Recommendations for quantification of Doppler echocardiography: a report from the Doppler Quantification Task Force of the Nomenclature and Standards Committee of the American Society of Echocardiography

Maximal Longitudinal Contraction Velocity in Assessment of Left Ventricular Systolic Function: A Pulsed Tissue Doppler and M-Mode Study

AIMS

During recent years the maximal longitudinal contraction velocity (MLCV), measured by either pulsed tissue Doppler or M-mode, has been suggested as an index of left ventricular (LV) systolic function. The aims of the present study were to compare MLCV with ejection fraction (EF) in consecutive patients with known or suspected heart failure and to compare measures from recordings by pulsed tissue Doppler with recordings by M-mode.

METHODS AND RESULTS

Sixty-four consecutive patients with suspected or known heart failure, referred to echocardiography, were included. Twelve of these patients had decreased LV systolic function defined as EF < 50% calculated by the biplane Simpson's rule, while a significantly (P > 0.05) higher proportion of 23 had decreased function defined as decreased MLCV recorded by pulsed tissue Doppler. Measures from M-mode recordings were significantly lower (P < 0.001) than the corresponding measures from tissue Doppler recordings.

CONCLUSIONS

The study shows that higher values of MLCV are obtained by pulsed tissue Doppler than by M-mode. Reference values can therefore not be used interchangeably. The results also suggest that MLCV is a more sensitive index of LV systolic function than EF.

Relation of Biventricular Function Quantified by Stress Echocardiography to Cardiopulmonary Exercise Capacity in Adults With Mustard (Atrial Switch) Procedure for Transposition of the Great Arteries

BACKGROUND

Mustard repair for transposition of the great arteries (TGA) is frequently associated with impaired systemic (right) ventricular function and sometimes exercise intolerance. We hypothesized that a simple quantitative measurement of ventricular function, during rest and pharmacological stress, could identify abnormalities and predict objective exercise capacity.

METHODS AND RESULTS

We quantified the performance of systemic and pulmonary (left) ventricles by using echocardiography, at rest and during dobutamine stress, in 27 adults who had undergone Mustard repair for TGA. Systolic and diastolic function of the systemic ventricle were markedly disturbed with respect to pulmonary ventricular function. We also measured exercise capacity by cardiopulmonary exercise testing for peak oxygen uptake. Exercise capacity was significantly predicted by systemic ventricular long-axis excursion both at rest (r=0.66, P<0.001) and at peak dobutamine stress (r=0.53, P=0.006) but not by pulmonary ventricular long-axis excursion at rest (r=0.04) or on stress (r=0.11). Exercise capacity was also predicted by the septal long-axis excursion at rest (r=0.61, P=0.001) but not pulmonary ventricular free wall excursion (P>0.05) or fractional shortening (P>0.05). Peak aortic velocity at maximum dobutamine stress correlated with exercise capacity (r=0.46, P=0.029) but not at rest (r=0.36). Multivariate analysis revealed systemic ventricular long-axis excursion to be the sole significant independent predictor of exercise capacity.

CONCLUSIONS

Systemic ventricular function is depressed in most patients with Mustard repair. Quantitative echocardiographic evaluation shows systemic ventricular function to be a key determinant of exercise capacity.

Transition From Epoprostenol and Treprostinil to the Oral Endothelin Receptor Antagonist Bosentan in Patients With Pulmonary Hypertension

STUDY OBJECTIVES

Prior to the availability of the oral endothelin antagonist bosentan, most patients with pulmonary arterial hypertension (PAH) were treated with continuously infused prostacyclins. Many patients receiving prostacyclins would have received bosentan if it had been available at the time of their diagnosis. Noninvasive criteria (symptoms, World Health Organization [WHO] functional class, 6-min walk test [6MWT] distances, and echocardiograms) are used to govern up-titration of prostacyclins and to assess response to bosentan. The purposes of this study were to see if some patients might be able to transition safely from prostacyclin to bosentan, and whether noninvasive criteria could be used to monitor this transition.

