Mitral flow velocity curves as a function of different loading conditions: evaluation by intraoperative transesophageal Doppler echocardiography

Antenatal dexamethasone treatment transiently alters diastolic function in the mouse fetal heart

Endogenous glucocorticoid action is important in the structural and functional maturation of the fetal heart. In fetal mice, although glucocorticoid concentrations are extremely low before E14.5, glucocorticoid receptor (GR) is expressed in the heart from E10.5. To investigate whether activation of cardiac GR prior to E14.5 induces precocious fetal heart maturation, we administered dexamethasone in the drinking water of pregnant dams from E12.5 to E15.5. To test the direct effects of glucocorticoids upon the cardiovascular system we used SMGRKO mice, with Sm22-Cre-mediated disruption of GR in cardiomyocytes and vascular smooth muscle. Contrary to expectations, echocardiography showed no advancement of functional maturation of the fetal heart. Moreover, litter size was decreased 2 days following cessation of antenatal glucocorticoid exposure, irrespective of fetal genotype. The myocardial performance index and E/A wave ratio, markers of fetal heart maturation, were not significantly affected by dexamethasone treatment in either genotype. Dexamethasone treatment transiently decreased the myocardial deceleration index (MDI; a marker of diastolic function), in control fetuses at E15.5, with recovery by E17.5, 2 days after cessation of treatment. MDI was lower in SMGRKO than in control fetuses and was unaffected by dexamethasone. The transient decrease in MDI was associated with repression of cardiac GR in control fetuses following dexamethasone treatment. Measurement of glucocorticoid levels in fetal tissue and hypothalamic corticotropin-releasing hormone (Crh) mRNA levels suggest complex and differential effects of dexamethasone treatment upon the hypothalamic-pituitary-adrenal axis between genotypes. These data suggest potentially detrimental and direct effects of antenatal glucocorticoid treatment upon fetal heart function.

Diastolic Function

Information about left ventricular function was traditionally provided primarily with measures of systolic function. Including the assessment of diastolic function has become an integral part of the evaluation of left ventricular function. Echocardiographic parameters of structure and Doppler provide information on each portion of the diastolic phases. These diastolic phases indicate change as impairment in diastolic function becomes more severe. This review of diastolic function provides the background as well as the techniques for clinical assessment of diastolic function in adult transthoracic echocardiography.

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.

Echocardiographic assessments of left atrial strain and volume in healthy patients and patients with mitral valvular heart disease by tissue Doppler imaging and 3-dimensional echocardiography

Background and Objectives

The purpose of the current study was to assess left atrial (LA) physiology in relation to associations between LA volume change and regional tissue velocities and strains, and to extend this information to patients with mitral stenosis (MS) or mitral regurgitation (MR).

Subjects and Methods

Twenty-two healthy persons, 22 patients with moderate-to-severe MS, and 22 patients with moderate-to-severe MR were studied. Tissue velocities, strains, and time-volume curves of the LA were acquired using tissue Doppler imaging and 3-dimensional echocardiography.

Results

In healthy controls, the maximal LA volume was negatively correlated with the posterior wall longitudinal systolic strain (r=-0.45, p=0.03). The time-to-maximal LA volume was positively correlated with the time-to-posterior wall longitudinal peak strain (r=0.46, p=0.03) and the time-to-circumferential peak strain (r=0.59, p=0.004). The LA active emptying fraction (LAactEF) was positively correlated with the posterior wall longitudinal peak systolic and late diastolic tissue velocities. In patients with MS, the maximal LA volume was negatively correlated with the posterior wall radial peak systolic velocity and the longitudinal late diastolic velocity. In patients with MS, the LAactEF had an additional positive correlation with the anterior wall longitudinal and circumferential systolic velocities, whereas the patients with MR had an additional positive correlation between the LAactEF and the lateral wall longitudinal peak strain as compared with the healthy cantrols.

Conclusion

LA longitudinal and circumferential deformations are more related than radial deformation to determining LA volume and function. The LA of patients with MS revealed a greater pathologic physiology than those of patients with MR.

Determinants of enhanced left atrial active emptying with aging: left atrial preload, contractility or both?

OBJECTIVE

Senile persons have reduced left ventricular (LV) relaxation and increased late diastolic filling. However, the determinant factor of the enhanced active emptying of the left atrium has not been well established.

METHODS

Subjects were 62 healthy individuals with a mean age of 58+/-19 (21-85) years. The biplane modified Simpson's rule was applied to measure left atrial (LA) volume at pre-atrial contraction (LAVpre) as an index of LA preload and LA volume change during atrial contraction (LASV) as an index of active LA emptying. These values were divided by the body surface area and represented as LAVpreI and LASVI, respectively. Postero-basal (dorsal cranial) left atrial wall velocity (LAWV) during atrial contraction as an index of LA contractility was measured in the apical three-chamber view by two-dimensional tissue Doppler echocardiography.

RESULTS

Age significantly correlated with mitral flow velocity (TMA), velocity-time integral during atrial contraction (TMAVTI) and LASVI (r= 0.63, p<0.001 and r=0.71, p<0.001, r=0.21, p=0.049, respectively). LAVpreI was significantly correlated with age (r=0.44, p<0.001), LASVI (r=0.71, p<0.001), TMA (r=0.31, p=0.008) and TMAVTI (r=0.40, p<0.001). LAWV remained unchanged with aging and had no correlation with TMA, TMAVTI or LASVI.

CONCLUSION

The enlargement of the LA in senile persons may be a major determinant of enhanced active LA emptying and the increased LA contractility may be less contributory.

Pulmonary hypertension in sickle-cell disease: comorbidities and echocardiographic findings

BACKGROUND

Our aim is to determine comorbidities associated with pulmonary hypertension (PHT) in clinically stable sickle-cell disease (SCD) patients and to evaluate left ventricular (LV) and right ventricular (RV) function in those patients.

METHODS

Echocardiography was performed in 87 SCD patients that were divided into group I (without PHT) and group II (with PHT). Both groups were compared with healthy controls.

RESULTS

A history of retinopathy and leg ulcer was more frequent in group II than group I (p < 0.01). Haemoglobin levels were lower (p < 0.05), whereas blood urea nitrogen, lactate dehydrogenase and total bilirubin levels were higher in group II (p < 0.01). Although group II patients had larger LV end-diastolic, LV end-systolic and RV diastolic diameters compared with group I patients and controls (p < 0.05), LV ejection fraction was similar in the three groups. The mitral peak early diastolic inflow velocity to peak late diastolic inflow velocity (E/A) ratio was similar in group I, group II and the control group. The tricuspid E/A ratio was lower in group II than group I and controls (p < 0.05).

CONCLUSION

End organ damage occurs more often and haemolysis is severer in SCD patients with PHT than SCD patients without PHT. Although LV systolic and diastolic function is well preserved, RV diastolic function is disturbed in those patients with PHT.

Tissue Doppler velocity is not totally preload-independent: a study in a uremic population after hemodialysis

OBJECTIVES

The aim of this study was to investigate the changes of regional tissue Doppler velocity after volume removal following regular hemodialysis (HD) in uremic patients. Is tissue Doppler velocity really preload-independent?

BACKGROUND

Diastolic dysfunction was divided into four stages: normal pattern, abnormal relaxation pattern, pseudonormalization pattern, and restrictive pattern. Pulse wave Doppler and color Doppler echocardiography were important diagnostic tools for these forms of diastolic dysfunction. However, they were preload-dependent and sometimes there was confusion between the normal pattern and the pseudonormalization pattern. Tissue Doppler echocardiography was promising for problems in diastolic dysfunction and appeared to be preload-independent. However, there are still some disputes over this point.

