No post-conditioning in the human heart with thrombolysis in myocardial infarction flow 2-3 on admission.

AIMS: Proof-of-concept evidence suggests that mechanical ischaemic post-conditioning (PostC) reduces infarct size when applied immediately after culprit coronary artery re-opening in ST-elevation myocardial infarction (STEMI) patients with thrombolysis in myocardial infarction 0-1 (TIMI 0-1) flow grade at admission. Whether PostC might also be protective in patients with a TIMI 2-3 flow grade on admission (corresponding to a delayed application of the post-conditioning algorithm) remains undetermined. METHODS AND RESULTS: In this multi-centre, randomized, single-blinded, controlled study, STEMI patients with a 2-3 TIMI coronary flow grade at admission underwent direct stenting of the culprit lesion, followed (PostC group) or not (control group) by four cycles of (1 min inflation/1 min deflation) of the angioplasty balloon to trigger post-conditioning. Infarct size was assessed both by cardiac magnetic resonance at Day 5 (primary endpoint) and cardiac enzymes release (secondary endpoint). Ninety-nine patients were prospectively enrolled. Baseline characteristics were comparable between control and PostC groups. Despite comparable size of area at risk (AAR) (38 ± 12 vs. 38 ± 13% of the LV circumference, respectively, P = 0.89) and similar time from onset to intervention (249 ± 148 vs. 263 ± 209 min, respectively, P = 0.93) in the two groups, PostC did not significantly reduce cardiac magnetic resonance infarct size (23 ± 17 and 21 ± 18 g in the treated vs. control group, respectively, P = 0.64). Similar results were found when using creatine kinase and troponin I release, even after adjustment for the size of the AAR. CONCLUSION: This study shows that infarct size reduction by mechanical ischaemic PostC is lost when applied to patients with a TIMI 2-3 flow grade at admission. This indicates that the timing of the protective intervention with respect to the onset of reperfusion is a key factor for preventing lethal reperfusion injury in STEMI patients. CLINICAL TRIAL NUMBER: NCT01483755.

Planned caesarean in the interventional radiology cath lab to enable immediate uterine artery embolization for the conservative treatment of placenta accreta.

AIM: To evaluate the feasibility and efficacy of routine uterine artery embolization (UAE) immediately after planned caesareans performed in the cath lab for conservative treatment of placenta accreta. MATERIALS AND METHODS: A retrospective study included all patients who had a planned caesarean in the cath lab for conservative treatment of placenta accreta at Angers University Hospital, which is a tertiary care centre, from April 2001 to September 2010. Twelve patients underwent UAE immediately after caesarean with the placenta left partially or totally in situ. The success rate of embolization, blood loss, and complications were reported. RESULTS: Diagnosis of abnormal placentation was confirmed by caesarean findings in 14 cases. Four patients had a percreta form with bladder invasion. In seven cases blood loss was insignificant and UAE was prophylactic; no secondary haemorrhage was observed in this group. Postpartum haemorrhage occurred in five cases: control of immediate postpartum bleeding by embolization was successful in three and failed in two leading to hysterectomy. In one case uterine necrosis occurred 6 weeks after embolization, requiring a hysterectomy. Delayed complications resulted in hysterectomy and partial bladder resection 3 months after delivery for one of the patients with placenta percreta. CONCLUSION: UAE immediately after a caesarean performed in the cath lab is a feasible therapeutic option for conservative treatment of placenta accreta. Advantages include reducing stress and risks associated with transferring women with potentially unstable haemodynamics.

Carotid rete mirabile and pseudoxanthoma elasticum: an accidental association?

We report the case of a young female patient with a transient amaurosis due to a carotid rete mirabile (CRM), a rare congenital carotid malformation, and pseudoxanthoma elasticum (PXE), an inherited autosomal recessive systemic metabolic disorder characterised by fragmentation and mineralisation of elastic fibres in connective tissues (skin, eyes) and the vascular system. CRM is a rare form of intracranial carotid malformation whose association with PXE (6 cases at present) would appear not to be accidental. This observation suggests a new link between congenital arterial remodelling and the PXE.

