Ventricular Dysfunction Right – ABC CARDIOL

ABC

Editorial

The Right Way to Identify Bad Cardiorespiratory Fitness: Look to the Right

Willian R. Menegazzo et al. Anderson Donelli da Silveira

The right ventricle (RV), previously known as the forgotten ventricle, is progressively gaining attention as a strong indicator of poorer prognosis in heart disease.^, Besides prognostic implications, RV dysfunction is associated with worse cardiorespiratory fitness (CRF), independently of other anatomic and functional variables.^, Unfortunately, the current treatment strategies for RV failure do not confer the same clinical and prognostic benefits of the left ventricle (LV) failure,^, which limits its management and warrants new treatment strategies.

Ramirez et al. accessed this important topic by studying the RV function on 109 patients with ST-elevation myocardial (STEMI), its association with CRF, and its improvement after cardiac rehabilitation (CR) in a single center in Monterrey, Mexico. Their primary goal was to evaluate the association between RV function and CRF in this population, and the secondary objectives were to analyze the CRF before and after a program of CR in patients with or without RV dysfunction. They evaluated exercise tolerance through cardiopulmonary exercise testing and RV longitudinal function through echocardiographic measurement of the S’ Doppler wave of the tricuspid annulus and the tricuspid annular posterior systolic excursion and RV radial function through RV fractional area change. The population was mainly male gender (83%), with anterior STEMI (55%), median LV ejection fraction of 49%, and normal RV function (90%). They have shown an association and correlation between RV radial and longitudinal dysfunction and CRF before and after CR. The main finding is that RV dysfunction evaluated after STEMI and before CR, being radial or longitudinal, was associated with a lack of improvement of at least 1 Metabolic Equivalent Task after a program of CR (p = 0.028 for RV radial dysfunction and p = 0.008 for RV longitudinal dysfunction). The authors concluded that RV dysfunction in STEMI patients is associated and correlated with poorer exercise capacity and functional class before CR and that CR improved CRF. This helps to identify a subgroup of patients with a higher risk of being symptomatic, with a worse prognosis and possibly better candidates for CR.

[…]

Read Full Article

ABCIC

Case Report

Giant Right Coronary Artery Aneurysm with Arteriovenous Fistula

Maria Eduarda Menezes de Siqueira et al. Mayra Isabel Dias Ana Claudia Vincezi Raudan Uski Luciano Figueiredo de Aguiar Filho

Introduction

Coronary artery aneurysm (CAA) is defined as a dilation that exceeds the normal diameter of the adjacent artery or the diameter of the patient’s largest coronary artery by 1.5 times. Some authors consider a giant coronary aneurysm when the diameter is > 20 mm, whereas the American Heart Association defines giant aneurysms as those > 8 mm. Giant CAA is a rare pathology with an approximate incidence of 0.02%. We report a case of giant right coronary artery aneurysm with fistula to the coronary sinus, appearing as a giant “mass”.

[…]

Read Full Article

IJCS

Editorial

Advanced Echocardiographic Techniques for the Diagnosis of Subclinical Right Ventricular Dysfunction in Chronic Obstructive Pulmonary Disease

Silvio Henrique Barberato

Chronic obstructive pulmonary disease (COPD) is a common and treatable disease in the general population, accounting for high morbidity and mortality rates. In patients with severe COPD, hypoxemia is the main cause of complications such as pulmonary hypertension (PH) and right ventricle (RV) dysfunction. However, the presence of RV vascular structural and functional changes may occur in the early stages of COPD, even before significant hypoxemia or PH. Subclinical RV dysfunction often precedes the development of signs and symptoms of RV failure; thus, there is an evident need to detect it from the onset of the disease.

The importance of the RV in cardiovascular physiology has been underestimated for decades. Previously considered a mere conduit, the chamber is now known to play a major role in maintaining global cardiac function intact. Impairment of RV systolic function is an essential determinant of clinical outcomes in different scenarios and should thus be considered in the individualized management of patients.^,

[…]

Read Full Article

IJCS

Original Article

Chronic Obstructive Pulmonary Disease: The Role of Myocardial Deformation Indices and Right Ventricle Three-Dimensional Echocardiography

Claudia Myriam Amaral Botelho et al. José Luiz Barros Pena Bruno Rezende Passos Paulo Roberto Latorre Fortes Maria da Consolação Vieira Moreira

Abstract

Background:

Right ventricular dysfunction is a major complication in chronic obstructive pulmonary disease (COPD) and, despite its prognostic implications, is rarely considered in routine clinical analysis.

