Geometry as a Confounder When Assessing Ventricular Systolic Function

Usefulness of speckle-tracking echocardiography for early detection in children with Duchenne muscular dystrophy: a meta-analysis and trial sequential analysis

Background

Duchenne muscular dystrophy (DMD) is the most common form of inherited muscle disease in children. The incidence of cardiomyopathy induced by DMD increases with age. Left ventricular ejection fraction usually fails to reflect the subclinical left ventricular dysfunction. Several studies have assessed this dysfunction using myocardial strain measured by speckle-tracking echocardiography (STE). However, the results were inconsistent and incomplete.

Methods

Several databases were searched from their inception to February 5, 2020. The summarized weighted mean difference (WMD) with 95% confidence intervals (CIs) were estimated for myocardial strain between DMD and healthy controls and a meta-analysis was conducted. Trial sequential analysis estimated whether the resulting evidence was sufficient.

Results

Eight studies with a total of 269 DMD children and 299 healthy participants were included. STE revealed that global longitudinal strain (GLS), global circumferential strain, average longitudinal strain (measured by two-dimensional STE at the apical four-chamber view), and average circumferential strain (measured by two-dimensional STE at the papillary muscle short-axis level) decreased (WMD = 4.17, 95% CI: 3.03–5.32; WMD = 3.98, 95% CI: 0.29–7.68; WMD = 4.18, 95% CI: 2.75–5.62; and WMD = 4.90, 95% CI: 2.38–7.43, respectively; all P < 0.05) compared with the controls and global radial strain was unchanged in the DMD group (WMD = − 4.33, 95% CI: − 9.53–0.87, P = 0.103). Trial sequential analysis indicated that available GLS samples were sufficient and confirmed that adequate evidence was accumulated. The credibility of other myocardial strains was questioned due to insufficiently involved studies.

Conclusion

GLS can be useful for early detection of left ventricle myocardial dysfunction in children with DMD.

Impaired global longitudinal strain in elderly patients with preserved ejection fraction is associated with raised post-exercise left ventricular filling pressure

BACKGROUND

The purpose of this study was to evaluate whether impaired resting global longitudinal strain (GLS) in elderly patients with preserved left ventricular (LV) ejection fraction (EF) is associated with raised post-exercise LV filling pressure estimated by the ratio of early diastolic transmitral flow velocity to annulus velocity (E/e').

METHODS

Seventy elderly patients (age = 74 ± 6 years, male 40 patients) who underwent treadmill stress echocardiography were studied. All patients had normal sinus rhythm, normal LV wall motion at rest, and had preserved LVEF ≥ 50%. Patients with exercise induced wall motion abnormality were not included. GLS at rest was measured using automated functional imaging.

RESULTS

Twenty-four of the 70 patients had raised post-exercise LV filling pressure indicated by septal E/e' ≥ 15.0. Patients with raised post-exercise LV filling pressure had smaller resting GLS than that in patients without it (- 16.9 ± 1.8 vs. - 19.6 ± 2.5%, respectively, p < 0.0001). Downward stepwise multivariate logistic regression analysis demonstrated that resting GLS was one of independent predictors of raised post-exercise E/e'. Receiver operating characteristic (ROC) curve analysis had demonstrated that optimal cutoff point for resting GLS to predict raised post-exercise E/e' was - 17.8% (sensitivity 83.3%, specificity 80.4%, respectively), and the area under the ROC curve was 0.820.

CONCLUSION

In elderly patients with preserved LVEF and without obvious myocardial ischemia, impaired resting GLS at rest is associated with raised post-exercise LV filling pressure estimated by E/e' ≥ 15.0.

Importance of Nonlongitudinal Motion Components in Right Ventricular Function: Three-Dimensional Echocardiographic Study in Healthy Volunteers

BACKGROUND

Global right ventricular (RV) function is determined by the interplay of different motion components related to the myofiber architecture, and the relative importance of these components is still not thoroughly characterized. The aims of this study were to quantify the relative contributions of longitudinal, radial, and anteroposterior motion components to global RV function and to examine their determining factors in a large cohort of healthy volunteers using three-dimensional echocardiography.

METHODS

Three hundred healthy adults with a balanced age range and an equal sex distribution were investigated at two centers. A three-dimensional mesh model of the right ventricle was generated, and its motion was decomposed along the three anatomically relevant axes. Multiplicative relative contributions were measured by dividing the ejection fraction (EF) values generated by shortening in the longitudinal, radial, and anteroposterior directions by global RV EF (longitudinal EF index [LEFi], radial EF index [REFi], and anteroposterior EF index, respectively). The circumferential contribution was defined as shortening in the radial and anteroposterior directions, omitting only longitudinal shortening.

