Mitral Valve Surgery for Rheumatic Lesions in Young Patients

BACKGROUND: The appropriateness of rheumatic mitral valve repair remains controversial due to the risks of recurrent mitral dysfunction and need for reoperation. The aims of this study were to determine the overall short- and long-term outcomes of pediatric rheumatic mitral valve surgery in our center. METHODS: Single-center, observational, retrospective study that analyzed the results of rheumatic mitral valve surgery in young patients, consecutively operated by the same team, between 1999 and 2014. RESULTS: We included 116 patients (mean age = 12.6 ± 3.5 years), of which 66 (57%) were females. A total of 116 primary surgical interventions and 22 reoperations were performed. Primary valve repair was possible in 86 (74%) patients and valve replacement occurred in 30 (26%). Sixty percent of the patients were followed up beyond three months after surgery (median follow-up time = 9.2 months [minimum = 10 days; maximum = 15 years]). Long-term clinical outcomes were favorable, with most patients in New York Heart Association functional class I (89.6%) and in sinus rhythm (85%). Freedom from reoperation for primary valve repair at six months, five years, and ten years was 96.4% ± 0.25%, 72% ± 0.72%, and 44.7% ± 1.34%, respectively. Freedom from reoperation for primary valve replacement at six months, five years, and ten years was 100%, 91.7% ± 0.86%, and 91.7% ± 0.86%, respectively. Mitral stenosis as the primary lesion dictated early reintervention. CONCLUSIONS: Despite the greater rate of reoperation, especially when the primary lesion was mitral stenosis, rheumatic mitral valve repair provides similar clinical outcomes as compared with replacement, with the advantage of avoiding anticoagulation.

Myocardial Extracellular Volume Expansion And The Risk Of Recurrent Atrial Fibrillation After Pulmonary Vein Isolation.

This study tested whether myocardial extracellular volume (ECV) is increased in patients with hypertension and atrial fibrillation (AF) undergoing pulmonary vein isolation and whether there is an association between ECV and post-procedural recurrence of AF. Hypertension is associated with myocardial fibrosis, an increase in ECV, and AF. Data linking these findings are limited. T1 measurements pre-contrast and post-contrast in a cardiac magnetic resonance (CMR) study provide a method for quantification of ECV. Consecutive patients with hypertension and recurrent AF referred for pulmonary vein isolation underwent a contrast CMR study with measurement of ECV and were followed up prospectively for a median of 18 months. The endpoint of interest was late recurrence of AF. Patients had elevated left ventricular (LV) volumes, LV mass, left atrial volumes, and increased ECV (patients with AF, 0.34 ± 0.03; healthy control patients, 0.29 ± 0.03; p < 0.001). There were positive associations between ECV and left atrial volume (r = 0.46, p < 0.01) and LV mass and a negative association between ECV and diastolic function (early mitral annular relaxation [E'], r = -0.55, p < 0.001). In the best overall multivariable model, ECV was the strongest predictor of the primary outcome of recurrent AF (hazard ratio: 1.29; 95% confidence interval: 1.15 to 1.44; p < 0.0001) and the secondary composite outcome of recurrent AF, heart failure admission, and death (hazard ratio: 1.35; 95% confidence interval: 1.21 to 1.51; p < 0.0001). Each 10% increase in ECV was associated with a 29% increased risk of recurrent AF. In patients with AF and hypertension, expansion of ECV is associated with diastolic function and left atrial remodeling and is a strong independent predictor of recurrent AF post-pulmonary vein isolation.

Doença periodontal em portadoras de valvopatia durante a gravidez: estudo clínico e microbiológico

FUNDAMENTO: A doença periodontal representa risco à gestante portadora de valvopatia reumática, seja para contrair endocardite infecciosa, seja por propiciar complicações obstétricas. OBJETIVO: Estudar a frequência da doença periodontal em portadoras de valvopatia reumática durante a gravidez. MÉTODOS: Foram estudadas 140 gestantes, comparáveis quanto a idade e o nível socioeconômico, divididas em: 70 portadoras de doença valvar reumática e 70 mulheres saudáveis. Todas se submeteram a: 1) avaliação clínica odontológica que incluiu a análise dos seguintes parâmetros: 1.1) profundidade à sondagem, 1.2) distância da linha esmalte-cemento à margem gengival, 1.3) nível clínico de inserção, 1.4) índice de sangramento, 1.5) índice de placa bacteriana, e, 1.6) comprometimento de furca; e, 2) exame microbiológico nas amostras de saliva e do cone que considerou o controle positivo para as cepas das bactérias Porphyromonas gingivalis, Tannerella forsithia e Aggregobacter actinomycetemcomitans. RESULTADOS: A lesão valvar mitral foi prevalente (65 casos = 92,8%) dentre as gestantes cardiopatas. A comparação entre os grupos mostrou não haver diferenças entre idade e a paridade, e embora tenham sido verificadas diferenças entre as medidas da distância da linha esmalte-cemento à margem gengival (p = 0,01) e o índice de placa (p=0,04), a frequência da doença periodontal identificada em 20 (14,3%) gestantes, não foi diferente entre os grupos (p = 0,147). O exame microbiológico mostrou uma proporção maior da bactéria P. gingivalis na saliva de gestantes saudáveis (p = 0,004). CONCLUSÃO: O estudo clínico e microbiológico periodontal durante a gravidez demonstrou igual frequência da doença periodontal em portadoras de valvopatia reumática quando comparada às mulheres saudáveis.

