Further technical considerations of the sleeve microanastomosis

In sleeve anastomoses, stenoses at the suture site have been the main concern. Mechanical dilatation is one way to prevent the stenosis, as suggested by Lauritzen. In the present study, 50 vessels (femoral and carotid) and 10 veins were used for sleeve anastomoses and the same numbers of vessels were used for conventional anastomoses (as control) to evaluate the effect of mechanical dilatation using resin corrosion cast (Mercox) because the Mercox cast facilitates three-dimensional stereoscopic views. Gradual dilatations around the suture sites were observed in seven carotid arteries, and three of seven resulted into aneurysm formation due to weakening of the inner vascular wall in the sleeve anastomosis. No dilatation or aneurysm was observed in the femoral arteries. Newly proliferating capillaries formed on the endothelial surfaces of the inner vascular walls around the suture sites after 4 weeks in the sleeve anastomoses. Operative time and endothelial trauma were markedly reduced with sleeve anastomoses. The gradual dilatation and aneurysm formation in the carotid arteries show that sleeve anastomoses should be used carefully for high-pressure arteries in clinical practice if mechanical dilatation is performed.     

The False Aneurysm

The clinical course of 18 patients with 25 false aneurysms is reviewed. In recent years false aneurysm has been most commonly seen as a complication of arterioplastic procedures in which prosthetic arterial grafts were used. The use of indwelling needles or cannulae, particularly in patients with a wide arterial pulse pressure, can also lead to the formation of false aneurysms. In the groin, a false aneurysm is frequently mistaken for an abscess. Early diagnosis and operative repair are essential to reduce the incidence of further complications.     

Evidence for lipid peroxidation in atherosclerosis

Lipid peroxidation may play a significant role in the initiation and progression of atherosclerotic plaque. Freshly harvested normal and atherosclerotic human aortic tissue, coronary arteries and explanted vein grafts were snap frozen at -70 degrees C. Folch reagent (chloroform-methanol 2:1, v/v) was used to extract lipids from the homogenates. These extracts were assayed for cholesterol, phospholipid and triglyceride content. Lipid peroxide complexes in vessels were measured fluorometrically. Atherosclerotic plaque from patients with aortic aneurysmal and occlusive disease and coronary artery disease contained significantly greater amounts of cholesterol (15.54 +/- 9.71 vs 3.39 +/- 1.14 mg/g tissue) than controls (p less than 0.01). Lipid peroxide fluorochromes were similarly elevated in all atherosclerotic tissue (4.159 +/- 1.065 vs 3.087 +/- 0.497 fluoro units/g tissue) compared to control (p less than 0.01) with significant elevations in saphenous vein grafts and occlusive aortic disease. Although lipid peroxidation and lipid accumulation occur in close association in atherosclerotic plaque, the role of lipid peroxides in the pathogenesis of atherosclerosis remains to be determined.     

Gore-Tex small-vessel angioplasty: A suitable substitute for the use of autogenous saphenous vein grafts

Autogenous saphenous vein has been the material of choice for small-vessel angioplasty and for circulatory access graft reconstruction. In an effort to conserve autogenous saphenous vein, we used expanded polytetrafluoroethylene (PTFE) grafts in 45 patients over a 12-month period. We used Gore-Tex(*) to reconstruct 17 circulatory access grafts, 16 carotid arteries, two brachial arteries, seven femoral arteries, and three popliteal anterior or posterior tibial arteries. The indications for reconstruction were chronic occlusion of the access grafts, trauma to the brachial and anterior tibial arteries, and atherosclerotic disease of the carotid, femoral, and popliteal-tibial arteries. Of the reconstructed circulatory access grafts, one failed immediately because of technical problems in the conduit, and one failed 11 months after reconstruction. All other grafts have functioned well and have produced a marked improvement in flow. Of the 28 patients who underwent reconstruction of arteries measuring 3 mm or less, two had patent arteries but died shortly after operation. The remaining 26 have been followed for one to 43 months. All reconstructed arteries are patent, and there have been no instances of distal embolization or false aneurysm formation. From this brief experience, we conclude that Gore-Tex is a suitable short-term alternative to saphenous vein for small vessel arterioplasty; it also may be the material of choice for reconstructing the outflow tract of occluded access grafts.     

