Determination of HbA1c concentrations in patients with acute myocardial infarction: comparison of the DCA 2000 device with the HPLC method.

BACKGROUND: Recent studies suggest that HbA1c is an important predictor of the glycometabolic state of patients admitted for acute myocardial infarction (AMI). OBJECTIVE: We aimed at comparing the results of HbA1c concentrations obtained by 2 different methods in patients with AMI. RESEARCH DESIGN AND METHODS: In a first study, HbA1c was measured in all patients consecutively hospitalized for AMI, during a 6 month period using the HPLC method and the DCA 2000 device in the biochemistry laboratory. In a second study, HbA1c measured by the DCA 2000 device in the intensive care unit was compared with HbA1c determined by HPLC in the biochemistry laboratory in a similar sample of patients. In patients without personal history of diabetes, those patients with HbA1c > 6.5% (HPLC method), were classified as possible diabetes. RESULTS: A total of 146 patients were included (119 males, 27 females; mean age: 63 +/- 15 years). Twenty-seven of the patients had a personal history of diabetes. HbA1c determined by 2 techniques were highly correlated (r = 0.939, P < 0.0001). The mean of the differences (Bland and Altman analysis) was 0.4 +/- 0.3%. Compared with the HPLC method, the sensitivity of DCA 2000 device for the detection of possible diabetes was 81.8 +/- 11.6 and the specificity was 99.1 +/- 0.9%. The diagnostic accuracy of DCA method was 97.5 +/- 1.4%. In the second study, the HbA1c concentrations of 21 additional subjects, determined in an intensive care unit, were not different from the first 21 patients of the first study. CONCLUSIONS: HbA1c can be effectively determined using the DCA 2000 device. This method is reliable and easy to be implemented in an intensive care unit.

Ambulatory monitoring of blood pressure in normal pregnancy.

The definition of hypertensive disorders in pregnancy is plagued by many difficulties, in part related to the limits of intermittent clinic readings of blood pressure. In order to better define the evolution of arterial blood pressure in normal subjects during normal pregnancy, casual and ambulatory (Spacelabs 90207, n = 22 or Diasys 200, n = 26) measurements of blood pressure were performed at gestational months 3, 6, and 9, in 48 normal women aged 18 to 39, both nulliparas (n = 19) and multiparas (n = 29). Ambulatory blood pressure levels were lowest in the first gestational trimester (24-hour mean: 104 +/- 8/63 +/- 6 mm Hg) and rose by a small increment during the last trimester (109 +/- 8/67 +/- 7 mm Hg at 8 months). Mean daytime ambulatory pressure was almost superimposable to clinic measurements at the three time points. A day-night variation in blood pressure level was detectable in all subjects at each recording. It is concluded that during normal pregnancy, ambulatory blood pressure levels were highest in the day and lowest at night at all gestational ages and increased only minimally before the ninth month. Reference values, as defined by the percentile distribution of daytime and nighttime systolic and diastolic blood pressure, may help define more precisely an alteration in the level and/or the circadian variation of arterial blood pressure during abnormal pregnancies.

Resistance to aspirin in vitro at rest and during exercise in patients with angiographically proven coronary artery disease.

BACKGROUND: Acetylsalicylic acid, or aspirin, is widely used in secondary prevention of coronary artery diseases, but the inhibition of platelet aggregation is not uniform in all individuals. OBJECTIVE: To investigate the prevalence of aspirin resistance at rest and during exercise in coronary artery disease patients. MATERIALS AND METHODS: Fifty patients with stable coronary artery disease were prospectively studied. All patients received aspirin (75-300 mg/day for >1 month) and no other antiplatelet therapy. Aspirin resistance was studied, at rest and immediately after a stress test, using the standardized platelet function analyzer (PFA-100(R), Dade-Behring). Aspirin resistance was defined as a normal collagen/epinephrine closure time (<186 s). RESULTS: Ten patients (20%) were aspirin-resistant at rest. Out of the 40 patients who were aspirin-sensitive at rest, 9 (22%) were aspirin-resistant immediately after the exercise stress test. There were no differences in aspirin sensitivity regarding gender, age, diabetes, hypertension, dyslipidemia, platelet count, medical treatment or number of the coronary arteries involved. CONCLUSIONS: Aspirin resistance is detected, at rest, in 20% of our patients with stable coronary artery disease. Aspirin treatment does not seem to protect against exercise-induced platelet activation in 22% of such patients, despite aspirin sensitivity at rest.

