Left ventricular myocardial strain quantification with two- and three-dimensional cardiovascular magnetic resonance based tissue tracking

Three-Dimensional Feature Tracking Study of Healthy Chinese Ventricle by Cardiac Magnetic Resonance

PURPOSE

Myocardial strain, as a crucial quantitative indicator of myocardial deformation, can detect the changes of cardiac function earlier than parameters such as ejection fraction (EF). It has reported that cardiac magnetic resonance(CMR) and post-processing software possess the ability to obtain the stability and repeatability strain values. Recently, the normal strain values range of people are debatable, especially in the Chinese population. Therefore, we aim to explore the ventricular characteristics and the myocardial strain values of the Chinese people by using the cardiac magnetic resonance feature tracking (CMR-FT). Additionally, we attempted to use the myocardial and chordae tendineae contours to calculate the ventricular volumes by the CMR-FT. This study may provide valuable insights into the application of CMR-FT in tracking the ventricular characteristics and myocardial strain for Chinese population, especially in suggesting an referable myocardial strain parameters of the Chinese.

METHODS

A total of 109 healthy Chinese individuals (age range: 18 to 58 years; 52 males and 57 females) underwent 3.0T CMR to acquire the cardiac images. The commercial post-processing software was employed to analyse the image sequence by semi-automatic processing, then the biventricular morphology (End-Diastolic Volume, EDV; EDV/Body Surface Area, EDV/BSA), function(EF; Cardiac Output, CO; Cardiac Index, CI) and strain(Radial Strain, RS; Circumferential Strain, CS; Longitudinal Strain, LS) values were obtained.The biventricular myocardial strain values were stratified according to the age and gender. The Left Ventricular( LV base, mid, apex) and myocardial strain values of three coronary artery areas were calculated based on the the strain value of LV American Heart Association(AHA) 16 segments.

RESULTS

It was shown that the females had larger LV globe strain values compared with the males (LVGPRS: 42.0 ± 8.5 versus 33.6 ± 6.2%, P < 0.001; LVGPCS: -21.2 ± 2.1 versus - 19.7 ± 2.3%, P < 0.001; LVGPLS: -16.4 ± 2.6 versus - 14.6 ± 2.2%, P < 0.001;). Moreover, the differences in RS, CS, and LS among the LV myocardium 16 segments were obvious. However, the right ventricle (RV) strain values showed non-normal distribution in the volunteers of this research.

CONCLUSIONS

Here, we successfully tracked the characteristics of bilateral ventricles in healthy Chinese populations through using the 3.0T CMR. We confirmed that there was a gender difference in LV Globe Strain values. In addition, we obtained strain values for each myocardial segment of the LV and different coronary artery regions based on the AHA 16 segments method, Our results also showed that the RV strain values with a non-normal distribution, and RV global strain values were not related to the gender and age. Furthermore, LVGPRS, LVGPLS, and RVGPRS were significantly correlated with BMI, CO, CI, and EDV in the Chinese population.

Myocardial deformation characteristics assessed by cardiovascular magnetic resonance feature tracking in a healthy Chinese population

Purpose

To explore global/regional myocardial deformation across various layers, vascular distributions, specific levels and distinct walls in healthy individuals using cardiovascular magnetic resonance feature tracking (CMR-FT).

Methods

We selected a cohort of 55 healthy participants and CMR cine images were used to obtain the left ventricular (LV) peak longitudinal, circumferential, radial strains (LS, CS, RS). The characteristics of normal LV strain in various layers (endocardium, myocardium, epicardium), territories [left anterior descending artery (LAD), left circumflex artery (LCX), and right coronary artery (RCA)], levels (basal, middle, apical) and walls (anterior, septum, inferior, lateral) were compared.

