Mitral valve thickening in acute rheumatic fever as a predictor of late valvar dysfunction.

BACKGROUND: Rheumatic heart disease (RHD) complicating acute rheumatic fever (ARF) remains an important health problem in developing countries. No definitive diagnostic test for ARF exists and the role of Doppler echocardiography (DEC) for long-term prognostic evaluation following ARF is not well established. OBJECTIVE: To investigate the prognostic value of DEC in patients with ARF as a predictor of chronic valve dysfunction. METHODS: Prospectively enrolled patients with clinical ARF had a DEC performed soon after diagnosis and repeated at 1, 3, 6 and 12 months and thereafter at every 1-2 years. We defined chronic valve dysfunction by ≥ 3 of the following: increased valve thickening, commissure fusion, subvalvular thickening, reduced leaflet mobility, non-trivial mitral and/or aortic regurgitation. We performed univariate analysis and developed multivariate logistic regression models to identify variables that may influence evolution to RHD. p <0.05 was considered significant. RESULTS: We evaluated 70(57% men) patients, 10.8±5.6 years-old during the ARF episode and followed for 95±26 months. Chronic valve dysfunction was identified in 36(51.4%) which fulfilled criteria for RHD and 10(27.8%) of them died or underwent valve surgery. Univariate analysis showed that mitral valve thickening and presence of mitral regurgitation at baseline DEC, were associated with RHD(p<0.01). Multivariate logistic regression showed that only mitral valve thickness either as a continuous (Odds-Ratio:5.8;95%CI:1.7-19.7) or as a categorical variable (Odds-Ratio:4.04;95%CI:1.06-15.3) was an independent predictor of chronic valve dysfunction. CONCLUSIONS: Mitral leaflets thickening documented at the time of diagnosis of ARF is a consistent prognostic marker for the subsequent evolution to RHD.

Feasibility and reference intervals assessed by conventional and speckle-tracking echocardiography in normal hamsters.

OBJECTIVES: This study aimed to determine feasibility, reference intervals, and reproducibility of left ventricular ejection fraction (LVEF) and speckle-tracking echocardiography (STE) in adult Syrian hamsters. BACKGROUND: Syrian hamster is an experimental model for several heart diseases. Echocardiography allows the evaluation of structure and function with bidimensional conventional techniques and STE. However, there is no data regarding reference values for bidimensional LVEF and myocardial strain in hamsters. METHODS: A total of 135 female Syrian hamsters were anesthetized and studied with a small animal dedicated echocardiography system. Echocardiography measurements were obtained from M-mode and B-mode images. Feasibility and 95% reference intervals were obtained for LVEF using three different approaches: LVEF_Teichholz (from M-mode linear measurements), LVEF_BMode (from area-length method), and LVEF_ STE (from strain), and for global longitudinal (GLS), circumferential (GCS), and radial (GRS) endocardial strain. Reproducibility was assessed as intra-class correlation coefficients. RESULTS: Feasibility of LVEF and endocardial strain was high (95% in FEVE_Teichholz, 93% in the LVEF_BMode, 84% in the LVEF_STE, 84% from PSLAX, and 80% from PSSAX). Values of LVEF_Teichholz were significantly higher than values of LVEF_BMode, and LVEF_STE-derived methods (59.0 ± 5.8, 53.8 ± 4.7, 46.3 ± 5.7, p < 0.0001). The 95% reference intervals for GLS, GCS, and GRS were respectively -13.6(-7.5;-20.4)%, -20.5 ± 3.1%, and + 34,7 ± 7.0%. Intra-class correlation coefficients were 0.49 - 0.91 for LVEF measurements, 0.73 - 0.92 for STE, with better results for LVEF_Teichholz and GLS. CONCLUSIONS: Evaluation of LVEF by several methods and STE parameters is feasible in hamsters. Reference intervals for LVEF and STE obtained for this experimental animal model can be applied at future research.

Clinical Utility and Prognostic Value of Right Atrial Function in Pulmonary Hypertension.