[Cystic and cavitary lesions of the lung: imaging characteristics and differential diagnosis]. / Kystes et cavités du poumon: description sémiologique et approche étiologique.

Gas containing lesions of the lung can be differentiated into cystic and cavitary lesions based on their imaging characteristics, which is helpful for differential diagnosis. The imaging features include number, size, thickness and smoothness of the walls, content, lesion distribution and occasional associated lesions. Some imaging features have characteristic diagnostic implications: mural nodule and meniscus sign. Cysts are characterized by thin and regular walls, less than 2 mm in thickness. The differential diagnosis includes: histiocytosis X, lymphangioleiomyomatosis, cystic metastases, septic emboli, pulmonary sequestration. Emphysema, honeycombing and cystic bronchiectases should also be considered. Cavitary lesion have thicker walls. The most frequent etiologies include abscess, cavitary tumors, mycobacterial infections and fungal infections.

[Dose reduction during CT coronary angiography]. / La réduction de dose en coroscanographie.

Dose delivery during CT coronary angiography with retrospective ECG gating is high especially due to the important slice overlapping. Optimization of the acquisition parameters is necessary to reduce patient exposure. First, the height of the scan field should be limited to the heart. Both kV and mA should be adjusted based on patient morphology. ECG gated exposure modulation with mA reduction during systole, a technique most applicable for patients with slow and regular heart rate, can result in a dose reduction up to 50%. The use of prospective ECG gating can also reduce patient dose. This technique also requires patients with slow and regular heart rate.

[MR imaging of coronary arteries: noncontrast free-breathing whole heart acquisition with ultrafast 3D balanced gradient-echo technique]. / Imagerie par résonance magnétique des artères coronaires: acquisition "coeur entier", en respiration libre, sans injection d'agent de contraste et utilisant la séquence 3D en écho de gradient balancé ultrarapide.

The 3D balanced gradient-echo technique is described along with th eimaging protocol for MR imaging of th ecoronary arteries. A 3D volume with spatial resolution of 0.6 x 0.6 x 0.75 mm composed of 140 slices covering the whole heart is acquired over 10 minutes. The main advantage of this whole heart technique is the possibility to image the coronary arteries along their entire course in a single acquisition. Selection of the navigator positions, timing of image acquisition and its duration through the R-R interval are the main factors requiring optimization.

[Virtual interventional radiology: evaluation of performances as a function of experience]. / Réalité virtuelle en radiologie vasculaire interventionnelle: évaluation des performances de l'opérateur selon son niveau d'expérience.

PURPOSE: To determine the value of an angioplasty simulation to differentiate the users based on their level of experience. To determine the perceived usefulness of an angioplasty simulation program. MATERIALS AND METHODS: Forty-six radiologists performed a renal angioplasty on a VIST simulator (Mentice Corporation, Gothenburg, Sweden); the procedure was completed by 41 radiologists. The radiologists were divided into two groups based on the level of experience. Quantitative variables analyzed included procedure duration time and fluoroscopy time. The radiologists then completed a questionnaire evaluating the simulation program. RESULTS: Radiologists with more than 2 years of clinical experience (n=14) performed the procedures faster (20.4 min vs 27.4 min, p<0.01) using less fluoroscopy time (7.8 min vs 11.2 min, p<0.05) than others. Radiologists performing more than 2 procedures per month (n=14) performed the procedures faster (19.4 min vs 27.9 min, p<0.01) using less fluoroscopy time (7.4 min vs 11.3 min, p<0.05) than other (n=27). The participating radiologists indicated that the simulation was realistic. CONCLUSION: Procedure duration time and duration of fluoroscopy were criteria able to differentiate the users based on their level of experience. The educational value of the simulation program was perceived as helpful by the users.