Results

The absolute values of the LV global LS and CS gradually decreased from endocardium to epicardium. The absolute LV global RS (65.7 ± 47.7%) was maximum relative to LS (-22.0 ± 10.8%) and CS (-22.8 ± 7.7%). The absolute values of the LCX territorial strain were the largest compared with the LAD and RCA territorial strains. Regional RS, endo-CS and endo-LS gradually increased from the basal to the apical level. The LV lateral walls had the highest strain values (CS, LS, and RS).

Conclusions

Variations in normal LV strain values across various layers, territories, levels, and walls were observed, suggesting the necessity for careful clinical interpretation of these strain values. These findings also partially revealed the complexity of normal cardiac mechanics.

Myocardial Strain Measurements Derived From MR Feature-Tracking: Influence of Sex, Age, Field Strength, and Vendor

BACKGROUND

Cardiac magnetic resonance feature tracking (CMR-FT) is a novel technique for assessing myocardial deformation and dysfunction. However, a comprehensive assessment of normal values of strain parameters in all 4 cardiac chambers using different vendors is lacking.

OBJECTIVES

This study aimed to characterize the normal values for myocardial strain in all 4 cardiac chambers and identify factors that contribute to variations in FT strain through a systematic review and meta-analysis of the CMR-FT published reports.

METHODS

The investigators searched PubMed, Embase, and Scopus for myocardial strains of all 4 chambers measured by CMR-FT in healthy adults. The pooled means of all strain parameters were generated using a random-effects model. Subgroup analyses and meta-regressions were performed to identify the sources of variations.

RESULTS

This meta-analysis included 44 studies with a total of 3,359 healthy subjects. The pooled means of left ventricular global longitudinal strain (LV-GLS), LV global radial strain, and LV global circumferential strain (GCS) were -18.4% (95% CI: -19.2% to -17.6%), 43.7% (95% CI: 40.0%-47.4%), and -21.4% (95% CI: -22.3% to -20.6%), respectively. The pooled means of left atrial (LA)-GLS (corresponding to total strain, passive strain, and active strain) were 34.9% (95% CI: 29.6%-40.2%), 21.3% (95% CI: 16.6%-26.1%) and 14.3% (95% CI: 11.8%-16.8%), respectively. The pooled means of right ventricular (RV)-GLS and right atrial global longitudinal total strain were -24.0% (95% CI: -25.8% to -22.1%) and 36.3% (95% CI: 15.5%-57.0%), respectively. Meta-regression identified field strength (P < 0.001; I2 = 98.6%) and FT vendor (P < 0.001; I2 = 98.5%) as significant confounders contributing to heterogeneity of LV-GLS. The variations of LA-GLSactive were associated with regional distribution (P < 0.001; I2 = 97.3%) and FT vendor (P < 0.001; I2 = 97.4%). Differences in FT vendor were attributed to variations of LV-GCS and RV-GLS (P = 0.02; I2 = 98.8% and P = 0.01; I2 = 93.8%).

CONCLUSIONS

This study demonstrated the normal values of CMR-FT strain parameters in all 4 cardiac chambers in healthy subjects. Differences in FT vendor contributed to the heterogeneity of LV-GLS, LV-GCS, LA-GLSactive, and RV-GLS, whereas sex, age, and MR vendor had no effect on the normal values of CMR-FT strain measurements.

Identification of patients with nonischemic dilated cardiomyopathy at risk of malignant ventricular arrhythmias: insights from cardiac magnetic resonance feature tracking

BACKGROUND

Patients with nonischemic dilated cardiomyopathy (NIDCM) are prone to arrhythmias, and the cause of mortality in these patients is either end-organ dysfunction due to pump failure or malignant arrhythmia-related death. However, the identification of patients with NIDCM at risk of malignant ventricular arrhythmias (VAs) is challenging in clinical practice. The aim of this study was to evaluate whether cardiovascular magnetic resonance feature tracking (CMR-FT) could help in the identification of patients with NIDCM at risk of malignant VAs.