Perforated aneurysm of the anterior mitral leaflet: late assessment with transesophageal echocardiography.

We present a case study of a 54-year-old patient with a perforated aneurysm of the anterior mitral valve leaflet, diagnosed 13 years after an episode of bacterial endocarditis by transesophageal echocardiography. This report illustrates the superiority of transesophageal echocardiography in the diagnosis and management of valvular endocarditis.

Nomogram for Doppler echocardiographic assessment of mitral stenosis in atrial fibrillation.

Non-invasive assessment of the stenotic mitral valve area is often difficult when the mitral stenosis is associated with atrial fibrillation. In this study, 16 patients with mitral stenosis and atrial fibrillation were evaluated by transthoracic Doppler echocardiography. The mitral valve area calculated by the pressure half-time method was 1.65 +/- 0.73 cm2. The enddiastolic mitral gradient was obtained from the enddiastolic forward mitral flow velocity by application of the simplified Bernoulli equation. For each patient there was a linear relationship between the enddiastolic mitral gradient and the corresponding RR interval. The slope and intercept of this relationship were significantly correlated with the mitral valve area. From the regression equations describing these correlations we established a nomogram ascertaining mitral valve area from enddiastolic mitral gradient and corresponding heart rate. This nomogram was helpful in the non-invasive assessment of stenotic mitral valve area in the presence of atrial fibrillation.

Lipomatous hypertrophy of the cardiac interatrial septum: an unusual complication in long-term home parenteral nutrition in adult patients.

The aim of this study was to report unusual echocardiographic findings in patients on long-term home parenteral nutrition suggesting lipomatous hypertrophy of the cardiac interatrial septum. Seven patients (two women and five men, mean age 58 years) were prospectively evaluated by two-dimensional echocardiography before and during home parenteral nutrition for severe short-bowel syndrome. Parenteral caloric intake was 33 +/- 4 kcal/kg per day (mean +/- SD), with a mean supply of lipid emulsion of 1 g/kg per day. The first echocardiography, performed before initiation of home parenteral nutrition, was normal in the seven patients. The second echocardiography, performed 5 to 43 months (mean 20 months) later, revealed a significant increase of the thickness of the atrial septum in all patients (+8.3 +/- 3.6 mm; p less than 0.01), consistent with the diagnosis of lipomatous hypertrophy in four patients, and moderate fat accumulation in two others. The septum thickness measured after the nutritional support period was significantly correlated (p less than 0.05) with the total amount of nutrient and lipid infused. Cardiac nuclear magnetic resonance imaging was performed in two patients; it suggested the adipose nature of interatrial septum deposit. None of the patients developed clinical or electrocardiographic symptoms during the period of nutrition. We suggest that patients undergoing long-term home parenteral nutrition be screened for this new and unusual cardiac abnormality. Whether the latter might have clinical consequences in these patients remains to be determined.

[Doppler parameters in the followup of and evaluation of patients with heart failure]. / Paramètres doppler dans le suivi et l'évaluation des patients insuffisants cardiaques.

Cardiac failure plays an increasing role in the daily practice of cardiologists and internists. Cardiac failure is purely diastolic in nearly 40% of cases. Whether purely diastolic or mixed, cardiac failure requires appropriate management in the long term. A step by step approach is often necessary and echocardiography with Doppler analysis of blood flow is certainly one of the most pertinent methods of following up these patients. In addition, new technologies now provide access to quantifiable regional left ventricular systolic and diastolic function: Doppler tissue and strain rate imaging will certainly be an additional help for the adaptation of strategies of management of cardiac failure in the near future.

