Pulsed-wave Doppler Echocardiography Research Articles

The effect of maternal weight on neonatal cardiac functions following diabetic and non-diabetic pregnancies.

We aimed to study myocardial functions of infants appropriate and large for gestational age (IDM-AGA, IDM-LGA) of diabetic mothers (IDM) and AGA and LGA infants of non-diabetic mothers comparatively. Newborns were assessed between 24 and 72 h. M-Mode, pulsed wave, and tissue Doppler echocardiography were performed. A negative correlation was found between shortening fraction and maternal weight at delivery in the LGA group (p=0.009, r=-0.58). E/Early diastolic (E') ratio and deceleration time were increased in IDM-AGA than AGA group (p=0.02, p=0.02). There was a negative correlation between maternal blood glucose and E/A ratio (p=0.015 r=-0.63), a positive correlation between maternal blood glucose and mitral A, late diastolic (A') wave in IDM-AGA (p=0.014 r=0.63, p=0.016 r=0.62). Maternal weight gain during pregnancy was in correlation with measured and tei index in IDM-AGA group (p=0.008 r=0.72). Maternal age, pre-pregnancy weight, and weight at delivery and mitral E were higher in IDM-LGA group than IDM-AGA (p=0.03, p=0.01, p=0.003, p=0.012). We found that maternal weight has a negative effect on myocardial function in LGA newborns. Diastolic functions were found impaired in IDM-AGA infants and in infants of mothers with high blood glucose. Maternal weight gain during pregnancy has a negative effect on myocardial functions.

Interventricular inflow time difference assessed by dual pulsed-wave Doppler echocardiography in dogs with myxomatous mitral valve disease

IntroductionInterventricular inflow time difference (IVID), which is defined as the time interval between the opening of the mitral valve and the opening of the tricuspid valve, hold prognostic value in human patients with heart failure. Few reports regarding IVID are available in dogs. AnimalsNinety dogs with myxomatous mitral valve disease (MMVD) and 47 dogs without heart disease. Dogs with MMVD received unstandardized therapy based on the stage of disease. Materials and methodsThis was a prospective cohort study. Dogs were classified into two groups based on IVID: tricuspid opening preceding mitral opening (TOP) and mitral opening preceding tricuspid opening (MOP). The potential influence of the MOP group at enrollment on the primary outcome (cardiac-related death) was determined by Kaplan–Meier analysis. ResultsAlmost all dogs without heart disease (97.9%) were classified in the TOP group. Twenty-nine dogs (32.2%) were classified in the MOP group. Left heart size, transmitral early diastolic inflow velocity, and right ventricular Tei index were significantly greater in the MOP group compared to those in the TOP group. Cardiac-related death were observed in 34 dogs (40.5%). The dogs in the MOP group at initial examination had shorter survival times than those in the TOP group (586 days vs. >1,831 days; 95% confidence interval, 237–714 days vs. 1,037 days to >1,831 days; P<0.001). ConclusionsInterventricular inflow time difference is potentially useful for prognostic assessments in dogs with MMVD. Further prospective studies that quantify the repeatability and influence of therapy on IVID are needed.

Abstract 13419: Transient Coronary Artery to Left Ventricular Fistula With Diastolic Mitral Regurgitation

Introduction: A fistula from a coronary artery to the cardiac chamber is incidentally found in 0.08% to 0.3% of patients undergoing coronary angiography. Case Presentation: A 73-year-old woman with hypertension, diabetes mellitus, chronic renal failure, and nephrosis visited our department due to dyspnea. The patient’s physical examination revealed a blood pressure of 191/109 mmHg and a pulse rate of 77 beats per min. The blood sampling results revealed a plasma brain natriuretic peptide level of 2,001 pg/mL. A 12-lead electrocardiogram showed poor R wave progression in leads V1 to V4. Chest radiography revealed left pleural effusion. Parasternal transthoracic echocardiography showed left ventricular hypertrophy. Left ventricular (LV) ejection fraction was 41%. A pulsed-wave Doppler echocardiography at the mitral inflow showed diastolic mitral regurgitation and a fusion of E and A waves. An unusual myocardial flow was noted in the apical myocardium. It was directed toward the apical surface during systole (Fig. 1a), and directed toward the LV lumen during diastole (Fig. 1b), suggesting coronary artery to LV fistula through sinusoid. Global strain obtained from apical long axis imaging showed myocardial shortening continued to diastole, suggesting post-systolic shortening (PSS). After treatment for hypertension, both of myocardial flow and diastolic MR disappeared. A longitudinal global strain imaging revealed disappearance of PSS. Conclusion: This is a rare case of diastolic MR due to PSS at the fistula from the coronary artery to the left ventricle.

