Evaluation of left ventricular diastolic function when mitral E and A waves are completely fused: role of assessing mitral annulus velocity

Assessing Complex Left Ventricular Adaptations in Aortic Stenosis Using Personalized 3D + time Cardiac MRI Modeling

Left ventricular adaptations can be a complex process under the influence of aortic stenosis (AS) and comorbidities. This study proposed and assessed the feasibility of using a motion-corrected personalized 3D + time LV modeling technique to evaluate the adaptive and maladaptive LV response to aid treatment decision-making. A total of 22 AS patients were analyzed and compared against 10 healthy subjects. The 3D + time analysis showed a highly distinct and personalized pattern of remodeling in individual AS patients which is associated with comorbidities and fibrosis. Patients with AS alone showed better wall thickening and synchrony than those comorbid with hypertension. Ischemic heart disease in AS caused impaired wall thickening and synchrony and systolic function. Apart from showing significant correlations to echocardiography and clinical MRI measurements (r: 0.70-0.95; p < 0.01), the proposed technique helped in detecting subclinical and subtle LV dysfunction, providing a better approach to evaluate AS patients for specific treatment, surgical planning, and follow-up recovery.

Echocardiographic Evaluation of Diastolic Function in Special Populations

Left ventricular (LV) diastolic dysfunction results from a combination of impaired relaxation, reduced restoring forces, and increased chamber stiffness. Noninvasive assessment of diastology uses a multiparametric approach involving surrogate markers of increased filling pressures, which include mitral inflow, septal and lateral annular velocities, tricuspid regurgitation velocity, and left atrial volume index. However, these parameters must be used cautiously. This is because the traditional algorithms for evaluating diastolic function and estimation of LV filling pressures (LVFPs), as recommended by the American Society of Echocardiography and European Association of Cardiovascular Imaging 2016 guidelines, do not apply to unique patients with underlying cardiomyopathies, significant valvular disease, conduction abnormalities, arrhythmias, LV assist devices, and heart transplants, which alter the relation between the conventional indexes of diastolic function and LVFP. The purpose of this review is to provide solutions for evaluating LVFP through illustrative examples of these special populations, incorporating supplemental Doppler indexes, such as isovolumic relaxation time, mitral deceleration time, and pulmonary venous flow analysis, as needed to formulate a more comprehensive approach.

Associations between Subclinical Myocardial Dysfunction and Premature Fusion of Early and Late Diastolic Filling with Uncertain Cause

PURPOSE

The fusion of early (E) and late diastolic filling (A) on mitral inflow Doppler, even in the absence of tachycardia, is often found during assessment of left ventricular (LV) diastolic function. We evaluated the echocardiographic characteristics and clinical implications of premature E-A fusion of uncertain cause in the absence of tachycardia.

MATERIALS AND METHODS

We identified 1014 subjects who showed E-A fusion and normal LV ejection fraction (LVEF) between January 2019 and June 2021 at two tertiary hospitals. Among these, 105 (10.4%) subjects showed premature E-A fusion at heart rates less than 100 beats per minute (bpm). The conventional echocardiographic parameters and LV global longitudinal strain (GLS) were compared with 1:1 age-, sex-, and heart rate-matched controls without E-A fusion.

RESULTS

The premature E-A fusion group had a heart rate of 96.4±3.7 bpm. Only 4 (3.8%) subjects were classified as having LV diastolic dysfunction according to current guidelines. The group showed prolonged isovolumic relaxation time (107.2±25.3 msec vs. 61.6±15.6 msec, p<0.001), increased Tei index (0.76±0.19 vs. 0.48±0.10, p<0.001), lower LVEF (63.8±7.0% vs. 67.3±5.6%, p<0.001) and lower absolute LV GLS (|LV GLS|) (17.0±4.2% vs. 19.7±3.3%, p<0.001) than controls. As the E-A fusion occurred at lower heart rate, the |LV GLS| was also lower (p for trend=0.002).

CONCLUSION

Premature E-A fusion at heart rates less than 100 bpm is associated with subclinical LV dysfunction. Time-based indices and LV GLS are helpful for evaluating this easily overlooked population.

Cardiorespiratory Abnormalities in Patients Recovering from Coronavirus Disease 2019

Background

A large number of patients around the world are recovering from coronavirus disease 2019 (COVID-19); many of them report persistence of symptoms. The aim of this study was to test pulmonary, cardiovascular, and peripheral responses to exercise in patients recovering from COVID-19.

Methods

Patients who recovered from COVID-19 were prospectively evaluated using a combined anatomic and functional assessment. All patients underwent clinical examination, laboratory tests, and combined stress echocardiography and cardiopulmonary exercise testing. Left ventricular volumes, ejection fraction, stroke volume, heart rate, E/e′ ratio, right ventricular function, oxygen consumption (Vo₂), lung volumes, ventilatory efficiency, oxygen saturation, and muscle oxygen extraction were measured in all effort stages and compared with values in historical control subjects.

