Reference Intervals of Fetal Cardiac Volume Between 14 and 40 Weeks of Gestation.

OBJECTIVES: To construct the reference intervals for the cardiac volume (CV) of normal fetuses between 14 and 40 weeks of pregnancy. METHODS: Low risk singleton pregnancies with normal fetuses were prospectively recruited to acquire 4D-cardio-spatiotemporal image correlation volume datasets (VDS). Subsequent off-line analyses of VDS were anonymously performed to calculate CV using the Virtual Organ Computer-aided AnaLysis technique. The reference intervals were established as a function of gestational age (GA), biparietal diameter (BPD), head circumference (HC), and estimated fetal weight (EFW) based on the best-fitted models for both mean and standard deviation (SD). RESULTS: A total of 668 VDS were successfully calculated for CV. The best-fitted models for the means and SDs are as follow: 1) GA in week = 6.422 + e(-100.653 × GA) (SD = 0.641 - (0.170 × GA) + (0.009 × GA2 )). 2) BPD = 0.016 × (BPD)3.589 (SD = 2.663 - (1.410 × BPD) + (0.224 × BPD2 )). 3) HC = 0.00017 × (HC)3.537 (SD = 2.341 - (0.341 × HC) + (0.015 × HC2 )). The CV progressively increased with advancing fetal age (GA) and size (BPD, HC). CONCLUSIONS: The reference intervals of CV, theoretically best representing cardiac size, in relation to GA, BPD, HC, and EFW were first established and Z-score was readily calculated. These will be helpful in detection of cardiac abnormalities, especially those associated with cardiomegaly.

Estimating heart mass from heart volume as measured from post-mortem computed tomography.

Heart mass can be predicted from heart volume as measured from post-mortem computed tomography (PMCT), but with limited accuracy. Although related to heart mass, age, sex, and body dimensions have not been included in previous studies using heart volume to estimate heart mass. This study aimed to determine whether heart mass estimation can be improved when age, sex, and body dimensions are used as well as heart volume. Eighty-seven (24 female) adult post-mortem cases were investigated. Univariable predictors of heart mass were determined by Spearman correlation and simple linear regression. Stepwise linear regression was used to generate heart mass prediction equations. Heart mass estimate performance was tested using median mass comparison, linear regression, and Bland-Altman plots. Median heart mass (P = 0.0008) and heart volume (P = 0.008) were significantly greater in male relative to female cases. Alongside female sex and body surface area (BSA), heart mass was univariably associated with heart volume in all cases (R2 = 0.72) and in male (R2 = 0.70) and female cases (R2 = 0.64) when segregated. In multivariable regression, heart mass was independently associated with age and BSA (R2 adjusted = 0.46-0.54). Addition of heart volume improved multivariable heart mass prediction in the total cohort (R2 adjusted = 0.78), and in male (R2 adjusted = 0.74) and female (R2 adjusted = 0.74) cases. Heart mass estimated from multivariable models incorporating heart volume, age, sex, and BSA was more predictive of actual heart mass (R2 = 0.75-0.79) than models incorporating either age, sex, and BSA only (R2 = 0.48-0.57) or heart volume only (R2 = 0.64-0.73). Heart mass can be more accurately predicted from heart volume measured from PMCT when combined with the classical predictors, age, sex, and BSA.

Depth-Resolved Enhanced Spectral-Domain OCT Imaging of Live Mammalian Embryos Using Gold Nanoparticles as Contrast Agent.

High-resolution and real-time visualization of the morphological changes during embryonic development are critical for studying congenital anomalies. Optical coherence tomography (OCT) has been used to investigate the process of embryogenesis. However, the structural visibility of the embryo is decreased with the depth due to signal roll-off and high light scattering. To overcome these obstacles, in this study, combined is a spectral-domain OCT (SD-OCT) with gold nanorods (GNRs) for 2D/3D imaging of live mouse embryos. Inductively coupled plasma mass spectrometry is used to confirm that GNRs can be effectively delivered to the embryos during ex vivo culture. OCT signal, image contrast, and penetration depth are all enhanced on the embryos with GNRs. These results show that after GNR treatment, more accurate spatial localization and better contrasting of the borders among organs can be observed on E9.5 and E10.5 mouse embryos. Furthermore, the strong optical absorbance of GNRs results in much clearer 3D images of the embryos, which can be used for calculating the heart areas and volumes of E9.5 and E10.5 embryos. These findings provide a promising strategy for monitoring organ development and detecting congenital structural abnormalities in mice.

Low body mass index correlates with low left ventricular mass index in patients with severe anorexia nervosa.