Mid-ventricular Obstructive Cardiomyopathy after Takotsubo Cardiomyopathy: A Case Report.

A 93-year-old woman was transferred to our hospital for lightheadedness. She had had Takotsubo cardiomyopathy for seven years. Transthoracic apical four-chamber echocardiography showed a large apical aneurysm. Pulsed-wave Doppler echocardiography at the left ventricular (LV) basal obstruction showed flow directed from the apex to the base during systole and isovolumic relaxation time. The patient was therefore diagnosed with mid-ventricular obstructive cardiomyopathy with a large apical aneurysm and paradoxical flow. The present case suggests that Takotsubo cardiomyopathy may become mid-ventricular obstructive hypertrophic cardiomyopathy without change in its structure.

Left ventricular systolic function in subjects conceived through assisted reproductive technologies.

Over the past decades, assisted reproductive technologies (ART) have gained remarkable influence in the treatment of infertility and account for more than 2 % of births in European countries nowadays. Accumulating evidence suggests ART to cause cardiovascular alterations, including left ventricular (LV) dysfunctions, within its offspring. The aim of this study was to assess LV systolic function in subjects conceived through ART in comparison to spontaneously conceived peers. For the assessment of LV morphology and LV function, M-Mode echocardiography, pulsed wave Doppler and two-dimensional speckle tracking echocardiography (2DSTE) were applied. LV ejection fraction (EF) and fractional shortening (FS) were assessed in M-Mode and calculated by Teichholz formula. EF was additionally assessed semiautomatically through 2DSTE. In total, 64 ART subjects and 83 spontaneously conceived controls with no significant differences in age (12.52 ± 5.64 years vs. 13.20 ± 5.95 years, p = 0.486) and sex were included in the analysis. In the ART cohort, significantly lower values were observed for M-Mode assessed EF (63.63 ± 5.17 % vs. 65.35 ± 5.10 %, p = 0.046) and FS (34.26 ± 3.87 % vs. 35.60 ± 3.84 %, p = 0.038). However, after the adjustment for birth weight percentile and gestational age, M-Mode assessed EF and FS displayed no significant differences between both groups. LV morphology and remaining systolic function parameters, such as mitral annular plane systolic excursion, aortic velocity time integral, global peak longitudinal strain and 2DSTE measured EF, were comparable between both groups. This study suggests a lower LV systolic function in ART subjects, visualized by significantly lower values for M-Mode assessed EF and FS, compared to spontaneously conceived peers. The clinical relevance of these findings has to be investigated as the above-mentioned parameters were in normal reference range. In addition, LV systolic function parameters evaluated by other echocardiographic imaging modalities were comparable between both groups. Therefore, further studies will be required to evaluate the influence of ART on LV systolic function and cardiovascular morbidity in the future.

Comparative assessment of coronary physiology using transthoracic pulsed-wave Doppler and myocardial contrast echocardiography in rats