METHODS

From January 2002 to July 2003, 23 stable patients with PAH attempted a transition from prostacyclin to bosentan over an 8-week period. 6MWT results, WHO class, and echocardiograms were recorded prior to transition and 1 month after successful transition. The transition was stopped and prostacyclin was resumed or up-titrated if any symptoms of PAH worsened.

RESULTS

Of 23 candidates (19 female and 4 male; age range, 17 to 73 years), 15 patients were transitioned to bosentan. Of these patients, four patients experienced worsening symptoms (range, 7 weeks to 12 months after cessation of prostacyclin) and resumed treatment with prostacyclin. Of the remaining 11 patients, 2 patients had liver function abnormalities 3 months and 10 months after transition to bosentan, respectively; 9 patients remained on bosentan 3 to 16 months after prostacyclin cessation. Patients failing transition and resuming prostacyclin returned to their pretransition functional baseline.

CONCLUSION

Nine of 23 carefully selected, stable patients with PAH receiving long-term prostacyclin were successfully transitioned to oral bosentan using noninvasive monitoring. No long-term adverse events were associated with failed transition attempts. Further studies need to be carried out to determine which patients are more likely to undergo the transition successfully.

Long-term prognostic significance of left atrial volume in acute myocardial infarction

OBJECTIVES

The aim of this study was to evaluate the significance of increased left atrial (LA) volume determined within the first 48 h of admission as a long-term predictor of outcome in patients with acute myocardial infarction (MI).

BACKGROUND

The LA volume reflects left ventricular (LV) diastolic properties. Whereas other LV Doppler diastolic characteristics are influenced by acute changes in LV function, LA volume is stable and reflects diastolic properties before MI.

METHODS

Clinical and echocardiographic parameters were prospectively collected in 395 consecutive patients with acute MI. Patients with LA volume index (LAVI) >32 ml/m(2) (normal + 2 standard deviations) were compared with those with LAVI <==32 ml/m(2). Independent clinical and echocardiographic prognostic risk factors for five years' mortality were determined by the Cox proportional hazard model.

RESULTS

Left atrial volume index >32 ml/m(2) was found in 63 patients (19%) who had a higher incidence of congestive heart failure on admission (24% vs. 12%, p < 0.01), a higher incidence of mitral regurgitation, increased LV dimensions, and reduced LV ejection fraction when compared with patients with LAVI <==32 ml/m(2). Their five-year mortality rate was 34.5% versus 14.2% (p < 0.001). Significant independent risk predictors of five years' mortality were age (10 years) (odds ratio [OR] 1.45; 95% confidence interval [CI]1.14 to 1.86), Killip class >/=2 on admission (OR 2.30; 95% CI 1.29 to 4.09), LAVI >32 ml/m(2) (OR 2.22; 95% CI 1.25 to 3.96), diabetes (OR 1.94; 95% CI 1.15 to 3.28), and LV restrictive filling pattern (OR 1.89; 95% CI 1.09 to 3.31).

CONCLUSIONS

In patients with acute MI, increased LA volume, determined within the first 48 h of admission, is an independent predictor of five-year mortality with incremental prognostic information to clinical and echocardiographic data.

Comprehensive transthoracic cardiac imaging in mice using ultrasound biomicroscopy with anatomical confirmation by magnetic resonance imaging

