Changes In Right Ventricular Volumes Research Articles

Three dimensional speckle tracking echocardiography in breast cancer patients receiving chemotherapy: incidence and clinical outcomes of subclinical right ventricular systolic dysfunction

Abstract Background The data about the influence of chemotherapy on right ventricular (RV) function and mechanics are scarce and conflicting. Due to the special geometric structure and unique wall motion of the RV, routine techniques for echocardiographic assessment of the RV has challenges. However, 3-dimensional echocardiography (3DE) tracks changes in RV volumes in real time, including the inflow and outflow tracts and the apex throughout the cardiac cycle. 3DE evaluation of RV function and morphology has been compared to cardiac magnetic resonance and is accurate, feasible, and reproducible Methods This study conducted was a retrospective cohort study which included 75 breast cancer patients who underwent chemotherapy at a tertiary hospital from January 2019 to May 2021 to determine clinical outcomes of patients among those who developed an abnormal right ventricular longitudinal free wall strain and global longitudinal strain in terms of all-cause mortality, development of overt right ventricular systolic dysfunction, and adverse cardiovascular events. Results There was a striking statistically significant difference in terms of right ventricular ejection fraction among those who developed an abnormal right ventricular global longitudinal strain at 6 and 12 months post-chemotherapy with a p-value of 0.001 and 0.000 respectively. The difference between the 2 groups of patients in terms of right ventricular global longitudinal strain 6 and 12 months after chemotherapy was also statistically significant (p=0.000). As for the left ventricle, the LV ejection fraction and global longitudinal strain were also statistically significantly different at 12 months post-chemotherapy. Among those who developed an abnormal RV global longitudinal strain, the LV global longitudinal strain was also subsequently lower compared to the normal subgroup at 12 months post-treatment. Conclusion Although the sample size was small, the development of abnormal RV GLS post-chemotherapy was generally associated with subsequent development of overt heart failure, increased all-cause mortality, and CV death. The use of echocardiographic RV GLS surveillance to guide chemotherapy is crucial to enhance clinical outcomes and survival. Funding Acknowledgement Type of funding sources: None.

Clinically important changes in right ventricular volume and function in pulmonary arterial hypertension assessed with cardiac magnetic resonance imaging.

Right ventricular (RV) dilatation predicts clinical worsening in pulmonary arterial hypertension (PAH) and RV volumes can be measured with high precision using cardiovascular magnetic resonance imaging. In regular follow‐up of patients and in studies of improvement in RV function, knowledge of clinically significant changes of RV volumes and function are of relevance. Patients with PAH were followed with cardiovascular magnetic resonance imaging and clinical assessment at 6‐month intervals. Changes in RV volumes associated with changes in clinical status were assessed. Twenty‐five patients with PAH (Group 1) were included and examined every 6 months for 2.5 years, with a total of 107 MRI scans. For a step change in WHO functional class, the associated change in RV volume was 11% (confidence interval 7%−14%, p < 0.0001) and in stroke volume 9% (confidence interval 3%−15%, p = 0.003). This study found an 11% change in RV volume to be clinically significant. The combination of clinically significant changes and the known precision in the measurements enables individualized follow‐up of RV‐function in PAH. To our knowledge, this study is the first to use repeated assessments to suggest clinically significant changes of RV volume based on changes in clinical presentation.

Changes in Right Ventricular Volume, Volume Load, and Function Measured with Cardiac Computed Tomography over the Entire Time Course of Tetralogy of Fallot.

