[Helical x-ray computed tomography of renal arteries. Apropos of 300 patients]. / Angioscanographie hélicoïdale des artères rénales. A propos de 300 patients.

PURPOSE: To evaluate the role of helical CT angiography (CTA) in the detection of renal artery stenosis in hypertensive patients. MATERIALS AND METHODS: We studied 300 hypertensive patients (50 prospectively and 250 consecutively) with CTA and arteriography (n = 118). Helical acquisition (collimation 3 mm; pitch = 1, 20 seconds acquisition time) was performed 20-45 seconds after contrast injection (300 mgl/ml; 120 ml, 4 ml/sec). Transverse axial views and 3D reconstructions were analyzed (360 degrees interpolation algorithm, 1 mm overlapped). RESULTS: In the prospective series, CTA sensitivity was 100% for main renal artery stenoses and specificity was 98.2%; however 7/32 renal accessory arteries were not visualized. In the 300 patients studied, seventy-four stenoses were detected. There were 5 false-positive and 5 false-negative studies. Secondary hypertension was detected in 26% of patients (including 14 cases of adrenal hyperplasia). CONCLUSION: CTA is a promising technique for the detection of renal artery stenosis in hypertensive patients.

Signal-averaged electrocardiography in healthy children: influence of age, body size, and gender.

Our objective was to determine influence of age, body size, and gender on SAECG signals and to establish normal range for standard SAECG parameters in the pediatric population. Five hundred thirty healthy children and adolescents (290 males, 240 females) aged 6.0-17.3 years were studied with high resolution ECG. Patients were divided into five age groups, and each age group was divided in two subgroups according to gender. Parameters studied were filtered QRS duration, root mean square (RMS) voltage of the last 40 ms and of the last 30 ms of the filtered QRS complex, and duration of the terminal waveform of the filtered QRS < 40 microV of amplitude (LAS). After validation of the distribution of the various variables, means, standard deviations, and 95% confidence intervals were determined for each SAECG parameter at 25- to 250-Hz filtering and at 40- to 250-Hz filtering for the ten subgroups. There was a significant age and body surface area (BSA)-associated increase in filtered QRS duration in boys and girls, and a decrease in RMS voltage of the end of the QRS complex in girls. In addition, girls had a significantly shorter QRS and longer LAS durations than boys. These differences of signal-averaged signals between genders were not related to age or body size differences since analysis of covariance with age at evaluation or BSA as covariates showed the same trend. Three children (0.6%) had a SAECG out of normal range for age for the four parameters studied either at 25- or 40-Hz high pass filter. Due to the large sample studied, our results provide a basis for interpretation of SAECG in children. Normal ranges for the various variables were determined, and it appeared that adjustments for age, body size, and gender are mandatory when studying SAECG in children.

Helical CT angiography compared with arteriography in the detection of renal artery stenosis.

OBJECTIVE: The aim of the study was to improve the accuracy and detection rate for renal vascular lesions on helical CT angiography with an improved acquisition protocol and postprocessing. SUBJECTS AND METHODS: Fifty hypertensive patients (man age, 53 years old) referred because of clinical suspicion on renal artery stenosis were prospectively studied with digital renal arteriography and helical CT angiography. A 20-sec helical scan (collimation, 3 mm; pitch, 1) was obtained after injection of contrast medium. Interpretation was base on transverse sections, shaded-surface-display and maximum-intensity-projection reconstructions, and two-dimensional multiplanar reconstruction cuts obtained from shaded-surface-display reconstructions. RESULTS: Arteriography visualized 131 renal arteries (including 32 accessory arteries). Sixteen had significant (greater than 50% in diameter) stenosis. On helical CT angiography, 14 of these 16 stenoses were detected; two were missed (false-negatives), and two additional stenoses (false-positives) were reported. Sensitivity and specificity were 88% and 98%, respectively. Considering only main renal arteries, the sensitivity and the specificity of helical CT angiography were 100% and 98%, respectively. Helical CT angiography detected Conn's syndrome, which was responsible for hypertension, in two other patients. CONCLUSION: The accuracy and detection rate for renal artery stenosis on helical CT angiography compared with arteriography is improved with the described protocol.