BackgroundCoronary physiology assessment in rodents by ultrasound is an excellent noninvasive and easy to perform technique, including pulsed-wave Doppler (PWD) and myocardial contrast echocardiography (MCE). Both techniques and the corresponding calculated parameters were investigated in this study at rest as well as their response to pharmacologically induced stress.MethodsLeft ventricular myocardial function was assessed in eight anaesthetised rats using transthoracic echocardiography. Coronary physiology was assessed by both PWD of the left coronary artery and MCE using a bolus method. Measurements were performed at rest and under stimulation with adenosine and dobutamine. Effects of stimulation on the calculated parameters were evaluated and rated by effect size (η2).ResultsChanges could be demonstrated by selected parameters of PWD and MCE. The clearest effect in PWD was found for diastolic peak velocity (η2 = 0.58). It increased from 528 ± 110 mm/s (mean ± standard deviation) at rest to 839 ± 342 mm/s (p = 0.001) with adenosine and 1093 ± 302 mm/s with dobutamine (p = 0.001). The most distinct effect from MCE was found for the normalised wash-in rate (η2 = 0.58). It increased from 1.95 ± 0.35% at rest to 3.87 ± 0.85% with adenosine (p = 0.001) and 3.72 ± 1.03% with dobutamine (p = 0.001).ConclusionInduced changes in coronary physiology by adenosine and dobutamine could successfully be monitored using MCE and PWD in anaesthetised rats. Due to the low invasiveness of the measurements, this protocol could be used for longitudinal animal studies.

Abstract 12741: Effect of One Year of Exercise Training on Left Ventricular Relaxation in Patients With Stage B Heart Failure

Introduction: Left ventricular hypertrophy (LVH) is a risk factor for developing heart failure (HF). Exercise training decreases LV stiffness in individuals with LVH, but the effects of exercise training on LV relaxation in these individuals are unknown. Methods: Patients with LVH (&gt; 11 mm) and elevated cardiac biomarkers (N-terminal pro- B-type natriuretic peptide [&gt;40 pg/mL] or high-sensitivity troponin T [&gt;0.6 pg/mL]) were randomized 2:1 to 1 year of monitored exercise training 4-5 days a week, including high intensity intervals, and 1-2 days of strength training or an attention control. Isovolumetric relaxation time (IVRT) was measured with pulse wave Doppler echocardiography and pulmonary capillary wedge pressure (PCWP) was consecutively measured with right heart catheterization before and after intervention. LV relaxation time constant, Tau, was estimated by Tau = IVRT / (Ln End-systolic pressure (ESP) - Ln PCWP) (Figure). Maximal oxygen uptake (VO 2 Max; Douglas bags) was measured with an incremental treadmill test. LV Stiffness was significantly improved in exercise arm, previously reported. Results: Thirty-one participants completed the study (Control: n=11, 51±6 years, 55% men, Exercise: n=20 53±6, 65% men). VO 2 Max increased by 18.2% in the exercise arm (2.2±0.6 L/min to 2.5±0.6, but not in controls; group x time p&lt;0.001). Exercise training did not change Tau (exercise 38.2±6.5 to 39.8±8.7 ms) compared to control(40.3 ± 5.9 to 39.2±6.8 ms, group x time p = 0.84, Figure ). Exercise training resulted in no significant changes in IVRT (p = 0.35), SBP (p=0.89) or PCWP (p=0.69). Conclusions: In patients with LVH at risk for HF, one year of high intensity exercise training did not improve LV relaxation despite significant improvement in ventricular stiffness and exercise capacity. These results suggest the primary mechanism for HF risk reduction with exercise training is by lowering LV stiffness, and not necessarily altering LV relaxation.

Cardiac hemodynamics and ventricular stiffness of sea-run cherry salmon (Oncorhynchus masou masou) differ critically from those of landlocked masu salmon.