RESULTS

Circumferential EF index was markedly higher compared with LEFi (79 ± 7% vs 47 ± 9%, P < .001). LEFi (47 ± 9%) and anteroposterior EF index (49 ± 7%) were found to be similar in the pooled population, whereas REFi (44 ± 10%) was lower (P < .001). In younger individuals (20-39 years of age), the relative contribution of longitudinal shortening was significantly higher compared with the radial component; however, in the older age groups, LEFi and REFi were comparable. Age, body surface area, heart rate, and RV end-diastolic volume were independent predictors of LEFi and REFi, but all with opposite effects on the two motion directions.

CONCLUSIONS

In contrast to the traditional viewpoint, the contributions of the radial and anteroposterior motion directions may be of comparable significance with that of longitudinal shortening in determining global RV function. Standard parameters referring only to longitudinal shortening of the right ventricle may be inadequate to characterize RV function thoroughly.

2- and 3-Dimensional Myocardial Strain in Cardiac Health and Disease

Advances in speckle-tracking echocardiography allowed the rise of deformation imaging as a feasible, robust, and valuable tool for clinical routine. The global or segmental measurement of strain can objectively quantify myocardial deformation and can characterize myocardial function in a novel way. However, the proper interpretation of deformation measurements requires understanding of cardiac mechanics and the influence of loading conditions, ventricular geometry, conduction delays, and myocardial tissue characteristics on the measured values. The purpose of this manuscript is to review the basic concepts of deformation imaging, briefly describe imaging modalities for strain assessment, and discuss in depth the underlying physical and pathophysiological mechanisms which lead to the respective findings in a specific disease.

Incremental Value of Global Longitudinal Strain for Predicting Survival in Patients With Advanced AL Amyloidosis

BACKGROUND

Advanced light-chain (AL) amyloidosis is associated with poor prognosis, with a 5-year survival rate of <25%. Prognostication is based on the revised Mayo (rMayo) staging according to serum cardiac biomarkers.

OBJECTIVES

This study sought to determine whether global longitudinal strain (GLS) can provide incremental prognostic value in patients with advanced disease.

METHODS

Baseline (pre-treatment) clinical, 2-dimensional echocardiogram with GLS and laboratory data were collected prospectively in 94 patients with newly diagnosed AL amyloidosis with rMayo stage III or IV disease. Overall survival (OS) was defined as time from baseline echocardiography to death.

RESULTS

Of 94 patients, 60% (n = 56) had rMayo stage III and 40% (n = 38) had stage IV disease. Ninety of the 94 patients underwent plasma cell-directed therapy. The median left ventricular ejection fraction (LVEF) was 60%, and the median GLS was 13.2%. Of 94 patients, 64 died during follow-up. The median OS was 11.2 months, with an estimated 5-year OS of 21%. In univariable analysis, brain natriuretic peptides, GLS, LVEF, E/e' ratio, and rMayo stage were significantly associated with OS. In Cox regression, GLS provided incremental value over brain natriuretic peptide, troponin, and LVEF for predicting OS. Patients with GLS < -14.2% had a corresponding median OS and 5-year OS rate of 33.2 months and 39%, respectively, versus 7.7 months and 6% for those with GLS ≥ -14.2%. This difference was maintained despite further stratification by rMayo stage.

CONCLUSIONS

Baseline GLS is an independent predictor of OS beyond the circulating biomarkers and can identify groups with different survival outcomes beyond the Mayo Staging.

Sensitive marker for evaluation of hypertensive heart disease: extracellular volume and myocardial strain

Background

Evaluation of tissue fibrosis and myocardial hypertrophy in left ventricular (LV) remodeling is the basis of post-treatment evaluation of hypertensive heart disease (HHD). Extracellular volume (ECV) and myocardial strain parameters can indirectly reflect the changes of both. Our objective was to analyze the characteristics of ECV and strain parameters in LV myocardium of HHD with varying degrees of systolic dysfunction, and to explore the changes of both after treatment for hypertension.

Methods

A total of 62 HHD patients were divided into 3 groups according to ejection fraction (EF < 30, 30%≦EF < 50%, EF≧50%). Twenty-one of these patients underwent cardiac magnetic resonance (CMR) reexamination more than six months after receiving antihypertensive medication. The initial T1 time and post-enhancement T1 time of each segment were measured, and the ECV was calculated. Radial strain (RS), circumferential strain (CS) and longitudinal strain (LS) of LV were measured by cvi42 software, and the differences in CMR parameters between different groups and before and after treatment were compared.

