Ventricular Diastole Research Articles

Echo-Doppler ultrasonographic assessment of resistance and velocity of blood flow in the ductus venosus throughout gestation in fetal lambs

It has been postulated that during fetal hypoxia, the blood flow shunted through the ductus venosus increases and may account for upto 70% of the total umbilical flow. The objectives of the present study were to use ultrasonography to determine the velocities and waveform indices of blood flow in the ductus venosus in the fetal lamb. The ductus venosus of 15 lamb fetuses was evaluated weekly from Days 45 to 143 of gestation (Day 0=day of AI). The Doppler indices measured were: S/D, the systole/diastole ratio; RI, the resistance index; and PI, the pulsatility index. The velocity waveforms studied were: SV, the peak velocity during ventricular systole; D, the peak velocity during ventricular diastole; aV, the lowest forward velocity during atrial contraction; and TAMV, the time-averaged maximum velocity. Doppler indices from Days 52 to 143 were highly correlated: S/D versus PI (r=0.96, P<0.0001), and versus RI (r=0.93, P<0.0001); and PI versus RI (r=0.97, P<0.0001). Velocity indices were also positively correlated: velocity SV versus D (r=0.87, P<0.0001), versus aV (r=0.79, P<0.05), and versus TAMV (r=0.98, P<0.0001); D versus aV (r=0.88, P<0.05), and versus TAMV (r=0.87, P<0.05); and aV versus TAMV (r=0.82, P<0.05). Doppler indices were negatively correlated with SV (r=-0.22, P<0.03); D (r=-0.37, P<0.0001); TAMV (r=-0.32, P<0.05) and with aV (r=-0.67, P<0.05). The mean value of each Doppler index decreased 40% from Days 52 to 73 (e.g., PI from 0.82+/-0.08 to 0.51+/-0.10; P<0.05), with no significant changes thereafter. Mean (+/-S.E.M.) values of velocity indices SV, D, aV, and TAMV rose twofold from Days 60 to 115 of gestation (e.g., SV from 54.4+/-8.8cm/s to 104.9+/-19.7 and aV from 24.8+/-6.9 to 54.9+/-5.9; P<0.05). In conclusion, Doppler ultrasonography facilitated assessment of the blood flow pattern in the ductus venosus in lamb fetuses between Days 52 and 143.

Non‐influence of fetal gender on ductus venosus Doppler flow in the first trimester

Recent findings have suggested that ductus venosus blood flow may be influenced by fetal gender. The aim of this study was to investigate further the influence of fetal gender on ductus venosus Doppler flow in the first trimester. This was a cross-sectional and retrospective study performed between January 1998 and January 2003. A total of 932 fetuses at between 10 and 14 weeks' gestation were included. The following inclusion criteria were used: singleton gestation; crown-rump length between 39 and 84 mm; and absence of fetal anomalies. The following variables of the ductus venosus were evaluated: peak velocity during ventricular systole (S-wave) and diastole (D-wave); nadir during atrial contraction in late diastole (A-wave); pulsatility index for veins (PIV); peak velocity index for veins (PVIV); and time-averaged maximum velocity (TAMXV). Four hundred and forty-eight (48.1%) female and 484 (51.9%) male fetuses were included in the study. Comparing males and females at between 10 and 14 weeks' gestation, there was no statistically significant difference in S-wave, D-wave, A-wave, PIV, PVIV or TAMXV. Our study suggests that fetal gender does not influence ductus venosus blood flow in the first trimester.

Relationships between velocities of pulmonary venous flow and plasma concentrations of atrial natriuretic peptide in healthy dogs

To investigate the relationship between velocities of pulmonary venous flow (PVF) and plasma concentrations of atrial natriuretic peptide (ANP) in healthy dogs. 7 healthy Beagles. Dogs were anesthetized, intubated, and positioned in left lateral recumbency. Lactated Ringer's solution was infused (200 mL/kg/h) for 60 minutes via a cephalic vein. Transmitral flow and PVF velocities were measured echocardiographically by use of the apical 4-chamber view. Pulmonary capillary wedge pressure (PCWP) and ANP concentrations were determined. IV infusion significantly increased heart rate and PCWP. Similarly, the ANP concentration significantly increased from baseline (before infusion of lactated Ringer's solution) values. Transmitral flow velocities were significantly increased, although the ratio of velocity of the flow during early ventricular diastole (E wave) to velocity of the atrial flow (A wave; E:A ratio) was unchanged. Regarding the PVF velocities, forward flow during ventricular systole (S wave) and retrograde flow during atrial contraction were significantly increased, whereas velocity of the forward flow during ventricular diastole (D wave) was unchanged. Ratio of the velocity of the S wave to velocity of the D wave was increased significantly, and this ratio was significantly correlated with PCWP or ANP concentration. However, the E:A ratio was not correlated with PCWP or ANP concentration. PVF velocities were strongly correlated with PCWP and plasma ANP concentration in clinically normal dogs. Therefore, PVF velocities may serve as a sensitive indicator and provide additional information for monitoring acute preloading conditions and estimating atrial filling abnormalities in dogs.