METHODS

Ninety-three uremic patients receiving regular HD were included in the study. There were 45 males and 48 females aged 59 +/- 14 years. The mean volume removed after HD was 2.3 +/- 0.9 kg. The mean heart rates before and after HD were 77 +/- 11 and 76 +/- 12 beats per minute, respectively (p = 0.73). All patients received complete transthoracic echocardiography examinations before and after HD. The studies included cardiac chamber size, left ventricular systolic performance, pulse wave Doppler echocardiographic data of mitral inflow and the right upper pulmonary vein including peak velocity of early diastolic E wave, E wave time velocity integral (TVI-E), peak velocity of late diastolic A wave, A wave TVI, systolic phase of pulmonary vein (S wave TVI), early diastolic phase of pulmonary vein (D wave TVI) and atrial contraction phase of pulmonary vein (Ar wave TVI). Pulsed tissue Doppler echocardiography (TDE) was performed and a 4-mm sample volume was placed at the 6 corners of the mitral annulus including septal, lateral, anterior, inferior, anteroseptal and posterior corners. Five to ten cardiac cycles were recorded and the data were averaged. Measurements performed included peak velocity of systolic phase (Sa), early diastolic phase (Ea), late diastolic phase (Aa), Ea/Aa ratio and time from the beginning of electrocardiogram Q wave to the beginning of Sa (Q-Sa time). The same measurements were repeated after HD.

RESULTS

After HD, left atrium diameter and left ventricular internal dimensions at end diastole became smaller. There were significant reductions for mitral peak E wave velocity, TVI-E, peak A wave velocity and E/A ratio. As for the pulmonary vein, systolic phase of pulmonary vein and early diastolic phase of pulmonary vein decreased significantly. Peak Ar wave did not change significantly. For TDE, Sa and Aa did not change but Ea did decrease.

CONCLUSION

After HD, there is a significant reduction of intravascular effective volume. No significant change is found for myocardial peak systolic velocity and peak late diastolic velocity. However, there is a significant reduction of myocardial early diastolic phase peak velocity. This suggests that TDE is not completely preload-independent; at least, it is phase-dependent within each cardiac cycle.

Clinical Utility of Tissue Doppler Imaging in Prediction of Atrial Fibrillation After Coronary Artery Bypass Grafting

BACKGROUND

Atrial systolic dysfunction in patients with coronary artery disease might influence the development of atrial fibrillation after coronary artery bypass grafting (CABG). Tissue Doppler imaging of the mitral annulus during atrial systole has proved to quantify, accurately, left atrial contractile function. Therefore, the aim of the present study was to investigate the correlation between preoperative left atrial dysfunction assessed by tissue Doppler and postoperative atrial fibrillation after CABG.

METHODS

We studied a total of 96 patients (mean age 67 +/- 6 years; range, 55 to 81) undergoing CABG who were preoperatively in sinus rhythm. All patients underwent a preoperative transthoracic echocardiography with tissue Doppler evaluation. Until the day of discharge, all patients were monitored with continuous electrocardiographic telemetry.

RESULTS

There were no hospital deaths. Postoperative atrial fibrillation was recorded in 24 of 96 patients (25%). Patients with postoperative atrial fibrillation were significantly older (70 +/- 6 vs 65 +/- 8 years; p = 0.006), had a preoperative larger left atrium diameter (38 +/- 5 vs 36 +/- 4 mm; p = 0.045), a larger left atrium area (13.2 +/- 3.4 vs 11.5 +/- 2.3 cm2; p = 0.007), and a lower peak atrial systolic mitral annular tissue Doppler velocity (10 +/- 3 vs 13 +/- 5 cm/second; p = 0.01). Stepwise logistic regression analysis showed that age 70 years or greater (p = 0.02; odds ratio [OR] 2.0), preoperative medication with beta-blockers (p = 0.04; OR 0.7), left atrium area 13 cm2 or greater (p = 0.02; OR 2.5), and peak atrial systolic mitral annular tissue Doppler velocity 9 cm/second or less (p = 0.03; OR 1.8) were independently related with the incidence of postoperative atrial fibrillation.

CONCLUSIONS

Tissue Doppler is useful for assessing preoperative atrial dysfunction and predicting atrial fibrillation after CABG. Further studies are needed to confirm this finding.

Reduction of N terminal-pro-brain (B-type) natriuretic peptide levels with exercise-based cardiac rehabilitation in patients with left ventricular dysfunction after myocardial infarction

INTRODUCTION

N-terminal-pro-brain (B-type) natriuretic peptide (NT-pro-BNP) is a peptide hormone released from ventricles in response to myocyte stretch. The aim of the study was to investigate the influence of exercise training on plasma NT-pro-BNP to verify if this parameter could be used as a biological marker of left ventricular remodelling in myocardial infarction patients undergoing an exercise training programme.

METHODS

Forty-four patients after myocardial infarction were enrolled into a cardiac rehabilitation programme, and were randomized in two groups of 22 patients each. Group A patients followed a 3-month exercise training programme, while group B patients received only routine recommendations. All patients underwent NT-pro-BNP assay, and cardiopulmonary exercise test before hospital discharge and after 3 months.

RESULTS

In Group A, exercise training reduced NT-pro-BNP levels (from 1498+/-438 to 470+/-375 pg/ml, P=0.0026), increased maximal (VO2peak+4.3+/-2.9 ml/kg per min, P<0.001; Powermax+38+/-7, P<0.001) exercise parameters and work efficiency (Powermax/VO2peak+1.3+/-0.4 Power/ml per kg per min, P<0.001); there was also an inverse correlation between changes in NT-pro-BNP levels and in VO2peak (r=-0.72, P<0.001), E-wave (r=-0.51, P<0.001) and E/A ratio (r=0.59, P<0.001). In group B, at 3 months, no changes were observed in NT-pro-BNP levels, exercise and echocardiographic parameters.

CONCLUSION

Three months exercise training in patients with moderate left ventricular systolic dysfunction after myocardial infarction induced a reduction in NT-pro-BNP levels, an improvement of exercise capacity and early left ventricular diastolic filling, without negative left ventricular remodelling. Whether the reduction of NT-pro-BNP levels could be useful as a surrogate marker of favourable left ventricular remodelling at a later follow-up remains to be further explored.

Color M-mode flow propagation velocity: is it really preload independent?

OBJECTIVE

This study investigates the change in flow propagation velocity (FPV) in uremic patients who undergo regular hemodialysis (H/D).

MATERIALS AND METHODS

We studied 93 uremic patients (44 men and 49 women; 59 +/- 14-years-old) receiving regular hemodialysis. Patients were separated by baseline left ventricular ejection fraction (LVEF): 71 patients with LVEF > 50% (group 1), 13 patients with LVEF 35-50% (group 2), 7 patients with LVEF < 35% (group 3). All patients were in sinus rhythm before H/D. They received complete transthoracic echocardiographic examinations. Flow propagation velocity was measured by color M-mode echocardiography in apical four chambers view. All these parameters were obtained before and after H/D. Paired data were compared. According to different H/D amounts, we viewed the FPV response after H/D in variant baseline LVEF groups.

RESULT

The baseline FPV became lower in patients with low LVEF. After H/D, obvious decrement of FPV occurred in group 1, but there were no obvious changes in groups 2 and 3. In fact, a slight increment of FPV was found in group 3. In patients with baseline LVEF > 50%, FPV after H/D was almost always lower, regardless of H/D amount. But there was different response in patients with baseline LVEF < 50%.

CONCLUSION

Flow propagation velocity is preload independent in patients with LVEF < 50%, but it is preload-dependent in patients with LVEF > 50%.

Preload and Flow Propagation Velocity: Insight into Patients with Uremia and Different Left Ventricular Systolic Function

OBJECTIVES

The aim of this study was to investigate the changes of flow propagation velocity (FPV) after regular hemodialysis (H/D) in patient who were uremic with different baseline left ventricular (LV) functions.