ObjectiveTo characterize the changes in right ventricular (RV) volume, volume load, and function measured with cardiac computed tomography (CT) over the entire time course of tetralogy of Fallot (TOF).Materials and MethodsIn 374 patients with TOF, the ventricular volume, ventricular function, and RV volume load were measured with cardiac CT preoperatively (stage 1), after palliative operation (stage 2), after total surgical repair (stage 3), or after pulmonary valve replacement (PVR) (stage 4). The CT-measured variables were compared among the four stages. After total surgical repair, the postoperative duration (POD) and the CT-measured variables were correlated with each other. In addition, the demographic and CT-measured variables in the early postoperative groups were compared with those in the late postoperative and the preoperative group.ResultsSignificantly different CT-based measures were found between stages 1 and 3 (indexed RV end-diastolic volume [EDV], 63.6 ± 15.2 mL/m2 vs. 147.0 ± 38.5 mL/m2 and indexed stroke volume (SV) difference, 7.7 ± 10.3 mL/m2 vs. 32.2 ± 16.4 mL/m2; p < 0.001), and between stages 2 and 3 (indexed RV EDV, 72.4 ± 19.7 mL/m2 vs. 147.0 ± 38.5 mL/m2 and indexed SV difference, 5.7 ± 13.1 mL/m2 vs. 32.2 ± 16.4 mL/m2; p < 0.001). After PVR, the effect of RV volume load (i.e., indexed SV difference) was reduced from 32.2 mL/m2 to 1.7 mL/m2. Positive (0.2 to 0.8) or negative (−0.2 to −0.4) correlations were found among the CT-based measures except between the RV ejection fraction (EF) and the RV volume load parameters. With increasing POD, an early rapid increase was followed by a slow increase and a plateau in the indexed ventricular volumes and the RV volume load parameters. Compared with the preoperative data, larger ventricular volumes and lower EFs were observed in the early postoperative period.ConclusionCardiac CT can be used to characterize RV volume, volume load, and function over the entire time course of TOF.

The change of QRS duration after pulmonary valve replacement in patients with repaired tetralogy of Fallot and pulmonary regurgitation.

PurposeThis study aimed to analyze changes in QRS duration and cardiothoracic ratio (CTR) following pulmonary valve replacement (PVR) in patients with tetralogy of Fallot (TOF).MethodsChildren and adolescents who had previously undergone total repair for TOF (n=67; median age, 16 years) who required elective PVR for pulmonary regurgitation and/or right ventricular out tract obstruction were included in this study. The QRS duration and CTR were measured pre- and postoperatively and postoperative changes were evaluated.ResultsFollowing PVR, the CTR significantly decreased (pre-PVR 57.2%±6.2%, post-PVR 53.8%±5.5%, P=0.002). The postoperative QRS duration showed a tendency to decrease (pre-PVR 162.7±26.4 msec, post-PVR 156.4±24.4 msec, P=0.124). QRS duration was greater than 180 msec in 6 patients prior to PVR. Of these, 5 patients showed a decrease in QRS duration following PVR; QRS duration was less than 180 msec in 2 patients, and QRS duration remained greater than 180 msec in 3 patients, including 2 patients with diffuse postoperative right ventricular outflow tract hypokinesis. Six patients had coexisting arrhythmias before PVR; 2 patients, atrial tachycardia; 3 patients, premature ventricular contraction; and 1 patient, premature atrial contraction. None of the patients presented with arrhythmia following PVR.ConclusionThe CTR and QRS duration reduced following PVR. However, QRS duration may not decrease below 180 msec after PVR, particularly in patients with right ventricular outflow tract hypokinesis. The CTR and ECG may provide additional clinical information on changes in right ventricular volume and/or pressure in these patients.

Progressive right ventricular enlargement due to pulmonary regurgitation: Clinical characteristics of a “low-risk” group