[Contribution of doppler echocardiography in the evaluation of ventricular filling in cardiac insufficiency and estimation of filling pressures]. / Apports de l'échocardiographie doppler dans l'évaluation du remplissage ventriculaire de l'insuffisant cardiaque et l'estimation des pressions de remplissage.

The study of diastolic function is an essential step in Doppler echocardiographic investigation of cardiac failure. Although the recording of transmitral flow remains the basis of analysis of diastolic function, it should be completed by other Doppler parameters. In fact, the simple analysis of transmitral flow is not sufficient because of the interplay of other factors, especially the preload. The authors describe the complementary ultrasonographic approaches for analysis of diastolic function, especially the ventricular filling pressures, by recording of pulmonary venous flow, the kinetics of the mitral annulus and the propagation of intra-ventricular flow.

[Physiopathology of myocardial infarction: the acute coronary occlusion]. / Physiopathologie de l'infarctus du myocarde: l'occlusion coronaire aiguë.

Rupture of the atheromatous plaque, thrombosis and local vasoconstriction are involved in the genesis of acute myocardial infarction. The vulnerability of the plaque depends on its histological structure. Its fragility is related to the size of the lipid core, the thinness of the fibrous capsule and the inflammatory reaction. External aggression favourites rupture. This triggers both thrombogenesis by bringing the blood cells into contact with thrombogenic subendothelial factors and local vasoconstriction due to endothelial dysfunction. Although rupture of the plaque is an unpredictable event, there is a circadian variability the highest incidence of infarction being between 6 a.m. and midday. Comprehension of the physiopathology of myocardial infarction has opened up new therapeutic approaches which should reduce the incidence of plaque rupture. Prevention is based on stabilisation of the plaque by dietary hygiene, lipid-lowering drugs and, maybe, in the future, by local application of antisense oligonucleotides. Finally, anti-aggregant therapy (aspirin or anti-GIIb-IIIa) could prevent the formation or extension of the thrombus.

[Tissue characterization by study of myocardial response to ultrasound. Review of the literature and perspectives]. / Caractérisation tissulaire par étude de réponse du myocarde aux ultrasons. Revue de la littérature et perspectives.

Echocardiography is a routine daily cardiological investigation. Recent technological developments suggest that it may become possible to quantify myocardial texture and thereby achieve histological and functional definitions of cardiac diseases. Two approaches are under evaluation: "videodensitometry" uses tools of statistical quantification from the echocardiographic image; more recently, analysis of the radiofrequency signal has been proposed. This is based on direct exploitation of a continuous signal at the transducer head of wide dynamic range containing all the information received by the piezo-electric crystals. These two approaches have given encouraging preliminary results in the recognition of different myocardial hypertrophic reactions, in diabetic cardiac disease and in the identification of myocardial viability. Despite the many remaining problems, the perspectives are promising and a new field of echocardiography should see the light of day.

[Myocardial infarction by complete thrombosis of the left main coronary artery: emergency treatment with angioplasty with implantation of a coronary stent and follow-up at one year: a case report]. / Infarctus par thrombose complète du tronc commun coronaire gauche: traitement en urgence par angioplastie avec pose de prothèse endocoronaire et suivi à 1 an. A propos d'un cas.

Acute occlusion of the left main coronary artery is usually responsible for cardiogenic shock, severe arrhythmias or sudden death. Despite the widespread use of emergency coronary angiography in acute myocardial infarction, occlusion of the left main coronary artery is rarely observed and its treatment remains controversial. The authors report the case of a young man with a previous history of radiotherapy for Hodgkin's disease, admitted for acute myocardial infarction due to complete thrombosis of the left main coronary artery treated as an emergency by percutaneous transluminal angioplasty and implantation of a Palmaz Schatz stent. There were no complications of the procedure and the patient was asymptomatic one year later.

