Pulsed wave tissue Doppler-derived myocardial performance index for the assessment of left ventricular thrombus formation risk after acute myocardial infarction

The prognostic value of Tei index in acute myocardial infarction: a systematic review

Background

Echocardiographic evaluation of left ventricular ejection fraction (LVEF) is used in the risk stratification of patients with an acute myocardial infarction (AMI). However, the prognostic value of the Tei index, an alternative measure of global cardiac function, in AMI patients is not well established.

Methods

We conducted a systematic review, using MEDLINE and EMBASE, to evaluate the prognostic value of the Tei index in predicting adverse outcomes in patients presenting with AMI. The data was collected and narratively synthesised.

Results

A total of 16 studies were including in this review with 2886 participants (mean age was 60 years from 14 studies, the proportion of male patients 69.8% from 14 studies). Patient follow-up duration ranged from during the AMI hospitalisation stay to 57.8 months. Tei index showed a significant association with heart failure episodes, reinfarction, death and left ventricular thrombus formation in 14 out of the 16 studies. However, in one of these studies, Tei index was only significantly predictive of cardiac events in patients where LVEF was <40%. In two further studies, Tei index was not associated with predicting adverse outcomes once LVEF, left ventricular end-systolic volume index and left ventricular early filling time was taken into consideration. In the two remaining studies, there was no prognostic value of Tei index in relation to patient outcomes.

Conclusions

Tei index may be an important prognostic marker in AMI patients, however, more studies are needed to better understand when it should be used routinely within clinical practice.

Tissue Doppler imaging in coronary artery diseases and heart failure

Recent studies have explored the prognostic role of TDI-derived parameters in major cardiac diseases, such as coronary artery disease (CAD) and heart failure (HF). In these conditions, myocardial mitral annular systolic (S’) and early diastolic (E’) velocities have been shown to predict mortality or cardiovascular events. In heart failure non invasive assessment of LV diastolic pressure by transmitral to mitral annular early diastolic velocity ratio (E/E’) is a strong prognosticator, especially when E/E’ is > or =15. Moreover, other parameters derived by TDI, as cardiac time intervals and Myocardial Performance Index, might play a role in the prognostic stratification in CAD and HF. Recently, a three-dimensional (3-D) TDI imaging modality, triplane TDI, has become available, and this allows calculation of 3-Dvolumes and LV ejection fraction. We present a brief update of TDI.

Time intervals and myocardial performance index by tissue Doppler imaging

The application of tissue Doppler imaging (TDI) has shown remarkable growth in clinical practice during the past few years, especially, in risk stratification of patients with coronary heart disease or heart failure (systolic and diastolic). Myocardial performance index (MPI) is a Doppler echocardiographic parameter defined as the sum of the isovolemic contraction and relaxation times divided by the ejection time. It is considered as a reliable parameter to assess global left ventricular function. Cardiac time intervals and MPI have also been found as new applications in diagnosing cardiotoxicity from chemotherapy, COPD, valvular heart disease, pulmonary hypertension and endocrinopathies.

Myocardial tissue Doppler-based indexes to distinguish right ventricular volume overload from right ventricular pressure overload

The objective of this study was to develop tissue Doppler parameters that could be used to differentiate right ventricular (RV) volume overload from RV pressure overload. The RV-pressure-overload group consisted of 40 patients with severe pulmonary hypertension, and the RV-volume-overload group consisted of 40 patients who had an atrial septal defect without evidence of right-to-left shunt, significant pulmonary hypertension, or Eisenmenger's complex. Another 40 healthy subjects were enrolled and served as a control group. Routine echocardiography and tissue Doppler imaging were performed. RV myocardial performance index was determined based on data collected during tissue Doppler imaging over the lateral tricuspid annulus. In patients with RV pressure overload, tissue Doppler parameters showed characteristically lower systolic velocity over the tricuspid annulus (RV myocardial systolic wave [Sm]) and longer isovolumic relaxation time (RV-IVRT). Nevertheless, in patients with RV volume overload, RV-Sm increased significantly, but early-diastolic velocity over tricuspid annulus was relatively low. In conclusion, RV-MPI, RV-Sm/early-diastolic velocity over tricuspid annulus, and RV-IVRT/RV-Sm were all useful to differentiate RV pressure overload from volume overload, although RV-IVRT/RV-Sm was the best parameter, with excellent sensitivity and specificity.

