[Why Coronary CTA will affect the diagnosis and management of stable coronary artery disease?]. / Pourquoi l'angioscanner va transformer les habitudes dans le diagnostic et la prise en charge de la maladie coronaire stable?

Until recently, the optimal work-up of patients with stable coronary artery disease (CAD) was based on non-invasive functional tests. Coronary CTA (CCTA) now challenges this standard work-up due to its efficacy to exclude significant coronary artery disease. Current indications for CCTA include symptomatic patients with intermediate pre-test probability of CAD with altered ECG (LBBB, repolarization abnormalities) rendering stress tests useless or patients unable to achieve sustained stress effort, and patients with indeterminate or uninterpretable results on ischemic work-up. A more agressive position is to consider CCTA as the cornerstone of patient management because the limitations and pitfalls of non-invasive techniques open the door to an alternative diagnostic imaging technique, either alone, or in combination with other Imaging techniques after reorganizing the sequence of imaging work-up. Without dismissing the dogma of initial détection of CAD along with prognostic stratification using functional tests, the recent availability of a minimally invasive anatomical test in the management of patients with stress angina, given the known limitations of traditional tests, changes the standard work-up algorithms. This suggests that the diagnostic work-up of patients with CAD is likely to be modified to increase the rôle of CCTA.

[Carotid Stenting in France after the EVA 3S and SPACE publications]. / Stenting carotidien en France après les publications d'EVA 3S et de SPACE?

Angioplasty of stenoses of the carotid bifurcation is a revascularization procedure that is used successfully in many patients. With more than 10 years of experience now, the feasibility of carotid stenting has been demonstrated. Its distribution is highly variable depending on the country, with a mean penetration rate in Europe of 15% of the number of carotid revascularizations. However, the complication rate is highly variable from one series to another and depends on the type of patient treated and the operator's learning curve. The results of the first two randomized studies comparing endarterectomy and carotid stenting, EVA 3S in France and SPACE in Germany, have just been published. The conclusions of these studies only relate to symptomatic patients, who make up a small proportion of revascularized patients. At 30 days, the French study concluded that surgery was better, and the German study showed no advantage to stenting. The analysis of these results compared to other publications should make it possible to best define the current indications for carotid stenting.

Management of acute chest pain: A major role for coronary CT angiography.

Most patients presenting with acute chest pain (ACP) at the emergency unit do not have any marked electrocardiogram abnormalities or known history of heart disease. Identifying the few patients who have, or will actually develop acute coronary syndrome in this group that is considered to be at low risk, is an actual clinical challenge for emergency department physicians. In these patients, the goal of complementary non-invasive morphological or functional imaging tests is to exclude heart disease. The diagnostic values of coronary CT angiography include a sensitivity of 96% and a negative likelihood ratio of 0.09, which are highly contributory to the diagnosis, and the integration of this imaging test into a decision tree algorithm appears to be the least expensive strategy with the best cost/effective ratio. Coronary CT angiography is indicated in the presence of ACP associated with an inconclusive electrocardiogram, in the absence of any other obvious diagnoses, when the ultrasensitive troponin assay is negative or the dynamic changes are modest, slow and/or inconclusive. Ideally, coronary CT angiography should be performed within 3 to 48hours after the initial consultation.

Diagnosis and treatment of renin-secreting tumors. Report of three cases.

During the past 10 years, we have found renin-secreting renal juxtaglomerular cell tumors in three hypertensive patients (two women, one man, aged 22, 69, and 21 years, respectively). The major chemical and biological findings revealed the association of severe hypertension with hypokalemia and increased plasma renin activity and plasma aldosterone. The diagnosis of such tumors is difficult, and two of the three patients were followed up for four and five years respectively before undergoing surgery. The pharmacological blockade of the renin system by various agents (beta-blockers, angiotensin II antagonists, and captopril) and its effects on blood pressure and plasma renin activity proved to be unreliable. Renal venous catheterization for renin measurements failed to provide adequate localization of the tumor. Direct radioimmunoassay, however, showed the total plasma renin to be markedly elevated. In addition, renal arteriography showed an avascular area corresponding to the renin-secreting tumor in each of the three patients. All three patients were cured of hypertension and hypokalemia by excision of the tumor.

Angiographic and electron-beam computed tomography studies of retrograde cardioplegia via the coronary sinus.

