Mitral annular velocity may be measured angle independently by speckle tracking echocardiography (STE), in contrast with tissue Doppler imaging (TDI). The purpose of the current study was to compare ...STE and TDI, with respect to 1) the accuracy of velocity measurements in a moving phantom, 2) the feasibility and reproducibility of measurement of mitral annular velocities in a clinical setting, and 3) the estimation of left ventricular filling pressures using mitral annular velocities.
The velocity of a moving phantom, using different angles of insonation, and mitral annular velocities of 80 nonselected patients and 50 healthy volunteers were determined using TDI and STE. A subgroup of 20 patients was studied during right-sided heart catheterization.
When the motion direction of the phantom was parallel to the ultrasound beam, both TDI and STE determined velocities accurately. With increasing angle of insonation, TDI-derived velocity decreased, whereas STE-derived velocity remained unchanged. The feasibility of mitral annular velocities measured by TDI and STE was comparable (98% vs 95%, P = not significant). Although for both techniques correlations between measured mitral annular velocities at repeated examinations were good, the test-retest variability of mitral annular velocities by TDI was higher. E/Em ratio by STE correlated better to pulmonary capillary wedge pressure (R(2) = 0.51, P < .001) compared with E/Em ratio derived from TDI (R(2) = 0.35, P < .01), although the difference in correlation was not statistically significant because of the limited sample size.
Tissue velocities can be accurately determined by STE in a moving phantom and are angle independent, in contrast with TDI measurements. Furthermore, STE is a feasible and better reproducible method for the assessment of mitral annular velocities in a clinical setting.
Background: In order to gain further insight into age-associated changes of left ventricular (LV) diastolic function, the purpose of the current study was to investigate alterations in LV untwisting ...with ageing. Methods and Results: The study comprised 75 healthy volunteers, classified into 3 groups: age 16-35 (n=25), 36-55 (n=25) and 56-75 (n=25) years. LV untwisting (as a percentage of peak systolic twist) at 5%, 10%, 15% and 50% of diastole, peak diastolic untwisting velocity, time-to-peak diastolic untwisting velocity and untwisting rate (mean untwisting velocity during the time interval from peak systolic twist to mitral valve opening) were assessed using speckle-tracking echocardiography. Untwisting at 5%, 10%, 15% and 50% of diastole decreased with ageing. Although the peak diastolic untwisting velocity and untwisting rate were not significantly different between the age groups, when normalized for LV peak systolic twist, these parameters decreased with advancing age (both P<0.01). Time-to-peak diastolic untwisting velocity increased with ageing (P<0.01). Conclusions: Impairment of the relative peak diastolic untwisting velocity and untwisting rate, resulting in delayed LV untwisting, may help to explain diastolic dysfunction in the elderly. (Circ J 2010; 74: 101 - 108)
Assessment of pulmonary valve (PV) and right ventricular outflow tract (RVOT) using real-time 3-dimensional echocardiography (RT3DE).
Two-dimensional echocardiography (2DE) and RT3DE were performed ...in 50 patients with congenital heart disease (mean age 32 +/- 9.5 years, 60% female). Measurements were obtained at parasternal views: short axis (PSAX) at aortic valve level and long axis (PLAX) with superior tilting. RT3DE visualization was evaluated by 4-point score (1: not visualized, 2: inadequate, 3: sufficient, and 4: excellent). Diameters of PV annulus (PVAD), and RVOT (RVOTD) were measured by both 2DE and RT3DE, while areas (PVAA) and (RVOTA) by RT3DE only.
By RT3DE, PV was visualized sufficiently in 68% and RVOT excellently in 40%. PVAD and PVAA were measured in 88%. RVOTD and PVAD by 2DE at PLAX were significantly higher than PSAX (P < 0.0001) and lower than that by RT3DE (P < 0.001).
RT3DE helps in RVOT and PV assessment adding more details supplemental to 2DE.
The aim of the present study was to determine the long-term effects of percutaneous transluminal septal myocardial ablation (PTSMA) on systolic and diastolic left ventricular (LV) functions in ...patients with obstructive hypertrophic cardiomyopathy (HC). Ten consecutive patients with symptomatic HC despite optimal medical treatment were referred for PTSMA at our center. LV systolic and diastolic functions were assessed by online LV pressure–volume loops obtained by conductance catheter at baseline and at 6 months after the procedure. At follow-up, the mean gradients at rest and after extrasystole were significantly decreased compared with baseline (88 ± 29 to 21 ± 11 mm Hg and 130 ± 50 to 35 ± 22 mm Hg, respectively, p <0.01 for the 2 comparisons). End-systolic and end-diastolic pressures significantly decreased (p <0.01), whereas end-systolic and end-diastolic LV volumes significantly increased (p <0.01 for the 2 comparisons). Cardiac output and stroke volume were unchanged, as were ejection fraction (p = 0.25) and maximum dP/dt (p = 0.13). The slope of the end-systolic pressure–volume relation was not decreased, indicating a preserved contractility. The relaxation constant time, end-diastolic stiffness, projected volume of the end-diastolic pressure–volume relation at 30 mm Hg, and diastolic stiffness constant showed a significant improvement of active and passive myocardial diastolic properties. In conclusion, PTSMA is an effective method in the treatment of symptomatic patients with HC. At 6-month follow-up, the LV–aortic gradient was decreased and active and passive LV diastolic properties were increased. Myocardial contractility was not decreased and general hemodynamics was maintained.