METHODS

In all, 24 patients with uremia and abnormal LV systolic function were enrolled in this study and 30 patients with uremia and normal LV systolic performance served as the control group. All patients had in sinus rhythm and underwent a comprehensive transthoracic echocardiographic examination and mitral FPV by color M-mode echocardiography before and after H/D.

RESULTS

The decline in FPV before H/D was proportional to the decline in the baseline LV function, whereas FPV after H/D varied according to the LV ejection fraction. An obvious decrement of FPV for patients with normal LV systolic function was noted, but no obvious difference was seen for patients with abnormal LV systolic function.

CONCLUSION

FPV was strongly preload dependent for patients with normal LV systolic function. It was not significantly influenced by preload for patients with abnormal LV systolic function. FPV is a relatively good diastolic parameter for investigating patients with LV systolic dysfunction.

Doppler Tissue Imaging and Color M-Mode Flow Propagation Velocity: Are They Really Preload Independent?

OBJECTIVE

This study investigated the change in new diastolic indexes in patients with uremia who undergo regular hemodialysis (H/D).

METHODS

We studied 81 patients with uremia (41 men and 40 women) receiving regular H/D. All patients were in sinus rhythm before H/D. They had normal left ventricular systolic performance without regional wall-motion abnormality. Three patients were excluded because of atrial fibrillation after H/D. Patients were separated by the amount of body fluid removed during H/D procedure: 30 patients with H/D amount less than 2 kg (group 1), 33 patients with H/D amount between 2 and 3 kg (group 2), and 18 patients with H/D amount larger than 3 kg (group 3). They received complete transthoracic echocardiographic examinations. Flow propagation velocity (FPV) was measured by color M-mode echocardiography in apical 4-chamber view. Mitral annulus Doppler tissue velocities (peak systolic [Sa], early diastolic [Ea], and late diastolic [Aa]) were measured from septal, lateral, inferior, and posterior walls. All these parameters were obtained immediately before and after H/D. Paired data were compared.

RESULTS

In patients with removed fluid amount less than 2 kg (group 1), the change of all diastolic parameters showed insignificant change except FPV (peak mitral E, P = .14; peak mitral A, P = .916; FPV, P = .009; septal Sa, P = .173; septal Ea, P = .295; septal Aa, P = .649). In patients with H/D amount between 2 and 3 kg, the change of all diastolic parameters showed statistically significant difference except Sa (peak mitral E, P = .001; peak mitral A, P = .001; FPV, P = .001; Sa, P = .589; Ea, P = .001; Aa, P = .015). In patients with H/D amount larger than 3 kg, Sa still showed insignificant change. Ea, Aa, and FPV showed significant difference after H/D (peak mitral E, P = .001; peak mitral A, P = .035; FPV, P = .008; septal Sa, P = .777; septal Ea, P = .014; septal Aa, P = .048).

CONCLUSION

In patients with normal left ventricular systolic function, FPV was preload dependent. Diastolic phase mitral annulus Doppler tissue velocities (Ea and Aa) behaved differently according to the amount removed during H/D. They were preload independent when the amount removed during H/D was less than 2 kg. When the amount removed during H/D was larger than 2 kg, diastolic phase mitral annulus Doppler tissue velocities changed significantly. That is to say, diastolic phase mitral annulus Doppler tissue velocities were not totally preload independent. For systolic phase mitral annulus Doppler tissue velocity index (Sa), it was preload independent.

Noninvasive differentiation of pseudonormal/restrictive from normal mitral flow by Tei index: a simultaneous echocardiography-catheterization study in patients with acute anteroseptal myocardial infarction

BACKGROUND

Differentiation of pseudonormal/restrictive from normal mitral flow is still clinically problematic. Pseudonormal/restrictive flow is usually associated with left ventricular dysfunction, which can be detected by Doppler Tei index, combining systolic and diastolic function. Therefore, the purpose of this study was to test the feasibility of the Tei index to differentiate pseudonormal/restrictive from normal mitral flow.

METHODS

In 26 patients with anteroseptal acute myocardial infarction and early diastolic mitral flow velocity (E) to late diastolic mitral flow velocity (A) ratio (E/A) > or = 1, left ventricular volumes; E and A; deceleration time of E; and the Tei index, defined as the sum of the isovolumic contraction and relaxation time divided by ejection time, were evaluated by Doppler echocardiography, and pulmonary capillary wedge pressure was measured by catheterization. Pseudonormal/restrictive mitral flow was defined as E/A > or = 1 associated with pulmonary capillary wedge pressure > 12 mm Hg.

RESULTS

There were 19 and 7 patients with pseudonormal/restrictive and normal mitral flow, respectively. Among the indices of left ventricular function, the Tei index achieved the best correlation with pulmonary capillary wedge pressure (r(2) = 0.66, P <.0001). By setting the Tei index > or = 0.55 as the criteria for pseudonormal/restrictive mitral flow, this diagnosis had the sensitivity, specificity, and accuracy of 84%, 100%, and 88%, respectively.

CONCLUSION

The Tei index allows noninvasive differentiation of pseudonormal/restrictive from normal mitral flow.

Left ventricular remodelling, and systolic and diastolic function in young adults with beta thalassaemia major: a Doppler echocardiographic assessment and correlation with haematological data

OBJECTIVE

To evaluate left ventricular morphology and function in a large population of patients with beta thalassaemia.

DESIGN

Echo Doppler assessment of left ventricular function and correlation of cardiovascular data with haematological data.

SETTING

Thalassaemia unit in a tertiary referral centre.

PATIENTS

197 young adults with beta thalassaemia, following an adequate transfusional and chelation treatment regimen, without clinical signs of cardiopulmonary involvement. The control group consisted of 213 healthy subjects.

RESULTS

Left ventricular volumes, mass index, and mass/volume ratio were increased. Diastolic and systolic shapes were different, the left ventricle maintaining an ellipsoidal shape. The ejection fraction was reduced, and was < 50% in 33 patients. Stroke volume and cardiac index were increased, and systemic vascular resistance was decreased. Fractional shortening and mean velocity of circumferential shortening were decreased. Meridional end systolic and peak systolic stress were increased, as was circumferential end systolic stress. The contractile state was reduced while the functional preload index did not differ. Left ventricular diastolic function, evaluated from the mitral inflow, showed a slightly prolonged isovolumic relaxation time, increased flow velocity integrals, and an increased E/A ratio. Among the haematological data, only serum ferritin showed a weak negative correlation with left ventricular ejection fraction. The patients with the highest serum ferritin (> 2500 ng/ml) had the lowest ejection fraction.

CONCLUSIONS

Patients with beta thalassaemia on an adequate transfusion and chelation treatment regimen show abnormal left ventricular remodelling with increased volumes, mass, and mass/volume ratio. Systolic chamber function and contractile state are reduced, with a slightly increased afterload. These findings seem mainly to be related to the increased cardiac output caused by chronic anaemia. Left ventricular performance is better preserved when chelation treatment is adjusted to maintain the serum ferritin concentration at < 1000 ng/ml.

Does the myocardial performance index affect pulmonary artery pressure in patients with mitral stenosis? A tissue Doppler imaging study

BACKGROUND

The relation between systolic pulmonary artery pressure (PAP) and mitral stenosis (MS) has been poorly understood. Although the mitral valve area (MVA) is an important factor affecting the PAP, there is a wide spectrum of the PAP in patients with MS despite a similar MVA. So, we analyzed whether the left and right ventricular myocardial performance index (MPI) correlated with the PAP.

METHODS

Two-dimensional Doppler echocardiography was performed in 46 patients with MS. The left atrial diameter, mean mitral gradient, and MVA were measured. The PAP was derived from the tricuspid regurgitant jet velocity. The ejection time (ET), isovolumetric relaxation time (IRT), and contraction time (ICT) were measured on annulus of interventricular septum, lateral, inferior and anterior wall of left ventricle, and right ventricle free wall from apical two- and four-chamber views in patients with MS and 40 age-matched healthy patients by tissue Doppler imaging (TDI). Then the MPI was calculated as (IRT + ICT)/ET for both left and right ventricle. The correlation of PAP with MVA, mean mitral gradient, left atrial diameter, and left and right ventricular MPI was evaluated.