Retroperfusion of the coronary sinus does not provide homogeneous distribution of cardioplegic solution. The goal of this study was to analyze the distribution of flow during retrograde cardioplegic infusion in cadaveric human hearts with two different techniques of coronary sinus cannulation: (1) internal occlusion of the coronary sinus by balloon inflation and (2) external occlusion by tightening the orifice of the coronary sinus around a simple catheter. To evaluate differences between the two techniques, angiographic and electron-beam computed tomographic studies were performed. Computed digital angiography was performed on 14 hearts. Angiographic patterns varied according to type of coronary sinus cannulation. With the balloon inflation technique, the marginal vein and the anterior descending vein were perfused first; the posterior descending vein was not perfused. This vein was opacified secondarily through a venovenous anastomosis located at the apex of the heart. Backward flow into the right atrium (steal phenomenon) was demonstrated. At completion of retroperfusion, the inferior part of the septum remained poorly opacified. Conversely, angiographic findings after external occlusion of the coronary sinus revealed simultaneous injection of all venous channels. The entire septum was well opacified at completion of retroperfusion. Electron-beam computed tomographic study was performed on eight hearts with the external occlusion technique and nine with the internal occlusion technique. The computed tomographic findings confirmed the results of digital angiography. The peak myocardial enhancement and the peak rising rate of myocardial enhancement within the interventricular septum were significantly more important (p < 0.0001) when the external coronary sinus occlusion mode was used than when the internal coronary sinus occlusion mode was used. In all hearts except one, the right ventricular wall was not opacified, regardless of the type of cannulation and the type of radiologic analysis. This study demonstrates the importance of coronary sinus cannulation technique in optimizing the protection of the interventricular septum with retrograde cardioplegic infusion.

Evaluation by electron beam computed tomography of intracardiac masses suspected by transoesophageal echocardiography.

OBJECTIVES: To assess the suitability of electron beam computed tomography (EBT) in evaluating and subsequently managing cardiac masses suspected as a result of examination by transthoracic and transoesophageal cross sectional echocardiography. DESIGN AND PATIENTS: In 76 consecutive patients with suspected cardiac masses, the impact of the EBT examination was analysed by reviewing whether EBT examination altered management by confirming or excluding a mass, whether EBT imaging substantially contributed to decision-making, and lastly whether EBT influenced the decision to operate on the patient. RESULTS: EBT modified the diagnosis or confirmed results which had been questionable with cross sectional echocardiography in 53 cases (70%): these cases included those with anatomical features such as dense calcifications or fatty structures (n = 20), lipomatous lesions (n = 5), equivocal thrombi (n = 5), pericardial masses (n = 5), or hydatid cysts (n = 2). EBT gave information over and above cross sectional echocardiography in all patients with malignant tumours (n = 16) by providing a better delineation of the relation between intracavity masses and normal structures, including the mural site of tumour attachment and tumour extension to the great vessels and the adjacent extracardiac mediastinal structures. EBT provided no additional information over cross sectional echocardiography in the remaining patients (n = 23), particularly in those with myxomas (n = 11) or small valvar lesions (n = 6). EBT only confirmed that the lesion was well demarcated, limited in extent, or not associated with a mass. CONCLUSIONS: EBT has considerable potential for clinical management and surgical planning and may help clinicians to decide against surgery, particularly in patients with unresectable tumours.

Photofrin II uptake by atheroma in atherosclerotic rabbits. Fluorescence and high performance liquid chromatographic analysis on post-mortem aorta.

Atherosclerotic lesions were induced in normal and Watanabe rabbits by atherogenic diet and stripping of aorta endothelium. The rabbits were injected with Photofrin II and sacrificed two days later. Atheromatous aorta as well as normal aorta from control animals were characterized by their fluorescence spectra using front face excitation. Characteristic emission peaks at 631 and 694 nm were displayed at atheromatous plaques. The excitation spectrum shows a strong band at 394 nm and weaker bands at 446, 504, 536 and 574 nm. Although no fluorescence of normal aorta can be seen by visual inspection, emission with a maximum at 626 nm was detected by spectrofluorimetry. Normal phase high performance liquid chromatography analysis of extracts from atheroma and control aorta were also carried out. The specific labelling of atheroma involves mainly protoporphyrin, hematoporphyrin and also minor components of Photofrin II which are accumulated. Some other components are accumulated but do not appear to be specifically retained by atheroma.

In vitro uptake of dicarboxylic porphyrins by human atheroma. Kinetic and analytical studies.