Analysis of blood flow behaviour in custom stent grafts

Endovascular aneurysm repair (EVAR) is an attractive alternative to open surgery for treating abdominal aortic aneurysms (AAAs). However, the implantation of stent grafts into AAAs can result in post-operative complications such as stent graft migration, rupture or endoleak. EVAR has therefore been carried out only on selected patients. Stent grafts are usually standard commercial stent grafts (CSGs); however, custom made stent grafts (cmSGs) of various shapes and sizes are sometimes used to fit patients’ anatomies. In the present study, the cmSGs were specially designed and fabricated by the surgeons at the Pitié-Salpétriére hospital in Paris. Two patients carrying cmSGs with unfavourable geometries showing tortuous shapes, angulation, widening, narrowing, curvature and kinking and one patient with a cmSG with a more favourable geometry resembling a straight tube were examined. These three clinical cases were investigated using three-dimensional numerical simulations, and the results showed that even when the cmSG geometries are unfavourable, the drag forces to which they are subjected are of a similar magnitude to those exerted on CSGs, or even smaller. The hemodynamic analysis carried out on the two unfavourable cmSGs showed the occurrence of low velocity values in the main trunk of the cmSGs, high velocities linked to recirculation areas downstream from kinking and strong distal narrowing. These flow patterns are liable to induce thrombus. However, since cmSG implantation can save the lives of patients for whom neither classical stent grafts nor open surgery are indicated, it can be concluded that these devices are useful in some cases.     

Extracellular Matrix Defects in Aneurysmal Fibulin-4 Mice Predispose to Lung Emphysema

Background

In this study we set out to investigate the clinically observed relationship between chronic obstructive pulmonary disease (COPD) and aortic aneurysms. We tested the hypothesis that an inherited deficiency of connective tissue might play a role in the combined development of pulmonary emphysema and vascular disease.

Methods

We first determined the prevalence of chronic obstructive pulmonary disease in a clinical cohort of aortic aneurysms patients and arterial occlusive disease patients. Subsequently, we used a combined approach comprising pathological, functional, molecular imaging, immunological and gene expression analysis to reveal the sequence of events that culminates in pulmonary emphysema in aneurysmal Fibulin-4 deficient (Fibulin-4^R) mice.

Results

Here we show that COPD is significantly more prevalent in aneurysm patients compared to arterial occlusive disease patients, independent of smoking, other clinical risk factors and inflammation. In addition, we demonstrate that aneurysmal Fibulin-4^R/R mice display severe developmental lung emphysema, whereas Fibulin-4^+/R mice acquire alveolar breakdown with age and upon infectious stress. This vicious circle is further exacerbated by the diminished antiprotease capacity of the lungs and ultimately results in the development of pulmonary emphysema.

Conclusions

Our experimental data identify genetic susceptibility to extracellular matrix degradation and secondary inflammation as the common mechanisms in both COPD and aneurysm formation.     

Campath-1 Abs 'in the bag' for hematological malignancies: the Cape Town experience

