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This describes our preliminary experience with percutaneous brachial approach for cardiac catheterization, by using 5 French (F) preformed catheters. Thirty patients (pts) were studied from the left arm (Group A) with a 5F sheath and 5F Judkins catheters and 30 from the right arm (Group B) with 5F sheath and 5F Amplatz catheters. Pigtail catheters (5F) were used for the left ventricular angiograms in all patients. In 10 patients arterial velocity signals and radial and ulnar artery blood pressures were monitored with the Doppler ultrasonic velocity detector before and immediately after each procedure, and 24 hours later. Arterial puncture was carried out successfully in each patient by using a 18-gauge Potts-Cournand needle. The puncture site was as close as possible to the ante cubital fossa where the artery is less mobile. Both coronary arteries were selectively opacified and the left ventricular angiography was done on every patient. The diagnostic quality of the angiograms was evaluated by the visual analogue scale and the results were not different from those obtained with the femoral approach in our catheterization laboratory. In 3 out of 30 pts in group B it was impossible to obtain a good left coronary opacification with Amplatz catheters for anatomical reasons, thus the right femoral approach was preferred. Brachial artery occlusion occurred in 1 patient from group B and needed surgical thrombectomy carried out to restore normal radial and ulnar pulses.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
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BACKGROUND. Studies in animals have shown that serotonin constricts coronary arteries if the endothelium is damaged, but in vitro studies have revealed a vasodilating effect on isolated coronary segments with an intact endothelium. To investigate the effect of serotonin in humans, we studied coronary-artery cross-sectional area and blood flow before and after the infusion of serotonin in seven patients with angiographically normal coronary arteries and in seven with coronary artery disease. METHODS. We measured the cross-sectional area of the coronary artery by quantitative angiography and coronary blood flow with an intracoronary Doppler catheter. Measurements were obtained at base line and during intracoronary infusions of serotonin (0.1, 1, and 10 micrograms per kilogram of body weight per minute, for two minutes). We repeated the measurements after an infusion of ketanserin, an antagonist of serotonin receptors that is thought to block the effect of serotonin on receptors in the arterial wall but not in the endothelium. RESULTS. In patients with normal coronary arteries, the highest dose of serotonin increased cross-sectional area by 52 percent (P less than 0.001) and blood flow by 58 percent (P less than 0.01). The effect was significantly potentiated by administration of ketanserin. In patients with coronary-artery atherosclerosis, serotonin reduced cross-sectional area by 64 percent (P less than 0.001) and blood flow by 59 percent (P less than 0.001). Ketanserin prevented this effect. CONCLUSIONS. Serotonin has a vasodilating effect on normal human coronary arteries; when the endothelium is damaged, as in coronary artery disease, serotonin has a direct, unopposed vasoconstricting effect. When considered with other evidence, these data suggest that platelet-derived factors such as serotonin may have a role in certain acute coronary ischemic syndromes.  相似文献   
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The pressure gradient across coronary stenoses is measured routinely during angioplasty. Due to the finite size of the angioplasty catheter within the stenotic cross section, the remaining luminal area is further reduced and the transstenotic gradient may be overestimating the "true" pressure drop. This "true" pressure gradient can be approximated from the mean coronary blood flow and the stenosis geometry from theoretical models. Goal of this study was to assess the values and limitations of the in vivo measurements of the pressure gradient versus the calculated values. Therefore, flow in the great cardiac vein was measured in 13 patients before and/or after angioplasty of a proximal left anterior descending stenosis, not filled by collaterals. The Poiseuille and turbulent contributions to flow resistance were determined from stenosis geometry assessed by quantitative coronary angiography. A fourfold increase in the luminal area (from 0.7 mm2 pre- to 2.8 mm2 post angioplasty) was associated with a fourfold decrease in the in vivo measured transstenotic gradient (from 59 mm Hg pre- to 13 mm Hg post angioplasty). The occlusion area and the measured gradient were linearly correlated: gradient = 69-17 X occlusion area (r = 0.76). However, as expected, the transstenotic gradient systematically overestimated the theoretical gradient calculated from the laws of fluid dynamics. A nonlinear relation was found between the calculated gradient P and the occlusion area As: P = 15 X As-2 (r = 0.87).  相似文献   
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IntroductionReoperative parathyroidectomy for persistent and recurrent primary hyperparathyroidism is dependent on radiology. This study aimed to compare outcomes in reoperative parathyroidectomy at a single centre using a combination of traditional and newer imaging studies.Materials and methodsRetrospective case note review of all reoperative parathyroidectomies for persistent and recurrent primary hyperparathyroidism over five years (June 2014 to June 2019; group A). Imaging modalities used and their positive predictive value, complications and cure rates were compared with a published dataset spanning the preceding nine years (group B).ResultsFrom over 2000 parathyroidectomies, 147 were reoperations (101 in group A and 46 in group B). Age and sex ratios were similar (56 vs 62 years; 77% vs 72% female). Ultrasound use remains high and shows better positive predictive value (76% vs 57 %). 99mTc-sestamibi use has declined (79% vs 91%) but the positive predictive value has improved (74% vs 53%). 4DCT use has almost doubled (61% vs 37%) with better positive predictive value (88% vs 75%). 18F-fluorocholine positron emission tomography-computed tomography and ultrasound-guided fine-needle aspiration for parathyroid hormone are novel modalities only available for group A. Both carried a positive predictive value of 100%. Venous sampling with or without angiography use has decreased (35% vs 39%) but maintains a high positive predictive value (86% vs 91%). Cure rates were similar (96% vs 100%). Group A had 5% permanent hypoparathyroidism, 1% permanent vocal cord palsy and 1% haematoma requiring reoperation. No complications for group B.ConclusionOptimal imaging is key to good cure rates in reoperative parathyroidectomy. High-quality, non-interventional imaging techniques have produced a shift in the preoperative algorithm without compromising outcomes.  相似文献   
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A 26‐year‐old man with a history of heavy marijuana and minimal tobacco use was found to have extensive bilateral lung bullae and interstitial fibrosis, heavily infiltrated by pigmented macrophages. These features can be associated with marijuana smoking. The differential diagnoses in this patient are also discussed.  相似文献   
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