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Although many patients with restenosis after balloon coronary angioplasty have recurrence of angina, others remain asymptomatic. To assess the clinical implications of asymptomatic coronary restenosis, we analyzed clinical and angiographic characteristics of 277 consecutive patients with restenosis, 133 (48%) of whom were asymptomatic (group I) and 144 (52%) symptomatic (group II). Restenosis was documented 6 to 9 months after the index procedure, or earlier if angina recurred, and was defined as a greater than 50% lumen narrowing (visual estimation). Group I (asymptomatic group) included fewer female (9% vs. 18%, p less than 0.05) and hypertensive patients (38% vs. 56%, p less than 0.005) and more patients with a previous myocardial infarction (48% vs. 28%, p less than 0.05) and single-vessel disease (67% vs. 55%, p less than 0.05). Before angioplasty, symptoms had lasted for a shorter period (10 +/- 25 vs. 23 +/- 42 months, p less than 0.001), ischemia after a recent infarction was a more frequent indication (21% vs. 10%, p less than 0.05) and total revascularization more frequently obtained (74% vs. 63%, p less than 0.05) in group I than in group II patients. Only a normal blood pressure, previous myocardial infarction, single-vessel disease and a shorter duration of symptoms were independent correlates of asymptomatic restenosis. No differences were found in stenosis severity before angioplasty (90% in both groups) or after angioplasty (22% +/- 12% vs. 24% +/- 16%).(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
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The incidence of restenosis remains the same as initially reported (30%) and no therapeutic approach has reduced its appearance. Platelets-induced smooth muscle cell proliferation probably play a preponderant role in the pathogenesis of restenosis. The aim of this study was to evaluate the effects of ticlopidine (250 mg/day) on restenosis rate after single lesion coronary angioplasty. One hundred seventy nine consecutive patients were prospectively included in this study and were assigned to ticlopidine (group T, n = 91) or to a control group (n = 88) in an alternative fashion. Age (60 +/- 10 vs 58 +/- 9 years), gender (87% vs 87% male), treatment, coronary risk factors, lesion morphology, stenosis severity pre- and postangioplasty, type of vessel, collateral circulation, and left ventricular ejection fraction, were similar in the T and control groups, respectively. Unstable angina was more frequently found in group T patients (81% vs 65%, p less than 0.01). A late angiographic follow-up (7 +/- 2 months after angioplasty) revealed restenosis (greater than 50% luminal narrowing) in 26 patients (28%) in group T and in 21 patients (24%) in the control group (NS). At that time, 88% and 98% of patients without restenosis vs 35% and 48% of patients with restenosis were asymptomatic in the T and control groups, respectively. An exercise test prior to the late control angiogram was abnormal (angina and/or ST segment depression) in 77% and 73% of patients with restenosis in T and control groups, respectively. Thus, in our experience, ticlopidine at a dosage of 250 mg/day was unable to reduce restenosis rate after single lesion coronary angioplasty.  相似文献   
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Background and hypothesis: The purpose of this study was the comprehensive evaluation of the changes in pulmonary venous and mitral flow velocities of patients with acute and chronic severe aortic regurgitation. Transmitral flow velocities obtained with pulsed-wave Doppler echocardiography have been used to provide information on left ventricular (LV) filling and diastolic function. Pulmonary venous flow tracings are an important adjunct to LV inflow pattern in assessing LV diastolic function. Methods: Fourteen patients with severe aortic regurgitation (8 chronic and 6 acute) and in sinus rhythm were examined by transthoracic and transesophageal pulsed Doppler echocardiography. Mitral and pulmonary flow velocities were recorded and compared. All patients had ejection fractions > 40%. Results: Early mitral flow peak velocity was higher in patients with acute regurgitation (p<0.001). The mitral A wave was absent in five patients with acute regurgitation. In contrast, a prominent reverse atrial pulmonary systolic wave AR was demonstrated in these patients. Peak diastolic velocity of the pulmonary venous flow was greater in patients with acute aortic regurgitation (0.76 ± 0.13) than in patients with chronic aortic regurgitation (0.40 ± 0.09) (p<0.001). Peak systolic velocity did not differ significantly between the two groups. The systolic fraction of pulmonary venous flow in patients with acute aortic regurgitation was lower (0.43 ± 0.05) than that of patients with chronic regurgitation (0.63 ± 0.1) (p<0.01). All patients with acute aortic regurgitation had an S/D ratio < 1, while those with chronic regurgitation had an S/D >1 (p< 0.001) and an E/A<1. Conclusion: Patients with severe acute aortic regurgitation showed a retrograde atrial kick (absence of transmitral A wave with prominent pulmonary AR wave). These patients had an S/D ratio < 1 (restrictive Doppler pattern). Patients with chronic aortic regurgitation exhibited a Doppler pattern of abnormal LV relaxation (E/A <1, S/D > 1).  相似文献   
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