[Cardiac involvement in Kugelberg-Welander disease. A prospective study of 8 cases]. / Evaluation cardiaque dans la maladie de Kugelberg-Welander. Etude prospective de 8 cas.

Kugelberg-Welander disease is a juvenile form of slowly progressive spiral amyotrophy in which the incidence of cardiac involvement is difficult to appreciate as cases are sporadic. Classically, it presents with atrial hyperexcitability with variable degrees of atrioventricular block. In order to assess the prevalence of cardiac involvement in this condition, the authors undertook a prospective study in 8 patients with Kugelberg-Welander disease. All underwent clinical and paraclinical examinations to assess cardiac function and rhythm. Doppler echocardiography, myocardial scintigraphy with Thallium 201 and Technetium99m, resting ECG. 24 hour Holter monitoring and signal averaged ECG were performed in all cases. This unique study detected one patient with infraclinical disease of the conduction system who became symptomatic during the follow-up period and required definitive cardiac pacing. During the study, one 20 year old man with Kugelberg-Welander disease was admitted to hospital with dilated cardiomyopathy with a fatal outcome. Because of the small number of patients and after a review of the literature, this study is to be continued to obtain a more accurate evaluation of cardiac involvement in this neuromuscular disease.

[Screening of renal artery stenosis: which patients, by what methods?]. / Dépistage des sténoses de l'artère rénale: chez quels patients, par quelles méthodes?

Renal artery stenosis may be caused by either atherosclerosis or fibromuscular dysplasia, and is responsible for hypertension or renal failure. Universal screening of all hypertensive patients is not recommended because of the relatively low prevalence of the disease. A selective approach is needed. The detection of renal artery stenosis requires noninvasive tests with a high predictive value (Doppler ultrasonography, intravenous angiography, spiral CT angiography, captopril renography) in patients in whom hypertension is severe, refractory to therapy, or associated with progressive renal insufficiency. Yet, after such screening, arteriography remains the gold standard of detecting and quantifying renal artery stenosis.

A prospective study of helical computed tomography angiography versus angiography for the detection of renal artery stenoses in hypertensive patients.

OBJECTIVE: To compare helical computed tomography angiography with arterial digital subtraction angiography in the diagnosis of renal artery stenoses. METHODS: Fifty hypertensives (24 men; mean age 53 years) were prospectively studied with computed tomography (Somaton Plus S, Siemens) and digital angiography (double-blind evaluation). Computed tomography was performed both in the sequential (the length of the abdomen) and in the helical (6 cm around renal arteries) modes during injection of 120 cm3 contrast medium. RESULTS: Digital angiography visualized 16 significant (< 50% on quantitative angiography) stenoses (16/131 renal arteries, including 32 accessory), in 14 (28%) patients. On helical computed tomography, 16 stenoses were detected, in 49 patients (16/122 renal arteries, seven accessory arteries were not identified because they were located out side the scan area); two patients had false-positive helical computed tomography results. The computed tomography sensitivity, specificity, positive and negative predictive values were 87.5% (14/16), 98.2% (111/114), 87.5% and 98.2%, respectively. In the sequential mode, two cases of bilateral adrenal hyperplasia, two aortic aneurysms and one renal neoplasm were detected. None of these patients had renal artery stenosis. CONCLUSIONS: Helical computed tomography is a suitable new non-invasive diagnostic modality for the detection of renal artery stenosis or adrenal pathology. With continued development and evaluation computed tomography could prove useful as a screening tool or as a replacement for digital angiography in patients with possible secondary hypertension.

[Non-surgical treatments of renal artery stenoses]. / Traitements non chirurgicaux des sténoses de l'artère rénale.