Ventricular diastolic mechanical properties are important determinants of cardiac function and are optimized by changes in cardiac structure and physical properties. Oncorhynchus masou masou is an anadromous migratory fish of the Salmonidae family, and several ecological studies on it have been conducted; however, the cardiac functions of the fish are not well known. Therefore, we investigated ventricular diastolic function in landlocked (masu salmon) and sea-run (cherry salmon) types at 29-30 months post fertilization. Pulsed-wave Doppler echocardiography showed that the atrioventricular inflow waveforms of cherry salmon were biphasic with early diastolic filling and atrial contraction, whereas those of masu salmon were monophasic with atrial contraction. In addition, end-diastolic pressure-volume relationship analysis revealed that the dilatability per unit myocardial mass of the ventricle in cherry salmon was significantly suppressed compared to that in masu salmon, suggesting that the ventricle of the cherry salmon was relatively stiffer (relative ventricular stiffness index; p = 0.0263). Contrastingly, the extensibility of cardiomyocytes, characterized by the expression pattern of Connectin isoforms in their ventricles, was similar in both types. Histological analysis showed that the percentage of the collagen accumulation area in the compact layer of cherry salmon increased compared with that of the masu salmon, which may contribute to ventricle stiffness. Although the heart mass of cherry salmon was about 11-fold greater than that of masu salmon, there was no difference in the morphology of the isolated cardiomyocytes, suggesting that the heart of the cherry salmon grows by cardiomyocyte proliferation, but not cell hypertrophy. The cardiac physiological function of the teleosts varies with differences in their developmental processes and life history. Our multidimensional analysis of the O. masou heart may provide a clue to the process by which the heart acquires a biphasic blood-filling pattern, i.e., a ventricular diastolic suction.

Reference Values and Repeatability of Pulsed Wave Doppler Echocardiography Parameters in Normal Donkeys.

Simple SummaryCardiovascular disease is underreported in donkeys, possibly related to their limited athletic posture and frequent poor performance-related examinations. Reports on treatments for cardiovascular disease are anecdotal in donkey. Normal echocardiographic parameters have been reported in healthy donkeys. The aim of the present study was to establish the reference values and repeatability for Pulsed Wave Doppler echocardiographic variables of the mitral valve, aortic valve and myocardial performance. Two-dimensional Color flow mapping and spectral Doppler modes were performed. For the mitral valve, the mean velocity, pressure gradient and duration of E-wave were 57.7 ± 12.5 cm/s, 1.4 ± 0.7 mmHg and 0.4 ± 0.13 s, respectively. The results of the present study provide the reference values of PW echocardiographic parameters measurements in normal adult donkeys. Such reference values are helpful, especially when confronted with clinical cases with cardiovascular disorders.In the present study, thirty clinically healthy donkeys were used to establish the reference values and repeatability for Pulsed Wave Doppler echocardiographic variables of the mitral valve, aortic valve and myocardial performance. 2-dimensional Color flow mapping and spectral Doppler modes were performed. For the mitral valve, the mean velocity, pressure gradient and duration of E-wave were 57.7 ± 12.5 cm/s, 1.4 ± 0.7 mmHg and 0.4 ± 0.13 s, respectively. The velocity, pressure gradient and duration of the A-wave were 32.3 ± 9.1 cm/s, 0.3 ± 0.04 mmHg and 0.3 ± 0.1 s, respectively. The mitral valve area, pressure half time, pulsatility index (PI), resistance index (RI) and velocity time integral (VTI) were 1.8 ± 0.5 cm2, 66 ± 17 ms, 2.8 ± 1.4, 0.9 ± 0.03 and 19.1 ± 5.7 cm, respectively. For the aortic valve, the mean velocity was 64.9 ± 10.4 cm/s, pressure gradient was 1.8 ± 0.4 mmHg, pulsatility index was 1.4 ± 0.3, resistance index was 0.9 ± 0.02, VTI was 25.02 ± 6.2 cm, systolic/diastolic was 19 ± 4.7 and heart rate was 95.7 ± 28.9 per minute. For Myocardial Performance Index (LV)–Tei Index, the mean ejection, isovolumic relaxation, isovolumic contraction time and myocardial performance index were 0.24 ± 0.01, 0.14 ± 0.01, 0.14 ± 0.02 and 1.2 ± 0.1 s, respectively. The results of the present study provide the reference values of PW echocardiographic parameter measurements in normal adult donkeys. Such reference values are helpful, especially when confronted with clinical cases with cardiovascular disorders.