Results

A total of 71 patients were assessed 90.6 ± 26 days after the onset of COVID-19 symptoms. Only 23 (33%) were asymptomatic. The most common symptoms were fatigue (34%), muscle weakness or pain (27%), and dyspnea (22%). Vo₂ was lower among post-COVID-19 patients compared with control subjects (P = .03, group-by-time interaction P = .007). Reduction in peak Vo₂ was due to a combination of chronotropic incompetence (75% of post-COVID-19 patients vs 8% of control subjects, P < .0001) and an insufficient increase in stroke volume during exercise (P = .0007, group-by-time interaction P = .03). Stroke volume limitation was mostly explained by diminished increase in left ventricular end-diastolic volume (P = .10, group-by-time interaction P = .03) and insufficient increase in ejection fraction (P = .01, group-by-time interaction P = .01). Post-COVID-19 patients had higher peripheral oxygen extraction (P = .004) and did not have significantly different respiratory and gas exchange parameters compared with control subjects.

Conclusions

Patients recovering from COVID-19 have symptoms associated with objective reduction in peak Vo₂. The mechanism of this reduction is complex and mainly involves a combination of attenuated heart rate and stroke volume reserve.

Carotid-femoral pulse wave velocity is significantly increased in newly diagnosed hypertensive patients with primary hyperparathyroidism and significantly related with serum calcium level

BACKGROUND

Primary hyperparathyroidism (PHP) is a rare cause of secondary hypertension (HT), but in patients with PHP, HT is very common and 20-80% of patients have HT. The aim of this study was to evaluate the change in carotid-femoral pulse wave velocity (CF-PWV) in hypertensive patients with PHP, and was to determine the clinical, laboratory, and echocardiographic parameters associated with CF-PWV.

METHODS

The study included 83 newly diagnosed hypertensive patients with PHP and 83 patients with newly diagnosed essential HT without PHP. All patients underwent echocardiography and CF-PWV measurements.

RESULTS

In patients with PHP, blood urea nitrogen, hs-CRP, uric acid, serum and urine calcium, parathyroid hormone level, CF-PWV value, LV wall thickness, LVMI, aortic and left atrium (LA) diameter, and presence of LVH and CF-PWV > 10 m/s were higher, and serum phosphorus levels were lower. Serum calcium, LA diameter, and LVMI values were closely correlated with CF-PWV. In the ROC analysis, the AUROC was calculated as 0.825 for calcium level to determine the patients with increased CF-PWV. When the serum calcium value was taken as 10 mg/dL, it was determined with CF-PWV > 10 m/s were 79.5% sensitivity and 78.2% specificity.

CONCLUSION

CF-PWV significantly increases in newly diagnosed hypertensive patients with PHP and significantly related to serum calcium level. To protect against target organ damage, high serum calcium levels should be monitored as well as blood pressure in hypertensive patients with PHP.

Renal resistive index significantly increased in hypertensive children and it is independently related to the pulse pressure and left ventricular mass index

Background: To the best our knowledge there is no data in the literature related to changes in renal resistive index (RRI) values in children who have hypertension (HT). In this study, we aimed to investigate the changes of RRI values and it is usability in children with HT. Methods: A total of 75 children; 48 with newly diagnosed HT and 27 healthy controls were included in the study. Routine history, physical examination, and laboratory examinations were performed. Left ventricular (LV) dimensions and systolic-diastolic functions, septum and posterior wall thickness (IVSd and PWd) and LV mass index (LVMI) were calculated by echocardiography. In addition to routine renal ultrasonography (US), renal pulsatility indexes (RPI), accelerated time and RRI were measured. Increased RRI was accepted as >0.70. Results: Increased RRI was detected in 25 (52%) of HT patients. Systolic and diastolic blood pressure (SBP and DBP), and pulse pressure (PP), low-density lipoprotein cholesterol and triglyceride levels, RRI, RPI, kidney length, IVSd, PWd, and LVMI were significantly higher in patients with HT (both p < 0.05). SBP and PP, PWd, LV ejection fraction, LV fractional shortening, and LVMI were positively correlated with the RRI. High-density lipoprotein cholesterol was negatively correlated with the RRI. Of these measurements, RRI values were found to be independently associated with PP and LVMI (p < 0.05). Conclusions: In hypertensive children, RRI was significantly higher than healthy controls and it is also related with LVMI and PP.

Carotid sinus massage in the echocardiography laboratory

Proper interpretation of the spectral Doppler signal and elucidation of the underlying hemodynamics can at times be problematic due to confounding factors, one of them being a rapid heart rate. In this article, we discuss the use of carotid sinus massage (CSM) in the echocardiography laboratory as a maneuver to reduce the resting heart rate and thus render the transmitral Doppler signal more amenable to analysis. We provide examples of the value of the CSM in the assessment of left ventricular filling pressure.

