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101.
Background: Coronary angioplasty, although of proven use in partial occlusion, has not been shown to be of similar benefit in chronic total occlusion. Aims: To assess the utility of coronary angioplasty in chronically totally occluded vessels in patients undergoing angioplasty and to determine the success of TIMI-I flow before angioplasty compared to those patients with TIMI-O flow. Methods: A group of 178 consecutive patients (from 1984 to 1992), who underwent angioplasty of a chronic occlusion, were analysed. There were 136 males and 42 females with a mean age of 56.9 years. Results: Initial technical success was achieved in 65%. Patients with TIMI-I flow before angioplasty had a higher chance of success (700%) compared to those with TIMI-O flow (53%), p < 0.04. During hospitalisation six patients suffered myocardial infarction (MI), two required surgery and one patient died. During a mean follow-up of 2.8 years the overall survival rate was 95% for the group as a whole. Freedom from coronary surgery was significantly greater in patients with successful angioplasty (93%) than those without (66%, p < 0.002). The above two populations also showed a significant difference in the incidence of angina (35%vs 56%, p < 0.0003). However, the incidence of MI (6%vs 5%, p > O.5) and cardiac survival (98%vs 94%, p > 0.l) did not differ significantly in the two groups. Restenosis occurred in 63% of the 95 patients (82%) who returned for follow-up angiography. Eighteen of the 59 patients (28%) with restenosis had a reocclusion. Conclusion: The success rate for angioplasty of chronic total occlusions is acceptable. Long-term clinical benefit in patients with successful angioplasty is suggested by the high freedom from angina and the lesser need for coronary surgery. No major impact on either the incidence of MI or cardiac survival was noted when patients who had coronary surgery were included, although it must be emphasised that the sample size in this study was insufficient to detect a difference in these outcome variables.  相似文献   
102.
Background We have reported that percutaneous radiofrequency ablation (RFA) with balloon occlusion of the hepatic artery (balloon-occluded RFA), using an expandable electrode, increases the coagulation area. In this study, we investigated the efficacy of balloon-occluded RFA and balloon-microcatheter-occluded RFA, using a cool RF single electrode.Methods We studies 41 patients with 47 hepatocellular carcinoma (HCC) lesions. We treated 28 patients (32 nodules) with balloon-occluded RFA, 5 patients (6 nodules) with balloon-microcatheter-occluded RFA, and 8 patients (9 nodules) with standard RFA. Initial therapeutic efficacy was evaluated with dynamic computed tomography performed 1 week after one session of treatment.Results One session of treatment was done for 20 nodules (62.5%) in the balloon-occluded RFA group and for 4 nodules (66.7%) in the balloon-microcatheter-occluded RFA group. We compared the coagulation diameter for balloon-occluded RFA (7 nodules), balloon-microcatheter-occluded RFA (6 nodules), and standard RFA (9 nodules) after one application cycle (12min). The greatest dimension of the area coagulated by balloon-occluded RFA was significantly larger (greatest long-axis dimension, 47.6 ± 7.8mm; greatest short-axis dimension, 33.4 ± 7.5mm) than that coagulated by standard RFA (greatest long-axis dimension, 35.3 ± 4.7mm; greatest short-axis dimension, 25.9 ± 3.7mm; P = 0.002 for greatest long-axis dimension; P = 0.041 for greatest short-axis dimension). However, there was significant difference only in the greatest short-axis dimension of the area coagulated comparing balloon-microcatheter-occluded RFA and standard RFA.Conclusions We consider balloon-occluded RFA using a cool RF electrode to be superior to standard RFA for the treatment of HCC, especially when larger coagulation volumes are required.  相似文献   
103.
