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D Himbert

Publications and source records attributed to D Himbert.

At least 37 records · Page 2Linked to original sources
PubMed1998

Efficacy of streptokinase, but not tissue-type plasminogen activator, in achieving 90-minute patency after thrombolysis for acute myocardial infarction decreases with time to treatment. PERM Study Group. Prospective Evaluation of Reperfusion Markers.

OBJECTIVES: We sought to examine the relation between time to treatment and 90-min patency rates in patients receiving intravenous streptokinase (SK) or accelerated tissue-type plasminogen activator (t-PA). BACKGROUND: Early patency of the infarct-related artery is a major determinant of survival after thrombolysis for acute myocardial infarction. Some data suggest that time to treatment may influence the efficacy of nonfibrin-specific thrombolytic agents in restoring early patency of the infarct-related vessel. METHODS: We performed a retrospective analysis of a cohort of 481 patients receiving thrombolytic therapy for acute myocardial infarction <6 h after pain onset, all of whom underwent 90-min coronary angiography. Patency of the infarct-related artery was graded by two observers who had no knowledge of the treatment received or the time between pain and therapy. RESULTS: There was no difference in baseline clinical or angiographic characteristics according to the timing or nature of treatment. Thrombolysis in Myocardial Infarction (TIMI) flow grade 2 or 3 patency rate after SK correlated negatively with the time between onset of pain and thrombolysis (r = 0.8, p = 0.05), whereas the 90-min patency rate after t-PA appeared stable as a function of time to treatment. When patients were categorized as having received treatment <3 or > or = 3 h after pain onset, the patency rate was similar with t-PA, but significantly higher when SK was administered early rather than late, regardless of whether TIMI flow grades 2 and 3 were pooled (86.9% vs. 59.4%, p = 0.0001) or TIMI flow grade 3 alone was considered to indicate patency (81.7% vs. 53.6%, p = 0.0001). Multivariate logistic regression analysis showed a negative effect of time to treatment on the patency probability for SK (p = 0.0001) but not for t-PA. CONCLUSIONS: The efficacy of streptokinase but not t-PA in restoring early coronary patency after intravenous thrombolysis is markedly lower when patients are treated later after onset of pain.

Coronary Angiography↗
PubMed1998

Hospital outcome after bailout coronary stenting in patients with acute myocardial infarction.

We evaluated the outcome of bailout coronary stenting in acute myocardial infarction. Fifty patients (35 men, mean age 60 plusmn; 12) with acute myocardial infarction consecutively underwent bailout stenting after primary and rescue coronary angioplasty (n=41 and 9, respectively). Cardiogenic shock was present in six patients, and 17 others had contraindications to thrombolysis. Stent implantation was successful in 49/50 patients. The antithrombotic regimen combined heparin, aspirin, and ticlopidine. One patient had symptomatic stent closure. Predischarge angiography in 41/44 survivors showed widely patent stents in 40/41 patients. Six patients (4 of whom had been admitted with cardiogenic shock) died in the hospital. During acute myocardial infarction, bailout stenting can achieve high TIMI grade 3 coronary patency (here, 92%), and low acute stent closure rates (here, 2%). However, in-hospital mortality remained high, at nearly 10%, mainly due to the severe risk profile in this patient subset.

Adult↗
PubMed1997

Revascularization of patients with unstable coronary artery disease: the case for early intervention.