Results

①The mean, basal and middle ECV value of HHD groups with different EF were all higher than that of the control group (P < 0.05), but the difference between HHD groups was not statistically significant. ②With the decrease of EF, the absolute value of both the global or local strain decreased. Strain is related to LVMI and ECV. ③In general, ECV, global RS (GRS) and global CS (GCS) improved after treatment, but the improvement of LS impairment in HHD patients is difficult.

Conclusions

ECV and myocardial strain parameters are more sensitive to myocardial abnormalities, and ECV, GRS and GCS are more sensitive to treatment. However it is difficult to improve longitudinal strain impairment in HHD patients. ECV and myocardial strain parameters can be used as good makers for long-term monitoring of the efficacy of HHD patients.

Impact of the left anterior descending artery wrapping around the left ventricular apex on cardiac mechanics in patients with normal coronary angiography

Background

We examined the impact of left anterior descending (LAD) wrapping on left ventricular (LV) mechanics in patients with normal coronary angiography. Seventy-one patients with evidence of normal coronary angiography (LAD wrapping: n = 52, 73%) and LAD non-wrapping (n = 19, 27%) were included in the study. Using 2D-strain imaging, we measured LV longitudinal and circumferential (circ) strain (ε_sys), systolic strain rate (SR_sys), early (SR_e) and atrial (SR_a) diastolic SR, LV electromechanical dyssynchrony (TTP-SD), and LV twist and torsion in study groups.

Results

No significant difference in age, gender, body surface area (BSA), or ejection fraction (EF%) between groups. LAD-wrapping group showed higher deceleration time (DT) (P < 0.0001), global longitudinal ε_sys % (P < 0.02), circ SR_a at the basal segments (P < .02), circ SR_sys and SR_e, and SR_a (P < 0.0001) at the apical segments and apical rotation compared with the non-wrapped group. LV twist was correlated negatively with LV electromechanical dyssynchrony (r = .25, P < 0.03) and positively with longitudinal ε_sys (r = .47, P < .0001), circ ε_sys% (r = .55, P < .0001), circ SR_sys (r = .23, P < .05), and circ SR_e (r = .55, P < .0001). Using multivariate regression analysis, DT: OR 0.932, CI 0.877–0.991, and P < 0.02 and circ at atrial diastole (SR_a): OR 0.000, CI .000–.271, and P < 0.03 were independent predictors of LAD wrapping around LV apex.

Conclusion

Wrapped LAD is associated with better myocardial relaxation and rotational mechanics in patients with normal coronary angiography. This could explain the worse prognosis in such population when LAD occlusion acutely emerges.

Speckle tracking echocardiography in hypokinetic non-dilated cardiomyopathy: comparison with dilated cardiomyopathy

Aims

Hypokinetic non‐dilated cardiomyopathy (HNDC), which is determined by impaired left ventricular (LV) systolic function despite normal LV size, has been categorized as a subgroup of dilated cardiomyopathy (DCM) spectrum. Lack of data regarding advanced echocardiographic data in this population motivated us to design the present study in order to assess LV myocardial deformation properties of HNDC patients against the ones with dilated left ventricle.

Methods and results

Thirty‐one HNDC patients and 23 DCM patients were enrolled in the study consecutively. Myocardial deformation parameters including global longitudinal strain, global circumferential strain, LV basal and apical rotation, LV twist, and LV mechanical dispersion were obtained with the use of two‐dimensional speckle tracking‐based methods in all patients. Left cardiac chamber volume was also measured using three‐dimensional HeartModel application. Patients with enlarged left ventricle tend to have lower LV ejection fraction. Comparing with HNDC group, DCM patients showed worse global circumferential strain (coefficient ± standard error 3.59 ± 0.94, P < 0.001) and LV mechanical dispersion (coefficient ± standard error 16.46 ± 7.09, P = 0.02) after regression analysis, while neither the global longitudinal strain nor the LV twist was not significantly different between two study population.

Conclusions

Left ventricular enlargement has a substantial effect on the circumferential strain and mechanical dispersion more than other deformation parameters that may play a role in the assumed poor prognosis of heart failure patients with dilated left ventricle.