BackgroundThe optimal interval between serial cardiac magnetic resonance imaging (CMRI) scans for monitoring right ventricular (RV) enlargement in the setting of severe pulmonic valve regurgitation (PR) is unknown. The purposes of this study were to (1) determine the annual change in RV volume on serial CMRI scans and (2) identify the risk factors for rapid progression of RV enlargement. MethodsA retrospective study of adults with postintervention native valve PR and ≥2 CMRI scans at Mayo Clinic Rochester from 2000 to 2015 was conducted. Rapid progression of RV enlargement was defined as first upper quartile of annual increase in RV end-diastolic volume index (RVEDVi) for the cohort. ResultsOf the 63 patients (age, 36 ± 9 years) in the study, 43 (68%) had tetralogy of Fallot, whereas 20 (32%) had valvular pulmonic stenosis. Right ventricular outflow tract interventions that resulted in PR were balloon pulmonary valvuloplasty (n = 4; 7%), transannular patch repair (n = 30; 58%), and nontransannular patch repair (n = 18; 35%). Interval between baseline and second CMRI was 2 (1-4) years. In comparison to baseline CMRI, RVEDVi increased from 130 (109-141) to 135 (126-155) mL/m2 and median annual change in RVEDVi was 3.1 (1.7-5.9) mL/m2. Univariate risk factors for rapid progression of RV enlargement (annual increase in RVEDVi >6 mL/m2) were ≥moderate tricuspid regurgitation and RVEDVi >130 mL/m2. Among the 24 patients without these risk factors (low-risk subgroup), RVEDVi increased by only 3 (0-7) mL/m2 over 7 (5-9) years. ConclusionsPatients with PR without RVEDVi >130 mL/m2 and/or ≥moderate tricuspid regurgitation represent a low-risk subgroup that may be appropriate for clinical and echo follow-up but may potentially require infrequent CMRI follow-up.

Subclinical changes in MRI-determined right ventricular volumes and function in subjects with prediabetes and diabetes.

The aim of this study was to assess subclinical changes in right ventricular volumes and function in subjects with prediabetes and diabetes and controls without a history of cardiovascular disease. Data from 400 participants in the KORA FF4 study without self-reported cardiovascular disease who underwent 3-T whole-body MRI were obtained. The right ventricle was evaluated using the short axis and a four-chamber view. Diabetes was defined according to WHO criteria. Associations between glucose tolerance and right ventricular parameters were assessed using multivariable adjusted linear regression models. Data from 337 participants were available for analysis. Of these, 43 (13%) had diabetes, 87 (26%) had prediabetes, and 207 (61%) were normoglycaemic controls. There was a stepwise decrease in right ventricular volumes in men with prediabetes and diabetes in comparison with controls, including right ventricular end-diastolic volume (β = -20.4 and β = -25.6, respectively; p ≤ 0.005), right ventricular end-systolic volume (β = -12.3 and β = -12.7, respectively; p ≤ 0.037) and right ventricular stroke volume (β = -8.1 and β = -13.1, respectively, p ≤ 0.016). We did not observe any association between prediabetes or diabetes and right ventricular volumes in women or between prediabetes or diabetes and right ventricular ejection fraction in men and women. This study points towards early subclinical changes in right ventricular volumes in men with diabetes and prediabetes. • MRI was used to detect subclinical changes in right ventricular parameters. • Diabetes mellitus is associated with right ventricular dysfunction. • Impairment of right ventricular volumes seems to occur predominantly in men.

Change in Right Ventricular Volume and Function After Pulmonary Valve Replacement

Change in Right Ventricular Volume and Function After Pulmonary Valve Replacement

The effects of pulmonary vasodilating agents on right ventricular parameters in severe group 3 pulmonary hypertension: a pilot study.

Pulmonary arterial hypertension (PAH)-approved vasodilators improve right ventricular (RV) function in patients with PAH. However, whether PAH-approved drugs ameliorate RV morphology and function in lung disease-associated pulmonary hypertension (lung-PH) remains unclear. We aimed to prospectively evaluate the changes in RV volume and ejection fraction (RVEF) in 14 consecutive severe lung-PH patients treated with PAH-approved vasodilators. Severe lung-PH was defined as a mean pulmonary arterial pressure (MPAP) of ≥35 mmHg or an MPAP of ≥25 mmHg with a cardiac index (L/min/m2) of <2. Right heart catheterization and cardiac magnetic resonance (CMR) imaging were performed at baseline and at 3 months after starting sildenafil with or without other PAH-approved drugs. Follow-up was conducted at 3 months in 11 participants; compared with baseline values, MPAP and pulmonary vascular resistance (PVR) decreased by 18% and 37%, respectively. Baseline CMR imaging revealed an elevated RV end-diastolic volume index (RVEDVI; mL/m2) of 117.5 ± 35.9 and a below-average RVEF of 25.2% ± 7.2%; after 3 months, RVEDVI decreased by 23.7% (P = 0.0061) and RVEF increased by 32.9% (P = 0.0165). Among the 11 patients, 3 were thought to be a stable and homogenous subset in terms of background lung disease and medical management administered. These 3 patients exhibited similar ameliorations in PVR and RVEF, compared with the other 8 patients. PAH-approved drug treatment may improve RV dilatation and systolic function among patients with severe lung-PH. This study was approved by University Hospital Medical Information Network Clinical Trials Registry (UMIN-CTR) on September 1, 2013 (UMIN000011541).

