The endovascular management of blue finger syndrome. (1/776)

OBJECTIVES: To review our experience of the endovascular management of upper limb embolisation secondary to an ipsilateral proximal arterial lesion. DESIGN: A retrospective study. MATERIALS AND METHODS: Over 3 years, 17 patients presented with blue fingers secondary to an ipsilateral proximal vascular lesion. These have been managed using transluminal angioplasty (14) and arterial stenting (five), combined with embolectomy (two) and anticoagulation (three)/anti-platelet therapy (14). RESULTS: All the patients were treated successfully. There have been no further symptomatic embolic episodes originating from any of the treated lesions, and no surgical amputations. Complications were associated with the use of brachial arteriotomy for vascular access. CONCLUSIONS: Endovascular techniques are safe and effective in the management of upper limb embolic phenomena associated with an ipsilateral proximal focal vascular lesion.  (+info)

Thromboatheromatous complications of umbilical arterial catheterization in the newborn period. Clinicopathological study. (2/776)

Severe catheter-related thromboatheromatous lesions were found at necropsy in 33 of 56 infants who had umbilical arterial catheters passed during life. In infants dying within 8 days of insertion of the catheter, varying degrees of thrombosis of the aorta and its major branches were seen. With increasing thrombosis and aging of the thrombus, fatty deposits were seen first within the thrombus, and then in the intima and media. In addition there was evidence of proliferation of medial smooth muscle cells and of disruption of the medial architecture below the thrombus, characterized by the presence of abundant mucopolysaccharide. In infants who survived longer, varying degrees of organization of the thrombus could be traced, leading eventually to raised fibrous plaques with lipid and occasionally calcification. The lesions in the older infants were similar in many respects to experimental thromboatheromatous lesions produced in rabbits, and to some lesions of artheroma occurring spontaneously in humans. A wide variety of embolic phenomena were found, with features suggesting asynchrony of embolic episodes. The presence of thrombotic lesions could not be related to birthweight, Apgar scores at 1 and 5 minutes, age at catheterization, duration of catheterization, underlying disease process, age at death or the presence of hypothermia, acidosis, or anomalies in coagulation tests. There is a need for less hazardous methods of monitoring arterial oxygen tension.  (+info)

Mechanisms of retarded apical filling in acute ischemic left ventricular failure. (3/776)

BACKGROUND: We examined the hypothesis that retardation of apical filling as measured by color M-mode Doppler echocardiography in the diseased left ventricle (LV) reflects a decrease in the intraventricular mitral-to-apical pressure gradient. METHODS AND RESULTS: In 9 open-chest anesthetized dogs, micromanometers were placed near the mitral tip and in the apical region. From the color M-mode Doppler images, the time delay (TD) between peak velocity at the mitral tip and the apical region was determined as an index of LV flow propagation. Acute ischemic LV failure was induced by coronary microembolization. Induction of ischemia caused a marked increase in LV end-diastolic pressure and a decrease in LV ejection fraction. The time constant of LV isovolumic apical pressure decay (tau) increased from 31+/-8 to 49+/-16 ms (P<0.001). The peak early diastolic mitral-to-apical pressure gradient (DeltaPLVmitral-apex) decreased from 1.9+/-0.9 to 0.7+/-0.5 mm Hg (P<0.01), and TD increased from 5+/-3 to 57+/-26 ms (P<0.001). The slowing of flow propagation was limited to the apical portion of the LV cavity. The TD correlated with DeltaPLVmitral-apex (r=-0.94, P<0.01) and with tau (r=0.92, P<0.01). Before ischemia, the mitral-to-apical flow propagation velocity far exceeded the velocity of the individual blood cells, whereas during ischemia, flow propagation velocity approximated the blood velocity. CONCLUSIONS: Retardation of apical filling in acute ischemic failure was attributed to a decrease in the mitral-to-apical driving pressure, reflecting slowing of LV relaxation. The slowing of flow propagation appeared to represent a shift in apical filling from a pattern of column motion to a pattern dominated by convection.  (+info)

Should initial clamping for abdominal aortic aneurysm repair be proximal or distal to minimise embolisation? (4/776)

OBJECTIVES: to determine whether clamping proximally or distally on the infrarenal aorta during abdominal aortic aneurysm (AAA) repair increases the overall embolic potential. MATERIALS AND METHODS: a sheath was placed in the mid-infrarenal aorta of 16 dogs. In eight animals a cross-clamp was placed at the aortic trifurcation, and in another eight animals it was placed in the immediate subrenal position. Under fluoroscopy blood flow within the infrarenal aorta was evaluated by contrast and particle injections. Grey-scale analysis was used to calculate contrast density. Particle distribution was followed fluoroscopically and confirmed pathologically. RESULTS: fifty-seven+/-24% of injected contrast remained within the aorta with distal clamping while 97+/-7% did so with proximal clamping (p<0.01). With distal aortic clamping 6.2+/-1. 3 out of 10 injected particles remained within the aorta after 15 seconds and only 0.8+/-0.8 remained after 5 min. With proximal aortic clamping, all 10 of the particles remained within the aortic lumen for the full 5 minutes (p<0.001). CONCLUSIONS: initial distal clamping minimises distal embolisation, but may result in renal and/or visceral embolisation. Initial proximal clamping prevents proximal embolisation and does not promote distal embolisation. We recommend initial proximal clamping in aortic aneurysm surgery to minimise the overall risk of embolisation.  (+info)

Atrial fibrillation in general practice: how useful is echocardiography in selection of suitable patients for anticoagulation? (5/776)

