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E Delacrétaz

Publications and source records attributed to E Delacrétaz.

At least 19 recordsLinked to original sources
PubMed2002

[Radiofrequency catheter ablation of ventricular tachycardias].

Management of patients with ventricular tachycardia (VT) is often difficult. Drug therapy is often ineffective. Implantable cardioverter defibrillators (ICDs) can terminate VT episodes but do not prevent them. Radiofrequency (RF) catheter ablation can suppress arrhythmias in selected patients. However, the procedure is often challenging and success rates lower than for ablation of supraventricular tachycardias. The mapping and ablation approach depends on the VT mechanism. Monomorphic VT in patients without structural heart disease is referred to as idiopathic and has a focal origin. These VTs can be abolished by ablation in most of the patients. In VT due to reentry within an area of scar from an old myocardial infarction or cardiomyopathic process, critical parts of the circuit may be difficult to localize, rendering RF ablation challenging. In patients with monomorphic VT, prevention of VT recurrence can be achieved in 55% to 80% of patients. Multiple morphologies of VTs and circuits that are located deep in the endocardium are common problems that reduce efficacy. Furthermore, mapping to identify target regions for ablation can be more difficult if VT is rapid and not tolerated, or not inducible. Recently, multisite mapping of the arrhythmia substrate during sinus rhythm or multisite activation mapping of a few VT beats were shown to be effective for ablation of these "unmappable VTs". Bundle branch reentry tachycardia occur in patients with nonischemic cardiomyopathies, mostly valvular heart disease and can be successfully abolished with RF ablation of the right bundle. However, some of these patients may develop recurrences due to other types of VT. Recent technical developments have increased efficacy and simplified the approach of RF ablation of VT in patients with structural heart disease. However, long-term efficacy is not accurately predictable and implantation of an ICD is mandatory in most of the patients with severely depressed left ventricular function.

Cardiomyopathy, Dilated↗
PubMed2002

Wide complex tachycardia and congenital heart disease.

We present a patient with congenital heart disease and haemodynamically poorly tolerated wide QRS tachycardia. Differential diagnosis and therapy are discussed. After the patient underwent heart transplantation, and the substrates for ECG abnormalities and arrhythmias were demonstrated in the explanted heart.

Adult↗
PubMed2001

Diastolic dysfunction precedes myocardial hypertrophy in the development of hypertension.

BACKGROUND: Left ventricular (LV) hypertrophy and impaired diastolic function may occur early in systemic hypertension, but longitudinal studies are missing. METHODS: We performed an echocardiographic follow-up study in young initially normotensive male offspring of hypertensive (OHyp) (n = 25) and normotensive (ONorm) (n = 17) parents. Blood pressure (BP), LV mass, and mitral inflow were determined at baseline and after 5 years. Pulmonary vein flow pattern assessment and septal myocardial Doppler imaging were additionally performed at follow-up. RESULTS: At follow-up, BP was not significantly different between the two groups (128 +/- 11/84 +/- 10 v 123 +/- 11/81 +/- 5 mm Hg, OHyp v ONorm) but five OHyp had developed mild hypertension. LV mass index remained unchanged and was not different between the two groups at follow-up (92 +/- 17 v 92 +/- 14 g/m2). Diastolic echocardiographic properties were similar at baseline, but, at follow-up, the following differences were found: mitral E deceleration time (209 +/- 32 v 185 +/- 36 msec, P < .05) and pulmonary vein reverse A wave duration (121 +/- 15 v 107 +/- 12 msec, P < .05) were prolonged in the OHyp as compared to the ONorm. Compared to the normotensive subjects, the five OHyp who developed hypertension had more pronounced alterations of LV diastolic function, that is, significantly higher mitral A (54 +/- 7 v 44 +/- 9 cm/sec, hypertensives v normotensives, P < .05), lower E/A ratio (1.31 +/- 0.14 v 1.82 +/- 0.48, P < .05), increased systolic-to-diastolic pulmonary vein flow ratio (1.11 +/- 0.3 v 0.81 +/- 0.16, P < .005), longer myocardial isovolumic relaxation time (57 +/- 7 v 46 +/- 12 msec, P < .05) as well as smaller myocardial E (10 +/- 1 v 13 +/- 2 cm/sec, P < .05) and E/A ratio (1.29 +/- 0.25 v 1.78 +/- 0.43, P < .05), despite similar LV mass (91 +/- 16 v 93 +/- 18 g/m2). CONCLUSIONS: Over a 5-year follow-up, initially lean, normotensive, young men with a moderate genetic risk for hypertension, developed Doppler echocardiographic alterations of LV diastolic function compared to matched offspring of normotensive parents. These alterations were more pronounced in the OHyp who developed mild hypertension and occurred without a distinct rise in LV mass.