High-frequency ultrasound biomicroscopy (UBM) has recently emerged as a high-resolution means of phenotyping genetically altered mice and has great potential to evaluate the cardiac morphology and hemodynamics of mouse mutants. However, there is no standard procedure of in vivo transthoracic cardiac imaging using UBM to comprehensively phenotype the adult mice. In this paper, the characteristic mouse thoracic anatomy is elucidated using magnetic resonance (MR) imaging on fixed mice. Besides the left parasternal and apical windows commonly used for transthoracic ultrasound cardiac imaging, a very useful right parasternal window is found. We present strategies for optimal visualization using UBM of key cardiac structures including: 1) the right atrial inflow channels such as the right superior vena cava; 2) the right ventricular inflow tract via the tricuspid orifice; 3) the right ventricular outflow tract to the main pulmonary artery; 4) the left atrial inflow channel, e.g., pulmonary vein; 5) the left ventricular inflow tract via the mitral orifice; 6) the left ventricular outflow tract to the ascending aorta; 7) the left coronary artery; and 8) the aortic arch and associated branches. Two-dimensional ultrasound images of these cardiac regions are correlated to similar sections in the three-dimensional MR data set to verify anatomical details of the in vivo UBM imaging. Dimensions of the left ventricle and ascending aorta are measured by M-mode. Flow velocities are recorded using Doppler at six representative intracardiac locations: right superior vena cava, tricuspid orifice, main pulmonary artery, pulmonary vein, mitral orifice, and ascending aorta. The methodologies and baseline measurements of inbred mice provide a useful guide for investigators applying the high-frequency ultrasound imaging to mouse cardiac phenotyping.

Comparison of right and left ventricular function in obese and nonobese men

We studied systolic and diastolic function of the left and right ventricles in obese male subjects. Obese subjects had increased left ventricular mass and normal left ventricular systolic and diastolic function. They also had impaired right ventricular relaxation and right ventricular filling.

Alterations in left ventricular structure and function in young healthy obese women: assessment by echocardiography and tissue Doppler imaging

OBJECTIVES

This study was designed to determine the effects of obesity on left ventricular (LV) structure and function in young obese women.

BACKGROUND

Severe prolonged obesity in older adults results in increased plasma volume, eccentric LV hypertrophy, and systolic and diastolic dysfunction. Obese women are at increased risk for the development of heart failure. However, the effects of the obesity on cardiac structure and function in young, otherwise-healthy women are controversial.

METHODS

Fifty-one women were evaluated: 20 were obese (body mass index [BMI] > or =30 kg/m(2)) and 31 were non-obese (BMI <30 kg/m(2)). Left ventricular structure and systolic and diastolic function were assessed by two-dimensional echocardiography and tissue Doppler imaging, including the load-independent systolic myocardial velocity (Sm global) and early diastolic myocardial velocity (Em global), respectively. The effects of BMI on LV structure and function were assessed using multivariate regression analyses.

RESULTS

Obese women had higher end-diastolic septal and posterior wall thickness, LV mass, and relative wall thickness than non-obese women; BMI values showed significant correlations with these variables (r = 0.58, p < 0.0001; r = 0.50, p < 0.0002; r = 0.52, p < 0.0001, and r = 0.40, p < 0.005, respectively). The Sm global and Em global were lower in obese women, suggesting systolic and diastolic function are decreased; both were negatively correlated with BMI (r = -0.43, p <. 002 and r = -0.61, p < 0.0001, respectively). Multivariate analysis showed BMI was the only independent predictor of relative wall thickness, Sm global, and Em global.

CONCLUSIONS

Obesity in young otherwise-healthy women is associated with concentric LV remodeling and decreased systolic and diastolic function. These early abnormalities in LV structure and function may have important implications for explaining the myocardial dysfunction that is associated with increased cardiovascular morbidity and mortality caused by obesity.

Noninvasive assessment of ejection intraventricular pressure gradients

OBJECTIVES

The study was designed to validate in vivo a new method to measure ejection intraventricular pressure gradients (IVPGs) by processing color M-mode Doppler data and to assess the effects of inotropic interventions on IVPGs in the clinical setting.

BACKGROUND

In the absence of obstruction, ejection IVPGs cannot be estimated by Doppler using the simplified Bernoulli equation.

METHODS

High-fidelity micromanometers were placed in the left ventricle of eight minipigs, and synchronic Doppler images and pressure signals were obtained during different hemodynamic conditions. Twenty healthy volunteers and 20 dilated cardiomyopathy patients were studied at baseline and during esmolol, dobutamine, and atropine infusion (only dobutamine in patients).