Management of patients with renal artery stenoses is aimed at normalizing or reducing blood pressure and correcting or preventing reduced glomerular filtration. The results of renal revascularization have been documented mainly in retrospective, uncontrolled reports in which blood pressure improvement was overestimated due to the placebo effect and optimization of drug treatment, the latter being frequently required despite adequate revascularization. In an overview of 10 series reporting blood pressure outcome following percutaneous angioplasty, cure rates were 50% in patients with fibrodysplastic stenosis but only 19% in those with atherosclerotic stenosis. The literature on revascularization of atherosclerotic stenosis with progressive renal failure shows that 55% of patients have improved renal function following surgery and 41% following angioplasty. Mortality is 6 and 5% respectively. The first controlled trials comparing revascularization to medical treatment in renal artery stenosis have recently been published. In a prospective randomized trial, Weibull et al. compared percutaneous angioplasty and surgery in 58 patients with unilateral atherosclerotic stenosis. Although 17% of the patients initially treated with angioplasty required subsequent surgery, blood pressure, renal function and renal artery patency rate did not differ between angioplasty and surgery 24 months after treatment. A Scottish group reported a prospective randomized trial of percutaneous angioplasty vs. medical therapy in patients with bilateral or unilateral atherosclerotic stenosis. In the bilateral group (n = 28), the drop in systolic pressure was significantly larger following angioplasty than following medical therapy, but diastolic pressure and creatinine did not differ after 24 months. In the unilateral group (n = 27), there were no differences in blood pressure or creatinine levels following angioplasty or medical therapy. Several randomized trials comparing angioplasty and conservative treatment or angioplasty and stent placement in patients with renal artery stenosis and normal or reduced renal function are currently underway. They should provide additional information regarding the risk/benefit ratio of these procedures.

[Evaluation of spiral computed tomography of the renal arteries alone or combined with Doppler ultrasonography in the detection of renal artery stenosis. Prospective study of 114 renal arteries]. / Evaluation du scanner spiralé des artères rénales seul ou couplé à l'écho-doppler dans le dépistage de sténoses rénales. Etude prospective sur 114 artères rénales.

A renovascular etiology occurs in 0.2 to 2% of hypertensive patients. Recently, spiral computed tomography (CT) has evolved as a new minimally invasive tool for the diagnosis of vascular pathologic conditions. The purpose of this study was to compare both spiral CT and color Doppler ultrasonography (US) with intraarterial digital subtraction angiography (DA) in the detection of renal artery stenosis (RAS) in hypertensive patients. Between December 1993 and April 1994, 44 hypertensives (men 22, mean age 52 years) suspected secondary hypertension were prospectively studied with spiral CT (Somatom Plus S, Siemens) US (Acuson, 3.5 MHz probe) and DA (double-blind evaluation). DA visualized 11 significant (> 50%) stenoses (11/114 renal arteries, including 27 accessory). On spiral CT, 9/11 were detected and 2 additional stenoses considered false positive. On US 5 stenoses were detected whereas 11 were demonstrated by DA; 2 patients had false positive US results. [table: see text] We conclude that combined spiral CT and color Doppler ultrasonography is an effective and relatively non invasive alternative to intraarterial digital angiography for the detection of renal artery stenosis in a hypertensive population screened for renovascular hypertension.

[Effects of bisoprolol and ramipril on short-term variability of systolic blood pressure during mental stress test: spectrum analysis]. / Effets du bisoprolol et du ramipril sur la variabilité à court terme de la pression artérielle au cours d'un test de stress mental: analyse spectrale.

UNLABELLED: The mid frequency component (MFC = 66-128 mHz) of blood pressure is an index of sympathetic vascular control. To investigate the effect of bisoprolol (B) and ramipril (R) treatment (TT) on the short-term variability of systolic blood pressure (SBP) diastolic blood pressure (DPB) and heart rate (HR) reactivity during mental stress, we studied 54 mild essential untreated hypertensive patients (24 men, 45 +/- 9.6 years, BP > 160/90 mmHg after a 15-days placebo run-in period) who were randomly assigned to double blind treatment (B: 10 mg/day: n = 28 and R: 5 mg/day: n = 26). A Stroop Word Color Conflict Test (SWCCT) was performed before and after 2 months of treatment. Hemodynamic parameters (BP and HR) were measured by a non invasive device (Finapres 2300E, Ohmeda-Maurepas) and underwent spectral analysis (SBP: mmHg.Hz-1/2, HR: beats/min.Hz-1/2, Anapres 1.2, Notocord-Orgametrie Systems, Igny-Lille) at rest and during SWCCT. The sympathetic vascular activity was assessed by calculating the area of the mid-frequency component (MFC = 66-128 Hz). RESULTS: [table: see text] CONCLUSION: The absolute variations in sympathetic activity during SWCCT as demonstrated by analysis of MFC of SBP and HR is not affected by chronic ramipril treatment, whereas bisoprolol attenuates sympathetic reactivity during SWCCT.

