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1.
Continuous monitoring of left ventricular (LV) function during percutaneous transluminal coronary angioplasty (PTCA) was performed in 40 patients (53 +/- 2 years) with a miniature, nuclear detector system after labeling the patients' red blood cells with technetium-99m. Balloon dilation (113 seconds, range 60 to 240) induced on average a 0.12 ejection fraction (EF) unit (19%) decrease in the LVEF, which was explained by a 34% increase in end-systolic counts. Balloon dilation of the left anterior descending artery (n = 23) produced a decrease in the LVEF of 0.17 +/- 0.13 EF units compared with the decrease of 0.06 +/- 0.07 EF units in patients undergoing dilation of the left circumflex artery (n = 9) and 0.05 +/- 0.04 EF units in patients treated for a stenosis of the right coronary artery (n = 8), (p = 0.02). Balloon deflation was associated with an immediate return to pre-PTCA levels. In 10 patients with 2 identical balloon occlusions, the second occlusion led to a significantly less decrease in the LVEF (0.41 +/- 0.14 vs 0.44 +/- 0.15) and electrocardiographic ST-segment deviation (88 +/- 54 microV vs 65 +/- 42 microV) than the first. We conclude that PTCA is associated with an abrupt transient decrease in the LVEF. The effect of balloon occlusion of the left anterior descending artery is more pronounced than balloon occlusion of the left circumflex and the right coronary arteries. Neither single nor multiple balloon occlusions were associated with post-PTCA global LV dysfunction, whereas the lesser degree of LV dysfunction and electrocardiographic signs of myocardial ischemia during the second of 2 identical balloon occlusions suggests that preconditioning can be induced during PTCA.  相似文献   

2.
With technological advances in equipment and increased experience of operators, the success rates of percutaneous transluminal coronary angioplasty (PTCA) now exceed 90%. However, acute periprocural occlusion continues to complicate approximately 6% of all procedures, and many of these occlusions are due to intracoronary (IC) thrombus. Patients at highest risk for this complication include those with acute ischemic syndromes or with angiographically apparent thrombus. These individuals may be candidates for the use of prolonged heparin infusions prior to dilatation, intracoronary thrombolytic therapy, or monoclonal antibody directed against the platelet glycoprotein IIb/IIIa receptor. All patients undergoing PTCA should receive adequate antiplatelet therapy, including aspirin, and heparin with dosing monitored by activated clotting times (ACT). In addition, some recommend the use of ionic contrast material. When IC thrombus accumulates following intervention, initial therapy should include IC nitroglycerin followed by a combination of redilatation and IC urokinase infusion. Prolonged balloon inflations may be useful, particularly with the use of autoperfusion catheters. Platelet glycoprotein IIb/IIIa receptor antagonists may prove to be beneficial in this situation as well. If the patient's clinical status deteriorates in spite of these measures, emergency coronary artery bypass graft surgery may be required.  相似文献   

3.
The usefulness of percutaneous transluminal coronary angioplasty (PTCA) was assessed in patients with exercise-induced asymptomatic myocardial ischemia (silent ischemia) and compared with exercise-induced symptomatic myocardial ischemia (symptomatic ischemia). Patients with single vessel coronary artery disease (51 with angina pectoris, 40 with old myocardial infarction) and evidence of stress-induced ischemia on thallium-201 single photon emission computed tomography (SPECT) underwent successful PTCA. Thirty-seven percent of angina patients and 60% of infarction patients showed asymptomatic exercise-induced ischemia. There was no significant difference in population characteristics between silent and symptomatic patients. Patients with silent angina had significantly higher percentage thallium uptake and washout rate than symptomatic patients. After PTCA, both percentage diameter stenosis and percentage thallium uptake were improved in all patients with angina irrespective of the presence or absence of symptoms. There were no significant differences in percentage thallium uptake and washout rate between patients with silent and symptomatic infarction. After PTCA, percentage diameter stenosis, percentage thallium uptake, and washout rate improved in all infarction patients irrespective of the symptoms. Zero percent of silent angina patients, 12% of symptomatic angina patients, 12% of silent infarction patients, 19% of symptomatic infarction patients had cardiac events during about 4.5 years after PTCA. The incidence of cardiac events did not significantly differ in any patient group. PTCA improved myocardial perfusion in all patients, and the incidence of cardiac events did not differ between the silent and symptomatic groups. Revascularization with PTCA is suitable for patients with silent as well as symptomatic ischemia.  相似文献   

