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N Danchin

Publications and source records attributed to N Danchin.

At least 19 recordsLinked to original sources
PubMed1998

Impact of intravascular ultrasound guidance in stent deployment on 6-month restenosis rate: a multicenter, randomized study comparing two strategies--with and without intravascular ultrasound guidance. RESIST Study Group. REStenosis after Ivus guided STenting.

OBJECTIVES: We aimed to investigate the impact of intravascular ultrasound (IVUS)-guided stent implantation on the 6-month restenosis rate, which has not yet been fully established in randomized trials. BACKGROUND: The 6-month angiographic restenosis rate was compared in patients with symptomatic ischemic heart disease who were randomly allocated to angioplasty and stent deployment, with versus without IVUS guidance. METHODS: After successful stent implantation, patients were randomized into two groups: Group A had no further dilation, and Group B had additional balloon dilation until achievement of IVUS criterion for stent expansion. The study group consisted of 164 patients, assuming a 50% reduction of the restenosis rate in Group B (15% vs. 30%) (alpha = 10%, beta = 20%). RESULTS: We enrolled 155 patients. Overdilation was carried out in 31 (39%) of 79 Group B patients, with the IVUS criterion being achieved in 63 (80%) of 79. No significant difference was observed in the minimal luminal diameter (MLD), but the stent lumen cross-sectional area (CSA) was significantly larger in Group B (mean +/- SD) (7.16 +/- 2.48 vs. 7.95 +/- 2.21 mm2, p = 0.04). At 6 months, there was no significant difference in the restenosis rate, (28.8% [21 of 73] in Group A vs. 22.5% [16 of 71] in Group B, p = 0.25), but according to the observed difference in the restenosis rate, the power of the study was only 40%. The difference in MLD was also nonsignificant (1.60 +/- 0.65 mm in Group A vs. 1.70 +/- 0.64 mm in Group B, p = 0.20), whereas the lumen CSA was 20% larger in the IVUS-guided group (4.47 +/- 2.59 vs. 5.36 +/- 2.81 mm2, p = 0.03). Lumen CSA was the only predictor of restenosis by multivariate logistic regression analysis. CONCLUSIONS: A nonsignificant 6.3% absolute reduction in the restenosis rate and a nonsignificant difference in MLD were observed in this study. Nonetheless, we still cannot rule out a beneficial effect of IVUS guidance, although this may have gone undetected owing to a lack of statistical power. A significant increase was observed in immediate and 6-month lumen size, as detected by IVUS, indicating that ultrasound guidance in stent deployment may be beneficial.

Angioplasty, Balloon, Coronary↗
PubMed1997

Assessment of myocardial viability in patients with previous myocardial infarction by using single-photon emission computed tomography with a new metabolic tracer: [123I]-16-iodo-3-methylhexadecanoic acid (MIHA). Comparison with the rest-reinjection thallium-201 technique.

OBJECTIVES: We compared the ability of rest single-photon emission computed tomography (SPECT) with [123I]-16-iodo-3-methylhexadecanoic acid (MIHA) and the thallium-201 (Tl-201) rest-reinjection technique to detect myocardial viability after infarction. BACKGROUND: After myocardial infarction, MIHA frequently shows increased uptake in the areas with exercise Tl-201 defects (mismatch), even in patients with an irreversible Tl-201 reinjection defect. Whether such increased uptake is indicative of ischemic but viable myocardium is not known. METHODS: We studied 38 patients who 1) underwent exercise SPECT Tl-201 with rest-reinjection and rest SPECT with MIHA before undergoing percutaneous transluminal coronary angioplasty (PTCA) of an infarct-related coronary artery, and 2) were found to have successful revascularization at follow-up angiography. The relation between SPECT results before PTCA and subsequent improvement in left ventricular wall motion was assessed. RESULTS: A mismatch was evident before PTCA in 51 of 76 infarct-related segments and correlated with subsequent improvement in wall motion (overall accuracy 71%), even for the 27 segments whose exercise defects remained irreversible after Tl-201 reinjection (overall accuracy 81%). The finding of a mismatch clearly enhanced the results provided by the finding of > or = 50% Tl-201 uptake as determined at redistribution (p < 0.05), but not as determined at reinjection, although there was a trend toward a better specificity for the findings of a mismatch. CONCLUSIONS: MIHA is an efficient marker of viability inside exercise-underperfused areas after infarction, even in patients with irreversible Tl-201 reinjection defects. Assessment by conventional SPECT of a mismatch between results obtained with a metabolic tracer (MIHA) and a flow tracer analyzed at exercise (Tl-201) as a marker of myocardial viability is a promising area of research.

