Right ventricular function quantification in Takotsubo cardiomyopathy using two-dimensional strain echocardiography

Role of Imaging in Cardiomyopathies

Imaging has a central role in the diagnosis, classification, and clinical management of cardiomyopathies. While echocardiography is the first-line technique, given its wide availability and safety, advanced imaging, including cardiovascular magnetic resonance (CMR), nuclear medicine and CT, is increasingly needed to refine the diagnosis or guide therapeutic decision-making. In selected cases, such as in transthyretin-related cardiac amyloidosis or in arrhythmogenic cardiomyopathy, the demonstration of histological features of the disease can be avoided when typical findings are observed at bone-tracer scintigraphy or CMR, respectively. Findings from imaging techniques should always be integrated with data from the clinical, electrocardiographic, biomarker, genetic and functional evaluation to pursue an individualised approach to patients with cardiomyopathy.

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.

Imaging in Women with Heart Failure: Sex-specific Characteristics and Current Challenges

Cardiovascular disease (CVD) represents a significant threat to women's health. Heart failure (HF) is one CVD that still has an increasing incidence and about half of all cases involve women. HF is characterised by strong sex-specific features in aetiology, clinical manifestation and outcomes. Women are more likely to have hypertensive heart disease and HF with preserved ejection fraction, they experience worse quality of life but have a better overall survival rate. Women's hearts also have unique morphological characteristics that should be considered during cardiovascular assessment. It is important to understand and highlight these sex-specific features to be able to provide a tailored diagnostic approach and therapeutic management. The aim of this article is to review these aspects together with the challenges and the unique characteristics of different imaging modalities used for the diagnosis and follow-up of women with HF.

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.

Echocardiographic parameters associated with in-hospital adverse outcomes in patients with Takotsubo syndrome

INTRODUCTION

Takotsubo syndrome (TTS) is an acute heart failure syndrome that leads to significant morbidity and mortality. We sought to evaluate the association of cardiac mechanics on presentation with in-hospital adverse outcomes in patients with apical TTS.

METHODS

We retrospectively identified 468 patients with TTS based on ICD-9/10 codes between 2006 and 2017. The association of echocardiographic parameters with a composite outcome of heart failure and all-cause mortality during the index hospitalization was analyzed.

RESULTS

One hundred and forty one patients with the apical subtype and adequate imaging were included. 113 (80.1%) were female, left ventricular ejection fraction (LVEF) was 41.7% ± 12.4%, and global longitudinal strain was -10.1% ± 3.2%. The composite outcome occurred in 58 patients (41%), with heart failure occurring in 55 patients and death occurring in nine patients. Global longitudinal strain, global circumferential strain, global radial strain, right ventricular fractional area change, tricuspid annular plane systolic excursion, and right ventricular free wall strain were significantly worse in patients who experienced the composite outcome in univariate analyses. However, only LVEF was independently associated with the composite outcome in multivariable-adjusted analysis.

CONCLUSIONS

In patients with apical TTS, the strain has limited prognostic utility in the acute setting compared to LVEF, which was the only echocardiographic parameter associated with in-hospital heart failure and all-cause mortality.

Residual alterations of cardiac and endothelial function in patients who recovered from Takotsubo cardiomyopathy

Introduction

Takotsubo cardiomyopathy (TCM) is characterized by transient left ventricle dysfunction.

Hypothesis

A residual cardiac and endothelial dysfunction is present in patients who recovered from TCM.

Methods

In this single‐center prospective study, patients with prior TCM were included and followed for 6.4 ± 1.6 years. All underwent comprehensive cardiac function assessment, including tissue Doppler imaging (TDI) and 2‐dimensional strain (2DS) echocardiography at their first visit. The number of circulating endothelial progenitor cells and levels of proangiogenic vascular endothelial growth factor (VEGF) and its receptor (VEGF‐R) were measured. All measurements were compared with healthy controls.

Results

Forty‐two women (age 58. ±8.6 years, LVEF 58.1 ± 6.1%) comprised the TCM group. Patients post‐TCM had significantly lower early velocities E′ (6 (5.0–8.0) vs. 9 (7.0–11.0) cm/s, p = .001) by TDI and higher E/E′ ratio (p = .002), lower LV global average longitudinal strain (LGS) (−18.9 ± 3.5% vs. −21.7 ± 2.3%, p = .002) and RV LGS (−20.1 ± 3.9% vs. −23.4 ± 2.8%, p = .003) were evident. There was a trend toward a higher VEGF‐R (p = .09) along with decreased VEGF/VEGF‐R ratio representing inadequate VEGF production. In‐hospital mortality was not reported and only two non‐cardiac deaths occurred at long‐term follow‐up.

Conclusions

Altered TDI and 2DS indices suggest residual biventricular myocardial injury in post‐TCM patients with the apparent LV function recovery. Inappropriate production of VEGF and VEGF‐R were observed, suggesting a possible underlying endothelial dysfunction in these patients.