Clinical characteristics of patients, angiographic referral bias, and several technical factors may all affect the reported diagnostic accuracy of tests. The aim of this study was to assess their ...influence on the diagnostic accuracy of dobutamine stress echocardiography (DSE).
The medical literature from 1991 to 2006 was searched for diagnostic studies using DSE and meta-analysis was applied to the 62 studies thus retrieved, including 6881 patients. These studies were analyzed for patient characteristics, angiographic referral bias, and several technical factors.
The sensitivity of DSE was significantly related to the inclusion of patients with prior myocardial infarctions (0.834 vs 0.740, P < .01) and defining the results of DSE as already positive in case of resting wall motion abnormalities rather than obligatory myocardial ischemia (0.786 vs 0.864, P < .01). Specificity tended to be lower when patients with resting wall motion abnormalities were included in a study (0.812 vs 0.877, P < .10). The presence of referral bias adversely affected the specificity of DSE (0.771 vs 0.842, P < .01).
This analysis suggests that the reported sensitivity of DSE is likely higher and the specificity lower than expected in routine clinical practice because of the inappropriate inclusion of patients with prior myocardial infarctions, the definition of positive results on DSE, and the negative influence of referral bias. However, in the patient subset that will be sent to coronary angiography, the opposite results can be expected.
This study investigated the effects of alcohol septal ablation (ASA) on microcirculatory function and myocardial energetics in patients with hypertrophic cardiomyopathy (HCM) and left ventricular ...outflow tract (LVOT) obstruction. In 15 HCM patients who underwent ASA, echocardiography was performed before and 6 mo after the procedure to assess the LVOT gradient (LVOTG). Additionally, (15)Owater PET was performed to obtain resting myocardial blood flow (MBF) and coronary vasodilator reserve (CVR). Changes in LV mass (LVM) and volumes were assessed by cardiovascular magnetic resonance imaging. Myocardial oxygen consumption (MVo(2)) was evaluated by (11)Cacetate PET in a subset of seven patients to calculate myocardial external efficiency (MEE). After ASA, peak LVOTG decreased from 41 ± 32 to 23 ± 19 mmHg (P = 0.04), as well as LVM (215 ± 74 to 169 ± 63 g; P < 0.001). MBF remained unchanged (0.94 ± 0.23 to 0.98 ± 0.15 ml·min(-1)·g(-1); P = 0.45), whereas CVR increased (2.55 ± 1.23 to 3.05 ± 1.24; P = 0.05). Preoperatively, the endo-to-epicardial MBF ratio was lower during hyperemia compared with rest (0.80 ± 0.18 vs. 1.18 ± 0.15; P < 0.001). After ASA, the endo-to-epicardial hyperemic (h)MBF ratio increased to 1.03 ± 0.26 (P = 0.02). ΔCVR was correlated to ΔLVOTG (r = -0.82; P < 0.001) and ΔLVM (r = -0.54; P = 0.04). MEE increased from 15 ± 6 to 20 ± 9% (P = 0.04). Coronary microvascular dysfunction in obstructive HCM is at least in part reversible by relief of LVOT obstruction. After ASA, hMBF and CVR increased predominantly in the subendocardium. The improvement in CVR was closely correlated to the absolute reduction in peak LVOTG, suggesting a pronounced effect of LV loading conditions on microvascular function of the subendocardium. Furthermore, ASA has favorable effects on myocardial energetics.