Diastolic heart failure: a concise review

The concept of “diastolic” heart failure grew out of the observation that many patients who have the symptoms and signs of heart failure had an apparently normal left ventricular (LV) ejection fraction. Thus it was assumed that since systolic function was “preserved” the problem must lie in diastole, although it is not clear by whom or when this assumption was made. Nevertheless, many guidelines followed on how to diagnose “diastolic” heart failure backed up by indicators of diastolic dysfunction derived from Doppler echoardiography. Diastolic heart failure is associated with a lower annual mortality rate of approximately 8% as compared to annual mortality of 19% in heart failure with systolic dysfunction, however, morbidity rate can be substantial. Thus, diastolic heart failure is an important clinical disorder mainly seen in the elderly patients with hypertensive heart disease. Early recognition and appropriate therapy of diastolic dysfunction is advisable to prevent further progression to diastolic heart failure and death. There is no specific therapy to improve LV diastolic function directly. Medical therapy of diastolic dysfunction is often empirical and lacks clear-cut pathophysiologic concepts. Nevertheless, there is growing evidence that calcium channel blockers, beta-blockers, ACE-inhibitors and ARB as well as nitric oxide donors can be beneficial. Treatment of the underlying disease is currently the most important therapeutic approach.

Is myocardial performance index useful in differential diagnosis of moderate and severe hypoxic-ischaemic encephalopathy? A serial Doppler echocardiographic evaluation

INTRODUCTION

The aim of this study was to investigate the importance of myocardial performance index as an additive criterion to Sarnat criteria in differential diagnosis of newborn babies with moderate and severe hypoxic-ischaemic encephalopathy.

METHODS

Our study group included 50 healthy term newborn babies and 20 newborn babies with hypoxic-ischaemic encephalopathy. The 20 newborn babies with hypoxic-ischaemic encephalopathy were scored using Sarnat grades. Left and right ventricular functions were determined on the first day and thereafter in the 1, 3-4, 6-7, and 11-12 months of life by M-Mode and pulsed Doppler.

RESULTS

Myocardial performance indexes of the left ventricle were significantly higher in the severe hypoxic-ischaemic encephalopathy group than in the control group during the first, second, and third analyses (p = 0.01, p = 0.02, p = 0.02, respectively) and only during the first analysis (p = 0.01) in the moderate hypoxic-ischaemic encephalopathy group. In addition, the myocardial performance indexes of the right ventricle were significantly higher during the first, second, and third analyses in both severe and moderate hypoxic-ischaemic encephalopathy groups than in the control group (p = 0.01, all). Hypoxia-induced alterations last longer in the right ventricle than in the left ventricle in the moderate group, as during the second and third analyses myocardial performance index continues to be higher than the control group.

CONCLUSION

Myocardial performance indexes for the left and right ventricles were significantly higher in both severe and moderate hypoxic-ischaemic encephalopathy groups than in the control group during the first analysis, and myocardial performance index greater than or equal to 0.5 can be used in order to distinguish moderate and severe hypoxic-ischaemic encephalopathy babies according to Sarnat grades as a discriminative additive criterion.

Perioperative assessment of diastolic dysfunction

Assessment of diastolic function should be a component of a comprehensive perioperative transesophageal echocardiographic examination. Abnormal diastolic function exists in >50% of patients presenting for cardiac and high-risk noncardiac surgery, and has been shown to be an independent predictor of adverse postoperative outcome. Normalcy of systolic function in 50% of patients with congestive heart failure implicates diastolic dysfunction as the probable etiology. Comprehensive evaluation of diastolic function requires the use of various, load-dependent Doppler techniques This is further complicated by the additional effects of dehydration and anesthetic drugs on myocardial relaxation and compliance as assessed by these Doppler measures. The availability of more sophisticated Doppler techniques, e.g., Doppler tissue imaging and flow propagation velocity, makes it possible to interrogate left ventricular diastolic function with greater precision, analyze specific stages of diastole, and to differentiate abnormalities of relaxation from compliance. Additionally, various Doppler-derived ratios can be used to estimate left ventricular filling pressures. The varying hemodynamic environment of the operating room mandates modification of the diagnostic algorithms used for ambulatory cardiac patients when left ventricular diastolic function is evaluated with transesophageal echocardiography in anesthetized surgical patients.

WEB downloadable software for training in cardiovascular hemodynamics in the (3-D) stress echo lab

When a physiological (exercise) stress echo is scheduled, interest focuses on wall motion segmental contraction abnormalities to diagnose ischemic response to stress, and on left ventricular ejection fraction to assess contractile reserve. Echocardiographic evaluation of volumes (plus standard assessment of heart rate and blood pressure) is ideally suited for the quantitative and accurate calculation of a set of parameters allowing a complete characterization of cardiovascular hemodynamics (including cardiac output and systemic vascular resistance), left ventricular elastance (mirroring left ventricular contractility, theoretically independent of preload and afterload changes heavily affecting the ejection fraction), arterial elastance, ventricular arterial coupling (a central determinant of net cardiovascular performance in normal and pathological conditions), and diastolic function (through the diastolic mean filling rate). All these parameters were previously inaccessible, inaccurate or labor-intensive and now become, at least in principle, available in the stress echocardiography laboratory since all of them need an accurate estimation of left ventricular volumes and stroke volume, easily derived from 3 D echo.

Aims of this paper are: 1) to propose a simple method to assess a set of parameters allowing a complete characterization of cardiovascular hemodynamics in the stress echo lab, from basic measurements to calculations 2) to propose a simple, web-based software program, to learn and training calculations as a phantom of the everyday activity in the busy stress echo lab 3) to show examples of software testing in a way that proves its value.