All patients identified from records in two practices in West Lothian (n = 103) as having atrial fibrillation (AF) were offered a clinical examination, electrocardiogram (ECG), and echocardiography. Sixty-five patients attended the examinations. Of these, 26 (40%) were found to be in sinus rhythm. Many of those in AF were already on warfarin. Only eight who were found to have AF, who were not already on warfarin and who had no contraindications to it, had additional risk factors that suggested they be treated with warfarin. In no case did echocardiography alter management decisions.  (+info)

Acetylsalicylic acid reduces vegetation bacterial density, hematogenous bacterial dissemination, and frequency of embolic events in experimental Staphylococcus aureus endocarditis through antiplatelet and antibacterial effects. (6/776)

BACKGROUND: Platelets are integral to cardiac vegetations that evolve in infectious endocarditis. It has been postulated that the antiplatelet aggregation effect of aspirin (ASA) might diminish vegetation evolution and embolic rates. METHODS AND RESULTS: Rabbits with Staphylococcus aureus endocarditis were given either no ASA (controls) or ASA at 4, 8, or 12 mg. kg-1. d-1 IV for 3 days beginning 1 day after infection. Vegetation weights and serial echocardiographic vegetation size, vegetation and kidney bacterial densities, and extent of renal embolization were evaluated. In addition, the effect of ASA on early S aureus adherence to sterile vegetations was assessed. In vitro, bacterial adherence to platelets, fibrin matrices, or fibrin-platelet matrices was quantified with either platelets exposed to ASA or S aureus preexposed to salicylic acid (SAL). ASA at 8 mg. kg-1. d-1 (but not at 4 or 12 mg. kg-1. d-1) was associated with substantial decreases in vegetation weight (P<0.05), echocardiographic vegetation growth (P<0.001), vegetation (P<0.05) and renal bacterial densities and renal embolic lesions (P<0.05) versus controls. Diminished aggregation resulted when platelets were preexposed to ASA or when S aureus was preexposed to SAL (P<0.05). S aureus adherence to sterile vegetations (P<0.05) or to platelets in suspension (P<0.05), fibrin matrices (P<0.05), or fibrin-platelet matrices (P<0.05) was significantly reduced when bacteria were preexposed to SAL. CONCLUSIONS: ASA reduces several principal indicators of severity and metastatic events in experimental S aureus endocarditis. These benefits involve ASA effects on both the platelet and the microbe.  (+info)

Prevention of distal embolization during saphenous vein graft lesion angioplasty. Experience with a new temporary occlusion and aspiration system. (7/776)

BACKGROUND: Repeat coronary artery bypass graft surgery (CABG) is associated with a high morbidity and mortality, rendering percutaneous treatment of saphenous vein graft (SVG) lesions an attractive alternative. However, percutaneous interventions of degenerated SVGs carries high risk of distal embolization. METHODS AND RESULTS: This study reports our initial experience with the PercuSurge GuardWire, a new device developed to prevent embolization during treatment of degenerated SVG. This device consists of a 190-cm-long, hollow 0.014-in guidewire with a central lumen connected to a distal occlusion balloon. A dedicated inflation device (the MicroSeal Adapter) was used to inflate the distal balloon and maintain complete lumen occlusion during balloon dilatation and stent implantation. A monorail aspiration catheter, connected to a vacuum syringe, was used to evacuate atherosclerotic and thrombotic debris. Angioplasty with stent implantation was performed in 15 degenerated SVGs (18 lesions). Procedural success was achieved in all patients with normal postprocedure flow (Thrombolysis in Myocardial Infarction grade 3). No distal embolization was observed. There were no major in-hospital adverse clinical events, including Q-wave or non-Q-wave myocardial infarction, emergency CABG, or death. All patients were asymptomatic at discharge. CONCLUSIONS: This preliminary series supports the feasible use of the PercuSurge GuardWire for retrieval of plaque debris and prevention of embolization in degenerated SVGs. The good tolerance of temporary occlusions without angiographic or clinical evidence of distal embolization represents encouraging early findings.  (+info)

Retrieval and analysis of particulate debris after saphenous vein graft intervention. (8/776)

OBJECTIVES: This study was designed to evaluate the composition and quantity of particulate debris resulting from vein graft intervention. BACKGROUND: Distal embolization and "no reflow" are frequent and important complications resulting from angioplasty of diseased saphenous vein grafts. Little is known about the composition and quantity of embolic particulate debris associated with vein graft intervention, and no intervention has been shown to protect against its clinical consequences. METHODS: A catheter system, designed to contain, retrieve and protect against distal embolization of this material, was evaluated during 27 percutaneous interventional saphenous vein graft procedures. Clinical, angiographic and pathologic analyses were performed. RESULTS: The duration of distal graft occlusion required to allow intervention and subsequent debris removal was 150 +/- 54 s, decreasing as experience was gained. Thrombolysis in Myocardial Infarction trial (TIMI) flow grade increased from 2.6 +/- 0.8 to 3.0 +/- 0.0. Creatine kinase (CK) rose above normal in three patients (11.1%) exceeding 3x normal in one (3.7%) resulting in the diagnosis of non-Q-myocardial infarction. Particulate material was identified following 21 of 23 procedures suitable for analysis. Particle size was 204 +/- 57 microm in the major axis and 83 +/- 22 microm in the minor axis. Particles consisted predominantly of soft acellular atheromatous material, such as that typically found under a fibrous cap. Semiquantitative analysis suggested that the quantity of particulate material was less following stenting than following balloon dilation. CONCLUSIONS: Particulate matter is commonly present following routine angioplasty and stenting of saphenous vein grafts. Containment, retrieval and analysis of this particulate debris are all feasible. Comparison to prior clinical experience is limited by small sample size. However, to the extent that these particles may contribute to distal embolization, no-reflow and infarction, such a system may contribute to the reduction of complications following vein graft intervention.  (+info)