Predictors of mitral annulus enlargement? A real-time three-dimensional transesophageal study.

BACKGROUND: Mitral annulus (MA) enlargement can be observed in various cardiac conditions but respective influence of left atrial (LA) and left ventricle (LV) size remained unclear. METHODS: In 120 patients who underwent a clinically indicated 3D-transesophageal-echocardiography, 30 atrial fibrillation (AF), 30 secondary mitral regurgitation (SMR), 30 primary myxomatous mitral regurgitation (PMR) and 30 mitral stenosis (MS), we evaluated the association between MA area (MA-area) and LA volume (LAvol) measured using the biplane area-length method, end-diastolic (LVEDV) and end-systolic (LVESV) volumes measured using the biplane Simpson method. MA-area was measured based on 3D datasets using QLab10. RESULTS: MA-area was correlated to LVEDV (r = 0.42, p < 0.0001), LVESV (r = 0.29, p = 0.001) but more markedly to LAvol (r = 0.62, p < 0.0001). Correlation between MA-area and LAvol was sustained in all subsets whereas MA-area was not correlated to LVEDV and LVESV in patients with SMR and with PMR (all p > 0.10). In multivariate analysis main predictors of MA-area were LAvol (p < 0.0001) and myxomatous etiology of MR (p = 0.0003) followed by LVEDV (p = 0.006) and LVESV (p = 0.02). CONCLUSION: In a population of patients with a wide range of LA/LV size related to various conditions, LA volume and myxomatous MR etiology appeared as main predictors of MA size whereas LV size had a more modest influence.

Eclipsed mitral regurgitation: an unusual cause of acute heart failure.

AIMS: So far, a total of five patients with eclipsed mitral regurgitation (MR) have been reported in the literature by three different teams. The aim of this article was to detail clinical and echocardiographic characteristics, and outcome of patients presenting eclipsed MR. METHODS AND RESULTS: We defined eclipsed MR as spontaneous appearance, at rest, from 1 min to the next of an acute restriction in the motion of mitral leaflets preventing coaptation and leading to massive MR in patients with normal left ventricular end-diastolic diameter, left ventricular ejection fraction >45%, and baseline MR ≤2. Spontaneous regression occurred within 30 min, and no obvious trigger such as acute hypertension, new-onset arrhythmia, or myocardial ischaemia is present. Clinical data, ECG, echocardiographic data, surgery report, and follow-up status of six patients with eclipsed MR are reported: all were post-menopausal women with median age of 74 [57-80] years presenting hypertension (4/6), chronic kidney disease (5/6), or chronic anaemia (4/6). Five out of six patients experienced acute pulmonary oedema requiring hospitalization and underwent mitral valve replacement because of heart failure recurrence. Two patients died in the first days after surgery while the three others are free of symptoms at, respectively, 56, 18, and 10 months follow-up. CONCLUSION: Eclipsed MR is a clinical and echocardiographic syndrome responsible for heart failure with preserved EF. It is presently underdiagnosed and should be evoked in cases of recurrent acute pulmonary oedema without obvious trigger, in particular in patients presenting discordant evaluation of MR severity over time.

Mitral endocarditis due to Rothia aeria with cerebral haemorrhage and femoral mycotic aneurysms, first French description.

Rothia aeria is a Rothia species from the Micrococcaceae family. We report here the first French R. aeria endocarditis complicated by brain haemorrhage and femoral mycotic aneurysms. Altogether, severity and antimicrobial susceptibility should make us consider the management of R. aeria endocarditis as Staphylococcus aureus methicillin-susceptible endocarditis.

Infective endocarditis with symptomatic cerebral complications: contribution of cerebral magnetic resonance imaging.