Background Although right atrial (RA) enlargement is an established marker for adverse outcomes, the prognostic importance of RA dysfunction independent of RA size in pulmonary arterial hypertension is not known. Methods and Results Study subjects with pulmonary arterial hypertension were prospectively enrolled from 2010 to 2014. RA function was measured using RA speckle-tracking longitudinal strain and strain rate (SR) during each phase of the cardiac cycle: (1) RA reservoir (peak longitudinal strain, peak systolic SR), (2) RA conduit (peak early diastolic SR), and (3) RA active contraction (peak active contraction strain, peak contraction SR). The primary outcome was a composite of time to hospitalization or death assessed on follow-up. A total of 63 subjects had complete echocardiographic data. Of these, 91% were females, and the mean age was 58±12 years. During the follow-up period (range: 1-58 months), 39 were hospitalized or had died. After multivariable adjustment for age, sex, and left atrial size, peak longitudinal strain, peak active contraction strain, and peak early diastolic SR were significantly associated with increased risk of the composite outcome ( P=0.0005, P=0.0167, and P=0.0054, respectively). Conclusions RA dysfunction independently predicts mortality and hospitalizations in patients with pulmonary arterial hypertension.

Imaging Diagnosis of Right Ventricle Involvement in Chagas Cardiomyopathy.

Right ventricle (RV) is considered a neglected chamber in cardiology and knowledge about its role in cardiac function was mostly focused on ventricular interdependence. However, progress on the understanding of myocardium diseases primarily involving the RV led to a better comprehension of its role in health and disease. In Chagas disease (CD), there is direct evidence from both basic and clinical research of profound structural RV abnormalities. However, clinical detection of these abnormalities is hindered by technical limitations of imaging diagnostic tools. Echocardiography has been a widespread and low-cost option for the study of patients with CD but, when applied to the RV assessment, faces difficulties such as the absence of a geometrical shape to represent this cavity. More recently, the technique has evolved to a focused guided RV imaging and myocardial deformation analysis. Also, cardiac magnetic resonance (CMR) has been introduced as a gold standard method to evaluate RV cavity volumes. CMR advantages include precise quantitative analyses of both LV and RV volumes and its ability to perform myocardium tissue characterization to identify areas of scar and edema. Evolution of these cardiac diagnostic techniques opened a new path to explore the pathophysiology of RV dysfunction in CD.

Usefulness of Myocardial Annular Velocity Change During Mental Stress to Predict Cardiovascular Outcome in Patients With Coronary Artery Disease (From the Responses of Mental Stress-Induced Myocardial Ischemia to Escitalopram Treatment Trial).

Mental stress-induced myocardial ischemia is common and a prognostic factor of adverse cardiovascular outcomes in patients with coronary artery disease (CAD). The present study aimed at examining associations between mental stress-induced myocardial annular velocity (MAV) and cardiovascular outcome in patients with CAD. MAV, specifically, diastolic early (e'), diastolic late (a'), and systolic (s') velocities were obtained at rest and during mental stress testing in 224 patients with clinically stable CAD. Using Cox regression models, age, sex, and baseline-adjusted mental stress-induced MAV measures were examined as predictors of a priori defined composite event term that comprised all-cause mortality and/or nonfatal cardiovascular events, resulting in an unplanned hospitalization (major adverse cardiovascular events [MACE]). Median follow-up was 4 years. The sample was predominantly male, Caucasian with New York Heart Association functional class I and a mean age of 63 ± 10.2 years. MS-induced changes in e' (hazard ratio [HR] = .73) and s' (HR = .73) were significant (p <0.05) predictors of MACE, and the change in a' (HR = .74) was marginal (p = 0.05). The pattern of the relation for each MAV measure was such that patients with a greater decrease in e' and/or s' velocity had a higher probability of experiencing an MACE, and the association of the change in a' and MACE was marginal (p = 0.05), but the same tendency. The associations between MS-induced values of e' and a' for MACE were independent of resting levels. Mental stress-induced MAV changes independently predict an adverse cardiovascular outcome in patients with stable CAD.

Right Ventricular Systolic Dysfunction in Chagas Disease Defined by Speckle-Tracking Echocardiography: A Comparative Study with Cardiac Magnetic Resonance Imaging.

