Left ventricular myocardial deformation in Takotsubo syndrome: a cardiovascular magnetic resonance myocardial feature tracking study

Prognostic role of cardiovascular magnetic resonance in Takotsubo syndrome: A systematic review

BACKGROUND

Takotsubo syndrome (TS) is characterized by transient myocardial dysfunction with outcomes ranging from favorable to life-threatening. Cardiovascular magnetic resonance (CMR) has emerged as an essential tool in its diagnosis and management and is consistently recommended by current guidelines in the diagnostic work-up. However, the prognostic value of CMR in patients with TS remains undetermined. The aim of this study was to assess the prognostic value of CMR in managing patients with TS.

METHOD

PubMed, MEDLINE via Ovid, Scopus, and the Cochrane Library were searched to identify studies reporting the prognostic role of multiparameteric CMR in patients with TS with a follow-up ≥ 12 months. The primary endpoint was major adverse cardiovascular and cerebrovascular events (MACCE), defined as all-cause mortality, cardiac death, heart failure, sudden cardiac death, recurrence of TS, and cerebrovascular events.

RESULTS

Five studies with 564 patients were included for reporting correlation of CMR parameters with MACCE. Primary endpoint occurred in 69 (12%) patients. Among the CMR parameters assessed, myocardial strain parameters (including measurements of the left atrium, left and right ventricle), right ventricle involvement, and a CMR-based radiomics model demonstrated correlations with MACCE. Additionally, one study showed the predictive ability of a CMR score.

CONCLUSION

The current systematic review suggests that CMR may offer prognostic insights in TS patients, underscoring its potential clinical utility for integration into clinical practice. However, scarce data are currently available; hence, further research is needed.

Base-to-apex Gradient Pattern Assessed by Cardiovascular Magnetic Resonance in Takotsubo Cardiomyopathy

OBJECTIVES

The purpose of this study was to investigate the base-to-apex gradient strain pattern as a noncontrast cardiovascular magnetic resonance (CMR) parameter in patients with Takotsubo cardiomyopathy (TTC) and determine whether this pattern may help discriminate TTC from patients with anterior myocardial infarction (AMI).

MATERIALS AND METHODS

A total of 80 patients were included in the analysis: 30 patients with apical ballooning TTC and 50 patients with AMI. Global and regional ventricular function, including longitudinal (LS), circumferential (CS), and radial strain (RS), were assessed using CMR. The base-to-apex LS, RS, and CS gradients, defined as the peak gradient difference between averaged basal and apical strain, were calculated.

RESULTS

The base-to-apex RS gradient was impaired in TTC patients compared with the AMI group (14.04 ± 15.50 vs. -0.43 ± 11.59, P =0.001). Conversely, there were no significant differences in the base-to-apex LS and CS gradients between the AMI group and TTC patients (0.14 ± 2.71 vs. -1.5 ± 3.69, P =0.054: -0.99 ± 6.49 vs. ±1.4 ± 5.43, P =0.47, respectively). Beyond the presence and extension of LGE, base-to-apex RS gradient was the only independent discriminator between TTC and AMI (OR 1.28; 95% CI 1.08, 1.52, P =0.006) in multivariate logistic regression analysis.

CONCLUSION

The findings of this study suggest that the pattern of regional myocardial strain impairment could serve as an additional noncontrast CMR tool to refine the diagnosis of TTC. A pronounced base-to-apex RS gradient may be a specific left ventricle strain pattern of TTC.

CMR-based cardiac phenotyping in different forms of heart failure

Heart failure (HF) is a heterogenous disease requiring precise diagnostics and knowledge of pathophysiological processes. Since structural and functional imaging data are scarce we hypothesized that cardiac magnetic resonance (CMR)-based analyses would provide accurate characterization and mechanistic insights into different HF groups comprising preserved (HFpEF), mid-range (HFmrEF) and reduced ejection fraction (HFrEF). 22 HFpEF, 17 HFmrEF and 15 HFrEF patients as well as 19 healthy volunteers were included. CMR image assessment contained left atrial (LA) and left ventricular (LV) volumetric evaluation as well as left atrioventricular coupling index (LACI). Furthermore, CMR feature-tracking included LV and LA strain in terms of reservoir (Es), conduit (Ee) and active boosterpump (Ea) function. CMR-based tissue characterization comprised T1 mapping as well as late-gadolinium enhancement (LGE) analyses. HFpEF patients showed predominant atrial impairment (Es 20.8%vs.25.4%, p = 0.02 and Ee 8.3%vs.13.5%, p = 0.001) and increased LACI compared to healthy controls (14.5%vs.23.3%, p = 0.004). Patients with HFmrEF showed LV enlargement but mostly preserved LA function with a compensatory increase in LA boosterpump (LA Ea: 15.0%, p = 0.049). In HFrEF LA and LV functional impairment was documented (Es: 14.2%, Ee: 5.4% p < 0.001 respectively; Ea: 8.8%, p = 0.02). This was paralleled by non-invasively assessed progressive fibrosis (T1 mapping and LGE; HFrEF > HFmrEF > HFpEF). CMR-imaging reveals insights into HF phenotypes with mainly atrial affection in HFpEF, ventricular affection with atrial compensation in HFmrEF and global impairment in HFrEF paralleled by progressive LV fibrosis. These data suggest a necessity for a personalized HF management based on imaging findings for future optimized patient management.