Adult↗
PubMed1997

D allele of the angiotensin I-converting enzyme is a major risk factor for restenosis after coronary stenting.

BACKGROUND: Although intracoronary stent implantation significantly reduces restenosis compared with balloon angioplasty, a minority of patients still develop restenosis predominantly due to neointimal hyperplasia. Experimental studies suggest that the renin-angiotensin system is involved in neointimal hyperplasia after arterial injury. In humans, the plasma and cellular levels of ACE are associated with an I/D genetic polymorphism in the ACE gene, DD patients having higher levels. METHODS AND RESULTS: We investigated a possible relation between the ACE I/D polymorphism and restenosis in 146 patients who underwent successful implantation of a Palmaz-Schatz stent and had 6-month follow-up angiography. The minimal lumen diameter (MLD) before and after the procedure did not differ significantly among the three groups of genotypes (DD, ID, and II). At follow-up, MLD had a significant inverse relationship to the number of D alleles present (DD, 1.65 +/- 0.71 mm; ID, 1.84 +/- 0.60 mm; II, 2.05 +/- 0.61 mm; P < .007). Late luminal loss during the follow-up period was significantly related to the number of D alleles (DD, 0.89 +/- 0.61 mm; ID, 0.60 +/- 0.52 mm; II, 0.40 +/- 0.53 mm; P < .0001). The relative risk of restenosis (defined as a > 50% diameter stenosis at follow-up) approximated by the adjusted odds ratio was 2.00 per number of D alleles (95% confidence interval, 1.03 to 3.88, P < .04). CONCLUSIONS: The ACE I/D polymorphism influences the level of late luminal loss after coronary stent implantation. These results suggest that the renin-angiotensin system may be implicated in the pathogenesis of restenosis after coronary stenting.

Aged↗
PubMed1997

Changes in immediate outcome of percutaneous transluminal coronary angioplasty in multivessel coronary artery disease in 1990 to 1991 versus 1994 to 1995.

Coronary angioplasty has undergone major technical changes since the period of inclusion in the randomized trials, comparing it with surgery, particularly with the increased use of coronary stents. This study shows improved in-hospital outcome in terms of primary success and complication rates in patients treated with coronary angioplasty for multivessel disease from 1994 to 1995, compared with the 1990 to 1991 period.

Aged↗
PubMed1997

[Circadian rhythm in myocardial infarct in France. Results of the USIK study].

OBJECTIVES: To analyze the circadian pattern of the first signs of myocardial infarction in France. METHODS: The USIK study was conducted in November 1995 among patients hospitalized in cardiac intensive care units within 48 hours after the first signs of confirmed myocardial infarction. This prospective study recorded the day and hour of onset for each eligible patient. RESULTS: Three hundred seventy-three centers throughout France participated, including 2563 patients (71% men), mean age 68 years, with confirmed myocardial infarction. The day of the week in which the first signs occurred was recorded between November 3 and 30, 1995. The pattern did not show any peaks, notably on Monday as reported in the literature. The hour of onset was known in 2468 patients (96.3%). Demographic features and past history did not vary for the overall population. Hour of onset was: between midnight and 6 a.m. 20.1%; between 6 and 12 a.m. 30.6%; between noon and 6 p.m. 25.7%; between 6 p.m. and midnight 23.6% (p < 0.001). This pattern was also studied in several subgroups of patients defined by age, sex, presence or absence of different cardiovascular risk factors or pertinent cardiovascular history. Univariate analysis showed that the distribution in the 6 a.m.-noon period was significantly different by age group. Older patients had a higher morning peak than younger patients (32.6% versus 28.7%; p = 0.03). Inversely, this peak was lower in smokers compared with non-smokers (26.7% versus 32.4%; p = 0.005); likewise, in patients with recurrent infarction compared with first infarction patients (24.7% versus 31.9%; p = 0.003). Other variables did not affect the circadian pattern. After multivariate analysis, only 2 of these 3 factors had an influence on distribution in the 6-12 a.m. period: smoking habits (odds ratio = 0.75; p < 0.01) and prior myocardial infarction (odds ratio = 0.70; p < 0.01). CONCLUSION: This large epidemiology study confirms that there is a morning peak in the circadian pattern of myocardial infarction in France. Smoking and past history of infarction significantly affect the circadian pattern.

