Evaluation Of Right Ventricle Research Articles

Echocardiographic evaluation of right ventricle to pulmonary artery coupling in patients undergoing transcatheter aortic valve implantation: a systematic review and meta-analysis

Abstract Background Right Ventricle to Pulmonary Artery (RV/PA) uncoupling, which depicts the inability of RV contractility to match the increasing RV afterload, has recently gained recognition as a simple echocardiography parameter to aid prognosis judgment in patients with RV dysfunction. In Aortic Stenosis (AS) patients, the extent of RV dysfunction and Pulmonary Hypertension (PH) has been linked with poor outcomes, but the prognostic value of RV/PA uncoupling in AS patients undergoing TAVI has not been well-defined. Purpose To investigate the prognostic value of RV/PA uncoupling and its association with echocardiographic parameters in AS patients undergoing TAVI. Methods We conducted a systematic search through Pubmed and Embase to include studies up to February 2024. Studies were eligible if they evaluated the prognostic performance of RV/PA uncoupling in AS patients undergoing TAVI. Random-effects model were employed to pool the adjusted Hazard Ratio (aHR) with inverse-variance weighting method or Relative Risk (RR) with 95% Confidence Interval (95% CI) using Mantel-Haenszel test for categorical outcomes or Weighted Mean Difference (WMD) for numerical outcomes. Risk of bias assessment was conducted using the Newcastle Ottawa Scale (NOS). Results Thirteen studies were included. Out of 4,146 patients, 55.21% were reported to have RV-PA uncoupling prior to TAVI. RV/PA uncoupling was customarily assessed with TAPSE/PASP ratio, with threshold for uncoupling ranging between <0.31–<0.63 mm/mmHg. Follow-up period ranged between 6–65 months. Patients with baseline RV/PA uncoupling had lower LVEF (WMD -9.94% [-4.36– -15.53%]; I2 = 78%), lower TAPSE (WMD -4.98 mm [95% CI -1.15– -8.80]; I2 = 95%), and higher PASP (WMD 19.77 [95% CI 17.02–22.51]; I2 = 0%) compared to patients with RV/PA coupling at baseline. Baseline RV-PA uncoupling was an independent predictor of all-cause mortality (pooled aHR = 2.26 (95% CI 1.36–3.76); I2 = 77%) and composite endpoint of mortality and adverse cardiac or cerebrovascular events (pooled aHR = 2.07 (1.30–3.29); I2 = 24%). However, RV/PA uncoupling was not significantly associated with a higher risk of permanent pacemaker implantation after TAVI (pooled Risk Ratio 1.02 [0.70–1.47]; I2 = 0%). Conclusion Pre-procedural RV/PA uncoupling emerges as an independent predictor of worse prognosis in AS patients undergoing TAVI, contributing to a better understanding of the impact of this parameter on patient outcomes.