Human atheromatous aorta segments as well as presumably disease-free control aorta were obtained at autopsy. They were incubated with solutions of various purified dicarboxylic porphyrins including hematoporphyrin (HP) and hydroxyethylvinyldeuteroporphyrin (HVD), and with solutions of Photofrin. Selective labelling of the atheroma was shown by macroscopic and microscopic observations of the characteristic porphyrin fluorescence associated with the atheromatous plaques. The time dependence of the uptake, monitored by absorption spectrophotometry or by high performance liquid chromatography, was inferred from the disappearance of the porphyrins in the incubation medium. Significant binding was observed in the absence of albumin or serum proteins. The uptake of HP was less than that of the more hydrophobic compounds HVD or Photofrin when these porphyrins were used alone. The presence of albumin or serum drastically reduces atheroma labelling. Some competition between HP and HVD for binding sites is also seen. The present results do indicate that hydrophobic porphyrins have an intrinsic affinity for atheroma and that they can be taken up through passive processes. Taking into account previous data on animal models (Photochem. Photobiol. (1989), 731-737), it appears however that, in vivo, interactions with proteins and pharmacokinetics will primarily determine plaque labelling.

Cardiac metastatic melanoma investigated by magnetic resonance imaging.

There is a high rate of cardiac involvement in malignant melanoma (MM), but such cardiac metastases are usually diagnosed late. This report describes four cases with different clinical presentations of MM cardiac involvement that were investigated by magnetic resonance imaging (MRI). The MM cardiac involvement was asymptomatic in one case, detected because of a superior vena cava syndrome in a second, and because a tamponade in the remaining two cases. MRI permitted the diagnosis of cardiac metastases of MM, which was not made by echocardiography in one case. By precisely detecting the extent of the tumors, MRI was a great help in management, especially when an isolated cardiac metastasis was suitable for surgical ablation (two cases). Because both clinical signs and transthoracic echocardiogram are not very sensitive for diagnosing MM myocardial involvement, MRI can help provide such a diagnosis and ensure better treatment-monitored decisions.

Idiopathic dilatation of the pulmonary artery: report of four cases.

Idiopathic dilatation of the pulmonary artery (IDPA) is a rare congenital disease which is usually detected fortuitously on chest x-ray, thus radiologists must be aware of this clinical entity. This report describes four cases to which Magnetic Resonance Imaging (MRI) played a major role in diagnosing IDPA and in detecting the concomitant findings observed in this disease. MRI is a non-invasive procedure with many advantages for the accurate and reproducible measurement of artery structures, which makes it the preferred option for combined use with echocardiography in the diagnosis and follow-up of patients with IDPA.

Validation of a digital videodensitometric program analysis for measurement of left ventricular ejection fraction.

Left ventricular (LV) function was studied in 30 patients using digital subtraction angiography by the intravenous approach. Each ventriculogram was processed with a specific videodensitometric analysis to determine LV ejection fraction. The program was verified in an experimental set-up consisting of nine latex balloons filled with contrast medium. Its validation has been established by comparing videodensitometric results with classical results supplied by geometric methods. A good correlation was obtained (r = 0.9449) and, furthermore, with experimental models, videodensitometric analysis seemed to be more accurate than geometric analysis. Digital videodensitometry appears to be a valuable and accurate method for quantifying LV function, and a promising technique for determination of the real volumes.

New non-ionic contrast: effects on the cardiovascular system.

Contrast media cause a variety of effects on the cardiovascular system both hemodynamic and electrophysiologic in nature. These effects are mainly related to the physico-chemical characteristics of the compounds and are less pronounced with low osmolar nonionic than with ionic contrast media. Nonetheless there is still room for further improvement in the features of the nonionic agents. Iomeprol is a new nonionic contrast medium which, with its low osmolality and toxicity and very low viscosity, proved to be safe and well tolerated during clinical trials in cardioangiography.

Percutaneous transluminal angioplasty of stenotic lesions in dialysis vascular accesses.

Forty-five stenoses behind arteriovenous fistulas in 35' haemodialysed patients were treated with percutaneous transluminal angioplasty (PTA). Immediate stenoses dilatation results in relation to the AVF type were haemodynamically significant in 40 cases (88%), with poorer results on bovine heterograft stenoses. Dilatation results in relation to the site of the lesion showed haemodynamically efficient angioplasty on stenoses next to the anastomosis (67.5%) but a poor result on distal lesions (4 cases). We observed 4 cases of thrombosis but 2 recovered after treatment, one after local fibrinolytic perfusion one after surgical thrombectomy. Follow-up over a period of one to 18 months (mean 8 months) including angiography and appreciation of the dialysis quality were performed in 30 patients who had a successful dilatation. PTA appears to be a technically feasible and clinically effective method of treating stenoses lying on the venous limb fistula in patients on chronic haemodialysis.