Time Course of Left Ventricular Strain Assessment via Cardiovascular Magnetic Resonance Myocardial Feature Tracking in Takotsubo Syndrome

Background: Although takotsubo syndrome (TTS) is characterized by transient systolic dysfunction of the left ventricle (LV), the time course and mechanism of LV function recovery remain elusive. The aim of this study is to evaluate cardiac functional recovery in TTS via serial cardiac magnetic resonance feature tracking (CMR-FT). Methods: In this Japanese multicenter registry, patients with newly diagnosed TTS were prospectively enrolled. In patients who underwent serial cardiovascular magnetic resonance (CMR) imaging at 1 month and 1 year after the onset, CMR-FT was performed to determine the global circumferential strain (GCS), global radial strain (GRS) and global longitudinal strain (GLS). We compared LV ejection fraction, GCS, GRS and GLS at 1 month and 1 year after the onset of TTS. Results: Eighteen patients underwent CMR imaging in one month and one year after the onset in the present study. LV ejection fraction had already normalized at 1 month after the onset, with no significant difference between 1 month and 1 year (55.8 ± 9.2% vs. 58.9 ± 7.3%, p = 0.09). CMR-FT demonstrated significant improvement in GCS from 1 month to 1 year (-16.7 ± 3.4% vs. -18.5 ± 3.2%, p < 0.01), while there was no significant difference in GRS and GLS between 1 month and year (GRS: 59.6 ± 24.2% vs. 59.4 ± 17.3%, p = 0.95, GLS: -12.8 ± 5.9% vs. -13.8 ± 4.9%, p = 0.42). Conclusions: Serial CMR-FT analysis revealed delayed improvement of GCS compared to GRS and GLS despite of rapid recovery of LV ejection fraction. CMR-FT can detect subtle impairment of LV systolic function during the recovery process in patients with TTS.

Impact of myocardial deformation on risk prediction in patients following acute myocardial infarction

Background

Strain analyses derived from cardiovascular magnetic resonance-feature tracking (CMR-FT) provide incremental prognostic benefit in patients sufferring from acute myocardial infarction (AMI). This study aims to evaluate and revalidate previously reported prognostic implications of comprehensive strain analyses in a large independent cohort of patients with ST-elevation myocardial infarction (STEMI).

Methods

Overall, 566 STEMI patients enrolled in the CONDITIONING-LIPSIA trial including pre- and/or postconditioning treatment in addition to conventional percutaneous coronary intervention underwent CMR imaging in median 3 days after primary percutaneous coronary intervention. CMR-based left atrial (LA) reservoir (Es), conduit (Ee), and boosterpump (Ea) strain analyses, as well as left ventricular (LV) global longitudinal strain (GLS), circumferential strain (GCS), and radial strain (GRS) analyses were carried out. Previously identified cutoff values were revalidated for risk stratification. Major adverse cardiac events (MACE) comprising death, reinfarction, and new congestive heart failure were assessed within 12 months after the occurrence of the index event.

Results

Both atrial and ventricular strain values were significantly reduced in patients with MACE (p < 0.01 for all). Predetermined LA and LV strain cutoffs enabled accurate risk assessment. All LA and LV strain values were associated with MACE on univariable regression modeling (p < 0.001 for all), with LA Es emerging as an independent predictor of MACE on multivariable regression modeling (HR 0.92, p = 0.033). Furthermore, LA Es provided an incremental prognostic value above LVEF (a c-index increase from 0.7 to 0.74, p = 0.03).

Conclusion

External validation of CMR-FT-derived LA and LV strain evaluations confirmed the prognostic value of cardiac deformation assessment in STEMI patients. In the present study, LA strain parameters especially enabled further risk stratification and prognostic assessment over and above clinically established risk parameters.

Clinical Trial Registration

ClinicalTrials.gov, identifier NCT02158468.

Strain Echocardiography in Acute COVID-19 and Post-COVID Syndrome: More than Just a Snapshot

Speckle-tracking echocardiography (STE) has become an established, widely available diagnostic method in the past few years, making its value clear in cases of COVID-19 and the further course of the disease, including post-COVID syndrome. Since the beginning of the pandemic, many studies have been published on the use of STE in this condition, enabling, on the one hand, a better understanding of myocardial involvement in COVID-19 and, on the other, a better identification of risk to patients, although some questions remain unanswered in regard to specific pathomechanisms, especially in post-COVID patients. This review takes a closer look at current findings and potential future developments by summarising the extant data on the use of STE, with a focus on left and right ventricular longitudinal strain.