Flottierender rechtsatrialer Thrombus als Ursache rezidivierender Lungenembolien

After an attack of pleuropneumonia a 25-year-old woman developed persistent dyspnoea due to pulmonary emboli, as demonstrated by scintigraphy. There was no clinical or phlebographic evidence of the peripheral venous system as the source. Two-dimensional echocardiography demonstrated a floating spherical tumour in the right atrium, attached to the interatrial septum and prolapsing into the right ventricle during ventricular diastole. Because of the risk of further thromboembolic episodes the tumour was removed operatively without any complication. It proved to be myxoma-like, 3 x 3 cm in diameter. Histologically it was a thrombus without evidence of myxoma. No further thromboemboli occurred under phenprocoumon anticoagulation.

Loss of diastolic time as a mechanism of exercise-induced diastolic dysfunction in dilated cardiomyopathy

Cardiac performance can be characterized in terms of the relative duration of left ventricular systole and diastole. Little is known about exercise-induced abnormalities of the systolic-diastolic phase proportion and its impact on hemodynamic variables in patients with idiopathic dilated cardiomyopathy (IDCM). The phases of the cardiac cycle were derived with high temporal resolution from the left ventricular time-activity curve simultaneous with hemodynamic measurements. In patients with IDCM, the loss of diastolic time (LDT) per beat was quantified using a regression equation obtained from a healthy control group (n = 26). According to the median LDT at peak exercise, patients were divided into 2 subgroups: subgroup A with an LDT <or=22 milliseconds (n = 28) and subgroup B with an LDT >22 milliseconds (n = 27). The relative duration of left ventricular systole was increased in patients with IDCM during peak exercise compared to healthy subjects (29.3 vs 26.7 s/min, P < .02). This abnormality translated into a significant LDT when observed, and predicted values of diastolic time were compared. Subgroup B patients had a higher increment in mean pulmonary capillary wedge pressure but a smaller increase in stroke volume index from rest to peak exercise (14.3 vs 8.6 mm Hg [P = .007] and 12.5 vs 7.2 mL/m(2) [P = .04]) compared to subgroup A patients. An abnormal shortening of diastolic time during exercise can restrict left ventricular filling to an extent that is sufficient to limit left ventricular stroke volume reserve and to cause pulmonary congestion.

Ductus venosus Doppler velocimetry in the first trimester: a new finding

To establish reference curves for ductus venosus blood flow velocities during the first trimester and compare them with previously published curves. This was a cross-sectional and retrospective study performed between January 1998 and January 2003. The following inclusion criteria were used: singleton pregnancy, velocity measurements taken when the crown-rump length (CRL) was between 34 and 84 mm, absence of fetal anomalies, full-term pregnancy and newborn birth weight appropriate for gestational age. The following variables of the ductus venosus were measured: peak velocity during ventricular systole (S-wave) and diastole (D-wave), nadir during atrial contraction in late diastole (A-wave), time-averaged maximum velocity (TAMXV) and pulsatility index for veins (PIV). A total of 843 fetuses were included. The mean CRL was 62 (range, 34-84) mm. The S-wave, D-wave, TAMXV and PIV were normally distributed, and logarithmic transformation was performed to achieve a normal distribution for the A-wave. S-wave, D-wave and A-wave and TAMXV increased with CRL. PIV increased up to a CRL of 63 mm and decreased thereafter. Regression analysis revealed a significant quadratic relationship between PIV and CRL. S-wave, D-wave, A-wave velocities and TAMXV in the ductus venosus increase with CRL between 34 and 84 mm. The reference range for PIV has a biphasic pattern, with an initial non-significant increase up to a CRL of 63 mm and a fall thereafter.

Left Atrial Stiffness and its Implications for Cardiac Function

Proper atrial function is essential for overall cardiovascular performance, mainly by its four major functions, namely, bioelectrical, hormonal, metabolic and hemodynamic. With regard to the latter, atria modulate ventricular filling by smoothing the transformation of the continuous venous return to the intermittent filling pattern of the ventricles during diastole through three main components: a phase of reservoir mainly during ventricular systole, a conduit phase during ventricular diastole and an active phase in late ventricular diastole. Although the atria assume a dynamic role in ventricular filling progression, atrial function and emptying pattern is, conversely, highly influenced by the ventricular diastolic wall stress, underlying the close connection observed between these chambers. This review focuses essentially on left atrial mechanical role, particularly on the physiological and clinical consequences of disturbed atrial compliance.