Aged↗
PubMed1997

Incomplete bundle-branch block and ST-segment elevation: syndrome associated with sustained monomorphic ventricular tachycardia in patients with apparently normal heart.

This paper reports on three cases of patients with an apparently normal heart admitted for sustained monomorphic ventricular tachycardia. The only abnormal finding showed in the electrocardiogram (ECG) in sinus rhythm that exhibited an entity associated with incomplete right bundle-branch block and persistent ST-segment elevation. The ECG entity was variable and disappeared transiently. Spontaneous ventricular tachycardia in one patient was inducible by programmed stimulation. There was no underlying heart disease. The origin of the ventricular tachycardia in one patient was located by pace mapping in the left ventricle at the left ventricular basal septum. The follow-up (from 6 months up to 6 years) demonstrated a good prognosis. This particular ECG entity associated with monomorphic ventricular tachycardia could have been missed because of the variations in the ECG in sinus rhythm and was associated with a favorable prognosis.

Adult↗
PubMed1997

Diagnostic value of exercise electrocardiography and angina after coronary artery stenting. Benestent Study Group.

To determine whether metallic stent implantation within a coronary artery modifies the accuracy of angina or exercise test results in predicting stenosis, we studied 172 patients assigned to stent implantation and 153 patients assigned to balloon angioplasty enrolled in the Benestent trial comparing de novo stenting with conventional balloon angioplasty. Sensitivity and specificity curves were constructed for the prediction of percentage diameter stenosis and minimal lumen diameter. Receiver-operator curves were constructed for comparison of diagnostic accuracy. Identical exercise load and duration were achieved in the two groups, despite a better angiographic result in patients treated with a stent. Similarly, the diagnostic accuracy of clinical symptoms or exercise test results as a function of the angiographic results were similar in patients with and patients without a stent. The intersection points of the sensitivity and specificity curves for recurrent angina or ST-segment depression were 72% to 77%. The corresponding cut-off points for percentage diameter stenosis were, respectively, 52% and 50% for patients with and without a stent (1.35 and 1.50 mm for minimal lumen diameter). We conclude that the presence of an intracoronary stent does not affect the diagnostic accuracy of recurrent angina or exercise-induced ST depression in predicting residual stenosis. We also conclude that exercise tolerance is similar after balloon angioplasty, with or without stenting, despite a better angiographic outcome in the group receiving a stent, suggesting a minimal threshold beyond which the patient is no longer at risk for ischemia during exercise.

Angina Pectoris↗
PubMed1997

Effect of pravastatin on angiographic restenosis after coronary balloon angioplasty. The PREDICT Trial Investigators. Prevention of Restenosis by Elisor after Transluminal Coronary Angioplasty.

OBJECTIVES: This study sought to determine whether pravastatin affects clinical or angiographic restenosis after coronary balloon angioplasty. BACKGROUND: Experimental data and preliminary clinical studies suggest that lipid-lowering drugs might have a beneficial effect on restenosis after coronary angioplasty. METHODS: In a multicenter, randomized, double-blind trial, 695 patients were randomized to receive pravastatin (40 mg/day) or placebo for 6 months after successful balloon angioplasty. All patients received aspirin (100 mg/day). The primary angiographic end point was minimal lumen diameter (MLD) at follow-up, assessed by quantitative coronary angiography. A sample size of 313 patients per group was required to demonstrate a difference of 0.13 mm in MLD between groups (allowing for a two-tailed alpha error of 0.05 and a beta error of 0.20). To allow for incomplete angiographic follow-up (estimated lost to follow-up rate of 10%), 690 randomized patients were required. Secondary end points were angiographic restenosis rate (restenosis assessed as a categoric variable, > 50% stenosis) and clinical events (death, myocardial infarction, target vessel revascularization). RESULTS: At baseline, clinical, demographic, angiographic and lipid variables did not differ significantly between groups. In patients treated with pravastatin, there was a significant reduction in total and low density lipoprotein cholesterol and triglyceride levels and a significant increase in high density lipoprotein cholesterol levels. At follow-up the MLD (mean +/- SD) was 1.47 +/- 0.62 mm in the placebo group and 1.54 +/- 0.66 mm in the pravastatin group (p = 0.21). Similarly, late loss and net gain did not differ significantly between groups. The restenosis rate (recurrence > 50% stenosis) was 43.8% in the placebo group and 39.2% in the pravastatin group (p = 0.26). Clinical restenosis did not differ significantly between groups. CONCLUSIONS: Although pravastatin has documented efficacy in reducing clinical events and angiographic disease progression in patients with coronary atherosclerosis, this study shows that it has no effect on angiographic outcome at the target site 6 months after coronary angioplasty.