RESULTS

MVA and PAP were measured as 1.57 +/- 0.39 cm2 (0.8-2.5 cm2)and 42 +/- 16 mmHg, respectively. It was determined that the MPI increased in patients with MS(0.59 +/- 0.1 vs 0.48 +/- 0.07, P < 0.001). It was also demonstrated that the MVA, left atrial diameter, mean diastolic gradient, and left ventricular MPI were correlated with PAP(r =-0.39 [P = 0.007], r = 0.43 [P = 0.003], r = 0.58 [P < 0.001], and r = 0.65 [P < 0.001], respectively). In multivariate analysis, although the PAP correlated with mean diastolic gradient and MPI (r = 0.39 [P = 0.013], and r = 0.48 [P < 0.001]), it did not correlate with left atrial diameter and MVA. The PAP also correlated with right ventricular MPI(r = 0.63 [P < 0.001]).

CONCLUSION

This study demonstrates that the left ventricular MPI obtained by TDI is an important marker of PAP, and right ventricular MPI correlates with the PAP in patients with MS.

Noninvasive differentiation of normal from pseudonormal/restrictive mitral flow using TEI index combining systolic and diastolic function

Differentiation of normal from pseudonorma/restrictive mitral flow is not necessarily easy. Pseudonormal/restrictive flow is usually associated with left ventricular (LV) dysfunction, which can be detected using the TEI index, combining systolic and diastolic function. The purpose of this study was to test the feasibility of using the TEI index to differentiate pseudonormal/restrictive from normal mitral flow. In 33 patients with mitral flow E/A > or = 1 and LV mid-diastolic pressure measured by catheterization, the LV volumes, mitral E and A velocity, deceleration time of the E velocity, and the TEI index, defined as the sum of the isovolumic contraction and relaxation time divided by ejection time, were evaluated using Doppler echocardiography. Pseudonormal/restrictive mitral flow was defined as mitral flow E/A > or = 1 associated with LV mid-diastolic pressure > 12 mmHg. There were 22 and 11 patients with normal and pseudonorma/restrictive mitral flow, respectively. Among the indices of LV function, the TEI index achieved the best correlation with LV mid-diastolic pressures (r2 = 0.63, p < 0.0001). By setting the TEI index > or = 0.65 as the criteria for pseudonormal/restrictive mitral flow, this diagnosis had sensitivity, specificity, and accuracy of 82%, 96%, and 91%, respectively. TEI index allows noninvasive differentiation of pseudonormal /restrictive from normal mitral flow.

Deceleration time of early filling in patients with left ventricular systolic dysfunction: functional and prognostic independent value

BACKGROUND

Although diastolic function parameters have been mentioned as significant predictors of functional capacity and prognosis in patients with left ventricular (LV) systolic dysfunction, it has not been fully elucidated whether they keep an independent predictive value when multiple parameters from a wide variety of examinations are considered.

METHODS

We prospectively studied 60 patients with New York Heart Association (NYHA) class II-IV chronic heart failure symptoms and LV ejection fraction <0.4. At the time of entry into the study, demographic data and functional class were obtained, and usual Doppler echocardiographic, radionuclide ventriculographic, cardiopulmonary exercise testing and hemodynamic variables were determined. Deceleration time of early filling (DT) and NYHA functional class were the only independent predictors of functional capacity as assessed by means of peak oxygen uptake (peak VO2). Mean follow-up was 21 +/- 6 months, and event-free survival was defined as the absence of cardiac death, urgent cardiac transplantation, or hospital admission requiring inotropic or mechanical support.

RESULTS

Multivariate Cox analysis showed that DT (P =.008), peak VO2 (P =.01), and NYHA class (P =.02) were independent predictors of event-free survival at 1 year. Patients in the lowest tertile of DT (<130 ms) had a significantly lower event-free survival than patients in the intermediate (44% vs 80%, P =.03) and in the highest tertile (44% vs 83%, P =.02). Patients with both a DT <130 milliseconds and a peak VO2 <14 mL/kg/min had the highest rate of events at 1 year (83% vs 22% for the remaining patients, relative risk 3.75, P <.001).

CONCLUSIONS

In patients with LV systolic dysfunction, DT is a powerful independent predictor of functional capacity and prognosis among a wide variety of variables. A shortened DT (<130 ms) identifies a subgroup of patients with a worse outcome, especially when combined with a reduced peak VO2 (<14 mL/kg/min).

Left ventricular remodeling, systolic function, and diastolic function in young adults with beta-thalassemia intermedia: a Doppler echocardiography study

BACKGROUND

The aim of this study was to investigate the left ventricular (LV) remodeling and function in 24 asymptomatic young adults affected by beta-thalassemia intermedia (TI), in order to compare the obtained data with that of 80 patients affected by beta-thalassemia major (TM) and 65 healthy subjects.

METHODS

LV volumes and shapes, mass index, mass/volume ratio, systolic and diastolic function, stroke volume, and cardiac index were determined by two-dimensional and M-mode echocardiography.

RESULTS

In the TM and TI groups, LV volumes, diastolic and systolic shapes were significantly different from the control subjects, but the ejection fraction was slightly reduced only in the TM group. The TI group had larger LV volumes than did the TM group (mean [+/- SD] end-diastolic volume index, 99.4 +/- 21.9 vs 82.7 +/- 21.5 mL/m(2), respectively [p < 0.005]; mean end-systolic volume index, 42.8 +/- 12.2 vs 36.1 +/- 12.9 mL/m(2), respectively [p < 0.05]). Both groups showed an increase of the LV mass index, but the mass/volume ratio did not differ from the control subjects. The systolic volume index and the cardiac index were increased in both groups, but the increase was more pronounced in the TI group. Fractional shortening (FS) and the mean velocity of circumferential shortening (mVCFc) were decreased in the TM group (FS, 33.6 +/- 5.5% vs 36.9 +/- 4.1, respectively [p < 0.001]; mVCFc, 1.06 +/- 0.18 vs 1.17 +/- 0.12 circumference per second, respectively [p < 0.0001]). The LV contractile state was depressed only in the TM group, and the preload index was normal in both. LV filling showed an increase in the total flow velocity integral due to increases in the peak E wave (E) and peak A wave (A) velocities and integrals, with an increase of the E/A ratio in the TM group and a slight decrease in the TI group. The isovolumic relaxation time was prolonged in both groups. There was no major derangement in the pulmonary venous flow.

CONCLUSIONS

Asymptomatic young adults with TI show significant increases in LV volumes, LV mass, and cardiac index that are more pronounced than those in TM patients. LV systolic function is preserved in the TI group but is slightly depressed in the TM group due to the increase of afterload and to reduced contractility. The hemodynamic and hematologic factors involved in the etiopathogenesis of these findings are discussed, such as the treatment strategy.

Transesophageal echocardiographic (TEE) evaluation of ventricular function

Transesophageal echocardiography (TEE) provides excellent delineation of ventricular function in the ambulatory and critical settings. Major indications include the acutely ill patient with suboptimal images with other techniques and the intraoperative assessment of patients undergoing cardiac surgery and of cardiac patients undergoing noncardiac surgery. The methodology of quantification of ventricular function is quite accurate, though it has inherent limitations. Newer technologies, such as edge enhancement techniques, three-dimensional acquisition, and contrast agents, all have the potential to improve evaluation of ventricular function with TEE. Stress imaging with TEE is possible with dobutamine and with pacing techniques. This is sage and accurate, and it is indicated in patients, such as the morbidly obese, who are impossible to image by other methods.