Takotsubo syndrome: the broken-heart syndrome

Takotsubo syndrome - also known as broken-heart syndrome, Takotsubo cardiomyopathy, and stress-induced cardiomyopathy - is a recently discovered acute cardiac disease first described in Japan in 1991. This review aims to update understanding on the epidemiology, pathophysiology, clinical presentation, diagnosis, and treatment of Takotsubo syndrome, highlighting aspects of interest to cardiologists and general practitioners.

Left ventricular global longitudinal strain assessment in patients with takotsubo cardiomyopathy: a call for an echocardiography-based classification

BACKGROUND

Takotsubo cardiomyopathy (TTC) is classified into 4 types depending on the anatomical area affected identified on gross visual assessment. We have sought to understand if it is feasible and advantageous to use left ventricular global longitudinal strain (LVGLS), LV segmental longitudinal strain and right ventricle free wall strain (RVFWS) to classify TTC.

METHODS

We conducted a retrospective observational study on twenty-five patients who meet the Modified Mayo Clinic Criteria for TTC [1]. Two independent reviewers performed strain analysis, they were both blinded to patient's diagnosed classification and outcomes.

RESULTS

Based on classification by traditional assessment the 92% (N.=23) were diagnosed with typical TTC, indicating apical involvement. The entire LV was affected, 67% (N.=16) had abnormal strain (STE>-18) in all three LV regions (base, mid-ventricle and apex). Seventy-one percent of patients (N.=17) had abnormal LVGLS (>-18). Abnormal strain across all three LV regions was associated with higher prevalence (70%, N.=8 Vs 30%, N.=4, respectively) of composite cardiovascular events and longer length of hospital stay. There was a statistically significant difference in average length of hospital stay in those patients who had abnormal strain in all three regions compared to those that did not have abnormal strain across all three regions (8 days compared to 3.44 days, P=0.02).

CONCLUSIONS

A new classification of TCC based on strain analysis should be developed. The traditional model is arbitrary; it fails to recognize that in most patients the entire LV is affect, it does not have prognostic significance and the most prevalent typical variant indicates apical involvement. Our study suggests that the entire LV is affected, and strain analysis has prognostic significance.

Right and Left Ventricular Takotsubo: Same Two-Headed Monster or Different Beasts?

Right ventricular involvement in takotsubo cardiomyopathy is poorly understood and may be more common than previously reported. The significant hemodynamic ramification of this condition is elicited in this case report in which an 81-year-old female suffered a deadly biventricular takotsubo cardiomyopathy with subsequent resolution of left ventricular function but the persistence of right ventricular dysfunction. In this case, we highlight the importance of shifting focus to different recovery patterns within the two ventricles. Through a review of published cases, we have found an absence of attention to the right ventricle, an inconsistency in the appropriate diagnostic criteria of right ventricular takotsubo, and a lack of reporting on its recovery timing. This knowledge gap requires future studies.

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.

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.

Right ventricular strain assessment by cardiovascular magnetic resonance myocardial feature tracking allows optimized risk stratification in Takotsubo syndrome

Background

A substantial number of patients with Takotsubo syndrome (TTS) exhibit right ventricular (RV) dysfunction which has been associated with adverse outcome. The aim of this study was to assess the clinical and prognostic value of RV myocardial strain in TTS using cardiovascular magnetic resonance myocardial feature tracking (CMR-FT).

Methods

CMR-FT was performed in a core laboratory to determine RV longitudinal strain in 134 TTS patients undergoing CMR in median 2 days after admission to 2 experienced centers. For comparison, RV involvement was evaluated by sole visual assessment concerning RV contraction abnormalities. Both approaches were analyzed regarding their long-term prognostic value.

Results

The peak global RV longitudinal strain was in median -19%. Segmental analyses located contraction abnormalities primarily in the apical parts of the right ventricle. Sole visual assessment identified 38 patients (28%) with RV involvement. These patients showed a numerically higher long-term mortality without reaching statistical significance (17.1% versus 10.5%; hazard ratio 1.38 [95% confidence interval 0.49–3.88]; p = 0.31). The optimal RV strain cutoff value for risk prediction was -17.24%. Stratification according to this threshold categorized 41% of TTS patients (n = 55) in the high-risk group which demonstrated a significantly increased long-term mortality compared to patients with preserved global RV strain (20.0% versus 7.0%; hazard ratio 2.98 [95% confidence interval 1.02–8.73]; p = 0.03).

Conclusions

The assessment of RV myocardial strain using CMR-FT enables an accurate evaluation of RV involvement in TTS and represents a promising approach for optimized risk stratification.

Speckle tracking analysis in intensive care unit: A toy or a tool?

The use of conventional echocardiography in the intensive care unit (ICU) is today established to assess left and right ventricular systolic function, for preload determination and procedural guidance. Next step in ICU echocardiography could be the use of novel ultrasound techniques such as strain echocardiography to assist in the management of patients with acute coronary syndrome, heart failure, or pulmonary embolism. This review has gathered the available evidence supporting the incremental value of strain in the diagnostic workup of cardiac diseases treated in ICU.