In unstable angina, there are data to suggest a substantial risk of recurrent ischemia, infarction, and death when early angiography and/or revascularization have been deferred. Conversely, it has been suggested that early angiography and revascularization are more dangerous than deferred procedures. Critical review of the literature, however, suggests that there is no specific risk inherent in early intervention, but rather that patients who cannot wait are at higher risk anyway. The most valuable data on the comparison of an "early invasive" and a "conservative" strategy in unstable angina come from the Thrombolysis in Myocardial Ischemia (TIMI) IIIB study. The results show no major difference in outcome between groups (despite a high intervention rate in the conservative group), but a shorter hospital stay, lower drug use, and fewer rehospitalizations in the group treated according to the early invasive strategy. These results have been interpreted as favoring early intervention, due to the potential for a shorter hospital stay (a major determinant of cost in many countries) because of the possibility of achieving complete diagnosis and treatment within several days of admission, with good results. In addition, since the inception of the TIMI IIIB study, there have been major improvements in the field of angioplasty, such as the increased use of stents and the availability of safe and effective glycoprotein (GP) IIb-IIIa inhibitors. Thus, the pathophysiology, the excellent results of early intervention, and the recent improvements in angioplasty and its medical and pharmacologic environment, provide a strong rationale for early intervention.

Angioplasty, Balloon, Coronary↗
PubMed1997

Conservative management of patients with acute myocardial infarction and spontaneous acute patency of the infarct-related artery.

The role of systematic emergency percutaneous transluminal coronary angioplasty (PTCA) in patients with spontaneous reperfusion during myocardial infarction is debated. We retrospectively examined the inhospital outcome of 47 consecutive patients with myocardial infarction < 6 hours and angiographically proven spontaneous patency of the infarct artery managed without initial PTCA. There was one death (2.1%) and no incidence of reinfarction. Predischarge angiography showed regression of the culprit coronary lesion to < 50% stenosis in 23% of the patients, therefore obviating the need for PTCA. However, 17% of the patients had acute recurrent ischemia, requiring emergency intervention in 10.6%. Comparison with matched patients in whom Thrombolysis in Myocardial infarction grade 3 patency was achieved by thrombolysis or by primary PTCA showed that patients with spontaneous patency tended to have smaller infarctions, as judged from a lower peak creatine kinase level (1132 +/- 1002, 2051 +/- 1536, and 2715 +/- 2146 i.u., respectively; p = 0.001) and a higher left ventricular ejection fraction (56.4%, 47.9%, and 48.7% respectively; p = 0.02). In conclusion, these patients have an excellent inhospital outcome, with evidence of less myocardial damage than in patients in whom reperfusion therapy was required to achieve TIMI 3 patency. Initial conservative treatment appears safe.

Aged↗
PubMed1997

Can we provide reperfusion therapy to all unselected patients admitted with acute myocardial infarction?

OBJECTIVES: This study sought to assess the maximal rate of acute Thrombolysis in Myocardial Infarction (TIMI) grade 3 patency that can be achieved in unselected patients. BACKGROUND: Early and complete (TIMI grade 3 flow) reperfusion is an important therapeutic goal during acute myocardial infarction. However, thrombolysis, although widely used, is often contraindicated or ineffective. The selective use of primary and rescue percutaneous transluminal coronary angioplasty (PTCA) may increase the number of patients receiving reperfusion therapy. METHODS: A cohort of 500 consecutive unselected patients with acute myocardial infarction were prospectively treated using a patency-oriented scheme: Thrombolysis-eligible patients received thrombolysis (n = 257) and underwent 90-min angiography to detect persistent occlusion for treatment with rescue PTCA. Emergency PTCA (n = 193) was attempted in patients with contraindications to thrombolysis, cardiogenic shock or uncertain diagnosis and in a subset of patients admitted under "ideal conditions." A small group of patients (n = 38) underwent acute angiography without PTCA. Conventional medical therapy was used in 12 patients with contraindications to both thrombolysis and PTCA. RESULTS: Ninety-eight percent of patients received reperfusion therapy (thrombolysis, PTCA or acute angiography), and angiographically proven early TIMI grade 3 patency was achieved in 78%. Among patients with TIMI grade 3 patency, thrombolysis alone was the strategy used in 37%, emergency PTCA in 40% and rescue PTCA after failed thrombolysis in 15%; spontaneous patency occurred in 8%. CONCLUSIONS: Reperfusion therapy can be provided to nearly every patient (98%) with acute myocardial infarction. Rescue and direct PTCA provided effective early reperfusion to patients in whom thrombolysis failed or was excluded.