Effects of Tribuli Saponins on Ventricular Remodeling after Myocardial Infarction in Hyperlipidemic Rats

This experiment was designed to determine whether Tribuli saponins (TS) relieve left ventricular remodeling (VR) after myocardial infarction (MI) in a murine hyperlipemia (HL) model. MI and HL models were induced and high and low doses of TS and simvastatin were administrated to the rats. Four weeks later, echocardiographic observation was performed and the left and right ventricular weight index (LVWI, RVWI) was calculated. Echocardiographic results showed that both high dose of TS and simvastatin had a beneficial effect on increasing fractional shortening (FS) and ejection fraction (EF), reducing left ventricular end diastolic volume (LVEDV), systolic volume (LVESV), left ventricular dimension end diastole (LVDd) and systole (LVDs), and decreasing LVWI, as compared to those in the HL-MI model group (p < 0.05, 0.01). Both medicines had little impact on thickness of the anterior and posterior wall. No significant difference was observed between each treatment group (p > 0.05). In conclusion, TS not only lowered serum lipidemia, but also relieved left ventricular remodeling, and improved cardiac function in the early stage after MI.

Variation in pulmonary vein size during the cardiac cycle: Implications for non–electrocardiogram-gated imaging

Understanding pulmonary vein (PV) anatomy is important for the planning and execution of PV isolation for the treatment of atrial fibrillation, screening for PV stenosis after the procedure, and investigating the pathophysiology of atrial fibrillation. We hypothesized that significant changes in PV size occur during the cardiac cycle and sought to identify the relationship of data obtained with conventional non-electrocardiogram (ECG)-gated methods compared with ECG-gated measures of PV size using cardiovascular magnetic resonance. A consecutive series of 14 patients in sinus rhythm were evaluated with non-ECG-gated contrast-enhanced magnetic resonance angiography and ECG-gated cine cardiovascular magnetic resonance of the PV. Pulmonary vein diameter, perimeter, and cross-sectional area (CSA) were measured using both methods. Maximum diameter, perimeter, and CSA occurred simultaneously in all PV. The timing of the maximum size varied but generally occurred in ventricular diastole (101 +/- 112 milliseconds after mitral valve opening). The timing of minimum PV size also varied but generally occurred in ventricular systole (212 +/- 90 milliseconds before mitral valve opening). The difference between the maximum and minimum PV size was 15% +/- 8% for diameter, 15% +/- 7% for perimeter, and 27% +/- 12% for CSA (P < .001 for all). Contrast-enhanced magnetic resonance angiography correlated best with the ECG-gated maximum PV size (R2 > 0.48, P < .001 for all) and was greater than the minimum and average PV sizes (P < .05 for all). All measures of PV size vary significantly during the cardiac cycle. Contrast-enhanced magnetic resonance angiography PV measurements correlate best with maximum PV size.

Left atrial emptying fraction correlation with vascular pedicle width in patients with normal systolic function.

To determine the correlation and diagnostic utility of impaired left atrial emptying fraction, an indicator of diastolic dysfunction, with raised intravascular volume determined by vascular pedicle width on upright postero-anterior chest roentgenogram. Cohort study. Department of Medicine, King Abdulaziz National Guard Hospital, Alhasa, Saudi Arabia from October till December 2002. Thirty-two out of 56 patients with normal systolic function (ejection fraction >50%) on echocardiogram were included in the study. Left atrial dimensions were measured at the end of left ventricular diastole (LADed) and systole (LADes) on M-mode tracing. Left atrial emptying fraction (LAEF) was calculated by dividing LADed by LADes. Ratio of peak early diastolic velocity (E/A) to peak late diastolic velocity, isovolemic relaxation time (IVRT) and deceleration time of E-wave (DT) were also recorded on transmitral Doppler signal. Postero-anterior views of chest X-rays done within 48 hours of echocardiogram were studied for the measurement of vascular pedicle width (VPW) and cardiothoracic ratio (CTR). Univariate and multiple regression analysis were performed to identify possible predictors of VPW. Receiver operator curves were constructed to see diagnostic utility of impaired LAEF for raised intravascular volume measured by VPW. Mean age for the patients was 58.56 +/- 17 years. There were 15 females (46.9%) and 17 males (54.1%). LADes, LADed, LAEF and DT were 2.89 +/- 0.63 cm, 3.81 +/- 0.53 cm, 0.75 +/- 0.10 and 202 +/- 49.9 msec respectively. VPW and CTR were 55.81 +/- 10.2 mm and 0.54 +/- 0.08. Significant independent predictors of VPW on univariate regression analysis were entered into multiple regression models, which revealed LAEF and DT as the only predictors of VPW. The final regression equation was VPW = 15.43 + 35.7 (LAEF) + 0.06 (DT), R2 = 0.35, p = 0.0008. LAEF > 0.75 had a sensitivity of 74% and specificity of 94% for diagnosing raised intravascular volume defined as VPW > 53 mm. LAEF > 0.75 is a reliable indicator of intravascular volume expansion in patients with normal systolic function signifying diastolic dysfunction and activation of salt and water retaining mechanisms.