BACKGROUND: Chagas disease leads to biventricular heart failure, usually with prominent systemic congestion. Although echocardiography is widely used in clinical routine, the utility of echocardiographic parameters to detect right ventricular (RV) systolic dysfunction in patients with Chagas disease is unknown. We sought to study the diagnostic value of echocardiography, including speckle-tracking parameters, to distinguish individuals with RV systolic dysfunction from those with normal RV systolic function in Chagas disease using cardiac magnetic resonance (CMR) as the reference method. METHODS: In this cross-sectional study, 63 individuals with Chagas disease underwent echocardiography and CMR evaluations. Conventional echocardiographic parameters for RV functional evaluation were tricuspid annular plane systolic excursion, RV systolic excursion velocity, fractional area change, and RV index of myocardial performance. Strain and strain rate were obtained by two-dimensional speckle-tracking echocardiography and defined as "RV free wall," when based only in segments from RV free wall, or "RV free wall and septum," when segments from both free RV wall and interventricular septum were included. RV systolic dysfunction was defined as RV ejection fraction (RVEF) < 50% by CMR. RESULTS: Mean age was 56 ± 14 years, and 58.7% of the patients were men. RV systolic dysfunction was detected by CMR in 18 (28.6%) individuals. RV free wall strain showed the highest correlation with RVEF by CMR (r = -0.62, P < .001), followed by fractional area change (r = 0.56, P < .001), RV free wall and septum strain (r = -0.54, P < .001), RV free wall and septum strain rate (r = -0.47, P < .001), RV free wall strain rate (r = -0.45, P < .001), and RV systolic excursion velocity (r = 0.30, P = .016). The RV index of myocardial performance and tricuspid annular plane systolic excursion showed a small and not significant correlation with RVEF (r = -0.20, P = .320; r = 0.14; P = .289, respectively). Using predefined cutoffs for RV systolic dysfunction, RV free wall strain (>-22.5% for men and >-23.3% for women) exhibited the highest area under the receiver operating characteristic curve (area under the curve = 0.829) to differentiate the presence from the absence of RV systolic dysfunction in Chagas disease, with a sensitivity and specificity of 67% and 83%, respectively. CONCLUSIONS: RV free wall strain is an appropriate and superior echocardiographic variable for evaluating RV systolic function in Chagas disease, and it should be the method of choice for this purpose.

Evaluation of Right Ventricular Systolic Function in Chagas Disease Using Cardiac Magnetic Resonance Imaging.

BACKGROUND: Right ventricular (RV) impairment is postulated to be responsible for prominent systemic congestion in Chagas disease. However, occurrence of primary RV dysfunction in Chagas disease remains controversial. We aimed to study RV systolic function in patients with Chagas disease using cardiac magnetic resonance. METHODS AND RESULTS: This cross-sectional study included 158 individuals with chronic Chagas disease who underwent cardiac magnetic resonance. RV systolic dysfunction was defined as reduced RV ejection fraction based on predefined cutoffs accounting for age and sex. Multivariable logistic regression was used to verify the relationship of RV systolic dysfunction with age, sex, functional class, use of medications for heart failure, atrial fibrillation, and left ventricular systolic dysfunction. Mean age was 54±13 years, 51.2% men. RV systolic dysfunction was identified in 58 (37%) individuals. Although usually associated with reduced left ventricular ejection fraction, isolated RV systolic dysfunction was found in 7 (4.4%) patients, 2 of them in early stages of Chagas disease. Presence of RV dysfunction was not significantly different in patients with indeterminate/digestive form of Chagas disease (35.7%) compared with those with Chagas cardiomyopathy (36.8%) (P=1.000). CONCLUSIONS: In chronic Chagas disease, RV systolic dysfunction is more commonly associated with left ventricular systolic dysfunction, although isolated and early RV dysfunction can also be identified.

Matrix metalloproteinase inhibition attenuates right ventricular dysfunction and improves responses to dobutamine during acute pulmonary thromboembolism.

Activated matrix metalloproteinases (MMPs) cause cardiomyocyte injury during acute pulmonary thromboembolism (APT). However, the functional consequences of this alteration are not known. We examined whether doxycycline (a MMP inhibitor) improves right ventricle function and the cardiac responses to dobutamine during APT. APT was induced with autologous blood clots (350 mg/kg) in anaesthetized male lambs pre-treated with doxycycline (Doxy, 10 mg/kg/day, intravenously) or saline. Non-embolized control lambs received doxycycline pre-treatment or saline. The responses to intravenous dobutamine (Dob, 1, 5, 10 µg/kg/min.) or saline infusions at 30 and 120 min. after APT induction were evaluated by echocardiography. APT increased mean pulmonary artery pressure and pulmonary vascular resistance index by ~185%. Doxycycline partially prevented APT-induced pulmonary hypertension (P < 0.05). RV diameter increased in the APT group (from 10.7 ± 0.8 to 18.3 ± 1.6 mm, P < 0.05), but not in the Doxy+APT group (from 13.3 ± 0.9 to 14.4 ± 1.0 mm, P > 0.05). RV dysfunction on stress echocardiography was observed in embolized lambs (APT+Dob group) but not in embolized animals pre-treated with doxycycline (Doxy+APT+Dob). APT increased MMP-9 activity, oxidative stress and gelatinolytic activity in the RV. Although doxycycline had no effects on RV MMP-9 activity, it prevented the increases in RV oxidative stress and gelatinolytic activity (P < 0.05). APT increased serum cardiac troponin I concentrations (P < 0.05), doxycycline partially prevented this alteration (P < 0.05). We found evidence to support that doxycycline prevents RV dysfunction and improves the cardiac responses to dobutamine during APT.