[Contrast enhanced MR angiography: evolving towards whole-body real time acquisitions]. / Angiographie par résonance magnétique avec injection de produit de contraste: évolution vers le corps entier et le temps réel.

MRA includes all techniques used to depict vessels with MR. Gadolinium contrast injection combined with gradient echo sequences is the technique of choice for vascular imaging. Technical advances now allow faster acquisitions. The purpose of this article is to present two main advances with MRA: whole-body MRA and dynamic 3D MRA. Technical considerations, acquisition techniques, advantages and pitfalls based on our experience with a 1.5T MR unit will be discussed in order to promote their use in routine clinical practice.

[Cardiac MRI: technical considerations]. / Les conditions techniques d'utilisation de l'IRM cardiaque.

Establishing a clinical cardiovascular magnetic resonance imaging (MRI) program needs a dedicated technical surroundings as well as a specific and expert staff. These guidelines based either on proofs or on expert consensus are stated in order to help the physicians to reach or maintain the competence required for clinical use of cardiovascular MRI. After the general safety statements, the guidelines are focused on hardware and software requirements, the MRI sequences and views, the post-acquisition analysis, and the staff. Specific safety concerns are then approached, more particularly stress testing MRI.

ST2 as a predictor of late ventricular remodeling after myocardial infarction.

Out of 163 STEMI patients, 33 presented left ventricular remodeling (LVR) as assessed by multiple cardiac magnetic resonance (CMR) scans. LVR patients were identified as EarlyLVR (LVR occurring between baseline and 3 months) or LateLVR (LVR occurring between 3 months and one year), and matched to non-remodeler patients in term of age, gender, anterior infarction, baseline LV ejection fraction and infarct size. ST2 and NT-proBNP were measured at baseline and 3 months. Systolic wall stress (SWS) was calculated by CMR. At baseline, mean levels of ST2, NT-proBNP and SWS were 67.1 ±â€¯54.1 ng/mL, 1529 ±â€¯1702 ng/L and 17.9 ±â€¯7.1 103 N·m-2, respectively, and did not differ among the groups. At 3 months, EarlyLVR patients presented significant higher ST2, NT-proBNP and SWS (31.6 ±â€¯12.7 ng/mL, 1142 ±â€¯1069 ng/L, 25.5 ±â€¯9.7 103 N·m-2), compared to the corresponding non-remodelers (20.5 ±â€¯8.6 ng/mL, 397 ±â€¯273 ng/L, 18 ±â€¯7.3 103 N·m-2; with p = 0.017, 0.040, and 0.036, respectively). LateLVR patients presented higher ST2 at 3 months than their non-remodelers (33.6 ±â€¯15.9 versus 23.66 ±â€¯8.7 ng/mL, p = 0.046), while NT-proBNP and SWS were not different between groups at both timepoints.

[Usefulness of magnetic resonance angiography in the screening of renal artery stenosis in hypertensive patients: proposition of a diagnostic algorithm: a study of 245 patients]. / Apport de l'angiograpliie par résonance magnétique pour le dépistage de ia sténose artérielle rénale cliez le palient fiypertendu. Proposition d'un organigramme diagnostique: étude de 245 patients.

Usefulness of magnetic resonance angiography in the screening of renal artery stenosis in hypertensive patients: proposition of a diagnostic algorithm: a study on 245 patients. Different non-invasive techniques, including Duplex, spiral angioscan, and magnetic resonance angiography (MRA) are available for the diagnosis of renal artery stenosis (RAS). The aim of this study was to assess the diagnostic performances of MRA and the MRA-Duplex couple in the diagnosis of RAS. Between September 2003 and January 2005, 245 patients benefited from a renal MRA for the assessment of hypertension etiology. The MRA-Duplex couple was performed in 228 patients. Renal arteriography was performed in case of abnormalities observed with MRA and/or Duplex (n=41). The sensitivity and specificity of MRA were respectively at 100% and 23%. The sensitivity was notably higher in the right renal artery (100 vs. 73%). The sensitivity and specificity of Duplex were respectively at 71 and 85%. The concordance between the two exams was disappointing (kappa at 0.39 for the right side and 0.62 for the left side), leading to the interest of the MRA-Duplex association for excluding the presence of RAS (sensitivity and negative predictive value=100%). However, using the MRA-Duplex couple led to a high number of false positive cases, due to MRA, leading to 11 angiograms out of 41 exams, without any significant RAS. In case of suspicion of RAS, the MRA-Duplex couple permits to exclude definitely the diagnosis of RAS. In case of discordance between the 2 exams, it would be useful to require a spiral angioscan and/or redo a Duplex exam using contrast agents, prior to angiography with a therapeutic goal. These management modalities might be useful to avoid the number of normal angiograms, with an inherent risk of complications and cost excess.