Transthoracic Echocardiography to Assess Post-Resuscitation Left Ventricular Dysfunction After Acute Myocardial Infarction and Cardiac Arrest in Pigs

One of the main causes of out-of-hospital cardiac arrest is acute myocardial infarction (AMI). After successful resuscitation from cardiac arrest, approximately 70% of patients die before hospital discharge due to post-resuscitation myocardial and cerebral dysfunction. In experimental models, myocardial dysfunction after cardiac arrest, characterized by an impairment in both left ventricular (LV) systolic and diastolic function, has been described as reversible but very little data are available in cardiac arrest models associated with AMI in pigs. Transthoracic echocardiography is the first-line diagnostic test for the assessment of myocardial dysfunction, structural changes and/or AMI extension. In this pig model of ischemic cardiac arrest, echocardiography was done at baseline and 2-4 and 96 hours after resuscitation. In the acute phase, the examinations are done in anesthetized, mechanically ventilated pigs (weight 39.8 ± 0.6 kg) and ECG is recorded continuously. Mono- and bi-dimensional, Doppler and tissue Doppler recordings are acquired. Aortic and left atrium diameter, end-systolic and end-diastolic left ventricular wall thicknesses, end-diastolic and end-systolic diameters and shortening fraction (SF) are measured. Apical 2-, 3-, 4-, and 5-chamber views are acquired, LV volumes and ejection fraction are calculated. Segmental wall motion analysis is done to detect the localization and estimate the extent of myocardial infarction. Pulsed Wave Doppler echocardiography is used to record trans-mitral flow velocities from a 4-apical chamber view and trans-aortic flow from a 5-chamber view to calculate LV cardiac output (CO) and stroke volume (SV). Tissue Doppler Imaging (TDI) of LV lateral and septal mitral anulus is recorded (TDI septal and lateral s', e', a' velocities). All the recordings and measurements are done according to the recommendations of the American and European Societies of Echocardiography Guidelines.

Plasma Brain Natriuretic Peptide Levels in Children with Chronic Kidney Disease and Renal Transplant Recipients: A Single Center Study.

Pediatric chronic kidney disease (CKD) patients, as well as kidney transplant patients, are at an increased risk of developing cardiovascular disease. BNP measurement, as a biomarker of cardiovascular risk, has been recommended to this high-risk population. Plasma BNP levels were measured in 56 CKD children in either pre-dialysis stage, hemodialysis (HD) or renal transplant recipients (RTRs) and in 76 sex- and age-matched healthy controls. BNP levels were investigated in HD children, before and after the completion of their HD session. BNP levels in total CKD population, in pre-dialysis stage patients and on HD were significantly higher, compared to the respective controls. HD children had higher BNP levels compared to CKD patients in the pre-dialysis stage. Moreover, post-HD BNP concentration was slightly higher than pre-HD, with the difference being marginally statistically significant. BNP was positively correlated with eGFR, creatinine, cystatin-C and parathormone and negatively with albumin and 25-hydroxyvitamin D. A positive correlation between BNP concentration and the ratio of E/A in pulse-wave Doppler echocardiography was also observed. In conclusion, CKD pediatric patients, mainly those undergoing HD, have high plasma BNP levels which do not decrease after the HD session. This is indicative of a greater risk for future cardiovascular disease.

Early myocardial functional abnormalities in primary dyslipidemia: clinical and echocardiographic observations in young children from a highly consanguineous population.

Background Dyslipidemia is a major health problem among children and adolescents worldwide due to its significant association with cardiovascular disease. Primary dyslipidemias are commonly familial syndromes that can be completely asymptomatic.Purpose Apart from the risk of coronary artery disease (CAD), limited data are currently available on the direct effects of dyslipidemia on myocardial function in children.Methods We recruited 25 children with primary dyslipidemia (14 with isolated hypercholesterolemia, 4 with isolated hypertriglyceridemia, and 7 with combined dyslipidemia). Relevant clinical manifestations and laboratory and radiological investigations were evaluated. Pulsed-wave Doppler and tissue Doppler imaging echocardiography were performed for all recruited patients and the results were compared with those of 15 age- and sex-matched healthy children.Results The median age of the dyslipidemic children was 8 years (range, 1.5–16 years). A family history was documented in 13 cases (52%), while 18 (72%) had consanguineous parents. None of the dyslipidemic children had a personal history or clinical manifestations of CAD. In contrast, echocardiographic findings differed in several diastolic function parameters of both right and left ventricles in dyslipidemic children compared to controls. Based on normalized z scores, aortic valve narrowing was detected in 7 patients (28%), while narrowing of the aortic sinus (sinus of Valsalva) was detected in 15 patients (60%).Conclusion Different types of primary dyslipidemia produce functional myocardial abnormalities early in childhood. Biochemical and echocardiographic screening of high-risk children is advised to minimize the incidence of serious cardiovascular complications.