The influence of heart rate on the Doppler-derived myocardial performance index

The Doppler-derived myocardial performance index (MPI), defined as the sum of isovolumetric contraction and relaxation durations divided by ejection time and reflecting both systolic and diastolic myocardial function, has been found to be related to morbidity and mortality in cardiac diseases. The MPI is easily obtained, reproducible, and has a narrow range in healthy subjects. The goal of this study was to study the influence of heart rate changes on the MPI. Thirty patients with sick sinus syndrome treated with a pacemaker with a right atrial lead were studied. The patients were paced at increasing rates from 50 to 100 bpm. The MPI increased on average 0.02 +/- 0.03 per 10-bpm increase in rate. The correlation between MPI and heart rate was weak (rho = 0.31, P <.01).

Echocardiographic determination of left atrial function and its application for assessment of mitral flow velocity pattern

We determined left atrial (LA) volume changes to evaluate LA function, and to correlate the Doppler-determined mitral flow velocity (MFV) pattern. Twenty-four patients with ischemic heart disease who showed 'normal' MFV pattern by pulsed Doppler echocardiography were studied. The patients were divided into 14 patients with left ventricular end diastolic pressure < 18 mmHg (true normals) and 10 patients with > or = 18 mmHg (pseudo normals). The changes in LA volume were determined by echocardiography from apical two- and four-chamber views with modified Simpson's method. The volume measurements were done at the time of mitral valve opening (Vmax), at onset of atrial systole (Va) and at mitral valve closure (Vmin). Then the passive LA emptying volume was calculated by subtracting Va from Vmax, and the active LA emptying volume by subtracting Vmin from Va. The LA ejection fraction was calculated by the formula: [(Va-Vmin)Va] x 100. There was no significant difference in LA ejection fraction in pseudo normal (39+/-6%) and in true normal (41+/-13%) patients. Although the passive LA emptying volume was 16+/-4 ml/beat in true normal and was 11+/-3 ml/beat in pseudo normal (NS), the active LA emptying volume was significantly greater in pseudo normals (22+/-4 m/beat) than in true normals (12+/-2 ml/beat, P<0.001). Thus, the ratio of passive and active LA emptying volume was markedly greater in true normals (1.28+/-0.35) than in pseudo normals (0.52+/-0.19, P<0.001), facilitating the differentiation of these two groups. These results indicate that two-dimensional echocardiographic measurement of LA volume can be valuable in assessing the LA function, providing an alternative method for differentiating pseudo normal from true normal MFV pattern in clinical settings, although several technological shortcomings should be resolved.

Effect of preload alternations on a new Doppler echocardiographic index of combined systolic and diastolic performance

The objective of the study was to assess the effect of preload alternations on a nongeometric Doppler index of combined systolic and diastolic myocardial performance (MPI). Doppler echocardiography was performed during Valsalva maneuver, passive leg lifting, and after sublingual administration of nitroglycerin in 50 healthy volunteers (group 1) and 25 patients (group 2) with previous myocardial infarction. MPI was significantly lower in group 1 (0.34 +/- 0.04) compared with group 2 (0.52 +/- 0.14), P <.0005. In group 1 MPI was significantly increased during preload manipulations (P =. 001). The largest change in MPI was induced by nitroglycerin (0.034 +/- 0.05). In group 2 no significant changes in MPI were found. In both groups peak E-wave velocity (P <.0005), E/A-ratio (P <.0005), and E-wave deceleration time (P <.0005) were found to change during preload alternations. In conclusion, we found in normal subjects and to a lesser extent in patients with previous myocardial infarction that MPI is influenced by preload.

Transesophageal echocardiographic area and Doppler flow velocity measurements: comparison with hemodynamic changes in coronary artery bypass surgery

OBJECTIVE

Changes in transesophageal echocardiography (TEE)-derived Doppler flow velocities through the mitral valve and pulmonary veins occur after cardiopulmonary bypass and are believed to reflect left ventricular (LV) diastolic functional impairment. The aim of this study was to determine the time-coincidence between these Doppler flow velocity parameters, LV two-dimensional (2D) short-axis area measurements, and hemodynamic parameters in patients after coronary artery bypass grafting.

DESIGN

Prospective clinical study.

SETTING

University hospital.

PARTICIPANTS

Twenty patients with normal ejection fraction undergoing elective cardiac surgery.

INTERVENTIONS

At multiple intervals during surgery and 6 hours postoperatively, mitral inflow velocity and pulmonary venous flow velocity were measured with pulsed Doppler TEE. LV short-axis area by echocardiography and cardiac output by thermodilution were simultaneously obtained.

MEASUREMENTS AND MAIN RESULTS

Time-coincidence was found in the immediate postbypass period between a decreased E/A ratio from 1.16 (95% confidence interval, 1.0 to 1.31) to 0.64 (95% confidence interval, 0.47 to 0.81, p < 0.01), a decreased E-wave deceleration time, and a significantly increased heart rate (HR) and cardiac index. End-diastolic area (EDA) and stroke volume index (SVI) decreased after sternal closure. HR, E-wave deceleration time, and SVI remained altered until 6 hours postoperatively. No change was found in pulmonary venous flow velocity parameters and systolic LV function.

CONCLUSION

In patients with normal systolic ventricular function and no inotropic support, Doppler flow velocity patterns alone did not sufficiently reflect hemodynamic changes, whereas 2D LV area, especially EDA measurements, provided useful information about hemodynamically significant LV filling impairment.

Transnasal transesophageal echocardiography: a modified application mode for cardiac examination in ventilated patients

In 42 endotracheally intubated patients, we examined the utility of a miniaturized monoplane probe for transnasal transesophageal echocardiography (TEE). Transnasal TEE was prospectively evaluated in 26 deeply and 16 mildly sedated patients receiving topical anesthesia with lidocaine jelly 2%. The patients with deep sedation were additionally examined with transoral monoplane and multiplane TEE. Transnasal esophageal insertion of the TEE probe was successfully performed in 90% of patients. Endotracheal malpositioning was corrected in two patients. Nasal bleeding required treatment in another patient. Topical anesthesia was adequate in 82% of mildly sedated patients. Left ventricular short- and four-chamber long-axis views of good quality were obtained with transnasal (transoral) monoplane TEE in 76% (81%) and 92% (96%) of patients (differences not significant). Compared with conventional multiplane TEE, transnasal monoplane TEE missed diagnoses in 19% of patients. The relative error (mean +/- SEM) of quantification with transnasal TEE was <9% +/- 2% for ventricular diameters and <7% +/- 2% for cross-sectional area measurements, with a bias of 0.5 +/- 3.8 cm2 and 0.1 +/- 2.4 cm2 (mean +/- 2 SD) for left ventricular end-diastolic and end-systolic short-axis areas. The relative error in measuring intracardiac flow velocities was >40%, but systolic to diastolic peak velocity ratios at the valvular site were determined with an error <4% +/- 3%. Transnasal monoplane TEE can be performed even in mildly sedated patients with an endotracheal tube without further need for analgesia or sedation. The technique is as useful as conventional transoral TEE to image standard tomographic planes for quantification, but it is less suited for comprehensive echocardiographic diagnosing.

IMPLICATIONS

Transnasal insertion of a miniaturized monoplane transesophageal echocardiography (TEE) probe was studied in endotracheally intubated patients. Nasal passage was well tolerated even by patients with only mild sedation. Imaging quality was similar to conventional transoral monoplane TEE with larger transducers, but technical restraints cause a deficit in complete cardiac diagnosing obtained with multiplane TEE.