The informatics infrastructure is available on the web, linking to http://cctrainer.ifc.cnr.it

Prognostic value of tissue Doppler-Derived E/e' on early morbid events after cardiac surgery

BACKGROUND

The tissue Doppler-derived surrogate for left ventricular diastolic pressure, E/e', has been used to prognosticate outcome in a variety of cardiovascular conditions. In this study, we determined the relationship of intraoperative E/e' to the use of inotropic support, duration of mechanical ventilation (MV), length of intensive care unit stay (ICU-LOS), and total hospital stay (H-LOS) in patients requiring cardiac surgery. The records of 245 consecutive patients were retrospectively reviewed to obtain 205 patients who had intraoperative transesophageal echocardiography examinations prior to coronary artery bypass grafting and/or valvular surgery. Cox proportional hazards and logistic regression models were used to analyze the relation between intraoperative E/e' or LVEF and early postoperative morbidity (H-LOS, ICU-LOS, and MV) and the probability that a patient would require inotropic support. With adjustments for other predictors (female gender, hypertension, diabetes, history of myocardial infarction, emergency surgery, renal failure, procedure type, and length of aortic cross-clamp time), an elevated E/e' ratio (>or=8) was significantly associated with an increased ICU-LOS (49 versus 41 median h, P = 0.037) and need for inotropic support (P = 0.002) while baseline LVEF was associated with inotropic support alone (P < 0.0001). These data suggest that the tissue Doppler-derived index of left ventricular diastolic filling pressure may be a useful indicator for predicting early morbid events after cardiac surgery, and may even provide additional information from that of baseline LVEF. Further, patients with elevated preoperative E/e' may need more careful peri- and postoperative management than those patients with E/e' <8.

Echocardiographic examination in rats and mice

Rats and mice are the predominant experimental species in cardiovascular research due to the widespread availability of genetic and transgenic rodent models of heart disease. Phenotyping of these models requires reliable and reproducible methods to noninvasively and serially assess cardiovascular structure and function. However, the small size of rodents has presented a challenge. Many of these challenges have been overcome in recent years due to significant technological advances in echocardiographic capabilities. For example, improved spatial resolution and increased frame rates have allowed more precise and accurate quantification of diminutive structures, myocardial function, and blood flow in mice. Consequently, transthoracic echocardiography (TTE) has emerged as a popular and powerful tool for cardiac phenotypic characterization in rodents. This chapter will focus on the use of TTE in rodents for evaluating (1) left ventricular (LV) chamber dimensions and wall thickness, (2) LV mass, (3) global LV systolic and diastolic function, (4) regional LV systolic function by newly developed tissue Doppler imaging (TDI), and (5) hemodynamic parameters. Reliability of these measurements depends on various factors such as the skill and experience of the sonographer and the image analyzer, the type, depth, and duration of anesthesia, and animal characteristics. These topics will also be discussed.

Annular and Septal Doppler Tissue Imaging in Children: Normal z-Score Tables and Effects of Age, Heart Rate, and Body Surface Area

The aim of this study was to construct normal z-score tables for longitudinal directed Doppler tissue imaging (DTI) systolic wave (S), DTI early diastolic wave (E'), and DTI late diastolic wave (A') at the mitral valve annulus (MV), superior ventricular septum (VS), and tricuspid valve annulus (TV) in pediatric patients. We analyzed normal echocardiograms from 634 children aged 1 day to 18 years, heart rate (HR) range of 50 to 194/min, and body surface area (BSA) range of 0.1 to 2.8 m2. First we determined the effects of age, HR, and BSA on the S, E', and A' at the MV, VS, and TV sampling sites by univariate analysis. Next we determined which of the 3 factors, age versus HR versus BSA, correlated best with the S, E', and A' at each of the 3 sampling sites by multivariate analysis. Finally, using the specific factor of age versus HR versus BSA that best predicted a particular DTI wave at a particular sampling site, we constructed z-score tables for each of the 3 DTI parameters at each of the 3 sampling sites. The S range was: MV = 2.2 to 23.2 cm/s; VS = 1.6 to 22.3 cm/s; and TV = 1.8 to 31.3 cm/s. By univariate analysis the S correlated negatively with HR and positively with age and BSA with strong correlations at all 3 sites. By multiple regression analysis the S correlated best with age at all 3 sites. The E' range was: MV = 2.4 to 37.1 cm/s; VS = 1.8 to 29.0 cm/s; and TV = 2.4 to 32.4 cm/s. The E' varied negatively with HR and positively with age and BSA with strong correlations by univariate analysis at all 3 sites. By multiple regression, the E' correlated best with age for the VS and TV sites, and correlated best with HR at the MV site. The E' at the MV site also strongly correlated with age by multivariate analysis. The A' range was: MV = 2.9 to 20.7 cm/s; VS = 2.7 to 18.2 cm/s; and TV = 1.1 to 29.3 cm/s. The A' had a strong positive correlation with HR at all 3 sites, a strong negative correlation with BSA and age at the TV site only, with no statistical significant correlation of the MV and VS site A' to BSA or age. Using multiple regression analysis the A' correlated best with HR at all 3 sites. Z-score tables developed from a large sample volume encompassing the entire spectrum of ages, HR, and BSA encountered in pediatric patients and developed using the strongest predicting factor serve as reference data for longitudinal directed DTI annular and septal S, E', and A' normal values in children.

