Kathy Edelman

Effects of aging on left atrial reservoir, conduit, and booster pump function: a multi-institution acoustic quantification study

OBJECTIVE To assess the feasibility of measuring left atrial (LA) function with acoustic quantification (AQ) and then assess the effects of age and sex on LA reservoir, conduit, and booster pump function. PATIENTS AND SETTING 165 subjects without cardiovascular disease, 3–79 years old, were enrolled by six tertiary hospital centres. INTERVENTIONS Continuous LA AQ area data were acquired and signal averaged to form composite waveforms which were analysed off-line. MAIN OUTCOME MEASURES Parameters of LA performance according to age and sex. RESULTS Signal averaged LA waveforms were sufficiently stable and detailed to allow automated analysis in all cases. An age related increase in LA area was noted. LA reservoir function did not vary with age or sex. All parameters of LA passive and active emptying revealed a significant age dependency. Overall, the passive emptying phase accounted for 66% of total LA emptying ranging from 76% in the youngest to 44% in the oldest decade. LA contraction accounted for 34% of atrial emptying in all subjects combined with the older subjects being more dependent on atrial booster pump function. When adjusted for atrial size, there were no sex related differences in LA function. CONCLUSIONS LA reservoir, conduit, and booster pump function can be assessed with automated analysis of signal averaged LA area waveforms. As LA performance varies with age, establishment of normal values should enhance the evaluation of pathologic states in which LA function is important.

Tricuspid Annular Systolic Velocity: A Useful Measurement in Determining Right Ventricular Systolic Function Regardless of Pulmonary Artery Pressures

Assessment of right ventricular (RV) systolic function can be somewhat difficult, particularly in pulmonary hypertension (PH). RV fractional area change (FAC) and tricuspid valve annular motion (TAPSE) although useful in the assessment of RV performance, their use can be sometimes limited and tedious. Thus, a quicker but yet reliable alternative is needed. Accordingly, we compared peak tricuspid annulus systolic (TA Sa) velocities derived from Doppler tissue imaging (DTI) with both RVFAC and TAPSE to estimate RV function in 52 patients (53 ± 16 years) with varying degrees of PH. In this group, mean was RVFAC 49 ± 20, TAPSE was 2.3 ± 0.7 cm, peak TA Sa velocity by DTI was 10.4 ± 3.8 cm/s, left ventricular systolic function was 57 ± 18%, and pulmonary artery systolic pressure was 47 ± 28 mmHg. An excellent correlation was noted between TAPSE and RVFAC (r = 0.91, P < 0.001). Similar correlations were noted between peak TA Sa velocity and RVFAC (r = 0.84, P < 0.001) and between peak TA Sa velocity and TAPSE (r = 0.90, P < 0.001). A TA Sa >10.5 cm/s identified individuals with both a normal RV function and without significant PH. Therefore, we conclude that TA Sa velocity, an easily obtainable DTI measure, that has an excellent correlation with more time‐consuming methods to assess RV systolic function regardless of the degree of PH should be routinely assessed during the initial evaluation and eventual follow‐up of patients either at risk or with documented PH.

Right ventricular dyssynchrony in patients with pulmonary hypertension is associated with disease severity and functional class