[Ultrasonic myocardial characterization. Application of an original method of acoustic quantification to analysis of healthy and hypertrophic interventricular septal myocardium]. / Caractérisation myocardique en échographie. Application d'une méthode originale de quantification acoustique à l'analyse du septum interventriculaire de myocardes sains ou hypertrophiques.

Echocardiography does not provide objective tissue characterisation of sonified tissues. A recent advance has been the introduction of the radiofrequency signal. At present, its exploitation remains a research tool. The required material for quantification is still insufficiently robust and discriminative. The indices derived from histograms of grey scales are calculated by the majority of workers for regions of interest manually positioned in the image. This statistical method allows analysis of the average grey level but not of the architecture of the tissue examined. Tissue characterisation is, therefore, only a potential feature of echocardiography. The authors' approach consists in developing software applied to digital signal provided by the echograph and not directly by the transducer, as in the research based on the use of radiofrequency signals. This software allows characterisation of the texture by two statistical methods applied to signal processing: the histograms of the grey scales, the matrix of co-occurrence (assessing the make-up of the different grey scales in the region of interest). This tool of tissue characterisation is presented here in the studies of the interventricular septum in the parasternal long axis view. Two populations, one with healthy myocardium and the other with myocardial hypertrophy, have been studied. These two populations are differentiated in a significant manner by their respective values of parameters of myocardial texture characterisation in early diastole. Despite a number of methodological problems, this study confirms the hopes that it will be possible in the near future to obtain a quantitative "histological" definition of tissues by echocardiography.

[Normal coronary angiography. Survival and functional status at 6 years]. / Coronarographie normale. Pronostic vital et fonctionnel à 6 ans.

Despite the development of non-invasive diagnostic techniques, the absence of significant coronary stenosis is observed in 10 to 30% of coronary angiographic studies. The authors report the survival and functional status at 6 years of 172 consecutive patients with symptoms of angina without significant angiographic coronary stenosis. The average age was 60.8 years with a sex ratio of 1.1 and chest pain as the indication for coronary angiography in over 90% of cases. The global mortality after an average of 75.6 months follow-up was 11%, lower in women (8.5%) than in men (13.3%) with an annual mortality of 16.3 per thousand. Sudden death was observed in 4 patients and a third of deaths was of cardiac origin. The persistence of symptoms was reported by 58% of patients, mainly atypical chest pain. Despite the result of coronary angiography, nearly half of the patients were followed up annually by a cardiologist, two thirds remained on anti-anginal therapy, 20% were treated by psychotropic agents and hospital admission to the cardiology department was required in 22% of cases during follow-up. None of the patients had myocardial infarction. Survival and myocardial function after normal coronary angiography therefore appear to be good in contrast with the functional status of these patients.

[Platelet polymorphism and coronary artery disease]. / Polymorphisme plaquettaire et coronaropathies.

Several publications over the last ten years have addressed the problem of genetic mutation coding platelet membrane glycoproteins and thrombotic arterial disease. The principal polymorphisms studied are those of glycoproteins GPIIIa, GPIb and the GPIa-IIa complex. The relationships of each of these polymorphisms and myocardial infarction or coronary artery disease are reported and are often subject to controversy. The polymorphism PLA2 of the GPIIIa has been shown to be a risk factor for infarction in young people, especially when associated with cigarette smoking. Its role in triggering myocardial infarction or in the severity of coronary artery disease is not so clear in the general population. Two types of polymorphism concerning the GPIb and that of the GPIa-IIa complex should also predispose to early coronary thrombotic complications. In addition, the study of these platelet polymorphisms gives a better insight into individual sensitivity to platelet antiaggregant therapy.