Left ventricle diastolic function in the patients after coronary arteries bypass graft combined with left ventricle aneurismectomy according to tissue doppler imaging: one year follow-up

AIM

To evaluate left ventricle (LV) diastolic function dynamics in patients after acute myocardial infarction (AMI) after combined operation of coronary artery bypass graft with LV aneurismectomy (CABG + AE) according to the results of tissue Doppler imaging (TDI).

METHODS

Forty patients after AMI underwent Doppler echocardiography (EchoCG) with TDI and M-mode colour-flow imaging before and in 3 and 12 months after CABG + AE. Mitral annulus (MA) TDI with velocity indices was performed in 4 segments of LV.

RESULTS

Conventional transmitral diastolic Doppler indices before and after CABG + AE remained unchanged. TDI showed significant improvement of LV systolic (systolic movement velocity S: 6.1+/-0.8, 7.4+/-1.2 and 6.9+/-1.3 cm/sec. before and in 3 and 12 months after the operation, respectively, p<0.01) and diastolic function after the operation (MA early diastolic movement velocity (e'): 7.3 +/- 2.1, 8.4 +/- 1.5 and 8.9 +/- 1.8 cm/s.; ratio of transmitral early-flow velocity (E) to MA early-diastolic movement velocity (E/e'): 18.4 +/- 2.2, 12.3 +/- 1.8 and 11.5 +/- 2.3; ratio of E diastolic flow propagation velocity (Vp) 3.1 +/- 0.45, 2.2 +/- 0.38 and 1.8 +/- 0.16 before and in 3 and 12 months after the operation, respectively, p<0.01).

CONCLUSIONS

Results of the study demonstrate significant improvement of LV diastolic function in the patient after CABG + AE according to TDI, regardless of transmitral flow pattern. TDI is more sensitive and preload independent method of LV myocardial function evaluation.

Impact of mitral E/A ratio on the accuracy of different echocardiographic indices to estimate left ventricular end-diastolic pressure

The objective was to determine the influence of left ventricular (LV) inflow pattern on the accuracy of different echocardiographic indices for estimation of LV end-diastolic pressure (LVEDP). Echocardiography with color tissue Doppler imaging (TDI) and LVEDP measurements using fluid-filled catheters were performed in 176 consecutive patients on the same day. Mitral peak diastolic velocities (E, A) and the difference in duration between pulmonary venous retrograde velocity and mitral A-velocity (PV(R)-A) were recorded by pulsed Doppler. Propagation velocity of the early mitral inflow (V(P)) was assessed using color M-mode. Early diastolic longitudinal (E'(lat)) and radial (E'(radial)) velocities of mitral annulus were measured by TDI. Area under ROC curve (AUC) for prediction of elevated LVEDP (> or =15 mm Hg) was computed for each parameter. For E/A > or =1 (98 patients, 46 with elevated LVEDP), the AUC values were: PV(R)-A: 0.914; E/E'(lat): 0.780; E/E'(radial): 0.729; E/V(P): 0.712 (p < 0.001). When E/A <1 (78 patients, 26 with elevated LVEDP), only PV(R)-A reached statistical significance (AUC = 0.893, p < 0.001). The conclusions were: PV(R)-A enabled the most accurate noninvasive estimation of LVEDP irrespective of LV filling profile and combined indices E/V(P), E/E'(lat) and E/E'(radial) represent more feasible alternatives for patients with mitral E/A-1.

Diastolic performance assessed by tissue Doppler after pediatric heart transplantation

BACKGROUND

Diastolic performance, indexed by tissue Doppler imaging (TDI), has been reported to predict cellular rejection in adult heart recipients, but the predictive value of TDI after pediatric heart transplantation is unknown.

METHODS

TDI-derived diastolic performance was studied in 37 pediatric (median age 2.54 years) heart recipients in the absence and presence of rejection. Maximum velocities in diastole of the left ventricular posterior wall thinning (diastvelLVPWmax) and medial mitral valve annulus (MVA) were determined in 160 echocardiograms from recipients who experienced either no rejection (Group 1, n = 22) or >or=1 rejection episode(s) (Group 2, n = 14) during the study interval (2 years). There was 1 death in the immediate post-transplant period not included in the analyses.

RESULTS

The diastvelLVPWmax determined by TDI in Group 1 increased during the first 90 days post-transplant (r = 0.31; p = 0.05), was heart-rate-dependent (r = 0.591; p < 0.001), and was significantly lower than the veILVPWmax determined from digitized M-mode tracings (116 +/- 31 vs 135 +/- 44 mm/s; p < 0.05). In a sub-group of children transplanted during the study and followed for >or=1 year (n = 9), diastvelLPWmax, determined by TDI, was lower in infant recipients (n = 6; 106.5 +/- 22 mm/s) than in older recipients (n = 3; 135 +/- 36 mm/s; p = 0.015). With rejection, diastvelLVPWmax, determined by M mode (147 +/- 13 vs 104 +/- 11 mm/s; p < 0.05), was decreased compared with baseline recipient studies prior to rejection. In contrast, rejection did not significantly change diastvelLVPWmax, as determined by TDI. MVA E/A (peak early-to-late diastolic velocity ratio) was significantly decreased with rejection (1.37 +/- 0.23 vs 0.92 +/- 0.22; p < 0.05). As a single parameter, an MVA E/A <1.1 was predictive of rejection in 4 of 10 recipients with MVA E/A >or=1.1 pre-rejection.