METHODS

A total of 263 NIDCM patients who underwent CMR, 24-hour Holter electrocardiography (ECG) and inpatient ECG were retrospectively evaluated. The patients with NIDCM were allocated to two subgroups: NIDCM with VAs and NIDCM without VAs. From CMR-FT, the global peak radial strain (GPRS), global longitudinal strain (GPLS), and global peak circumferential strain (GPCS) were calculated from the left ventricle (LV) model. We investigated the possible predictors of NIDCM combined with VAs by univariate and multivariate logistic regression analyses.

RESULTS

The percent LGE (15.51 ± 3.30 vs. 9.62 ± 2.18, P < 0.001) was higher in NIDCM patients with VAs than in NIDCM patients without VAs. Furthermore, the NIDCM patients complicated with VAs had significantly lower GPCS than the NIDCM patients without VAs (- 5.38 (- 7.50, - 4.22) vs.-9.22 (- 10.73, - 8.19), P < 0.01). Subgroup analysis based on LGE negativity showed that NIDCM patients complicated with VAs had significantly lower GPRS, GPCS, and GPLS than NIDCM patients without VAs (P < 0.05 for all). Multivariate analysis showed that both GPCS and %LGE were independent predictors of NIDCM combined with VAs.

CONCLUSIONS

CMR global strain can be used to identify NIDCM patients complicated with VAs early, specifically when LGE is not present. GPCS < - 13.19% and %LGE > 10.37% are independent predictors of NIDCM combined with VAs.

Evaluation of left ventricular diastolic function in patients with coronary microvascular dysfunction via cardiovascular magnetic resonance feature tracking

Background

Coronary microvascular dysfunction (CMD) has been suggested to be one of the pathologic mechanisms contributing to heart failure with preserved left ventricular ejection fraction (LVEF) and left ventricular (LV) diastolic dysfunction. We therefore aimed to evaluate LV diastolic function in patients with CMD using cardiovascular magnetic resonance feature tracking (CMR-FT).

Methods

We prospectively enrolled 115 patients referred to cardiology clinics for chest pain assessment who subsequently underwent coronary computed tomography angiogram and stress perfusion CMR. CMD was defined as the presence of subendocardial inducible ischemia detected through visual assessment. LV diastolic function was evaluated using CMR-derived volume-time curves and CMR-FT parameters. The former included early peak filling rate (PFR) and time to PFR; the latter included LV global/regional peak longitudinal diastolic strain rate (LDSR), circumferential diastolic strain rate (CDSR), and radial diastolic strain rate (RDSR).

Results

A total of 92 patients with 1,312 segments were eventually included. Of these, 19 patients were classified as non-CMD (48.8±11.2 years; 63.2% male) and 73 as with CMD (52.3±11.9 years; 54.8% male). The LVEFs were similar and preserved in both groups (P=0.266). At the per-patient level, no differences were observed in PFR, time to PFR, or LV global diastolic strain rates between the two groups. At the per-segment level, 51% (665/1,312) of the myocardial segments were classified as CMD, whereas 49% (647/1,312) were classified as non-CMD. CMD segments showed significantly lower regional CDSR (P=0.019) and RDSR (P=0.006) compared with non-CMD segments.

Conclusions

Despite normal LV ejection fraction in CMD patients, decreased LV diastolic function in CMD myocardial segments indicates early diastolic impairment.

Value of cardiac magnetic resonance feature tracking technology in the differential diagnosis of isolated left ventricular noncompaction and dilated cardiomyopathy

Background

This study explored the value of myocardial strain in the differential diagnosis of isolated left ventricular myocardial noncompaction (ILVNC) and dilated cardiomyopathy (DCM) using cardiac magnetic resonance (CMR) feature tracking technology.