Infectious endocarditis caused by Nocardia sp.: histological morphology as a guide for the specific diagnosis

Nocardia is a rare opportunistic agent, which may affect immunocompromised individuals causing lung infections and exceptionally infective endocarditis (IE). There are few reports of IE caused by Nocardia sp., usually involving biological prostheses but rarely in natural valves. Its accurate microbiological identification may be hampered by the similarity with Rhodococcus equi and Corynebacterium spp. Here we report a case of native mitral valve IE caused by this agent in which the clinical absence of response to vancomycin and the suggestion of Nocardia sp. by histology pointed to the misdiagnosis of Corynebacterium spp. in blood cultures. The histological morphology can advise on the need for expansion of cultivation time and use of extra microbiological procedures that lead to the differential diagnosis with Corynebacterium spp. and other agents, which is essential to establish timely specific treatment, especially in immunocompromised patients.

Study of the cardiac left atrioventricular valvar complex in water buffaloes (Bubalus bubalis) of the Jafarabadi breed

Atrioventricular valve complex of 30 Jafarabadi water buffaloes, adult males were studied in this research with no heart diseases. The animals were obtained from a slaughterhouse in Brazilian State of Parana. The hearts were opened at the third portion affording access to the valve complex. The complexes had its area, number and type of tendinous cords submitted to analysis. The results showed that the complex is composed by two cusps and four accessory cusps, two or three papillary muscles in which 10-25 tendinous cords fix on the cusps that face the ventricle wall. The total area of the complex was on average 38.56cm², with a minimum of 24.96cm² and a maximum of 55.54cm². Statistically, no relation between the number of cords and the cusps' area where they are inserted or with the number of papillary muscle where they originated from was observed.

Echocardiographic study of paediatric patients with mucopolysaccharidosis

Principle Mucopolysaccharidosis is an inborn error of metabolism causing glucosaminoglycans tissue storage. Cardiovascular involvement is variable but contributes significantly towards the morbidity and mortality of the patients. Objective To characterise the echocardiographic abnormalities in children and adolescents with different types of mucopolysaccharidosis. Method Echocardiograms and medical records of 28 patients aged 2–14 years, seen from 2003 to 2005, were revised. At that time, the enzymatic replacement therapy was still not available in our institution.Results Echocardiographic alterations were detected in 26 patients (93 per cent), whereas 16 (57 per cent) had abnormal auscultation, and only 6 (21 per cent) presented with cardiovascular complaint. Mitral valve thickening with dysfunction (regurgitation, stenosis, or double lesion) was diagnosed in 60.8 per cent, left ventricular hypertrophy in 43 per cent and aortic valve thickening with regurgitation in 35.8 per cent of the patients. There was no systolic dysfunction and mild left diastolic dysfunction was shown in 21.5 per cent of the patients. Pulmonary hypertension was present in 36 per cent of the patients, causing the only two deaths recorded. There was a strong association between the accumulation of dermatan sulphate and the presence of mitral valve dysfunction (p = 0.0003), aortic valve dysfunction (p = 0.006), and pulmonary hypertension (p = 0.006). Among individuals with two or more examinations, 82 per cent had a worsening evolution. Conclusions Echocardiographic alterations in children with Mucopolysaccharidosis are frequent and have a progressive character Left valve lesions, ventricular hypertrophy, and pulmonary hypertension were the most common findings and there was an association between the accumulation of dermatan sulphate and cardiovascular involvement. Unlike in adults, pulmonary hypertension was the main cause of death, not left ventricle systolic dysfunction

Errors in lamina growth of primary olfactory axons in the rat and mouse olfactory bulb

