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101.
Summary The relationship between the blood flow pattern immediately following coronary artery occlusion and the resulting infarct 24 hours later was studied in dogs treated with isoproterenol (0.5 g/kg/min for 2 hours) or with propranolol (2mg/kg every 6 hours). The coronary artery of a closed chest dog was perfused via a special cannula with arterial blood. A 2-mm diameter plastic bead was introduced into the perfusate to embolize a coronary branch. One minute after occlusion, radiolabelled microspheres were injected into the perfusate. The dogs were then allowed to recover. 24 hours later the dogs were reanesthetized and their hearts removed. The hearts were sliced into 4 mm thick sections and the microsphere distribution was visualized by autoradiography of the tissue. Superimposition of developed autoradiographs and tracings of the infarct pattern of stained sections allowed direct comparison of the blood flow pattern immediately after occlusion to the eventual pattern of infarction. In all 8 control dogs, all 6 isoproterenol dogs and all 12 propranolol dogs the lateral borders of blood flow and infarction were superimposable indicating no lateral change in infarct size resulting from treatment. In the control group there was a subepicardial region of the ischemic zone which did not infarct (15.2±2.3% of the ischemic zone). Though isoproterenol did not significantly change the size of this zone, propranolol increased it to 35.9±6,5% (p<0.005) indicating vertical but not lateral salvage.Supported by Grant HL-20648 from NIH: HLBI and a Grant-in-aid from the American Heart Association and with funds contributed in part by the Northwest Ohio Chapter, Inc.  相似文献   
102.
Objectives. This report evaluates the use of Gianturco coils to close large patent ductus arteriosus (PDAs) (≥3.5 mm) and describes transvenous delivery of 0.052-in. (0.132-cm) Gianturco coils.

Background. Coil closure of PDAs has become increasingly popular. However, the technique has significant limitations when used to close large PDAs. This report evaluates patient characteristics, PDA anatomy, hemodynamic variables, delivery technique and coil geometry to determine predictors of success.

Methods. Between January 1995 and January 1997, 16 of 118 patients undergoing catheterization for PDA closure were found to have large PDAs. Their median age and weight were 14 months (range 3 months to 43 years) and 8.5 kg (range 3.5 to 73), respectively. The mean PDA diameter was 4.3 mm (range 3.5 to 5.9). Closure of PDAs was attempted using transcatheter delivery of 0.038-in. (0.096-cm) and 0.052-in. coils. Differences in clinical, anatomic, hemodynamic and technical variables between successes and failures were compared.

Results. Eleven (69%) of 16 patients had successful closure of their PDA. Failures occurred only in patients <8 months of age with an indexed PDA diameter >7 mm/m and a pulmonary/systemic flow ratio ≥2.8:1. Use of 0.052-in. coils tended to reduce the incidence of embolization and the number of coils needed for closure.

Conclusions. Patients >8 months of age can have successful closure of large PDAs with currently available Gianturco coils. The 0.052-in. Gianturco coils can be used safely to close large PDAs in infants as small as 6 kg. Increased experience and improved coil design may improve closure rates of large PDAs in infants.  相似文献   