Methods

This retrospective analysis was performed on consecutive patients (25 with ILVNC, 30 with DCM, and 30 healthy controls) presenting to Shanxi Cardiovascular Hospital. All ILVNC patients met echocardiographic and CMR criteria for ventricular non-compaction. All patients with DCM met the 2016 American Heart Association and 2018 Chinese Medical Association Cardiovascular Branch diagnostic criteria. cvi42 software (Circle Cardiovascular Imaging) was used to measure radial, circumferential, and longitudinal strain (LS) globally and in segments of the left ventricle. Analysis of variance was used to compare strains among groups and among different segments within the same group. Receiver operating characteristic (ROC) curves were used to evaluate the diagnostic efficacy of different parameters in ILVNC and DCM.

Results

Basal circumferential strain was lower in the DCM than in the ILVNC group (P=0.05). Both median and apical LS were lower in the ILVNC than in DCM group (P=0.02 and P=0.01, respectively). ROC curves showed that apical LS was the most effective in distinguishing ILVNC from DCM [area under the curve (AUC) =0.883; P<0.001; 95% CI: 0.850-0.977]. Comparing strains among different segments within the same group revealed that in DCM, the circumferential and LS of the apex were higher than those of the basal segment, which is consistent with the pattern in healthy controls; however, has no such regular pattern was seen in ILVNC.

Conclusions

Myocardial strain parameters are of considerable value in the differential diagnosis of ILVNC and DCM. Differences in patterns between ILVNC and DCM can be sensitively identified, providing more comprehensive information for early clinical diagnosis.

Heart failure with preserved ejection fraction in post myocardial infarction patients: a myocardial magnetic resonance (MR) tissue tracking study

Background

This study aimed to explore the value of cardiac magnetic resonance tissue tracking (CMR-TT) technology in evaluating heart failure with preserved ejection fraction (HFpEF) in patients with chronic myocardial infarction (CMI).

Methods

Between June 2016 and March 2022, we included a consecutive series of 92 patients with CMI and 40 healthy controls in this retrospective study. The CMI patients enrolled were divided into different subgroups [HFpEF-CMI group (n=54) and non- heart failure (HF)-CMI group (n=38)] according to the Heart Failure Association (HFA)-PEFF (step 1: P, pre-test assessment; step 2: E, echocardiography and natriuretic peptide score; step 3: F1, functional testing; step 4: F2, final aetiology) diagnostic algorithm. CMR scan was performed at the First Hospital of China Medical University. Quantitative measurements of myocardial damage, such as myocardial strain parameters of both ventricles derived by CMR-TT and infarct size and transmurality by late gadolinium enhancement (LGE), were assessed. One-way analysis of variance, independent samples t-test, and rank sum test were used to compare myocardial impairment among groups. Pearson or Spearman correlation coefficient was used to measure correlations between left ventricular (LV) strains and clinical and functional parameters. Logistic regression analysis and receiver operating characteristic (ROC) curve were performed to identify the best parameter for diagnosing HFpEF-CMI.

Results

HFpEF-CMI patients demonstrated significantly impaired LV strains and strain rates in all of the three directions (radial, circumferential and longitudinal) compared to non-HF-CMI patients and healthy controls (P<0.001 for all), whereas only global longitudinal strain (GLS) was significantly impaired in HFpEF-CMI patients vs. controls for right ventricular strain parameters (P<0.001). LV strains showed moderate correlation with N-terminal pro-brain natriuretic peptide (radial, circumferential and longitudinal strain, R=-0.401, R=0.408, R=0.407, respectively, P<0.001 for all). LV strains in the three directions (radial, circumferential and longitudinal) [area under ROC curve (AUC) =0.707, 95% confidence interval (CI): 0.603-0.797; AUC =0.708, 95% CI: 0.604-0.798; AUC =0.731, 95% CI: 0.628-0.818; respectively, P<0.01 for all] were discriminators for HFpEF-CMI and non-HF-CMI. LV strains and myocardial infarction volume were independent factors in multi-logistic regression analysis after adjusting for body mass index, age, and sex (P<0.05 for all).