Role of echocardiography for takotsubo cardiomyopathy: clinical and prognostic implications

Takotsubo cardiomyopathy (TTC) is newly-described secondary cardiomyopathy characterized by transient left ventricular (LV) dysfunction, which is increasingly recognized in the field of cardiology. TTC occurs in approximately 2% of the patients with acute coronary syndrome. Its onset is rare; however, its specific features play a crucial role in diagnosing the chest pain in clinical practice. TTC has generally favorable outcome with rapid recovery of LV function; however, an increasing evidence suggests that it should be regarded as a more serious acute cardiac disorder with a variety of complications. Owing to its widespread availability, even in emergency settings, transthoracic echocardiography plays a key role in the diagnostic assessment of TTC and contributes to an increased number of disease detection and incidence reports in contemporary clinical practice. This review focuses on the role of echocardiography in understanding the clinical prognostic implications in patients with TTC.

Importance of temporal changes in myocardial strain in Takotsubo cardiomyopathy

Strain imaging is a sensitive marker of myocardial dysfunction and may be underused in Takotsubo cardiomyopathy (TC). We present a case of biventricular TC in which early improvement in left ventricular longitudinal strain predated subsequent improvement in ejection fraction. Early temporal patterns of strain of the left and right ventricles have not previously been described in TC. Our case illustrates how strain can be a sensitive marker for myocardial dysfunction and recovery in TC. Increased use of strain in TC may have further implications on prognosis and management.

Right Ventricular Involvement and Recovery After Acute Stress-Induced (Tako-tsubo) Cardiomyopathy

Acute stress-induced (Tako-tsubo) cardiomyopathy is an increasingly recognized but insufficiently characterized syndrome. Here, we investigate the pathophysiology of right ventricular (RV) involvement in Tako-tsubo and its recovery time course. We prospectively recruited 31 patients with Tako-tsubo with predominantly ST-elevation electrocardiogram and 18 controls of similar gender, age, and co-morbidity distribution. Patients underwent echocardiography and cardiac magnetic resonance (CMR) imaging on a 3T Philips scanner in the acute phase (day 0 to 3 after presentation) and at 4-months follow-up. Visually, echocardiography was able to identify only 52% of patients who showed RV wall motion abnormalities on CMR. Only CMR-derived RV ejection fraction (p = 0.01) and echocardiography-estimated pulmonary artery pressure (p = 0.01) identify RV functional involvement in the acute phase. Although RV ejection fraction normalizes in most patients by 4 months, acutely there is RV myocardial edema in both functioning and malfunctioning segments, as measured by prolonged native T1 mapping (p = 0.02 for both vs controls), and this persists at 4 months in the acutely malfunctioning segments (p = 0.002 vs controls). The extracellular volume fraction was significantly increased acutely in all RV segments and remained increased at follow-up compared with controls (p = 0.004 for all). In conclusion, in a Tako-tsubo population presenting predominantly with ST-elevation electrocardiogram, we demonstrate that although RV functional involvement is seen in only half of the patients, RV myocardial edema is present acutely throughout the RV myocardium in all patients and results in microscopic fibrosis at 4-month follow-up.

Rare Variants in Cardiomyopathy Genes Associated With Stress-Induced Cardiomyopathy

BACKGROUND

Stress-induced cardiomyopathy (SIC) is a poorly understood condition associated with periods of emotional and physical stress. The clinical approaches for management of SIC are supportive and reactive to patient symptoms.

OBJECTIVE

To utilize next-generation exome sequencing to define genetic variation associated with, and potentially responsible for, this disease.

METHODS

We performed exome sequencing of 7 white female patients with SIC. Filtering of the identified variants was performed to limit our investigation to those sequences that passed quality control criteria, were rare or novel, were determined algorithmically to have high impact on the associated protein, and were within regions of high species conservation. All variants were verified by using Sanger sequencing.

RESULTS

Exome-sequencing analysis revealed that each patient carried predicted deleterious variants affecting known cardiomyopathy genes. In each case, the identified variant was either not previously found in public human genome data or was previously annotated in a database of clinical variants associated with cardiac dysfunction.

CONCLUSION

Patients with SIC harbor deleterious mutations in established cardiomyopathy genes at a level higher than healthy controls. We hypothesize that patients at highest risk for SIC likely live in a compensated state of cardiac dysfunction that manifests clinically only after the myocardium is stressed. In short, we propose that SIC is another example of an occult cardiomyopathy with a distinct physiological trigger and suggest that alternative clinical approaches to these patients may be warranted.

ABBREVIATIONS

CADD, Combined Annotation Dependent DepletionFPKM, fragments per kilobase pair of exon per million fragments mappedNHLBI GO ESP, National Heart, Lung, and Blood Institute Grand Opportunity Exome Sequencing ProjectPCR, polymerase chain reactionSIC, stress-induced cardiomyopathy.