Objectives:

To compare RV function variables with standard and advanced echocardiographic techniques in patients with stable COPD and controls.

Methods:

Twenty COPD patients classified as GOLD ≥ II (13 men aged 68.4 ± 8.3 years) and 20 matched controls were compared. Myocardial strain/strain rate indices were obtained by tissue Doppler and two-dimensional speckle tracking echocardiography. Right ventricular ejection fraction was obtained with three-dimensional software. Free wall myocardial thickness (FWMT) and tricuspid annular systolic excursion (TAPSE) were also measured. Numerical variables were compared between groups with Student’s t-test or the Mann-Whitney test. Associations between categorical variables were determined with Fisher’s exact test. P-values < 0.05 were considered statistically significant.

Results:

All myocardial deformation indices, particularly global longitudinal strain (-17.2 ± 4.4 vs -21.2: ± 4.4 = 0.001) and 3D right ventricular ejection fraction (40.8 ± 9.3% vs 51.1 ± 6.4% p <0.001) were reduced in COPD patients. These patients presented higher right ventricular FWMT and lower TAPSE values than controls.

Conclusion:

Myocardial deformation indices, either tissue Doppler or speckle tracking echocardiography and 3D right ventricular ejection fraction, are robust markers of right ventricular dysfunction in patients with stable COPD. Assessing global longitudinal strain by speckle tracking echocardiography is a more practical and reproducible method.

Read Full Article

ABCIC

Case Report

Ruptured Right Sinus of Valsalva Aneurysm with Right Ventricular Fistula

Carolina Santana dos Reis Gonçalves et al. Rafael Rocha Silva Marta Fernandes Lima

[…]

Read Full Article

ABCIC

Case Report

Right Ventricular Myxoma

Cristina Schneider et al. Maria Natividade Santos Costa Lopes Simone Ferreira Leite Camila Costa Oliveira … Nestor Sabatovicz Jr Maria Cristina Resende

[…]

Read Full Article

ABCIC

Editorial

My Approach to Assessment of Right Ventricle Function

Claudia Regina Pinheiro de Castro Grau

[…]

Read Full Article

ABCIC

Editorial

My Approach to Assessing Right Ventricular Strain

Marcela Momesso et al. Cintia Galhardo Tressino Rodrigo Bellio de Mattos Barretto David Le Bihan

[…]

Read Full Article

ABC

Research Letter

Persistent Aneurysm of the Right Coronary Artery, Even after Correction of a Fistula with the Right Ventricle

Introduction

Among the coronary-cavitary fistulas, the most commonly found type corresponds to that involving the right coronary artery and the right cardiac cavities, with corresponding volume overload due to arteriovenous deviation. The clinical manifestations correspond to heart failure, angina with myocardial infarction and arrhythmias. A continuous murmur easily suggests the diagnosis of a congenital defect, which is consolidated by the imaging examinations. Other fistulas should always be suspected in the differential diagnosis, such as the patent ductus arteriosus, aortopulmonary window, systemic-pulmonary collaterals, and fistulas of the sinus of Valsalva with the right ventricle cavity. Cardiac surgery and / or percutaneous interventions comprise the therapeutic basis for fistula resolution. Little is said, however, about the evolution after the procedures, given that the previous coronary dilation persists and may constitute another evolution problem in the longer term.

This aspect comprises the main reason for this assessment.

[…]

Read Full Article

ABC

Original Article

Long-Term Clinical and Hemodynamic Outcomes after Heart Transplantation in Patients Pre-Treated with Sildenafil

Sofia Lázaro Mendes et al. Nadia Moreira Manuel Batista Ana Rita Ferreira … Ana Vera Marinho David Prieto Rui Baptista Susana Costa Fatima Franco Mariano Pego Manuel de Jesus Antunes

Abstract

Background

Elevated pulmonary vascular resistance remains a major problem for heart transplant (HT) candidate selection.

Objective

This study sought at assess the effect of pre-HT sildenafil administration in patients with fixed pulmonary hypertension.

Methods

This retrospective, single-center study included 300 consecutive, HT candidates treated between 2003 and 2013, in which 95 patients had fixed PH, and of these, 30 patients were treated with sildenafil and eventually received a transplant, forming Group A. Group B included 205 patients without PH who underwent HT. Pulmonary hemodynamics were evaluated before HT, as well as 1 week after and 1 year after HT. Survival was compared between the groups. In this study, a p value < 0.05 was considered statistically significant.