New expectations for diastolic function assessment in transthoracic echocardiography based on a semi-automated computing of strain–volume loops

Aims

Early diagnosis of heart failure with preserved ejection fraction (HFpEF) by determination of diastolic dysfunction is challenging. Strain–volume loop (SVL) is a new tool to analyse left ventricular function. We propose a new semi-automated method to calculate SVL area and explore the added value of this index for diastolic function assessment.

Method and results

Fifty patients (25 amyloidosis, 25 HFpEF) were included in the study and compared with 25 healthy control subjects. Left ventricular ejection fraction was preserved and similar between groups. Classical indices of diastolic function were pathological in HFpEF and amyloidosis groups with greater left atrial volume index, greater mitral average E/e’ ratio, faster tricuspid regurgitation (P &lt; 0.0001 compared with controls). SVL analysis demonstrated a significant difference of the global area between groups, with the smaller area in amyloidosis group, the greater in controls and a mid-range value in HFpEF group (37 vs. 120 vs. 72 mL.%, respectively, P &lt; 0.0001). Applying a linear discriminant analysis (LDA) classifier, results show a mean area under the curve of 0.91 for the comparison between HFpEF and amyloidosis groups.

Conclusion

SVLs area is efficient to identify patients with a diastolic dysfunction. This new semi-automated tool is very promising for future development of automated diagnosis with machine-learning algorithms.

Sex differences in anthracycline-induced cardiotoxicity: the benefits of estrogens

Anthracyclines are the cornerstone for many oncologic treatments, but their cardiotoxicity has been recognized for several decades. Female subjects, especially before puberty and adolescence, or after menopause, seem to be more at increased risk, with the prognostic impact of this sex issue being less consistent compared to other cardiovascular risk factors. Several studies imply that sex differences could depend on the lack of the protective effect of sex hormones against the anthracycline-initiated damage in cardiac cells, or on differential mitochondria-related oxidative gene expression. This is also reflected by the results obtained with different diagnostic methods, such as cardiovascular biomarkers and imaging techniques (echocardiography, magnetic resonance, and nuclear medicine) in the diagnosis and monitoring of cardiotoxicity, confirming that sex differences exist. The same is true about protective strategies from anthracycline cardiotoxicity. Indeed, first studied to withstand oxidative damage in response to ischemia/reperfusion (I/R) injury, cardioprotection has different outcomes in men and women. A number of studies assessed the differences in I/R response between male and female hearts, with oxidative stress and apoptosis being shared mechanisms between the I/R and anthracyclines heart damage. Sex hormones can modulate these mechanisms, thus confirming their importance in the pathophysiology in cardioprotection not only from the ischemia/reperfusion damage, but also from anthracyclines, fueling further cardio-oncologic research on the topic.

Application of strain echocardiography in valvular heart diseases

Echocardiographic strain imaging allows new insight into a complex cardiac mechanics and enables more precise evaluation of cardiac function. Hence, it has been shown to have clinical utility in a variety of valvular heart diseases. In particular, global longitudinal strain has been shown to be more sensitive to detect systolic dysfunction than left ventricular ejection fraction. In patients with valvular heart diseases, it provides both diagnostic and prognostic information in addition to standard echocardiographic and clinical parameters. In this review, we summarize current clinical application of strain echocardiography in patients with valvular heart diseases and discuss pathophysiological mechanisms that lead to respective findings in specific diseases.

Subclinical progression of systemic sclerosis-related cardiomyopathy

AIMS

Cardiac involvement in patients with systemic sclerosis (SSc) is frequent and represents a negative prognostic factor. Recent studies have described subclinical heart involvement of both the right ventricle (RV) and left ventricle (LV) via speckle-tracking-derived global longitudinal strain (GLS). It is currently unknown if SSc-related cardiomyopathy progresses through time. Our aim was to assess the progression of subclinical cardiac involvement in patients with SSc via speckle-tracking-derived GLS.

METHODS

This was a prospective longitudinal study enrolling 72 consecutive patients with a diagnosis of SSc and no structural heart disease nor pulmonary hypertension. A standard echocardiographic exam and GLS calculations were performed at baseline and at follow-up.

RESULTS

Traditional echocardiographic parameters did not differ from baseline to 20-month follow-up. LV GLS, despite being already impaired at baseline, worsened significantly during follow-up (from -19.8 ± 3.5% to -18.7 ± 3.5%, p = .034). RV GLS impairment progressed through the follow-up period (from -20.9 ± 6.1% to -18.7 ± 5.4%, p = .013). The impairment was more pronounced for the endocardial layers of both LV (from -22.5 ± 3.9% to -21.4 ± 3.9%, p = .041) and RV (-24.2 ± 6.2% to -20.6 ± 5.9%, p = .001). A 1% worsening in RV GLS was associated with an 18% increased risk of all-cause death or major cardiovascular event (p = .03) and with a 55% increased risk of pulmonary hypertension (p = .043).