Brugada syndrome: clinical presentation and genotype-correlation with magnetic resonance imaging parameters.

The purpose of the this study was to evaluate a possible genotype-phenotype correlation in BrS patients and to analyze possible associations with clinical events in affected patients. SCN5A gene encodes the alpha-subunit of the voltage-gated sodium channel NaV1.5. Its mutations are associated with a broad spectrum of hereditary arrhythmias such as long-QT syndrome, cardiac conduction diseases, and Brugada syndrome (BrS). Experimental studies have shown an interaction between SCN5A and cellular cytoskeleton, explaining its functional role in cellular integrity of heart cells. Cardiovascular magnetic resonance was performed on 81 consecutive genetically screened BrS patients and 30 healthy controls. Left ventricular (LV) and right ventricular (RV) volumes and dimensions were assessed and compared with respect to the genotype. Brugada syndrome patients with an SCN5A mutation (16 patients; 20%) revealed significantly larger RV volumes, along with lower RV ejection fraction, than patients without a mutation or controls, indicating a more severe phenotype in patients with a mutation. Furthermore, patients with an SCN5A mutation showed significantly more often a spontaneous type 1 BrS-electrocardiogram (ECG). In multivariate analysis, the presence of a spontaneous type 1 BrS-ECG showed the strongest association with cardiac events. Receiver-operating characteristic curve analysis indicated good predictive performance of RV end-diastolic volume, RV end-systolic, and LV cardiac output (area under the curve = 0.81, 0.81, and 0.2), with respect to the presence of an SCN5A mutation. Brugada syndrome patients with an SCN5A mutation reveal distinct changes in RV volumes and function when compared with those without an SCN5A mutation. Furthermore, mutation-positive patients have a higher likelihood of a spontaneous type 1 BrS-ECG, which is associated with a higher incidence of clinical events. Cardiovascular magnetic resonance may provide additional insight to distinguish between SCN5A mutation-positive and -negative BrS patients.

Signs of Right Ventricular Deterioration in Clinically Stable Patients With Pulmonary Arterial Hypertension

BACKGROUND: Even after years of stable response to therapy, patients with idiopathic pulmonary arterial hypertension (IPAH) may show an unexpected clinical deterioration due to progressive right ventricular (RV) failure. Therefore, the aim of this study was to assess in 5-year clinically stable patients with IPAH whether initial differences or subsequent changes in RV volumes precede late clinical progression.METHODS: Included were 22 clinically stable patients with IPAH as reflected by stable or improving New York Heart Association functional class II-III and exercise capacity during 5 years of follow-up. Twelve patients subsequently remained stable during a total follow-up of 10 years, whereas 10 other patients showed late progression leading to death or lung transplantation after a follow-up of 8 years. All patients underwent right-sided heart catheterization and cardiac MRI at baseline and at 1½, 3½, 6½, and, if still alive, 10 years follow-up.RESULTS: Baseline hemodynamics were comparable in both groups and remained unchanged during the entire follow-up period. Baseline RV end-systolic volume (RVESV) was higher and RV ejection fraction (RVEF) was lower in late-progressive patients. Late-progressive patients demonstrated a gradually increased RV end-diastolic volume and RVESV and a decline in RVEF, whereas long-term stable patients did not show any RV changes.CONCLUSIONS: In patients with stable IPAH for 5 years, subsequent late disease progression is preceded by changes in RV volumes. The results indicate that monitoring RV volumes anticipates clinical worsening, even at a time of apparent clinical stability.