Machine learning approach in diagnosing Takotsubo cardiomyopathy: The role of the combined evaluation of atrial and ventricular strain, and parametric mapping

BACKGROUND

Cardiac magnetic resonance (CMR) with late gadolinium enhancement (LGE) is a key diagnostic tool in the differential diagnosis between non-ischemic cause of cardiac chest pain. Some patients are not eligible for a gadolinium contrast-enhanced CMR; in this scenario, the diagnosis remains challenging without invasive examination. Our purpose was to derive a machine learning model integrating some non-contrast CMR parameters and demographic factors to identify Takotsubo cardiomyopathy (TTC) in subjects with cardiac chest pain.

MATERIAL AND METHODS

Three groups of patients were retrospectively studied: TTC, acute myocarditis, and healthy controls. Global and regional left ventricular longitudinal, circumferential, and radial strain (RS) analysis included were assessed. Reservoir, conduit, and booster bi-atrial functions were evaluated by tissue-tracking. Parametric mapping values were also assessed in all the patients. Five different tree-based ensemble learning algorithms were tested concerning their ability in recognizing TTC in a fully cross-validated framework.

RESULTS

The CMR-based machine learning (ML) ensemble model, by using the Extremely Randomized Trees algorithm with Elastic Net feature selection, showed a sensitivity of 92% (95% CI 78-100), specificity of 86% (95% CI 80-92) and area under the ROC of 0.94 (95% CI 0.90-0.99) in diagnosing TTC. Among non-contrast CMR parameters, the Shapley additive explanations analysis revealed that left atrial (LA) strain and strain rate were the top imaging markers in identifying TTC patients.

CONCLUSIONS

Our study demonstrated that using a tree-based ensemble learning algorithm on non-contrast CMR parameters and demographic factors enables the identification of subjects with TTC with good diagnostic accuracy.

TRANSLATIONAL OUTLOOK

Our results suggest that non-contrast CMR features can be implemented in a ML model to accurately identify TTC subjects. This model could be a valuable tool for aiding in the diagnosis of subjects with a contraindication to the contrast media. Furthermore, the left atrial conduit strain and strain rate were imaging markers that had a strong impact on TTC identification. Further prospective and longitudinal studies are needed to validate these findings and assess predictive performance in different cohorts, such as those with different ethnicities, and social backgrounds and undergoing different treatments.

[MINOCA-myocardial infarction with nonobstructive coronary arteries]

BACKGROUND

Myocardial infarction with nonobstructive coronary arteries (MINOCA) accounts for 5-10% of all presentations of acute myocardial infarction.

OBJECTIVES

To outline the role of cardiovascular magnetic resonance (CMR) in patients with suspected MINOCA.

MATERIALS AND METHODS

Current guidelines for the use of CMR in suspected MINOCA are summarized. Clinical cases with typical CMR findings are presented.

RESULTS

In 2019, the American Heart Association published a revised definition of the term MINOCA, which was recently adopted in the European Society of Cardiology 2020 guidelines on acute coronary syndromes without persistent ST-segment elevation (NSTE-ACS). The guidelines indicate that a CMR is recommended (class 1B) in all MINOCA cases with no obvious cause.

CONCLUSION

The major strength of CMR imaging is to differentiate nonischemic from ischemic etiologies of myocardial injury. This makes CMR the most important noninvasive diagnostic tool for the differential diagnosis of patients with suspected MINOCA.

Artificial intelligence fully automated myocardial strain quantification for risk stratification following acute myocardial infarction

Feasibility of automated volume-derived cardiac functional evaluation has successfully been demonstrated using cardiovascular magnetic resonance (CMR) imaging. Notwithstanding, strain assessment has proven incremental value for cardiovascular risk stratification. Since introduction of deformation imaging to clinical practice has been complicated by time-consuming post-processing, we sought to investigate automation respectively. CMR data (n = 1095 patients) from two prospectively recruited acute myocardial infarction (AMI) populations with ST-elevation (STEMI) (AIDA STEMI n = 759) and non-STEMI (TATORT-NSTEMI n = 336) were analysed fully automated and manually on conventional cine sequences. LV function assessment included global longitudinal, circumferential, and radial strains (GLS/GCS/GRS). Agreements were assessed between automated and manual strain assessments. The former were assessed for major adverse cardiac event (MACE) prediction within 12 months following AMI. Manually and automated derived GLS showed the best and excellent agreement with an intraclass correlation coefficient (ICC) of 0.81. Agreement was good for GCS and poor for GRS. Amongst automated analyses, GLS (HR 1.12, 95% CI 1.08-1.16, p < 0.001) and GCS (HR 1.07, 95% CI 1.05-1.10, p < 0.001) best predicted MACE with similar diagnostic accuracy compared to manual analyses; area under the curve (AUC) for GLS (auto 0.691 vs. manual 0.693, p = 0.801) and GCS (auto 0.668 vs. manual 0.686, p = 0.425). Amongst automated functional analyses, GLS was the only independent predictor of MACE in multivariate analyses (HR 1.10, 95% CI 1.04-1.15, p < 0.001). Considering high agreement of automated GLS and equally high accuracy for risk prediction compared to the reference standard of manual analyses, automation may improve efficiency and aid in clinical routine implementation.Trial registration: ClinicalTrials.gov, NCT00712101 and NCT01612312.