Prolonged dilatation with an autoperfusion balloon catheter (APBC) (High-Flow-CPC-Mainz (Schneider) in 23 cases and Stack Perfusion (ACS) in 50 cases) was carried out in 73 patients (60 men, 13 women, mean age 59.3 +/- 8.8 years) with acute vascular complications occurring during PTCA (25 occlusive dissections (34%), five thrombotic occlusions (7%), 42 non-occlusive dissections (58%) and one non-occlusive thrombus with reduction of flow (1%)) in order to avoid stent implantation or emergency bypass surgery. On average 1.5 +/- 0.8 inflations were carried out per patient with a mean maximum inflation time of 14.1 +/- 8.4 min and a mean total inflation time of 16.8 +/- 12.3 min. In 61 patients (83.5%), the vascular complication could be controlled successfully with APBC, but in 12 APBC was not successful. Eight patients (11%) had emergency surgery. A stent was implanted in three patients (4.1%), and one suffered an acute myocardial infarction. Out of the 61 patients with positive result after prolonged dilatation, the hospital phase was uncomplicated in 53 (86.9%), five (8.2%) suffered an infarct with a maximum rise in CK of 350 U.l-1, two with multivessel disease had elective operations and one was dilated a second time because of a subacute reocclusion. Our experience indicates that when an acute vascular complication occurs, prolonged dilatation with an APBC is good interventional therapy avoiding stent implantation or emergency bypass surgery. However, new techniques cannot always replace surgery so an emergency bypass operation may still be necessary.  相似文献   
104.
Catheter balloon valvuloplasty of stenotic aortic valves has met with generally poor short- and long-term clinical results. Part of this problem resides with the lack of recognition of various etiologies of aortic stenosis. Part I of this review discusses the various etiologies of aortic stenosis and provides an anatomic basis for successful valve dilation. Results of an in vitro study indicate stenotic aortic valves are dilated by various mechanisms (cracking, stretching) based in part upon the etiology of the aortic valve stenosis.  相似文献   
105.
对 2 6例二尖瓣狭窄 (MS)合并心房颤动 (Af)患者 ,在行经皮球囊二尖瓣扩张术 (PBMV)前给大剂量肝素短程抗凝 ,并对其中 1 9例在术后即给予同步直流电复律。结果 二尖瓣口面积 (MVA)由 0 92± 0 2cm2 扩大至 1 95± 0 3 7cm2 ,左房平均压 (LAP)由 3 1 2± 1 2 7kPa降至 1 4 2± 0 85kPa,而左房内径 (LAD)由 52 7± 8 1mm缩小至 4 2 5± 5 9mm。 2 6例均无血栓栓塞并发症及出血并发症 ;1 9例术后即刻行同步电复律者 1 5例 ( 78 9% )复律成功。  相似文献   
106.
目的 通过与心导管测量对比来评价经皮肺动脉瓣球囊成形术(PBPV)前后应用Doppler超声心动图估测跨瓣压差的临床价值。方法 对178例患者在行PBPV术前利用Doppler测量肺动脉瓣跨瓣压差(△P’),与相应的心导管测量值(△P)作相关性分析;并利用Doppler对PBPV术后48例患者进行了4~102个月(平均19.5个月)的随访。结果Doppler测量的△P’值与导管测量的△P值之间有着良好的直线相关性,r值为0.80,P<0.05;随访中Doppler测量的△P’值与PBPV术后即刻导管测量的△P值之间差异无显著性(P=0.05)。结论Doppler超声作为一种准确、无创、简便而有效的检查方法,对估计PBPV术前肺动脉瓣狭窄程度,评价术后疗效有较高的临床应用价值。  相似文献   
107.
To facilitate pancreatic stone retrieval, four patients with chronic pancreatitis and pancreatic stones underwent endoscopic pancreatic sphincter balloon dilation (EPSBD) rather than pancreatic sphincterotomy. Extracorporeal shock wave lithotripsy combined with endoscopic removal was carried out in three patients. Stone removal following EPSBD was completely successful in all four patients. Patients showed no severe complications during the dilation procedure. In one patient, to prevent pancreatitis, an endoscopic nasopancreatic drain was placed for 1 week after EPSBD. Compared with pancreatic sphincterotomy, EPSBD can be performed safely in patients with chronic pancreatitis to assist in the extraction of pancreatic duct stones. Use of the EPSBD procedure in cases of chronic pancreatitis provides a useful approach to improve endoscopic clearance of pancreatic duct stones.  相似文献   
108.