CONCLUSION

SSC-related cardiomyopathy progresses over time and can be detected by speckle-tracking GLS. The highest progression towards reduced deformation was registered for the endocardial layers, which supports the hypothesis that microvascular dysfunction is the main determinant of heart involvement in SSc patients and starts well before overt pulmonary hypertension.

Relationship between Microfibrillar-Associated Protein 4 Levels and Subclinical Myocardial Damage in Chronic Kidney Disease

INTRODUCTION

Chronic kidney disease (CKD) is a widespread health problem, in which mortality is most frequently due to cardiovascular diseases. Microfibrillar-associated protein 4 (MFAP4) is an extracellular matrix protein. MFAP4 is involved in several biological processes, particularly the maintenance of vascular integrity and extracellular matrix remodeling. Our review of the literature revealed no data concerning MFAP4 levels in CKD and its relationship with myocardial functions.

OBJECTIVE

The purpose of this study was therefore to investigate MFAP4 levels in CKD, parameters affecting these, and the relationship with myocardial functions.

MATERIALS AND METHODS

Seventy-nine CKD patients and 30 healthy controls were included in the study. Routine biochemical tests and echocardiography were performed once demographic data had been recorded. Blood specimens were collected for MFAP4 analysis, and the results were subjected to statistical analysis.

RESULTS

MFAP4 levels were significantly higher in the patient group than in the control group (p< 0.001). Doppler parameters revealed more frequent LV diastolic impairment in the patient group. Tissue Doppler systolic velocity and global longitudinal strain were significantly impaired, revealing the subclinical LV systolic dysfunction in CKD patients. MFAP4 elevation in the patient group was positively correlated with aortic root (AR), global circumferential strain (GCS), and GCS rate.

CONCLUSION

Our results showed MFAP4 elevation in CKD for the first time in the literature, and that this elevation may be related to GCS and AR dilation. We think that, once supported by further studies, MFAP4 may constitute a marker in the evaluation of myocardial functions in CKD.

The Utility of Cardiac Reserve for the Early Detection of Cancer Treatment-Related Cardiac Dysfunction: A Comprehensive Overview

With progressive advancements in cancer detection and treatment, cancer-specific survival has improved dramatically over the past decades. Consequently, long-term health outcomes are increasingly defined by comorbidities such as cardiovascular disease. Importantly, a number of well-established and emerging cancer treatments have been associated with varying degrees of cardiovascular injury that may not emerge until years following the completion of cancer treatment. Of particular concern is the development of cancer treatment related cardiac dysfunction (CTRCD) which is associated with an increased risk of heart failure and high risk of morbidity and mortality. Early detection of CTRCD appears critical for preventing long-term cardiovascular morbidity in cancer survivors. However, current clinical standards for the identification of CTRCD rely on assessments of cardiac function in the resting state. This provides incomplete information about the heart's reserve capacity and may reduce the sensitivity for detecting sub-clinical myocardial injury. Advances in non-invasive imaging techniques have enabled cardiac function to be quantified during exercise thereby providing a novel means of identifying early cardiac dysfunction that has proved useful in several cardiovascular pathologies. The purpose of this narrative review is (1) to discuss the different non-invasive imaging techniques that can be used for quantifying different aspects of cardiac reserve; (2) discuss the findings from studies of cancer patients that have measured cardiac reserve as a marker of CTRCD; and (3) highlight the future directions important knowledge gaps that need to be addressed for cardiac reserve to be effectively integrated into routine monitoring for cancer patients exposed to cardiotoxic therapies.

Abnormal aortic flow conduction is associated with increased viscous energy loss in patients with repaired tetralogy of Fallot

OBJECTIVES

Aortopathy in tetralogy of Fallot (TOF) is characterized by increased aortic stiffness, dilation and reduced left ventricular (LV) function. Repair in infancy normalizes aortic dimensions in early childhood. Our prior work demonstrated that early TOF repair does not normalize aortic compliance and that abnormal ascending aortic flow patterns are prevalent. The objectives of this study were to: (i) determine whether proximal aortic flow-mediated viscous energy loss (EL') is elevated in patients with early TOF repair compared with healthy controls, and (ii) determine whether the degree of EL' is associated with LV function.