CONCLUSIONS

TDI-derived diastvelLVPWmax varied with age at transplant, heart rate and time post-transplant. A decrease in TDI-derived MVA E/A, but not diastvelLVPWmax, can be of additional predictive value in non-invasive surveillance for rejection in pediatric heart recipients.

Clinical validity of measuring time difference between onset of mitral inflow and onset of early diastolic mitral annulus velocity in the evaluation of left ventricular diastolic function

OBJECTIVES

This study was performed to validate the clinical usefulness of measuring the time difference between onset of mitral inflow and onset of early diastolic mitral annulus velocity (T(E'-E)) for the evaluation of left ventricular (LV) diastolic function.

BACKGROUND

In recent studies, T(E'-E) correlated well with the time constant of LV pressure decay (tau), and the ratio of IVRT/T(E'-E), where IVRT is isovolumic relaxation time, was useful in the prediction of elevated LV filling pressure.

METHODS

Simultaneous left heart catheterization and Doppler echocardiography were performed in 40 patients.

RESULTS

The T(E'-E) was evaluated in the same cardiac cycle and in the same hemodynamic status in 31 patients. Despite the wide range of tau (31 to 70 ms), there was no delay in the onset of mitral annulus velocity compared with the onset of mitral inflow (T(E'-E) = 0) in 27 patients and, therefore, T(E'-E) did not correlate with tau. Only three patients showed prolongation in T(E'-E), and all three showed tau >or=50 ms and pre-A-wave pressure >or=18 mm Hg. In one patient, mitral annulus velocity began earlier than the onset of mitral inflow. Because T(E'-E) was 0 in the majority of patients, the LV filling pressure could not be predicted by the previously suggested index of IVRT/T(E'-E.)

CONCLUSIONS

In contrast to previous studies, T(E'-E) did not correlate with tau, and IVRT/ T(E'-E) could not be applied in the prediction of filling pressure, because of the limitation of a zero denominator. However, prolongation of T(E'-E) might suggest an elevated filling pressure in the setting of prolonged tau.

Cardiac structural and functional responses to salt loading in SHR

Increased dietary salt intake induces cardiac fibrosis in the spontaneously hypertensive rat (SHR), yet little information details its effects on left ventricular (LV) function. Additionally, young normotensive rats are more sensitive to the trophic effect of dietary sodium than older rats. Thus cardiac responses to salt loading were evaluated at two ages in the SHR; LV collagen content was also examined. SHR (8 or 20 wk of age) were given an 8% salt diet; their age-matched controls received standard chow. Echocardiographic indexes, arterial pressure, and LV hydroxyproline concentration were measured at 16 and 52 wk in the younger and older SHR groups, respectively. In most SHR, salt excess increased arterial pressure, LV mass, and hydroxyproline concentration and impaired LV relaxation manifested by prolonged isovolumic relaxation time, decreased early and atrial filling velocity ratio (V(E)/V(A)), and slower propagation velocity of E wave (V(P)). LV systolic function remained normal. However, one-quarter of the young salt-loaded SHR developed cardiac failure with systolic and diastolic dysfunction associated with greater LV mass and ventricular fibrosis. They also had lower arterial pressure, decreased fractional shortening, and a restrictive pattern of mitral flow. Moreover, the shorter deceleration time of the E wave and increased V(E)/V(P), an index of LV filling pressure, indicated increased LV stiffness in these rats. These findings demonstrated that sodium sensitivity in SHR is manifested not only by further pressure elevation but also by significant LV functional impairment that most likely is related to enhanced ventricular fibrosis. Moreover, the SHR are more susceptible to cardiac damage when high dietary salt is introduced earlier in life.

Long-term left ventricular echocardiographic follow-up of SHR and WKY rats: effects of hypertension and age

Long-term follow-up of left ventricular (LV) function using echocardiography has not been reported and, in this study, was carried out in normotensive (WKY) rats and spontaneously hypertensive rats (SHR). In 10 WKY rats and SHR, LV diastolic and systolic diameter (LVEDD and LVSD), shortening fraction (SF), and weight (LVW) were determined at 8, 15, 20, 35, and 80 wk of age. The ratio of early to late mitral flow and mitral annulus velocity (VE/VA and Em/Am), isovolumic relaxation time (IVRT), deceleration time of the E wave (DTE), Tei index, and mitral flow propagation velocity (Vp) were measured. No difference in LVEDD was found between SHR and WKY rats; however, LVEDD was increased at 80 wk in both strains. SF decreased slightly in old WKY rats. LVW progressively increased from 20 to 80 wk in both strains and was greater in SHR. VE/VA and Em/Am decreased at 80 wk in WKY rats. LV relaxation (IVRT, Tei index, and Vp) was progressively impaired in SHR compared with WKY rats. LV compliance (DTE) was altered in old SHR. Echocardiography permitted a long follow-up of LV function in SHR and WKY rats. Ventricular relaxation was impaired early in the life of SHR and progressed with aging. Furthermore, LV compliance was altered, but systolic function remained unchanged, in old SHR. In contrast, relaxation and SF were only slightly altered in old WKY rats, suggesting that pressure-related changes in LV function were the dominant features in the SHR.