ROLE OF RIGHT VENTRICULAR MYOCARDIAL WORK IN THE STRATIFICATION OF PATIENTS AFFECTED BY ADVANCED HEART FAILURE

Abstract Background Currently adopted echocardiographic parameters for the evaluation of right ventricle (RV) are all loading sensitive and their reliability remains poor. RV myocardial work (RVMW) emerged as an innovative non–invasive diagnostic tool that incorporates strain pressure loops and potentially overcomes the aforementioned limitation. No previous studies assessed the variations of RVMW depending on the hemodynamic setting. Aim of the study: To evaluate the different values of RVMW in patients affected by advanced heart failure (AHF) with and without pulmonary hypertension (PH) at right heart catheterization (RHC) and their variations in patients with baseline PH who subsequently achieved PH reversibility. Methods and Results All patients with AHF who underwent RHC and echocardiography within 24h at Istituto Mediterraneo per I Trapianti e Terapie ad Alta Specializzazione (ISMETT) since 01/05/2023 were prospectively enrolled. Patients with baseline documented PH who achieved PH reversibility at RHC underwent a second echcocardiographic assessment under the same hemodynamic conditions. The following components of RVMW were analysed: 1) RV global work index (RVGWI); 2) RV global constructive work (RVGCW); 3) RV global wasted work (RVGWW); 4) RV global work efficiency (RVGWE). Overall, 41 patients were enrolled (16 without PH and 25 with PH). Patients with PH had a higher RVGWI (341±133mmHg% vs 207±104mHg%; p=0.002) and RVGCW (450±153mmHg% vs 294±114mmHg%; p=0.001) compared to those without, while RVGWE did not differ in the two groups (80 ±10mmHg% vs 80 ±15mmHg%; p=0.92). A trend toward a higher RVGWW in patients with PH was observed (89±54mmHg% vs 59 ±66mmHg%; p=0.12). Among the 25 patients with PH, 10 were tested for PH reversibility and this was achieved in 9/10 (90%). RVGWI and RVGCW significantly dropped once PH reversibility was achieved (respectively from 393 ±185mmHg% to 241±67mmHg; p=0.008 and from 435±127mmHg% to 268±67mmHg%; p=0.048). Interestingly, RVGWE remained almost unchanged (from 81±11mmHg% to 79±9mmHg%; p=0.661) while there was a nearly significant trend in RWGWW decrease (from 65±20mmHg% to 41 ±22mmg%; p=0.076). Conclusions Patients affected by AHF and PH have significantly higher RVGWI and RWGCW compared to those without. However, RVGWE is similar between the groups and does not vary depending the hemodynamic setting, potentially identifying this parameter as the most reliable one in patients with AHF.

The quest for determination of standard reference values of right ventricular longitudinal systolic strain: a systematic review and meta-analysis.

Right ventricular function is strongly associated with clinical outcomes in many conditions, and the evaluation of right ventricle (RV) structure and function in patients with cardiopulmonary disorders is an essential component of clinical management. The objective of this study was to determine the normal ranges of right ventricular longitudinal strain (RVLS) measurements derived by two-dimensional (2D) speckle tracking echocardiography (STE) through a systematic review and meta-analysis. A systematic review was performed using PubMed, Cochrane, ClinicalKey, and CINAHL. Search terms covered the concepts of right ventricle, strain, speckle-tracking, and 2D echocardiography with additional filtering for humans and adults over the last decade. The RV four-chamber longitudinal strain (RV4CLS), RV free wall longitudinal strain (RVFWLS), and free wall longitudinal segmental strain values of healthy individuals without cardiopulmonary diseases from 28 studies were assessed. Weighted means were estimated using random-effects models in a meta-analysis. The results show for RV4CLS -24,91%[CI - 25.94; - 23.88, I2 98%], for RVFWLS -27.63%[CI - 28.78; - 26.48, I2 98%], for basal RVFWLS -26.65%[CI - 30.57; - 22.73, I2 99%], mid RVFWLS -27.61%[CI - 30.99; - 24.22, I2 99%] and apical RVFWLS -24.54%[CI - 26.70; - 22.38, I2 98%].This systematic review and meta-analysis showed longitudinal strain values of 2D STE derived RV. No clear reference value for RV strain can be distilled from the literature search due to high statistical heterogeneity between the studies. However, all results of our analysis suggest that the lower reference values for RVLS in the current recommendations with a cut-off value of - 20% is underestimated.

Role of cardiac magnetic resonance in stratifying the prognosis of patients with pulmonary arterial hypertension