Imaging of thoracic aortic injury.

Isthmic aortic rupture or disruption should be systematically sought when there is high kinetic energy trauma to the thorax. This condition is extremely serious and life threatening. It needs to be diagnosed rapidly but diagnostic pitfalls must be avoided. CT angiography is the standard examination. The main CT signs of rupture or disruption of the thoracic aorta are periaortic hematoma, intimal flap, pseudo-aneurysm and contrast agent extravasation. There are three types of lesion: intimal, subadventitial or pseudo-aneurysmal, and complete rupture with lesion of the three tunicae, and it is important to grade them for better therapeutic management. The main diagnostic pitfalls of the CT scan are the presence of a ductus diverticulum and post-isthmic fusiform dilatation. Associated lesions must not be overlooked. The most common are ruptures of the aortic root and the thoracic aorta in the diaphragmatic hiatus.

Renal artery vasomotion: in vivo assessment in the pig with intravascular Doppler.

Intravascular Doppler is widely used for experimental studies in the coronary circulation. We designed this study to assess baseline bloodflow and arteriolar resistance in the porcine renal circulation and to study the vasomotor responses of vasoactive drugs. In anesthesized piglets (n = 15), renal arterial diameter was measured with quantitative angiography and blood flow velocity with a Doppler wire (Cardiometrics). Bloodflow and resistances were calculated at baseline and after injection of vasoactive drugs (isosorbide dinitrate, papaverine). This allowed us to determine the renal bloodflow reserve (the capacity of the kidney to augment basal bloodflow). Injection of isosorbide dinitrate was associated with an increase in average peak velocity of 64% (P < 0.01) and a small (from 4.5 to 4.74, P < 0.01) but significant increase in renal artery diameter, resulting in an increase in bloodflow of 82% (P < 0.01) and a decrease in arteriolar resistance of 46% (P < 0.01). Bloodflow returned to baseline (4.76 +/- 1.48 mL/s) approximately 5 min after isosorbide injection. Average Peak Velocity increased almost twofold after papaverine injection (60 +/- 10 to 108 +/- 24 cm/sec, P < 0.01). There was a significant (P < 0.01) increase in arterial bloodflow of 96% in the right and 79% in the left renal artery after injection of papaverine with a corresponding significant (P < 0.01) decrease in arteriolar resistance of 49% in the right and 44% in the left renal artery. Using a combination of quantitative angiography and intravascular Doppler allows easy measurement of baseline renal blood flow and of the effects of vasodilator drugs on bloodflow and resistance. The results show that a vasodilatator reserve exists in the renal circulation but is less marked than that reported in the coronary circulation.

[Better understanding of atheromatous ischemic renal vascular disease]. / Mieux comprendre la pathologie vasculo-rénale ischémique athéromateuse.