Studies on Pulsed-wave Doppler Echocardiography in Small Breed Dogs

Studies on Pulsed-wave Doppler Echocardiography in Small Breed Dogs

Cardiac functions in children with growth hormone deficiency: Effects of one year of GH replacement therapy

IntroductionChildren with Growth Hormone deficiency (GHD) are prone to heart dysfunction and, if left untreated, will result in marked cardiac dysfunction in adulthood. The aim was to evaluate the effect of GHD and growth hormone (GH) therapy on cardiac structure in children and adolescents, and to investigate the role of insulin like growth factor-1 (IGF-1) in this. MethodsM-mode, pulse-wave Doppler echocardiography and tissue Doppler imaging (TDI) were performed in 49 children with GHD who were divided into those with a peak GH response < 7 μg/L and 7–10 μg/L after two GH stimulation tests, aged 8–16 years at baseline and at six and 12 months after GH initiation, and 49 healthy peers. IGF-1 concentration was measured. ResultsAlthough the left ventricular end diastolic and systolic diameters in both GH deficient groups were significantly lower than controls (p < 0.01), both diameters increased significantly with one year of treatment and achieved normal values (p > 0.05). Using TDI in both two patients group revealed increased E/A, prolonged isovolumic relaxation time, shortened ejection time, and a significant increase in myocardial performance index compared to controls (p < 0.001). Significant improvement was observed in these parameters from the sixth month of GH treatment (p < 0.001), this improvement does not match parameters measured in healthy peers, even after one year of treatment in both patients group. (p < 0.001). No correlation was found between IGF-1 concentration and any echocardiographic parameter. ConclusionEchocardiographic parameters were similar in children with a GH peak < 7 μg/L and 7–10 μg/L. In TDI, both systolic and diastolic function was impaired in GHD children compared to controls. These parameters improved after one year of GH therapy but did not recover to healthy control levels.

Left ventricular dysfunction and cardiac autonomic imbalance in children with drug-resistant epilepsy

BackgroundResistance to antiepileptic drug treatment increases the risk of comorbidities and mortality due to a cardio-autonomic imbalance and left ventricular (LV) dysfunction. ObjectiveTo assess the prevalence of LV dysfunction and cardio-autonomic imbalance in children with drug-resistant epilepsy (DRE). Patients and methodsThis cross-sectional study included 40 children with DRE and 40 healthy age- and sex-matched controls. LV function was evaluated by M-mode, two-dimensional, pulse-wave Doppler echocardiography, and tissue Doppler imaging (TDI). Cardio-autonomic function was assessed by 24 -h Holter monitoring of heart rate variability. ResultsAll time domain measures were significantly lower in the epilepsy group than in the control group (all Ps<0.01). Additionally, the mean high frequency (HF) parameters were significantly lower (P = 0.035), whereas the mean low frequency (LF) parameters and the LF/HF ratio were significantly higher (P < 0.001) in the epilepsy group than in the control group. LV function did not differ between groups regarding all standard echocardiographic parameters. There was evidence of subclinical LVdysfunction by tissue doppler among the epileptic group, as evidenced by the elevated Myocardial Performance Index, isovolumetric relaxation time and mitral E/Em ratio. There was no significant correlation between the duration of epilepsy or seizure frequency with any cardiac abnormality. ConclusionsChildren with DRE exhibited cardio-autonomic and subclinical LV dysfunction, independent of the duration of epilepsy, frequency, and seizure type.