Atrial Impairment as a Marker in Discriminating Between Takotsubo and Acute Myocarditis Using Cardiac Magnetic Resonance

PURPOSE

The purpose of this study was to comprehensively compare the left and right atrium strain and strain rate (SR) parameters by cardiac magnetic resonance (CMR) between patients with Takotsubo (TS) and patients with acute myocarditis (AM).

MATERIALS AND METHODS

We retrospectively enrolled 3 groups of patients: TS (n=18), AM (n=14), and 11 healthy subjects. All the patients had complete CMR data for features tracking assessment.Differences in reservoir, conduit strain (εe), conduit strain rate (SRe), and booster phase of biatrial strain were analyzed between the groups using analysis of variance and multivariate analysis of covariance analyses. Intraobserver and interobserver reproducibility was assessed for all strain and SR parameters using intraclass correlation coefficients and Bland-Altman analysis.

RESULTS

Atrial strain was feasible in all patients and controls. In TS, left atrium (LA) reservoir strain (εs), reservoir SR, εe, and SRe were significantly lower compared with the other groups (P=0,001 for all). multivariate analysis of covariance analysis showed association of these parameters after correction for age and sex, while LA booster deformation (εa and SRa) strain parameters were preserved. LA SRe proved to have excellent sensitivity in differentiating patients with TS from those with AM (areas under the curves of 0.903, 95% confidence interval: 0.81-0.99).Biatrial strain and SR parameters showed good (excellent) intraobserver and interobserver reproducibility (ranged between 0.61 to 0.96 and 0.50 to 0.90, respectively).

CONCLUSION

Compared with AM, patients with TS showed significantly decreased LA reservoir, conduit strain, and SR parameters. Therefore, LA strain assessment may have a role in discriminating between TS and AM.

Cardiovascular Imaging in Stress Cardiomyopathy (Takotsubo Syndrome)

Stress cardiomyopathy (Takotsubo syndrome) is a reversible syndrome stemming from myocardial injury leading to systolic dysfunction and is usually noted in the setting of a stressful event, be it an emotional or physical trigger. While the exact pathophysiology behind stress cardiomyopathy is yet unknown, there is ample evidence suggesting that neurocardiogenic mechanisms may play an important role. Although historically stress cardiomyopathy was generally thought to be a relatively benign condition, there is growing recognition of the cardiovascular complications associated with it despite its reversibility. Our review aims to shed light onto key cardiovascular imaging modalities used to diagnose stress cardiomyopathy while highlighting the role that imaging plays in assessing disease severity, identifying complications, dictating treatment approaches, and in short-term and long-term prognosis.

Stepwise approach for diagnosis and management of Takotsubo syndrome with cardiac imaging tools

Takotsubo syndrome is featured by transient left ventricle dysfunction in the absence of significant coronary artery disease, mainly triggered by emotional or physical stress. Its clinical presentation is similar to acute coronary syndrome; therefore, cardiac imaging tools have a crucial role. Coronary angiography is mandatory for exclusion of pathological stenosis. On the other side, transthoracic echocardiography is the first non-invasive imaging modality for an early evaluation of left ventricle systolic and diastolic function. Left ventricle morphologic patterns could be identified according to the localization of wall motion abnormalities. Moreover, an early identification of potential mechanical and electrical complications such as left ventricle outflow tract obstruction, mitral regurgitation, thrombus formation, right ventricular involvement, cardiac rupture, and cardiac rhythm disorders could provide additional information for clinical management and therapy. Because of the dynamic evolution of the syndrome, comprehensive serial echocardiographic examinations should be systematically performed. Advanced techniques, including speckle-tracking echocardiography, cardiac magnetic resonance, and nuclear imaging can provide mechanistic and pathophysiologic insights into this syndrome. This review focuses on these aspects and provide a stepwise approach of all cardiac imaging tools for the diagnosis and the management of Takotsubo syndrome.

What Is Normal for an Aging Heart?: A Prospective CMR Cohort Study

BACKGROUND

This study aims to investigate normal changes throughout aging of the heart in cardiac magnetic resonance (CMR) imaging in healthy volunteers. While type 2 diabetes mellitus is a frequent finding in the elderly population, also the influence of this circumstance in otherwise healthy persons is part of our study.

METHODS

In this prospective single-center trial, 75 healthy subjects in distinct age groups and 10 otherwise healthy diabetics were enrolled. All subjects underwent functional, flow sensitive, native T2- and T1-mapping in a 1.5T CMR scanner.

RESULTS

No differences in right and left ventricular ejection fractions were observed between aging healthy groups. Bi-ventricular volumes lowered significantly (p<0.001) between the age groups. There was also a significant decrease in myocardial T1 values, aortic distensibility, and left ventricular peak diastolic strain rates. There were no differences in T2 mapping and the other deformation parameters. Patients with type 2 diabetes mellitus had lower end-diastolic volume indexes; all the other measurements were comparable.

CONCLUSIONS

Aging processes in the healthy heart involve a decrease in ventricular volumes, with ejection fractions remaining normal. Stiffening of the myocardium and aorta and a decrease in T1 values are potential indications of age-related remodeling. Type 2 diabetes mellitus seems to have no major influence on aging processes of the heart.