Direct Effects of TNF‐α on Fibronectin Generation in Rats with Heart Failure

Elevated left artrial pressures (LAPs) are common in patients with heart failure. We have demonstrated TNF-α is the primary proinflammatory cytokine in fibrogenesis in our elevated LAP model. We investigated the direct effects of TNF-α production in our rat model of elevated LAP-induced pulmonary fibrosis. The modulatory influences of TNF-α on fibronectin generation in 1) sham-control, 2) rats subjected to elevated LAP, and 3) rats subjected to LAP in the presence of pentoxyfilline (PTX), a methylxanthine derivative of a phosphodiesterase inhibitor were assessed. A catheter was introduced into the left ventricle to record left ventricular end diastole pressure. A wire was introduced through the left ventricle to restrict left ventricular filling during cardiac diastole, causing an increase in LAP about 15–20 mm Hg above baseline. 18 rats were divided into 3 groups (n=6). Group 1 was sham-control, Group 2 was subjected to elevated LAP, whereas Group 3 was subjected to elevated LAP in the presence of PTX (1mg/kg/hr for 4 days), infused through an osmotic minipump to down-regulate proinflammatory TNF-α production by alveolar macrophages. Amounts of TNF-α and fibronectin in the presence and absence of PTX were measured in alveolar macrophages using an ELISA assay. Our data show in rats treated with PTX, lung fluid decreased significantly by 35% compared to non-treated rats with elevated LAP (2.74 ± 0.32 vs 4. 21 ± 0.57 ml/kg respectively). PTX inhibits TNF-α production by 90% and fibronectin by 50%. Our data suggest fibronectin generation leading to fibroblast expansion is directly correlated to elevated TNF-α production in rats with elevated LAP. Research funded by NIH.

Evaluation of normal fetal left cardiac function by tissue doppler imaging

To explore the feasibility of using tissue Doppler imaging technique for the evaluation of fetus's left ventricular diastolic function, and to confirm its reliability by comparing it with traditional methods, this study examined 61 pregnant women in whom satisfactory images were obtained of fetal echocardiography. The peak velocity of blood stream were measured, including E, A and E/A at mitral valve orifice on the four chamber view with pulse wave. And then tissue Doppler imaging mode was employed to measure the velocity of mitral valve annulus including Ea, Aa, Sa and Ea / Aa. Correlation analysis was conducted between the velocity of orifice and that of annulus in terms of gestation age. And then correlation analysis was performed between above data and gestation ages. A positive correlation was found between the velocity of orifice and that of annulus, and the velocity increased with the gestation age. The change was the most significant between the 28th and the 34th week of gestation age. Our study showed that it is feasible to evaluate the fetus's left ventricular diastole function by tissue Doppler imaging. Its stability can avoid the influence of fetal heart rates and preload.

Cardiac Ventricular Diastolic and Systolic Duration in Children With Heart Failure Secondary to Idiopathic Dilated Cardiomyopathy