Results

After treatment with sildenafil but before HT, PVR (-39%) and sPAP (-10%) decreased significantly. sPAP decreased after HT in both groups, but it remained significantly higher in group A vs. group B (40.3 ± 8.0 mmHg vs 36.5 ± 11.5 mmHg, p=0.022). One year after HT, sPAP was 32.4 ± 6.3 mmHg in group A vs 30.5 ± 8.2 mmHg in group B (p=0.274). The survival rate after HT at 30 days (97% in group A versus 96% in group B), at 6 months (87% versus 93%) and at one year (80% vs 91%) were not statistically significant (Log-rank p=0.063). After this first year, the attrition rate was similar among both groups (conditional survival after 1 year, Log-rank p=0.321).

Conclusion

In patients with severe PH pre-treated with sildenafil, early post-operative hemodynamics and prognosis are numerically worse than in patients without PH, but after 1 year, the medium to long-term mortality proved to be similar. (Arq Bras Cardiol. 2021; 116(2):219-226)

Read Full Article

ABC

Original Article

Impaired Right Ventricular Function in Heart Transplant Rejection

Luciana J. B. M. Carrion et al. Alice Sperotto Raffaela Nazario Livia A. Goldraich … Nadine Clausell Luís Eduardo Rohde Angela Barreto Santiago Santos

Abstract

Background:

The practice of screening for complications has provided high survival rates among heart transplantation (HTx) recipients.

Objectives:

Our aim was to assess whether changes in left ventricular (LV) and right ventricular (RV) global longitudinal strain (GLS) are associated with cellular rejection.

Methods:

Patients who underwent HTx in a single center (2015 – 2016; n = 19) were included in this retrospective analysis. A total of 170 biopsies and corresponding echocardiograms were evaluated. Comparisons were made among biopsy/echocardiogram pairs with no or mild (0R/1R) evidence of cellular rejection (n = 130 and n = 25, respectively) and those with moderate (2R) rejection episodes (n=15). P-values < 0.05 were considered statistically significant

Results:

Most patients were women (58%) with 48 ± 12.4 years of age. Compared with echocardiograms from patients with 0R/1R rejection, those of patients with 2R biopsies showed greater LV posterior wall thickness, E/e’ ratio, and E/A ratio compared to the other group. LV systolic function did not differ between groups. On the other hand, RV systolic function was more reduced in the 2R group than in the other group, when evaluated by TAPSE, S wave, and RV fractional area change (all p < 0.05). Furthermore, RV GLS (−23.0 ± 4.4% in the 0R/1R group vs. −20.6 ± 4.9% in the 2R group, p = 0.038) was more reduced in the 2R group than in the 0R/1R group.

Conclusion:

In HTx recipients, moderate acute cellular rejection is associated with RV systolic dysfunction as evaluated by RV strain, as well as by conventional echocardiographic parameters. Several echocardiographic parameters may be used to screen for cellular rejection.

Read Full Article

ABC

Original Article

Echocardiographic Correlation between Right Ventricular Function and Left Atrial Volume

Liz Andréa Villela Baroncini et al. Lucas José Lira Borges Ana Cristina Camarozano Daniela de Castro Carmo … Rubens Zenobio Darwich Jeronimo Antonio Fortunato Junior

Abstract

Background:

Few reports exist on the relationship of the left ventricular diastolic dysfunction (LVDD) with its most important features including enlargement of the left atrium and left ventricular hypertrophy (LVH), and with the right ventricular (RV) function.

Objective:

To determine the correlation between the left atrial size and the RV function and dimensions in patients with and without LVDD and LVH.

Methods:

Fifty patients were included, 25 (40% men) of them with LVDD, aged 67.1 ± 10.6 years (study group) and 25 without LVDD (52% men) aged 49.9 ± 16.3 years (control group). Patients underwent transthoracic echocardiography with evaluation of the left atrial size and volume (LAV), LVDD, LVH, and RV function and dimensions. P-values < 0.05 were considered statistically significant.

Results:

LAV > 34 mL/m² and left atrial size > 40 mm were associated with lower absolute values of tricuspid annular plane systolic excursion (TAPSE) and RV lateral S’ (p ≤ 0.001, Pearson’s correlation coefficient -0.4 and -0.38, respectively) in the study group. Patients in the study group showed higher incidence of LVH (p = 0.02) and greater left atrial diameter (p = 0.03) compared with the control group. In addition, greater left atrial diameter (p = 0.02) and LAV (p = 0.01) values were found in patients with LVDD grade II compared with LVDD grade I.