Conclusions

CMR-TT provides clinicians with useful additional imaging parameters to facilitate the assessment of CMI patients with HFpEF. LV strain parameters can detect early cardiac insufficiency in patients with HFpEF-CMI and have potential value for discriminating between HFpEF and non-HF patients post-CMI.

Left ventricular strain in patients with Takayasu arteritis with preserved ejection fraction: an analysis using cardiac magnetic resonance imaging feature tracking

Background

The alteration of myocardial strain in patients with Takayasu arteritis (TAK) remains unclear. This study aimed to evaluate left ventricular (LV) stain in patients with TAK and preserved left ventricular ejection fraction (pLVEF) using cardiac magnetic resonance imaging feature tracking (CMR-FT) to analyze risk factors for impaired LV strain and to compare the baseline difference of LV strain between patients with reduced and nonreduced LVEF at 6-month follow-up.

Methods

In all, 51 patients with TAK and 30 healthy controls were prospectively enrolled. All participants underwent multiple short- and long-axis cine scans with true fast imaging with steady-state precession sequence. In this observational study, LV global and regional longitudinal, circumferential, and radial strain and their strain rates were analyzed with FT on cine images. The relationship between LV strain and clinical data was explored. The baseline LV strain between patients with TAK and reduced and nonreduced LVEF was compared using transthoracic echocardiography (TTE) at the 6-month follow-up.

Results

Patients with TAK with pLVEF showed a decline in baseline global longitudinal peak strain (GLS) [TAK (-13.35%±3.11%) vs. controls (-14.77%±1.74%), P=0.021] and circumferential peak strain (GCS) [TAK (-21.46%±2.66%) vs. controls (-22.75%±2.57%), P=0.027] in comparison with normal controls. The longitudinal peak strain (LPS) in the apical (P=0.003) and midventricular regions (P=0.027) and the circumferential peak strain (CPS) in the basal (P=0.021) and midventricular regions (P=0.008) also decreased in patients with TAK. Patients with pulmonary hypertension (PH) or myocardial late gadolinium enhancement (LGE) showed a greater reduction in strain compared with those without PH or LGE. GLS showed a negative association with erythrocyte sedimentation rate (ESR), while GCS showed a positive association with disease duration. In the 30 patients who were followed up, the baseline global and apical circumferential diastolic peak strain rates (DPSR) in patients with reduced LVEF were higher than those in patients without reduced LVEF.

Conclusions

In patients with TAK and pLVEF, CMR-FT indicated that both global and segmental myocardial strain decreased. PH, male gender, long disease duration, elevated ESR, and myocardial LGE were associated with declined LV strain. Baseline increased circumferential DPSR may be associated with the decline in LVEF during follow-up.

Comparison of left ventricular global and segmental strain parameters by cardiovascular magnetic resonance tissue tracking in light-chain cardiac amyloidosis and hypertrophic cardiomyopathy

Background

Apical sparing of left ventricular (LV) strain can occur in light-chain cardiac amyloidosis (AL-CA). We employed indicators of the strain ratio of the apex to base (RAB) and the relative apical sparing of strain (RAS) on the basis of LV global and segmental strain to distinguish AL-CA from hypertrophic cardiomyopathy (HCM).

Methods

In all, 36 AL-CA patients, 37 HCM patients, and 36 healthy controls underwent 3.0 T cardiac magnetic resonance (CMR) examination. We compared LV strain parameters from CMR tissue tracking (CMR-TT), including global and segmental peak radial strain (PRS), peak circumferential strain (PCS), and peak longitudinal strain (PLS); the peak systolic strain rate in radial, circumferential, and longitudinal directions (PSSR_R, PSSR_C, PSSR_L); and the peak diastolic strain rate in radial, circumferential, and longitudinal directions (PDSR_R, PDSR_C, PDSR_L). We also assessed the values of RAB and RAS. Differences in all groups were compared using an independent t-test and a nonparametric rank sum test.