Trial Registration

EudraCT Identifier: EudraCT 2017-000045-42

Review of multi-modality imaging update and diagnostic work up of Takotsubo cardiomyopathy

Takotsubo cardiomyopathy (TC) is an acute but reversible non-ischemic heart failure syndrome. It is characterized by a transient form of ventricular dysfunction typically manifesting as basal hyperkinesis with hypokinesia and ballooning of left ventricle mid-cavity and apex. Imaging helps in both diagnosis and follow up. Echocardiogram is the first-line modality to assess the typical contractile dysfunction in suspected patients with catheter angiography showing normal coronary arteries. Cardiac MRI is currently the modality of choice for the non-invasive initial assessment of TC and for follow up imaging. The current review focusses on historical background of TC, its pathophysiology, diagnostic work up and differential diagnosis and provides multimodality imaging work up of TC including role of echocardiogram, invasive catheterization, nuclear imaging, cardiac computed tomography and cardiac MRI including basic and advanced MRI sequences.

Novel Imaging and Genetic Risk Markers in Takotsubo Syndrome

Takotsubo syndrome (TTS) is an increasingly recognized condition burdened by significant acute and long-term adverse events. The availability of novel techniques expanded the knowledge on TTS and allowed a more accurate risk-stratification, potentially guiding clinical management. The present review aims to summarize the recent advances in TTS prognostic evaluation with a specific focus on novel imaging and genetic markers. Parametric deformation analysis by speckle-tracking echocardiography, as well as tissue characterization by cardiac magnetic resonance imaging T1 and T2 mapping techniques, currently appear the most clinically valuable applications. Notwithstanding, computed tomography and nuclear imaging studies provided limited but promising data. A genetic predisposition to TTS has been hypothesized, though available evidence is still not sufficient. Although a genetic predisposition appears likely, further studies are needed to fully characterize the genetic background of TTS, in order to identify genetic markers that could assist in predicting disease recurrences and help in familial screening.

Impact of residual thrombus burden on ventricular deformation after acute myocardial infarction: A sub-analysis from an intravascular optical coherence tomography study

BACKGROUND

Coronary residual thrombus before stenting in ST-segment elevation myocardial infarction (STEMI) has been linked to microvascular injury but its impact on ventricular deformation and cardiac dysfunction in longer term remains unclear.

METHODS

This was a post-hoc sub-analysis from an optical coherence tomography registry. Residual thrombus before stenting was measured geometrically and maximal thrombus-to-lumen area ratio (MTR) was reported. Cardiovascular magnetic resonance (CMR) follow-ups were performed at 30 days post STEMI. The primary outcomes were CMR-derived parameters including left ventricular ejection fraction (LVEF), infarct size, microvascular obstruction (MVO), and left ventricular global strains in radial (GRS), circumferential (GCS), longitudinal (GLS) directions.

FINDINGS

From March 2017 to March 2019, forty-two patients with first-ever anterior STEMI were included. Average CMR follow-up time was 33 (IQR 30-37) days. In multivariable analysis, MTR was significantly associated with LVEF (per 10%, adjusted β = -1·96, 95%CI -3·66 to -0·26), MVO (per 10%, adjusted β = 0·07, 95%CI 0·01 to 0·13), GRS (per 10%, adjusted β = -1·26, 95%CI -2·28 to -0·23), and GCS (per 10%, adjusted β = 0·53, 95%CI 0·01 to 1·06). However, it was not related to GLS (per 10%, adjusted β = 0·29, 95%CI -0·85 to 1·43) or infarct size (per 10%, adjusted β = 0·07, 95%CI -0·40 to 0·55).

INTERPRETATION

Larger residual thrombus burden was associated with worse GRS and GCS but not GLS after a first anterior myocardial infarction.

FUNDING

This work was supported by Chinese Academy of Medical Sciences Innovation Fund for Medical Sciences (2016-I2M-1-009), National Natural Science Foundation of China (81,970,308, 81,930,044, and 81,620,108,015), Sanming Project of Medicine in Shenzhen (SZSM201911017), and Shenzhen Key Medical Discipline Construction Fund (No. SZXK001).

Takotsubo Syndrome-Is There a Need for CMR?

PURPOSE OF REVIEW

Takotsubo syndrome (TTS) is a transient but severe myocardial dysfunction that has been known for decades and is still to be fully understood regarding its clinical presentations and pathophysiological mechanisms. Cardiac magnetic resonance (CMR) imaging plays a key role in the comprehensive analysis of patients with TTS in acute and follow-up examinations. In this review, we focus on the major advantages and latest evolutions of CMR in diagnosis and prognostication of TTS and discuss future perspectives and needs in the field of research and cardiovascular imaging in TTS.