Conclusions:

The present study determined, for the first time, the correlation of left atrial enlargement with progressive RV dysfunction in patients with LVDD.

Read Full Article

ABC

Original Article

Right Atrial Deformation Analysis in Cardiac Amyloidosis – Results from the Three-Dimensional Speckle-Tracking Echocardiographic MAGYAR-Path Study

Attila Nemes et al. Dóra Földeák Péter Domsik Anita Kalapos … Árpád Kormányos Zita Borbényi Tamás Forster

Abstract

Background:

Light-chain (AL) cardiac amyloidosis (CA) is characterized by fibril deposits, which are composed of monoclonal immunoglobulin light chains. The right ventricle is mostly involved in AL-CA and impairment of its function is a predictor of worse prognosis.

Objectives:

To characterize the volumetric and functional properties of the right atrium (RA) in AL-CA by three-dimensional speckle-tracking echocardiography (3DSTE).

Methods:

A total of 16 patients (mean age: 64.5 ± 10.1 years, 11 males) with AL-CA were examined. Their results were compared to that of 15 age- and gender-matched healthy controls (mean age: 58.9 ± 6.9 years, 8 males). All cases have undergone complete two-dimensional Doppler and 3DSTE. A two-tailed p value of less than 0.05 was considered statistically significant.

Results:

Significant differences could be demonstrated in RA volumes respecting cardiac cycle. Total (19.2 ± 9.3% vs. 27.9 ± 10.7%, p = 0.02) and active atrial emptying fractions (12.1 ± 8.1 vs. 18.6 ± 9.8%, p = 0.05) were significantly decreased in AL-CA patients. Peak global (16.7 ± 10.3% vs. 31.2 ± 19.4%, p = 0.01) and mean segmental (24.3 ± 11.1% vs. 38.6 ± 17.6%, p =0.01) RA area strains, together with some circumferential, longitudinal and segmental area strain parameters, proved to be reduced in patients with AL-CA. Global longitudinal (4.0 ± 5.2% vs. 8.2 ± 5.5%, p = 0.02) and area (7.8 ± 8.1% vs. 15.9 ± 10.3%, p = 0.03) strains at atrial contraction and some circumferential and area strain parameters at atrial contraction were reduced in AL-CA patients.

Conclusion:

Significantly increased RA volumes and deteriorated RA functions could be demonstrated in AL-CA.

Read Full Article

ABC

Editorial

Right Ventricular Dysfunction in Lupus Patients With Pulmonary Hypertension

Silvio Henrique Barberato

The importance of the right ventricle in cardiovascular physiology has been underestimated for decades. Previously considered a mere conduit, the right ventricle is currently known to play a major role in maintaining global cardiac function intact. In parallel, right ventricular (RV) systolic function has been shown to be an essential determinant of clinical outcomes in several scenarios, and should thus be considered in the individualized management of patients. The need to diagnose RV dysfunction is evident. Because of its wide availability, echocardiography is the most frequently used imaging test in clinical practice to assess RV size and function. That assessment can be hindered by the complex RV anatomy; thus, important international societies of cardiovascular imaging have recommended the routine and systematic addition of several echocardiographic measurements and techniques.^, That approach includes conventional parameters, such as RV basal diameter (normal ≤ 41 mm) and tricuspid annular plane systolic excursion (TAPSE – normal ≥ 17 mm), as well as advanced parameters, such as the s wave of the RV free wall on tissue Doppler (normal ≥ 9.5 cm/s), ejection fraction on 3D echocardiography (normal ≥ 45%) and longitudinal strain of the RV free wall (normal ≥ -20%).

In this scenario, strain (systolic shortening percentage) and strain rate (shortening rate), calculated by speckle tracking on two-dimensional echocardiography (2D speckle tracking or 2D-STE), emerge as alternatives in the RV systolic function analysis. The longitudinal strain of the RV free wall, excluding the ventricular septum, showed prognostic value in patients with signs and symptoms of cardiopulmonary disease, such as heart failure, myocardial infarction, pulmonary hypertension, congenital heart diseases, RV arrhythmogenic cardiomyopathy and amyloidosis. Right ventricular longitudinal strain is a parameter less dependent on the angle, with less intra- and interobserver variability, that can apparently detect early RV dysfunction. Its drawbacks include the high dependence on image quality and the variability of the software of the equipment available in the market. Recently an international consensus has been reached to standardize the use of 2D-STE to obtain RV strain. The specific use of right-ventricle-focused apical 4-chamber view is recommended for correct strain measurement. Extreme care should be taken to define the region of interest (ROI) of the endocardial border (suggested ROI: 5 mm), because of the RV shape and thin walls. The pericardium should be excluded from the analysis, because of the risk of strain underestimation.