Right ventricular reverse remodelling after balloon pulmonary angioplasty

Balloon pulmonary angioplasty (BPA) has been reported to improve haemodynamics and functional capacity, with an acceptable risk, in patients with chronic thromboembolic pulmonary hypertension (CTEPH) who are not candidates for pulmonary endarterectomy. However, right ventricular (RV) function, an important predictor in CTEPH, remains to be elucidated. We aimed to examine the impact of BPA on RV remodelling and dysfunction relative to haemodynamic improvements in patients with inoperable CTEPH. 20 consecutive patients with inoperable CTEPH who underwent BPA with cardiovascular magnetic resonance before and after BPA were retrospectively studied. BPA led to significant amelioration of the mean pulmonary arterial pressure, cardiac index and pulmonary vascular resistance (PVR), without death or major complications. Furthermore, BPA significantly ameliorated right-sided heart failure symptoms and signs, and exercise capacity. Cardiovascular magnetic resonance revealed a marked improvement in RV end-diastolic and end-systolic volume index, with concomitant improvements in RV ejection fraction, mass and interventricular septal bowing after BPA. Changes in RV volumes strongly correlated with changes in cardiac index and PVR. BPA induced RV reverse remodelling and improved systolic dysfunction safely by ameliorating haemodynamics in patients with inoperable CTEPH. Evaluating RV function with cardiovascular magnetic resonance may be effective for noninvasively monitoring BPA efficacy.

Prognostic value of clinical, morphological and genetic findings in Brugada patients: a prospective CMR study

Background: SCN5A gene encodes the alpha-subunit of the voltage-gated sodium channel Nav1.5. Accordingly, its mutations are associated with a broad spectrum of hereditary arrhythmias like long QT syndrome, cardiac conduction diseases or Brugada syndrome. Genetic screening for a SCN5A mutation is increasingly being used in patients with Brugada syndrome presenting with a typical type-1 ECG. Objectives: The purpose of this study was to elucidate a possible genotype-phenotype correlation in patients with Brugada syndrome (BrS) and to analyze predictors for clinical events in affected patients. Methods: CMR was performed on 81 consecutive patients with proven BrS and 30 healthy controls. 38 patients had a spontaneous diagnostic type-1 BrS-ECG; 43 patients expressed the type-1 ECG only in response to ajmaline challenge. Left- and right ventricular volumes and dimensions were assessed and compared with respect to the ECG pattern. All Brugada patients were genetically screened for a mutation of the SCN5A gene. Results: Out of 81 Brugada patients, 16 (20%) were diagnosed with a mutation of the SCN5A gene while 5 patients (6%) expressed the mutation in the calcium channel coding genes CACNA1C and CACNB2B. 60 patients (74%) had no known mutation. Patients diagnosed with a mutation showed significantly more often a spontaneous Brugada type-1 pattern (69% vs. 39%, p=0.03). Furthermore, MRI scans revealed increased right ventricular end-diastolic and end-systolic volumes, along with a significant decrease in right ventricular output (4.4 l/min vs. 5.5 l/min, p=0.01) and right ventricular ejection fraction (51.7% vs. 55.5%, p=0.02), indicating a more severe phenotype in patients bearing a mutation. Univariate analysis showed that the presence of a SCN5A mutation increases the likelihood of a spontaneous type-1 BrS-ECG pattern (OR 3.4; CI 1.1-11.3) compared to patients without a mutation. In multivariate analysis however, the presence of a SCN5A, did not add clinical value in prediction of syncope or sudden cardiac death. In our analysis, the presence of a spontaneous type-1 ECG was the strongest predictor for cardiac events. Conclusions: Brugada patients with a SCN5A mutation reveal distinct changes in right ventricular volumes, and a significant decrease of right ventricular function as compared to those without a SCN5A mutation. Furthermore, SCN5A-mutation positive patients have a higher likelihood of a spontaneous type-1 ECG, which is associated with a higher incidence of clinical events, such as syncope or sudden cardiac death.