BACKGROUND: Transcatheter closure of atrial septal defect (ASD) is an alternative approach to surgery in selected patients. Balloon stretched diameter (BSD) is considered as the standard way of measuring ASD size. Three-dimensional transesophageal echocardiography (3D-TEE) provides views of the ASD allowing its measurement and identifying its spatial relation with neighboring structures. Our aim was to compare the BSD and 3D-TEE methods to measure the ASD size before transcatheter closure. METHODS AND RESULTS: Seventy-six consecutive patients were enrolled for ASD device closure. Three-dimensional transesophageal echocardiography and balloon sizing were adequately performed in 70 patients before the defect closure. The mean maximal diameter measured by 3D-TEE was 20 +/- 15 mm (range 10-28) while the mean BSD was 22 +/- 4.8 mm (range 9-31). When comparing the 3D-TEE and transcatheter measurements, there was a good correlation between the two methods (y = 3.15 + 0.77x; r = 0.8). The defect as viewed by 3D-TEE was unique in 54 patients and multiple in 16 patients. In patients with a single defect, the correlation between the two methods was high (y = 1.74 + 0.84x; r = 0.85) while patients with multiple ASDs, the correlation was poor (y = 12.4 + 0.4x; r = 0.45). Transcatheter closure was performed successfully in 86%. The mean size of the Amplatzer device was 23 +/- 4.8 mm (range 4-32). The reference to choose the size of the device was the BSD in single defects and the 3D-TEE maximal diameter in multiple defects. CONCLUSION: Three-dimensional transesophageal echocardiography and transcatheter methods are two complementary techniques for the success of transcatheter ASDs closure.  相似文献   
109.
The purpose of this study was to examine the influence of the atrial communication created during transseptal passage of the Inoue balloon catheter on calculated mitral valve area after balloon valvotomy for severe mitral stenosis. Even in the absence of oxymetric evidence for a shunt, atrial septal puncture may result in left-to-right shunting of blood with reported spurious increases in postvalvotomy mitral valve area calculations ranging from 16–29% in prior studies. Occlusion of the septal puncture site after double balloon valvotomy has previously been shown to result in decreased postvalvotomy mitral valve area determinations. We evaluated 20 patients undergoing mitral dilation. Each patient had three postvalvotomy measurements made: (1) with the Inoue balloon catheter positioned across the septum, (2) during septal occlusion with a 7F balloon-tip catheter, and (3) without any catheters across the septum. With the Inoue catheter across the septum after successful valvotomy, the cardiac output was 4.6 ± 1.5 L/min and the calculated mitral valve area was 1.7 ± 0.5 cm2. No difference was found in either cardiac output or valve area when the septum was unobstructed by catheters. During septal occlusion, however, the postvalvotomy cardiac output decreased to 4.3 ± 1.3 L/min (P<0.001) and the calculated mitral area decreased by 12% to 1.5 ± 0.5 cm2 (P<0.001). The calculated mitral valve areas determined with the Inoue catheter in place after valvotomy were in agreement with echo derived data. Although statistically significant differences in post-Inoue valvotomy cardiac output and calculated mitral valve area were found during septal occlusion, these differences were small. Furthermore, echocardiographic valve area measurments agreed with invasively determined mitral valve areas regardless of whether or not the septum was ccluded. We conclude that septal occlusion is not necessary for valve area measurement after Inoue balloon mitral valvotomy. © Wiley-Liss, Inc.  相似文献   
110.
目的评价主动脉球囊反搏术(IABP)在急性心肌梗死(AMI)合并心源性休克治疗中的应用价值。方法选取AMI合并心源性休克患者65例,其中IABP组30例,在IABP支持下行急诊经皮冠状动脉介入治疗(PCI),对照组35例,单纯行急诊PCI治疗。结果IABP组患者在IABP支持下,30 min后血流动力学指标改善,2~8 h血流动力学稳定,均完成梗死相关血管再通,没有血管再闭塞事件发生,无术中死亡,院内死亡率40%;对照组患者院内死亡率74.3%,其中6例在术中死亡。结论IABP可明显改善AMI合并心源性休克患者的血流动力学指标,增加冠状动脉的灌注;IABP可提高急诊PCI的成功率,减少术后低心排综合征及血管再闭塞事件的发生,降低院内死亡率,明显改善了AMI合并心源性休克患者的预后。  相似文献   
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