BACKGROUND: We examined the strategy of T-cell depletion of HLA-identical sibling grafts for the prevention of GvHD, as well as disease control and overall survival. PATIENTS AND METHODS: The myeloablative conditioning was radiation based. The source of stem cells was BM in 62, and cytokine-mobilized PBPC in 68 patients. GvHD prophylaxis was by ex vivo incubation of the stem-cell concentrates with Campath-1G (anti-CD52; n=76) or Campath-1H (n=54). RESULTS: Patients receiving PBPC grafts were older (median 38.5) than those undergoing BMT (median 31; P=0.002). More patients in the PBPC group developed chronic GvHD (p<0.01). While no post-transplant GvHD prophylaxis was given to BMT recipients, prednisone 30 mg daily was prescribed to 12 and CYA for 90 days to a further 32 patients who had received PBPC grafts. Median follow-up was 1055 (range 28-4867) days. Although there was no difference in the survival between patients who received BMT or PBPC, death was from disease recurrence in 16 and nine (p=0.03; chi(2) test) subjects, respectively. Multivariate analysis showed that outcome was particularly favorable in those who were given<20 mg Campath-1 (survival: 28/39 versus 12/29; P=0.01), and in the subgroup of 30 patients who received Campath-1H and post-transplantation CYA. DISCUSSION: In patients receiving BMT, Campath-1 Abs effectively prevent GvHD. For those treated with PBPC grafts, the combination of T-cell depletion and post-transplantation CYA is equally effective, without an obvious increase in disease recurrence.     

Protection of Renal Function During Surgery of the Abdominal Aorta

The operative and postoperative urinary output of 55 patients who underwent surgery for ruptured abdominal aortic aneurysms, unruptured abdominal aortic aneurysms, and aorto-iliac occlusive disease was recorded. There were five cases of postoperative anuria among 28 patients who received no free fluid in the immediate preoperative period. No case of anuria occurred in 27 patients who received either: (1) a water load of 5% dextrose in water or (2) 20% mannitol solution. The patients who received mannitol had a markedly greater operative and postoperative urinary output.Intravenous infusion of mannitol is recommended during the preoperative and operative period in patients with ruptured aneurysms of the abdominal aorta.     

介入栓塞治疗内脏动脉瘤的临床研究

目的:探讨介入血管腔内栓塞治疗内脏动脉瘤的方法、疗效及安全性。方法:选择内脏动脉瘤患者23例,包括脾动脉瘤13例,肝动脉瘤2例,胃十二指肠动脉瘤3例,肠系膜上动脉瘤4例,肾动脉瘤1例。其中,9例行远近端动脉栓塞术,4例采用支架辅助弹簧圈瘤体内填塞,3例采用弹簧圈瘤体内填塞加瘤体内注胶栓塞术,4例行弹簧圈瘤体内栓塞术,2例行分支动脉颗粒栓塞术,1例行单纯注胶栓塞术。术后1月、3月、6月行超声、CTA或血管造影复查,以后每年复查一次。结果:本组均成功行介入血管腔内栓塞治疗内脏动脉瘤,栓塞治疗后造影示动脉瘤体和/或载瘤动脉闭塞,动脉瘤体内无明显对比剂显影,脾动脉瘤栓塞患者有3例出现发热,脾区疼痛等脾梗塞症状,未见栓塞术相关严重并发症发生。4例消化道出血患者出血均停止。术后随访3~48个月,未见动脉瘤破裂出血、动脉瘤复发或增大,支架置入者,支架内及分支动脉血流均保持通畅。结论:介入血管腔内栓塞是一种治疗内脏动脉瘤的简便、微创、安全有效的方法。     

Full-thickness grafting of acute eyelid burns should not be considered taboo.

Split-thickness skin grafts are commonly used for the treatment of acute eyelid burns; in fact, this is dogma for the upper lid. Ectropion, corneal exposure, and repeated grafting are common sequelae, almost the rule. It was hypothesized that for acute eyelid burns, the use of full-thickness skin grafts, which contract less than split-thickness skin grafts, would result in a lower incidence of ectropion with less corneal exposure and fewer recurrences. The records of all patients (n = 18) who underwent primary skin grafting of acutely burned eyelids (n = 50) between 1985 and 1995 were analyzed retrospectively. There were 10 patients who received full-thickness skin grafts (12 upper lids, 8 lower lids) and 8 patients who received split-thickness skin grafts (15 upper lids, 15 lower lids). Three of 10 patients (30 percent) who received full-thickness skin grafts and 7 of 8 patients (88 percent) who received split-thickness skin grafts developed ectropion and required reconstruction of the lids (p = 0.02). No articles were found substantiating the concept that only split-thickness grafts be used for acute eyelid burns. The treatment of acute eyelid burns with full-thickness rather than split-thickness skin grafts results in less ectropion and fewer reconstructive procedures. It should no longer be considered taboo and should be carried out whenever possible and appropriate.     