METHODS

Forty-one patients post TOF repair with normalized aortic size and 15 healthy controls underwent 4-dimenisonal-flow magnetic resonance imaging flow analysis and EL' assessment. Correlations between EL', aortic size, and LV function were assessed.

RESULTS

The TOF group had increased peak systolic thoracic aorta EL' (3.8 vs 1.5 mW, P = 0.004) and increased averaged EL' throughout the cardiac cycle (1.2 vs 0.5 mW, P = 0.003). Peak and mean systolic EL' in the ascending aorta was increased 2-fold in the TOF group compared with control (peak: 2.0 vs 0.9 mW, P = 0.007). Peak EL' measured along the entire thoracic aortic length correlated with LV ejection fraction (R = -0.45, P = 0.009), indexed LV end-systolic volume (R = -0.40, P = 0.010), and right ventricular end-systolic volume (R = -0.37, P = 0.034).

CONCLUSIONS

Patients with repaired TOF exhibit abnormal aortic flow associated with increased EL' in the thoracic aorta. The magnitude of EL' is associated with LV function and volumes. Increased aortic EL' in TOF is likely due to inherently abnormal LV outflow geometry and or right ventricular interaction. Reduced aortic flow efficiency in TOF increases cardiac work and may be an important factor in long-term cardiac performance.

Myocardial longitudinal strain, fitness, and heart failure risk factors in young adults

AIMS

To investigate the relationship between fitness, heart failure (HF) risk factors (age, blood pressure, and obesity), and global/regional myocardial longitudinal strain in young adults undergoing stress testing.

METHODS

Individuals 25-55 years old without any significant medical history, not taking medications, and with a normal maximal stress echocardiogram were eligible. Global and regional longitudinal strain (LS) was evaluated by 2D speckle tracking echocardiography.

RESULTS

One hundred and seventy patients were included, of which 60% were males. The mean age was 43 years old, 49% had optimal blood pressure, and 30% were obese. On average, patients achieved 10.5 (3) METS, and the global LS was -19.9 (3.1) %. Reduced fitness was associated with decreased global longitudinal strain (GLS). Those in the top GLS quartile walked on average 1 minute and 21 seconds longer compared with the lowest quartile (P < .001). The effect of fitness on LS was preferential to the mid and apex, such that there was an apex-to-base gradient. Obesity was also independently associated with reduced GLS. However, the reduction in LS in obese individuals was more prominent at the base and mid-walls with relative sparing of the apex. Similar to fitness, aging was also associated with an increase in the apex-to-base gradient of LS. Furthermore, diastolic filling parameters correlated distinctively with regional LS.

CONCLUSIONS

In young adults without cardiovascular disease, low fitness and obesity are independently associated with reduced left ventricular longitudinal strain. There is a differential effect of HF risk factors on regional longitudinal function.

Impact of sex and myocardial function on association of obesity with mortality in Asian patients with acute heart failure: a retrospective analysis from the STRATS-AHF registry

OBJECTIVES

Impact of sex and myocardial function on the obesity paradox in heart failure (HF) is unknown. We explored whether sex, myocardial function, and left ventricular (LV) geometry explains the protective association of body mass index (BMI) with mortality, and investigated whether metabolic health status affects this association.

DESIGN

A multicentre cohort study with patients with acute HF admitted from January 2009 to December 2016 with a median follow-up of 33.7 months.

SETTING

Three tertiary hospitals.

PARTICIPANTS

A total of 2021 overweight-to-obese (OW) and 1543 normal-weight (NW) patients with acute HF.

MEASUREMENTS

The primary outcome was all-cause mortality. Patients were categorised as either OW (BMI≥23kg/m²) or NW (BMI<23kg/m²). BMI was used as both categorical and continuous variables. Clinical, laboratory and echocardiographic measures, including LV global longitudinal strain (LV-GLS), LV-ejection fraction, LV geometry, were obtained.

RESULTS

During the follow-up period, 1392 patients died (685 OW and 707 NW). BMI was significantly associated with mortality in univariate (HR=0.929 per kg/m², p<0.001) and multivariate analyses (HR=0.954 per kg/m², p<0.001). In multivariable fractional polynomials, higher BMIs were associated with lower mortality overall and in subgroups by sex, LV-GLS and LV geometry, with a steeper association in men (p-interaction <0.001). In women, there were significant interactions of BMI with LV-GLS (p-interaction=0.044) and age (p-interaction=0.040) for mortality; the protective association of BMI with mortality was confined to subgroups with high LV-GLS (>10.1%) or elderly patients (≥75 years). In men, this association was found in all subgroups without significant interaction. Metabolically healthy obese patients had better survival than metabolically unhealthy obese patients (log-rank p<0.001).