Enlarged right-sided dimensions and fibrosis of the right ventricular insertion point on cardiovascular magnetic resonance imaging is seen early in patients with pulmonary arterial hypertension associated with connective tissue disease

Objectives: To describe the findings of cardiovascular magnetic resonance (CMR) imaging in patients with pulmonary arterial hypertension (PAH) associated with connective tissue disease (CTD) and in consecutive patients with systemic sclerosis (SSc) without PAH.Methods: The study comprised nine consecutive patients who were admitted for right heart catheterization (RHC) under a suspicion of CTD-PAH and 25 consecutive patients who were admitted for evaluation because of a clinical suspicion of SSc. In addition to the regular assessment, they also underwent examination by CMR.Results: CMR measurements of right ventricular (RV) volumes and function showed severe pathology in patients with CTD-PAH. Patients with SSc without PAH had similar but much less severe findings. Right ventricular end-diastolic volume (RVEDV) and right ventricular ejection fraction (RVEF) were abnormal in all patients with CTD-PAH. In eight out of nine patients with CTD-PAH, fibrosis was seen in the RV insertion point, probably caused by increased tension, but only in one of the consecutive SSc patients. This patient was diagnosed with CTD-PAH 20 months later.Conclusions: In CTD-PAH, CMR shows severe changes in RV volumes and function, but also fibrosis in the RV insertion point. Similar abnormalities, although much less severe, may be seen at diagnosis of SSc. Further evaluation is warranted to determine whether these findings are of value in screening for early signs of PAH in SSc.

Preoperative Thresholds for Pulmonary Valve Replacement in Patients With Corrected Tetralogy of Fallot Using Cardiovascular Magnetic Resonance

To facilitate the optimal timing of pulmonary valve replacement, we analyzed preoperative thresholds of right ventricular (RV) volumes above which no decrease or normalization of RV size takes place after surgery. Between 1993 and 2006, 71 adult patients with corrected tetralogy of Fallot underwent pulmonary valve replacement in a nationwide, prospective follow-up study. Patients were evaluated with cardiovascular magnetic resonance both preoperatively and postoperatively. Changes in RV volumes were expressed as relative change from baseline. RV volumes decreased with a mean of 28%. RV ejection fraction did not change significantly after surgery (from 42+/-10% to 43+/-10%; P=0.34). Concomitant RV outflow tract reduction resulted in a 25% larger decrease of RV volumes. After correction for surgical RV outflow tract reduction, higher preoperative RV volumes (mL/m2) were independently associated with a larger decrease of RV volumes (RV end-diastolic volume: beta=0.41; P<0.001). Receiver operating characteristic analysis revealed a cutoff value of 160 mL/m2 for normalization of RV end-diastolic volume or 82 mL/m2 for RV end-systolic volume. Overall, we could not find a threshold above which RV volumes did not decrease after surgery. Preoperative RV volumes were independently associated with RV remodeling and also when corrected for a surgical reduction of the RV outflow tract. However, normalization could be achieved when preoperative RV end-diastolic volume was <160 mL/m2 or RV end-systolic volume was <82 mL/m2.

Time course of right ventricular remodeling in rats with experimental myocardial infarction.

Right ventricular (RV) weight increases dependent on time after myocardial infarction (MI) and on MI size. The sequential changes in RV volume and hemodynamics and their relations to left ventricular (LV) remodeling after MI are unknown. We therefore examined the time course of RV remodeling in rats with LV MI. MI was produced by left coronary artery ligation. Four, eight, and sixteen weeks later, LV and RV hemodynamic measurements were performed and pressure-volume curves were obtained. For serial measurement of RV volumes and performance, cine-MRI was performed 2 and 8 wk after MI. The ratios of beta-myosin heavy chain (MHC) to alpha-MHC and skeletal to cardiac alpha-actin were determined for the RV and LV after large MI or sham operation. RV weight increased in rats with MI, as did RV volume. RV pressure-volume curves were shifted toward larger volumes 16 wk after large MI. RV systolic pressure increased gradually over time; however, the gain in RV weight was always in excess of RV systolic pressure. The ratios of skeletal to cardiac alpha-actin and beta-MHC to alpha-MHC were increased after MI in both ventricles in a similar fashion. Because RV wall stress was not increased after infarction, mechanical factors may not conclusively explain hypertrophy, which maintained balanced loading conditions for the RV even after large LV infarction.