Results

In the comparison of global strain parameters, all the peak strain, systolic, and diastolic peak strain rates of the AL-CA group significantly decreased compared with those of the HCM and healthy control groups (all P<0.001). The values of PSSR in all directions were lower in the AL-CA than in the HCM patients (PSSR_R, P<0.001; PSSR_C, P=0.004; PSSR_L, P=0.010) . In the analysis of segmental strain parameters, all peak strains in the basal segment showed significant differences between the AL-CA and HCM groups (all P<0.001). Some strain rate parameters in the basal segment were also noted to be significantly different (PSSR_R, P<0.001; PSSR_L, P<0.001; PDSR_R, P=0.015; PDSR_C, P=0.020). Both the RAB and RAS of peak strain in all directions showed significant differences between the AL-CA and HCM groups (all P<0.001). The RAB of the radial and circumferential PSSR showed statistical differences between the 2 groups (P<0.001 and P=0.001). The RAS in the radial direction of both the PSSR and PDSR was statistically different (P=0.003 and P=0.012).

Conclusions

The CMR-TT technique can be used to quantitatively compare global and segmental strain differences between AL-CA and HCM. In addition, RAB and RAS are reliable parameters for assessing the apical sparing pattern and thus, for distinguishing AL-CA from HCM.

Diagnostic performance of cardiac magnetic resonance segmental myocardial strain for detecting microvascular obstruction and late gadolinium enhancement in patients presenting after a ST-elevation myocardial infarction

Background

Microvascular obstruction (MVO) and Late Gadolinium Enhancement (LGE) assessed in cardiac magnetic resonance (CMR) are associated with adverse outcome in patients with ST-elevation myocardial infarction (STEMI). Our aim was to analyze the diagnostic performance of segmental strain for the detection of MVO and LGE.

Methods

Patients with anterior STEMI, who underwent additional CMR were enrolled in this sub-study of the CARE-AMI trial. Using CMR feature tracking (FT) segmental circumferential peak strain (SCS) was measured and the diagnostic performance of SCS to discriminate MVO and LGE was assessed in a derivation and validation cohort.

Results

Forty-eight STEMI patients (62 ± 12 years old), 39 (81%) males, who underwent CMR (i.e., mean 3.0 ± 1.5 days) after primary percutaneous coronary intervention (PCI) were included. All patients presented with LGE and in 40 (83%) patients, MVO was additionally present. Segments in all patients were visually classified and 146 (19%) segments showed MVO (i.e., LGE+/MVO+), 308 (40%) segments showed LGE and no MVO (i.e., LGE+/MVO–), and 314 (41%) segments showed no LGE (i.e., LGE–). Diagnostic performance of SCS for detecting MVO segments (i.e., LGE+/MVO+ vs. LGE+/MVO–, and LGE–) showed an AUC = 0.764 and SCS cut-off value was –11.2%, resulting in a sensitivity of 78% and a specificity of 67% with a positive predictive value (PPV) of 30% and a negative predictive value (NPV) of 94% when tested in the validation group. For LGE segments (i.e., LGE+/MVO+ and LGE+/MVO– vs. LGE–) AUC = 0.848 and SCS with a cut-off value of –13.8% yielded to a sensitivity of 76%, specificity of 74%, PPV of 81%, and NPV of 70%.

Conclusion

Segmental strain in STEMI patients was associated with good diagnostic performance for detection of MVO+ segments and very good diagnostic performance of LGE+ segments. Segmental strain may be useful as a potential contrast-free surrogate marker to improve early risk stratification in patients after primary PCI.

Quantification of strain analysis and late gadolinium enhancement in coronary chronic total occlusion: a cardiovascular magnetic resonance imaging follow-up study

Background

The present study aimed to investigate the benefits of percutaneous coronary intervention (PCI) in patients with chronic total occlusions (CTOs) by using cardiac magnetic resonance imaging (CMR) feature tracking.

