Right ventricular strain and strain rate properties in patients with right ventricular myocardial infarction

Right ventricular dysfunction in the critically ill. Echocardiographic evaluation

Right ventricular dysfunction is common in critically ill patients, and is associated with increased mortality. Its diagnosis moreover remains challenging. In this review, we aim to outline the potential mechanisms underlying abnormal biomechanics of the right ventricle and the different injury phenotypes. A comprehensive understanding of the pathophysiology and natural history of right ventricular injury can be informative for the intensivist in the diagnosis and management of this condition, and may serve to guide individualized treatment strategies. We describe the main recommended parameters for assessing right ventricular systolic and diastolic function. We also define how to evaluate cardiac output and pulmonary circulation pressures with echocardiography, with a focus on the diagnosis of acute cor pulmonale and relevant applications in critical disorders such as distress, septic shock, and right ventricular infarction.

Assessment of preoperative and postoperative cardiac function in children with adenotonsillar hypertrophy: a prospective cohort study

PURPOSE

Chronic upper airway obstruction caused by adenotonsillar hypertrophy is one of the major cause of morbidity in children. It can lead to Obstructive Sleep Apnoea Syndrome, Pulmonary Hypertension, Cor Pulmonale and right heart failure. The study aimed to evaluate and compare various parameters of cardiac function with the help of echocardiography preoperatively and postoperatively in children undergoing adenotonsillectomy.

METHODOLOGY

A prospective cohort study was conducted on 23 patients at an apex care institute, under the age group of 4-12 years, who were diagnosed with adenotonsillar hypertrophy. Preoperative symptom analysis and Echocardiographic examination were done. After the assessment, all patients underwent surgery in the form of adenotonsillectomy. Follow-up symptom analysis and echocardiographic examination was done after 3 months postoperatively.

RESULTS

Significant improvement in the obstructive symptoms were noted in postoperative group as expected (p =  < 0.001) and also in parameters such as mPAP (p =  < 0.001), TAPSE (p =  < 0.001), TAV (p = 0.001), Ejection fraction (p = 0.027) and RVMPI (p = 0.044) were improved in postoperative group. 4 patients had Grade 1 Right ventricular diastolic dysfunction, which disappeared in three patients postoperatively.

CONCLUSION

We have concluded that there can be subclinical cardiac dysfunctions which occurs as a result of chronic upper airway obstruction due to untreated adenotonsillar hypertrophy. Routine cardiac screening in children presenting with sleep disordered breathing associated with adenotonsillar hypertrophy may be helpful in identifying and preventing the development of cardiopulmonary complication. These changes can be reversed by performing adenotonsillectomy.

13 N-ammonia PET-derived right ventricular longitudinal strain and myocardial flow reserve in right coronary artery disease

PURPOSE

We developed a feature-tracking algorithm for use with electrocardiography-gated high-resolution ¹³ N-ammonia positron emission tomography (PET) imaging, and we hypothesized it could be used to clarify the association between right ventricular (RV) longitudinal strain (LS) and right coronary artery (RCA) ischemia. The aim of this study was to investigate the association between the reduction of regional myocardial flow reserve (MFR) in RCA territories and PET-derived LS of the RV free wall.

METHODS

Ninety-three patients with coronary artery stenosis > 50%, diagnosed by coronary computed tomography angiography, and 10 controls were retrospectively analyzed. RV-LS in the free wall was measured by a feature-tracking technique on the resting and stressed ¹³ N-ammonia PET images of horizontal long axis slices. The patients were sub-grouped according to regional MFR values at the territories of RCA, left anterior descending artery (LAD), and left circumflex coronary artery (LCx): RCA-MFR < 2.0 [n = 34], RCA-MFR ≥ 2.0 but MFR < 2.0 at LAD or LCx territories [n = 11], and MFR ≥ 2.0 for all territories [n = 48]. Stress and resting RV-LS were compared in each of the four groups. Multiple comparisons of RV-LS among the four groups were performed in the stress and resting state.