Clinical course after corticosteroid therapy in IgG4-related aortitis/periaortitis and periarteritis: a retrospective multicenter study

Introduction

Immunoglobulin G4 (IgG4)–related aortitis/periaortitis and periarteritis are vascular manifestations of IgG4-related disease. In this disease, the affected aneurysmal lesion has been suspected to be at risk of rupture. In this study, we aimed to clarify the clinical course after corticosteroid therapy in IgG4-related aortitis/periaortitis and periarteritis.

Methods

We retrospectively evaluated clinical features, including laboratory data, imaging findings and the course after corticosteroid therapy, in 40 patients diagnosed with IgG4-related aortitis/periaortitis and periarteritis on the basis of periaortic/periarterial radiological findings, satisfaction of the comprehensive diagnostic criteria or each organ-specific diagnostic criteria, and exclusion of other diseases.

Results

The patients were mainly elderly, with an average age of 66.4 years and with a marked male predominance and extensive other organ involvement. Subjective symptoms were scanty, and only a small proportion had elevated serum C-reactive protein levels. The affected aorta/artery were the abdominal aortas or the iliac arteries in most cases. Thirty-six patients were treated with prednisolone, and the periaortic/periarterial lesions improved in most of them during the follow-up period. Two (50.0%) of four patients with luminal dilatation of the affected lesions before corticosteroid therapy had exacerbations of luminal dilatation after therapy, whereas none of the twenty-six patients without it had a new appearance of luminal dilatation after therapy.

Conclusions

The results of this retrospective multicenter study highlight three important points: (1) the possibility of latent existence and progression of periaortic/periarterial lesions, (2) the efficacy of corticosteroid therapy in preventing new aneurysm formation in patients without luminal dilatation of periaortic/periarterial lesions and (3) the possibility that a small proportion of patients may actually develop luminal dilatation of periaortic/periarterial lesions in IgG4-related aortitis/periaortitis and periarteritis. A larger-scale prospective study is required to confirm the efficacy and safety of corticosteroid therapy in patients with versus those without luminal dilatation and to devise a more useful and safe treatment strategy, including administration of other immunosuppressants.     

Transascending aortic intraaortic balloon insertion with delayed sternal closure: A retrospective analysis

Intraaortic balloon pumping (IABP) is an established therapeutic adjunct in the treatment of postcardiotomy/infarction low cardiac output states. Although the common femoral or iliac arteries are the preferred sites for balloon insertion, severe arterial occlusive disease may preclude entry by these methods. To circumvent this problem, alternative methods of insertion utilizing transthoracic approaches have evolved. In our institution, direct (transaortic) IABP insertion, combined with delayed sternal closure to avoid cardiac compression and possible tamponade, was performed in 28 adult postcardiotomy patients (mean age 60.4 +/- 3 years). The severity of generalized atherosclerosis was reflected in an overall survival rate of 28.6%. Retrospective analyses of the clinical courses of these patients revealed that the transaortic approach allowed utilization of larger and more effective balloons. Successful insertion of 30 and 40 ml balloons was accomplished in 27 of 28 (96%) of these patients, and one patient with a hypoplastic aorta required a 20 ml balloon. There were no complications directly attributable to this alternative site of balloon insertion, and tamponade was avoided. Delayed sternal closure was accomplished within 48 to 96 hours. We concluded that when severe peripheral vascular occlusive disease prevents insertion of intraaortic balloons via the femoral or iliac arteries in patients with low cardiac output, the alternative transaortic approach is indicated. Combined with delayed sternal closure in patients with postcardiotomy dilatation, additional benefits accrue.     