4.
5.
BACKGROUND: Myocardial ischemia and myocardial infarction are the most serious complications of coronary artery lesions in children with Kawasaki disease (KD). Therefore, early detection and treatment of myocardial ischemia in patients with KD is essential. We studied the effectiveness of percutaneous transluminal coronary angioplasty (PTCA) in patients with silent myocardial ischemia detected by dobutamine stress 99mTc myocardial scintigraphy (TMS), body surface mapping (BMS), and signal-averaged ECG late potentials (ELP). METHODS AND RESULTS: Eight of 76 asymptomatic patients with a coronary stenosis >25% and a positive dobutamine stress test were considered to have silent myocardial ischemia. All eight patients had >95% stenoses demonstrated by coronary angiography (CAG) just before PTCA. After PTCA, CAG showed that all of the coronary artery stenoses had been reduced to <50%. Additionally, intravascular ultrasonography (IVUS) performed in five patients before and after PTCA demonstrated adequate dilation of the coronary stenosis after PTCA. All eight patients underwent dobutamine stress TMS, BMS, and ELP 2 to 3 months after PTCA, which demonstrated no regions of myocardial ischemia. Approximately 6 months later, CAG was performed in all eight patients, and only one patient had developed restenosis. CONCLUSIONS: PTCA effectively dilates stenotic coronary arteries in children with KD. Moreover, dobutamine stress TMS, BMS, and ELP are useful for detecting silent myocardial ischemia and estimating the effectiveness of PTCA. Furthermore, IVUS is useful for evaluating the severity of coronary artery lesions before and after PTCA in patients with KD.  相似文献   

6.
In female patient, 19 years old, disease occurred when she was 5. Thoracotomy with atypical resection of lung part was performed for the abscess in right lobe. Nocardia was bacteriologically confirmed. In the next 3 years, she was treated for pneumonia several times. When she was 19, abscess-forming pneumonia that recurrently occurred after the antibiotic therapy cease was established in right lobe. Nocardia was isolated by bronchoscopically taken aspirate, bacteriologically stained by Gramm, Ziehl-Neelsen and Kinyon and cultivated on several bacteriological and mycological media. She has been treated by antibiotic combination (sulfamethoxazole + trimethoprim and amoxicillin + clavulanic acid and minocycline) for 10 months. Subjective discomforts disappeared after the therapy, biohumoral findings were normal, and smaller pleuropulmonary adhesions on the right side could have been radiologically observed.  相似文献   

7.
Improvement in exercise capacity is an important clinical effect of percutaneous transluminal coronary angioplasty (PTCA), and was assessed in patients with and without previous myocardial infarction (MI) undergoing PTCA. We prospectively followed patients with exercise testing before and 2 weeks after angioplasty in 415 patients, 170 (41%) of whom had a previous MI. A third exercise test was performed 20 +/- 2 weeks after PTCA in 403 patients. From left ventricular angiography obtained before PTCA, regional dyskinesia was classified into anterior or posterior locations. Both patients with and without previous MI had a significant increase in exercise capacity from before to 2 and 20 weeks after PTCA (previous MI: 31.9% and 29.3%; no MI: 50.7% and 38.2%; p <0.0001 [analysis of variance]). In patients with MI and anterior dyskinesia, in whom lesions on the left anterior descending artery were dilated or posterior dyskinesia in whom lesions on the right coronary artery were dilated, exercise capacity increased significantly from before to 2 and 20 weeks after PTCA (left anterior descending artery: 53.1% and 39.7%, p <0.0001; right coronary artery: 16.9% and 27.6%, p = 0.01 [analysis of variance]). Multivariate regression analysis revealed that male sex, no previous MI, and dilation of left anterior descending artery were significantly associated with increased exercise capacity after angioplasty adjusted for age and smoking habits, whereas left ventricular ejection fraction and end-diastolic pressure were not associated with increased exercise capacity.  相似文献   