Systole and diastole are the fundamental periods of the cardiac cycle, yet little emphasis has been placed on their relative duration when evaluating heart failure. Cardiac intervals are used to assess ventricular function, but the relative duration of systole and diastole for defining function have not been evaluated. We hypothesized that in heart failure, systole is prolonged and diastole shortened. We defined systole and diastole in 16 children with idiopathic dilated cardiomyopathy and in 16 normal controls, matched for age and gender, using the mitral regurgitant (MR) and tricuspid regurgitant (TR) flow duration. The systole and diastole durations (expressed as a fraction of the cardiac cycle) were correlated with heart rate and age and compared between groups. The subjects were compared with gender- and age-matched controls (9.98 +/- 6.1 vs 9.88 +/- 6.08 years, p = NS). The 2 groups had similar heart rates (104 +/- 31 vs 92 +/- 34 beats/min, p = NS). The systole duration was not significantly different when measured by MR versus TR duration (0.60 +/- 0.10 vs 0.57 +/- 0.11 of the cardiac cycle, respectively, p = NS). Systole was prolonged in subjects compared with controls (0.60 +/- 0.1 vs 0.42 +/- 0.08, respectively, using MR duration, p < 0.0001 and 0.57 +/- 0.11 vs 0.41 +/- 0.07, respectively, using TR duration, p = 0.0008). The systolic/diastolic ratio was 0.77 +/- 0.24 in the controls versus 1.57 +/- 0.98 in the patients with idiopathic dilated cardiomyopathy using the TR duration (p < 0.005) and 1.67 +/- 0.68 using the MR duration (p < 0.0001). The systole duration correlated with heart rate in subjects (r = 0.79, p = 0.0003) and controls (r = 0.69, p = 0.003). In conclusion, systole is significantly prolonged and diastole correspondingly shortened in heart failure. Reversal of the normal systolic/diastolic ratio may compromise cardiac filling and function. The systole and diastole duration are easily measured using routine Doppler flow, enhancing assessment of cardiac function in children.

Issue Highlights

HomeCirculationVol. 112, No. 19Issue Highlights Free AccessIn BriefPDF/EPUBAboutView PDFView EPUBSections ToolsAdd to favoritesDownload citationsTrack citationsPermissions ShareShare onFacebookTwitterLinked InMendeleyReddit Jump toFree AccessIn BriefPDF/EPUBIssue Highlights Originally published8 Nov 2005https://doi.org/10.1161/circ.112.19.2887Circulation. 2005;112:2887REVERSE REMODELING OF THE LEFT CARDIAC CHAMBERS AFTER CATHETER ABLATION AFTER 1 YEAR IN A SERIES OF PATIENTS WITH ISOLATED ATRIAL FIBRILLATION, by Reant et al.In patients with atrial fibrillation and no specific associated heart disease, there are identifiable abnormalities in structure and function, including left atrial dilation and abnormalities in diastolic ventricular function. An intriguing issue has been whether diastolic abnormalities are cause or consequence; are filling abnormalities related to the abnormal atrial dynamics, or might diastolic dysfunction (and consequent left atrial dilation) represent a driver of atrial fibrillation onset and maintenance? In this issue of Circulation, Reant and colleagues begin to dissect this issue by studying patients with isolated atrial fibrillation with echocardiography before and then 5 times during the year after radiofrequency ablation back to sinus rhythm. Left atrial size decreased, ventricular diastolic parameters improved, and ejection fraction increased. These data suggest that atrial fibrillation results in reversible structural and functional atrial and ventricular abnormalities in the absence of other specific pathologies. Diastolic abnormalities appear in large part a consequence rather than a cause of atrial fibrillation. See p 2896.MINERALOCORTICOID RECEPTOR ANTAGONISM AMELIORATES LEFT VENTRICULAR DIASTOLIC DYSFUNCTION AND MYOCARDIAL FIBROSIS IN MILDLY SYMPTOMATIC PATIENTS WITH IDIOPATHIC DILATED CARDIOMYOPATHY: A PILOT STUDY, by Izawa et al.Landmark clinical trials have previously demonstrated the benefits of mineralocorticoid receptor antagonism in patients with symptomatic congestive heart failure. In fact, the Randomized Aldactone Evaluation Study (RALES) found that the addition of spironolactone to standard therapy reduced mortality by 30% in patients with NYHA class III or IV congestive heart failure. On the basis of these results, mineralocorticoid receptor antagonists have become widely accepted as part of the standard therapeutic regimen for patients with advanced symptoms due to congestive heart failure. It has been suggested that one mechanism by which mineralocorticoid receptor antagonists exert their beneficial effects is by decreasing myocardial fibrosis and, thereby, adverse ventricular remodeling; however, this effect has not been demonstrated directly. In this issue of Circulation, Izawa et al evaluate the effects of spironolactone on myocardial fibrosis regression in mildly symptomatic patients (NYHA class I or II) with dilated cardiomyopathy and correlate these findings with left ventricular diastolic function. See p 2940.ABSORPTION, METABOLIZATION, AND ANTIPLATELET EFFECTS OF 300-, 600-, AND 900-MG LOADING DOSES OF CLOPIDOGREL: RESULTS OF THE ISAR-CHOICE (INTRACORONARY STENTING AND ANTITHROMBOTIC REGIMEN: CHOOSE BETWEEN 3 HIGH ORAL DOSES FOR IMMEDIATE CLOPIDOGREL EFFECT) TRIAL, by von Beckerath et al.In patients undergoing percutaneous coronary intervention, the benefits of dual antiplatelet therapy with aspirin and clopidogrel after stent placement are well recognized; however, because of the variability in platelet inhibition observed among patients, investigators have questioned the optimal loading dose of this agent. Although the 300-mg loading dose of clopidogrel has been considered the standard regimen, recent studies have shown that a 600-mg loading dose provided additional, and more rapid, inhibition of platelet aggregation. Because of the observed benefit with an increased loading dose, investigators have now begun to study whether platelet inhibition may be augmented further by raising the loading dose to 900 mg. In this issue of Circulation, von Beckerath et al detail the results of a randomized trial of the antiplatelet effects and pharmacokinetics of 300-, 600-, and 900-mg loading doses of clopidogrel. See p 2946.Visit http://www.circ.ahajournals.org:Clinician UpdateHomocysteine and Its Effects on In-Stent Restenosis. See p e307.Images in Cardiovascular MedicineMedical Treatment of Varicose Veins. See p e312.Acute Type I Aortic Dissection With Concomitant Pulmonary Artery Dissection. See p e313.Detection of Active Coronary Arterial Vasculitis Using Magnetic Resonance Imaging in Kawasaki Disease. See p e315. Download figureDownload PowerPointCorrespondenceSee p e317. Previous Back to top Next FiguresReferencesRelatedDetails November 8, 2005Vol 112, Issue 19 Advertisement Article InformationMetrics https://doi.org/10.1161/circ.112.19.2887 Originally publishedNovember 8, 2005 PDF download Advertisement