RESULTS

Decreased stress RV-LS in patients with an RCA-MFR < 2.0 was observed. In the patients with MFR ≥ 2.0 for all territories, the stressed RV-LS was significantly increased compared to that in the resting state. Significantly decreased RV free wall LS during adenosine stress in patients with RCA-MFR < 2.0 was observed in the other three groups.

CONCLUSIONS

We measured RV myocardial LS using feature tracking in cine imaging of ¹³ N-ammonia PET. The results of this study suggest that PET-derived stressed RV-LS is useful for detecting reduced RV myocardial motion due to ischemia in the RCA territory.

The impact of right ventricular function assessed by 2-dimensional speckle tracking echocardiography on early mortality in patients with inferior myocardial infarction

BACKGROUND

Right ventricular (RV) involvement in inferior myocardial infarction (MI) increases in-hospital morbidity and mortality.

HYPOTHESIS

RV systolic dysfunction assessed by 2-dimensional speckle tracking echocardiography (STE) might be a predictor of early mortality in patients with acute inferior MI.

METHODS

Eighty-one consecutive patients with acute inferior MI (mean age, 60.8 ± 12.7 years; 18 females) were included. RV myocardial involvement was defined as an elevation >1 mm in V₁ or V₄ R within 12 hours of symptom onset. RV function was assessed by STE. Patients were followed for 30 days for all-cause mortality.

RESULTS

Thirty-eight patients had RV myocardial involvement, and they had significantly lower tricuspid annular plane systolic excursion (TAPSE), tricuspid annular systolic velocity (RVS), and left ventricular (LV) and RV global longitudinal strain (GLS). Nine patients (11%) died within 30 days. The mean age of mortality group was higher with more female frequency. They had significantly higher pro-BNP, hs-troponin T, and creatinine levels, but lower hemoglobin levels. TIMI 3 flow was significantly less achieved in mortality group. RV myocardial involvement was more frequent in the mortality group, and they had significantly lower TAPSE, RVS, and LV and RV GLS. Multivariate analysis revealed that age and RV GLS were independent predictors of early mortality. RV GLS ≤ -14% predicted early mortality in patients with acute inferior MI with a sensitivity of 88.9% and a specificity of 62.5% (AUC: 0.817, P = 0.002).

CONCLUSIONS

RV GLS may be useful in predicting early mortality in patients with acute inferior MI.

The Role of Doppler Imaging in the Assessment of Right Ventricular Function: a Case-control Study of Acute Inferior Wall Infarction

Background

Right ventricular infarction (RVI) develops in 30-50% of patients with inferior wall infarction (IWI). The rates of mortality, morbidity, and complications in these patients are greater than in the patients without RVI. We compared the tissue Doppler imaging (TDI) indices between a group of patients with IWI and RVI, with a similar group of patients who had IWI alone to investigate the application of TDI indices in the evaluation and detection of right ventricular function.

Material and Methods

We studied 49 patients with first acute IWI in two groups. Group 1 (N=24) were patients with IWI and RVI while group 2 consisted of patients with IWI alone (N=25), based on standard electrocardiogram criteria. The peak systolic (Sm), peak early (Em) and late (Am) diastolic velocities, and Em/Am ratio were obtained from the apical four chamber view, at the lateral side of the tricuspid annulus. We measured trans-tricuspid early (ET) and peak (AT) filling velocity, ET/AT ratio, right ventricular end diastolic diameter (RVEDD), and tricuspid annular plane systolic excursion (TAPSE) by M-mode TDI projected at the long axis of parasternal view.

Results

The RVEDD and E/Em ratio were increased, while the TAPSE was significantly decreased in the patients with RVI as compared to those without RVI (4.7± 0.6 vs. 3.1±0.2 cm; p < 0.005, 5.6±2.21 Vs 4.5±1.2; p<0.006 and 1.7±0.4 vs. 2.3±0.5 cm; p <0.0001, respectively). However, the other statistically measured parameters were not significantly different between these groups.