RECENT FINDINGS

Specific CMR criteria for TTS diagnosis at the time of acute presentation are established. In addition to identifying the typical regional wall motion abnormalities, CMR allows for precise quantification of right ventricular and left ventricular (LV) function, the assessment of additional abnormalities/complications (e.g. pericardial and/or pleural effusion, LV thrombi), and most importantly myocardial tissue characterization (myocardial oedema, inflammation, necrosis/fibrosis). CMR enables a comprehensive assessment of the entire spectrum of functional and structural changes that occur in patients with TTS and may have also a prognostic impact. CMR can distinguish between TTS and other important differential diagnoses (myocarditis, myocardial infarction) with direct consequences on medical therapy.

Quantification of Myocardial Deformation Applying CMR-Feature-Tracking-All About the Left Ventricle?

Purpose of Review

Cardiac magnetic resonance-feature-tracking (CMR-FT)-based deformation analyses are key tools of cardiovascular imaging and applications in heart failure (HF) diagnostics are expanding. In this review, we outline the current range of application with diagnostic and prognostic implications and provide perspectives on future trends of this technique.

Recent Findings

By applying CMR-FT in different cardiovascular diseases, increasing evidence proves CMR-FT-derived parameters as powerful diagnostic and prognostic imaging biomarkers within the HF continuum partly outperforming traditional clinical values like left ventricular ejection fraction. Importantly, HF diagnostics and deformation analyses by CMR-FT are feasible far beyond sole left ventricular performance evaluation underlining the holistic nature and accuracy of this imaging approach.

Summary

As an established and continuously evolving technique with strong prognostic implications, CMR-FT deformation analyses enable comprehensive cardiac performance quantification of all cardiac chambers.

Multimodality imaging in takotsubo syndrome: a joint consensus document of the European Association of Cardiovascular Imaging (EACVI) and the Japanese Society of Echocardiography (JSE)

Takotsubo syndrome (TTS) is a complex and still poorly recognized heart disease with a wide spectrum of possible clinical presentations. Despite its reversibility, it is associated with serious adverse in-hospital events and high complication rates during follow-up. Multimodality imaging is helpful for establishing the diagnosis, guiding therapy, and stratifying prognosis of TTS patients in both the acute and post-acute phase. Echocardiography plays a key role, particularly in the acute care setting, allowing for the assessment of left ventricular (LV) systolic and diastolic function and the identification of the typical apical-midventricular ballooning pattern, as well as the circumferential pattern of wall motion abnormalities. It is also useful in the early detection of complications (i.e. LV outflow tract obstruction, mitral regurgitation, right ventricular involvement, LV thrombi, and pericardial effusion) and monitoring of systolic function recovery. Left ventriculography allows the evaluation of LV function and morphology, identifying the typical TTS patterns when echocardiography is not available or wall motion abnormalities cannot be properly assessed with ultrasound. Cardiac magnetic resonance provides a more comprehensive depiction of cardiac morphology and function and tissue characterization and offers additional value to other imaging modalities for differential diagnosis (myocardial infarction and myocarditis). Coronary computed tomography angiography has a substantial role in the diagnostic workup of patients with acute chest pain and a doubtful TTS diagnosis to rule out other medical conditions. It can be considered as a non-invasive appropriate alternative to coronary angiography in several clinical scenarios. Although the role of nuclear imaging in TTS has not yet been well established, the combination of perfusion and metabolic imaging may provide useful information on myocardial function in both the acute and post-acute phase.

Prognostic Value of Different CMR-Based Techniques to Assess Left Ventricular Myocardial Strain in Takotsubo Syndrome

Cardiac magnetic resonance (CMR)-derived left ventricular (LV) global longitudinal strain (GLS) provides incremental prognostic information on various cardiovascular diseases but has not yet been investigated comprehensively in patients with Takotsubo syndrome (TS). This study evaluated the prognostic value of feature tracking (FT) GLS, tissue tracking (TT) GLS, and fast manual long axis strain (LAS) in 147 patients with TS, who underwent CMR at a median of 2 days after admission. Long-term mortality was assessed 3 years after the acute event. In contrast to LV ejection fraction and tissue characteristics, impaired FT-GLS, TT-GLS and fast manual LAS were associated with adverse outcome. The best cutoff points for the prediction of long-term mortality were similar with all three approaches: FT-GLS −11.28%, TT-GLS −11.45%, and fast manual LAS −10.86%. Long-term mortality rates were significantly higher in patients with FT-GLS > −11.28% (25.0% versus 9.8%; p = 0.029), TT-GLS > −11.45% (20.0% versus 5.4%; p = 0.016), and LAS > −10.86% (23.3% versus 6.6%; p = 0.014). However, in multivariable analysis, diabetes mellitus (p = 0.001), atrial fibrillation (p = 0.001), malignancy (p = 0.006), and physical triggers (p = 0.006) outperformed measures of myocardial strain and emerged as the strongest, independent predictors of long-term mortality in TS. In conclusion, CMR-based longitudinal strain provides valuable prognostic information in patients with TS, regardless of the utilized technique of assessment. Long-term mortality, however, is mainly determined by comorbidities.