Abstract Background Pulmonary arterial hypertension (PAH) is a rare disease characterized by a complex remodeling of heart structures. Cardiac magnetic resonance (CMR) is the gold standard for a non-invasive evaluation of right ventricle (RV) volumes and mass. Purpose To define the relationship between clinical, functional, biochemical, haemodynamic and CMR parameters and survival in patients with PAH. Methods Consecutive patients with PAH referred to our centre underwent clinical, functional, brain natriuretic peptide (BNP) plasma levels, haemodynamic and CMR evaluation. All patients were treated according to current guidelines. Univariate Cox analysis for survival was performed. Parameters with a p-value <0.1 at the univariate analysis were included in the multivariate analysis. Results One hundred forty-seven patients with PAH (mean age 49±17 years, 69% female) were included in the study. Etiology of PAH was: idiopathic/heritable (49%), associated with connective tissue disease (19%), congenital heart disease (12%), portal hypertension/HIV infection (12%) and pulmonary veno-occlusive disease (8%). Thirty-six patients died during follow-up. Parameters significantly associated with mortality at the univariate analysis were age [Hazard Ratio (95% Confidence Interval): 1.043 (1.020–1.067); p<0.001], six-minute walk test (6MWT) [HR: 0.995 (0.993–0.998); p<0.001], WHO-functional class [HR: 2.489 (1.025–6.041); p=0.044], idiopathic-heritable-congenital heart disease aetiology [HR: 0.182 (0.085–0.389); p<0.001], connective tissue disease aetiology [HR: 2.274 (1.099–4.704); p=0.027], pulmonary veno-occlusive disease aetiology [HR: 5.864 (2.328–14.773); p<0.001], right atrial pressure [HR: 1.098 (1.032–1.169); p=0.003], pulmonary artery oxygen saturation [HR: 0.947 (0.921–0.975); p<0.001], BNP levels [HR: 2.214 (1.213–4.039); p=0.010], RV wall thickness [HR: 0.633 (0.399–1.006); p=0.053], RV end diastolic volume [HR: 1.012 (1.003–1.021); p=0.007], RV end systolic volume [HR: 1.014 (1.003–1.024); p=0.011]. Parameters independently associated with mortality at the multivariate analysis were age [HR: 1.035 (1.006–1.064); p=0.018], idiopathic-heritable-congenital heart disease aetiology [HR: 0.355 (0.146–0.860); p=0.022], pulmonary veno-occlusive disease aetiology [HR: 3.129 (1.071–9.143); p=0.037], pulmonary artery oxygen saturation [HR: 0.953 (0.919–0.989); p=0.011], RV wall thickness [HR: 0.527 (0.300–0.927); p=0.026], RV end systolic volume [HR: 1.016 (1.003–1.029); p=0.014]. Conclusion RV wall thickness and RV end-systolic volume are associated with prognosis in patients with PAH independently from clinical and haemodynamic characteristics. These parameters may be used in the overall risk stratification of PAH patients. Funding Acknowledgement Type of funding sources: None.

Echocardiographic evaluation of pulmonary hypertension, right ventricular function, and right ventricular-pulmonary arterial coupling in patients with rheumatoid arthritis.

Rheumatoid arthritis (RA) patients are at increased risk for developing cardiovascular disease, including right heart failure. The evaluation of right ventricle (RV) using the relationship between tricuspid annular plane systolic excursion (TAPSE) and right ventricular systolic pressure (RVSP) is of clinical prognostic relevance. Mild echocardiographic pulmonary hypertension (ePH) has been associated with worse RV function. The aim of this study was to evaluate RV function as measured by TAPSE to RVSP ratio in rheumatoid arthritis patients compared to matched healthy controls. A case-control study with 67 RA patients aged 40 to 75 years that fulfilled the 2010 ACR/EULAR criteria and 45 matching controls was included. A transthoracic echocardiogram was performed to all patients. TAPSE was measured as the distance traveled from end-diastole to end-systole. RVSP was calculated using the modified Bernoulli equation. Comparisons were done using Chi-square and Mann-Whitney's U test or Student's t test. Patients with RA had significantly reduced ventricular function (TAPSE 23 [21-25] vs 25 [23-26], p = 0.033) and TAPSE/RVSP ratio was significantly lower in RA-patients than controls (TAPSE to RVSP ratio 0.809 [0.67-1.01] vs 0.933 [0.79-1.11], p = 0.009). RA-patients with mild ePH had similar RV function, evaluated by TAPSE, in comparison to RA-patients with normal RVSP. RA-patients had worse RV function measured by TAPSE and worse TAPSE/RVSP ratio than controls. Also, RA-patients with mild ePH had reduced right ventricular-pulmonary arterial coupling in comparison with patients with RA and normal RVSP. These echocardiographic findings could justify aggressive treatment for these patients and assess their evolution. Key Points • Right ventricular (RV) function and RV coupling with the pulmonary artery (RV-PA coupling) were worse in patients with RA in comparison to healthy controls. • Values of right ventricular systolic pressure (RVSP) were similar between RA-patients and non-RA controls. • Prevalence of normal RVSP, mild echocardiographic pulmonary hypertension (ePH), and pulmonary hypertension was similar between RA-patients and non-RA matched controls •Patients with RA and mild ePH had reduced RV-PA coupling in comparison with RA-patients with normal RVSP.