Adult↗
PubMed1997

Sex-related differences in eligibility for reperfusion therapy and in-hospital outcome after acute myocardial infarction.

AIMS: To determine the effect of sex on reperfusion therapy and early mortality after acute myocardial infarction. METHODS: We analysed the characteristics, the reperfusion interventions, and in-hospital mortality in 400 consecutive patients (320 men and 80 women) admitted during the first 6 h of acute myocardial infarction and treated by primary angioplasty, or intravenous thrombolysis with rescue angioplasty. RESULTS: The differences between men and women were age (57 vs 67 years, P = 0.001), systemic hypertension (33 vs 50%, P = 0.02), cigarette smoking (79 vs 30%, P = 0.0001) and contraindications to thrombolysis (28.5 vs 42.5%, P = 0.02). Successful reperfusion of the infarct-related artery was achieved in 84% of patients of both sexes. In-hospital mortality was 7.2% in men and 18.7% in women (P = 0.001). Multivariate analysis was performed by linear logistic regression in order to compare several embedded models, using repeated maximum likelihood ratio tests. The best model involved the variables of cardiogenic shock and age. Addition of the variable 'sex' did not improve the predictive power of this model (P > 0.5). CONCLUSION: During acute myocardial infarction, similar successful early reperfusion rates can be achieved in men and women, despite the lower eligibility of women for thrombolytic therapy. Although in-hospital mortality was higher in women than men, the best predictive model of mortality was the combination of age and cardiogenic shock. Therefore, sex does not appear to be an independent predictor of mortality.

Aged↗
PubMed1997

A randomized trial of a fixed high dose vs a weight-adjusted low dose of intravenous heparin during coronary angioplasty.

AIMS: Prospectively to compare success rate and complications in percutaneous transluminal coronary angioplasty using two doses of heparin. METHODS AND RESULTS: Four hundred patients undergoing coronary angioplasty were randomly assigned to receive 15,000 IU (group A) or 100 IU.kg-1 (group B) of heparin. The angioplasty success rate was 95% of both groups. Stents were placed in 28.5% and 26.5% of patients in groups A and B, respectively (P = 0.73). The primary endopoint (freedom from death, myocardial infarction, unplanned revascularization or bailout stenting) occurred in 91% vs 95% of patients in groups A and B, respectively (odds ratio: 1.88, 95% CI: 0.80-4.50, P = 0.12). Haemoglobin loss was 0.36 +/- 1 and 0.27 +/- 0.9 g.dl-1 in groups A and B, respectively (P = 0.37). The time to sheath removal (735 +/- 265 vs 558 +/- 246 min) and the time to transfer to a stepdown unit (12.7 +/- 4.5 vs 9.8 +/- 4.2 h) were longer in groups A (P = 0.0001 for both comparisons). CONCLUSION: A weight-adjusted low dose of intravenous heparin is at least as safe as a fixed high dose for coronary angioplasty. It allows earlier sheath removal and discharge to a stepdown unit.

Adult↗
PubMed1997

[Orientated management towards reperfusion in the acute phase of myocardial infarction. Results in a cohort of 700 consecutive patients].

The principal objective of treatment of the acute phase of myocardial infarction is the obtention of TIMI 3 complete patency. Usually, only a minority of patients receives thrombolytic therapy and complete reperfusion in unusual. Between June 1988 and April 1996, 700 consecutive patients were admitted to Bichat hospital within 6 hours of the onset of transmural myocardial infarction (81% men; age 59 +/- 13 years). The objective of treatment was to obtain maximal coronary patency in the acute phase, either by thrombolysis (with systematic angiography at 90 minutes and salvage angioplasty in case of failure), or primary angioplasty or conventional treatment (usually in cases of spontaneous reperfusion). The emergency angiography and angioplasty procedures were performed by a medical team on 24 hour duty. During the acute phase, 316 patients received intravenous thrombolysis (angiography at 90' in 302 patients with salvage angioplasty in 79 patients), 304 underwent primary angioplasty (TIMI 3 artery in 85% of cases) and 80 underwent conventional treatment (including 52 cases of angiographically documented spontaneous reperfusion). Therefore, a 81% (566/700) rate of patent TIMI 3 arteries was obtained. The hospital mortality was 8.9%, lower in TIMI 3 arterial patency (6%) than TIMI 2 (20%) or TIMI 0-1 (23%), p < 0.001. The mortality was 4% in patients treated by thrombolysis. Therefore, a reperfusion strategy associating thrombolysis and/or angioplasty provides a high TIMI 3 patency rate in the acute phase of myocardial infarction with a low mortality (6%) in consecutive, unselected patients.