Detection of a pseudonormal mitral inflow pattern: an echocardiographic and tissue Doppler study

OBJECTIVE

The aim of this study was to assess the ability of several echocardiographic and tissue Doppler imaging (TDI) derived parameters to improve the noninvasive diagnosis of a pseudonormal mitral inflow pattern.

METHODS

Ninety-eight consecutive patients with age-related normal transmitral Doppler profile underwent echocardiography including TDI and measurement of left ventricular end-diastolic pressure (LVEDP) using fluid-filled catheters. Peak transmitral velocities were determined at rest (E, A) and during the strain phase of a Valsalva maneuver. The difference in duration between the pulmonary venous retrograde velocity and the transmitral A-velocity (PVR-A) was calculated from pulsed Doppler recordings. Propagation velocity of the early mitral inflow (VP) was determined by color M-mode. Early diastolic peak mitral annulus velocities (E') and the early diastolic transmyocardial velocity gradient of the posterior basal wall (MVG) were obtained by TDI.

RESULTS

Fifty-two patients presented with normal diastolic function (group I: LVEDP9.5 +/- 3 mm Hg, E/A1.1 +/- 0.19), while pseudonormalization, defined as LVEDP 15 mm Hg and E/A > 0.9, was found in 46 patients (group II: LVEDP23 +/- 7 mm Hg, E/A1.43 +/- 0.83). The coefficient of linear correlation (r) and the area under ROC - curve (AUC) to predict LVEDP values 15 mm Hg were maximal for the index PVR-A (AUC = 0.92, r = 0.77), followed byE/E' (AUC = 0.80, r = 0.46), MVG (AUC = 0.65, r = 0.33) and E/VP (AUC = 0.69, r = 0.30), P < 0.01, whereas the decrease in E/A ratio during Valsalva maneuver failed to reach significance. Similar results were observed when echocardiographic parameters were used to estimate the left ventricular diastolic pressure before atrial contraction.

CONCLUSIONS

PVR-A enabled the most accurate estimation of LVEDP. TDI-derived indices E/E' and MVG are also reliable alternatives superior to the classical Valsalva maneuver to detect a pseudonormal transmitral Doppler profile.

Diagnosing diastolic heart failure

BACKGROUND

increasing evidence supports the existence of left ventricular diastolic dysfunction as an important cause of congestive heart failure, present in up to 40% of heart failure patients.

AIM

to review the pathophysiology of LV diastolic dysfunction and diastolic heart failure and the currently available methods to diagnose these disorders.

RESULTS

for diagnosing LV diastolic dysfunction, invasive hemodynamic measurements are the gold standard. Additional exercise testing with assessment of LV volumes and pressures may be of help in detecting exercise-induced elevation of filling pressures because of diastolic dysfunction. However, echocardiography is obtained more easily, and will remain the most often used method for diagnosing diastolic heart failure in the coming years. MRI may provide noninvasive determination of LV three-dimensional motion during diastole, but data on correlation of MRI data with clinical findings are scant, and possibilities for widespread application are limited at this moment.

CONCLUSIONS

in the forthcoming years, optimal diagnostic and therapeutic strategies for patients with primary diastolic heart failure have to be developed. Therefore, future heart failure trials should incorporate patients with diastolic heart failure, describing precise details of LV systolic and diastolic function in their study populations.

Echocardiographic assessment of diastolic function

Abnormal diastolic function is increasingly appreciated as a major contributor to cardiac morbidity and mortality. Accurate noninvasive assessment of the presence and severity of diastolic impairment is crucial to the broad application and understanding of this common condition. Echocardiographic parameters have become the backbone of this noninvasive assessment. Active investigation into both old and new Doppler variables will provide the framework that can lead to a more uniform assessment and reporting that will be essential as we prepare to confront clinically the next frontier in cardiac pathophysiology. This review discusses the clinical impact of recent echocardiographic contributions to the field of diastology.

Monophasic transmitral flow pattern with less increase in heart rate indicates left ventricular dysfunction

When heart rate (HR) increases, mitral flow can become monophasic. Prolonged isovolumic contraction and relaxation time (ICT and IRT), directly related to left ventricular (LV) function, can potentially influence the HR with monophasic mitral flow. The present study investigated the relation between HR that causes monophasic flow and LV function. During diagnostic catheterization, HR was increased using right atrial pacing by 2 beats/min every 2 min in a stepwise manner until the development of monophasic mitral flow in 17 patients with normal sinus rhythm. ICT, IRT, end-diastolic and end-systolic LV volumes, LV ejection fraction, LV peak + and -dP/dt, peak (+dP/dt)/P, and the relaxation time constant (tau) were measured by Doppler echocardiography or catheterization when monophasic mitral flow developed. The monophasic HR varied from 74 to 106 beats/min. By univariate analysis, ICT (p<0.01, r2=0.73), LV peak +dP/dt (p<0.05, r2=0.37), peak (+dP/dt)/P (p<0.01, r2=0.71), peak -dP/dt (p<0.05, r2=0.25), and tau (p<0.05, r2=0.33) had a significant correlation with monophasic HR. By multivariate analysis, prolonged ICT and reduced LV peak -dP/dt independently contributed to monophasic mitral flow with less increase in HR. Monophasic mitral flow with less increase in HR indicates impaired LV systolic and diastolic function during isovolumic contraction and relaxation.