8.
Restenosis is a clinical problem after coronary angioplasty associated with major ischemic events or repeat interventions in 20-50% of the patients undergoing this procedure. Major efforts have been undertaken in the past decade to successfully prevent or treat restenosis but no pharmacologic approach to the problem has as yet been identified to be effective enough in clinical conditions. New strategies to cope with restenosis are targeted by local application of ionizing radiation which markedly reduces cell proliferation after angioplasty in animal experiments. Preliminary clinical trials indicate that endovascular radiation therapy is a safe and effective means to treat restenosis. Randomized, multicenter studies with long follow-up periods are needed to support these early results.  相似文献   

9.
OBJECTIVE: To study the hemorheological effects of Sini decoction on patients following percutaneous transluminal coronary angioplasty (PTCA). METHODS: Forty-six patients were randomly divided into Sini decoction and control groups. The hemorheologic variables were determined before and after Sini decoction treatment. RESULTS: No hemorheologic changes were observed in the patients (n = 23) only with PTCA, but the patients (n = 23) with Sini decoction were found to be significantly decreased in whole blood viscosity and red cell aggregation and dredging the blood of microcirculation as post-PTCA compared to pre-PTCA. CONCLUSION: Sini decoction could improve the patient's hemorheology.  相似文献   

10.
Foldable lenses represent a major breakthrough in the effort to achieve ever smaller incisions. The plate-haptic or "taco-style" lenses are folded and implanted by a device called an injector. Although customized for each manufacturer's lens, the injectors all have a common design principle: the intraocular lens (IOL) is folded within a funnel-like structure of the tip and is advanced by a plunger that pushes and delivers the lens. To maintain optimal hand stabilization and injector management, both hands are usually required. This does not leave a hand to help with IOL positioning. To improve handling, a simple, mechanized system has been created for a new injector system that allows the delivery of the plate-haptic lens with one hand, in a pen-like fashion.  相似文献   

11.
BACKGROUND: Acute myocardial infarction is caused by sudden thrombotic occlusion of the coronary artery due to a previous rupture of atherosclerotic plaque. OBJECTIVE: To use intracoronary ultrasound measurements to evaluate lumen and plaque changes in patients with acute myocardial infarction. METHODS: Patients (n = 103) with acute myocardial infarction who had been scheduled to undergo primary percutaneous transluminal coronary angioplasty (PTCA) were selected. Both before and after successful coronary angioplasty, intracoronary 30 MHz ultrasound studies were performed using a 3.5F monorail catheter. The ultrasound catheter was successfully advanced into the occluded vessel segment without major complications prior to PTCA in 79 of 103 (76.7%) patients and after PTCA in 88 of 103 (85.3%) patients. RESULTS: The plaques were eccentric in 66 patients (83.5%). The plaque morphology was purely low echogenic in 14 (17.7%), highly echogenic in six (7.6%) and mixed in 59 (74.7%) patients. Partial (59 of 79, 74.7%) or ring-like calcification (3 of 79, 3.8%) was observed in 62 patients (78.5%). Plaque fissuring or dissection was detected prior to PTCA in 25 patients (31.7%). Coronary angioplasty successfully enlarged the inner luminal area from 2.1 +/- 0.7 to 7.4 +/- 1.9 mm2 (P < 0.01), whereas the plaque-thrombus area decreased significantly (13.8 +/- 1.7 mm2 before and 9.0 +/- 1.9 mm2 after PTCA; P < 0.01). The total vessel area remained virtually constant (15.9 +/- 1.9 mm2 before and 16.4 +/- 2.5 mm2 after PTCA, NS). PTCA-induced plaque rupture or dissection was observed in only 13 (16.5%) patients. CONCLUSION: Intracoronary ultrasound imaging can be performed safely and successfully prior and subsequent to PTCA in selected patients with acute myocardial infarction. Early reperfusion via PTCA seems to be attributable to a significant reduction in the amount of low-echogenic plaque and thrombus material, whereas factors like balloon-induced dissection and stretching of vessels play only a minor role.  相似文献   