Chronic and acute effects of smoking on left and right ventricular relaxation in young healthy smokers

BACKGROUND

Left ventricular (LV) diastolic dysfunction has been observed in cigarette smokers with coronary artery disease. The aim of the study was to assess LV and right ventricular (RV) diastolic function in healthy, young, and slim smokers before and after smoking one cigarette.

MATERIAL AND METHODS

The participants were 66 healthy volunteers (age < 40 years; body mass index < 25 kg/m(2)): 33 smokers (study group [HS]) and 33 nonsmokers (control group). Echocardiographic examination was done in the HS before smoking one cigarette (HS-1) and after smoking one cigarette (HS-2). To assess diastolic function of LV and RV mitral valve flow (MVF), pulmonary venous flow (PVF) and tricuspid valve flow (TVF) were evaluated.

RESULTS

MVF early to late phase ratio (E/A) was significantly lower in HS-1 and HS-2 than in the control group. The PVF systolic to diastolic phase ratio (S/D) was significantly higher in HS-1 and HS-2 than in the control group. These changes suggest LV diastolic function impairment in the HS, but the MVF pattern remained within the normal range. PVF S/D showed systolic dominance (S/D > 1) typical for impaired LV relaxation and abnormal for this age group. TVF E/A was significantly lower in HS-2 than in HS-1 and control subjects and suggests RV diastolic dysfunction.

CONCLUSIONS

The following conclusion are made: (1) MVF and PVF demonstrate LV relaxation impairment in healthy smokers before and after smoking one cigarette; (2) the assessment of PVF is a good method reflecting LV diastolic function changes, even when MVF remains normal; and (3) TVF shows RV relaxation impairment after smoking one cigarette in healthy smokers.

Usefulness of regional myocardial performance index to diagnose pulmonary embolism in patients with echocardiographic signs of pulmonary hypertension

In this study, myocardial performance index (MPI) was used to identify pulmonary embolism (PE) in patients with echocardiographic signs of pulmonary hypertension. One hundred patients with echocardiographic signs of pulmonary hypertension were enrolled in this study after informed consent was obtained. All patients underwent multidetector-row computed tomography of the chest, and PE was found in 50 patients. Another 100 patients without any cardiopulmonary distress or echocardiographic signs of pulmonary hypertension served as the control group. All cohorts were enrolled after the exclusion of (1) any rhythm other than sinus rhythm; (2) complete bundle branch block; (3) ischemic heart disease proved by stress test, perfusion scan, or coronary angiography; (4) a left ventricular (LV) ejection fraction <50%; and (5) inadequate echocardiograms. Routine echocardiography and tissue Doppler imaging were performed, including the MPIs of the right and left ventricles. The right ventricular (RV) MPI was significantly higher in patients with PE than in others (p <0.0001). Patients without PE had concordant changes in the RV and LV MPIs. In patients with acute PE, the RV MPI became higher, but the LV MPI was relatively constant. Using the RV MPI divided by the LV MPI (the V index), PE could be distinguished in patients with echocardiographic signs of pulmonary hypertension. By receiver-operating characteristic curve analysis, the V index >1.2 identified PE with sensitivity of 82% and specificity of 83%. In conclusion, the V index is a useful parameter to assess the possibility of PE in patients with echocardiographic signs of pulmonary hypertension.

Usefulness of tissue Doppler parameters for identifying pulmonary embolism in patients with signs of pulmonary hypertension

The objective of this study was to use tissue Doppler parameters to identify pulmonary embolism (PE) in patients with echocardiographic signs of pulmonary hypertension. One hundred fifty patients with echocardiographic signs of pulmonary hypertension were enrolled, 50 of whom had PE on multidetector row computed tomography of the chest. Another 150 patients without cardiopulmonary distress or echocardiographic signs of pulmonary hypertension served as a control group. All patients were in sinus rhythm. Routine echocardiography and tissue Doppler imaging were performed. The right ventricular (RV) myocardial performance index (MPI) was obtained during tissue Doppler imaging over the lateral tricuspid annulus. The M index was measured and defined as the peak early diastolic mitral inflow velocity divided by the RV MPI. Statistical analysis was preformed using receiver-operating characteristic curves. Peak early diastolic mitral inflow velocity was significantly less and the RV MPI was significantly greater in patients with PE than in patients without PE (both p values < 0.0001). The RV MPI and the M index were useful in identifying PE in patients with echocardiographic signs of pulmonary hypertension. On statistical analysis, a RV MPI > 0.55 identified PE with a sensitivity of 85% and a specificity of 78%. A M index < 112 had a sensitivity of 92% and a specificity of 92%. In conclusion, the sensitivity and specificity of the RV MPI and the M index to identify PE were excellent. Echocardiography is a useful method to screen for PE.