Aged↗
PubMed1997

[Evaluation of the cost of a systematic early reperfusion of the infarction artery by primary or salvage angioplasty].

In order to evaluate the cost of a strategy designed to ensure a maximal early patency rate of the coronary artery responsible for acute myocardial infarction, we retrospectively studied 112 unselected, consecutive patients, treated during the 6 hours following onset of symptoms, either by intravenous thrombolysis (group 1, n = 57) followed by coronary angiography at the 90 th minute, and if necessary rescue angioplasty, or by primary angioplasty (group 2, n = 49), or finally by simple conventional medical treatment (group 3, contraindications to thrombolysis and catheterization, n = 6). The costs of medical treatment were expressed as standard mean costs, and were compared with total hospital expenditure. The overall hospital mortality was 8.0%: 3.5% in group 1, 8.2% in group 2, and 50% in group 3. The total cost of medical procedures during the initial hospital stay was 16,684 F, identical in groups 1 and 2 (17,985 F and 16,780 F, respectively). Total hospital expenditure was 36,254 F, with no significant difference between groups 1 and 2 (34,086 F and 41,670 F, respectively), despite a tendency towards a higher cost in group 2. This tendency reflected that of a longer hospital stay for patients in group 2, due to their more severe condition, but the proportion of medical cost within the total hospital expenditure was lower than in group 1 (40% and 53%, respectively). After one year of follow-up, only one other death from a cardiac cause was reported: the supplementary expenditure amounted to 14,617 F. This maximal reperfusion strategy during the acute phase of myocardial infarction achieved a low hospital mortality and one-year mortality, without a marked excess medical cost compared to previously published estimations. Primary angioplasty appears to have allowed a certain reduction of this cost compared to thrombolysis, but the heterogeneity of the study population does not allow direct comparison of the costs of the 2 reperfusion methods. One half of the total expenditure remains directly dependent on the duration of the hospital stay.

Angioplasty, Balloon, Coronary↗
PubMed1997

[Prognostic significance of early raised cardiac troponine I in unstable angina. Contribution to the identification of a high-risk sub-group].

The authors compared the clinical and angiographic characteristics of 44 patients with unstable angina according to cardiac Troponine I concentrations (TnIc) during early blood sampling and then tried to determine a threshold value to predic the occurrence of cardiac events during the hospital period and after 12 months. Tnlc, creatinine-kinase (CK), CK-MB activity and CK-MB mass were sampled over 48 hours. Forty-five per cent of patients had TnIc > or = 0.1 microgram/L; CK-MB activity and CK-MB mass were detected in 16 and 32% of patients. Age, gender, classification and recurrence of angina, previous cardiac history, risk factors, coronary angiographic appearances were comparable in patients with and without raised TnIc. No major cardiac events occurred during the hospital period in either group. The number of angioplasties and coronary bypass procedures was also comparable. At one year, the incidence of myocardial infarction (N = 4) and death (N = 5) was significantly different in patients with raised Tnlc (33% versus 0% in patients without increased TnIc). However, betablocker therapy was less prescribed in the group with the poorest outcomes and left ventricular dysfunction was also significantly more common in this group. Early elevation of Tnlc could contribute to the identification of a high risk subgroup of patients with unstable angina.

