Sherif F. Nagueh

Recommendations for the Evaluation of Left Ventricular Diastolic Function by Echocardiography

Recommendations for the evaluation of left ventricular diastolic function by echocardiography

Doppler Tissue Imaging: A Noninvasive Technique for Evaluation of Left Ventricular Relaxation and Estimation of Filling Pressures

OBJECTIVES This investigation was designed 1) to assess whether the early diastolic velocity of the mitral annulus (Ea) obtained with Doppler tissue imaging (DTI) behaves as a preload-independent index of left ventricular (LV) relaxation; and 2) to evaluate the relation of the mitral E/Ea ratio to LV filling pressures. BACKGROUND Recent observations suggest that Ea is an index of LV relaxation that is less influenced by LV filling pressures. METHODS One hundred twenty-five study subjects were classified into three groups according to mitral E/A ratio, LV ejection fraction (LVEF) and clinical symptoms: 34 asymptomatic subjects with a normal LVEF and an E/A ratio > or =1; 40 with a normal LVEF, an E/A ratio <1 and no heart failure symptoms (impaired relaxation [IR]); and 51 with heart failure symptoms and an E/A ratio >1 (pseudonormal [PN]). Ea was derived from the lateral border of the annulus. A subset of 60 patients had invasive measurement of pulmonary capillary wedge pressure (PCWP) simultaneous with Doppler echocardiographic DTI. RESULTS Ea was reduced in the IR and PN groups compared with the group of normal subjects: 5.8 +/- 1.5 and 5.2 +/- 1.4 vs. 12 +/- 2.8 cm/s, respectively (p < 0.001). Mean PCWP (20 +/- 8 mm Hg) related weakly to mitral E (r = 0.68) but not to Ea. The E/Ea ratio related well to PCWP (r = 0.87; PCWP = 1.24 [E/Ea] + 1.9), with a difference between Doppler and catheter measurements of 0.1 +/- 3.8 mm Hg. CONCLUSIONS Ea behaves as a preload-independent index of LV relaxation. Mitral E velocity, corrected for the influence of relaxation (i.e., the E/Ea ratio), relates well to mean PCWP and may be used to estimate LV filling pressures.

Current and evolving echocardiographic techniques for the quantitative evaluation of cardiac mechanics: ASE/EAE consensus statement on methodology and indications: Endorsed by the Japanese Society of Echocardiography

Echocardiographic imaging is ideally suited for the evaluation of cardiac mechanics because of its intrinsically dynamic nature. Because for decades, echocardiography has been the only imaging modality that allows dynamic imaging of the heart, it is only natural that new, increasingly automated techniques for sophisticated analysis of cardiac mechanics have been driven by researchers and manufacturers of ultrasound imaging equipment.Several such technique shave emerged over the past decades to address the issue of readers experience and inter measurement variability in interpretation.Some were widely embraced by echocardiographers around the world and became part of the clinical routine,whereas others remained limited to research and exploration of new clinical applications.Two such techniques have dominated the research arena of echocardiography: (1) Doppler based tissue velocity measurements,frequently referred to as tissue Doppler or myocardial Doppler, and (2) speckle tracking on the basis of displacement measurements.Both types of measurements lend themselves to the derivation of multiple parameters of myocardial function. The goal of this document is to focus on the currently available techniques that allow quantitative assessment of myocardial function via image-based analysis of local myocardial dynamics, including Doppler tissue imaging and speckle-tracking echocardiography, as well as integrated backscatter analysis. This document describes the current and potential clinical applications of these techniques and their strengths and weaknesses,briefly surveys a selection of the relevant published literature while highlighting normal and abnormal findings in the context of different cardiovascular pathologies, and summarizes the unresolved issues, future research priorities, and recommended indications for clinical use.

Doppler Estimation of Left Ventricular Filling Pressure in Sinus Tachycardia A New Application of Tissue Doppler Imaging

BACKGROUND Doppler echocardiography is frequently used to predict filling pressures in normal sinus rhythm, but it is unknown whether it can be applied in sinus tachycardia, with merging of E and A velocities. Tissue Doppler imaging (TDI) can record the mitral annular velocity. The early diastolic velocity (Ea) behaves as a relative load-independent index of left ventricular relaxation, which corrects the influence of relaxation on the transmitral E velocity. METHODS AND RESULTS We evaluated 100 patients 64+/-12 years old with simultaneous Doppler and invasive hemodynamics. Mitral inflow was classified into 3 patterns: complete merging of E and A velocities (pattern A), discernible velocities with A dominance (B), or E dominance (C). The Doppler data were analyzed at the mitral valve tips for E, acceleration and deceleration times of E, and isovolumic relaxation time. In patterns B and C, the A velocity, E/A ratio, and atrial filling fraction were derived. Pulmonary venous flow velocities were also measured, and TDI was used to acquire Ea and Aa. Weak significant relations were observed between pulmonary capillary wedge pressure (PCWP) and sole parameters of mitral flow, pulmonary venous flow, and annular measurements. These were better for patterns A and C. E/Ea ratio had the strongest relation to PCWP [r=0.86, PCWP=1.55+1.47(E/Ea)], irrespective of the pattern and ejection fraction. This equation was tested prospectively in 20 patients with sinus tachycardia. A strong relation was observed between catheter and Doppler PCWP (r=0.91), with a mean difference of 0.4+/-2.8 mm Hg. CONCLUSIONS The ratio of transmitral E velocity to Ea can be used to estimate PCWP with reasonable accuracy in sinus tachycardia, even with complete merging of E and A velocities.