Longitudinal motion of the atrioventricular annuli in children: Reference values, growth related changes, and effects of right ventricular volume and pressure overload

The goals of this study were to characterize normal patterns of longitudinal motion of atrioventricular annuli in the young, establish reference values and assess growth-related changes (n = 40). Sensitivity to changes in right ventricular volume and pressure load was assessed in patients with atrial septal defect (ASD) (n = 25) and with primary pulmonary hypertension (PPH) (n = 20). M-mode of the annuli were obtained from apical views. In healthy subjects, longitudinal %displacement decreased with growth, lateral tricuspid annulus had highest %displacement, velocity of annular descent did not change with growth, tricuspid lateral annulus had the highest velocity of descent, only ascent velocity of the lateral tricuspid annulus decreased with growth, velocities of ascent for the lateral annuli were similar and higher than the septum, and heart rate had no effect on parameters tested. In patients with ASD, the findings were an exaggerated normal pattern. In patients with PPH, %displacement and ascent velocities were blunted. Our results demonstrate the utility of this technique to assess annular dynamics in pediatric patients. (J Am Soc Echocardiogr 2002;15:906-16.)

Measurement of right ventricular volume in healthy term and preterm neonates

Background: Pulmonary hypertension is associated with worse perinatal outcomes in infants with respiratory disorders. In such infants right ventricular dysfunction may result in poor pulmonary blood flow. Objective: To evaluate...

Speed of normalization of right ventricular volume overload after transcatheter closure of atrial septal defect in children and adults

Right ventricular (RV) volume overload occurs in patients with significant atrial septal defect (ASD) shunt, which can impair left ventricular (LV) filling and ejection fraction. 1 Louie E.K Lin S.S Reynertson S.I Brundage B.H Levitsky S Rich S Pressure and volume loading of the right ventricle have opposite effects on left ventricular ejection fraction. Circulation. 1995; 92: 819-824 Crossref PubMed Scopus (149) Google Scholar RV dilation and abnormal ventricular septal motion are characteristic echocardiographic features of RV volume overload. Transcatheter closure of secundum ASD was first attempted >25 years ago, and it is being increasingly used in recent years with promising closure results. 2 Rome J.J Keane J.F Perry S.B Spevak P.J Lock J.E Double-umbrella closure of atrial septal defects initial clinical applications. Circulation. 1990; 82: 751-758 Crossref PubMed Scopus (278) Google Scholar , 3 Das G.S Voss G Jarvis G Wyche K Gunther R Wilson R.F Experimental atrial septal defect closure with a new, transcatheter, self-centering device. Circulation. 1993; 88: 1754-1764 Crossref PubMed Scopus (204) Google Scholar , 4 Prieto L.R Foreman C.K Cheatham J.P Latson L.A Intermediate-term outcome of transcatheter secundum atrial septal defect closure using the Bard Clamshell Septal Umbrella. Am J Cardiol. 1996; 78: 1310-1312 Abstract Full Text PDF PubMed Scopus (78) Google Scholar , 5 Rao P.S Berger F Rey C Haddad J Meier B Walsh K.P Chandar J.S Lloyd T.R de Lezo J.S Zamora R Sideris E.B Results of transvenous occlusion of secundum atrial septal defects with the fourth generation buttoned device comparison with first, second and third generation devices. International Buttoned Device Trial Group. J Am Coll Cardiol. 2000; 36: 583-592 Abstract Full Text Full Text PDF PubMed Scopus (83) Google Scholar , 6 Masura J Gavora P Formanek A Hijazi Z.M Transcatheter closure of secundum atrial septal defects using the new self-centering Amplatzer septal occluder initial human experience. Cathet Cardiovasc Diagn. 1997; 42: 388-393 Crossref PubMed Scopus (406) Google Scholar , 7 Thanopoulos B.D Laskari C.V Tsaousis G.S Zarayelyan A Vekiou A Papadopoulos G.S Closure of atrial septal defects with the Amplatzer occlusion device preliminary results. J Am Coll Cardiol. 1998; 31: 1110-1116 Abstract Full Text Full Text PDF PubMed Scopus (258) Google Scholar This study evaluates the change in RV volume overload after transcatheter closure of ASD by echocardiography and assesses the possible influencing factors.