Prognostic Value of Cardiac Magnetic Resonance-Derived Right Ventricular Remodeling Parameters in Pulmonary Hypertension: A Systematic Review and Meta-Analysis.

Background Cardiac right ventricular remodeling plays a substantial role in pathogenesis, progression, and prognosis of pulmonary hypertension. Cardiac magnetic resonance is considered an excellent tool for evaluation of right ventricle. However, value of right ventricular remodeling parameters derived from cardiac magnetic resonance in predicting adverse events is controversial. Methods The Pubmed (MEDLINE), Embase, Cochrane Library, Web of Science, China National Knowledge Infrastructure platform (CNKI), China Science and Technology Journal Database (VIP), and Wanfang databases were systematically searched until November 2019. Studies reporting hazard ratios (HRs) for all-cause death and composite end point of pulmonary hypertension were included. Univariate HRs were extracted from the included studies to calculate pooled HRs of each right ventricular remodeling parameter. Results Eight studies with 1120 patients examining all-cause death (female: 44%-92%, age: 40-67 years old, follow-up time: 27-48 months) and 10 studies with 604 patients examining composite end point (female: 60%-83%, age: 29-57 years old, follow-up time: 10-68 months) met the criteria. Right ventricular ejection fraction was the only parameter which could predict both all-cause death (pooled HR=0.95; P=0.014) and composite end point (pooled HR=0.95; P<0.001), although right ventricular end-diastolic volume index (pooled HR=1.01; P<0.001), right ventricular end-systolic volume index (pooled HR=1.01, P=0.045), and right ventricular mass index (pooled HR=1.03, P=0.032) only predicted composite outcome. Similar results were observed when we conducted the meta-analysis among patients with World Health Organization type I of pulmonary hypertension. Conclusions Cardiac magnetic resonance-derived right ventricular remodeling parameters have independent prognostic value for all-cause death and composite end point of patients with pulmonary hypertension. Right ventricular ejection fraction was the strongest prognostic factor among all the right ventricular remodeling parameters. Right ventricular mass index, right ventricular end-diastolic volume index, and right ventricular end-systolic volume index also demonstrated prognostic value.