RESULTS

Excellent agreement was observed between micromanometer and Doppler methods for measuring instantaneous pressure differences among the apex, the mid-cavity, and the outflow tract (R(intraclass) = 0.98, 0.81, 0.76, and 0.98 for the peak, time-to-peak, peak reverse, and time-to-peak reverse values, respectively; n = 810 beats). Error of the noninvasive method was -0.05 +/- 0.25 mm Hg for the peak pressure difference. Parametrical images demonstrated that IVPGs originate mainly in the mid-ventricle and then propagate to the outflow tract. Both the magnitude and the temporal course of IVPGs were different among volunteers and patients. Inotropic interventions induced significant changes in the apex-outflow tract pressure differences in both populations, whereas atropine had no effect on IVPGs.

CONCLUSIONS

For the first time, ejection IVPGs can be accurately visualized and measured by Doppler-echocardiography. Important aspects of the dynamic interaction among myocardial performance, load mechanics, and ejection dynamics can be assessed in the clinical setting using this method.

Usefulness of echocardiographic tissue synchronization imaging to predict acute response to cardiac resynchronization therapy

Echocardiographic tissue synchronization imaging (TSI) consists of color-coding time-to-peak tissue Doppler velocities. This study of 29 patients who underwent cardiac resynchronization therapy (CRT) demonstrated that differences in baseline time-to-speak velocities of opposing ventricular walls by TSI were greater in 15 patients, with an acute hemodynamic improvement. A >/=65 ms delay from the anterior septum to the posterior wall using the apical long-axis view had 87% sensitivity and 100% specificity for predicting an acute response. Although a subgroup without acute improvement had later decreases in end-systolic volume, suggesting that acute response underestimates long-term effects, TSI has potential to assist in guiding CRT.

Pulsed tissue Doppler imaging detects early myocardial dysfunction in asymptomatic patients with severe mitral regurgitation

OBJECTIVE

To assess whether tissue Doppler myocardial imaging (TDI) indices can predict postoperative left ventricular function in patients with mitral regurgitation (MR) after surgical correction.

METHODS

84 patients (mean (SD) age 54.3 (10.8) years) with asymptomatic severe MR, an end systolic diameter < 45 mm, and an ejection fraction (EF) > 60% were subdivided in two groups: 43 patients with a postoperative EF reduction < 10% (group 1) and 41 patients with a postoperative EF reduction > or = 10% (group 2).TDI systolic indices of the lateral annulus were analysed preoperatively to assess myocardial systolic wave (Sm) velocity, myocardial precontraction time (PCTm), myocardial contraction time (CTm), and the PCTm:CTm ratio.

RESULTS

Postoperative EF decreased significantly (from 67 (5)% to 60 (5.5)%, p = 0.0001). Group 2 had a higher PCTm, CTm, and PCTm:CTm ratio and a lower Sm velocity than group 1 (PCTm 100.4 (19) ms v 82 (21.8) ms, p = 0.004; CTm 222 (3.1) ms v 215 (2.3) ms, p = 0.01; PCTm:CTm 0.45 (0.08) v 0.38 (0.09), p = 0.001; Sm velocity 10.4 (1.1) cm/s v 13 (1.3) cm/s, p = 0.0001). Multivariate regression analysis showed that the combination of PCTm:CTm ratio > or = 40 ms and Sm velocity < or = 10.5 cm/s was the main independent predictor of postoperative EF reduction > or = 10% (sensitivity 78%, specificity 95%).

CONCLUSIONS

TDI systolic indices can predict postoperative left ventricular function in patients with asymptomatic MR undergoing surgical correction.

Mechanisms of Exercise Intolerance

Background— A decreased ratio of early to late diastolic mitral inflow velocities (E/A <1.0) reflects slowing of left ventricular (LV) relaxation. This finding is widely believed to indicate significant diastolic dysfunction. However, E/A <1.0 is common during normal aging and often is not associated with symptoms of heart failure. We asked (1) whether slowed LV relaxation is associated with exercise intolerance and (2) whether tissue Doppler imaging of the early diastolic mitral annular velocity (Ea) is helpful in understanding mechanisms of exercise intolerance.