Simultaneous measurement of blood and myocardial velocity in the rat heart by phase contrast MRI using sparse q‐space sampling

To measure cardiac blood flow patterns and ventricular wall velocities through the cardiac cycle in anesthetized Wistar Kyoto (WKY) rats. A gradient-echo cine pulse sequence incorporating pulsed field gradients (PFGs) provided phase contrast (PC) motion encoding. We achieved a range of velocity sensitivity that was sufficient to measure simultaneously the large flow velocities within the cardiac chambers and aortic outflow tract (up to 70 cm s(-1) during systole), and the comparatively small velocities of the cardiac wall (0-3 cm s(-1)). A scheme of sparsely sampling q-space combined with a probability-based method of velocity calculation permitted such measurements along three orthogonal axes, and yielded velocity vector maps in all four chambers of the heart and the aorta, in both longitudinal and transverse sections, for up to 12 time-points in the cardiac cycle. Left ventricular systole was associated with a symmetrical laminar flow pattern along the cardiac axis, with no appearance of turbulence. In contrast, blood showed a swirling motion within the right ventricle (RV) in the region of the pulmonary outflow tract. During left ventricular diastole a plume of blood entered the left ventricle (LV) from the left atrium. The ventricular flow patterns could also be correlated with measurements of left ventricular wall motion. The greatest velocities of the ventricular walls occurred in the transverse cardiac plane and were maximal during diastolic refilling. The cardiac wall motion in the longitudinal axis demonstrated a caudal-apical movement that may also contribute to diastolic refilling. The successful measurements of blood and myocardial velocity during normal myocardial function may be extended to quantify pathological cardiac changes in animal models of human cardiac disease.

Effects of animal position and number of repeated measurements on selected two-dimensional and M-mode echocardiographic variables in healthy dogs

To evaluate the effects of positioning and number of repeated measurements on intra- and interobserver variability of echocardiographic measurements in dogs. Prospective study. 4 healthy dogs. Each observer performed 24 examinations, separately assessing each dog 6 nonconsecutive times (3 times with the dog in lateral recumbency and 3 with the dog in a standing position). Variables evaluated included M-mode measurements of left ventricular end-diastolic and left ventricular end-systolic diameters, left ventricular free-wall thickness in diastole and systole, interventricular septal thickness in diastole and systole, left ventricular shortening fraction, and 2-dimensional measurements of the left atrial diameter-to-aortic diameter ratio. All coefficients of variation (range, 3.4% to 26.6%) were similar between operators and positions and were < 15% for 27 of 32 values. For both operators, repeatability of the measurements was better for left ventricular end-systolic diameter, left ventricular free-wall thickness in diastole, left ventricular free-wall thickness in systole, and the left atrial diameter-to-aortic diameter in the standing position, and similar for both positions for shortening fraction and left ventricular end-diastolic diameter. No effect of cardiac cycle was observed. Within-day variability of conventional echocardiography performed with the dog in the standing position was at least as good as that obtained with the dog in lateral recumbency for most measured variables. Single measurements of each variable may be sufficient for trained observers examining dogs that do not have an arrhythmia. The standing position should be used, particularly for stressed or dyspneic dogs.