103.
应用Amplatzer房缺封堵伞堵塞成人特殊动脉导管未闭   总被引:9,自引:1,他引:9  
目的:评价Amplatzer房缺封堵伞(AASO)堵塞特殊类型动脉导管未闭(PDA)的可行性及近期效果。方法:采用经导管Amplatzer AASO堵闭特殊类型巨大PDA并重度肺动脉高压5例。术后24 h、60 d、180 d进行经胸超声心动图及X线胸片、心电图复查随访。结果:5例均堵闭成功;2例术后完全无分流,2例术后残余2mm左向右分流,1例残余明显穿伞分流,分别在60 d、180d随访中分流完全消失;血流动力学和心脏解剖在术后及随访期间有显著改善。结论:Amplatzer AASO可用于堵闭形态特殊、管径较大的PDA,即时残余穿伞分流率高,近期效果好。  相似文献   
104.
Patent ductus venosus   总被引:1,自引:0,他引:1  
BACKGROUND: Patent ductus venosus is extremely rare with only 14 cases reported in the world literature. We present a case of patent ductus venosus. METHODS AND RESULTS: A 29-year-old male was admitted with melaena stool caused by gastric haemorrhagic ulcers. Laboratory data disclosed severe anaemia; however, liver function tests were normal. Serum ammonia was also within the normal range. Serological viral markers for hepatitis B or C were all negative. The abdominal ultrasonography and computed tomography indicated a 12 mm diameter shunt located in the left lobe of the liver, which connected the portal vein with the left hepatic vein. After treatment for gastric ulcers, percutaneous transhepatic portography was performed and an enormous shunt connecting the umbilical portion of the portal vein with the left hepatic vein was revealed. CONCLUSIONS: Histological findings of the liver biopsy showed that portal venules could not be observed in the portal areas and that no fibrosis or inflammatory cell infiltration were shown. Because of the anatomical position of the shunt, the case was diagnosed as patent ductus venosus.  相似文献   
105.
沉默型动脉导管未闭的血流动力学特征及治疗探讨   总被引:2,自引:0,他引:2  
目的 探讨沉默型动脉导管未闭 (patentductusarteriosus ,PDA)的血流动力学特征及治疗。方法 对临床结合超声心动图诊断的 7例沉默型PDA病人进行心导管检查 ,术后 3个月、6个月及每年随访一次。结果  7例病人肺动脉平均压平均为 (16 0± 2 4 )mmHg ,肺循环和体循环血流量比 (Qp/Qs)为 1 0 8± 0 0 2 ,左向右分流量平均为 (0 32± 0 0 8)L/min ,左向右分流量占肺循环血流量比例平均为 0 0 98± 0 0 2 4。PDA最窄处平均直径为 (0 9± 0 2 )mm。 7例病人均未行外科手术和介入治疗。平均随访 9 5个月 (临床、心电图、超声心动图 ) ,未发现房室腔增大、肺动脉压增高 ,无感染性动脉内膜炎和心内膜炎发生。结论 沉默型PDA的左向右分流量很少 ,对病人的血流动力学影响小。沉默型PDA病人是否需要治疗尚无定论。  相似文献   
106.
Objectives: To evaluate all complications that occurred during or after cardiac catheterizations for Amplatzer PFO device closure of patent foramen ovale (PFO), determine the cause of the complications and recommend techniques to minimize complications in the future. Background: Rare complications were reported to the manufacturer of the Amplatzer PFO occluder since the introduction of the device. Methods: A panel of independent physicians reviewed all complications reported to the manufacturer to determine whether the complication was related to the device or related to the cardiac catheterization procedure. Demographic data, echocardiograms, operative reports, and time to occurrence of complications were reviewed. Results: A total of 11 events were reported. Only two patients had device related complications (erosion), an incidence of 0.018%. Two patients were found to have additional atrial septal defect after PFO closure. Two patients were thought to have an inflammatory reaction without any serious sequelae. Five complications were related to the cardiac catheterization procedure (atrial appendage perforation). Conclusions: Device related complications after Amplatzer PFO occluder placement are extremely rare. Cardiac catheterization related complications appear to be the most common cause of the hemodynamic compromise. Careful manipulation of catheters and wires, recognition of the location of the catheter by fluoroscopy and echocardiography will decrease the risk of such complications. © 2008 Wiley‐Liss, Inc.  相似文献   
107.
We are presenting a case of floating left and right atrial formations on an atrial septal defect occluder system (23mm StarFLEX)-Occluder) initially supposed to be thrombotic appositions in a 57-year-old man. The closure was performed on the background of left hemispheric stroke and atrial septal aneurysm (ASA) with patent foramen ovale (PFO). The suspect structures were detected in the 6-month follow-up by transesophageal echocardiography (TEE). The patient underwent a successful surgical explantation of the closure device and closure of the patent foramen ovale (PFO) using a pericardial patch. The pathological evaluation of the biatrial device associated appositions revealed hytrophic heart muscle tissue with perifocal scarring and purulent abscess-forming, granulating and foam-cell including inflammatory foreign body reaction instead of the expected thrombus formation.  相似文献   
108.
Patent foramen ovale (PFO) is thought to be associated with cryptogenic stroke and migraine headache. Saline contrast echocardiography (SCE) is the gold standard for identifying the presence of right-to-left shunt, whether from PFO or pulmonary arteriovenous malformation (PAVM). The timing of left heart contrast entry during SCE is used to distinguish a PFO from a PAVM, a method that is not as specific as previously thought. In this report, we describe a patient with a SCE demonstrating the early appearance of left heart bubbles during good effort Valsalva injections that is ultimately proven to be due to a PAVM. The case illustrates the limited specificity of left heart contrast timing during SCE as the sole criteria for differentiating intracardiac and extracardiac shunts.  相似文献   
109.
This case report describes a patient undergoing patent foramen ovale (PFO) closure for recurrent transient ischemic attacks. A CardioSEAL device was placed, but immediately prolapsed into the left atrium in an unstable position. We describe a novel percutaneous technique that allowed capture of the CardioSEAL device and closure of the PFO.  相似文献   
110.
We report a remarkable case of right atrial rupture, 3 years after transcatheter closure of a secundum atrial septal defect, and 7 months after permanent transvenous two‐chamber pacemaker implantation. The etiology of the rupture remains unclear, but the presence of the two intracardiac devices is probably not coincidental. © 2008 Wiley‐Liss, Inc.  相似文献   
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