[Blood pressure variability and stimulation tests: value of the Stroop word color conflict test]. / Variabiilité tensionnelle et tests de stimulation; intérêt du Stroop word color conflict test.

OBJECTIVES: To study the modifications of the BP and its short-term variability in hypertensives patients submitted at to a psychological stress test. DESIGN AND METHODS: Fourty nine hypertensive subjects (27 women and 22 men, aged 46 +/- 9, SBP 164 +/- 10, DBP 97 +/- 6 mmHg after a 15 days placebo run-in period) were studied. We used the original version of Stroop Word Color Conflict Test (SWCCT) to induce mental stress. Haemodynamic parameters (SBP, DBP, MPB and HR) were measured continuously by a non invasive method (Finapres) with data acquisition every 0.5 second allowing spectral analysis of SBP variability at rest, during and after SWCCT (FFT algorithm on 256 point time series Anapres 1.2). RESULTS: All haemodynamic parameters increased during stress test (p = 0.001). The mean value and the variability (V) of SBP standard deviation (SD) increased during SWCCT (p = 0.001 and p = 0.003 respectively). Two minutes after the test, SPB returned to the rest level, while the overall variability of SPB remained elevated (p = 0.007). Spectral analysis: the total area under the curve and the mid frequency component (MFC) (66-128 mHz) increased during and after SWCCT (p = 0.001). [table: see text] CONCLUSION: Short-term variability of SBP is increased in hypertensives when submitted to a SWCCT appears to induce sustained orthosympathetic stimulation as suggested by the increase of mid frequency component (Mayer waves).

[Stress, blood pressure reactivity and arterial hypertension: not an unambiguous relation]. / Stress, réactivité tensionnelle et hypertension artérielle: une relation non univoque.

UNLABELLED: In order to determine the different ways the hypertensives' blood pressure would react during mental stress, 49 patients, 27 women and 22 men, were submitted at the Stroop Word Colour Conflict Test. Their haemodynamic parameters were recorded by finger photoplethysmography (Finapres device), with equidistant sampling (2 Hz). Temporal and spectral analysis showed evidence of: a quick and short elevation of BP and HR and a greater variability of SBP, as shown by the increase of the MF (66-128 mHZ) module. Patients can be divided into 3 clusters according to the reactivity of SBP. Group I (N, mean +/- sigma) 13, + 32.7 +/- 8 mmHg; group II 24, + 10.3 +/- 6; group III 12, -10.2 +/- 7. They were comparable on anxiety level and on any demographic and clinical feature. In group III, the higher NA at rest, the bigger the fall of SBP when stressed. The cognitive efficiency of these patients is increased by stress. Spectral analysis: Mid frequency (66-128 mHz) components are markedly higher in group III, before, during and after SWCCT showing a higher sympathetic tonus. CONCLUSION: The reactivity of BP is not homogeneous. One fourth of our patients showed a decrease of SBP during the cognitive treatment stage of the test without showing a decrease of sympathetic tone. Anxiety level is not predictive of BP's response.

[Preventive treatment of systemic embolic complications of atrial fibrillation]. / Le traitement prophylactique des complications emboliques systémiques de la fibrillation auriculaire.

Non-valvular atrial fibrillation multiplies the risk of presumed embolic events by a factor of four. The hemorrhagic risk of anticoagulant treatment varies considerably and its prophylactic efficacy was not tested in any randomised trial before the end of 1989. The recommendations of experts at that time recognised that data were inadequate. The publication since of four randomised trials involving 3,049 patients has provided a more objective base for management decisions, highly in favour of the anticoagulation of cases of non-isolated atrial fibrillation in the absence of contraindications.