Prognostic value of texture analysis from cardiac magnetic resonance imaging in patients with Takotsubo syndrome: a machine learning based proof-of-principle approach

Cardiac magnetic resonance (CMR) imaging has become an important technique for non-invasive diagnosis of takotsubo syndrome (TTS). The long-term prognostic value of CMR imaging in TTS has not been fully elucidated yet. This study sought to evaluate the prognostic value of texture analysis (TA) based on CMR images in patients with TTS using machine learning. In this multicenter study (InterTAK Registry), we investigated CMR imaging data of 58 patients (56 women, mean age 68 ± 12 years) with TTS. CMR imaging was performed in the acute to subacute phase (median time after symptom onset 4 days) of TTS. TA of the left ventricle was performed using free-hand regions-of-interest in short axis late gadolinium-enhanced and on T2-weighted (T2w) images. A total of 608 TA features adding the parameters age, gender, and body mass index were included. Dimension reduction was performed removing TA features with poor intra-class correlation coefficients (ICC ≤ 0.6) and those being redundant (correlation matrix with Pearson correlation coefficient r > 0.8). Five common machine-learning classifiers (artificial neural network Multilayer Perceptron, decision tree J48, NaïveBayes, RandomForest, and Sequential Minimal Optimization) with tenfold cross-validation were applied to assess 5-year outcome including major adverse cardiac and cerebrovascular events (MACCE). Dimension reduction yielded 10 TA features carrying prognostic information, which were all based on T2w images. The NaïveBayes machine learning classifier showed overall best performance with a sensitivity of 82.9% (confidence interval (CI) 80-86.2), specificity of 83.7% (CI 75.7-92), and an area-under-the receiver operating characteristics curve of 0.88 (CI 0.83-0.92). This proof-of-principle study is the first to identify unique T2w-derived TA features that predict long-term outcome in patients with TTS. These features might serve as imaging prognostic biomarkers in TTS patients.

Functional and prognostic implications of cardiac magnetic resonance feature tracking-derived remote myocardial strain analyses in patients following acute myocardial infarction

Background

Cardiac magnetic resonance myocardial feature tracking (CMR-FT)-derived global strain assessments provide incremental prognostic information in patients following acute myocardial infarction (AMI). Functional analyses of the remote myocardium (RM) are scarce and whether they provide an additional prognostic value in these patients is unknown.

Methods

1034 patients following acute myocardial infarction were included. CMR imaging and strain analyses as well as infarct size quantification were performed after reperfusion by primary percutaneous coronary intervention. The occurrence of major adverse cardiac events (MACE) within 12 months after the index event was defined as primary clinical endpoint.

Results

Patients with MACE had significantly lower RM circumferential strain (CS) compared to those without MACE. A cutoff value for RM CS of − 25.8% best identified high-risk patients (p < 0.001 on log-rank testing) and impaired RM CS was a strong predictor of MACE (HR 1.05, 95% CI 1.07–1.14, p = 0.003). RM CS provided further risk stratification among patients considered at risk according to established CMR parameters for (1) patients with reduced left ventricular ejection fraction (LVEF) ≤ 35% (p = 0.038 on log-rank testing), (2) patients with reduced global circumferential strain (GCS) > −  18.3% (p = 0.015 on log-rank testing), and (3) patients with large microvascular obstruction ≥ 1.46% (p = 0.002 on log-rank testing).

Conclusion

CMR-FT-derived RM CS is a useful parameter to characterize the response of the remote myocardium and allows improved stratification following AMI beyond commonly used parameters, especially of high-risk patients.

Trial registration

ClinicalTrials.gov, NCT00712101 and NCT01612312

Graphic abstract

Defining remote segments (R) in the presence of infarct areas (I) for the analysis of remote circumferential strain (CS). Remote CS was significantly lower in patients who suffered major adverse cardiac events (MACE) and a cutoff value for remote CS of − 25.8% best identified high-risk patients. In addition, impaired remote CS ≥ − 25.8 % (Remote −) and preserved remote CS < − 25.8 % (Remote +) enabled further risk stratification when added to established parameters like left ventricular ejection fraction (LVEF), global circumferential strain (GCS) or microvascular obstruction (MVO).

Myocardial involvement and deformation abnormalities in idiopathic inflammatory myopathy assessed by CMR feature tracking

Background

Cardiac involvement has been described in idiopathic inflammatory myopathies (IIM), including non-specific ECG and echocardiographic findings. Aim of our study was to evaluate myocardial deformation parameters in IIM and to correlate them with late gadolinium enhancement (LGE) findings using cardiac magnetic resonance imaging (CMR).

Methods

Forty-seven consecutive patients with histologically proven IIM were included into our study. Twenty-five healthy volunteers were used as a control group. All patients and controls underwent CMR examination using a 1.5 T scanner including functional cine and LGE imaging. After a mean follow-up of 234.7 ± 79.5 days a second CMR examination was performed in IIM patients.

Results

In comparison to healthy volunteers, IIM patients had lower left ventricular mass and left ventricular global radial, circumferential and longitudinal strain. There was no significant difference in left ventricular ejection fraction.

Patients with LGE (N = 28) had lower left ventricular ejection fraction (p = 0.016), global right and left ventricular longitudinal strain (p = 0.014 and p = 0.005) and global left ventricular diastolic longitudinal strain rate (p = 0.001) compared to patients without LGE (N = 19).