Conclusion

The measurement of RVEDD, E/Em ratio, and TAPSE, as right ventricular myocardial systolic and diastolic parameters by pulse wave TDI could be used to objectively assess the status of RV condition in patients with first acute IWI.

Principles of transthoracic echocardiographic evaluation

Transthoracic echocardiography is the most widely used imaging test in cardiology. Although completely noninvasive, transthoracic echocardiography has a well-established role in the diagnosis of numerous cardiovascular diseases, and also provides critical qualitative and quantitative information on their prognosis and pathophysiological processes. The aim of this Review is to outline the broad principles of transthoracic echocardiography, including the traditional techniques of two-dimensional, colour, and spectral Doppler echocardiography, and newly developed advances including tissue Doppler, myocardial deformation imaging, torsion, stress echocardiography, contrast and three-dimensional echocardiography. The advantages and disadvantages, clinical application, prognostic value, and salient research findings of each modality are described. Advances in complex imaging techniques are expected to continue unabated, and this Review highlights technical improvements that will influence the diagnosis and improve our understanding of cardiovascular function and disease.

Right ventricular involvement in anterior myocardial infarction: a tissue Doppler-derived strain and strain rate study

OBJECTIVE

Strain and strain rate imaging is currently the most popular echocardiographic technique that reveals subclinical myocardial damage. There are currently no available data on this imaging method with regard to assessing right ventricular involvement in anterior myocardial infarction. Therefore, we aimed to evaluate right ventricular regional functions using a derived strain and strain rate imaging tissue Doppler method in patients who were successfully treated for their first anterior myocardial infarction.

METHODS

The patient group was composed of 44 patients who had experienced their first anterior myocardial infarction and had undergone successful percutaneous coronary intervention. Twenty patients were selected for the control group. The right ventricular myocardial samplings were performed in three regions: the basal, mid, and apical segments of the lateral wall. The individual myocardial velocity, strain, and strain rate values of each basal, mid, and apical segment were obtained.

RESULTS

The right ventricular myocardial velocities of the patient group were significantly decreased with respect to all three velocities in the control group. The strain and strain rate values of the right mid and apical ventricular segments in the patient group were significantly lower than those of the control group (excluding the right ventricular basal strain and strain rate). In addition, changes in the right ventricular mean strain and strain rate values were significant.

CONCLUSION

Right ventricular involvement following anterior myocardial infarction can be assessed using tissue Doppler based strain and strain rate.

Right ventricular longitudinal deformation parameters and exercise capacity : prognosis of patients with chronic thromboembolic pulmonary hypertension

OBJECTIVE

Chronic thromboembolic pulmonary hypertension (CTEPH) is a progressive disease characterized by increased pulmonary vascular resistance resulting in pulmonary hypertension and right heart failure. The six-minute walk test (6MWT) distance is associated with the prognosis of CTEPH patients. Speckle tracking echocardiography (STE) is a reliable method for determining ventricular function. The aim of this study was to assess and compare the right ventricular (RV) function of CTEPH patients according to their 6MWT distances.

METHODS

Forty-nine consecutive CTEPH patients (mean age, 50 ± 16 years; 22 male) who were referred to our center for pulmonary thromboendarterectomy (PTE) were included in the study. All patients underwent the 6MWT and right heart catheterization (RHC). Standard echocardiography and STE were performed on all patients before PTE. Patients were divided into two groups based on their 6MWT distance being less or more than 300 m.

RESULTS

Patients with a shorter 6MWT distance had a significantly larger RV, while they had a significantly lower RV fractional area change and higher myocardial performance index suggesting impaired RV function. Both RV basal-lateral strain and strain rate measures were significantly lower in patients with shorter 6MWT distances than those with longer 6MWT distances. Similarly, they had lower RV basal-septal, mid-lateral, and global strain measures. 6MWT distances were correlated with RV basal-lateral and mid-lateral strain measures (r = 0.349, p = 0.025 and r = 0.415, p = 0.008, respectively).