BACKGROUND: Cerebral complications are well-identified causes of morbidity and mortality in patients with infective endocarditis (IE). Few studies have analysed the impact of brain magnetic resonance imaging (MRI) in IE patients with neurological manifestations. OBJECTIVES: The aims of this study were to assess the MRI contribution to the management of patients with IE neurological manifestations and to compare cerebral CT and MRI findings. MATERIAL AND METHODS: Patients with definite or probable IE and neurological manifestations were prospectively enrolled from 2005 to 2008, in a university hospital (Bichat Claude Bernard Hospital, Paris). Clinical and radiological characteristics and echocardiographic findings were systematically recorded. Brain MRI with angiography was performed and compared to available CT scans. The contribution of MRI results to cerebral involvement staging and to therapeutic plans was evaluated. RESULTS: Thirty patients, 37-89 years old, were included. Nineteen suffered from pre-existing heart disease. Blood cultures were positive in 29 cases and the main micro-organisms were streptococci (n = 14) and staphylococci (n = 13). The IE was mainly located on mitral (n = 15) and aortic valves (n = 13). Neurological events were strokes (n = 12), meningitis (n = 5), seizures (n = 1), impaired consciousness (n = 11) and severe headache (n = 1). MRI findings included ischaemic lesions (n = 25), haemorrhagic lesions (n = 2), subarachnoid haemorrhage (n = 5), brain abscess (n = 6), mycotic aneurysm (n = 7), vascular occlusion (n = 3) and cerebral microbleeds (n = 17). In 19/30 cases, neurological manifestations were observed before the diagnosis of IE. MRI was more sensitive than CT scan in detecting both clinically symptomatic cerebral lesions (100 and 81%, respectively) and additional asymptomatic lesions (50 and 23%, respectively). Therapeutic plans were modified according to MRI results in 27% of patients: antibiotherapy regimen modifications in 7% (switch for molecules with high cerebral diffusion) and surgical plan modifications in 20% (indication of valvular replacement due to the embolic nature of the vegetations revealed by MRI or postponement of surgery due to haemorrhagic lesions). None of the 16/30 (51%) operated-on patients experienced postoperative neurological worsening. In-hospital death occurred in 4 patients. CONCLUSION: In patients with IE neurological manifestations, MRI revealed a broader involvement of the brain (type and number of lesions) than indicated by clinical signs and/or CT scan. With a better disease staging of neurological manifestations, MRI brain imaging may help in patient management and the decision-making process especially for cardiac surgery indication and timing of valve replacement.

[Cardiac diffusion MRI of recent and chronic myocardial infarction: preliminary results]. / IRM de diffusion cardiaque dans l'infarctus du myocarde récent et chronique: expérience préliminaire.

PURPOSE: To use diffusion weighted MR imaging (DWI), a technique routinely used in patients with stroke, for diagnosis of myocardial infarction (MI). MATERIALS AND METHODS: A breath hold ECG gated DWI sequence (b = 300 sec/mm2) was developped and applied to 7 patients with recent MI (3-15 days), 3 patients with chronic MI (> 6 months) and 4 patients with valvular heart disease without MI (control cases). DWI data were correlated to T2W, first pass perfusion and delayed enhancement data. RESULTS: In all patients with recent MI, DWI showed an area of increased signal with reduction of ADC relative to normal myocardium. Hyperintense lesion on DWI corresponded to areas of delayed enhancement. The diffusion images were normal in patients with chronic MI or no MI. CONCLUSION: Even though no animal model or other reference method is available, these preliminary results indicate that DWI could assist clinicians in detecting recent MI.

An unusual cause of pacemaker-induced severe tricuspid regurgitation.

Pacemaker (PM) induced tricuspid regurgitation (TR) is a common echocardiographic finding. Although mild or moderate TR is frequently observed, severe TR is rare. We report the exceptional observation of a severe TR due to leaflet malcoaptation occurring late after PM implantation and in the following weeks after an aortic valve replacement. Our hypothesis is that the aortic valve surgery has been responsible for conformational changes between cardiac cavities, tricuspid valve and PM leads resulting in a severe TR.

[Echocardiography in the catheterization unit]. / L'échocardiographie en salle de cathétérisme.

Non-coronary interventional cardiology has for about ten years been undergoing significant development, with the arrival of new percutaneous procedures in various domains. Some of them have already been well validated, notably percutaneous mitral comissurotomy, percutaneous closure of inter-atrial (IA) communications and patent foramen ovale, trans-septal catheterisation, and alcohol septal ablation of hypertrophic obstructive cardiomyopathy. Other interventional techniques are still in the validation phase, such as the techniques for percutaneous occlusion of the left atrium, percutaneous implantation of valvular prostheses, or the new approaches to percutaneous treatment of mitral valvulopathy. The rapid development of these techniques has benefited widely from the use of echocardiography in the catheter suite, providing a very precise clarification of the anatomy and continuous guidance during procedures. This echocardiographic guidance provides optimal results for the interventional procedure and reduces the incidence of complications.

[Recommendations for noncardiac surgery in aortic stenosis]. / Rétrécissement aortique et chirurgie extracardiaque: quelques recommandations.

