50 months after operation. These good patency results even with several grafts inserted into isolated segments of tibial arteries, some with incomplete plantar arches, suggest that these short vein grafts may be superior to other vein grafts. Tibiotibial bypasses may improve limb salvage results in otherwise difficult circumstances.

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.

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.