In the adult olfactory nerve pathway of rodents, each primary olfactory axon forms a terminal arbor in a single glomerulus in the olfactory bulb. During development, axons are believed to project directly to and terminate precisely within a glomerulus without any exuberant growth or mistargeting. To gain insight into mechanisms underlying this process, the trajectories of primary olfactory axons during glomerular formation were studied in the neonatal period. Histochemical staining of mouse olfactory bulb sections with the lectin Dolichos biflorus-agglutinin revealed that many olfactory axons overshoot the glomerular layer and course into the deeper laminae of the bulb in the early postnatal period. Single primary olfactory axons were anterogradely labelled either with the lipophilic carbocyanine dye, 1,1'-dioctodecyl-3,3,3',3'-tetramethylindocarbocyanine perchlorate (DiI), or with horseradish peroxidase (HRP) by localized microinjections into the nerve fiber layer of the rat olfactory bulb. Five distinct trajectories of primary olfactory axons were observed in DLI-labelled preparations at postnatal day 1.5 (P1.5). Axons either coursed directly to and terminated specifically within a glomerulus, branched before terminating in a glomerulus, bypassed glomeruli and entered the underlying external plexiform layer, passed through the glomerular layer with side branches into glomeruli, or branched into more than one glomerulus. HRP-labelled axon arbors from eight postnatal ages were reconstructed by camera lucida and were used to determine arbor length, arbor area, and arbor branch number. Whereas primary olfactory axons display errors in laminar targeting in the mammalian olfactory bulb, axon arbors typically achieve their adult morphology without exuberant growth. Many olfactory axons appear not to recognize appropriate cues to terminate within the glomerular layer during the early postnatal period. However, primary olfactory axons exhibit precise targeting in the glomerular layer after P5.5, indicating temporal differences in either the presence of guidance cues or the ability of axons to respond to these cues. (C) 1999 Wiley-Liss, Inc.

Expression of EphA5 during development of the olfactory nerve pathway in rat

The olfactory neuroepithelium is a highly plastic region of the nervous system that undergoes continual turnover of primary olfactory neurons throughout life. The mechanisms responsible for persistent growth and guidance of primary olfactory axons along the olfactory nerve are unknown. In the present study, we used antibodies against the Eph-related receptor, EphA5, to localise EphA5, and recombinant EDhA5-IgG fusion protein to localise its ligands. We found that although both EphA5 and its ligands were both expressed by primary olfactory neurons within the embryonic olfactory nerve pathway, there was no graded or complementary expression pattern. In contrast, the expression patterns altered postnatally such that primary olfactory neurons expressed the ligands, whereas the second-order olfactory neurons, the mitral cells, expressed EphA5. The role of EphA5 was analysed by blocking EphA5-ligand interactions in explant cultures of olfactory neuroepithelium using anti-EphA5 antibodies and recombinant EphA5. These perturbations reduced neurite outgrowth from explant cultures and suggest that intrafascicular axon repulsion may serve to limit adhesion and optimise conditions for axon growth. (C) 2000 Wiley-Liss, Inc.

Endomyocardial Biopsy as Risk Factor in the Development of Tricuspid Insufficiency After Heart Transplantation

Objective. Endomyocardial biopsy (EMB), which is used to monitor for rejection, may cause tricuspid regurgitation (TR) after orthotopic heart transplantation (OHT). The purpose of this investigation was to examine the occurrence of tricuspid valve tissue in myocardial specimens obtained by routine EMB performed after OHT. Patients and Methods. From January 2000 to July 2008, 125 of the patients who underwent OHT survived more than I month. Their follow-up varied from I month to 8.5 years (mean, 5.1 +/- 3.7 years). EMB was the gold standard examination and myocardial scintigraphy with gallium served as a screen to routinely monitor rejection. Results. Each of 428 EMB including 4 to 7 fragments, totaling 1715 fragments, were reviewed for this study. The number of EMB per patient varied from 3 to 8 (mean, 4.6 +/- 3.5). Histopathological analysis of these fragments showed tricuspid tissue in 4 patients (3.2%), among whom only I showed aggravation of TR. Conclusions. EMB remains the standard method to diagnose rejection after OLT. It can be performed with low risk. Reducing the number of EMB using gallium myocardial scintigraphy or other alternative methods as well as adoption of special care during the biopsy can significantly minimize trauma to the tricuspid valve.