The patients with anorexia nervosa (AN) are known to be associated with high mortality, but the actual causes of death are still undefined. We tested the hypothesis that AN patients had cardiac disorders, including left ventricular (LV) dysfunction and LV atrophy. This study is a cross-sectional study at St. Luke's International Hospital, Tokyo. We analyzed 13 female inpatients with AN. We assessed cardiac function and heart volume in AN by echocardiography, LV ejection fraction (LVEF), LV mass, and LV mass index (LVMI). We assessed the correlations between body mass index (BMI) and heart volume (LV mass and LVMI). The mean age and BMI were 34.8 ± 11.2 years and 15.5 ± 3.1 kg/m2, respectively. There was no patient with mitral valve prolapse, but 3 patients had trivial to small amount of pericardial effusion. The mean LVEF was 67.7 ± 6.5%, and 12 out of 13 patients had normal LVEF. Their LV mass (89.0 ± 27.3 g) and LVMI (66.3 ± 16.4 g/m2) were small. BMI positively correlated with LVMI (r = 0.58, p = 0.040), as well as LV mass (r = 0.74, p = 0.004). Lower BMI reflects lower LVMI, as well as smaller LV mass. These issues suggest that heart volume is initially decreased in severe AN conditions. Low LVMI could be a good marker of severity of AN.

Acute right heart failure caused by tacrolimus after renal transplantation: Serial observation by speckle tracking and Doppler echocardiography.

Tacrolimus is an immunosuppressive agent well known to be capable of producing renal impairment. Acute renal failure with right heart failure caused by tacrolimus is rarely described. We report the findings of one such case in which tacrolimus caused acute renal failure with severe tricuspid regurgitation and right ventricular failure documented by echocardiography.

Effects of Long-Term Endurance Exercise on Cardiac Morphology, Function, and Injury Indicators among Amateur Marathon Runners.

The purpose of this study was to investigate the effects of long-term endurance exercise on cardiac morphology and function, as well as injury indicators, among amateur marathon runners. We recruited 33 amateur runners who participated in a marathon. Participants were divided into experimental and control groups according to their National Athletic Grade. The experimental group included participants with a National Athletic Grade of 2 or better, and the control group included participants who did not have a National Athletic Grade. Cardiac morphology, function, and injury indicators were assessed before and after the participants' involvement in the Changsha International Marathon. All cardiac morphology and function indicators returned to pre-race levels at 24 h post-race, and left ventricular end-diastolic volume and left ventricular end-systolic volume indicators showed similar trends. Both stroke volume (SV) and percent fractional shortening (%FS) indicators showed similar trends in changes in the measurements before and after the race. SV showed no change between the pre-race and post-race periods. On the other hand, %FS showed a significant increase in the immediate post-race period, followed by restoration of its level at 24 h post-race. Among myocardial injury indicators, serum levels of cardiac troponin I, creatine kinase (CK), creatine kinase-MB (CK-MB), lactate dehydrogenase (LDH), aspartate aminotransferase (AST), and N-terminal pro-b-type natriuretic peptide (NT-proBNP) measured before the race, immediately after the race, and 24 h after the race displayed similar trends in changes among CK, CK-MB, LDH, and AST, while NT-proBNP levels did not change. We concluded that high-level amateur marathon runners had greater heart volumes, as well as wall and septal thicknesses, than low-level marathon runners, with differences in heart volume being the most pronounced. Long-term high-intensity endurance exercise caused some damage to the hearts of amateur runners. High-level runners showed better myocardial repair ability, and their levels of myocardial injury markers showed greater decreases at 24 h post-race, while low-level runners had poorer myocardial repair ability.

Effect of Exercise-Induced Reductions in Blood Volume on Cardiac Output and Oxygen Transport Capacity.

We wanted to demonstrate the relationship between blood volume, cardiac size, cardiac output and maximum oxygen uptake ( V . O2max) and to quantify blood volume shifts during exercise and their impact on oxygen transport. Twenty-four healthy, non-smoking, heterogeneously trained male participants (27 ± 4.6 years) performed incremental cycle ergometer tests to determine V . O2max and changes in blood volume and cardiac output. Cardiac output was determined by an inert gas rebreathing procedure. Heart dimensions were determined by 3D echocardiography. Blood volume and hemoglobin mass were determined by using the optimized CO-rebreathing method. The V . O2max ranged between 47.5 and 74.1 mL⋅kg-1⋅min-1. Heart volume ranged between 7.7 and 17.9 mL⋅kg-1 and maximum cardiac output ranged between 252 and 434 mL⋅kg-1⋅min-1. The mean blood volume decreased by 8% (567 ± 187 mL, p = 0.001) until maximum exercise, leading to an increase in [Hb] by 1.3 ± 0.4 g⋅dL-1 while peripheral oxygen saturation decreased by 6.1 ± 2.4%. There were close correlations between resting blood volume and heart volume (r = 0.73, p = 0.002), maximum blood volume and maximum cardiac output (r = 0.68, p = 0.001), and maximum cardiac output and V . O2max (r = 0.76, p < 0.001). An increase in maximum blood volume by 1,000 mL was associated with an increase in maximum stroke volume by 25 mL and in maximum cardiac output by 3.5 L⋅min-1. In conclusion, blood volume markedly decreased until maximal exhaustion, potentially affecting the stroke volume response during exercise. Simultaneously, hemoconcentrations maintained the arterial oxygen content and compensated for the potential loss in maximum cardiac output. Therefore, a large blood volume at rest is an important factor for achieving a high cardiac output during exercise and blood volume shifts compensate for the decrease in peripheral oxygen saturation, thereby maintaining a high arteriovenous oxygen difference.