544 Deep learning in segmentation and function evaluation of right ventricle in 2D echocardiography

Abstract INTRODUCTION Deep learning (DL) has been of increasing use in the field of echocardiographic cardiology. The importance of segmentation and recognition of different heart chambers was already presented in different studies. However, there are no studies made regarding the functional heart measurements. Even though, functional measurements of right ventricle (RV) remains "dark side of the moon", no doubtfully severity of RV dysfunction influences the worse outcomes. PURPOSE To evaluate DL for recognition of geometrical features of RV and measurement of RV fractional area change (FAC). METHODS A total of 896 end-systolic and end-diastolic frames from 129 patients (with various indications for the study) were used to train and validate the neural networks. Raw pixel data was extracted from EPIQ 7G (Philips) imaging platform. All of the images were from 2D echocardiography apical four chamber views. RV was annotated in each image, with 1716 images used for training and 180 for validation. We used the state of art mask regional convolutional neural network (MR-CNN) and attention U-net convolutional neural network models for the RV segmentation task. Intersection over Union (IoU) was used as the primary metric for model evaluation. IoU measures the number of pixels common between the target and the prediction masks divided by the total number of pixels present across both masks. Additionally FAC was calculated using frames with minimal and maximal segmented area by the network. RESULTS U-Net architecture demonstrated considerably faster training compared to MR-CNN with time per training step of 85 ms and 750 ms for U-Net and MR-CNN, respectively (p &amp;lt; 0.001). MR-CNN and U-Net had an IoU of 0.91 and 0.89 respectively on validation dataset which corresponds to good performance of the model and there was no significant difference between the different neural networks (p = 0.876). Comparing the evaluation of FAC by physician and U-Net the mean squared difference was 12% when using minimum and maximum right ventricle area detected by the network. CONCLUSION With small dataset deep learning give us ability to recognize RV and measure RV FAC in apical four chamber view with high accuracy. This method offers assessment of RV to become daily used in the cardiologist practice, moreover, in the near future automated measurements will allow to reduce the need of observer manual evaluation. Improvements can be made in FAC calculation by also improving techniques for end-systolic and end-diastolic frame detection.

Early failure of tricuspid annuloplasty. Should we repair the tricuspid valve at an earlier stage? The role of right ventricle and tricuspid apparatus.

We sought to identify subgroups of patients at a higher probability of tricuspid annuloplasty (TAP) failure early after surgery. From May 2009 to December 2015, 688 patients undergoing TAP for functional tricuspid regurgitation (FTR) at a single institution were included in the study. In all patients, a complete transthoracic echocardiographic evaluation of right ventricle (RV) and tricuspid valve (TV) apparatus was collected. Twenty-six patients (3.8%) died within the first 30 days of surgery. Residual TR after TAP was recorded in 85 (12.4%), moderate in 80 (11.7%) and severe in 5 (0.7%). Preoperative TV apparatus remodeling was associated with residual TR; in particular, the following cutoffs were identified: TV coaptation depth ≥6.5 mm, tenting area ≥0.85 cm2 , and tricuspid annulus ≥35 mm. The entire cohort was stratified in three subsets: patients having preoperative mild/moderate TR without preoperative TV apparatus and/or RV remodeling (n = 178); patients having mild/moderate TR with TV apparatus and/or RV remodeling (n = 317); patients with severe TR regardless of TV apparatus and/or RV remodeling (n = 193). Residual TR was 2.8%, 10.4%, and 24.3%, respectively (P < 0.001). At multivariable analysis, patients showing preoperative mild/moderate TR with TV apparatus and/or RV remodeling as well as patients with severe TR were at significantly higher risk for early failure. No difference was found regarding the type of TV repair performed. Prophylactic TAP should be encouraged among surgeons even earlier than guidelines recommend, and decision-making for the treatment of low-grade FTR at the time of left-sided valve surgery should take into consideration not only annular size but also tethering severity and RV dilatation.

Echocardiographic assessment of right ventricular function in experimental pulmonary hypertension.

Echocardiography, a non-invasive and cost-effective method for monitoring cardiac function, is commonly used for evaluation and pre-clinical diagnostics of pulmonary hypertension (PH). Previous echocardiographic studies in experimental models of PH are fragmentary in terms of the evaluation of right ventricle (RV) function. In this study, three rodent models of PH: a mouse model of hypoxia-induced PH, a rat model of hypoxia+Sugen induced PH and a rat model of monocrotaline-induced PH, were employed to measure RV fractional area change (RVFAC), RV free wall thickness (RVFWT), pulmonary acceleration time (PAT), pulmonary ejection time (PET), and tricuspid annular plane systolic excursion (TAPSE). We found that, in these models, RVFWT significantly increased, but RVFAC, PAT, or PAT/PET ratios and TAPSE values significantly decreased. Accurate and complete TAPSE patterns were demonstrated in the three rodent models of PH. The RV echocardiography data matched the corresponding invasive hemodynamic and heart histologic data in each model. This serves as a reference study for real-time and non-invasive evaluation of RV function in rodent models of PH using echocardiography.