Prognostic value of a Doppler index combining systolic and diastolic performance in idiopathic-dilated cardiomyopathy

This study sought to investigate, in patients with idiopathic-dilated cardiomyopathy, the clinical and prognostic value of a Doppler-derived index of myocardial function that combines systolic and diastolic time intervals of the left heart cycle. The Doppler index was measured in 75 patients (aged 61 +/- 13 years; 45 men and 30 women) in sinus rhythm and 75 age- and sex-matched controls. Ejection time was measured from the left ventricular outflow Doppler signal. The sum of isovolumic times was obtained by subtracting the ejection time from the interval between cessation and onset of mitral inflow measured from the mitral inflow velocity profile. The index was the sum of isovolumic times divided by ejection time. The values of the Doppler index in patients with idiopathic-dilated cardiomyopathy (0.85 +/- 0.32) were significantly higher than values in controls (0.37 +/- 0.08, p < 0.001). During follow-up of 5 years, 1 patient underwent cardiac transplantation and 36 patients died, 29 of cardiac, 5 of noncardiac, and 2 of unknown causes. Univariate analysis demonstrated that the Doppler index (chi-square = 18.3, p < 0.001), ejection fraction (chi-square = 15.2, p <0.001), symptom status (chi-square = 9.2, p = 0.002), and mitral deceleration time (chi-square = 5.2, p = 0.02) were significant predictors of outcome. However, multivariate stepwise analysis of these variables showed that the Doppler index (chi-square = 10.7, p = 0.001) and ejection fraction (chi-square = 6.7, p = 0.01) were the most significant independent predictors of outcome. The Doppler index reflects disease severity and has incremental prognostic value in dilated cardiomyopathy. Ease of use, nongeometric dependency, excellent separation of clinical groups, and a strong relation to outcome enhance its appeal.

Transesophageal echocardiographic evaluation during negative-pressure ventilation using the Hayek oscillator

OBJECTIVES

To evaluate the effects of negative-pressure ventilation (NPV) on hemodynamics using the Hayek oscillator (Breasy Medical Equipment, London, UK) and to determine whether the oscillation frequency can modify the hemodynamics, assessed by transesophageal echocardiography (TEE).

DESIGN

A prospective study.

SETTING

A university hospital.

PARTICIPANTS

Eleven American Society of Anesthesiologists class I patients undergoing orolaryngeal surgery.

INTERVENTIONS

The ultrasound probe was inserted under general anesthesia. After baseline measurements were determined during spontaneous breathing, the frequency was changed from 30 to 60 to 120 cycles/min, consecutively. The left ventricular end-diastolic area (LVEDA), end-systolic area (LVESA), fractional area change (LVFAC), and end-systolic wall stress (ESWS) were determined. The velocities of the pulmonary artery (PA) flow, pulmonary venous (PV) flow, and transmitral flow were measured by pulsed Doppler techniques.

MEASUREMENTS AND MAIN RESULTS

PaO2 increased and PaCO2 decreased significantly. NPV caused a significant increase in the LVEDA, whereas it did not significantly change the PA velocity. ESWS, an index of afterload, remained unchanged.

CONCLUSION

The authors conclude that NPV using the Hayek oscillator induces an increase in the LVEDA without any changes in PA velocity, suggesting increased transmural pressure rather than increased preload, and that the three different frequencies do not modify the effects on the hemodynamics.

The role of intraoperative echocardiography in valve surgery

The widespread use and popularity of intraoperative echocardiography (IOE) has resulted from advances in cardiac surgery, reparative procedures for valvular heart disease and, most specifically, mitral valve repair. IOE has grown exponentially and is becoming an integral part of the planning and evaluation of many types of surgical procedures such that it is now considered standard of care especially for the perioperative management of patients undergoing mitral and aortic valve repair. This article discusses the application of intraoperative echocardiography and focus specifically on valvular heart disease as this represents the most widely accepted indication for the procedure in current clinical practice.

Isolated diastolic heart failure--what is it?

Epidemiological evidence suggests that 20 to 40% of all patients with heart failure have normal systolic function. Isolated diastolic dysfunction may be the principle pathophysiological mechanism in these patients. The diagnosis of isolated diastolic heart failure is problematic and not merely based on demonstrating normal systolic function. The prognosis in isolated diastolic heart failure is more favourable than in systolic heart failure. At the present time, there is no licensed treatment for isolated diastolic heart failure and treatment is largely empirical.

Effects of volume loading on pulmonary venous flow and its relation to left atrial functions

Although pulmonary venous (PV) flow is closely related to left atrial (LA) pressure dynamics, few investigators have discussed it in relation to LA functions, i.e., reservoir, conduit, and booster pump functions. We examined changes in PV flow rate, LA dimension, and left ventricular filling volume in 11 dogs, and assessed the effects of multistaged volume loading on PV flow and LA functions. Systolic PV flow rate (S) increased significantly and reached a plateau, reflecting a limited LA reservoir function. Diastolic PV flow rate (D) increased significantly with an increase in LA pressure. S/D ratio increased non-significantly from 0.87 +/- 0.07 before volume loading to 0.96 +/- 0.08 until S reached a plateau and then decreased to 0.76 +/- 0.08 (p < 0.05) because of a significant increase in D without an increase in S at the higher stages of volume loading. During atrial contraction, increases in LA active shortening and left ventricular filling volume were limited, indicating a limited LA forward ejection. The difference between PV flow rate just before and at the end of atrial contraction increased and correlated positively with left ventricular end-diastolic pressure (r = 0.57, p < 0.01). PV flow varies according to the degree of volume loading and reflects LA functions, which exhibit limited increases in response to volume loading.

Gender Differences in Mitral Inflow Parameters of Doppler Echocardiography

BACKGROUND: Doppler echocardiographic parameters are useful in understanding cardiac function. Previous studies have evaluated the physiologic effects of heart rate, body position, and age on left ventricular (LV) Doppler inflow variables. OBJECTIVE: The aim of this study was to investigate the effect of gender on LV Doppler inflow variables. METHODS: A complete echocardiographic study was performed in the left lateral position on 25 male and 25 female normal subjects. The Doppler variables, of E and A wave velocities, acceleration and deceleration times of the E wave velocity, and cardiac chamber dimensions were measured. RESULTS: The aortic root size (3.2 +/- 0.4 vs 2.8 +/- 0.4 cm, P = 0.002), LV end systolic (2.8 +/- 0.3 vs 2.5 +/- 0.5 cm, P = 0.03), and LV end diastolic dimensions (5.0 +/- 0.4 vs 4.5 +/- 0.6 cm, P = 0.003) were larger in men compared to women. E wave deceleration time (233 +/- 40 vs 197 +/- 37 msec, P = 0.002) was longer in men compared to women. Using univariate analysis, deceleration time of the E wave was correlated with heart rate (P = 0.001), maximal A wave velocity (P = 0.007), acceleration time of the E wave (P = 0.01), LV systolic dimension (P = 0.03), maximal E wave velocity (P = 0.04), LV diastolic dimension (P = 0.06), and height (P = 0.07). E/A ratio, body surface area, age, weight, and left atrial dimension had no significant correlation with the deceleration time of the E wave. In the multivariate model, heart rate (P = 0.001) had the most significant (inverse) correlation with deceleration time of the E wave. CONCLUSIONS: In this cohort of subjects, there were significant differences in LV systolic and diastolic measurements and Doppler measurements of deceleration time of the E wave between men and women. The differences in Doppler measurements between men and women are most likely affected by the higher heart rate in women. Therefore, when interpreting deceleration time of the E wave, the effect of heart rate should be considered.

Left ventricular diastolic function after coronary artery bypass grafting: a correlative study with three different myocardial protection techniques

BACKGROUND

This study was designed to examine the effect of myocardial protection on diastolic function after cardiac operations.