[…]

Read Full Article

ABC

Review Article

Case 1/2018 – Young Male with Heart Disease Expressed Mainly as Ventricular Arrhythmia, Right Ventricular Dysfunction and Syncope

Desiderio Favarato et al. Luiz Alberto Benvenuti

Clinical aspects

The patient had syncope episodes since the age of 20 years, and heart failure since the age of 30 years, undergoing cardiac transplantation at the age of 36 years.

Since symptom onset, heart disease with marked left ventricular dilatation and moderate dysfunction was detected. The exercise test revealed frequent ventricular arrhythmia. His syncope episodes were attributed to malignant ventricular arrhythmias, and a cardioverter defibrillator was implanted.

[…]

Read Full Article

IJCS

Case Report

Improvement of Pacing-Induced Dyssynchrony by Right Ventricular Septal Stimulation in a Child with Tetralogy of Fallot

Alexander González Guillen et al. Michel Cabrera Ortega Francisco Díaz Ramírez Dunia Bárbara Benítez Ramos

Introduction

Complete atrioventricular block (CAVB) is not an uncommon complication after surgical correction of tetralogy of Fallot (TOF). The choice of the ventricular pacing site in patients requiring pacemaker therapy depends on factors such as age, weight, presence of a venous anomaly, and intracardiac short -circuit. The harmful effects of ventricular pacing are most pronounced during right ventricular (RV) stimulation. Even then, RV pacing sites have been determined to be optimal in some patients with and without congenital heart disease.

[…]

Read Full Article

ABC

Original Article

Right Ventricular Doppler Echocardiographic Study of Indeterminate Form of Chagas Disease

Rogério Gomes Furtado et al. Daniela do Carmo Rassi Frota João Batista Masson Silva Minna Moreira Dias Romano … Oswaldo César de Almeida Filho André Schmidt Salvador Rassi

Background:

Patients with indeterminate form of Chagas disease/cardiac normality (ICD/CN) exhibited normal electrocardiograms and chest X-rays; however, more sophisticated tests detected some degree of morphological and functional changes in the heart.

Objective:

To assess the prevalence of systolic and diastolic dysfunction of the right ventricle (RV) in patients with ICD/CN.

Methods:

This was a case–control and prevalence study. Using Doppler two-dimensional echocardiography (2D), 92 patients were assessed and divided into two groups: group I (normal, n = 31) and group II (ICD/CN, n = 61).

Results:

The prevalence of RV systolic dysfunction in patients in groups I and II was as follows: fractional area change (0.0% versus 0.6%), mobility of the tricuspid annulus (0.0% versus 0.0%), and S-wave tissue Doppler (6.4% versus 26.0%, p = 0.016). The prevalence of global disorders such as the right myocardial performance index using tissue Doppler (16.1% versus 27.8%, p = 0.099) and pulsed Doppler (61.3% versus 68%, p = 0.141) and diastolic disorders such as abnormal relaxation (0.0% versus 6.0%), pseudonormal pattern (0.0% versus 0.0%), and restrictive pattern (0.0% versus 0.0%) was not statistically different between groups.

Conclusion:

The prevalence of RV systolic dysfunction was estimated to be 26% (S wave velocity compared with other variables), suggesting incipient changes in RV systolic function in the ICD/CN group.

Read Full Article

ABC

Editorial

Atrial Septal Defect in Adults: Does Repair Always Mean Cure?

Antônio Augusto Lopes et al. Sonia M. F. Mesquita

Atrial septal defect (ASD) is the most prevalent congenital cardiac anomaly in adults, accounting for ~35% of all congenital heart defects. Late presentation is due to the insidious development of right ventricular remodeling, with enlargement of right cardiac chambers. Patients may seek medical attention with symptoms related to right or global myocardial dysfunction, arrhythmias or thromboembolic events. Until recently, pulmonary vasculopathy was assumed to be a rare complication in ASD patients. However, with progressive knowledge and interest in treating pulmonary arterial hypertension (PAH), numbers are changing. Of 1877 adults with congenital heart disease followed up for five years in the European Union, 896 had ASD, with PAH prevalences of 12% and 34% for repaired and unrepaired defects respectively. Fifteen patients had the full picture of the Eisenmenger syndrome.