Tissue Doppler Imaging Consistently Detects Myocardial Abnormalities in Patients With Hypertrophic Cardiomyopathy and Provides a Novel Means for an Early Diagnosis Before and Independently of Hypertrophy

Background—Left ventricular hypertrophy (LVH), the clinical hallmark of familial hypertrophic cardiomyopathy (FHCM), is absent in a significant number of subjects with causal mutations. In transgenic rabbits that fully recapitulate the FHCM phenotype, reduced myocardial tissue Doppler (TD) velocities accurately identified the mutant rabbits, even in the absence of LVH. We tested whether humans with FHCM also consistently showed reduced myocardial TD velocities, irrespective of LVH. Methods and Results—We performed 2D and Doppler echocardiography and TD imaging in 30 subjects with FHCM, 13 subjects who were positive for various mutations but did not have LVH, and 30 age- and sex-matched controls (all adults; 77% women). LV wall thickness and mass were significantly greater in FHCM subjects (P <0.01 versus those without LVH and controls). There were no significant differences in 2D echocardiographic, mitral, and pulmonary venous flow indices between mutation-positives without LVH and controls. In contrast, systolic and early diastolic TD velocities were significantly lower in both mutation-positives without LVH and in FHCM patients than in controls (P <0.001). Reduced TD velocities had a sensitivity of 100% and a specificity of 93% for identifying mutation-positives without LVH. Conclusions—Myocardial contraction and relaxation velocities, detected by TD imaging, are reduced in FHCM, including in those without LVH. Before and independently of LVH, TD imaging is an accurate and sensitive method for identifying subjects who are positive for FHCM mutations.

Current and Evolving Echocardiographic Techniques for the Quantitative Evaluation of Cardiac Mechanics: ASE/EAE Consensus Statement on Methodology and Indications Endorsed by the Japanese Society of Echocardiography

Echocardiographic imaging is ideally suited for the evaluation of cardiac mechanics because of its intrinsically dynamic nature. Because for decades, echocardiography has been the only imaging modality that allows dynamic imaging of the heart, it is only natural that new, increasingly automated techniques for sophisticated analysis of cardiac mechanics have been driven by researchers and manufacturers of ultrasound imaging equipment. Several such techniques have emerged over the past decades to address the issue of readers experience and inter-measurement variability in interpretation. Some were widely embraced by echocardiographers around the world and became part of the clinical routine, whereas others remained limited to research and exploration of new clinical applications. Two such techniques have dominated the research arena of echocardiography: (1) Doppler-based tissue velocity measurements, frequently referred to as tissue Doppler or myocardial Doppler, and (2) speckle tracking on the basis of displacement measurements. Both types of measurements lend themselves to the derivation of multiple parameters of myocardial function. The goal of this document is to focus on the currently available techniques that allow quantitative assessment of myocardial function via image-based analysis of local myocardial dynamics, including Doppler tissue imaging and speckle-tracking echocardiography, as well as integrated back- scatter analysis. This document describes the current and potential clinical applications of these techniques and their strengths and weaknesses, briefly surveys a selection of the relevant published literature while highlighting normal and abnormal findings in the context of different cardiovascular pathologies, and summarizes the unresolved issues, future research priorities, and recommended indications for clinical use.

Hemodynamic determinants of the mitral annulus diastolic velocities by tissue Doppler.

OBJECTIVES Our goal was to identify the hemodynamic determinants of the mitral annulus (MA) diastolic velocities by tissue Doppler. BACKGROUND The MA diastolic velocities are promising indexes of left ventricular (LV) diastolic function. However, their hemodynamic determinants have not yet been evaluated. METHODS Ten adult mongrel dogs underwent left atrial (LA) and LV pressure measurements by Millar catheters while tissue Doppler was applied to record the MA diastolic velocities at the septal and lateral comers. Conventional transmitral flow was also obtained. Left atrial and LV pressures were modified utilizing fluid administration and caval occlusion, whereas dobutamine and esmolol were used to change LV and LA relaxation. Left ventricular filling pressures were altered during different lusitropic states to evaluate for the possible interaction of preload and LV relaxation on the early diastolic velocity (Ea). RESULTS In the majority of dogs, a positive significant relation was observed between Ea and the transmitral pressure gradient (r = 0.57, p = 0.04). The Ea had strong correlations with tau (r = -0.83, p < 0.001), LV -dP/dt (r = 0.8, p < 0.001) and minimal LV pressure (r = -0.76, p < 0.01). However, there was no relation between Ea and the transmitral pressure gradient in experimental stages where tau >50 ms. Furthermore, the late diastolic velocity at both corners of the MA had significant positive relations with LA dP/dt (r = 0.67, p < 0.01) and LA relaxation (r = 0.73, p < 0.01) but an inverse correlation with LV end-diastolic pressure (r = -0.53, p = 0.01). CONCLUSIONS Left ventricular relaxation, minimal pressure and preload determine Ea while late diastolic velocity determinants include LA dP/dt, LA relaxation and LV end-diastolic pressure.