Mitral annulus velocity in the estimation of left ventricular filling pressure: prospective study in 200 patients

The ratio of early mitral inflow to early mitral annular velocity (E/E') was suggested as a useful index in the estimation of left ventricular filling pressure. This study was performed to validate the clinical usefulness of E/E' ratio in a large number of patients. Simultaneous left ventricular pressure measurements and Doppler examinations were performed in 200 consecutive patients at the cardiac catheterization laboratory. The E/E' ratio correlated well with pre-A-wave pressure (r = 0.74, P <.001), and the correlation was not dependent on the left ventricular systolic function (ejection fraction [EF] > or = 50%: r = 0.74, P <.001 versus EF <50%: r = 0.70, P <.001). The E/E' ratio of > or = 9 best discriminated elevated (<12 mm Hg) from normal left ventricular pre-A pressure with a sensitivity of 81% and a specificity of 80%. Our study results also showed that quantitative estimation of left ventricular pre-A pressure could be suggested by the simplified equation of pre-A pressure = E/E' + 4 with reasonable accuracy.

Left ventricular wall motion velocities in healthy children measured by pulsed wave Doppler tissue echocardiography: normal values and relation to age and heart rate

Left ventricular wall motion velocities were measured by pulsed wave Doppler tissue (PWDT) echocardiography in 131 healthy children (mean age 7.5 +/- 5.5 years) at the interventricular septum and the posterior wall in the left ventricular short-axis view, and at the interventricular septum and the lateral wall in the 4-chamber view. The systolic wave (Sw) consisted of 2 components, and the difference between the 2 components was greater in the lateral wall than in the other walls. The peak early diastolic wave (Ew) velocity was also highest in the lateral wall. Most variables during systole correlated with age. The ratio of peak atrial systolic wave (Aw) velocity to peak Ew velocity (Aw/Ew) correlated with heart rate. The Aw/Ew in each wall correlated with the ratio of late (A) to early (E) peak mitral flow, although regression slopes differed among different wall segments. In younger children with increased heart rates, the Aw/Ew ratio increased because the Ew velocity decreased, although the A/E ratio increased because of an increased A velocity. Normal values for the PWDT variables change with heart rate and age in the pediatric population. The data reported in this study can be used as normal values for left ventricular function for PWDT echocardiography.

Estimation of mean right atrial pressure using tissue Doppler imaging

Sixty-two patients underwent simultaneous right atrial pressure measurement and Doppler echo including tissue Doppler to evaluate the utility of this technique in the estimation of right ventricular filling pressure. Mean right atrial pressure related weakly to the ratio of tricuspid peak early inflow velocity to annular early diastolic velocity (r = 0.75, p <0.0001), with a mean difference between Doppler and catheter pressures of 0.3 +/- 3.7 mm Hg.

Serial evaluation for myocardial performance in fetuses and neonates using a new Doppler index

BACKGROUND

Fetal echocardiography has been used for non-invasive evaluation of human fetal cardiac anatomy, function and hemodynamics. The Tei index, a new Doppler index known to be independent of both ventricular geometry and heart rate, has recently been applied to the evaluation of myocardial performance.

METHODS

In the present study, the Tei index was prospectively and longitudinally determined in 50 normal fetuses, 35 fetuses with intrauterine growth retardation (IUGR), 30 fetuses of diabetic mothers (DM) and 20 normal infants. The Tei index of both left and right ventricles was calculated from a Doppler ventricular inflow and outflow trace using the following formula: Tei index = (ICT + IRT)/ET, where ICT is isovolumetric contraction time; IRT, isovolumetric relaxation time; and ET, ejection time).

RESULTS

The Tei index of the left ventricle decreased linearly with advancing gestational age during 18-33 weeks and decreased acceleratively with increasing gestational age after 34 weeks. The index of the right ventricle decreased slightly and linearly with advancing gestational age during 18-41 weeks. In neonates, the Tci index of the left and right ventricle increased immediately and transitorily after birth and decreased and stabilized after 24 h of life. From 18 to 26 weeks of gestation, the Tei indices in fetuses with IUGR and of DM were not significantly different from controls. However, from 27 to 40 weeks of gestation, the Tei indices in both fetuses with IUGR and of DM were significantly greater than controls.

CONCLUSIONS

This gradual decrease in the Tei index during gestation may represent the maturational or developmental alternation of myocardial performance in utero. Fetuses with IUGR and of DM may have abnormal myocardial performance in later gestation.