Methods

Fifty-five CTOs with successful CTO-PCI underwent CMR at baseline and 12 months. Feature tracking was applied to measure left ventricle strain index in CTOs with decreased and preserved left ventricular ejection fraction (LVEF). CTOs were also divided into two groups according to the infarct size of 10% or combined with multi-vessel disease. We also measured these parameters in 40 healthy subjects.

Results

Three quarters of CTOs showed preserved ejection fraction and no enlargement of left ventricle at baseline, but the global strains were lower than the controls (all P<0.01). In the entire CTO population, left ventricular ejection fraction did not show significant improvement in the 1-year follow-up (59.8%±11.3% vs. 62.0%±8.6%, P=0.08). However, global strains improved over time, and peak global radial strain and circumferential strain showed significant treatment effect of CTO-PCI in the entire CTO population (31.1%±9.9% vs. 34.3%±8.7%, P<0.01; -17.9±3.6 vs. -19.2±3.1, P<0.01), and the subgroup with decreased LVEF, infarct size less than 10%, or multi-vessel disease, but not with the 1-vessel disease. In the LAD and LCX CTO territory, radial and circumferential strain showed treatment effect of CTO-PCI on the recovery of strain parameters (P<0.01 for both). In the RCA CTO territory, circumferential and longitudinal strain showed treatment effect of CTO-PCI on the recovery of strain parameters (P<0.05 for both).

Conclusions

In this single center study, global radial strain and circumferential strain showed treatment effect of successful CTO-PCI at 1-year follow-up in CTOs with the decreased LVEF, infarct size less than 10%, or multi-vessel disease, and the regional strain also showed a similar trend. However, the benefit of CTO-PCI on the strain recovery was not shown in patients with 1-vessel disease. Therefore, whether patients with CTO benefit from PCI still needs further verification.

Characterization and clinical significance of biventricular mechanics in patients with systemic lupus erythematosus by 3T cardiovascular magnetic resonance tissue tracking

BACKGROUND

Detecting impaired left ventricle (LV) or right ventricle (RV) mechanics could aid in fully understanding the process of cardiac involvement in patients with systemic lupus erythematosus (SLE). This study aimed to evaluate biventricular strain parameters derived from cardiac magnetic resonance (CMR) tissue tracking in SLE patients and their association with other clinical variables.

METHODS

A group of 47 SLE patients and 27 healthy controls were enrolled and underwent CMR examination, including cine and late gadolinium enhancement (LGE) imaging. Aside from RV strain parameters in the radial direction, biventricular global peak strain and peak systolic/diastolic global strain rate in radial, circumferential, and longitudinal directions were assessed for each participant. Multivariate linear regression analysis was used to analyze the factors related to the biventricular strain parameters. Receiver operating characteristic (ROC) analysis was used to identify RV dysfunction.

RESULTS

Compared with the controls, part of the biventricular strain parameters in the SLE subgroup with preserved ejection fraction (EF) were impaired, which was more significant in the SLE subgroup with reduced EF (all P<0.05). The SLE patients with RV dysfunction (15/47) included patients with LV dysfunction (8/47). The RVEF was associated with impaired LV global peak strain and peak diastolic strain rate in the SLE patients (absolute value of β=0.406-0.715, all P<0.05). The LV LGE in SLE patients (12/47) was associated with LV global longitudinal peak strain and peak diastolic global longitudinal strain rate (β=0.378 and -0.342; all P<0.05). There were independent correlations between pulmonary arterial hypertension and RV global longitudinal peak strain, anti-ribonucleoprotein (RNP) antibody and RV global circumferential peak strain, and pericardial effusion and RV peak diastolic global circumferential strain rate, respectively (β=0.319, 0.359, and -0.285, respectively; all P<0.05). The LV global longitudinal peak strain had greater diagnostic accuracy for RV dysfunction RV dysfunction [area under curve (AUC): 0.933, cut-off value: -13.38%).