[Severe ischemia of the lower limbs after ingestion of LSD]. / Ischémie sévère des membres inférieurs après ingestion de LSD.

A case of severe limb ischaemia predominating in the legs in a young female drug addict is reported. Arteriography revealed diffuse spasm of all arteries of the lower limbs associated with localised spasm along the profunda artery in particular. These appearances regressed on control angiography performed 10 days later. The treatment which associated volume expanders and intravenous vasodilatation agents (magnesium sulphate) led to rapid improvement in the clinical condition in 3 days. There were no long-term complications. The causative role of LSD was suggested by the history of greatly increased intake in the period before the onset of symptoms. LSD is a derivative of lysergic acid, the common nucleus of the derivative of the ergot of rye. Analysis of a sample dose taken by the patient showed a very large quantity of LSD and of lysergic acid and a very small amount of other ergot alkaloids known for their peripheral vasoconstrictor effects. The circumstances following peripheral ischaemia are discussed; the association of haschich - LSD does not seem to be a factor. The increased doses and a predisposed vascular system, in common with ergot containing drugs, seem to be the major factors.

[Mass and geometry of the left ventricle. Contribution of ultrafast computed x-ray tomography and magnetic resonance imaging]. / Masse et géométrie ventriculaire gauche. Apports de la tomodensitométrie ultrarapide et de l'imagerie par résonance magnétique.

Ultrafast computed tomography and magnetic resonance imaging are two new methods of cardiac imaging. Measurements of left ventricular volume (end-diastolic, end-systolic volume, stroke volume) and mass have been validated with both methods. The calculations are independent of the geometric shape of the ventricle. Although regional analysis is difficult because of the complex movement of the left ventricle in the tomographic cuts, these methods present a number of advantages: excellent temporospatial tomographic resolution, approximately the same in all dimensions, appreciation of endocardial movement from an epicardial centre, the potential to record their transform spatial data in 3 dimensions from initial planar acquisition. However, all potential regional measurements are still being validated as they are operator-dependent and require visual identification and manual tracing of the cardiac contours or local infrastructures which affect the results of these techniques which are still relatively little used in cardiac imaging. In the context of clinical evaluation, these relatively non-invasive methods will become extremely accurate in the appreciation of parameters of left ventricular geometry and function. They will become very useful in the determination of the myocardial effects of drugs, surgery or other interventional procedures in different models of cardiac disease.

[Quantification of left ventricular function by subtraction intravenous angiography]. / Quantification de la fonction du ventricule gauche par angiographie numérique par voie veineuse.

Digitised intravenous angiography (Diva), initially applied to the study of the aorta and great vessels, has benefited from technical advances, especially the possibility of recording 25 frames per second, which now allows studies of the heart itself. 22 subjects underwent angiography with digitised subtraction after injection of 50 ml of sodium diatrizoate and meglumine in the right atrium and selective left ventriculography in the same catheter session. The end diastolic and systolic indices and global ejection fractions were measured independently for each technique by Chapman's method by two observers. The model of digitised angiography used was a CGR Divas prototype functioning in the pulsed graphic mode at 25 images per second. The results showed that the Diva method gave reproducible values of the end diastolic index (101 +/- 29.8 and 104.5 +/- 30.7: r = 0.98), of the end systolic index (43.2 +/- 32.9 and 44.6 +/- 32.5; r = 0.98), and of the ejection fraction (62.5 +/- 17.16 p. 100 and 62.17 +/- 15.7 p. 100; r = 0.96). There was a close correlation between the results of Diva and selective ventriculography (end diastolic index: 97.8 +/- 21.1 and 101.6 +/- 10.3; r = 0.87; end systolic index: 38.82 +/- 24.8 and 43.9 +/- 21.17; r = 0.95; ejection fraction: 62.12 +/- 16.27 and 57.29 +/- 15.53; r = 0.95). There was a significant underestimation of the end systolic index using Diva (0.01 less than p less than 0.02). The originality of the pulsed graphic method is the totally digitised character of the data.(ABSTRACT TRUNCATED AT 250 WORDS)

[Value of numeric intravenous angiography in the study of coarctations of the thoracic aorta]. / Intérêt de l'angiographie numérique par voie veineuse pour l'exploration des coarctations de l'aorte thoracique.