Assessing Atrial Mechanical Remodeling and Its Consequences

The principal function of the left atrium is to modulate left ventricular (LV) filling and cardiovascular performance through reservoir, conduit, and booster pump functions; the latter is often (mistakenly) regarded synonymously with atrial function, and in contrast to the reservoir and conduit phases, has been studied extensively. Typically, the importance of atrial contraction has been estimated by measurements of cardiac output and end-diastolic volumes both with and without effective atrial systole, by relative LV filling using Doppler transmitral velocimetry (E/A ratios) or radionuclide angiography, or by atrial shortening using 2D echocardiography, angiography, and sonomicrometry. Despite considerable investigation, the magnitude and relative importance of the atrial contribution to LV filling and cardiac output remain controversial and provide motivation for a more complete evaluation of the atrial cycle. In this regard, nearly half of the LV stroke volume and its associated energy is stored in the left atrium during ventricular systole, which acts as a ventricular restoring force during the ensuing ventricular diastole.1 This reservoir function of the left atrium is governed by atrial compliance, which is most rigorously measured by mathematically fitting atrial pressure and volume data during ventricular systole. A number of studies have shown, however, that the proportion of left atrial inflow during ventricular systole with Doppler pulmonary venous flow (ie, S/D ratios) can estimate relative reservoir function. Thus, we showed that an isolated change in left atrial compliance alters predictably reservoir function and the pattern of pulmonary venous flow.2 Decreased atrial compliance is associated with greater phasic atrial pressures but a lower mean level of atrial pressure during ventricular filling, and as a result, a smaller end-diastolic volume and decreased venous return.3 In contrast, increased atrial compliance increases early LV filling and atrial systolic shortening.4 See p 387 Pressure-strain analysis in the intact dog …

Early prenatal diagnosis of endocardial fibroelastosis

Endocardial fibroelastosis is characterized by a diffuse thickening of the ventricular endocardium1, and usually leads to death from congestive heart failure in early infancy. It can be secondary to congenital heart malformations such as aortic stenosis or atresia, aortic coarctation, anomalous coronary arteries and ventricular septal defect2. Several factors may explain primary fibroelastosis2-4, including intrauterine viral myocarditis (mumps, coxsackie virus B)3, autoimmune processes (antibody deposition throughout the myocardium after passive transplacental passage of maternal anti-Ro/anti-La antibodies4, which induces inflammation and fibrosis in the developing myocardium), subendocardial ischemia, impaired lymphatic drainage of the heart, systemic carnitine deficiency, and mucopolysaccharidosis. In the 1960s, the incidence of endocardial fibroelastosis was 1 in 5000 live births2, 5 but it has dramatically decreased in occurrence since the use of the measles-mumps-rubella vaccination. Recurrence in subsequent pregnancies is estimated at 3–5%2. Although the disease is sporadic, 10% of cases are familial with various genetic mutations. A 32-year-old woman (gravida 2, para 1) underwent routine ultrasound examination at 12.5 weeks' gestation, which revealed a hypokinetic cardiac left ventricle with wall thickening (Figure 1). Two weeks later, hypokinesis was confirmed and was found to be associated with a hyperechogenic septum, aortic atresia and mitral stenosis. The pulmonary artery was the only visible vessel. Endocardial fibroelastosis was suspected and, following counseling, termination was performed at 15 weeks' gestation with intravaginal prostaglandin. Four-chamber view showing the left ventricle (LV) with a thickened wall at 12.5 weeks. (a) Ventricular diastole. (b) Ventricular systole. (c) Color Doppler imaging during ventricular diastole showing filling of the right ventricle (RV), but no flow in the left ventricle. On pathological examination, the fetus weighed 68 g and was 14 cm in length. Conclusive dissection of the four valves of the heart, which was 12 × 8 mm and weighed less than 1 g, was not possible. Macroscopically, the left ventricle presented with concentric hypertrophy with a thickened wall (2–3 mm) (Figure 2). The left atrium was hypoplastic. Histological examination showed a fibrous thickening of the endocardium with collagenous bands admixed between myocytes, which confirmed the diagnosis. The interventricular wall was thickened with microcalcifications. Macroscopic sections of the heart. Concentric hypertrophy of the left ventricle with a thickened wall (2–3 mm) and interventricular septum. Hypoplastic left atrium (original measurement 3 × 4 mm) compared to the right atrium (original measurement 7 × 9 mm). Primary and secondary endocardial fibroelastosis seem to follow the same pathophysiology2. The endocardial thickening results from ventricular hypokinesis secondary to a damaged myocardium. This chronic myocardial stress results in the production of collagen and elastin with fibroelastic thickening of the endocardium, which leads to myocardial dysfunction. In the literature, endocardial fibroelastosis has generally been reported in young children or in second- and third-trimester fetuses. However, the condition is likely to develop earlier in pregnancy, as we have shown, and as was also demonstrated by Rustico et al.5 who reported a case of endocardial fibroelastosis with aortic stenosis at 14.5 weeks' gestation. Our observation stresses the importance of first-trimester ultrasound examination, which can allow early termination for lethal diseases. Nevertheless, the benefits of such early systematic screening for heart diseases have to be weighed against the negative aspects6. When severe abnormalities are noticed so early it is likely that spontaneous miscarriage will ensue and parents should have the choice of continuing the pregnancy until it reaches its natural end. C. Trastour*, A. Bafghi*, J. Delotte*, C. Mainguene , B. Benoit*, A. Bongain*, * Department of Gynecology-Obstetrics-Infertility Fetal Medicine, Prenatal Diagnosis Unit, Archet II Hospital, 151 route St-Antoine de Ginestière BP 3079, 06202 cedex 3 Nice, France, Department of Pathology, Princess Grace Hospital, Monaco