BackgroundAbnormalities in right ventricular function are known to occur in patients with pulmonary arterial hypertension.ObjectiveTest the hypothesis that chronic elevation in pulmonary artery systolic pressure delays mechanical activation of the right ventricle, termed dyssynchrony, and is associated with both symptoms and right ventricular dysfunction.MethodsFifty-two patients (mean age 46 ± 15 years, 24 patients with chronic pulmonary hypertension) were prospectively evaluated using several echocardiographic parameters to assess right ventricular size and function. In addition, tissue Doppler imaging was also obtained to assess longitudinal strain of the right ventricular wall, interventricular septum, and lateral wall of the left ventricle and examined with regards to right ventricular size and function as well as clinical variables.ResultsIn this study, patients with chronic pulmonary hypertension had statistically different right ventricular fractional area change (35 ± 13 percent), right ventricular end-systolic area (21 ± 10 cm2), right ventricular Myocardial Performance Index (0.72 ± 0.34), and Eccentricity Index (1.34 ± 0.37) than individuals without pulmonary hypertension (51 ± 5 percent, 9 ± 2 cm2, 0.27 ± 0.09, and 0.97 ± 0.06, p < 0.005, respectively). Furthermore, peak longitudinal right ventricular wall strain in chronic pulmonary hypertension was also different -20.8 ± 9.0 percent versus -28.0 ± 4.1 percent, p < 0.01). Right ventricular dyssynchrony correlated very well with right ventricular end-systolic area (r = 0.79, p < 0.001) and Eccentricity Index (r = 0.83, p < 0.001). Furthermore, right ventricular dyssynchrony correlates with pulmonary hypertension severity index (p < 0.0001), World Health Organization class (p < 0.0001), and number of hospitalizations (p < 0.0001).ConclusionLower peak longitudinal right ventricular wall strain and significantly delayed time-to-peak strain values, consistent with right ventricular dyssynchrony, were found in a small heterogeneous group of patients with chronic pulmonary hypertension when compared to individuals without pulmonary hypertension. Furthermore, right ventricular dyssynchrony was associated with disease severity and compromised functional class.

Noninvasive Estimation of Pulmonary Vascular Resistance in Pulmonary Hypertension

Background: Determination of pulmonary vascular resistance (PVR) in patients with suspected or known pulmonary hypertension (PH) requires right heart catheterization. Our purpose was to use Doppler echocardiography to estimate PVR in patients with PH. Methods: Patient population consisted of 52 patients (53 ± 12 years; 35 females) who underwent Doppler echocardiography and right heart catheterization within 24 hours of each other. The ratio of peak tricuspid regurgitation velocity (TRV) and right ventricular outflow time‐velocity integral (VTIRVOT) was measured via transthoracic echocardiography and correlated to invasively determined PVR. A linear regression equation was generated to determine PVR by echocardiography based upon the TRV/VTIRVOT ratio. PVR by echocardiography was compared to invasive PVR using Bland‐Altman analysis. Results: Significant correlation was demonstrated between TRV/VTIRVOT and PVR by catheterization (r = 0.73; P < 0.001). However, Bland‐Altman analysis showed that agreement between PVR determined by echocardiography and invasive PVR was poor (bias = 0; standard deviation = 4.3 Wood units). In a subset of patients with invasive PVR < 8 Wood units (26 patients), correlation between TRV/VTIRVOT and invasive PVR was strong (r = 0.94; P < 0.001). In these patients, agreement between PVR by echocardiography and invasive PVR was satisfactory (bias = 0; standard deviation = 0.5 Wood units). There was no correlation between TRV/VTIRVOT and invasive PVR in patients with PVR > 8 Wood units (n = 26; r = 0.17). Conclusion: While TRV/VTIRVOT correlates significantly with PVR, using it to estimate PVR in a PH patient population cannot be recommended.

Right Ventricular Apical Contractility in Acute Pulmonary Embolism: The McConnell Sign Revisited

Background: The McConnell sign has been regarded as a highly specific echo finding in acute pulmonary embolism (aPE). However, a completely satisfying explanation to account for this observation in aPE remains elusive. We used longitudinal velocity vector imaging (VVI) using a dedicated software program (Research Arena, Siemens, California) to assess regional right ventricular global and apical (RVa) mechanics between aPE and chronic pulmonary hypertension (cPH) patients. Methods: Standard echo parameters of RV performance as well as base to apex RV strain and dyssynchrony were quantified using VVI in a total of 30 patients. The population studied was divided into three groups: Group I included 10 healthy volunteers (50 ± 16 years), Group II consisted of 10 patients (47 ± 13 years) with known cPH, and Group III comprised 10 patients (58 ± 18 years; P = 0.323) with documented aPE. Results: Progressively lower indices of RV performance as well as RV basal and apical strain were recorded in Groups II and III, respectively. Most importantly, no difference in RVa segmental strain values was seen between Groups II and III. Conclusions: Based on this pilot data, aPE patients demonstrate a significant reduction in overall RV strain with a similar reduction in RV apical deformation. Therefore, regional RVa function is not truly spared in aPE and the probable visual illusion of preserved contractility might simply reflect tethering of the RVa to a hyperdynamic left ventricle in the presence of an acutely dilated RV. (Echocardiography 2010;27:614‐620)