Pulmonary Embolism and Right Heart Function: Insights from Myocardial Doppler Tissue Imaging

BACKGROUND

Acute pulmonary embolism (PE) has significant impact in right heart function. We assess the difference of Doppler tissue parameters among control subjects, patients with pulmonary hypertension, and patients with acute PE. After optimal treatment, the changes of Doppler tissue parameters in patients with PE were assessed.

METHODS

A total of 50 patients with acute PE, confirmed by multidetector-row chest computed tomography, were enrolled. Another 70 patients with pulmonary hypertension, but no evidence of PE found by computed tomography, were also enrolled. A total of 100 healthy people without signs of cardiopulmonary dysfunction served as a control group. We assessed left and right ventricular (RV) ejection fraction by Simpson's rule. Doppler tissue parameters were obtained from lateral sides of tricuspid and mitral annulus, and interventricular septum. Myocardial performance index (MPI) of RV was estimated from lateral tricuspid annulus by Doppler tissue imaging, MPI of left ventricle from lateral mitral annulus.

RESULTS

The left ventricular and RV ejection fractions in patients with pulmonary hypertension were lower than for the control group and patients with PE. But the RV-MPI in patients with PE was the lowest as a result of significant prolongation of isovolumic relaxation time (IVRT). One month after anticoagulant treatment, the IVRT and RV-MPI recovered in patients with PE. There was no significant correlation between IVRT and pulmonary artery systolic pressure. By bivariate correlation analysis, the most significant factor correlated to pulmonary artery systolic pressure was peak late diastolic velocity of tricuspid annulus with r 0.67, r(2) 0.45, and P less than .0001.

CONCLUSIONS

Acute PE has significant impact in systolic and diastolic function of RV. The higher RV-MPI implies that condition. However, optimal anticoagulant treatment corrects RV dysfunction in patients with PE. After a 1-month course of anticoagulant treatment, RV-MPI diminishes as the result of RV-IVRT reduction.

Right Heart Function in Systemic Lupus Erythematosus: Insights from Myocardial Doppler Tissue Imaging

The purpose of this study was to use Doppler tissue imaging to evaluate heart function and to investigate the correlation between Doppler imaging and pulmonary artery systolic pressure (PASP) and right ventricular (RV) ejection fraction (EF) in patients with systemic lupus erythematosus (SLE). Standard echocardiography and 2-dimensional and color Doppler imaging were used to assess cardiac function in patients given the diagnosis of SLE (n = 40) and healthy control subjects (n = 45). Half of the patients with SLE also presented with pulmonary hypertension (PH). Significant differences in PASP and RV EF (RVEF) were found between the control and SLE groups. The peak systolic velocity of tricuspid annulus was significantly lower in patients with SLE than in the control group. The calculated myocardial performance index of the RV, septum, and left ventricular lateral wall were significantly higher in patients with SLE than in the control group. Bivariate correlation analysis revealed a significant correlation among PASP, RVEF, and systolic tricuspid annular velocity. There was a significant correlation between each of these 3 parameters and the 6-minute walk distance in patients with SLE. Patients with SLE and PH had a significantly shorter 6-minute walk distance than patients with SLE without PH. Furthermore, in patients with SLE and PH, RVEF and systolic tricuspid annular velocity were lower than in the control subjects and patients with SLE without PH. Patients with SLE and PH had a longer isovolumic relaxation time and a higher myocardial performance index of RV than those without PH. Finally, by simple linear regression analysis, we found a significant positive relation between RVEF and systolic tricuspid annular velocity, but a negative relationship between PASP and systolic tricuspid annular velocity. These findings demonstrate that in patients with SLE, systolic tricuspid annular velocity determined by echocardiography and Doppler imaging can be used to assess RV function and PASP. Furthermore, systolic tricuspid annular velocity reflects exercise tolerance in patients with SLE and the length of the isovolumic relaxation time represents the progression of PH.