In IIM patients, a significant decrease of left ventricular ejection fraction, left ventricular mass and all measured deformation parameters was observed between baseline and follow-up CMR.

Conclusion

Cardiac involvement in IIM is frequent. Impairment of systolic and diastolic deformation parameters and a worsening over time can be observed. CMR is a useful tool for cardiac diagnostic work-up of these patients.

Multimodality imaging in takotsubo syndrome: a joint consensus document of the European Association of Cardiovascular Imaging (EACVI) and the Japanese Society of Echocardiography (JSE)

Takotsubo syndrome (TTS) is a complex and still poorly recognized heart disease with a wide spectrum of possible clinical presentations. Despite its reversibility, it is associated with serious adverse in-hospital events and high complication rates during follow-up. Multimodality imaging is helpful for establishing the diagnosis, guiding therapy, and stratifying prognosis of TTS patients in both the acute and post-acute phase. Echocardiography plays a key role, particularly in the acute care setting, allowing for the assessment of left ventricular (LV) systolic and diastolic function and the identification of the typical apical-midventricular ballooning pattern, as well as the circumferential pattern of wall motion abnormalities. It is also useful in the early detection of complications (i.e. LV outflow tract obstruction, mitral regurgitation, right ventricular involvement, LV thrombi, and pericardial effusion) and monitoring of systolic function recovery. Left ventriculography allows the evaluation of LV function and morphology, identifying the typical TTS patterns when echocardiography is not available or wall motion abnormalities cannot be properly assessed with ultrasound. Cardiac magnetic resonance provides a more comprehensive depiction of cardiac morphology and function and tissue characterization and offers additional value to other imaging modalities for differential diagnosis (myocardial infarction and myocarditis). Coronary computed tomography angiography has a substantial role in the diagnostic workup of patients with acute chest pain and a doubtful TTS diagnosis to rule out other medical conditions. It can be considered as a non-invasive appropriate alternative to coronary angiography in several clinical scenarios. Although the role of nuclear imaging in TTS has not yet been well established, the combination of perfusion and metabolic imaging may provide useful information on myocardial function in both the acute and post-acute phase.

Advanced cardiac magnetic resonance imaging in takotsubo cardiomyopathy

Takotsubo cardiomyopathy (TC) is a reversible condition in which there is transient left ventricular (LV) dysfunction characterised most commonly by basal hyperkinesis and mid-apical LV ballooning and hypokinesia. It is said to be triggered by stress and mimics, such as acute coronary syndrome (ACS) clinically. Diagnosis is usually suspected on echocardiography due to the characteristic contraction pattern in a patient with symptoms and signs of ACS but normal coronary arteries on catheter angiography. Cardiac magnetic resonance (CMR), with its latest advancements, is the diagnostic modality of choice for diagnosis, prognosis and follow-up of patients. The advances in CMR (including T1, T2, ECV mapping and threshold-based late gadolinium enhancement (LGE) measurements have revolutionised the role of CMR in tissue characterisation and prognostication in patients with TC. In this review, we highlight the current role of CMR in management of TC and enumerate the CMR findings in TC as well the current advances in the field of CMR, which could help in prognosticating these patients.

Mitral annular plane systolic excursion by cardiac MR is an easy tool for optimized prognosis assessment in ST-elevation myocardial infarction

OBJECTIVES

The purpose of this study was to assess the comparative prognostic value of mitral annular plane systolic excursion (MAPSE) versus left ventricular ejection fraction (LVEF), measured by cardiac magnetic resonance (CMR) imaging in patients with ST-elevation myocardial infarction (STEMI) treated with primary percutaneous coronary intervention (pPCI).

METHODS

CMR was performed in 255 STEMI patients within 2 days (interquartile range (IQR) 2-4 days) after infarction. CMR included MAPSE measurement on CINE 4-chamber view. Patients were followed for major adverse cardiovascular events (MACE)-death, non-fatal myocardial re-infarction, stroke, and new congestive heart failure.

RESULTS

Patients with MACE (n = 35, 14%, median follow-up 3 years [IQR 1-4 years]) showed significantly lower MAPSE (8 mm [7-8.8] vs. 9.6 mm [8.1-11.5], p < 0.001). The association between decreased MAPSE (< 9 mm, optimal cut-off value by c-statistics) remained significant after adjustment for independent clinical and CMR predictors of MACE. The AUC of MAPSE for the prediction of MACE was 0.74 (CI 95% 0.65-0.82), significantly higher than that of LVEF (0.61 [CI 95% 0.50-0.71]; p < 0.001).

CONCLUSIONS

Reduced long-axis function assessed with MAPSE measurement using CINE CMR independently predicts long-term prognosis following STEMI. Moreover, MAPSE provided significantly higher prognostic implication in comparison with conventional LVEF measurement.

KEY POINTS

• MAPSE determined by CMR independently predicts long-term prognosis following STEMI. • MACE-free survival is significantly higher in patients with MAPSE ≥ 9 mm than < 9 mm. • MAPSE provides significantly higher prognostic implication than conventional LVEF.