Biomechanical behaviour of cerebral aneurysm and its relation with the formation of intraluminal thrombus: a patient-specific modelling study

Cerebral aneurysm is an irreversible dilatation causing intracranial haemorrhage with severe complications. It is assumed that the biomechanical factor plays a significant role in the development of cerebral aneurysm. However, reports on the correlations between the formation of intraluminal thrombus and the flow pattern, wall shear stress (WSS) distribution of the cerebral aneurysm as well as wall compliance are still limited. In this research, patient-specific numerical simulation was carried out for three cerebral aneurysms based on magnetic resonance imaging (MRI) data-sets. The interaction between pulsatile blood and aneurysm wall was taken into account. The biomechanical behaviour of cerebral aneurysm and its relation with the formation of intraluminal thrombus was studied systematically. The results of the numerical simulation indicated that the region of low blood flow velocity and the region of swirling recirculation were nearly coincident with each other. Besides, there was a significant correlation between the slow swirling flow and the location of thrombus deposition. Excessively low WSS was also found to have strong association with the regions of thrombus formation. Moreover, the relationship between cerebral aneurysm compliance and thrombus deposition was discovered. The patient-specific modelling study based on fluid–structure interaction) may provide a basis for future investigation on the prediction of thrombus formation in cerebral aneurysm.     

Combined replacement of the ascending aorta and the aortic valve in 42 consecutive patients: A comparison of composite graft techniques and conventional techniques over one year

During 1978, 42 consecutive patients underwent simultaneous aortic valve and ascending aorta replacement in our institution. Seventy-one percent were at low risk despite a high incidence of dissection. Twenty-nine percent were high-risk patients requiring repeat or concomitant cardiac procedures, mostly on an emergency basis. Depending upon the extent of the disease at the aortic root, either of two surgical approaches was used: (1) conventional aortic valve and supracoronary ascending aorta replacement, with or without right coronary artery ostium reimplantation, or (2) insertion of a composite graft containing an aortic valve prosthesis, with reconstruction of both coronary arteries. Preservation of coronary ostia was possible in 85% of the patients, and composite grafts were used in 15%. The conventional method was associated with a higher percentage of survivors. This technique was found to be satisfactory unless severe dilatation or complete destruction of the aortic annulus made composite grafting necessary. The latter technique was associated with fewer re-explorations for postoperative hemorrhage. Both procedures were equally effective, resulting in an operative mortality of 10% in uncomplicated situations. Surgery appeared to offer the only chance of survival for the high-risk group, and half of these patients were salvaged.     

Dorsal dermis development depends on a signal from the dorsal neural tube, which can be substituted by Wnt-1

To investigate the origin and nature of the signals responsible for specification of the dermatomal lineage, excised axial organs in 2-day-old chick embryos were replaced by grafts of the dorsal neural tube, or the ventral neural tube plus the notochord, or aggregates of cells engineered to produce Sonic hedgehog (Shh), Noggin, BMP-2, Wnt-1, or Wnt-3a. By E10, grafts of the ventral neural tube plus notochord or of cells producing Shh led to differentiation of cartilage and muscles, and an impaired dermis derived from already segmented somites. In contrast, grafts of the dorsal neural tube, or of cells producing Wnt-1, triggered the formation of a feather-inducing dermis. These results show that the dermatome inducer is produced by the dorsal neural tube. The signal can be Wnt-1 itself, or can be mediated, or at least mimicked by Wnt-1.     

Formation of 13,14-dihydro-prostaglandin E1 during intravenous infusions of prostaglandin E1 in patients with peripheral arterial occlusive disease.