Avoiding Papillary Muscle Infarction With Myocardial Contrast Echocardiographic Guidance of Nonsurgical Septal Reduction Therapy for Hypertrophic Obstructive Cardiomyopathy

Intracoronary myocardial contrast echocardiography (MCE) can be used to guide the delivery of ethanol during nonsurgical septal reduction therapy for hypertrophic obstructive cardiomyopathy. The echocardiographic contrast agent is injected immediately before the injection of ethanol, down the lumen of the inflated balloon that resides in the target septal coronary artery. This is the artery that supplies the area of the septum involved with the mitral leaflet(s) in causing dynamic outflow tract obstruction. MCE provides a direct visualization of the myocardial territory that should receive ethanol and consequently undergo infarction. In rare instances, the cannulated vessel does not supply the culprit septal segment(s) but supplies instead …

Doppler Estimation of Left Ventricular Filling Pressures in Patients With Hypertrophic Cardiomyopathy

BACKGROUND Conventional Doppler parameters are unreliable for estimating left ventricular (LV) filling pressures in hypertrophic cardiomyopathy (HCM). This study was undertaken to evaluate flow propagation velocity by color M-mode and early diastolic annular velocity (Ea) by tissue Doppler 2 new indices of LV relaxation, combined with mitral E velocity for estimation of filling pressures in HCM. METHODS AND RESULTS Thirty-five HCM patients (52+/-15 years) underwent LV catheterization simultaneously with 2-dimensional and Doppler echocardiography. Pulsed Doppler echocardiography of mitral and pulmonary venous flows was obtained along with flow propagation velocity and Ea. LV preA pressure had weak or no relations with mitral, pulmonary venous velocities and atrial volumes. In contrast, preA pressure related strongly to E velocity/flow propagation velocity (r=0.67; SEE=4) and E/Ea (r=0.76; SEE=3.4). In 17 patients with repeat measurements, preA pressure changes were well detected by measuring E velocity/flow propagation velocity (r=0.68; P=0.01) or E/Ea (r=0.8; P<0.001). PreA pressure estimation with these 2 methods was tested prospectively in 17 additional HCM patients with good results (E velocity/flow propagation velocity, r=0.76; E/Ea, r=0.82). CONCLUSIONS LV filling pressures can be estimated with reasonable accuracy in HCM patients by measuring E velocity/flow propagation velocity or E/Ea. These ratios also track changes in filling pressures.

Optimal Noninvasive Assessment of Left Ventricular Filling Pressures A Comparison of Tissue Doppler Echocardiography and B-Type Natriuretic Peptide in Patients With Pulmonary Artery Catheters

Background—Early transmitral velocity/tissue Doppler mitral annular early diastolic velocity (E/Ea) and B-type natriuretic peptide (BNP) have been correlated with left ventricular filling pressures, yet there are no data on how these 2 estimates of left ventricular filling pressures compare. Methods and Results—Patients admitted to intensive care underwent simultaneous tissue Doppler echocardiography, BNP measurement, and pulmonary capillary wedge pressure (PCWP) determination. The ability of mitral E/Ea and BNP to predict PCWP >15 mm Hg was assessed. Fifty patients were studied. Ln BNP had a correlation of r = 0.32 (P = 0.02) with PCWP compared with r = 0.69 (P < 0.001) between E/Ea and PCWP. E/Ea >15 was the optimal cutoff to predict PCWP >15 mm Hg (sensitivity, 86%; specificity, 88%), whereas the optimal BNP cutoff was >300 pg/mL (sensitivity, 91%; specificity, 56%). The correlation between change in PCWP and change in E/Ea at 48 hours was r = 0.87 (P = 0.003) compared with r = −0.59 (P = 0.39) for BNP. In the 36 patients with cardiac disease, E/Ea >15 (sensitivity, 92%; specificity, 91%) appeared more accurate than BNP >400 pg/mL (sensitivity, 92%; specificity, 51%), whereas in patients without cardiac disease, BNP (sensitivity, 81%; specificity, 83%) appeared more accurate than E/Ea >15 (sensitivity, 74%; specificity, 72%) for PCWP >15 mm Hg. Conclusions—In intensive care unit patients, mitral E/Ea has a better correlation than BNP with PCWP. Both BNP and mitral E/Ea have high sensitivity for PCWP >15 mm Hg; however, E/Ea appears more specific in this patient population. In patients without cardiac disease, BNP appears more accurate than E/Ea for PCWP >15 mm Hg, whereas E/Ea appears more accurate in patients with cardiac disease.