Adult↗
PubMed2001

Radial artery compliance in response to mental stress in normotensive offspring of hypertensive parents.

OBJECTIVES: Compared to normal subjects hypertensive patients have an increased radial artery isobaric distensibility, contrasting with a decrease in elasticity of large arteries and systemic compliance. To address the question whether elasticity is increased in response to long-standing elevated blood pressure or is present at an early stage of the disease, we compared normotensive offspring of hypertensive parents with control subjects. Furthermore, enhanced sympathetic response to mental stress was demonstrated in individuals predisposed to hypertension and might contribute to the elevation of blood pressure via a peripheral mechanism. Thus, an abnormal vasoconstrictive response of the radial artery to psychological stress was sought in these subjects. DESIGN: The geometry and the elastic porperties of the radial artery were assessed in normotensive offspring of hypertensive and normotensiven parents at baseline and during mental stress. METHODS: A high-precision echo-tracking ultrasound device was combined with photoplethysmography for continuous measurement of radial artery diameter and isobaric distensibility in 18 normotensive offspring of parents with essential hypertension and 18 control subjects under resting conditions and during a 3-minute mental stress test. RESULTS: Baseline arterial distensibility and compliance were comparable in offspring of hypertensive and normotensive parents. During mental stress, blood pressure and heart rate increased similarly in both groups. Adrenergic activation did not alter the elastic properties of the radial artery in the individuals with a genetic predisposition to essential hypertension. CONCLUSIONS: There was no alteration in elastic properties of the radial artery in normotensiven individuals at genetic risk to develop arterial hypertension. Furthermore, mental stress did not abnormally increase the vascular tone of this medium-sized muscular artery in these subjects as compared to controls. This indicates that functional and/or structural vascular alterations do not precede a distinct rise in blood pressure or abnormal blood pressure reactivity in subjects prone to develop essential hypertension.

Adult↗
PubMed2001

Increased central body fat deposition precedes a significant rise in resting blood pressure in male offspring of essential hypertensive parents: a 5 year follow-up study.

OBJECTIVES: As long as offspring of essential hypertensive parents (OHyp) are lean, their blood pressure usually remains within normal limits. The mechanism(s) transforming this 'genetically dysregulated normotension' into hypertension are unclear. We hypothesized that OHyp are not only genetically prone to develop hypertension, but may also have a particular propensity to accumulate central body fat. DESIGN: A 5-year follow-up cohort study. SETTING: University Hospital in Switzerland. PARTICIPANTS: Seventeen young (25 +/- 1 years, mean +/- SD), lean healthy normotensive male OHyp and 17 age- and sex-matched offspring of normotensive parents (ONorm) paired for baseline blood pressure with the OHyp. MAIN OUTCOME MEASURES: Resting and exercise blood pressure, body weight, body mass index (BMI) and waist-to-hip ratio were assessed at baseline and after 5 years. RESULTS: At baseline, body weight, BMI, waist-to-hip ratio and blood pressure did not differ significantly between OHyp and ONorm. At follow-up, body weight was increased in both groups (from 73.9 +/- 6.0 to 77.7 +/- 8.1 kg in OHyp, P = 0.008, and from 71.5 +/- 6.9 to 73.5 +/- 6.6 kg in ONorm, P = 0.03). BMI followed a similar pattern. In contrast, waist-to-hip ratio increased in OHyp (from 0.84 +/- 0.03 to 0.87 +/- 0.03, P = 0.012), but not in ONorm (from 0.84 +/- 0.03 to 0.84 +/- 0.04, P = 0.79) and was therefore higher in OHyp at follow-up (P = 0.011, OHyp versus ONorm). Peak systolic blood pressure during dynamic exercise also rose at 5 years in the OHyp (from 182 +/- 10 to 214 +/- 17 mmHg, P = 0.0001) while resting systolic blood pressure only tended to do so (from 121 +/- 7 to 128 +/- 12 mmHg, P = 0.07). In ONorm, resting and peak dynamic exercise systolic blood pressure remained unchanged (119 +/- 11 versus 121 +/- 9 mmHg, baseline versus follow-up, P = 0.40, and 186 +/- 12 versus 196 +/- 22 mmHg, P = 0.10, respectively). Thus, systolic peak exercise blood pressure was significantly (P = 0.014) elevated at follow-up in OHyp compared to ONorm, while resting systolic blood pressure only tended (P = 0.06) to do so. CONCLUSIONS: Initially lean normotensive OHyp have a disparate long-term course of central body fat as compared to ONorm. Thus, OHyp are not only genetically prone to develop hypertension, but they also have a particular propensity to accumulate central body fat, even before a distinct rise in resting blood pressure occurs. The exaggerated blood pressure response to exercise observed at follow-up in the OHyp represents another marker that confers them a greater risk of developing future hypertension.