Aortic stenosis (AS) is the most common valve disease in western countries and its prevalence increases with population aging. AS is an important risk factor for perioperative complications in patients undergoing noncardiac surgery, a common situation in older patients. Preoperative evaluation should be based on a careful cardiac and general examination (risk factors and comorbidities) as well as on the type and urgency of the noncardiac surgery (urgent as opposed to elective). Careful teamwork and communication between the cardiologist, the anesthesiologist and the surgeon is mandatory. It is also critical that the anesthesiologist team is used to managing these high-risk patients. In cases of non-severe AS (>0.6 cm2/m2 of body surface area), the noncardiac surgery can be performed first. If AS is severe (< or =0.6 cm2/m2) and the noncardiac surgery elective, it is appropriate to consider an aortic valve replacement first. In the difficult cases of urgent noncardiac surgery in patients with severe AS, which precludes heart surgery, it is possible either to first proceed with the noncardiac surgery under very careful anesthesiologic management or to perform the percutaneous aortic valve commissurotomy first.

[Determinants and prognosis of ischemic mitral regurgitation]. / Insuffisances mitrales ischémiques: mécanisme et pronostic.

Ischemic mitral regurgitation (IMR) is mitral regurgitation (MR) due to complications of coronary artery disease. Two mechanisms can be individualized. Acute MR secondary to ruptured papillary muscle is a rare but often fatal complication of myocardial infarction. We focus on functional MR, much more common, which occurs without any intrinsic valve disease. It was often underrated because of low murmur intensity but is observed between 15 and 20% after a myocardial infarction. The presence and degree of the regurgitation are related to local left ventricular remodeling. The apical and posterior displacement of papillary muscles leads to excess valvular tenting which in turn, in association with loss of systolic annular contraction, determines the severity of the regurgitation. IMR presence is associated with an excess mortality. The mortality risk is directly related to the degree of the regurgitation and a regurgitant volume > or = 30 ml or an effective regurgitant orifice > or = 20 mm2 define a high-risk group. In current clinical practice, IMR is mainly corrected with ring annuloplasty. However, this technique does not correct local alterations of left ventricular remodeling and its benefits on long-term outcome remains to be demonstrated.

[An exceptional etiology of left ventricular aneurysm: type AA amyloidosis]. / Une cause exceptionnelle d'anévrisme du ventricule gauche: l'amylose de type AA.

Left ventricular aneurysms most often occur in the course of myocardial infarction. In rare cases they can be detected when the coronary network is devoid of any lesions. The aetiology is therefore multiple and dependent on the context. One aetiology seems less exceptional and concerns idiopathic aneurysms encountered in the African population, where the role of a "debilitating condition" such as tuberculosis has been evoked. We report the case history of a young patient from Zaire with a left ventricular aneurysm discovered in association with ganglionic tuberculosis complicated by AA amyloidosis. Histological analysis allowed the aetiological diagnosis to be established. Aneurysmal dilatation of the left ventricle was reported in the presence of amyloid deposits at the intra-myocardial arteriole level, whereas the context suggested a tubercular role. In spite of the difficulty of establishing a precise aetiological diagnosis, there seems to exist a consensus for surgical management.

Potentiation of urinary atrial natriuretic peptide interferes with macula densa function.

OBJECTIVES: Neutral endopeptidase (NEP) inhibition potentiated the renal action of Atrial Natriuretic Peptide (ANP) and was associated with appearance of the peptide in the urine, providing evidence of protection of the filtrated peptide along the course of the nephron. The macula densa, composed of epithelial cells, receives ionic information from the urinary compartment via Na-K-2Cl cotransport and influences renin secretion by the myoepithelioïd cells in the afferent arteriole. bNOS constitutively expressed in the epithelial cells of the macula densa is involved in this feed-back. NEP inhibition was associated with the absence of any increase in renin secretion. The hypothesis is that potentiation of urinary ANP by NEP inhibition could limit renin secretion by directly or indirectly targeting the macula densa in vivo. METHODS AND RESULTS: We tested the interaction between NEP inhibition (candoxatril) and Na-K-2Cl inhibition (bumetanide) on electrolyte and ANP urinary excretion, renin secretion, macula densa activity (NADPH diaphorase activity and bNOS mRNA) and TSC-1 mRNA expression in the renal cortex and BSC-1 in the renal medulla of rats treated for 5 days. Bumetanide increased urinary electrolyte excretion whereas candoxatril did not. Candoxatril increased urinary ANP and cyclic GMP excretion. Bumetanide increased renin and aldosterone secretion whereas candoxatril decreased renin secretion. This effect on renin release was associated with an increase in macula densa NADPH diaphorase activity in the bumetanide-treated group which was blunted by candoxatril. Lastly, bumetanide increased TSC-1 mRNA expression in the cortex and this effect was blunted by candoxatril. CONCLUSION: These results suggest that potentiation of ANP by NEP inhibition could interfere with tubular function at different levels and limit renin secretion by a urinary pathway involving macula densa activity.