METHODS

Subjects were patients with normal preoperative diastolic function who were scheduled for coronary artery bypass grafting. Group I received anterograde cardioplegia; group II received anterograde and retrograde cardioplegia; and group III was protected with ventricular fibrillation and intermittent aortic crossclamping. Operations were performed with mild hypothermia and ventricular venting through the left superior pulmonary vein in all cases. Left ventricular diastolic function was evaluated with pulsed-wave Doppler transesophageal echocardiography (samples at the mitral valve leaflet: four-chamber view) and left superior pulmonary vein flow velocity. The flow patterns were stored on videotape and sent to an independent investigator for analysis. Left ventricular ejection fraction was calculated with transesophageal echocardiography (short-axis view, two-dimensional and M-mode).

RESULTS

Left ventricular diastolic function, as measured by the ratio between the peak velocities during early filling and atrial contraction and by systolic diastolic superior pulmonary venous flow ratio, was significantly impaired in all three groups 5 minutes after discontinuation of cardiopulmonary bypass. At 1 hour after operation, these values had returned to control levels only in group III. There was an increased incidence of supraventricular arrhythmias in group III. There were no significant hemodynamic differences among the three groups.

CONCLUSIONS

Left ventricular diastolic function was severely impaired after cardiopulmonary bypass. The degree of impairment depended on the myocardial protection used. The impairment in diastolic function was less when ventricular fibrillation and intermittent aortic crossclamping were used, and greater when anterograde and retrograde cardioplegia were used.

Utility of preload alteration in assessment of left ventricular filling pressure by Doppler echocardiography: a simultaneous catheterization and Doppler echocardiographic study

OBJECTIVES

The aim of this study was to demonstrate the usefulness of preload alterations in assessing left ventricular filling pressures with transmitral Doppler velocity curves.

BACKGROUND

Doppler mitral inflow velocities, used to estimate left ventricular filling pressures noninvasively, are limited in predicting left ventricular filling pressures, especially in patients with normal systolic function and a "pseudonormal" mitral filling pattern.

METHODS

Forty-nine patients were studied in the cardiac catheterization laboratory with simultaneous Doppler echocardiography using high fidelity catheters to compare left ventricular diastolic filling pressures (pre-A wave left ventricular pressure) and Doppler mitral inflow at baseline and during reduction of preload during the strain phase of the Valsalva maneuver (n = 27) or sublingual nitroglycerin (n = 36), or both (n = 14). Doppler measurements consisted of E (initial peak velocity), A (velocity at atrial contraction), deceleration time (time from E velocity to deceleration of flow extrapolated to baseline) and absolute A wave velocity (A' [peak A wave velocity minus velocity at onset of atrial contraction]).

RESULTS

In patients with high pre-A wave pressure (> or 15 mm Hg), there was a greater change in the E/A' ratio during the Valsalva maneuver than in patients with a normal pre-A wave pressure (-1.22 +/- 1.1 vs. -0.35 +/- 0.17; p = 0.02). A similar change was seen when comparing the change in the E/A' ratio after administration of nitroglycerin in patients with a high versus a normal pre-A wave pressure (0.81 +/- 0.49 vs. 0.18 +/- 0.17; p < 0.001). These differences were present in patients with a normal E/A ratio at baseline.

CONCLUSIONS

Alterations in preload during assessment of Doppler echocardiographic indexes may be useful in noninvasively assessing left ventricular filling pressures.

Evaluation of diastolic filling of left ventricle in health and disease: Doppler echocardiography is the clinician's Rosetta Stone

Abnormalities of diastolic function have a major role in producing the signs and symptoms of heart failure. However, diastolic function of the heart is a complex sequence of multiple interrelated events, and it has been difficult to understand, diagnose and treat the various abnormalities of diastolic filling that occur in patients with heart disease. Recently, Doppler echocardiography has been used to examine the different diastolic filling patterns of the left ventricle in health and disease, but confusion about diagnosis and treatment options has arisen because of the misinterpretation of these flow velocity curves. This review presents a simplified approach to understanding the process of diastolic filling of the left ventricle and interpreting the Doppler flow velocity curves as they relate to this process. It has been hypothesized that transmitral flow velocity curves show a progression over time with diseases involving the myocardium. This concept can be applied clinically to estimate left ventricular filling pressures and to predict prognosis in selected groups of patients. Specific therapy for diastolic dysfunction based on Doppler flow velocity curves is discussed.

Noninvasive doppler echocardiographic evaluation of left ventricular filling pressures in patients with cardiomyopathies: a simultaneous Doppler echocardiographic and cardiac catheterization study

OBJECTIVES

The purpose of this study was to examine the relation of the mitral flow velocity curves to left ventricular filling pressures in patients with two different types of myocardial problems: hypertrophic cardiomyopathy and severe left ventricular systolic dysfunction.

BACKGROUND

Previous studies have suggested that assessment of Doppler-derived mitral flow velocity curves can be used to predict left ventricular filling pressures in specific disease entities. However, it is unclear whether information derived from specific mitral flow velocity curves obtained from one disease entity can be valid in other disease states.

METHODS

The study group consisted of 42 patients with left ventricular systolic dysfunction (group A) and 55 patients with hypertrophic cardiomyopathy (group B); both groups underwent simultaneous cardiac catheterization and were studied by Doppler echocardiography. High fidelity measures of left atrial and left ventricular pressures were obtained simultaneously with mitral flow velocity curves.

RESULTS

There was a significant relation between the Doppler echocardiographic variables and mean left atrial pressure in group A patients. The left atrial pressure was directly related to the E/A ratio (r = 0.49, p = 0.004) and inversely related to the deceleration time (r = 0.73, p < 0.001). The sensitivity and specificity of the deceleration time, < 180 m/s, which indicated a mean left atrial pressure > or = 20 mm Hg, were both 100%. In group B patients, there was no significant relation between mean left atrial pressure and deceleration time.

CONCLUSIONS

Doppler echocardiographic mitral flow velocity curves are useful in predicting and estimating left ventricular filling pressures in patients with left ventricular dysfunction. However, because of the complexity of the multiple interrelated factors that determine diastolic filling of the left ventricle, these flow velocity curves cannot be used in patients with other disease entities, such as hypertrophic cardiomyopathy. Future studies of different disease states are necessary to fully understand the role of Doppler echocardiography in the assessment of diastolic filling.

ACE inhibitors unmask incoordinate diastolic wall motion in restrictive left ventricular disease

OBJECTIVE

To assess the effect of ACE-inhibition on left ventricular filling and wall motion in patients with a clinical diagnosis of heart failure.

DESIGN

Prospective examination of left ventricular systolic and diastolic function using M mode echocardiography and pulsed and continuous wave Doppler before and three weeks after starting an ACE inhibitor.

SETTING

A tertiary referral centre for cardiac disease equipped with non-invasive facilities.

SUBJECTS

30 outpatients with a clinical diagnosis of heart failure in whom treatment with an ACE inhibitor was started; age 61 (SD 11) years; 27 male; 3 female; 21 healthy controls of similar age.

RESULTS

Left ventricular cavity was dilated both at end systole and end diastole, and fractional shortening reduced. Although mean isovolumetric relaxation time (IVRT) and transmitral E (early) to A (late) filling velocity (E/A) ratio were not different from normal, a value of 1.0 on the normal frequency plot of the E/A ratio divided the patients bimodally into two groups: 20 patients (group A) with E/A ratio > 1.0 and 10 patients (group B) < 1.0. In group A patients, IVRT was short as was transmitral E wave deceleration time compared to normal (P < 0.001), fulfilling the criteria of restrictive left ventricular physiology. Left ventricular wall motion during IVRT was coordinate and left ventricular end diastolic pressure was raised on the apex-cardiogram (P < 0.001). In group B, E wave deceleration time was longer, relaxation incoordinate, and apexcardiogram normal. With an ACE inhibitor: in group A, left ventricular dimensions fell at end diastole (P < 0.05) and end systole (P < 0.01) but fractional shortening did not change; long axis total excursion (P < 0.01) and peak rate of shortening (P < 0.05) both increased; IVRT increased (P < 0.001) with the appearance of markedly incoordinate wall motion, minor axis lengthening, and long axis shortening (P < 0.001 for both); A wave amplitude also consistently increased (P < 0.001); finally, transmitral E wave velocity fell and A wave velocity increased. ACE inhibition did not alter any of the left ventricular minor and long axis or transmitral Doppler variables in patients in group B.