[Doppler echographic evaluation of mitral valve stenosis with atrial fibrillation. Construction of a nomogram]. / Evaluation par échocardiographie Doppler des sténoses mitrales en fibrillation auriculaire. Construction d'un nomogramme.

Doppler echocardiographic evaluation of mitral stenosis is often difficult in patients with atrial fibrillation. Sixteen patients were examined by transthoracic Doppler echocardiography and the relation between the variations in transmitral end diastolic pressure gradient and the length of the corresponding cardiac cycles was analysed. Mitral valve surface area (1.65 +/- 0.73 cm2) was determined by the pressure half-time method. The end diastolic transmitral pressure gradient was calculated from the simplified Bernouilli formula applied to end diastolic mitral flow velocity. In each patient, a linear relationship was observed between the end diastolic mitral gradient and the corresponding RR interval. The slope and intercept of the graph correlated significantly to mitral valve surface area (r = 0.72, p < 0.002 and r = 0.93, p < 0.00001, respectively). Using regression equations describing these correlations, it has been possible to construct a nomogramme indicating mitral valve surface area as a function of mitral end diastolic pressure gradient and the duration of the corresponding RR cycle. This nomogramme facilitates Doppler evaluation of mitral stenosis in atrial fibrillation.

[Value of echocardiography in the diagnosis of a complicated form of Kawasaki's disease]. / Intérêt de l'échocardiographie dans le diagnostic des formes compliquées de la maladie de Kawasaki.

Kawasaki disease affects children under 4 years of age and is characterized by fever, mucocutaneous rash and cervical lymph node enlargement. It is often complicated by coronary vasculitis and/or pericarditis, myocarditis and endocarditis. Echocardiography is indispensable to diagnose and follow up these complications. A study of the literature and of 4 personal patients showed that it is also useful for the early detection of coronary aneurysm and simple dilatation of the coronary arteries. The sensitivity and specificity of echocardiography in recognizing these complications are such that coronary angiography is exceptionally required. In the search for a cause of prolonged fever in children, the sensitivity of echocardiography makes it possible to diagnose an atypical form of Kawasaki disease.

[Spontaneous course of myxoma of the left atrium]. / Evolution spontanée du myxome de l'oreillette gauche.

Little is known about the natural history of left intra-atrial myxomas. We report 3 cases of that disease where successive echocardiographic examinations provided figures of 11, 12 and 14 months respectively for the formation of the tumour in the left atrium. Echocardiography is perfectly reliable for the diagnosis of myxoma. False-negative results are rare and usually due to very small myxomas being beyond the resolution potential of the instrument; this seems to have been the case in 2 of our 3 patients. Two data, however, remain unknown: the beginning of formation and the rapidity of tumoral growth. These 3 cases raise the problem of repeat echocardiography some time after a cerebral accident of suspected embolic origin, when the initial examination is negative.

[Development at 5 years of chronic branchial blocks in 164 patients fitted with pacemakers without documented spontaneous atrioventricular block. Study of predictive criteria]. / Evolution à 5 ans des blocs de branches chroniques chez 164 patients appareillés par stimulateur sans bloc auriculo-ventriculaire spontané documenté. Etude des critères prédictifs.

When no complete atrioventricular block (CAVB), paroxysmal and spontaneous, is recorded, implanting a pacemaker in patients with chronic bundle branch block (CBB) has an arbitrary aspect which must be reduced as much as possible. In order to determine more precisely the criteria predicting an evolution towards CAVB, we studied the electrocardiographic changes observed in 164 patients with various types of CBB. 110 patients had a right bundle branch block which was isolated (RBB) in 16 cases, associated with a left anterior hemiblock (RBB + LAH) in 74 cases and associated with a left posterior hemiblock (RBB + LPH) in 20 cases; 54 patients had a left bundle branch block with a normal axis in 26 cases (LBB - NA) and with a strongly left axis in 28 cases (LBB - LA). All patients had been fitted with a pacemaker. Patients were followed up for a mean period of 5 years (59.1 +/- 25.3 months), the minimum being 2 years. 49.4 p. 100 of them had experienced one ore serveral syncopes. The basal HV interval, studied in 90.2 p. 100 of the patients, was 60 ms or more in 64.9 p. 100 of those who were explored. An ajmaline test, performed in 60 of the 85 patients whose basal HV was less than 70 ms, demonstrated at least a 100 ms or more prolongation of HV in 41 cases (68.3 p. 100).(ABSTRACT TRUNCATED AT 250 WORDS)