Effects of Tribuli saponins on left ventricular remodeling after acute myocardial infarction in rats with hyperlipidemia

To observe the effect of Tribuli saponins (TS) on left ventricular remodeling after acute myocardial infarction (AMI) in rats with hyperlipemia. A composite model of myocardial infarction and hyperlipemia was established and treated with TS to observe its effect on cardiac structure and function by echocardiography. (1) Cardiac function: As compared with the model group, the fractional shortening (FS) and ejection fraction (EF) got increased, and the left ventricular end diastolic volume (LVEDV) and systolic volume (LVESV) got lower in the groups treated with high dose TS and simvastatin (P < 0.05 or P < 0.01), but difference between the two treated groups was insignificant. (2) Cardiac structure: As compared with the model group, the left ventricular dimension end diastole (LVDd) and systole (LVDs) in the groups treated with high dose TS and simvastatin got lower (P < 0.05 or P < 0.01). No treatment showed any effect on the thickness of ventricular wall. (3)Ventricular weight index: Both high dose TS and simvastatin could decrease the left ventricular weight index (LVWI) (P < 0.05). TS could attenuate the left ventricular remodeling after acute myocardial infarction to certain extent, and improve cardiac function in the early phase after AMI, thus playing an important role in controlling morbidity and mortality of cardiac events and long-term prognosis.

What’s the best assessment of preload after cardiac surgery?

The assessment of the role of transesophageal echocardiography and invasive tests with pulmonary modified catheter to monitor the preload indexes in patients in intensive-care-unit after cardiac coronary surgery. Between January and December 2004 24 patients (14 male, 10 female) with coronary artery disease were prospectively enrolled for preload assessment during off-pump myocardial revascularization. Pulmonary Capillary Wedge Pressure (PCWP), Left Ventricular End Diastolic Indexed Area (LVEDAI), delta Aortic Velocity (deltaVAo), Right Ventricular End Diastolic Volume (RVEDVI) as preload indexes were evaluated. Transesophageal echocardiography and pulmonary modified catheter monitoring were performed during the preoperative period at T1 and after fluid infusion (T2). Patients were considered Responders (R) or No Responders (NR) if the Stroke Volume Index increase at T2 was >20% with respect to T1. Mean T1 PCWP was similar in both groups (12.8+/-2.2 in R vs. 11.4+/-3 mmHg in NR; p=NS) and mean increase of PCWP at T2 was similar in both groups (1.5+/-0.3% in R vs. 1.2+/-3% in NR; p=NS). Mean T1 RVEDVI was similar in both groups (97.33+/-34 in R vs. 101+/-21 ml/m2 in NR; p=NS); T2 RVEDVI was similar in R and NR Groups (122.11+/-49 vs. 138.54+/-30 ml/m2; p=NS); mean T1 and T2 LVEDAI was similar in R and NR (11.2+/-3.5 vs. 10.2+/-2.3 at T1 and 14.04+/-3.35 vs. 14.67+/-2.1 cm2/m2 at T2 respectively; p=NS). Higher mean value of T1 deltaVAo (20+/-7% in R vs. 10+/-2% in NR; p=0.006) were recorded while similar mean value of T2 deltaVAo were observed (11+/-3% in R vs. 5+/-2% in NR; p=0.743). Correlation index between T1 and T2 deltaVAo (R=0.82) in R was significant (p=0.0002), while correlation index between T1 and T2 deltaVAo (R=0.11) in NR was not significant. Our study showed in patients soon after coronary cardiac surgery deltaVAo is the only predictor of "fluid responsiveness" and of ventricular compliance.