The investigation of isthmic coarctation of the aorta comprises radiological opacification usually by a retrograde arterial approach. Digitised intravenous angiography (DIVA) is a new way of carrying out this task by a relatively simple and non-invasive technique. We investigated 32 patients with this method and now present our results: the investigation was performed for suspected coarctation in 22 cases and for postoperative assessment in 10 cases. The equipment used was characterised by a variable rate of acquisition from 1 to 3 images per second with a 512 X 512 matrix. The investigation consisted in an intravenous injection of 50 to 100 ml of contrast, usually via a peripheral vein (87.5 p. 100). Overall, DIVA demonstrated the coarctation or the appearances of the site of operation in 97 p. 100 of cases. This high success rate was related to the study population: young cooperative patients capable of maintaining apnoea and remaining still during the procedure. In the 21 patients referred for suspected coarctation (excluding the only failure of the series), the diagnosis was confirmed and the site of coarctation accurately located. The degree of stenosis was assessed subjectively: appearances of the site of coarctation, importance of the collateral circulation. In addition, a videodensitometric study, i.e. a study of the variations of the patterns of grey with respect to time, was carried out in 4 patients; in severe coarctation, a delay of about 4 seconds in the opacification of the zone distal to the stenosis was observed. This analysis is still at the experimental stage, but it may eventually allow reliable quantification of the degree of stenosis.(ABSTRACT TRUNCATED AT 250 WORDS)

[Early angiographic evaluation of coronary bypass using arterial grafts]. / Evaluation angiographique précoce des pontages coronaires par greffons artériels.

The aim of this study was to evaluate the early postoperative angiographic features of arterial coronary bypass grafts in 83 asymptomatic patients referred consecutively from the surgical unit. The patients aged 33 to 78 years (average 62 years) were operated between August 1989 and March 1992 and received only arterial coronary bypass grafts: 209 arteries bypassed (121 internal mammary including 10 sequential grafts, 46 radial, 36 epigastric including 4 sequential grafts and 6 gastroepiploic arterial grafts), an average of 2.4 bypass grafts per patient. Selective angiography of the arterial grafts was performed systematically between the 7th and 15th postoperative days in patients with uncomplicated recoveries. The native coronary arterial network was opacified only when a graft was "non-functional": haemodynamic (> 70%) stenosis or occlusion. 3.8% of pediculated mammary grafts were occluded. On the other hand, 16.6% of free internal mammary grafts were occluded. None of the radial artery grafts were occluded, but 8% were stenotic. Finally, 30% of epigastric and 50% of the gastroepiploic grafts were occluded. These results confirm the good function of in situ mammary artery grafts by suggest that systematic multiple arterial grafts should be used with caution. Radial artery grafts give very encouraging results which require long-term evaluation. Early postoperative evaluation of coronary arterial grafts provides important information and should be considered a routine procedure.

[Left ventricular thrombus revealed by electron bean computed tomography, in a patient with antiphospholipid syndrome]. / Thrombus de la pointe du ventricule gauche révélé par le scanner à faisceau d'électrons, chez une patiente atteinte d'un syndrome des antiphospholipides.

The authors report a case of a 48 year old woman admitted to hospital because of digital ischemia, in a context of antiphospholipid syndrome. The electrocardiogram-triggered electron beam computed tomography revealed an apical thrombus associated with a thinning left ventricular wall, suggesting painless myocardial infarction. The diagnosis was secondary confirmed by coronarography.

[Hypoxemia after heart surgery by a right-left shunt via a permeable unrecognized foramen ovale]. / Hypoxémie après chirurgie cardiaque par shunt droite-gauche à travers un foramen ovale perméable et méconnu.

Hypoxemia is a relatively common complication in the immediate postoperative period after cardiac surgery under cardio-pulmonary bypass, usually due to pulmonary disease. When this does not improve with oxygen therapy and in the absence of pulmonary disease, it may be due to a right-to-left shunt. We report a case with a right-to-left intracardiac shunt due to persistence of a patent foramen ovale, which became functional again under the new hemodynamic conditions after surgery under cardiopulmonary bypass and assisted ventilation. The diagnosis and physiopathological mechanism were studied by cardiac catheterisation and angiography. Contrast echocardiography should be able to detect these acquired shunts relatively easily. The diagnosis requires appropriate therapy: discontinuation of ineffective assisted ventilation as this may aggravate the situation by increasing pulmonary resistance, and anticoagulant therapy to prevent potentially disastrous paradoxical thromboembolism.