Dosimetric analysis of Deep Inspiratory Breath-hold technique (DIBH) in left-sided breast cancer radiotherapy and evaluation of pre-treatment predictors of cardiac doses for guiding patient selection for DIBH.

INTRODUCTION: The risk of radiotherapy-associated cardiovascular disease has been a concern for decades in breast cancer survivors. The objective of our study is to evaluate the dosimetric benefit of Deep Inspiratory Breath-hold technique (DIBH) on organs-at-risk (OAR) sparing in left-sided breast cancer radiotherapy and to find out pre-treatment predictors of cardiac doses for guiding patient selection for DIBH. MATERIAL AND METHODS: Pre-radiotherapy planning CT scans were done in Free Breathing (FB) and in DIBH [using Active Breathing Coordinator system (ABC™)] in 31 left sided breast cancer patients. 3DCRT plans were generated for both scans. Comparison of anatomical and dosimetric variables were done using paired t test and correlation was evaluated using Pearson correlation. Linear regression was used to get independent predictors of cardiac sparing and Receiver Operating Characteristic (ROC) curve analysis was done to find out the specific threshold of the predictors. RESULTS: There was a 39.15% reduction in mean heart dose in DIBH compared to FB (2.4 Gy vs 4.01 Gy) (p < 0.001), 19% reduction in maximum Left Anterior Descending (LAD) dose and a 9.9% reduction in ipsilateral lung mean dose (p = 0.036) with DIBH. A significant correlation was observed between reduction in Heart Volume in Field (HVIF) and Maximum Heart Depth (MHD) with reduction in mean heart dose. Reduction in HVIF (ΔHVIF) independently predicted cardiac sparing. CONCLUSION: DIBH leads to significant reduction in OAR doses and is suggested for all patients of left-sided breast cancer undergoing radiotherapy. However, HVIF and MHD predicted for cardiac sparing and threshold criteria of ΔHVIF and ΔMHD may be used by centres with high workload to select patients for DIBH.

Isolated Partial Anomalous Pulmonary Venous Connection: Development of Volume Overload and Elevated Estimated Pulmonary Pressure in Adults.

OBJECTIVE: Partial anomalous pulmonary venous connection (PAPVC) is one of the rare congenital cardiac diseases with a prevalence of 0.4-0.7% of autopsies. The prevalence of a partial anomalous pulmonary venous connection is 0.2% in computed tomography (CT) among adults. We chose to study the association between isolated PAPVC and volume overload, estimated systolic pulmonary artery pressure in a tertiary care center for cardiovascular diseases. METHODS: CT report database was searched for keywords of partial anomalous pulmonary venous connection, pulmonary hypertension, dilated right atrium (RA), and right ventricle (RV). Both pediatric and adult population were considered. All the dedicated studies of non-coronary cardiac evaluation, pulmonary arteries, and thorax were included in the study. Echocardiography was performed in all the subjects. In adults, abnormalities searched were features of volume overload of RA and RV and estimated systolic pulmonary pressure of 45 mmHg. Biphasic studies were performed, and upper abdomen was included in the CT studies. RESULTS: Among the 110 subjects, 54 (49%) had isolated PAPVC. Of 54, 26 patients had volume overload of RA/RV or elevated estimated systolic pulmonary artery pressure. There is a significant association between drainage of anomalous veins to superior vena cava (SVC) and age >18 years (Chi-squared test P = 0.003). Among patients with isolated PAPVC, 18 had anomalous drainage to the SVC. Among isolated PAPVC cases, 38 were of the age >18 years. We found statistically significant association (P = 0.02) between isolated PAPVC in adults and pulmonary hypertension. CONCLUSION: Isolated PAPVC has association with the development of pulmonary hypertension in adults, approaching statistically significant p value. Because isolated PAPVC is a clinically significant independent risk factor, it should be actively treated to prevent the development of pulmonary hypertension later in life, which may result in severe clinical consequences.

CT-based anatomical features of large airway and heart volume in dogs of different body size.