CONCLUSIONS

Patients with a clinical diagnosis of heart failure differ in their presentation and response to ACE inhibition according to baseline haemodynamics. In restrictive left ventricular physiology, ACE inhibition reduces cavity size and prolongs IVRT, compatible with a fall in left atrial pressure. At the same time, ventricular relaxation becomes very delayed and incoordinate, greatly reducing early diastolic left ventricular filling velocity. Thus ACE inhibition unmasks major diastolic abnormalities in patients with restrictive left ventricular disease.

A practical guide to assessment of ventricular diastolic function using Doppler echocardiography

Doppler assessment of diastolic function has become a standard part of routine echocardiographic examination and imparts information relevant to a patient's functional class, management and prognosis. This review describes the Doppler patterns of diastolic function relative to physical signs and physiology. A continuum of doppler patterns of diastolic function exists, including normal diastolic function, impaired relaxation, pseudonormal filling, restriction, constriction and tamponade. These patterns evolve from one to another in a single individual, with changes in disease evolution, treatment and loading conditions. New applications of continuous wave Doppler, color Doppler M-mode and Doppler tissue imaging are refining our understanding of diastolic function.

Echocardiographic assessment of left ventricular filling during isoflurane anaesthesia

PURPOSE

To determine the effect of isoflurane on left ventricular diastolic function, as assessed by Doppler echocardiography.

METHODS

Ten patients with normal cardiovascular function were enrolled. Doppler measurements of mitral inflow velocities, and pulmonary venous blood flow velocities were measured preoperatively (transthoracic echocardiography), and intraoperatively (transesophageal echocardiography) at isoflurane MAC 1 and MAC 1.5. Heart rate and blood pressure were measured concomitantly. Variables were compared with repeated measures ANOVA.

RESULTS

Isoflurane at both doses caused equal decreases in mitral inflow A(atrial systole) velocity (control: 43 +/- 12.3 cm.sec-1 vs MAC 1: 31 +/- 6.0 cm.sec-1 and MAC 1.5: 31.3 +/- 7.9 cm.sec-1 P < 0.01), the deceleration time of the mitral inflow E (early) velocity (control: 178 +/- 31.7 msec versus MAC 1: 127 +/- 38.3 msec and MAC 1.5: 137 +/- 28.4 msec, P < 0.01), and mean blood pressure (control: 91.1 +/- 15.4 mmHg versus MAC 1: 76.1 +/- 8.8 mmHg and MAC 1.5: 71.9 +/- 6.2 mmHg, P < 0.002). Isoflurane at both doses caused an equal increase in the E/A ratio (control: 1.5 +/- 0.57 vs MAC 1: 2.0 +/- 0.6 and MAC 1.5: 2.2 +/- 0.78, P < 0.01). No changes in mitral inflow E or pulmonary venous velocities were seen.

CONCLUSION

The changes in Doppler velocities of mitral inflow and pulmonary venous flow with isoflurane are not consistent with prolonged left ventricular relaxation nor increased myocardial restriction, but are more likely the result of alterations in left ventricular loading conditions and atrial systolic function.

Assessment of pulmonary venous and transmitral flow in closed-chest dogs under various loading conditions by transesophageal Doppler echocardiography

Pulmonary venous flow velocity (PVFVe), pulmonary venous dimension (PVD) and transmitral flow (TMF) velocity were examined under various loading conditions in 15 anesthetized closed-chest dogs by transesophageal Doppler echocardiography (TEE). We also compared PVFVe with pulmonary venous flow volume (PVFVo) simultaneously in open-chest dogs using an ultrasonic flow probe. PVFVo decreased by more than 50% and PVD also decreased significantly during preload reduction, while there was no change in PVFVe. This discrepancy between PVFVo and PVFVe was apparently due to the collapse of pulmonary veins. TMF consisted of both rapid-filling flow velocity and atrial flow velocity components (R and A), while PVF consisted of systolic and diastolic forward flow velocity components (S and D). The peak values of R,A,S and D and the time-velocity integrals of each wave (RI, AI, SI and DI, respectively) were measured. There was a significant correlation between the changes in RI and SI/DI during preload reduction (r = 0.82, p < 0.001) and during after-load increase (r = -0.59, p < 0.05). These results suggest that changes in RI with different loading conditions might be attributable to changes in atrial reservoir volume and conduit volume.

Comparison between transesophageal Doppler echocardiography and nuclear cardioangiography for the evaluation of left ventricular filling during coronary artery bypass grafting

This study examines the relative contribution of early (E) and atrial (A) filling of the left ventricle. Ten patients were studied under anesthesia before and after coronary artery bypass grafting (CABG) using measurements of the mitral velocity-time integral (VTI) with transesophageal pulsed Doppler echocardiography and nuclear angiocardiography simultaneously. Thermodilution cardiac output measurements were made simultaneously in order to express the E and A filling in quantitative terms. The mean difference between methods in estimating E filling was -1.0 mL and the figures for the mean +/- 2 SD were 5.7 and -7.8 mL, r = 0.98 using regression analysis. The mean difference during A filling was 0.9 mL and the corresponding figures for the mean +/- 2 SD were 7.9 and -6.1 mL, r = 0.88. There was a reduction in the volume entering the left ventricle during the E filling (42-26 mL) and in the A phase (27-22 mL) from before surgery in comparison to after CABG. There was good agreement between transesophageal Doppler echocardiographic and nuclear angiocardiographic methods concerning the volume contribution during E and A phases of left ventricular filling.

Effects of adenosine infusion on systolic and diastolic left ventricular function after coronary artery bypass surgery: evaluation by computer-assisted quantitative 2-D and Doppler echocardiography

The effects of adenosine on central hemodynamics, ST-segment changes, and left ventricular (LV) systolic and diastolic function, determined by transesophageal 2-D and Doppler echocardiography, were investigated in 20 patients shortly after coronary surgery. After control measurements, adenosine was infused at incremental infusion rates (30, 60, and 120 micrograms.kg-1.min-1). Adenosine caused dose-dependent increases in heart rate (68.0 +/- 11.2-74.0 +/- 15.7 bpm), cardiac output (3.23 +/- 0.76-4.17 +/- 0.67 L/min), and stroke volume (48.8 +/- 12.5-56.7 L/min), and stroke volume (48.8 +/- 12.5-56.7 mL), decreases in arterial pressure (84.8 +/- 16.6-63.3 +/- 15.2 mm Hg), and systemic and pulmonary vascular resistances (1994 +/- 510-1106 +/- 309 and 209 +/- 54-116 +/- 58 dyne.s.cm-5, respectively), but no changes in cardiac filling pressures. The mean ST segment was slightly but significantly depressed by adenosine (from 0.003 to 0.019 mV). Analysis of LV wall motion showed that adenosine caused no changes in the global area ejection fraction (GAEF), the segmental area ejection fraction (SAEF), or in the SAEF/GAEF ratio, indicating that no regional wall motion abnormalities appeared. Maximum early and late diastolic flow rates (Emax, Amax), determined by mitral Doppler analysis, increased (from 30.1 +/- 14.8 to 40.1 +/- 24.1 and from 37.8 +/- 15.7 to 46.4 +/- 31.3 cm/s, respectively), as did the deceleration slope of the early diastolic filling (from -151 +/- 67 to -210 +/- 107 cm/s-2), whereas no changes were found in the ratio between Emax and Amax, the deceleration time of early diastolic filling, or the velocity time integrals of early or late diastolic filling.(ABSTRACT TRUNCATED AT 250 WORDS)