Changes in right ventricular volume in early human neonates

To evaluate changes in the right ventricular volume in early human neonates, twenty fullterm infants were examined at 2, 24 and 120 h of age by two-dimensional echocardiography. End-diastolic and end-systolic right ventricular volumes (RVEDV and RVESV, respectively) were calculated with a computer system based on the bi-plane Simpson's rule using the apical four chamber and parasternal short axis views. Then right ventricular stroke volume (RVSV), ejection fraction (RVEF), and the mean normalized systolic ejection rate were obtained. The inner diameter of the ductus arteriosus was also measured simultaneously. RVEDV increased significantly by 24 h of age, but remained constant thereafter. RVESV remained virtually unchanged from 2 to 120 h, resulting in a significant increase (36%) of RVSV at 24 h compared with that at 2 h. The mean normalized systolic ejection rate remained unchanged. There was a good correlation between RVEDV and RVSV (r = 0.83). All ductus arteriosus except three narrow ones was closed by 24 h of age. In conclusion, at 24 h of age, the significantly increased RVEDV was closely related to the increased RVSV, which might be induced by increased volume load to the right ventricle because of the closure of the ductus arteriosus.

Analysis of right ventricular function during bypass of the left side of the heart by afterload alterations in both normal and failing hearts

This study investigated the mechanism of right ventricular failure during bypass of the left side of the heart by precisely assessing right ventricular function with use of a conductance catheter. Bypass of the left side of the heart was established with a centrifugal pump in 10 mongrel dogs weighing 11 to 19 kg. Right ventricular function during left heart bypass was evaluated by two parameters that were both derived from measurement of relative change in right ventricular volume by the conductance catheter technique. One parameter was the right ventricular end-systolic pressure-volume relationship as a load-independent index, and the other was the peak right ventricular pressure–right ventricular stroke volume relationship as a “force-velocity relationship.” These parameters were measured in both normal and failing hearts while afterload was increased by bilateral intrapulmonary balloon inflation. Moreover, changes in these relationships were observed by varying assist ratios of left heart bypass from 0% to 100%. Failing heart models were induced by normothermic aortic clamping for 20 minutes. The right ventricular end-systolic pressure-volume relationship in normal hearts did not change, irrespective of the assist ratio of left heart bypass, whereas that in failing hearts decreased from 4.25 ± 1.41 mm Hg/ml without bypass of the left side of the heart to 3.53 ± 1.30 mm Hg/ml after 100% assist of left heart bypass ( p < 0.05). In the peak right ventricular pressure–right ventricular stroke volume relationship, right ventricular stroke volume was almost constant in normal hearts when afterload was increased regardless of the assist ratio of left heart bypass. Moreover, right ventricular stroke volume was maintained at a higher level during bypass of the left side of the heart compared with that without left heart bypass. However, that slope of the relationship in failing hearts was inversely linear and became significantly steeper after 100% assist of bypass of the left side of the heart compared with that without left heart bypass (-0.131 ± 0.042 versus -0.051 ± 0.038, p < 0.005). Therefore these two slopes of the relationship intersected at a point that was considered the critical point of afterload during bypass of the left side of the heart. In other words, right ventricular stroke volume was decreased by 100% left heart bypass above the critical point of afterload. In conclusion, this study demonstrates not only that bypass of the left side of the heart results in an increase in right ventricular stroke volume in both normal and failing hearts at the physiologic range of afterload, but also that right ventricular function against higher afterload is impaired by 100% assist of bypass of the left side of the heart in failing hearts.(J T HORAC C ARDIOVASC S URG 1996;111:1092-1102)