Atheromatous ischaemic renal vascular disease (AIRVD) comprises ischaemic renal disease, atheromatous disease of the large arteries and intra-renal atheromatosis. Cholesterol emboli and lesions of nephroangiosclerosis are often associated, affecting the two kidneys. It is an increasingly common cause of chronic renal failure in an aging population, affecting 12 to 14% of new patients requiring dialysis in the United States. Atheromatous stenoses are very progressive with a risk of renal atrophy; they are a marker of polyvascular disease, often detected during other angiographic investigation. Hypertension secondary to the stenosis, still incorrectly called renovascular hypertension, is, however rare, affecting less than 0.5% of hypertensives. For economic reasons, it is important to select patients who need complementary investigation. In view of the absence of specific signs of the pathology, the "presumptive" diagnosis is based on a range of clinical and biological results, especially in a high risk context. The method of investigation varies from team to team, depending on the availability of equipment, the experience of the operators and the patient himself. Duplex Doppler, spiral angioscan and magnetic resonance angiography are the most pertinent investigations for the management of AIRVD. When the diagnosis of renal artery stenosis has been made, the problem of revascularisation, the objective of which is to preserve or restore the functional nephronic mass, has to be treated to prevent progression to end stage renal failure. Although epidemiological and physiopathological evidence is in favour of revascularisation, only renal salvage procedures are imperative. Apart from these indications, the clinical benefits of revascularisation have not yet been demonstrated. In all cases, the control of associated risk factors is essential to maintain the success of revascularisation and slow down the progression of atheromatous disease.

[Renovaascular hypertension and Von Recklinghausen neurofibromatosis]. / Hypertension rénovasculaire et neurofibromatose de Von Recklinghausen.

This clinical case illustrates the diagnosis of a secondary cause of hypertension in a patient with Von Recklinghausen's disease. The hypertension resulted from a complex malformation of the right renal artery and dysplasic stenosis of the left inferior polar artery treated successfully by simple angioplasty. This case illustrates the high proportion of vascular (renal artery dysplasia, coarctation of the aorta) and endocrine (pheochromocytoma) causes of hypertension in patients with neurofibromatosis.

[Method of studying renal morphology in hypertensive patients with and without renal artery stenosis]. / Méthode d'étude de la morphologie rénale chez le patient hypertendu avec et sans sténose de l'artère rénale.

UNLABELLED: Although the size of the kidney is still the most commonly used as morphological parameter, it is not enough sensitive for early detection of ischemic nephropathy. PURPOSE: To study a novel method of renal morphology analysis using spiral computed tomography angiography (CTA) in hypertensive patients with or without unilateral atheromatous renal artery stenosis (RAS). METHODS: Forty-nine hypertensive patients suspected RAS underwent spiral CTA. Arteriography showed significant RAS in 26 patients. Renal length, 3 upper and 3 lower cortical thicknesses were measured in 46 control kidneys (C) i.e. 23 patients without RAS (group 1), in 26 stenosed (S) and in 26 opposite kidneys (OPP) i.e. 26 patients with unilateral RAS (group 2). Mean cortical thickness (MCT), cortical area (CA), medullary length (ML) were calculated in the same groups. The reproducibility and agreement of measurements were investigated in two groups. The demographic parameters (age, sex, bodymass index, and history of hypertension) were correlated with morphological parameters in group 1. RESULTS: The reproducibility and agreement of measurements were confirmed (R2 = 0.53 to 0.93) except for anterosuperior thickness. The C kidneys were of comparable morphology: MCT (mm) = 9.1 +/- 0.6; 9.2 +/- 1.0, CA (mm2) = 950 +/- 119; 934 +/- 157, ML (mm) = 85 +/- 11. In group of Opp kidneys, MCT = 7.9 +/- 1.4 mm, CA = 806 +/- 210 mm2, ML = 84 +/- 13 mm. In group of S kidneys, MCT = 6.6 +/- 1.6 mm, CA = 612 +/- 193 mm2, ML = 77 +/- 14 mm. Demographic parameters were not correlated to renal morphology. CONCLUSION: Spiral CTA is a suitable method to study renal morphology. Cortical thickness and medullary length could be used to obtain a reliable diagnosis of early ischemic nephropathy.

[Important of magnetic resonance angiography with gadolinium injection in pulmonary vein diseases]. / Intérêt de l'angiographie par résonance magnétique avec injection de gadolinium dans le bilan des pathologies des veines pulmonaires.