Adult↗
PubMed1997

Management of acute myocardial infarction in intensive care units in 1995: a nationwide French survey of practice and early hospital results.

OBJECTIVES: This survey sought to determine actual practices in the management of acute myocardial infarction on a nationwide scale. BACKGROUND: Few data are available regarding the adoption of clinical trial results of treatment of myocardial infarction into "real-world" clinical practice. METHODS: Of 501 intensive care units in France, 373 (74%) collected data from all patients with myocardial infarction admitted within 48 h of symptom onset during November 1995. RESULTS: Data from 2,563 patients (71% men; mean age [+/-SD] 67 +/- 14 years) were included. Time from symptom onset to admission was <6 h in 1,467 patients (62%). Thrombolysis was used in 822 patients (32%) and primary angioplasty in 330 (13%). The use of reperfusion therapy decreased markedly with age. During the first 5 days, heparin was prescribed in 96% of patients, aspirin in 89%, nitrates in 87%, beta-adrenergic blocking agents in 64%, angiotensin-converting enzyme inhibitors in 46% and calcium antagonists in 17%. Coronary angiography was performed in 33% of patients, and 58% had echocardiographic assessment of left ventricular ejection fraction (LVEF). Median LVEF was 50%. The 5-day mortality rate was 7.7% compared with 12.1% in a previous French survey carried out in 1984. By multivariate analysis, independent predictors of mortality were age, anterior infarction, history of stroke and heart failure and, when added to the model, Killip class and LVEF. CONCLUSIONS: This survey shows that the results of therapeutic trials have largely translated to clinical practice, resulting in improved early outcome compared with the early 1980s. However, continuous efforts should be made to shorten the time delay before hospital admission and to increase the proportion of elderly patients receiving reperfusion therapy.

Aged↗
PubMed1997

Additional predictive value of both left and right ventricular ejection fractions on long-term survival in idiopathic dilated cardiomyopathy.

BACKGROUND: In idiopathic dilated cardiomyopathy, long-term outcome is poor and left ventricular ejection fraction is a major powerful predictor of survival. However, right ventricular function might also play an important role in the long-term prognosis of this disease. AIM: The aim of this study was to determine the role of right ventricular parameters, mainly right ventricular ejection fraction, on survival in idiopathic cardiomyopathy. METHODS: We prospectively assessed long-term follow-up and predictors of survival in 62 consecutive patients referred from 1990 to 1992 for evaluation of idiopathic dilated cardiomyopathy, including haemodynamic evaluation, thermodilution right ventricular ejection fraction and volume measurements. RESULTS: At the time of catheterization, dyspnoea class III or IV was present in 60% of the patients, atrial fibrillation in 19% and complete left bundle branch block in 35%. Left ventricular ejection fraction was 30 +/- 10% and right ventricular ejection fraction was 30 +/- 16%. During follow-up (2.2 +/- 1.3 years), 15 patients (24%) had heart transplantation and nine (14%) died before cardiac transplantation. Cumulative survival rate without heart transplantation was 74% and 56% at 1 and 4 years, respectively. In univariate analysis, survival was related to: dyspnoea class I or II (P < 0.04), absence of complete left bundle branch block (P < 0.05), administration of lower doses of furosemide (P < 0.01), high left ventricular ejection fraction (P < 0.001), low pulmonary artery pressure (P < 0.002), high cardiac index (P < 0.006), and low right ventricular volumes (P < 0.001). Multivariate analysis showed only two independent predictors of survival: left ventricular ejection fraction (P < 0.001) and right ventricular ejection fraction (P < 0.004). CONCLUSION: In addition to left ventricular ejection fraction, right ventricular ejection fraction appears to be a complementary predictor of survival in idiopathic dilated cardiomyopathy, suggesting the importance of assessing right ventricular function in this disease.

Adult↗
PubMed1997

Clinical and bacteriological characteristics of infective endocarditis in the elderly.