An Abnormal Right Ventricular Apical Angle is Indicative of Global Right Ventricular Impairment

The presence of right ventricular (RV) dysfunction is an adverse prognostic indicator but current echocardiographic methods have some limitations. RV apical angles in systole and diastole were correlated with known parameters of RV function in patients without pulmonary hypertension (Group 1) and in patients with pulmonary hypertension (Group 2). RV apical angles were significantly smaller in both systole (22 ± 7°) and diastole (33 ± 6°) in Group 1 patients when compared to Group 2 (54 ± 18°, p < 0.0001 and 59 ± 17°, p < 0.0001, respectively). RV apical angles, both in systole and diastole, were strongly correlated with RV end‐systolic area (R = 0.89, p < 0.0001) and end‐diastolic area (R = 0.81, p < 0.0001), respectively. Similarly, the apical systolic and diastolic angle correlated well with decreased tricuspid annular plane systolic excursion (TAPSE, R =−0.76 and R =−0.73, p < 0.001) as well as with decreased RV fractional area change (R =−0.81 and R =−0.77, p < 0.001). Therefore, we conclude that this new measurement of RV apical angle is simple and useful to quantify RV apical structural and functional abnormalities that are well correlated with global RV impairment in patients with chronic pulmonary hypertension.

Evidence of robust coupling of atrioventricular mechanical function of the right side of the heart: insights from M-mode analysis of annular motion.

Background: Extensive data exist regarding annular descent and ventricular function. We have already demonstrated significant differences in amplitude and timing of events between maximal mitral (MAPSE) and tricuspid (TAPSE) annular plane systolic excursion as well as described quantitative temporal differences in annular ascent (AA) between the right and left sides of the heart. However, whether any relationship exists between annular ascent and descent components remains uninvestigated. Methods: Left ventricular ejection fraction (LVEF), right ventricular fractional area change (RVFAC), MAPSE, TAPSE, MV, and TV AA as well as pulsed tissue Doppler of the lateral MV and TV annuli were recorded from 53 patients. Results: In this population (age 55 ± 17 years) mean LVEF was 55 ± 19%, mean RVFAC was 47 ± 20%, mean MAPSE was 2.11 ± 0.72 cm, mean TAPSE was 1.48 ± 0.44 cm, mean MV AA was 0.52 ± 0.17 cm, TV AA was 0.96 ± 0.47, MV A‐wave 0.10 ± 0.04 cm/s, and TV A‐wave was 0.13 ± 0.05 cm/s. A more robust correlation was seen between TV AA and RVFAC than between MV AA and LVEF and also between TV AA and pulsed TDI TV A‐wave velocity than between MV AA and pulsed TDI MV A‐wave. Conclusion: Our data reveal that mechanical systolic functions of the atria and the ventricles are more closely coupled on the right than on the left side of the heart. Whether this is a result of anatomic linking or chamber geometry will require further study.

Abnormal Right Ventricular Myocardial Strain Generation in Mild Pulmonary Hypertension