Diagnostic modality for evaluation of right ventricle in chronic thromboembolic pulmonary hypertension patients

Background: Chronic thromboembolic pulmonary hypertension (CTEPH) is a progressive disease of pulmonary hypertension (PH) as a consequence obstructive of pulmonary arteries with thromboembolism. Augmented pulmonary vascular resistance and pulmonary artery pressure (PAP) can ultimately lead to the right ventricular dysfunction, which leads to adaptive and maladaptive changes. Right ventricle (RV) remodeling can cause clinical deterioration and RV failure. Aims and Objectives: We aimed to evaluate the RV functions with a new diagnostic modality 2-deoxy-2-(18F)-fluoro-D-glucose (FDG)-positron emission tomography (PET) in patients with CTEPH. Materials and Methods: We included 53 patients diagnosed with CTEPH who were planned to have pulmonary thromboendarterectomy (PEA) and did not have any contraindication for cardiac PET/computed tomography (CT). We performed transthoracic echo, cardiac PET/CT, 6-minute walk distance (6-MWT), and right heart catheterization 1 week before PEA surgery. Results: The patients divided into two groups according to RV/left ventricle (LV) FDG-PET uptake ratio, RV/LV ≤1, and RV/LV >1. Six-MWD was significantly higher in the RV/LV ≤1 group (P = 0.005). Pro-BNP was considerably higher in the RV/LV >1 group (P = 0.041). Conclusion: The present study aims to demonstrate the RV/LV FDG-PET uptake ratio could be used in the noninvasive diagnostic method in diagnosing, treatment strategy, and clinical follow-up in patients with CTEPH.

NUCLEAR IMAGING IN PULMONARY HYPERTENSION

The review describes current possibilities of nuclear imaging methods in different types of pulmonary hypertension (PH): lung ventilation-perfusion scintigraphy and single photon emission computed tomography (SPECT), radionuclide ventriculography and angiography, as well as new potentials of myocardial perfusion SPECT for the evaluation of right ventricle.

Value of ECV quantification in PAH: correlation with echocardiographic, MRI and serum biomarkers

Background The evaluation of right ventricle (RV) function is paramount in pulmonary hypertension (PAH) although it can be difficult to assess. Right ventricular myocardial fibrosis assessed using late gadolinium enhancement (LGE) has been correlated with right ventricular function and prognosis. Myocardial fibrosis can be evaluated by several methods, including LGE, ECV quantification using native and post contrast T1 mapping sequence and serum markers of collagen turnover. Value of ECV quantification and it’s correlation with other biomarkers has not been systematically assessed during PAH. The goal of that study is to compare ECV, echo longitudinal strain, and serum markers of collagen turnover in the assessment of myocardial fibrosis in a population of adults with PAH.

Right Ventricular Dimensions and Function: Why do we Need a More Accurate and Quantitative Imaging?

The right ventricle plays an important role in the morbidity and mortality of patients presenting with symptoms and signs of cardiopulmonary disease. This cardiac chamber has a unique crescent shape, which adds complexity to the quantification of its size and function. Until recently, little uniformity in echocardiographic imaging of the right heart existed because of a lack of familiarity with various techniques, and the enormous attention directed towards left heart quantification. Three-dimensional (3D) echocardiography, a major technological breakthrough in the field of cardiovascular imaging, provides several advantages over two-dimensional (2D) imaging in the quantitative evaluations of right ventricle because of its independence from any geometrical assumption. In this review, we focus on the contribution of this new modality to the evaluation of right ventricle.

Evaluation of right ventricle by speckle tracking and conventional echocardiography in rats with right ventricular heart failure.