Aged↗
PubMed1995

[Is coronary angioplasty the best treatment of acute myocardial infarction?].

Although the efficacy and simplicity of intravenous thrombolysis makes it the gold-standard for the treatment of acute myocardial infarction, coronary angioplasty remains a valuable alternative. Thrombolysis has the disadvantage of increasing the risk of haemorrhage and is contraindicated in many cases. In addition, thrombolysis appears to have little effect on prognosis in patients with an infarction complicated by cardiogenic shock or those with an occlusion of the venous graft. Finally, when the electrocardiographic findings are not patent, the benefit/risk ratio may be uncertain. Many patients with an acute myocardial infarction are thus totally excluded from thrombolysis making this required selection the main limitation of the treatment. In all these situations, the only effective treatment is primary or direct coronary angioplasty. Major series of patients treated with primary angioplasty have shown that the treatment can be effective on coronary permeability, preservation of ventricular function and short and long-term survival. Several other comparative and randomized studies have confirmed that coronary angioplasty can be an effective alternative, in particular in high-risk patients (elderly subjects, anterior infarctions, women). Finally, the economic data available tend to show that costs for angioplasty are lower than the costs of thrombolysis due to the reduction of hospitalization time and number of readmissions. In conclusion, coronary angioplasty is certainly the best treatment for acute myocardial infarction, at least for the most severe cases and often the only possible option for those with a contraindication for thrombolysis. Operational requirements mean that cardiology emergency facilities will have to be adapted to provide coronary angioplasty 24 hours a day in experienced interventional centres. At the present time, well-managed pre-hospital screening to identify patients with an indication for coronary angioplasty should allow emergency transportation to currently operating centres.

Age Factors↗
PubMed1995

Comparison using dynamic vectorcardiography and MIBI SPECT of ST-segment changes and myocardial MIBI uptake during percutaneous transluminal coronary angioplasty of the left anterior descending coronary artery.

The quantitative relation between ST-segment changes and the severity and extent of myocardial ischemia during coronary occlusion remains unclear. This study assesses whether ST-segment changes during percutaneous transluminal coronary angioplasty (PTCA) correlate with the amount of myocardium at risk, measured with technetium-99m hexakis 2-methoxyisobutyl isonitrile (MIBI; also called sestamibi) single-photon emission computed tomography (SPECT). Quantitative continuous dynamic vectorcardiography was performed during PTCA of the left anterior descending coronary artery in 11 patients (mean age 64.3 years) without previous myocardial infarction. Change in the magnitude of the ST vector (STc-VM) was continuously recorded. A standardized protocol of balloon inflations was used and technetium-99m MIBI was injected intravenously at the onset of the third inflation. SPECT imaging was performed 60 minutes later and compared to a rest acquisition. SPECT was quantified by bull's-eye analysis using: (1) the change in the pathologic/normal area count ratio (delta P/N) as an index of the severity of ischemia; and (2) planimetered defect size during PTCA as an indicator of the size of the area at risk. The delta P/N from baseline to balloon occlusion (22 +/- 11%) was correlated, albeit loosely, to the maximum value of STc-VM (245 +/- 186 microV, r = 0.62, p < 0.05), but there was no correlation between the size of the scintigraphic defect and STc-VM. Likewise, the sum of ST-segment elevation was correlated to delta P/N (r = 0.72, p < 0.02), but not to the size of the scintigraphic defect.(ABSTRACT TRUNCATED AT 250 WORDS)

Aged↗
PubMed1995

Vectorcardiographic monitoring to assess early vessel patency after reperfusion therapy for acute myocardial infarction.