Nifedipine disturbs fetal cardiac function during hypoxemia in a chronic sheep model at near term gestation

Nifedipine is a widely used drug in pregnancies complicated by maternal hypertensive disorders that can be associated with placental insufficiency and fetal hypoxemia. The evidence regarding fetal myocardial responses to nifedipine in hypoxemia is limited. We hypothesized that nifedipine would not impair fetal sheep cardiac function under hypoxemic environment. In particular, we investigated the effects of nifedipine on fetal ventricular functional parameters and cardiac output. A total of 21 chronically instrumented fetal sheep at 122 to 134 gestational days (term, 145 days) were included in this study. Fetal cardiac function was evaluated by measuring global longitudinal strain, indices describing ventricular systolic and diastolic function, and cardiac outputs using two-dimensional speckle tracking and tissue and spectral pulsed-wave Doppler echocardiography. Fetal carotid artery blood pressure and blood gas values were invasively monitored. After baseline data collection, fetal hypoxemia was induced by maternal hyperoxygenation. After hypoxemia phase data collection, 9 fetuses received nifedipine infusion, and 12 fetuses received saline infusion. Data were collected 30 and 120 minutes after the infusion was started. After 120 minutes of data collection, maternal and fetal oxygenation were normalized, and normoxemia phase data were collected, while infusion was continued. Hypoxemia decreased fetal carotid artery mean arterial pressure from 40 (8) mm Hg to 35 (8) mm Hg (P<.007), and left ventricular global longitudinal strain showed less deformation than at baseline (P=.001). Under hypoxemia, nifedipine caused a reduction in right ventricular global longitudinal strain (P<.05), a decrease in right ventricular isovolumic relaxation velocity and its deceleration (P<.01) indicating diastolic dysfunction, and a drop in right ventricular cardiac output (P<.05). Nifedipine did not alter fetal left ventricular functional parameters or cardiac output. When normoxemia was restored, fetal right ventricular functional parameters and cardiac output returned to baseline level. In hypoxemic fetus, nifedipine impaired right ventricular function and reduced its cardiac output. The detrimental effects of nifedipine on fetal right ventricular function were abolished, when normoxemia was restored. Our findings suggest that in a hypoxemic environment nifedipine triggers detrimental effects on fetal right ventricular function.

Coronary Flow Reserve Predicts Major Adverse Cardiac Events and All-Cause Mortality in Heart Transplant Recipients

<h3>Purpose</h3> Cardiac allograft vasculopathy (CAV) after heart transplantation (HTx) affects the epicardial arteries and veins and also the coronary microcirculation. In the absence of proximal epicardial artery stenosis, coronary flow velocity reserve (CFVR) reflects the function of the myocardial microcirculation. We aimed to determine the prognostic value of 1) CFVR and 2) a combination of CFVR and left ventricular global longitudinal strain (LVGLS) in HTx patients. <h3>Methods</h3> CFVR was evaluated using pulsed wave Doppler echocardiography in 98 HTx patients (median 6.9 years from HTx) examined with coronary angiography. Patients were enrolled from 2013 to 2018 and prospectively followed until June 1^st 2020. All-cause mortality and major adverse cardiac events (MACE) including heart failure, significant CAV progression, coronary intervention or cardiovascular death, were recorded. <h3>Results</h3> Median follow-up was 3.2 [interquartile range 1.9-5.1] years. Patients with low CFVR (<2.0, n=20) had a significantly reduced event-free survival rate compared with patients with high CFVR (≥2.0, n=78) (35% vs. 82%, hazard ratio (HR) 4.6, 95% CI 2.3-9.1, <i>p</i><0.0001) and had a higher rate of mortality than patients with high CFVR with an absolute difference of 43.3% (65.3% vs. 22.0%; HR 5.0, 95% CI 2.1-11.9, <i>p</i><0.0001). By combining low CFVR and low LVGLS magnitude (>-15.5%), we obtained a strong predictive model for MACE (HR 10.5, 95% CI 4.5-24.5, <i>p</i><0.0001) and all-cause mortality (HR 10.3, 95% CI 3.5-30.6, <i>p</i><0.001), which remained strong after adjustment for angiographic CAV. <h3>Conclusion</h3> CFVR strongly predicts MACE and all-cause mortality in HTx-patients. A model combining low CFVR and low LVGLS magnitude was a strong model for MACE and all-cause mortality prediction and could be considered as a non-invasive method for routine CAV surveillance.