[Reproducibility of measurements of blood gas exchange during exercise in mild cardiac failure: need for a preliminary test?]. / Reproductibilité de la mesure des échanges gazeux a l'effort chez l'insuffisant cardiaque modéré: nécessité d'une épreuve préliminaire?

The reproducibility of blood gas exchange measurements on exercise in chronic cardiac failure has already been established in patients familiar with this technique. The aim of this prospective study was to evaluate the reproducibility of cardiopulmonary parameters on exercise in a population of patients who had never undergone this type of investigation. Twenty patients with chronic cardiac failure in classes I to III of the NYHA classification, with a mean age of 55 +/- 11.5 years and a mean LV ejection fraction of 31.2 +/- 9%, underwent two cardiopulmonary exercise tests (CPX Medgraphic) performed on a bicycle ergometer. Patients underwent maximal exercise stress testing attaining 89% of the theoretical maximal heart rate and 1.14 of the respiratory quotient during the first test. There was no significant change in peak VO2 (22.5 ml/min/kg vs 22.6 ml/min/kg) or in ventilatory anaerobic threshold (12.8 ml/min/kg vs 12.7 ml/min/kg) between the two tests. The ventilatory anaerobic threshold could not be measured in one patient and seemed less reproducible than peak VO2 with a standard deviation of relative differences (T2-T1/T1) of 10.4 versus 7.8%. There was a significant increase in the duration of exercise (7.4 +/- 9.2%; p < 0.002) and a ventilatory flow (4.5 +/-, p = 0.03). This study shows that peak VO2 is a reproducible measurement in mild to moderate chronic cardiac failure, even in the absence of a preliminary test to familiarize the patient with the equipment. The reproducibility of the ventricular anaerobic threshold is less satisfactory than that of peak VO2. The increase in the duration of exercise is more dependent on motivation and should not be taken into account alone in the functional evaluation of chronic cardiac failure.

[The echocardiographic examination in adult cardiomyopathy]. / L'examen échocardiographique des cardiomyopathies de l'adulte.

Echocardiography allows distinction between the diastolic dysfunction of hypertrophic or restrictive cardiomyopathies and the systolic dysfunction of dilated cardiomyopathy. The diagnosis and prognosis may be deduced from echocardiographic parameters. In hypertrophic cardiomyopathy systolic function is normal and there is asymmetric left ventricular hypertrophy (> 13 mm) associated with a reduced diastolic dimension and atrial dilatation resulting from diastolic dysfunction. The prognosis could be related to the severity of left ventricular hypertrophy; right ventricular hypertrophy is uncommon and its severity seems to be related to that of left ventricular hypertrophy. Restrictive cardiomyopathies are less common and amyloidosis is the commonest cause. Symmetric hypertrophy with reduced diastolic dimensions is observed; right ventricular involvement occurs in about 30% of cases. The prognosis seems to be related to the degree of parietal infiltration and, at advanced stages, systolic function is abnormal (fractional shortening < 20% with a left ventricular diastolic dimension > or = 55 mm) and rapidly fatal. Dilated cardiomyopathy is diagnosed when wall thickness is normal but left ventricular diastolic dimensions > 27 mm/m2 and ejection fraction < 45%. Right and left ventricular dimensions of the same size, left ventricular diastolic dimensions > 70 mm and left ventricular ejection fractions < 20% are poor prognostic indicators.