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71.
We report on the procedural outcome in 30 patients with acute coronary syndromes in whom stent implantation was attempted without predilatation. Elective stent implantation in infarct related coronary arteries after myocardial infarction might be superior to agioptasty alone. We retrospectively analyzed the result from 88 patients who had stent implantation for myocardial infarction or unstable angina. In 30 of these patients we attempted to implant a stem without predilating the vessel. Successful stent deployment was possible in 26 (87%). In four patients where it was not possible to cross the lesion, we could withdraw the stent to predilate the lesion. We did not attempt direct stent implantation if the lesion was calcified, long, involved major side branches or a tortuous proximal segment, or where the length of the lesion and diameter of the distal vessel could not be measured. A low profile, premounted stent was used. Procedural success was 100% in the group of 30 patients with direct stent implantation— not significantly different from the 93% success in the group of 58 patients whose lesions were predilated first but had more complex lesions. The incidence of complications did not differ significantly between the two groups and no instances of stent loss or displacement occurred in the direct implantation group. Stent implantation without predilatation is feasible and not associated with a higher incidence of complications, provided lesions that allow easy positioning of the stent are selected. It can shorten the procedure and duration of ischemic occlusion of the vessel, which would be of particular advantage in unstable patients or where a large area of myocardium is jeopardized.  相似文献   
72.
The Multi-Track System is a simplified double-balloon technique for percutaneous mitral valvuloplasty. Here we describe the technique and report the results obtained using it. The Multi-Track catheter has a short distal tip for connection to the guidewire. This leaves the rest of guidewire free to receive other catheters. Various catheters can be introduced over the same guidewire. The balloons are introduced one after the other allowing a smaller size of vascular access and transseptal passage. Furthermore, simultaneous pressure measurements in the left atrium and left ventricle are possible through a simple venous access, allowing avoidance of arterial puncture. We used this technique worldwide between June 1994 and February 2000 for the treatment of 153 patients with mitral stenosis worldwide. In 12 cases, the procedure was done using the exclusive venous approach. The mean mitral valve area increased from 0.75 ± 0.22 to 2 ± 0.33 cm2and the mean left atrial pressure dropped from 27 ± 8 to 11 ± 4 mmHg. Four patients had a significant increase in mitral regurgitation, requiring surgical treatment in two patients. There was no mortality. The Multi-Track system is a valid user-friendly and cost-effective alternative for the treatment of mitral stenosis. It is a rapid and effective procedure associated with low risks.  相似文献   
73.
74.
ASSESSMENT OF ZINC NUTRITIONAL STATUS OF PELLAGRA PATIENTS   总被引:1,自引:0,他引:1  
The objective of the present study was to assess zinc nutritionalstatus in alcoholic patients with pellagra using plasma, hair,urine and nail zinc levels, as well as the zinc tolerance test.The study was conducted on 81 patients, 73 males and eight females.Zinc parameters were compared with those of 84 individuals withno apparent disease aged 23–45 years. Plasma zinc levelswere lower in patients with pellagra than in the controls (P< 0.01). The results of the zinc tolerance test showed that:(1) basal zinc levels were 69.7 ± 16.8 µg/100 mlin pellagrins and 82.3 ± 34.0 µg/100 ml in thecontrols (P < 0.01); (2) after 1 h the increase in plasmalevels was similar in the pellagrin and control groups; (3)during the second hour the increase was more marked in the controls(P < 0.01), and the same was observed during the third andfourth hours (P < 0.05). Urinary zinc excretion (mg/24 h)was higher in pellagrins (P < 0.01). Zinc concentration inhair and toenails did not differ between pellagrins and controls.We conclude that pellagrins present zinc deficiency as demonstratedby plasma and urine zinc levels and by their abnormal responseto the zinc tolerance test. We suggest that hair and nail zinclevels should not be used to assess zinc nutritional statusin patients with pellagra.  相似文献   
75.