Methods and Results— Patients (n=121) underwent echocardiography before maximal exercise testing. Fifty-nine subjects had E/A <1.0, and 36 subjects had E/Ea ≥10. Exercise capacity was similar in the population with a normal mitral inflow pattern and those with a slow relaxation pattern when E/Ea was <10. In contrast, the subjects with slow relaxation and E/Ea ≥10 had reduced exercise tolerance. Of all the echo and clinical parameters assessed, E/Ea had the best correlation with exercise capacity ( r =−0.684, P <0.001) and was the strongest independent predictor of exercise capacity ≤7 METs by multivariate analysis (prevalence-corrected odds ratio=12.6, P <0.001). E/Ea continued to be strongly associated with exercise capacity in all age groups and in those with preserved or reduced systolic function.

Conclusions— Of the subjects with slow LV relaxation, only those with E/Ea ≥10 have objective evidence of reduced exercise tolerance. These data suggest that elevated LV filling pressures rather than slow relaxation per se reduce exercise capacity.

Color flow imaging of the vena contracta in mitral regurgitation: technical considerations

Qualitative grading of mitral regurgitation severity has significant pitfalls secondary to hemodynamic variables, sonographic technique, blood pool entrainment, and the Coanda effect. Volumetric and proximal isovelocity surface area methods can be used to quantitate regurgitant orifice area, regurgitant volume, and regurgitant fraction, but have several limitations and can pose technical challenges. The vena contracta width method provides a rapid and accurate quantitative assessment of mitral regurgitation severity, but is clinically underused. This article is intended to generate an understanding of the flow mechanics of the vena contracta and the sonographic technique required to provide consistent and accurate measurements of vena contracta width in patients with mitral regurgitation.

Portable spectral Doppler echocardiographic device: overcoming limitations

BACKGROUND

There is evidence that new portable echocardiographic devices are useful in evaluating heart anatomy and function, but a lack of Doppler modes has up to now been an important limitation in obtaining haemodynamic data.

OBJECTIVES

To report the Doppler capabilities of a new hand held echocardiographic device.

DESIGN

Blinded comparison of two types of echocardiography machine.

SETTING

Tertiary care centre.

PATIENTS

98 consecutive patients were randomly imaged with the hand held device, with a standard platform as reference.

OUTCOME MEASURES

Pulsed wave transmitral Doppler inflow tract velocities, deceleration time, and continuous wave Doppler measurements of aortic ejection and tricuspid regurgitation peak velocities were recorded.

RESULTS

There was excellent agreement between the hand held device and standard echocardiography for the evaluation of diastolic E and A waves, E/A ratio, and deceleration time with pulsed wave Doppler (intraclass correlation coefficients of 0.97, 0.93, 0.90, and 0.78, respectively). In addition, good agreement was found between continuous wave Doppler measurements of aortic ejection and tricuspid regurgitation velocities (intraclass correlation coefficients of 0.96 and 0.80). However, there was a significant difference between patients with tricuspid regurgitation measured with the hand held device (25.5%) and by standard echocardiography (65.3%), resulting in misdiagnosis of eight patients with pronounced pulmonary hypertension.

CONCLUSIONS

New hand held devices with Doppler capabilities overcome previous limitations in evaluating haemodynamic variables. With colour Doppler they are now suitable for the complete evaluation of valvar disease and diastolic function. However, important limitations remain in the evaluation of pulmonary pressures.

Noninvasive assessment of hemodynamic parameters in experimental stenosis of the ascending aorta

We sought to noninvasively evaluate left ventricular (LV) function after cardiac hypertrophy induced by experimental stenosis of the ascending aorta. Male Wistar rats (70-90 g) underwent ascending aorta constriction by the surgical placement of a titanium clip (n=5) or sham operation (n=6). High-resolution bidimensional, pulsed-wave Doppler (PWD) and pulsed-wave tissue Doppler imaging (TDI) were performed 22 weeks after surgery. PWD was used to obtain mitral flow velocities, and TDI was used to obtain velocities along the septal mitral annulus and LV posterior wall. Clip placement produced myocardial hypertrophy with decreased systolic myocardial peak velocity in both the long and short axes. Increased myocardial mass, that is, posterior wall and septal thickness, was indicative of ventricular remodeling. Diastolic dysfunction was observed, with an increased early to late ratio of mitral velocities and increased left atrium dimension, consistent with a left ventricular restrictive filling pattern.