The study of the pulmonary veins by echocardiography is sometimes difficult especially when the ultrasonic window is restricted. Conventional angiography is the classic reference examination but it exposes the patient to ionising radiation and requires the injection of an iodine contrast product. Another technique that can provide the essential information is magnetic resonance angiography (MRA) with injection of gadolinium. It was performed in 9 patients for suspected congenital or acquired anomalies of the pulmonary veins between June 1999 and December 2001. The patient's ages varied from 1 month to 10 years. The examinations were carried out on a 1.5 T Vision machine (Siemens, Erlangen, Germany) without "cardiac gating" or apnoea after parental consent. MRA with gadolinium injection showed 5 drainage anomalies (3 partial pulmonary venous refluxes in the superior vena cava, 2 scimitar syndromes) and 3 stenoses (one due to compression by an aneurysm of the left pulmonary artery, a second secondary to pericardial agenesis, and a third secondary to hypoplasia of an isolated vein). MRA allowed three dimensional visualisation of these anomalies. This is a rapid, non-invasive and certain imaging technique which does not expose the patient to ionising radiation. It is therefore of significance in the investigation of anomalies of the pulmonary veins complementing echocardiography, and could in future replace cardiac catheterisation.

[Intravascular Doppler for the evaluation of renal blood flow: validation and demonstration of vessel reactivity]. / Doppler endovasculaire dans les artères rénales. Validation de la méthode et mise en évidence de la réactivité vasculaire.

AIM: To assess the feasibility and to demonstrate the potential clinical application of intravascular doppler in the evaluation of renal blood flow in patients with hypertension and normal renal arteries. MATERIALS AND METHODS: Intravascular doppler was used to measure renal blood flow in 19 patients (34 kidneys) during arteriography to rule out renovascular hypertension. Arteriography showed no evidence of renal artery stenosis in any patient. Hemodynamic parameters, renal artery diameter, and doppler measurements were undertaken at baseline, after injection of a bolus (10 ml) of normal (0.9%) saline, and after injection of isosorbide dinitrate (1 mg diluted in 10 ml normal saline). RESULTS: Repeated measurements of renal blood flow confirmed the reproducibility of the technique. Basal blood flow was similar in both right and left kidneys; injection of vehicle solution (10 ml normal saline) had no effect on doppler parameters. Injection of isosorbide dinitrate resulted in a significant increase in renal blood flow velocity reflecting an increase in renal blood flow; this demonstrates the existence of a renal flow reserve. The degree of increase in renal blood flow varied significantly between kidneys. CONCLUSIONS: Intravascular doppler is a safe, effective, and reproducible technique for measurement of renal blood flow. It allows evaluation of variations in renal blood flow in response to diverse vasoactive drugs or other vasomotor stimuli. The present study demonstrated the heterogenous response of renal blood flow in response to vasodilator stimuli.

[Imaging of the renal arteries: when, how and why?]. / Quand, comment et pourquoi réaliser une exploration des artères rénales?

The objectives of this course are both: to describe acquisition, injection and reconstruction parameters of volumic images for renal arteries examination and specific signs; to discuss the role of the different images in the diagnosis and in the therapeutic management. Ultrasound is one of the best imaging for the analysis of renal arteries in the detection of stenosis even if the sensitivity is less (around 85%)compared to CT Angiography (95%) and MR Angiography (90%). Because of this advantage and of 3D evaluation, CTA and MRA are sometimes in the first line for renal artery evaluation and can assess morphology before angioplasty. Renal scintigraphy with Captopril test and renin dosage are only used for small kidney evaluation. Arteriogram is systematically followed by angioplasty if possible. With the new endovascular materials, complications decrease (less than 5% with a major reduction in cholesterol emboli) and indications of endoprosthesis increase (71% of stenting with half of it in direct stenting technique). This course will give practical tools for imaging acquisition, specifically 3D imaging, for indications and management of lesion in accordance to symptoms and morphology.