Mitral valve prolapse and anxiety disorders.

We investigated whether there is an association between anxiety disorders and mitral valve prolapse. We compared mitral valve prolapse prevalence in individuals with panic disorder (n = 41), social anxiety disorder (n = 89) and in healthy controls (n = 102) in an attempt to overcome the biases of previous studies. Our results show no associations between panic disorder or social anxiety disorder and mitral valve prolapse, regardless of the diagnostic criteria employed, and that the relationship between these conditions seems not to be clinically relevant.

Myocardial ultrasonic tissue characterization in patients with thyroid dysfunction.

BACKGROUND: Structural myocardial abnormalities have been extensively documented in hypothyroidism. Experimental studies in animal models have also shown involvement of thyroid hormones in gene expression of myocardial collagen. This study was planned to investigate the ability of ultrasonic tissue characterization, as evaluated by integrated backscatter (IBS), to early identify myocardial involvement in thyroid dysfunction. PATIENTS AND METHODS: We studied 15 patients with hyperthyroidism (HYPER), 8 patients with hypothyroidism (HYPO), 14 patients with subclinical hypothyroidism (SCH) and 19 normal (N) subjects, who had normal LV systolic function. After treatment, 10 HYPER, 6 HYPO, and 8 SCH patients were reevaluated. IBS images were obtained and analyzed in parasternal short axis (papillary muscle level) view, at left ventricular (LV) posterior wall. The following IBS variables were analyzed: 1) the corrected coefficient (CC) of IBS, obtained by dividing IBS intensity by IBS intensity measured in a rubber phantom, using the same equipment adjustments, at the same depth; 2) cardiac cyclic variation (CV) of IBS--peak-to-peak difference between maximal and minimal values of IBS during cardiac cycle; 3) cardiac cyclic variation index (CVI) of IBS--percentual relationship between the cyclic variation (CV) and the mean value of IBS intensity. RESULTS: CC of IBS was significantly larger (p < 0.05) in HYPER (1.57 +/- 0.6) and HYPO (1.53 +/- 0.3) as compared to SCH (1.32 +/- 0.3) or N (1.15 +/- 0.27). The CV (dB) (HYPO: 7.5 +/- 2.4; SCH: 8.2 +/- 3.1; HYPER: 8.2 +/- 2.0) and the CVI (HYPO: 35.6 +/- 19.7%; SCH: 34.7 +/- 17.5%; HYPER: 37.8 +/- 11.6%) were not significantly different in patients with thyroid dysfunction as compared to N (7.0 +/- 2.0 and 44.5 +/- 15.1%). CONCLUSIONS: CC of IBS was able to differentiate cardiac involvement in patients with overt HYPO and HYPER who had normal LV systolic function. These early myocardial structural abnormalities were partially reversed by drug therapy in HYPER group. On the other hand, although mean IBS intensity tended to be slightly larger in patients with SCH as compared to N, this difference was not statistical significant.

Bloqueio atrioventricular e endocardite infecciosa em prótese valvar / Atrioventricular block and infectious endocarditis in valve prosthesis

A endocarditre infecciosa é uma infecção grave, rara e pouco diagnosticada. O presente relato de caso visa chamar a atenção para o diagnóstico de endocardite infecciosa complicada, na presença de distúrbios de condução atrioventricular. Trata-se de um paciente do sexo masculino, 68 anos, portador de prótese valvar aórtica biológica, há 5 anos, atendido na sala de emergência de hospital terciário, com quadro de tosse com expectoração clara, dispnéia em repouso (há 3 meses) e febre (há 01 dia). Eletrocardiograma com bloqueio atrioventricular total e ecocardiograma transesofágico, com vegetações nos folhetos da prótese biológica aórtica, abscesso e insuficiência perivalvares.