12.
BACKGROUND: Although the short-term and long-term beneficial effects of early coronary revascularization by primary PTCA or thrombolytic therapy have been established for acute myocardial infarction, thrombolytic therapy >24 hours after the onset of acute myocardial infarction has not been shown to improve clinical outcome. The purpose of this study was to assess the effect of late revascularization by primary PTCA over a 5-year period. METHODS AND RESULTS: Eighty-three patients with initial Q-wave anterior myocardial infarction >24 hours after onset were randomized into a PTCA group (n=44) and a no-PTCA group (n=39). Long-term follow-up was conducted with regard to end points, which included cardiac death, nonfatal recurrence of myocardial infarction, and development of congestive heart failure. Left ventricular ejection fraction and regional wall motion at 6 months after myocardial infarction were similar in the 2 groups. Left ventricular end-diastolic and end-systolic volume indexes were significantly smaller in the PTCA group than in the no-PTCA group (P<0.0001). With cardiac events as end points, a 5-year Kaplan-Meier event-free survival analysis revealed that the no-PTCA group had a worse prognosis than the PTCA group (P<0.0001). Patency of the infarct-related artery, left ventricular ejection fraction, end-diastolic volume index, and end-systolic volume index were significantly associated with cardiac events by a Cox proportional hazards analysis (hazard ratios 0.120, 0.845, 1.065, and 1.164, respectively). CONCLUSIONS: In initial Q-wave anterior myocardial infarction, we conclude that even with late reperfusion, PTCA had beneficial effects on cardiac events over the 5-year period after myocardial infarction, with the prevention of left ventricular dilation after myocardial infarction being a possible mechanism.  相似文献   

13.
A young woman with a large astigmatic refractive error obtained no visual improvement with glasses. Repeated manifest refractions revealed persistent variations in the apparent cylinder axis. A suitable choice of spectacle frames facilitated a satisfactory outcome. The pitfalls inherent in the clinical specification of cylinder axis, and the potential visual consequences, are discussed.  相似文献   

14.
Risk factors and outcomes associated with non-Q-wave myocardial infarction (MI) in diabetics and nondiabetics were analyzed for 376 consecutive patients, 77 with diabetes (20%) and 299 nondiabetics (80%), who had non-Q-wave MI and had percutaneous transluminal coronary angioplasty (PTCA) performed before discharge from hospital during the period from January 1992 to February 1996. Diabetics were slightly older (64 +/- 10 years vs 61 +/- 12 years, p <0.053), had more prior coronary artery bypass grafting (CABG) surgery (27% vs 12%, p <0.001), and hypertension (77% vs 49%, p <0.001). There was no significant difference in unstable angina, saphenous vein graft PTCA, single versus multiple vessel disease, or history of MI. PTCA success rates for diabetics versus nondiabetics were similar (96% vs 97%, p = NS). In-hospital complications such CABG, recurrent MI, repeat PTCA, stroke, and death were not statistically significant between the 2 groups. At 1-year follow-up, survival in diabetics (92%) was similar to nondiabetics (94%, p = NS), although event-free survival (PTCA, CABG, MI, death) was worse in diabetics (55% vs 67% for nondiabetics, p <0.05). Although diabetic patients with non-Q-wave MI represent a cohort with more risk factors for poor outcome, aggressive in-hospital revascularization with PTCA results in an excellent short-term outcome as well as 1-year survival similar to the nondiabetic patients. However, total events at 1-year follow-up are more common in the diabetic patients, suggesting that more aggressive screening and therapy in follow-up may be warranted, and that a diabetic with non-Q-wave MI will require increased utilization of cardiovascular resources in the first year after the event.  相似文献   