CONCLUSIONS

Biventricular strain parameters derived from CMR are sensitive markers of subclinical ventricular function impairment before EF reduction at an early stage of SLE. Biventricular strain analysis could be considered for inclusion in early cardiac functional assessment in SLE patients, particularly LV global longitudinal peak strain, which might assist in therapeutic decision-making and disease monitoring.

CCTA-derived strain analysis in detection of regional myocardial dysfunction in coronary artery disease patients with preserved left ventricular ejection fraction: A feasibility study

OBJECTIVES

To evaluate the feasibility of using coronary computed tomography angiography (CCTA)-derived strain to detect regional myocardial dysfunction in coronary artery disease (CAD) patients with normal left ventricular ejection fraction (LVEF).

METHODS

A total of 1,580 segments from 101 patients who underwent stressed CT myocardial perfusion imaging (CT-MPI) and CCTA were retrospectively enrolled in this study. The CT-derived global and segmental strain values were evaluated using the feature tracking technique. Segments with myocardial blood flow (MBF) < 125 ml/min/100 ml and 95 ml/min/100 ml were categorized as ischemic and infarcted, respectively.

RESULTS

Segmental radial strain (SRS) and segmental circumferential strain (SCS) in the abnormal segments (including all segments with MBF < 125 ml/min/100 ml) were significantly lower than those in the normal segments (14.81±8.65% vs 17.17±9.13%, p < 0.001; -10.21±5.79% vs -11.86±4.52%, p < 0.001, respectively). SRS and SCS values in infarcted segments were significantly impaired compared with the ischemic segments (12.43±8.03% vs. 15.32±8.71%, p = 0.038; -7.72±5.91% vs. -10.67±5.66%, p = 0.010, respectively). The AUCs for SRS and SCS in detecting infarcted segments were 0.622 and 0.698, respectively (p < 0.05).

CONCLUSIONS

It is feasible for using CCTA-derived strain parameters to detect regional myocardial dysfunction in CAD patients with preserved LVEF. Segmental radial and circumferential strain have the potential ability to distinguish myocardial ischemia from infarction, and normal from ischemic myocardium.

Quantitative Assessment of Left and Right Atrial Strains Using Cardiovascular Magnetic Resonance Based Tissue Tracking

Background: Left and right atrium (LA and RA) exert an essential and dynamic role in ventricular filling and hence affect heart performance. Strain quantification has been reported as a novel parameter to assess function. However, the assessment of bi-atrial strains with cardiovascular magnetic resonance (CMR) based techniques is still limited and gender- and age-specific normal values in a healthy population are missing.

Methods: One hundred and fifty healthy volunteers (49.8 ± 17.3 years, 75 males) undergoing 1.5 Tesla CMR examination were retrospectively and consecutively recruited. LA and RA free wall (RAFW) radial and longitudinal strains (RS and LS) associated with atrial reservoir, conduit and booster pump functions were evaluated with CMR based tissue tracking (CMR-TT) technique.

Results: The reservoir, conduit and pump LS resulted as 30.7 ± 10.2%, 19.5 ± 8.2%, 10.9 ± 3.7% for LA, and 52.2 ± 17.6%, 33.3 ± 14.2%, 19.1 ± 8.5% for RAFW, respectively. The amplitude of RA strains was significantly larger than that of LA strains, except for conduit RS. With the increase of age, the decrement of majority of reservoir and conduit strains were observed, while pump strains remained unaffected. Females presented with significantly larger RAFW strains compared with males, especially in the elderly. In addition to the positive correlation between atrial strains and emptying fraction, the negative correlation between atrial strains and volume index was also confirmed. Intra-observer reproducibility of LA strains was superior to RAFW strains (coefficient of variation: 10.12–17.04% vs. 10.80–27.36%, respectively), and the measurement of reservoir and conduit strains was more reproducible in comparison with pump strain.

Conclusion: CMR-TT is a feasible and reproducible technique to quantify LA and RA strains and determine atrial phasic functions. The existence of age- and gender-related difference of strains suggests the necessity to establish specific normal values for individual populations.