Adipose Tissue↗
PubMed2001

[Implantable defibrillator. Update].

The implantable cardioverter-defibrillator is a device able to detect and efficiently treat life-threatening ventricular arrhythmias. Its decisive accomplishment in reducing sudden cardiac death and total cardiac mortality, opposed to the insufficient reliability of the traditional therapies explains its present ascendancy. In this review, the working principles and the implant techniques are developed, as well as the complications and the usual problems which could be encountered in implanted patients. Finally, the current indications are discussed in the light of recent clinical trials.

Arrhythmias, Cardiac↗
PubMed1999

Coronary and peripheral artery remodeling in patients undergoing PTCA: An intracoronary and transcutaneous ultrasound study.

The aim of this study was to assess the relationship between the plaque burden of nonstenotic coronary artery segments and the wall thickness of peripheral arteries using intracoronary and transcutaneous ultrasound imaging, respectively. Intracoronary ultrasound (CVIS, 3.5 Fr) was performed in 27 patients undergoing percutaneous transluminal coronary angioplasty. Carotid arteries were imaged by B-mode ultrasound with semiautomatic edge detection and radial arteries by high resolution A-mode echotracking (NIUS 2). Quantitative measurements included coronary artery intima-media cross-sectional area (IM(CSA)) and cross-sectional narrowing (CSN), as well as intima-media thickness (IMT) and lumen radius (r) of the common carotid and the radial arteries. Intima-media thickness was increased in coronary, carotid, and radial arteries. Coronary arteries had an IM(CSA) of 7.7 +/- 2.5 mm(2) and a CSN of 24% +/- 8%. Despite this moderate plaque burden, lumen area was preserved (12.3 +/- 4.2 mm(2)) because of compensatory enlargement of coronary arteries. Right and left carotid and right radial arteries had an IMT of 575 +/- 78 microm, 570 +/- 129 microm, and 328 +/- 61 microm, respectively. There was no correlation between coronary IM(CSA) and carotid IMT (r = 0.07) or radial IMT (r = 0.02), and there was no correlation between coronary CSN and carotid IMT/r (r = 0.12), or radial IMT/r (r = 0.25). In conclusion, in these patients with symptomatic ischemic disease no relationship between IMT of the coronary arteries and IMT of carotid or radial arteries was found. Although increasingly popular, IMT of peripheral arteries may be of limited value as surrogate marker for the severity of coronary artery disease. Cathet. Cardiovasc. Intervent. 48:12-17, 1999.

Adult↗
PubMed1998

[Secondary prevention of ischemic heart disease after coronary revascularization].

This study was aimed to assess the compliance with policies for secondary prevention of coronary heart disease (CHD) one year after coronary artery revascularization with special attention to the management of hyperlipidemia. One year after coronary revascularization during the year 1994, patients were contacted by letter to determine the modification of their risk factors, the treatment patterns for hypercholesterolemia and to have their plasma lipid level and blood pressure measured. Of the 245 consecutive patients contacted (110 after coronary artery bypass grafting, and 135 after percutaneous transluminal coronary angioplasty), 186 (76%) provided the information required for further analysis. Excluding the patients older than 65 years, only 29 out of 97 patients (30%) with a total cholesterol of more than 5.2 mmol/l, and only 20 out of 52 patients (38%) with a total cholesterol of more than 6.2 mmol/l were receiving lipid lowering therapy 1 year after coronary artery revascularization. In contrast, 97% (n = 180) of the entire population studied were taking antiplatelet drugs and/or coumadine. Participation in an in-house rehabilitation program yielded a positive influence on smoking, but not on treatment of hypercholesterolemia. In conclusion, only a small proportion of patients with documented CHD and hypercholesterolemia were being treated for their lipid disorder 1 year after coronary artery revascularization. In contrast, the great majority of patients received antiplatelet and/or coumadine therapy: These results indicate that the compliance with published treatment guidelines for hyperlipidemia in patients with CHD is still highly inadequate, irrespective of the participation in a rehabilitation program.

Aged↗
PubMed1998

Use of coronary angioplasty, bypass surgery, and conservative therapy for treatment of coronary artery disease over the past decade.