CONCLUSION

Our data suggest that RV myocardial deformation parameters are associated with 6MWT distances. Determination of RV dysfunction by STE may be helpful in identifying patients with a poor prognosis.

The significance of right-sided chest leads in exercise testing for the detection of right ventricular dysfunction post myocardial infarction of the inferior wall

BACKGROUND

The incorporation of right-sided chest leads (V(3)R-V(5)R) into the standard exercise testing has been reported to improve its diagnostic accuracy. The purpose of this study was to evaluate the ability of exercise testing in detecting right ventricular (RV) dysfunction post myocardial infarction (MI) of the inferior wall, using additional V(3)R-V(5)R leads.

METHODS

We studied 133 patients (59 ± 5 years, 81 males) with a history of inferior MI due to right coronary artery obstruction (affirmed with coronary angiography). All patients underwent an echocardiographic assessment of RV function 4 weeks after discharge and an exercise treadmill test in order to detect possible RV dysfunction. Recordings during exercise were obtained with the standard 12 leads plus V(3)R-V(5)R.

RESULTS

From 133 patients, 97 (group A) presented with normal right ventricle according to the echocardiographic study while the rest 36 patients (group B) presented with RV dysfunction. Maximal exercise-induced ST-segment deviation (in mm) was similar in the standard 12 leads for the 2 groups (2.1 ± 0.4 vs 1.8 ± 0.3, p = NS) while in V(3)R-V(5)R it was greater in group B (0.7 ± 0.3 vs 1.4 ± 0.4, p<0.05). Sensitivity, positive prognostic value, negative prognostic value and accuracy of exercise testing in detecting RV dysfunction were all improved using V(3)R-V(5)R (78 vs 47%, 39 vs 29%, 87 vs 75%, 62 vs 55% respectively, p<0.05 for all) while specificity was not deteriorated (56 vs 58%, p = NS).

CONCLUSIONS

The addition of right-sided chest leads (V(3)R-V(5)R) improves the diagnostic ability of standard exercise testing in detecting and especially in excluding RV dysfunction post inferior MI.

Right ventricular involvement in patients with coronary artery disease

PURPOSE OF REVIEW

RV involvement in coronary artery disease (CAD) includes isolated infarction and involvement in left ventricular infarction. Right ventricular involvement with left ventricular infarction has unique clinical signs and symptoms, requires different management, and has worse prognosis than left ventricular infarcts without right ventricular involvement. Although the right ventricle (RV) is geometrically complex, advances in echocardiography, nuclear imaging, computed tomography, and magnetic resonance imaging technologies have helped to optimally visualize its structure and function and to better elucidate its role in CAD.

RECENT FINDINGS

Newer noninvasive imaging modalities to visualize the RV are highlighted and their emerging clinical utilities are emphasized, including three-dimensional echocardiography, tissue Doppler velocity and strain imaging, computed tomography, and MRI.

SUMMARY

The RV is often involved in CAD. Available imaging modalities demonstrate different aspects of right ventricular involvement, yielding new insights into pathophysiology, clinical care, and management. As imaging technologies widen in their scope, cardiologists will increasingly have the imaging tools to integrate information on right ventricular morphology, hemodynamics, and function, enabling appropriate care for patients with right ventricular involvement in CAD.

Assessment of right ventricular diastolic function by tissue Doppler imaging in patients with acute right ventricular myocardial infarction

BACKGROUND

It is known that right ventricular systolic parameters as assessed by color tissue Doppler imaging (TDI) are abnormal in patients with inferior wall ST elevation myocardial infarction (IWMI) with right ventricular myocardial infarction (RVMI). This study was undertaken to determine right ventricular diastolic function as assessed by TDI in patients with acute RVMI.