Cardiac data in adults with mitochondrial encephalomyopathy, lactic acidosis, and strokelike episodes (MELAS syndrome) or asymptomatic gene carriers with the mitochondrial deoxyribonucleic acid ...adenine-to-guanine point mutation at nucleotide pair 3243 are scarce. Twelve subjects (mean age 35 ± 13 years), 8 with MELAS syndrome (patients) and 4 asymptomatic gene carriers (carriers), were enrolled in the study. Each subject underwent electrocardiography, exercise testing, Holter monitoring, echocardiography, and genetic and biochemical analysis for respiratory chain enzyme activity (complex I rest activity) in skeletal muscle. On electrocardiography and Holter monitoring, none of the subjects had evidence of preexcitation, cardiac arrhythmias, or conduction abnormalities. Patients had significantly lower (42 ± 17% from normal vs 103 ± 14%, p <0.02) exercise tolerance. All but 1 of the patients and none of the gene carriers had ragged red fibers on muscle biopsy. The mean percentage of gene mutation in skeletal muscle tended to be higher in patients (53 ± 19%, range 19% to 73%) compared with carriers (33 ± 20%, range 15% to 62%). Mean complex I rest activity in patients (36 ± 18%, range 10% to 58%) was significantly (p <0.01) lower compared with carriers (120 ± 60%, range 72% to 205%). Left ventricular (LV) abnormalities were confined to patients with MELAS syndrome. Two patients had LV hypertrophy, 5 had LV systolic abnormalities, and 5 had LV diastolic dysfunction. Apart from 1 patient with an isolated LV diastolic abnormality, all patients with LV abnormalities had ragged red fibers. Patients with abnormal systolic LV function had a trend toward a higher percentage of mutated skeletal muscle (59.7 ± 10.7% vs 35.8 ± 21.3%, p <0.10) and significantly lower complex I rest activity (26.7 ± 14.0% vs 97.8% ± 57.9, p <0.01). In conclusion, none of the MELAS gene carriers had cardiac abnormalities, whereas most patients with the MELAS phenotype, particularly those with ragged red fibers, had LV involvement.
To assess real-time 3-dimensional echocardiography (RT3DE)-derived left ventricular (LV) systolic dyssynchrony parameters: (1) normal values, (2) characteristics in patients with heart failure (HF) ...and a wide or narrow QRS complex, (3) interobserver and intraobserver variability with current state of the art RT3DE hardware and software technology, and (4) incremental value in patients with HF who receive cardiac resynchronization therapy (CRT).
The study involved 84 patients with HF (mean age 54 +/- 15 years, 50 men) and 60 healthy volunteers (mean age 41 +/- 15 years, 36 men). Semiautomated LV endocardial border tracking was used to calculate regional time-to-minimum systolic volume and to generate parametric maps and the systolic dyssynchrony index (SDI), defined as the standard deviation of time-to-minimum systolic volume of the 16 LV segments expressed in percentage of R-R duration.
The volume rate of the RT3DE datasets in patients with HF was 31 +/- 9 Hz (range 15-42 Hz). The normal value of the SDI was 4.1% +/- 2.2% (range <1.0%-8.9%). Patients with HF had a larger SDI (13.4% +/- 8.1%, P < .001). There was only a weak correlation (r2 = 0.07, P < .05) between the QRS duration and the SDI. Interobserver interclass correlation and variability of the SDI depended on image quality (good: 0.993 and 9%, moderate: 0.907 and 16%, respectively). Interobserver agreement for the identification of the most delayed LV segment depended on image quality (good: 90%, moderate: 76%). Thirty-nine patients underwent CRT. At the 12-month follow-up, LV volumetric responders had a significant reduction in the SDI (16.3% +/- 3.3% to 7.7% +/- 2.4%, P < .001).
With state of the art technology, RT3DE allows reproducible assessment of LV systolic dyssynchrony, which may be useful to identify potential responders to CRT.
a Thoraxcenter, Room Ba 302, Erasmus MC, Dr. Molewaterplein 40, 3015 GD Rotterdam, The Netherlands
b Cardiology Department, Al-Husein University Hospital, Al-Azhar University, Cairo, Egypt
...*Corresponding author. Tel.: +31-10-4633986; fax: +31-10-4635498. E-mail address : f.j.meijboom{at}erasmusmc.nl (F.J. Meijboom).
Tricuspid annulus (TA) evaluation continues to be a major problem in the surgical decision-making process. Obviously, 2-dimensional transthoracic echocardiography (2D TTE) is limited in TA visualization due to its complex 3D shape. The study aimed to determine TA morphology, size and function with real-time three-dimensional echocardiography (RT3DE) in 40 patients divided into two equal groups (I: normal TA and II: dilated). 2D TTE measurements included TA diameter (TAD) at apical 4-chamber (AP4CH) and parasternal short axis (PSAX) views. RT3DE measurements included TA area (TAA), major TAD and minor TAD. TA fractional shortening (TAFS), and TA fractional area change (TAFAC) were calculated from end-systolic and end-diastolic measurements. RT3DE allowed visualization and measurement of the entire oval-shaped TA in all patients irrespective of its size (normal or dilated). 2D TTE measurement of TAD at both AP4CH and at PSAX views was significantly smaller than the major TAD measured by RT3DE ( P <0.0001) and nearly matched with the minor TAD in all patients. Calculation of TAFS was comparable with both techniques. TAFAC was significantly higher than TAFS ( P <0.0001). So, RT3DE could be relied on more accurately than 2D TTE in the assessment of TA size and function which may aid in decision-making and selection of proper surgical procedure when indicated.
Key Words: Tricuspid annulus; Real-time 3D echocardiography
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