AIMS: There is a continuous increase in the number of percutaneous transluminal coronary angioplasty procedures performed per year per population in most industrialised countries. This analysis searches for trends in treatment decisions after diagnostic coronary angiography. METHODS AND RESULTS: The degree of coronary artery disease and the therapeutic strategy were determined retrospectively in consecutive patients undergoing coronary angiography at a Swiss university hospital during three different time periods in the past 11 years (n = 750 in 1994, n = 500 in 1990, and n = 545 in 1983). The indication for coronary angioplasty rose from 45% in 1983 to 78% in 1990 and 87% in 1994 in patients with one-vessel disease, from 25% to 38% and 71% in patients with two-vessel disease, and from 10% to 24% and 29% in patients with three-vessel disease. In contrast, the use of conservative therapy declined with time, independent of the severity of coronary artery disease. Indications for coronary artery bypass grafting decreased in patients with two-vessel disease, but did not change in patients with three-vessel disease over the 11 year period. CONCLUSIONS: The use of coronary angioplasty, bypass surgery, and conservative therapy changed drastically over the past decade, with an increasing use of angioplasty and a multivessel disease, and of bypass surgery in two-vessel disease. The expansion of coronary angioplasty is mainly related to increased use in patients previously treated conservatively.

Adult↗
PubMed1997

[Use and significance of intravascular ultrasonic imaging].

Intravascular ultrasound (IVUS) imaging of coronary arteries has recently become possible in vivo with the improvements achieved in the miniaturisation of ultrasound transducers. IVUS provides informations complementary to angiography, and is considered as the gold standard for the assessment of lumen size, plaque thickness and plaque distribution. As formerly demonstrated by pathological studies, IVUS also reveals an underestimation of plaque thickness with angiography and an incomplete assessment of the true morphologic distribution of the plaque burden. Among its clinical applications, IVUS can be used to monitor revascularisation procedures, and may provide very accurate measurements of progression or regression of coronary atherosclerosis and of the extent of posttransplant vasculopathy. IVUS was employed successfully to assess and optimize the results of percutaneous transluminal coronary angioplasty. Clinical studies have shown that the risk of restenosis is inversely proportional to the size of the postprocedural lumen. With the guidance of percutaneous transluminal angioplasty by IVUS, balloon size and inflation pressures were increased, and better results were obtained with larger lumen size in comparison to the results of the procedures assessed by angiography alone. These improvements contributed to abandon the anticoagulation after stent implantation in most cases. In spite of the valuable information provided by IVUS, its role in clinical settings should still be defined IVUS prolongs the revascularisation procedure and enhances its costs and risks. Thus, the cost effectiveness of IVUS in its clinical application should be determined by prospective studies.

Angioplasty, Balloon, Coronary↗
PubMed1997

Therapeutic strategy with total coronary artery occlusions.

Patients with a coronary artery occlusion are more likely to be revascularized surgically or to be treated conservatively than patients without occlusion. A higher prevalence of patients with multivessel coronary artery disease (CAD), particularly with 3-vessel CAD, in the group with occlusion may account in part for this difference in management.

Angioplasty, Balloon, Coronary↗
PubMed1997

Relationship between the prescriber's instructions and compliance with antibiotherapy in outpatients treated for an acute infectious disease.

Antibiotics are frequently prescribed in everyday practice for the management of acute microbial infections. The present study was designed to assess the relationship between the prescriber's instructions and the patient's adherence to a prescribed schedule of twice-daily doses of antibiotic for at least 5 days to treat an infectious disease. The trial was conducted by ten practicing physicians on ambulatory patients. Compliance with the antibiotic regimen was evaluated using a microelectronic device, the Medication Event Monitoring System (MEMS). Seventy patients were prescribed an antibiotic in twice-daily doses for 5 to 14 days (mean = 8). Data were available for analysis from 68 of them, aged 18 to 84 years (mean = 44). The "taking compliance" for the whole story group, which corresponded to the ratio of the number of times the bottle was opened and the total number of doses prescribed during the monitoring period, was nearly perfect at 99.6%. However, only 32.6% of the medications was taken within 1 hour before or after the 12-hour interval expected to be optimal for a twice-daily regimen. It therefore seems highly desirable that physicians give more detailed recommendations to their patients regarding the drug regimens they prescribe.

Adolescent↗
PubMed1996

Low-dose thrombolysis for thrombosed prosthetic heart valve.

This report describes two cases of successful fibrinolysis of thrombosed tricuspid and mitral valve prostheses (Carbomedics; Austin, Texas) with low-dose urokinase therapy corresponding to only one third of the dose usually recommended.

Heart Valve Prosthesis↗
PubMed1995

[Noninvasive assessment of morphology and function of the great vessels].

Hypertension is well recognized as a risk factor that is associated with an increased incidence of stroke and myocardial infarction. The early detection of atherosclerosis is a real challenge and should be carried on at a cost and with a degree of risk and invasiveness that does not preclude its use in subjects with cardiovascular risk factors. For this purpose we have developed a non-invasive approach using a high resolution echotracking device making it possible to measure internal diameter and wall thickness of conduit arteries as well as their biomechanical properties. We present here a methodological overview of the system with a brief clinical study addressing the biomechanical properties of a medium size artery in hypertension as compared with normotension.

Arteries↗