CONCLUSIONS

In women, a significant interaction was observed between BMI and age or LV-GLS in association with mortality, suggesting that sex, ageing and myocardial dysfunction can affect the magnitude of the obesity paradox in HF. Metabolic health status provides prognostic information beyond obesity status.

TRIAL REGISTRATION NUMBER

Registry: ClinicalTrials.gov Number: NCT03513653 (https://clinicaltrials.gov/ct2/show/NCT03513653).

Myocardial Strain in the Assessment of Patients With Heart Failure: A Review

Importance

The cornerstones of imaging in heart failure (HF) are the measurement of systolic and diastolic function and left ventricular (LV) filling pressure.

Observations

Ejection fraction and the assessment of LV filling pressure and diastolic dysfunction using the ratio of early transmitral flow and LV relaxation (E/e') are conventional imaging markers of LV function. Despite their extensive use in HF guidelines, both have significant detractions, especially in an era when HF with preserved ejection fraction is becoming the dominant presentation. In contrast, strain imaging has provided a new window into myocardial mechanics. Myocardial strain is now well validated, robust, and can easily be performed on most modern echocardiography machines. This Review summarizes the evidence in 9 situations across the stages of HF where LV global longitudinal strain and other strain parameters may provide information on risk prediction, diagnosis, assessment of treatment response, and follow-up.

Conclusions and Relevance

The evolution of myocardial deformation imaging from research tool to clinical practice will provide clinicians with a useful additional imaging parameter to facilitate the assessment and risk evaluation of patients with HF.

Regional right ventricular function in rats: a novel magnetic resonance imaging method for measurement of right ventricular strain

The function of the right ventricle (RV) is linked to clinical outcome in many cardiovascular diseases, but its role in experimental heart failure remains largely unexplored due to difficulties in measuring RV function in vivo. We aimed to advance RV imaging by establishing phase-contrast MRI (PC-MRI) as a robust method for measuring RV function in rodents. A total of 46 Wistar-Hannover rats with left ventricular (LV) myocardial infarction and 10 control rats (sham) were examined 6 wk after surgery. Using a 9.4-T preclinical MRI system, we utilized PC-MRI to measure strain/strain rate in the RV free wall under isoflurane anesthesia. Cine MRI was used to measure RV volumes. LV end-diastolic pressure (LVEDP) was measured and used to identify pulmonary congestion. The infarct rats were divided into two groups: those with signs of pulmonary congestion (PC), with LVEDP ≥ 15 mmHg ( n = 26) and those without signs of pulmonary congestion (NPC), with LVEDP < 15 mmHg ( n = 20). The NPC rats exhibited preserved RV strains/strain rates, whereas the PC rats exhibited reduced strains/strain rates (26–48% lower than sham). Of the strain parameters, longitudinal strain and strain rate exhibited the highest correlations to LVEDP and lung weight (rho = 0.65–0.72, P < 0.001). Basal longitudinal strain was most closely associated with signs of pulmonary congestion and indexes of RV remodeling. Longitudinal RV strain had higher area under the curve than ejection fraction for detecting subtle RV dysfunction (area under the curve = 0.85 vs. 0.67). In conclusion, we show for the first time that global and regional RV myocardial strain can be measured robustly in rodents. Reduced RV strain was closely associated with indexes of pulmonary congestion and molecular markers of RV remodeling.

NEW & NOTEWORTHY Global and regional right ventricular myocardial strain can be measured with high reproducibility and low interobserver variability in rodents using tissue phase mapping MRI. Reduced right ventricular strain was associated with indexes of pulmonary congestion and molecular markers of right ventricular remodeling. Regional strain in the basal myocardium was considerably higher than in the apical myocardium.