Allelic variants of natriuretic peptide receptor genes are associated with family history of hypertension and cardiovascular phenotype

OBJECTIVE

Abnormalities in the natriuretic peptide system could play a key role in the genesis of hypertension. We evaluated the associations between a family history of hypertension, cardiovascular phenotype and allelic variants of Npr1 and Npr3, two candidate genes that codify for natriuretic peptide receptors.

METHODS

We genotyped 45 young normotensive subjects (19 males, 26.8 +/- 3.7 years) with accurately assessed family history of hypertension (FH+) and 52 (26 males, 26.1 +/- 3.1 years) without (FH-) for the known variants of Npr1 and Npr3 genes, and for a novel length difference (3C/4C) polymorphism at position 15129 in the 3'-untranslated region of the Npr1 gene. Blood pressure, echocardiography and plasma brain natriuretic peptide were assessed.

RESULTS

Both the novel Npr1 3C allele (59 versus 33%, P < 0.001) and the 3C/3C genotype (31 versus 8%; P < 0.001) were significantly more frequent in FH+ than in FH-. The inverse distribution of the 4C/4C genotype suggested that a casual association was very unlikely. Moreover, the 3C/3C homozygous had significantly higher systolic blood pressure (121.1 +/- 6.3 versus 115.6 +/- 7.8 mmHg in 4C/4C; P < 0.05) and a longer left ventricular isovolumic relaxation time (67 +/- 10 versus 61 +/- 9 ms; P < 0.05). The Npr3 C(-55) allele variant was also more frequent in FH+ (88 versus 76%, P < 0.05), but was not associated with the cardiovascular phenotype.

CONCLUSIONS

The novel Npr1 gene 3C variant and the Npr3 gene C(-55) allele are associated with hypertensive family history. Moreover, the functional Npr1 3C variant, when homozygous, is also associated with higher systolic blood pressure and prolonged ventricular relaxation.

Ultrasound biomicroscopy-Doppler in mouse cardiovascular development

The ability to modify the mouse genome has yielded new insights into the genetic control of mammalian cardiovascular development. However, it is far less understood how genetic factors and their consequent structural changes alter cardiovascular function, a void largely due to the lack of effective noninvasive techniques to assess function in the developing mouse cardiovascular system. In this review, we discuss the recent advances in ultrasound biomicroscopy (UBM)-Doppler echocardiography for analyzing cardiovascular function in the embryonic mouse in utero. "Cardiovascular function" encompasses broad aspects of physiology, including systolic and diastolic cardiac function, distribution of blood flow among various embryonic vascular beds, and vascular bed properties (impedance). A wide range of physiological measurements is possible using UBM-Doppler, but it is clear that the limitations of any single measurement warrant a multi-parameter approach to characterizing cardiovascular function. We further discuss the prospects for UBM-Doppler analysis of alternative vertebrate systems increasingly studied in developmental biology. The ability to correlate cardiovascular physiological phenotypes with their corresponding genotypes should lead to the elucidation of mechanisms underlying normal development, as well as embryonic disease and death.

Impact of early changes in left ventricular filling pattern on long-term outcome after acute myocardial infarction

BACKGROUND

In patients with heart failure due to chronic ischemic heart disease improvement of diastolic function indicates improved survival and a reduced morbidity, but whether this is also the case after acute myocardial infarction is not known.

METHODS

To assess the prognostic importance of changes in left ventricular filling pattern, assessed with mitral deceleration time and colour M-mode flow propagation velocity, on cardiac death and readmission due to heart failure serial Doppler echocardiography was carried out in 103 patients with a first myocardial infarction. Based on echocardiography on hospital admission and after 1 month, patients were divided into three groups: group A (n=29) comprised patients with normal filling at either examination, group B (n=29) comprised patients with improvement of initially abnormal filling, and group C (n=45) patients with deterioration or no change of an abnormal filling pattern.