Shear stress induces iNOS expression in cultured smooth muscle cells: role of oxidative stress.

After deendothelialization, the most luminal smooth muscle cells of the neointima are in contact with blood flow and express inducible nitric oxide synthase (iNOS) in vivo. We hypothesized that shear stress may be a stimulus for this iNOS overexpression. We have thus submitted smooth muscle cells to laminar shear and measured the iNOS expression. Shear stress (20 dyn/cm(2)) induced iNOS mRNA and protein expression, whereas brain NOS mRNA expression was decreased. Conversely, nitrite production was increased. This production was blocked by a selective iNOS inhibitor. Pyrrolidine dithiocarbamate, an antioxidant molecule, and BXT-51072, a gluthation peroxidase mimic, both inhibited the shear-induced iNOS expression. Shear stress also increased the expression of both membrane subunits of NADPH oxidase p22(phox) and Mox-1. Shear stress activated the redox-sensitive nuclear translocation of the transcription nuclear factor-kappaB (NF-kappaB) and stimulated the degradation of both cytosolic inhibitors kappaB alpha and beta. These results show that shear stress can induce iNOS expression and nitrite production in smooth muscle cells and suggest that this regulation is probably mediated by oxidative stress-induced NF-kappaB activation.

Molecular plasticity of vascular wall during N(G)-nitro-L-arginine methyl ester-induced hypertension: modulation of proinflammatory signals.

It has previously been reported that hypertension induced by the chronic blockade of NO production is characterized by a proinflammatory phenotype of the arterial wall associated with a periarterial accumulation of inflammatory cells. In the present study, the cellular and molecular mechanisms involved in the luminal and perivascular accumulation of inflammatory cells were evaluated in the aortas of N(G)-nitro-L-arginine methyl ester (L-NAME)-treated rats. Because the medial layer remains intact, putative markers of the resistance of the vascular wall to cell migration and to oxidative stress were also explored. For this purpose, monocyte adhesion, cytokine expression, superoxide anion production, and nuclear factor-kappa B (NF-kappa B) activation were assessed in the aortas of L-NAME-treated rats. Expressions of tissue inhibitor of metalloproteinases-1 (TIMP-1) and heme oxygenase-1 (HO-1) in the aortic wall were also studied as possible markers of such resistance. Chronic blockade of NO production increased ex vivo monocyte adhesion to the endothelium, increased the production of superoxide anions, and activated the NF-kappa B system. In concert with this modification of the redox state of the vascular wall in L-NAME-treated rats, the expression of proinflammatory cytokines interleukin-6, monocyte chemoattractant protein-1, and macrophage colony-stimulating factor was increased. In parallel, expressions of both TIMP-1 and HO-1 were increased. All these changes were prevented by treatment with an angiotensin-converting enzyme inhibitor (Zofenopril). Hypertension associated with a proinflammatory phenotype of the vascular wall induced by blockade of NO production could be due to an increase in oxidative stress, which, in turn, activates the NF-kappa B system and increases gene expression. In parallel, the arterial wall overexpresses factors such as TIMP-1 and HO-1, which could participate in the resistance to cell migration and oxidative stress.

[The best of valvular heart disease in 1999]. / L'essentiel de 1999 dans les valvulopathies.

The year 1999 confirmed important changes in the clinical presentation, the methods of investigation and the treatment of valvular heart disease. The near disappearance of acute rheumatic fever in the developed world, associated with the increase in life expectancy has resulted in degenerative aetiologies becoming the most common causes of valvular heart disease with a dominance of aortic stenosis and mitral incompetence. The increase in average age of the operated patients explains the increasing role of comorbidity and the higher incidence of mixed (valvular and coronary artery) surgery. Doppler echocardiography is now the reference method of investigating valvular heart disease, both pre- and post-operatively (especially in mitral incompetence). The value of tri-dimensional echocardiography is beginning to be recognised. The technical advances in surgical techniques are also important, especially the extension of conservative methods both in mitral incompetence and parietal lesions of dystrophic aortic incompetence. The good long-term results of homograft aortic valves have been confirmed, especially in young patients and infectious endocarditis complicated by abscess. The Ross procedure is an interesting alternative in children and adolescents in the absence of available homografts. The persistence of good results in the long term has made percutaneous mitral commissurotomy the reference in mitral stenosis. The improvement in surgical and interventional methods has widened the operative indications which are now considered in patients who are pauci- or a-symptomatic.