METHODS

Thirty-five patients with first IWMI were studied and compared with 20 age-matched healthy controls, and categorized into those with (14 patients) and without (21 patients) RVMI based on standard ECG criteria. Peak systolic, peak early and late diastolic velocities (Sm, Em, and Am), Em/Am ratio along with time to Sm (ECG Q-Sm) and time to Em (ECG Q-Em) were acquired from the apical 4-chamber view at the lateral side of tricuspid annulus using TDI.

RESULTS

Sm, Em, and Em/Am ratio was reduced significantly in patients with RVMI as compared with those without RVMI and healthy individuals (Sm [11.1 + or - 2.9] vs. [14 + or - 1.9] and [14.5 + or - 2.1] cm/sec, P < 0.01; Em [9.2 + or - 3.5] vs. [12.9 + or - 3] and [14.0 + or - 2.0] cm/sec, P < 0.01; Em/Am ratio 0.53 + or - 0.2 vs. 0.78 + or - 0.19 and 0.8 + or - 0.3 [P < 0.0001]). Among the intervals, there was significant prolongation of Q-Em (558 + or - 14.8 vs. 507 + or - 16.2 and 480 + or - 20 ms [P < 0.0001]) but Q-Sm and Am were not statistically different between the groups.

CONCLUSION

Right ventricular TDI diastolic parameters are abnormal in patients with RVMI. The method of recording the velocities and time intervals are simple and can be used to assess right ventricular diastolic function in patients with RVMI. (Echocardiography 2010;27:539-543).

Echocardiographic tissue deformation imaging quantifies abnormal regional right ventricular function in arrhythmogenic right ventricular dysplasia/cardiomyopathy

BACKGROUND

The aim of this study was to determine the accuracy of new quantitative echocardiographic strain and strain-rate imaging parameters to identify abnormal regional right ventricular (RV) deformation associated with arrhythmogenic right ventricular dysplasia/cardiomyopathy (ARVD/C).

METHODS

A total of 34 patients with ARVD/C (confirmed by Task Force criteria) and 34 healthy controls were prospectively enrolled. Conventional echocardiography, including Doppler tissue imaging (DTI), was performed. Doppler and two-dimensional strain-derived velocity, strain, and strain rate were calculated in the apical, mid, and basal segments of the RV free wall.

RESULTS

RV dimensions were significantly increased in patients with ARVD/C (RV outflow tract 19.3+/-5.2 mm/m2 vs 14.1+/-2.2 mm/m2, P<.001; RV inflow tract 23.4+/-4.8 mm/m2 vs 18.8+/-2.4 mm/m2, P<.001), whereas left ventricular dimensions were not significantly different compared with controls. Strain and strain rate values were significantly lower in patients with ARVD/C in all 3 segments. All deformation parameters showed a higher accuracy to detect functional abnormalities compared with conventional echocardiographic criteria of dimensions or global systolic function. The lowest DTI strain value in any of the 3 analyzed segments showed the best receiver operating characteristics (area under the curve 0.97) with an optimal cutoff value of -18.2%.

CONCLUSIONS

DTI and two-dimensional strain-derived parameters are superior to conventional echocardiographic parameters in identifying ARVD/C. This novel technique may have additional value in the diagnostic workup of patients with suspected ARVD/C.

Strain and strain rate imaging by echocardiography - basic concepts and clinical applicability

Echocardiographic strain and strain-rate imaging (deformation imaging) is a new non-invasive method for assessment of myocardial function. Due to its ability to differentiate between active and passive movement of myocardial segments, to quantify intraventricular dyssynchrony and to evaluate components of myocardial function, such as longitudinal myocardial shortening, that are not visually assessable, it allows comprehensive assessment of myocardial function and the spectrum of potential clinical applications is very wide. The high sensitivity of both tissue Doppler imaging (TDI) derived and two dimensional (2D) speckle tracking derived myocardial deformation (strain and strain rate) data for the early detection of myocardial dysfunction recommend these new non-invasive diagnostic methods for extensive clinical use. In addition to early detection and quantification of myocardial dysfunction of different etiologies, assessment of myocardial viability, detection of acute allograft rejection and early detection of allograft vasculopathy after heart transplantation, strain and strain rate data are helpful for therapeutic decisions and also useful for follow-up evaluations of therapeutic results in cardiology and cardiac surgery. Strain and strain rate data also provide valuable prognostic information, especially prediction of future reverse remodelling after left ventricular restoration surgery or after cardiac resynchronization therapy and prediction of short and median-term outcome without transplantation or ventricular assist device implantation of patients referred for heart transplantation.The Review explains the fundamental concepts of deformation imaging, describes in a comparative manner the two major deformation imaging methods (TDI-derived and speckle tracking 2D-strain derived) and discusses the clinical applicability of these new echocardiographic tools, which recently have become a subject of great interest for clinicians.