Triphasic Mitral Inflow Pattern

A 73-YEAR-OLD woman (weight 84.8 kg, height 152 cm) was scheduled to undergo a percutaneous transcatheter aortic valve replacement for severe aortic stenosis eight years after bioprosthetic aortic valve replacement. Her medical history was notable for hypertension, diabetes mellitus, atrial fibrillation, hypercholesterolemia, and coronary artery disease. Transthoracic echocardiography showed left ventricular (LV) hypertrophy and an ejection fraction of 73%. The waveform in Fig 1 was obtained during intraoperative interrogation of the mitral valve with pulse-wave Doppler echocardiography. What is the diagnosis?

Studies on Pulsed-wave Doppler Echocardiographic Parameters of Blood Flow through Mitral, Tricuspid and Aortic Valves in Healthy Indian Spitz Dogs

Background: Pulsed-wave Doppler measures blood flow at specific point and provides information on velocity, direction and uniformity of blood flow throughout cardiac cycle. Till date, there is no published data on study of cardiac parameters using pulsed-wave Doppler echocardiography in Indian Spitz dogs.Methods: Twenty-four clinically normal Indian Spitz dogs were subjected to pulsed-wave Doppler echocardiography to determine the reference intervals for Doppler parameters of blood flow through mitral, tricuspid and aortic valves. Mitral peak E and A-wave velocities, E/A ratio, deceleration time, isovolumic relaxation time, E and A-wave velocity time integral, E duration and A duration were 0.69±0.09 m/s, 0.43±0.12 m/s, 1.69±0.45, 111.25±35.94 ms, 48.50±24.77 ms, 0.07±0.01 m and 0.04±0.02 m, 196.88±44.38 ms and 181.25±64.89 ms, respectively. Tricuspid peak E and A-wave velocities, E/A ratio and E and A-wave velocity time integral were 0.57±0.11 m/s, 0.38±0.08 m/s, 1.56±0.32 and 0.07±0.02 m and 0.05±0.01 m, respectively. Aortic peak velocity, velocity time integral and ejection time were 0.87±0.07 m/s, 0.11±0.02 m and 0.25±0.04 s, respectively. Conclusion: The reference values of flow parameters across mitral, tricuspid and aortic valves using pulsed-wave Doppler echocardiography were determined. Mitral, tricuspid and aortic valve flow variables were unaffected by gender whereas isovolumic relaxation correlated positively with body weight.

Normative Reference Values of Cardiac Output by Pulsed-Wave Doppler Echocardiography in Adults

Cardiac output (CO) is routinely assessed by pulsed-wave Doppler echocardiography, yet reference values in adults are lacking. We aim to establish normative values of CO and cardiac index (CI) by pulsed-wave Doppler-echocardiography and to analyze their relation with gender and age in nonobese and obese adults. We included 4,040 adults (mean age: 55 years, 53% women, 950 obese [body mass index ≥30 kg/m²]) with normal blood pressure, no history of cardiovascular disease, and normal transthoracic echocardiography. Normative reference CO and CI values for were calculated in 3,090 nonobese patients by quantile regression. CO normal limits were lower in females than in males (lower limit: 3.3 vs 3.5 L/min, upper limit: 7.3 vs 8.2 L/min). CI normal limits were identical for both genders (lower limit: 1.9 L/min/m², upper limit: 4.3 L/min/m²). Although the relation of CO to age was weak and observed only in women, CI of both genders was not influenced by age. CO of obese patients was significantly greater than that of their nonobese counterparts. CI of obese patients was not influenced by age and gender and was not significantly different than that of nonobese patients (lower limit 1.8 L/min/m², upper limit 4.1 L/min/m² for both genders). In conclusion, in a large adult population we establish normative reference values for CO and CI measured by Doppler-echocardiography. CI is a remarkably stable parameter that is not influenced by age, gender, and body size and should be used to define low- and high-output states.