15.
Cyclopenta[cd]pyrene 3,4-oxide (2) has been synthesized in a one-step, quantitative reaction using dimethyldioxirane. The oxide, or its thermal rearrangement products cyclopenta[cd]-pyren-3(4H)-one and cyclopenta[cd]pyren-4(3H)-one, is formed from cyclopenta[cd]pyrene (1) under simulated environmental conditions. In one case these products are formed when 1 is adsorbed on model particulates and then exposed to the reaction products of tetramethylethylene and ozone in the gas phase.  相似文献   

16.
Numerous attempts have been made to prevent late restenosis after successful percutaneous transluminal coronary angioplasty (PTCA), but there is still no effective treatment. This report describes the effect of an oral lipid-lowering agent, pravastatin, on restenosis after successful PTCA. Sixty-six patients who underwent successful elective PTCA were assigned to a pravastatin-treated group (Group 1, n = 29) or an untreated group (Group 2, n = 37) in a prospective and randomized fashion. Pravastatin (5 mg or 10 mg twice a day) was given to Group 1 patients from day 3 after the procedure. Selective coronary angiography was repeated 3 to 5 months later, or sooner if the patient developed angina pectoris. The serum cholesterol level was decreased significantly in Group 1 (from 215.7 +/- 44.3 mg/dl to 181.2 +/- 30.3 mg/dl, p < 0.001), but not in Group 2 (from 191.9 +/- 30.8 mg/dl to 191.8 +/- 33.3 mg/dl, p = ns), at the time of repeat coronary angiography. However, there were no differences between the groups with regard to the recurrence of angina, the need for repeat PTCA, or restenosis, as assessed by quantitative analysis of coronary cineangiograms. These results suggest that oral pravastatin therapy does not effectively prevent late restenosis after successful PTCA by this mode of administration.  相似文献   

17.
PURPOSE: The aim of the study was to investigate the heart rate turn point (HRTP) in the time course of the heart rate performance curve (HRPC) in patients after myocardial infarction, and the relationship between the HRTP, the left ventricular function, and the second lactate turn point (LTP2). METHODS: We studied the degree and the direction of the HRPC and the left ventricular ejection fraction (LVEF) in 49 male patients 57 +/- 8 d after their first posterior wall infarction (MI). An incremental cycle ergometer test was performed and three phases of energy supply were defined (I: aerobic; II: aerobic-anaerobic transition; III: anaerobic) via blood lactate LA concentration. HRTP and LVEF-turn points (LVEFTP) were assessed by linear turn point analysis. The degree and direction of the deflection of HRPC were described as factor k (k > 0.1: downward deflection; -0.1 < k < 0.1: linear time curse; k < -0.1: upward deflection). The LVEF was determined by RNA. The difference between Pmax and LTP2 was calculated for LVEF (delta LVEF). RESULTS: An HRTP could be found in 44 and a LVEFTP in 47 cases. The HRTP occurred at 85 +/- 17 Watt (W), which correlated (r = 0.95; P < 0.001) with the LTP2 (84 +/- 17 W) and the LVEFTP (84 +/- 17 W, r = 0.93; P < 0.001). From LTP2 to Pmax a significant decrease in LVEF was found. There was a correlation between the percentage of HRmax at the HRTP and k (r = 0.70), as well as delta LVEF (r = 0.56). CONCLUSIONS: To prevent myocardial overloading, it seems to be useful to determine the HRTP, which indicate the workload where LVEF decreases.  相似文献   