The fortunate side of the scenario is that the widespread use of echocardiography has allowed a big number of patients to be diagnosed early. Furthermore, transcatheter closure of secundum defects offers a less invasive alternative of repair to patients who fulfill anatomical and size criteria, and may be an appropriate therapeutic option for subjects with paradoxical embolism. Also minimally invasive video-assisted surgical techniques have allowed successful closure of the communications, and represent a new and promising therapeutic approach to patients with ASD. The dark side of the story is: with late presentation, treatments may allow patients to become free from the communications, but not from advanced right ventricular remodeling and failure, severe arrhythmias and pulmonary vasculopathy.

[…]

Read Full Article

ABC

Artigo Original

Hemodynamic effects of experimental acute right ventricular overload

Flávio Brito Filho et al. Kleber Nogueira de Campos Humberto Alves de Oliveira Josué Fernandes … César Augusto Melo e Silva Eduardo Gaio Edwin Roger Parra Paulo Henrique Cândido de Carvalho Paulo Manoel Pêgo Fernandes

BACKGROUND: Acute right ventricular overload is associated with high morbidity and mortality clinical situations such as: extensive lung resection, pulmonary thromboembolism, lung transplantation and high altitude pulmonary edema. Some points of its pathophysiology remain unclear. OBJECTIVE: To assess the hemodynamic effects of experimental acute right ventricular overload in pigs. METHODS: Right ventricular overload was induced through the occlusion of the pulmonary arteries using ligationss. Twenty pigs were used in the study, divided into 04 groups: one control group not subject to pulmonary vascular occlusion, and three right ventricular overload groups subject to occlusion of the following pulmonary arteries: SVD1 (left pulmonary artery); SVD2 (left pulmonary artery and right lower lobe) and SVD3 (left pulmonary artery, right lower lobe and mediastinal lobe), obstructing the pulmonary vasculature in 42, 76 and 82.0% respectively. Hemodynamic variables were measured every 15 minutes during one hour of study. The statistical analysis employed mixed linear models with variance and covariance structures. RESULTS: Group comparisons revealed significant increases in heart rate (p = 0.004), mean pulmonary artery pressure (p = 0.001) and pulmonary capillary wedge pressure (p < 0.0001). There was no significant difference in cardiac index (p = 0.94). CONCLUSION: Despite the severe right ventricular overload promoted by 82.0% obstruction of the pulmonary vasculature and the significant increase in pulmonary arterial pressure, there was no severe cardiovascular dysfunction and/or circulatory shock during the study period.

Read Full Article

ABC

Artigo Original

Intermittent systolic overload promotes better myocardial performance in adult animals

Leonardo Augusto Miana et al. Renato S. Assad Maria C. D. Abduch Guilherme Seva Gomes … Ananda Rigo Nogueira Fernanda Santos Oliveira Bruna Lopes Telles Maria Teresa Souto Gustavo J. Silva Noedir A. G. Stolf

BACKGROUND: Corrected transposition of great arteries often evolves with right ventricular dysfunction. The ventricular preparation for anatomic correction in adult patients has produced disappointing results. OBJECTIVE: To assess right ventricular hypertrophy (RV) induced by conventional and intermittent pulmonary banding (PB) in adult animals. METHODS: Nineteen adult goats were divided into three groups: conventional (six animals), intermittent (six animals) and control (seven animals). The Conventional group underwent fixed PB with cardiac tape, while the intermittent group received PB adjustable device, which generated systolic overload for 12 hours, alternated with 12 hours of rest of RV. The pressures of the RV, pulmonary artery and aorta were measured throughout the study. Echocardiography was performed weekly. After four weeks, the animals were euthanized for morphological evaluation of the ventricles. The Control group was put to euthanasia for analysis at baseline. RESULTS: Pressure overload was lower in the intermittent group (p = 0.001), compared to the conventional group. There was an increase in the thickness of the RV of the Intermittent group measured by echocardiography compared to their baseline values (p < 0.05). The myocardial performance index in the RV group was better in the Intermittent group (p = 0.024), compared to the Conventional group. The groups stimulated showed increased muscle mass compared to the Control group (p = 0.001). There was no difference in myocardial water content. CONCLUSION: The intermittent BP developed hypertrophy of better performance, suggesting this protocol as the preferred method of ventricular preparation.

Read Full Article