This report describes a patient with polycystic disease of the kidneys and the liver and an aneurysm of the proximal right coronary artery. Transthoracic and transesophageal echocardiographic imaging showed a 5 times 5 cm oval-shaped, spherical tumor in the atrioventricular corner. The tumor was partially filled with homogenous echostructures. Coronary angiography showed aneurysmatic configuration of the right coronary artery, but no region demonstrating a mass of similar size and shape as seen by echocardiography. The finding of a partially thrombosed coronary artery aneurysm was subsequently confirmed by surgery.  相似文献   
76.
This review examines recent evidence from structural and functional studies that interstitial cells of Cajal (ICC) play a major role in control of gastrointestinal function. These cells, identified to date only by their structural and somewhat selective staining characteristics, form networks in the region of the myentehc plexus and in or adjacent to circular muscle. Those in circular muscle are often coupled to one another and to smooth muscle cells by gap junctions and are closely innervated by a high proportion of enteric nerves, especially those containing vasoactive intestinal polypeptide (VIP). ICC in the myenteric plexus often have no visible connections by gap junctions to smooth muscle. There is a growing body of evidence from study of small intestine and colon that these cells are either the pacemakers or provide clocks for the pacemaking function of the gut (vahously known as slow waves, pacesetter potentials or control potentials). Additional evidence suggests that they may play a role in neurotransmission of non-adrenergic, non-cholinergic inhibitory activity. This review summarizes our current understanding and attempts to point the way for future research.  相似文献   
77.
78.
A 30-year-old woman with Ebstein's anomaly presented with a sustained, wide QRS complex tachycardia exhibiting a left bundle branch block morphology. Serial electrophysiological studies revealed right and left bundle branch reentry tachycardias refractory to many conventional antiarrhyfhmic drugs, Radiofrequency and direct current catheter ablation of the right bundle branch failed to control the tachycardias. The patient subsequently underwent extensive endocardial cryoablation to the right bundle branch resulting in cure of her arrhythmia.  相似文献   
79.
VDD stimulation using a single catheter for atrial sensing and ventricular sensing and pacing has become a reality. In order to compare the quality of the cavitary atrial electrogram (AEG) and to determine the intraatrial P wave direction and conduction time (CT), we compared, in an acute study, three different types of atrial electrode systems using four different leads, in 53 patients in sinus rhythm. The three electrode systems were: (1) one experimental system with quadripolar orthogonal electrodes using the Goldreyer concept; (2) one experimental system with quadripolar whole ring electrodes; (3) two systems with diagonally oriented half-ring electrodes, one experimental quadripolar and one bipolar CCS commercial (Polysafe A-Track lead). For the experimental systems, the four electrodes forming two independent bipolar pairs were situated on the intraatrial floating portion of a single lead and one supplemental electrode was distally positioned in the right ventricular apex. Bipolar AEGs were recorded at the high and at the low levels of the right atrium. For the CCS lead, the single bipolar AEG was recorded at the high level of the right atrium only. The highest AEG amplitude and the highest values for ventricular far-field rejection were provided by both diagonally oriented half-ring electrodes at the high atrial level and by the whole ring electrodes at the low atrial level. For both atrial levels, the orthogonal electrode system provided the smallest AEG amplitudes, the highest ventricular electrogram amplitudes, and therefore, the smallest values for ventricular far-field rejection.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
80.
Allogeneic transplantation from an HLA-matched family member has been shown to be effective in reconstituting normal haemopoiesis in young people with severe cytopenias, classified as myelodysplastic syndrome (MDS) or severe aplastic anaemia (SAA). Unrelated donor transplant is a therapeutic choice for patients without a suitable family member donor. We report the outcome of seven patients < 20 years old with SAA and 10 with MDS treated with BMT from an HLA A,B DRB1 matched ( n  =8) or A or B locus mismatched ( n  =9) unrelated donor at the University of Minnesota between March 1988 and August 1995. Primary graft failure occurred in two patients and secondary graft failure in one, who was subsequently successfully engrafted with a second donor marrow infusion. Grades II–IV GVHD occurred in 10/16 (63%), and grades III–IV in 6/16 (37%) evaluable patients. Nine of the 17 patients (six with MDS and three with SAA) survive with full donor chimaerism, a median of 1.2 years post-BMT (range 3 months to 7 years). We recommend early referral for consideration of unrelated donor BMT for young patients with MDS, and patients with SAA without response to immunosuppression.  相似文献   
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