Formation of 13,14-dihydro-prostaglandin (PG) E1 during intravenous infusions of PGE1 in patients with peripheral arterial occlusive disease was investigated. Using both high performance liquid chromatography (h.p.l.c.) combined with radioimmunoassay and gas chromatography/triple stage quadrupole mass spectrometry (GC/MS/MS) basal levels of 13,14-dihydro-PGE1 were found to be close to or below the detection limits of the assay methods. Levels of the PGE1 metabolite increased significantly during the infusion periods and decreased after their end. Since 13,14-dihydro-PGE1, in contrast to its precursors 15-keto-PGE1 and 15-keto-13,14-dihydro-PGE1, is biologically active, its formation could contribute to the beneficial effects of PGE1 administered intravenously in patients with peripheral arterial occlusive disease.     

Low dose computerized tomography examinations of coronary occlusive disease

Background: The aim of this study was to present an original technique of low-dose coronary computerized tomographyangiography (CCTA) for the evaluation and early diagnosis of coronary occlusive disease (COD) and to compare from this technique of CCTA with those resulting from the latest conventional angiography and multidetector computerized tomography units. Methodology: The study included 820 CCTA exams of patients with COD (average age 61 +/? 7 years), with a follow-up exam in 204 male (39%) and 62 female (20%) patients with hemodynamically insignificant coronary occlusion. Exams were performed using a 64-slice computerized tomography (CT) unit using electrocardiography (ECG)-triggering and individual settings (voltage of the x-ray tube and effective tube-current) based on each patient’s body mass index. Exponential dose for each exam was defined. Results:There was a statistically significant progression in the number of patients in whom occlusion of one of 3 coronary arteries occurred in hemodynamically significant occlusive disease (occlusion of more than 50% of lumen) — 60 of 204 males and 12 of 62 females (p<0.0001 and p<0.001). The mid-effective radiation dose during CCTA exams was 1.9+/-0.7mSv (range of 0.9 to 3.9 mSv). Conclusion: Prospective ECG-triggering allowed for low-dose CCTA exams while still enabling high diagnostic accuracy in evaluating patients with COD. The technique used in this study resulted in 2 times less the exponential dose than conventional angiography.     

On the metabolism of prostaglandin E1 administered intravenously to human volunteers.

We have demonstrated recently the formation of a biologically active metabolite of prostaglandin (PG) E1, 13,14-dihydro-PGE1, during intravenous infusions of PGE1 in patients with peripheral arterial occlusive disease. We have now investigated the levels of the immediate precursor of 13,14-dihydro-PGE1, the biologically inactive 15-keto-13,14-dihydro-PGE1, during intravenous administration of 20 micrograms, 40 micrograms or 80 micrograms PGE1 over a period of 60 min to human volunteers. It was found that levels of 15-keto-13,14-dihydro-PGE1, but not those of PGE1 itself, increased in a dose-dependent manner. Thus, increased formation of 13,14-dihydro-PGE1 from 15-keto-13,14-dihydro-PGE1 with increasing doses of PGE1 can be expected to occur. It remains to be investigated, to which extent formation of small amounts of 13,14-dihydro-PGE1 during intravenous infusion of PGE1 could contribute to the therapeutic effects of PGE1 in patients with peripheral arterial occlusive disease.     

Assessment of Reconstructive Procedures for Femoropopliteal Artery Occlusive Disease

A total of 117 consecutive reconstructive procedures for femoropopliteal arterial occlusive disease in 105 extremities of 101 patients have been reviewed. The types of procedures included 10 homografts, 28 Dacron and Teflon prosthetic grafts, 16 thromboendarterectomies and 63 vein bypass grafts. There were three postoperative deaths.The results of autogenous vein bypass grafts, as indicated by an early success rate of 90% and late patency rate of 76%, are superior to those obtained by other methods of reconstruction in the institution where this study was made.Early failure of these grafts in most instances relates to technical errors which can be reduced by meticulous surgical technique, operative angiography and close postoperative follow-up with early correction.Some of the late failures can be attributed to stenosis of the graft rather than to the progressive nature of the arteriosclerotic disease. Repeated followup examinations of the extremity at regular intervals and early angiography in the patients with return of symptoms may allow correction of the graft defect and salvage of the extremity.