Reperfusion therapy has lowered mortality in patients suffering from acute myocardial infarction. Failure to reperfuse is associated with an increased short- and long-term mortality. In a prospective study we used dynamic vectorcardiography to monitor 96 patients with acute myocardial infarction treated with reperfusion therapy to non-invasively assess coronary patency. The results from continuous monitoring were compared to those obtained from angiography. By using trend-analysis of QRS vector difference and ST vector magnitude, we were able to correctly identify 58 of the 70 patients (83%) with a reperfused infarct-related artery, and 19 of the 26 patients (73%) with a persistently occluded artery demonstrated at an early angiogram (diagnostic accuracy 80%). In patients with high-grade collateral flow to the infarct-related area, the results of the vectorcardiographic monitoring and of angiography showed the largest disagreement, whereas the accuracy of vectorcardiographic monitoring was high: 88% among patients without collaterals. The present results suggest that QRS complex and ST segment vectorcardiographic monitoring is a useful tool for assessing early coronary artery patency, and that dynamic vectorcardiography may help in identifying candidates for emergency coronary angiography.

Acute Disease↗
PubMed1995

[Baroreflexes and congestive heart failure].

Abnormal responses are found in the early stages of heart failure with increased sympathetic and decreased parasympathetic activity, causing peripheral arteriolar vasconstriction and tachycardia respectively. The cardiopulmonary baroreflex may be studied by decreasing venous return ("low body negative pressure") and by measuring vascular resistance forearm. The arterial baroreflex may be studied by changing aortic pressures (by intravenous phenylephrine or nitroglycerin). Orthostatism and the tilt test deactivate the cardiopulmonary and arterial baroreflexes simultaneously. These baroreflexes are impaired in patients with heart failure. Their activation does not cause the usual sympatho-inhibition so contributing to increased sympathetic tone. This dysfunction may result from a change at any point on the reflex pathway: the baroreceptors themselves, the afferent, central and efferent pathways. It is selective as during the cold pressor test, the vasoconstrictor response remains intact. One of the possible mechanisms of baroreflex dysfunction in heart failure is loss of sensitivities of the baroreceptors. This may be multifactorial: structural abnormalities, changes in compliance or functional abnormality. Even if the loss of sensitivity is partially related to a change in compliance, other factors play a role. It is more functional than structural abnormalities because, after cardiac transplantation, the baroreceptors regain their sensitivity within 2 to 3 weeks. Excessive Na-K dependent ATPase activation of the smooth muscle cells of the carotid sinus could lead to hyperpolarization of the cell membrane, so reducing the excitability of the receptor. Aldosterone is one of the factors which could activate the Na-K ATPase, as this hormone directly increases pump activity and favorizes the synthesis of new pumps in the vascular smooth muscle cells.(ABSTRACT TRUNCATED AT 250 WORDS)

Autonomic Nervous System↗
PubMed1995

[Diagnostic value of myocardial thallium stress scintigraphy in the detection of coronary artery disease in patients undergoing chronic hemodialysis].

Atherosclerotic heart disease is the leading cause of death in patients with end stage renal disease, but its non invasive detection remains difficult because of a low efficacy of exercise testing. The aim of the study was to evaluate diagnostic accuracy of thallium myocardial imaging after dipyridamole combined with exercise. Forty two chronic dialysis patients (34 men, 8 women) aged 55 +/- 11 years (range: 36 to 75) without symptom of angina nor myocardial infarction were studied. In each patient, an echocardiography, a myocardial scintigraphy with dipyridamole combined with symptom-limited exercise, and coronarography were performed. A coronary heart disease was diagnosed by coronarography in 10 patients (4.5 and 1 respectively with 1, 2 and 3 vessels diseased). Echocardiography detected a left ventricular hypertrophy (LVH) in 26 patients and a regional asynergia in 14 patients. A positive scintigraphy was present in 11 patients. Three false-positive and 2 false-negative on scintigraphy were noted. Sensibility, specificity, positive predictive value and negative predictive value were respectively evaluated at 80, 73, 73 and 93%. All the five patients with either false-positive or false-negative scintigraphy exhibited a LVH. CONCLUSION. In chronic dialysis patients, coronary heart disease may be detected by thallium myocardial imaging after dipyridamole combined with exercise.

Adult↗