RESULTS

One-year survival free of cardiac death or hospitalisation for heart failure was 97% in group A, 86% in group B and 64% in group C (P<0.0001). In Cox analysis persistence of abnormal filling or deterioration of left ventricular filling was still a predictor of the combined endpoint (risk ratio 4.4, 95% CI 1.8-12.0, P=0.003) after adjustment of LV filling on admission, left ventricular systolic function and clinical variables. Serial analyses of left ventricular systolic function demonstrated a significant improvement after 1 year in ejection fraction in groups A and B, whereas ejection fraction remained unchanged in group C.

CONCLUSION

Patients with a persistently abnormal or a deterioration of left ventricular filling pattern as opposed to improved or normal filling are at increased risk of cardiac death and readmission due to heart failure after acute myocardial infarction.

Left atrial volume: a powerful predictor of survival after acute myocardial infarction

BACKGROUND

After acute myocardial infarction (AMI), diastolic function assessed by Doppler echocardiography provides important prognostic information that is incremental to systolic function. However, Doppler variables are affected by multiple factors and may change rapidly. In contrast, left atrial (LA) volume is less influenced by acute changes and reflects subacute or chronic diastolic function. This may be of importance when one assesses risk in patients with AMI.

METHODS AND RESULTS

Three hundred fourteen patients with AMI who had a transthoracic echocardiogram with assessment of left ventricular (LV) systolic and diastolic function and measurement of LA volume during admission were identified. The LA volume was corrected for body surface area, and the population was divided according to LA volume index of 32 mL/m2 (2 SDs above normal). LA volume index was >32 mL/m2 in 142 (45%). The primary study end point was all-cause mortality. During follow-up of 15 (range 0 to 33) months, 46 patients (15%) died. LA volume index was a powerful predictor of mortality and remained an independent predictor (hazard ratio 1.05 per 1-mL/m2 change, 95% CI 1.03 to 1.06, P<0.001) after adjustment for clinical factors, LV systolic function, and Doppler-derived parameters of diastolic function.

CONCLUSIONS

Increased LA volume index is a powerful predictor of mortality after AMI and provides prognostic information incremental to clinical data and conventional measures of LV systolic and diastolic function.

Ambulatory blood pressure and left ventricular structure and function in relation to the G-protein beta3-subunit polymorphism C825T in White Europeans

The 825T allele of the G-protein beta(3)-subunit is associated with increased intracellular signalling. Its association with hypertension is inconsistent. We, therefore, studied the C825T polymorphism in relation to ambulatory blood pressure as well as left ventricular structure and function in two European populations. We genotyped 248 parents and 318 offspring, enrolled in the European Project on Genes in Hypertension in Cracow, Poland (n=286) and in Novosibirsk, Russian Federation (n=280). The 24-h ambulatory blood pressure was recorded using oscillometric SpaceLabs 90207 monitors. Within each centre, a single observer performed two-dimensionally guided M-mode echocardiography and Doppler sonography to measure left ventricular structure (American Society of Echocardiography conventions) and diastolic function: early (E) and late (A) peak diastolic inflow velocities. We used analysis of covariance and generalized estimating equations to allow for covariables and nonindependence among related subjects. Genotype frequencies were similar (P=0.25) in Cracow and Novosibirsk and amounted to 44.7% for CC, 47.2% for CT, and 8.1% for TT. Among parents (mean age: 51.3 years)-but not among offspring (mean age 25.1 years)-24-h, daytime and night time systolic blood pressures were 5-6 mmHg higher in TT homozygotes than in C allele carriers. In TT homozygous parents (-8.2 cm/sec, P=0.004) as well as in TT homozygous offspring (-7.5 cm/sec, P=0.02), the E-wave was significantly reduced, which in offspring also resulted in a lower E/A ratio (-0.25, P=0.002). Neither in parents nor in offspring, left ventricular mass index was associated with the C825T polymorphism. In conclusion, in TT homozygotes of both generations, early left ventricular relaxation was reduced. In TT homozygous parents, the latter observation might be because of the higher systolic pressure associated with the TT genotype.