Heart Transplantation in Arrhythmogenic Right Ventricular Dysplasia: Case Reports

Objective. Arrhythmogenic right ventricular dysplasia (ARVD) is a myocardial disease of familiar, origin where the myocardium is replaced by fibrofatty tissue predominantly in the right ventricle. Herein we have presented the clinical courses of 4 patients with ARVD who underwent orthotopic heart transplantation. Patients and Methods. Among 358 adult patients undergoing heart transplantation, 4 (1.1%) displayed ARVD. The main indication for transplantation was the progression to heart failure associated with arrhythmias. All 4 patients displayed rapid, severe courses leading to heart failure with left ventricular involvement and uncontrolled arrhythmias. Results. In all cases the transplantation was performed using a bicaval technique with prophylactic tricuspid valve annuloplasty. One patient developed hyperacute rejection and infection, leading to death on the 7th day after surgery. The other 3 cases showed a good evolution with clinical remission of the symptoms. Pathological study of the explanted hearts confirmed the presence of the disease. Conclusions. ARVD is a serious cardiomyopathy that can develop malignant arrhythmias, severe ventricular dysfunction with right ventricular predominance, and sudden cardiac death. Orthotopic heart transplantation must always be considered in advanced cases of ARVD with malignant arrhythmias or refractory congestive heart failure with or without uncontrolled arrhythmias, because it is the only way to remit the symptoms and the disease.

Left Atrial Function After Ablation for Paroxysmal Atrial Fibrillation

Radiofirequency ablation of the pulmonary veins has been used to treat patients with paroxysmal atrial fibrillation (AF), and atrial damage after ablation is an issue of concern. To evaluate left atrial function shortly and midterm after ablation, 33 consecutive patients with paroxysmal AF were studied at baseline, 24 hours, and >= 6 months after ablation. Patients in sinus rhythm with normal ventricular function were included in the study. Echocardiographic measurements of left atrial volumes (Simpson`s rule) and transmitral and tissue Doppler myocardial (A`) velocities at the septal and lateral mitral annulus were undertaken at each time. Left atrial emptying fraction (EF; maximal - minimal left atrial volume/maximal left atrial volume) was used to express left atrial function. After 8 +/- 2 months, 30 of 33 patients returned (23 men, age 53 +/- 13 years), and all except 2 were in sinus rhythm. Shortly after ablation, left atrial minimal volumes increased (from 30 +/- 15 to 35 +/- 15 ml; p = 0.02), with maximal volumes unchanged, resulting in decreased left atrial EF (from 47 +/- 8 to 40 +/- 7 ml; p <0.05). Tissue Doppler septal A` velocities also decreased (from 8.2 +/- 1.8 to 6.9 +/- 2.0 cm/s; p <0.05). However, after midterm follow-up, both left atrial EF and septal A` velocities had slightly increased compared with shortly after ablation, although left atrial volumes remained similar to baseline. Septal A` velocity changes paralleled left atrial EF both shortly (r = 0.46, p = 0.02) and at midterm after ablation (r = 0.47, p = 0.01). In conclusion, after radiofrequency ablation, patients with paroxysmal AF experienced an initial impairment in atrial function, with improvement at longer term follow-up. (C) 2009 Elsevier Inc. All rights reserved. (Am J Cardiol 2009;103: 395-398)

Characterization of blood-filled cyst by contrast echocardiography and computed tomography

Contrast echocardiography has been demonstrated useful for left ventricular opacification and improvement of endocardial border delineation. Another important clinical application of this technique refers to the better characterization of cardiac tumors and masses. We here described an asymptomatic patient with cystic mass attached to submitral valve apparatus in which contrast echocardiography was performed after intravenous injection of lipid-encapsulated microbubbles. It resulted in enhancement of the cystic borders and allowed for better definition of its diagnosis. Multislice computed tomography confirmed the echocardiographic findings. This case illustrates the potential of contrast echocardiography to improve the anatomic evaluation of cardiac masses.

Atrial Coronary Arteries in Areas Involved in Atrial Fibrillation Catheter Ablation

Background-The proximity to vascular structures is a limiting factor during radiofrequency ablation. However, little or no attention has been given to the atrial arterial circulation during the development of atrial fibrillation (AF) catheter ablation techniques. Methods and Results-We examined the atrial arterial circulation in areas involved in AF ablation in 24 heart specimens by colored resin injection and careful dissection. The sinus node artery (SNA) arose from the circumflex artery in 42% of case; proximal to the LA appendage in 29%, crossing the left atrium (LA) anterior wall; and after the LA appendage in the remaining 13%, crossing the mitral isthmus and passing close to the left pulmonary veins (PVs), the LA roof, and the right superior PV. In 58%, the SNA arose from the right coronary artery. Major arteries (>= 1 mm in external diameter) were found in the mitral isthmus in 54%, at the LA roof in 54%, and at the LA anterior wall in 29%. Around the left PV ostia, there were areas with major arteries in up to 37% (at the roof and inferior segments) and around the right PV ostia in up to 29% (at the roof segment). Conclusions-Major atrial coronary arteries, including the SNA, were commonly found in the areas involved in AF ablation and could cause difficulties in obtaining transmural lesions and electric isolation or even lead to ischemic sinus node or atrial dysfunction. (Circ Arrhythm Electrophysiol. 2010;3:600-605.)