Background: Although right ventricular (RV) dyssynchrony has been identified in patients with severe pulmonary hypertension due to significant RV enlargement and compromise in systolic function, a more clinically relevant question pertains to RV mechanical properties in patients with mild elevation in pulmonary artery systolic pressures (PASP). Methods: Several echocardiographic parameters and peak longitudinal strain were measured in 40 patients and divided into two groups of 20 patients based on their PASP. Results: Group I included 20 individuals (mean age 48 ± 16 years with a mean PASP of 27 ± 5 mmHg) and Group II included 20 patients (mean age 63 ± 14 years with a mean PASP of 49 ± 7 mmHg.) All time intervals were adjusted for heart rate. RV fractional area change and tricuspid annular plane systolic excursion for Group I (62 ± 12% and 2.74 ± 0.56 cm) and Group II (49 ± 14%; P < 0.02 and 2.09 ± 0.40; P < 0.002) were both normal. However, Group II had lower peak longitudinal RV free wall (RVF) strain (−27.3 ± 7.1 % vs. −31.9 ± 8.7%, P < 0.04), longer time to peak RVF strain (448 ± 57 ms vs. 411 ± 43 ms; P < 0.03) and evidence of significant RV dyssynchrony (−83 ± 55 ms vs. 1 ± 17 ms, P < 0.00001) in contrast to Group I. Conclusion: In conclusion, mild elevations in PASP affect the mechanical properties of the RV and result in RV dyssynchrony despite absence of gross abnormalities in RV size or function.

Comparative echocardiographic analysis of mitral and tricuspid annular motion: differences explained with proposed anatomic-structural correlates.

Background: Annular motion (AM) has been shown to occur during all dynamic phases of the cardiac cycle; but little is known regarding comparisons between mitral and tricuspid AM. We elected to use M‐mode to examine the extent and timing of mitral and tricuspid AM events. Methods: A complete echocardiogram was obtained in 50 patients [mean age 53 ± 16 years, mean left ventricular ejection fraction (LVEF) 57 ± 19%, and mean right ventricular fractional area change (RVFAC) of 49 ± 20%]. Timing of all AM intervals was corrected for heart rate. Results: A strong linear correlation was noted for both LVEF and maximal mitral annular systolic excursion and for RVFAC and maximal tricuspid annular systolic excursion (r = 0.91, P < 0.0001). The amplitude of both maximal mitral annular descent (1.54 ± 0.45 cm) and ascent (0.64 ± 0.23 cm) was significantly smaller than for the tricuspid annulus (2.26 ± 0.73 and 0.98 ± 0.37 cm; P < 0.0001, respectively). Furthermore, while it takes longer for the mitral than for the tricuspid annulus (403 ± 52 ms vs 308 ± 50 ms; P < 0.0001, respectively) to descend to its lowest point; the duration to reach maximal ascent is shorter for the mitral than for tricuspid annulus (90 ± 22 ms vs 115 ± 19 ms; p < 0.0001, respectively). Conclusion: Significant differences exist in both amplitude and timing of AM events between the mitral and tricuspid annuli, likely reflecting intrinsic anatomical and electromechanical differences between both sides of the heart that require further investigation.

Apical Systolic Eccentricity Index: A Better Marker of Right Ventricular Compromise in Pulmonary Hypertension

Background: Systolic eccentricity index (sEI) has been traditionally measured at the papillary muscle (PM) level. However, this measurement does not take into account the remodeling that occurs in the right ventricle (RV) during chronic pulmonary hypertension (cPH). Methods: Standard echocardiographic data were collected on 50 patients (age 58 ± 14 years) with known cPH (74 ± 22 mmHg; range 45–120 mmHg) who had adequate short‐axis views at the mitral valve (MV), PM, and apical (AP) levels to measure sEI. All had a normal left ventricular ejection fraction (72 ± 10%). Results: In a multivariate analysis, the traditional PM level sEI correlated the best with cPH when pulmonary artery systolic pressures (PASP) ranged between 45 and 60 mmHg (r =−0.569, P < 0.001) while AP level sEI was better when all patients were included in the analysis (r =−0.843, P < 0.0001). Not only was AP level sEI the only echo variable helpful in identifying a dilated end diastolic RV area (r =−0.730, P < 0.0001) but also patients with worse RV systolic performance (r = 0.686, P < 0.0001). MV level sEI was not better than PM level sEI. Conclusions: AP level sEI appears to be superior to traditional PM level sEI measurement as it correlates better with worsening PH severity, RV cavity dilation and RV systolic dysfunction. Further studies are now required to prospectively study how these septal abnormalities in cPH may affect RV as well as LV systolic and diastolic function. (Echocardiography 2010;27:534‐538)