Nineteen-millimeter prosthetic aortic valves allow normalization of left ventricular mass in elderly women

BACKGROUND

Implantation of small aortic valve prostheses has been reported to be associated with impaired left ventricular (LV) mass regression and incomplete resolution of symptoms although these data have been generated largely with male patients. Therefore we sought to determine the clinical and hemodynamic outcomes of female patients who received a 19-mm aortic valve.

METHODS

Between May 1995 and December 2000, 38 female patients (average age 73 years, range 42 to 89) underwent isolated aortic valve replacement (AVR; n = 22) or AVR plus coronary artery bypass graft surgery (CABG; n = 16) with a 19-mm aortic prosthesis. The average New York Heart Association (NYHA) class was 3.08 and of the 26 patients who had angina, 47.2% were in CCS class III or IV. Clinical and echocardiographic follow-up was done an average of 33.4 months (8 to 72) after surgery.

RESULTS

Operative mortality was 10.5%. Overall survival at an average of 33 months was 71.1%. The average NYHA class was 1.52 +/- 0.34 postoperatively (p < 0.001 versus preoperative) and 95% had no anginal symptoms or were in Canadian Cardiovascular Society class I. The LV mass index showed significant regression (114 +/- 11 g/m2 to 89 +/- 9 g/m2, p = 0.001) despite an effective orifice area index (EOAI) of 0.64 +/- 0.09 cm2/m2.

CONCLUSIONS

Despite a very small EOAI, elderly female patients with 19-mm prosthetic aortic valves can experience a satisfactory improvement in symptoms and normalization of LV mass. This finding suggests that small prosthetic aortic valves continue to have an application in contemporary cardiac surgical practice. The current perception of patient-prosthesis mismatch may need to be reconsidered for select populations.

Coronary flow reserve and myocardial diastolic dysfunction in arterial hypertension

The aim of this study was to assess the relation between coronary blood flow and left ventricular (LV) myocardial diastolic dysfunction in arterial hypertension. The study population included 30 hypertensive patients who were free of coronary artery disease and pharmacologic therapies. They underwent standard Doppler echocardiography and color tissue Doppler of the middle posterior septum at baseline and with high-dose dobutamine, and second-harmonic Doppler flow analysis of the distal left anterior descending coronary artery at baseline and after vasodilation by dipyridamole (0.56 mg/kg IV in 4'). Coronary flow reserve (CFR) was estimated as the ratio of hyperemic and baseline diastolic flow velocities. According to CFR, hypertensives were divided into 2 groups: 15 patients with normal CFR (>/=2) and 15 patients with reduced CFR (<2). The 2 groups were comparable for sex, age, body mass index, baseline heart rate, and blood pressure. LV mass index was greater in hypertensives with reduced CFR (p <0.01). By color tissue Doppler, baseline and high-dose dobutamine septal systolic velocities did not differ between the 2 groups. The ratio between myocardial velocities in early diastole and at atrial contraction (E(m)/A(m) ratio) was lower in patients with reduced CFR, both at baseline (p <0.05) and with high-dose dobutamine (p <0.00001). After adjusting for age, body mass index, LV mass index, and both high-dose dobutamine diastolic blood rate and heart rate by a multiple linear regression analysis, E(m)/A(m) ratio at high-dose dobutamine was independently associated with CFR in the overall population (beta 0.62, p <0.0005) (cumulative R(2) 0.38, p <0.0005). In conclusion, this study provides evidence of an independent association between CFR and myocardial diastolic function. In hypertensive patients without coronary artery stenosis, CFR alteration may be a determinant of myocardial diastolic dysfunction or diastolic impairment that should be taken into account as possibly contributing to coronary flow reduction.