18.
OBJECTIVES: We sought to study the safety, feasibility and efficacy of selective suction and pressure-regulated retroinfusion to protect against myocardial ischemia in patients undergoing normal risk and high risk balloon angioplasty. BACKGROUND: In a pig model of acute myocardial ischemia it was previously shown that use of selective suction and pressure-regulated retroinfusion was able to substantially preserve regional myocardial function during ischemia with a higher efficacy than that obtained with unselective synchronized retroperfusion. METHODS: In 42 patients with normal risk (n = 27) or high risk (n = 15) percutaneous transluminal coronary angioplasty (PTCA), alternate balloon inflations of the left anterior descending coronary artery (60 s) were either supported or not supported by selective suction and pressure-regulated retroinfusion of the anterior interventricular vein. In an additional group of 10 patients with normal risk, retroinfusion was directly compared with autoperfusion during 10 min of ischemia. RESULTS: Balloon inflations without retroinfusion resulted in a decrease of regional myocardial function in the ischemic zone to 13% of baseline. In contrast, regional myocardial function was preserved at 76% of baseline (p < 0.05) during balloon inflation supported by retroinfusion. This preservation of regional myocardial function by retroinfusion was maintained during 10 min of ischemia with at least similar efficacy compared with autoperfusion. With retroinfusion, hemodynamic variables were stabilized in normal risk and high risk patients. No complications related to the catheterization of the anterior interventricular vein using a femoral approach (95% success rate) were observed, and clinical follow-up after 3 to 6 months was uneventful with regard to the coronary intervention. CONCLUSIONS: Use of selective suction and pressure-regulated retroinfusion was feasible and safe and had a high efficacy for preserving regional myocardial function and hemodynamic variables during PTCA in normal risk and selected high risk patients.  相似文献   

19.
Several studies have demonstrated substantial risk reduction by risk factor modification in patients with established coronary artery disease. The number of studies investigating the implementation of risk factor intervention in clinical practice, however, is limited. We have, therefore, recorded drug use and cardiovascular risk factors in all 148 patients who had undergone percutaneous coronary angioplasty (PTCA) in 1989 at the University Hospital, Zurich, on hospital admission, after 6 months and 5 years later. Most patients had antithrombotic treatment with little change over time (78%, 87% and 83% on admission, after 6 months and after 5 years respectively, p = 0.27). The use of beta-blockers decreased moderately after 5 years (73%, 81% and 61% respectively, p < 0.01). Calcium channel blockers were used frequently without significant change in the follow-up period (56%, 50% and 46%, p = 0.25). Five years after PTCA, 91% of patients with a history of hypertension were on antihypertensive drugs. The use of lipid-lowering drugs increased markedly (5%, 16% and 33% respectively, p < 0.01). However, only a small proportion of patients qualifying for lipid-lowering drugs according to Swiss guidelines were treated. The proportion of current smokers decreased from 26% on hospital admission in 1989 to 12% in 1994. We conclude that in our study population secondary prevention was generally satisfactorily implemented. However, better monitoring and treatment of increased lipid levels is mandatory.  相似文献   

20.
The genotoxic activities of 8-methoxypsoralen (8-MOP) and 4,4',5'-trimethylazapsoralen (4,4',5'-TMAP) on plasmid DNA have been compared. In a previous work, 4,4',5'-TMAP, a methyl derivative of a psoralen isoster, had shown potential photochemotherapeutic activity. The mutagenic activity of mono- and bifunctional lesions caused by these compounds was evaluated both after UVA irradiation, which causes the formation of both kinds of lesions, and after a two-step irradiation procedure of the psoralen-plasmid DNA complex, which allowed monoadducts and interstrand crosslinks to be studied separately. Furthermore, we used a procedure that allowed us to evaluate both the mutagenic and recombinogenic activity of the two compounds. Results indicate that the most important difference between 8-MOP and 4,4',5'-TMAP consists in their mode of photoreaction with DNA rather than in their mutagenic potential. In fact, in all of the experimental procedures, 4,4',5'-TMAP shows a lower ability than 8-MOP to generate interstrand crosslinks. However, when comparable toxicity levels are reached, the two compounds show the same mutagenic potentiality.  相似文献   

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