Isoproterenol induces primary loss of dystrophin in rat hearts: correlation with myocardial injury.

The mechanism of isoproterenol-induced myocardial damage is unknown, but a mismatch of oxygen supply vs. demand following coronary hypotension and myocardial hyperactivity is the best explanation for the complex morphological alterations observed. Severe alterations in the structural integrity of the sarcolemma of cardiomyocytes have been demonstrated to be caused by isoproterenol. Taking into account that the sarcolemmal integrity is stabilized by the dystrophin-glycoprotein complex (DGC) that connects actin and laminin in contractile machinery and extracellular matrix and by integrins, this study tests the hypothesis that isoproterenol affects sarcolemmal stability through changes in the DGC and integrins. We found different sensitivity of the DGC and integrin to isoproterenol subcutaneous administration. Immunofluorescent staining revealed that dystrophin is the most sensitive among the structures connecting the actin in the cardiomyocyte cytoskeleton and the extracellular matrix. The sarcomeric actin dissolution occurred after the reduction or loss of dystrophin. Subsequently, after lysis of myofilaments, gamma-sarcoglycan, beta-dystroglycan, beta1-integrin, and laminin alpha-2 expressions were reduced followed by their breakdown, as epiphenomena of the myocytolytic process. In conclusion, administration of isoproterenol to rats results in primary loss of dystrophin, the most sensitive among the structural proteins that form the DGC that connects the extracellular matrix and the cytoskeleton in cardiomyocyte. These changes, related to ischaemic injury, explain the severe alterations in the structural integrity of the sarcolemma of cardiomyocytes and hence severe and irreversible injury induced by isoproterenol.

Does the association between mitral valve prolapse and panic disorder really exist?

OBJECTIVE: Although the possible relationship between panic disorder and mitral valve prolapse (MVP) attracted considerable research interest in the 1980s and 1990s, the reported prevalence of MVP in these patients has been inconsistent and widely variable. Clinical and epidemiologic studies have produced controversial data on possible association or definite causal relationship between these 2 entities. The primary objective of the present review was to summarize the current state of knowledge on the association between panic disorder and MVP, including the influence of diagnostic criteria for MVP on the controversial results. DATA SOURCES: We searched MEDLINE, LILACS, and EMBASE databases using the keywords panic and mitral. Inclusion criteria were articles concerning the reciprocal association of MVP and panic disorder, published from the earliest dates available through December 2006. STUDY SELECTION: All relevant articles published in English, Spanish, or Portuguese and reporting original data related to the association of MVP and panic disorder were included. Forty articles fulfilling the criteria for inclusion in this review were identified. DATA SYNTHESIS: Even though the reported prevalence of MVP in panic disorder varied from 0% to 57%, a significant association between the 2 disorders was documented in 17 of the 40 studies. Such inconsistent results were due to sampling biases in case or control groups, widely different diagnostic criteria for MVP, and lack of reliability of MVP diagnosis. None of the reviewed studies used the current state-of-the-art diagnostic criteria for MVP to evaluate the volunteers. Apparently, the more elaborate the study methodology, the lower the chance to observe a significant relationship between these 2 conditions. CONCLUSIONS: Published results are insufficient to definitely establish or to exclude an association between MVP and panic disorder. If any relationship does actually exist, it could be said to be infrequent and mainly occur in subjects with minor variants of MVP. To clarify this intriguing issue, future studies should mainly focus on the observed methodological biases and particularly should use the current criteria for MVP as the standard for evaluation.

Double-chambered right ventricle in an adult patient diagnosed by transthoracic echocardiography.

BACKGROUND: Double-chambered right ventricle is a rare congenital disease frequently misdiagnosed in the adult patient. An anomalous muscle band divides the right ventricle in two cavities causing variable degree of obstruction. Although echocardiography is considered a useful method for the diagnosis of this pathology in children, it has been recognized the transthoracic scanning limitation in adults. CASE PRESENTATION: A 29 year-old patient with double-chambered right ventricle presenting mild exercise intolerance referred for follow up of a known ventricular septal defect in whom a complete diagnosis was obtained based only on transthoracic two dimensional echocardiography without the needing of cardiac catheterization. CONCLUSION: Based on non invasive echocardiographic diagnosis, patient was referred to surgical correction, which was completely successful.