Speckle tracking echocardiography (STE) has been reported to be a promising technique for evaluating right ventricular (RV) function in the clinical setting. On the other hand, the usefulness of STE for RV evaluation in small animal models has not been clarified, although the rat model is among the most commonly used animal models to develop novel effective treatments against pulmonary hypertension and RV heart failure (HF).We validated the use of STE and conventional echocardiographic variables for evaluating RV functions in a rat model by comparing the echocardiographic values of RVHF rats (n = 12) induced by monocrotaline injection with those of control rats (n = 12).Most conventional echocardiographic variables demonstrated that RVHF rats have significant RV dysfunction. The area under the curve (AUC) values to distinguish RV dysfunction in RVHF rats from normal RV function in control rats using fractional area change (FAC), tricuspid annular plane systolic excursion (TAPSE), RV myocardial performance index (MPI), peak tissue Doppler tricuspid annular velocities at systole (Sa), and at early diastole (Ea) were 0.71, 0.98, 0.79, 0.92, and 0.91, respectively. However, using STE analysis for RV evaluation, limited reproducibility was observed (variability 19-37 %, ICC 0.74-0.88) and the only circumferential strain showed significantly lower absolute values (P = 0.039, AUC = 0.76).To evaluate RV function in rat models, circumferential strain may be useful, however, the reproducibility and diagnostic utility were limited. Conventional echocardiographic variables such as TAPSE, tissue Doppler Sa, and Ea have superior diagnostic utility.

Evaluation of right ventricle with echocardiography: Utility of combined techniques

Evaluation of right ventricle with echocardiography: Utility of combined techniques

Efficiency and reproducibility of the right ventricular long axis imaging plane for the evaluation of right ventricle

Methods Thirty-four clinical cardiac MRI exams that contained two cine bFFE stacks one in the SAX orientation, the second aligned with the horizontal long axis of the RV (RVHLA) were evaluated. Two radiologists independently derived RV volumes on each of these two cine stacks of images for the 34 exams. Readers recorded the number of slices needed and the time required to manually draw the endocardial contours to perform the RV functional analysis for each cine stack. The resulting RV functional metrics obtained included the end diastolic volume (EDV), end systolic volume (ESV), and ejection fraction (EF). The number of slices, analysis time, and the RV metrics were then compared between readers and between imaging planes (SAX vs RVHLA).

Reply from Zeljko Dujic

After careful reading of the Letter by Dr Marabotti and colleagues we agree with the major part of the critique of the method that is employed for evaluation of the right heart. Although we were aware of the other methods that are available we had several constraints that prevented us from using them. Fist, we decided to perform a field study. In some of our previous experiments we carried out simulated diving studies and found that diving in a hyperbaric chamber produces less venous gas bubbles than diving in real conditions. However maximal amount of venous bubbles occurred around 40 min after surfacing, which prevented us from using any equipment beside a transportable ultrasound device. We needed to perform measurements on multiple time points after dive, and tested divers are very reluctant to undergo invasive procedures. Although, radionuclide angiography is still considered the most reliable method for evaluating right ventricular volumes and function, the current literature shows no data to suggest that one method is an obligatory golden standard for volumetric evaluation of right ventricle, and most of the methods that are now widely used for estimation of volume and performance of right ventricle are semiquantitative (Kovalova, 2005). Volumetric measurements of the right heart represented only one of the observed parameters, and in all cases we were looking for the relative changes in the same subject. However, the point that has been made in the Letter is correct, and it may be that the best way to interpret these results would be to represent them as relative numbers since this was the main goal of this part of investigation. In our further studies we shall try to implement 3D and 4D volumetric quantification of left and right cavities both for absolute and relative numbers.

438 Value of NT-pro BNP and Tei index for the evaluation of right ventricle after repair of Tetralogy of Fallot

438 Value of NT-pro BNP and Tei index for the evaluation of right ventricle after repair of Tetralogy of Fallot

Isolated right ventricular infarction in a case of hypertrophic cardiomyopathy

A case of isolated right ventricular infarction in a young female with hypertrophic cardiomyopathy is reported. This case highlights the importance of detailed evaluation of right ventricle in cases with hypertrophic cardiomyopathy.