OBJECTIVE: To determine the clinical and bacteriological features of infective endocarditis in the elderly. DESIGN: Prospective case series. SETTING: A university hospital that is both a referral and a primary care centre. PATIENTS: 114 consecutive patients treated for infective endocarditis from November 1990 to December 1993: 25 were > 70 years of age (group 1) and 89 were < 70 years old (group 2). RESULTS: Location of infective endocarditis, clinical signs, and symptoms were similar in the two groups, except for a lower occurrence of embolic episodes in the elderly (group 1:8%, group 2: 28%; P < 0.04). A higher rate of infective endocarditis on intracardiac prosthetic devices was noted in group 1 (group 1: 52%, group 2: 25%; P < 0.05). The distribution of causative micro-organisms showed a higher proportion of bacteria from the gastrointestinal tract in the elderly (group D streptococci and enterococci: 48% in group 1 v 20% in group 2) and the presumed portal of entry was more often digestive (group 1: 50%, group 2: 17%; P = 0.01). Elderly patients were less often operated on (group 1: 24%, group 2: 43%; P = 0.07) and their mortality rate was higher (group 1: 28%, group 2: 13%; P = 0.08). CONCLUSIONS: Infective endocarditis in patients over 70 often occurs in those with intracardiac prosthetic devices and is more often due to bacteria from the gastrointestinal tract. Its prognosis appears to be worse than in younger subjects.

Adult↗
PubMed1997

[Quinidine and high-amplification ECG].

High-amplification ECG (HA ECG) is now used routinely to evaluate ventricular tachycardia. The effects of 300 to 600 mg quinidine were determined in 26 heart disease patients with spontaneous and inducible ventricular tachycardia. Programmed ventricular stimulation was performed and an HA ECG recorded (40 Hz high-pass filter) before and under treatment. The stimulation became negative under treatment in nine patients (group I), whereas the 17 others had persistent inducible tachycardia (group II). HA ECG tracings were modified in groups I and II, with a QRS duration increase of 7% and 8%, respectively, and RMS 40 decrease of 37% and 29%, and an LAS increase of 16% and 17%. Furthermore, one of the three group I and four of the seven group II patients who had a normal HA ECG tracing before treatment developed HA ECG abnormalities under treatment. An arrhythmia-inducing effect of the treatment was noted in three group II patients; this effect was not detected by HA ECG. In conclusion, changes in HA ECG tracings were seen during quinidine therapy of patients with ventricular tachycardia, and this effect was independent from the effect of antiarrhythmic agents on induction of the ventricular tachycardia. In addition, abnormalities of high-amplification ECG tracings developed in some patients under quinidine therapy. These data suggest that class I antiarrhythmic agents modify high-amplification ECG tracings and that these modifications fail to predict whether the treatment will prove effective.

Adult↗
PubMed1997

[Possible mechanisms of false positive results of averaged ECG].

UNLABELLED: The objective of this retrospective study was to investigate the causes of high amplification (HA) ECG abnormalities detected in apparently healthy subjects. This study was based on 14 patients derived from a population of 167 admitted for assessment of malaise or supraventricular tachycardia and who had no apparent heart disease. The surface ECG showed fine QRS complexes (< 120 ms) with no left hemiblock on ECG. All of these subjects underwent a complete electrophysiological study and high amplification ECG using a 40 Hertz high-pass filter. For these 14 patients, the amplitude of the last 40 milliseconds (ms) of the mean QRS (RMS 40) was less than or equal to 20 microvolts (microV). Eight of them also had a duration of the terminal part of the QRS complex less than 40 microV (LAS) greater than 40 ms and 6 others had and LAS greater than 35 ms. The mean QRS interval was normal in all patients (< 120 ms). The usual causes for reduction of the RMS 40-were eliminated: programmed ventricular pacing using 3 extrastimuli under basal conditions and with isuprel remained negative. E chocardiography and the right ventricular angiography were normal. The surface ECG showed slight abnormalities: absence of Q wave in V6 without delay of the intrinsic-like deflection in 3 subjects, increased R wave in V1 in 2 subjects and especially deep S wave in V5-V6 with no left axis deviation in 10 patients. Programmed or increasing frequency atrial pacing induced RBB or LBB in 13 of these 14 subjects (RBB: 7, LBB : 3, RBB and LBB:3). Follow-up, ranging from 6 months to 3 years, did not reveal any cardiac events, but signs of RBB appeared in 3 patients and signs of LBB were observed in 1 patient. IN CONCLUSION: an abnormal high amplification ECG in apparently healthy subjects could be explained by minor conduction disorders essentially in the right branch. The presence of a deep S wave (> 2 mm) in V5-V6 is the commonest ECG sign in these subjects. This diagnosis can only be proposed after exclusion of right ventricular dysplasia in symptomatic patients.

Adult↗