Differences in the prevalence and clinical signs of cardiopulmonary diseases in dogs of different body sizes have been reported. It was hypothesized that the anatomical features of the heart and large airways varies by body size in dogs and might influence clinical manifestations of cardiopulmonary disease. The purpose of this study was to compare various anatomical features of the thoracic organs (heart, trachea, etc.) in dogs according to body size using computed tomography (CT) images. Dogs without clinically significant heart and lung disease (n=226) that underwent CT were divided into three groups on the basis of bodyweight: small (<7kg), medium (7-20kg), and large (>20kg). The following parameters were calculated from CT images using OsiriX and compared among groups: relative heart volume (heart volume/thoracic volume), relative distance from mainstem bronchi to vertebra (distance from mainstem bronchi to vertebra/heart length), longitudinal/transverse diameter ratio of trachea, and angle of bronchus. Small dogs had larger hearts relative to their thorax, a shorter distance from the heart to the vertebra, and laterally-elongated oval-shaped tracheas, compared to medium and/or large dogs. These differences in anatomical features according to body size may potentially contribute to different clinical manifestations when the heart is enlarged.

Changes in cardiac volume determined with repeated enhanced 4DCT during chemoradiotherapy for esophageal cancer.

BACKGROUND: Concurrent chemoradiotherapy is considered curative intent treatment for patients with non-operative esophageal cancer. Radiation-induced heart damage receives much attention. We performed repeated four-dimensional computed tomography (4DCT) to detect changes in cardiac volume during radiotherapy for esophageal cancer patients, and explored potential factors responsible for those changes. METHODS: Forty-six patients with esophageal cancer underwent enhanced 4DCT and three-dimensional (3D) CT scans before radiotherapy and every 10 fractions during treatment. The heart was contoured on 3DCT images, 4DCT end expiratory (EE) images and 4DCT maximum intensity projection (MIP) images by the same radiation oncologist. Heart volumes and other relative parameters were compared by the SPSS software package, version 19.0. RESULTS: Compared with its initial value, heart volume was smaller at the 10th fraction (reduction = 3.27%, 4.45% and 4.52% on 3DCT, EE and MIP images, respectively, p < 0.05) and the 20th fraction (reduction = 6.05%, 5.64% and 4.51% on 3DCT, EE and MIP images, respectively, p < 0.05), but not at the 30th fraction. Systolic and diastolic blood pressures were reduced (by 16.95 ± 16.69 mmHg and 7.14 ± 11.64 mmHg, respectively, both p < 0.05) and the heart rate was elevated by 5.27 ± 6.25 beats/min (p < 0.05) after radiotherapy. None of the potential explanatory variables correlated with heart volume changes. CONCLUSIONS: Cardiac volume reduced significantly from an early treatment stage and maintained the reduction until the middle stage. The heart volume changes observed on 3DCT and 4DCT were consistent during radiotherapy. The changes in heart volume, blood pressure and heart rate may be valuable indicators of cardiac impairment and target dose changes.

A longitudinal study on cardiac effects of deconditioning and physical reconditioning using the anterior cruciate ligament injury as a model.

BACKGROUND: Studies of cardiovascular deconditioning are primarily carried out after experimental bed rest. No previous study has followed the cardiovascular effects of decreased and resumed physical activity in athletes after acute physical injury and convalescence. Anterior cruciate ligament (ACL) injury causes a significantly decreased activity level over a long period, making it an ideal model for studying effects of deconditioning and reconditioning. Therefore, the aim of this study was to investigate how cardiac dimensions and maximal exercise capacity change after an ACL-injury. METHOD: Seventeen athletes (5 women) were included. Cardiac magnetic resonance (CMR) was performed within 5 days of the injury (CMR1), before endurance training was resumed (CMR2) and 6 months after the second scan (CMR3). Maximal exercise testing was performed on the same day as CMR2 and 3. RESULTS: The deconditioning phase between CMR1 and CMR2 was 59 ± 28 days. Total heart volume (THV) decreased with -3·1 ± 6·7%, P = 0·056. Between CMR2 and 3 (reconditioning), THV increased significantly (2·5 ± 4·6%, P<0·05). Left and right ventricular EDV decreased during deconditioning (-3·0 ± 5·6% and -4·7 ± 6·6%) and increased during reconditioning (1·7 ± 3·9% and 2·6 ± 6·2%) however not statistically significant. Left ventricular mass (LVM) remained unchanged. VO2 peak (mlmin(-1) kg(-1) ) increased significantly during the reconditioning phase (6·1 ± 5·3%, P<0·001). CONCLUSION: Physiological cardiac adaptation to deconditioning and reconditioning caused by severe knee injury with maintained normal daily living during convalescence was smaller than previously shown in bed rest studies. Total heart volume and VO2 peak were significantly affected by reconditioning whilst LVEDV, RVEDV and LVM remained unchanged over the study period.