Non-invasive investigations of the right heart: how and why?

The importance of right ventricular (RV) function in the clinical management of patients with cardiopulmonary disorders is now well recognized. However, due to both its shape and location and to the load dependence of its ejection fraction, accurate evaluation of its function is still a challenge. Echocardiography allows morphological, hemodynamic and functional assessment of the right heart. Displacement and deformation parameters derived from new techniques are promising tools. 3D echocardiography also has a potential interest in the quantification of RV volumes and ejection fraction. Radionuclide technique allows an easy and accurate measurement of right ventricular ejection fraction. MRI remains nowadays the technique of choice for the quantification of volumes and function of the RV. All these techniques have proven their interest in various diseases affecting the right heart. RV function is an important prognostic factor in heart failure and is a major component of functional capacity in such patients. In pulmonary arterial hypertension, echocardiography is the best tool for the routine follow-up of patients. Finally, all these non-invasive techniques of investigation of the right heart enable the diagnosis of specific right ventricular damage such as myocardial infarction or arrhythmogenic right ventricular dysplasia.

Persistent regional diastolic dysfunction after myocardial ischemia and the effect of statin treatment: assessment with two-dimensional radial strain rate

BACKGROUND

Persistence of regional diastolic dysfunction after ischemic insult remains debatable. With speckle tracking echocardiography (STE), we sought to (1) prove the persistence of regional diastolic dysfunction, (2) assess the feasibility of applying persistent regional diastolic dysfunction to differentiating ischemic and nonischemic chest pain, and finally (3) examine statin effects on postischemic regional diastolic dysfunction.

METHODS

Nineteen patients with variant angina (VA) and 12 normal subjects were enrolled. Comprehensive echocardiographic examinations were performed before and 1 day after coronary angiography (CAG) with ergonovine provocation. Radial systolic (rSRsys) and diastolic (rSRdia) strain rates were obtained and averaged using standard segmentation models corresponding to the three major coronary territories assigned.

RESULTS

No significant changes in rSRsys and rSRdia values were observed for controls and in rSRsys for VA. However, rSRdia for VA demonstrated a weak, but significant, decrease from -2.25 +/- 0.71/sec to -2.04 +/- 0.71/sec (P = 0.003) 1 day after CAG. However, because of the wide overlap between rSRdia values in normal and ischemic segments for VA patients, predictability of remote ischemia based solely on the rSRdia was limited. Subgroup analysis according to statin prescription showed that statin administration contributed to the elimination of rSRdia reduction (-2.28 +/- 0.84/sec on pre-CAG vs. -2.29 +/- 0.77/sec on post-CAG, P = 0.72 for patients without statin premedication; -2.23 +/- 0.64/sec for pre-CAG vs. -1.88 +/- 0.65/sec for post-CAG, P = 0.002 for those without). Expectedly, rSRsys values showed no significant changes in all situations.

CONCLUSIONS

The presence and sustained nature of regional diastolic dysfunction can be demonstrated with STE. Statin minimized the persistence of regional diastolic dysfunction after an acute ischemia. Although the clinical usefulness of rSRdia by STE appears to be limited, its clinical utility requires further consideration, given the brevity of the ischemia provoked during CAG with ergonovine and the protracted regional diastolic dysfunction.