Medical Therapies for Heart Failure With Preserved Ejection Fraction

Current cardiovascular pharmacotherapy targets maladaptive overactivation of the renin-angiotensin-aldosterone system (RAAS), which occurs throughout the continuum of cardiovascular disease spanning from hypertension to heart failure with reduced ejection fraction. Over the past 16 years, 4 prospective, randomized, placebo-controlled clinical trials using candesartan, perindopril, irbesartan, and spironolactone in patients with heart failure with preserved ejection fraction (HFpEF) failed to demonstrate increased efficacy of RAAS blockade added to guideline-directed medical therapy. We reappraise these trials and their weaknesses, which precluded statistically significant findings. Recently, dual-acting RAAS blockade with sacubitril-valsartan relative to stand-alone valsartan failed to improve outcome in the PARAGON-HF trial (Efficacy and Safety of LCZ696 Compared with Valsartan, on Morbidity and Mortality in Heart Failure Patients With Preserved Ejection Fraction). The majority of patients with HFpEF experience hypertension, frequently with subclinical left ventricular dysfunction, contributed to by comorbidities such as coronary disease, diabetes mellitus, overweight, and atrial fibrillation. Contrasting the findings in HFpEF, trials evaluating RAAS blockade on either side of HFpEF on the cardiovascular continuum in patients with high-risk hypertension and heart failure with reduced ejection fraction, respectively, showed positive outcomes. We do not have a biologically plausible explanation for such divergent efficacy of RAAS blockade. Based on considerations of well-established clinical efficacy in hypertension and heart failure with reduced ejection fraction and the shortcomings of aforementioned clinical trials in HFpEF, we argue that RAAS blockers including MRAs (mineralocorticoid receptor antagonists; aldosterone antagonists) should be used in the treatment of patients with HFpEF.

The left ventricular ejection fraction: new insights into an old parameter

Accurate evaluation of cardiac function has become increasingly important as the treatment of cardiac disease has become more complex. At the same time, technological advances allow greater accuracy and precision in cardiac measurements. Measurement of left ventricular ejection fraction (LVEF) has been a pillar of cardiac evaluation. Several noninvasive modalities are available to assess LVEF; each has advantages and limitations. This review examines various modalities used to measure LVEF and focuses on the relative strengths and weaknesses of each modality. In some clinical settings, however, LVEF may be too insensitive to convey subtle changes in LV contractility. In certain clinical situations, use of LVEF may be an insufficient measure of left ventricular systolic function. Global longitudinal strain is one such parameter that has shown promise for detecting subtle reductions in left ventricular contractility in subjects with chemotherapy-induced cardiotoxicity.

Baseline Longitudinal Strain Predicts Recovery of Left Ventricular Ejection Fraction in Hospitalized Patients With Nonischemic Cardiomyopathy

Background

Heart failure (HF) with “recovered” ejection fraction (HFrecEF) is an emerging phenotype, but no tools exist to predict ejection fraction (EF) recovery in acute HF. We hypothesized that indices of baseline cardiac structure and function predict HFrecEF in nonischemic cardiomyopathy and reduced EF.

Methods and Results

We identified a nonischemic cardiomyopathy cohort with EF<40% during the first HF hospitalization (n=166). We performed speckle‐tracking echocardiography to measure longitudinal, circumferential, and radial strain, and the average of these measures (myocardial systolic performance). HFrecEF was defined as follow‐up EF ≥40% and ≥10% improvement from baseline EF. Fifty‐nine patients (36%) achieved HFrecEF (baseline EF 26±7%; follow‐up EF 51±7%) within a median of 135 (interquartile range 58‐239) days after the first HF hospitalization. Baseline demographics, biomarker profiles, and comorbid conditions (except lower chronic kidney disease in HFrecEF) were similar between HFrecEF and persistent reduced‐EF groups. HFrecEF patients had smaller baseline left ventricular end‐systolic dimension (3.6 versus 4.8 cm; P<0.01), higher baseline myocardial systolic performance (9.2% versus 8.1%; P=0.02), and improved survival (adjusted hazard ratio 0.27, 95% confidence interval 0.11, 0.62). We found a significant interaction between baseline left ventricular end‐systolic dimension and absolute longitudinal strain. Among patients with left ventricular end‐systolic dimension >4.35 cm, higher absolute longitudinal strain (≥8%) was associated with HFrecEF (unadjusted odds ratio=3.9, 95% CI)confidence interval 1.2, 12.8). Incorporation of baseline indices of cardiac mechanics with clinical variables resulted in a predictive model for HFrecEF with c‐statistic=0.85.

Conclusions

Factors associated with achieving HFrecEF were specific to cardiac structure and indices of cardiac mechanics. Higher baseline absolute longitudinal strain is associated with HFrecEF among nonischemic cardiomyopathy patients with reduced EF and larger left ventricular dimensions.

Range Variability in CMR Feature Tracking Multilayer Strain across Different Stages of Heart Failure

Heart failure (HF) is associated with progressive ventricular remodeling and impaired contraction that affects distinctly various regions of the myocardium. Our study applied cardiac magnetic resonance (CMR) feature tracking (FT) to assess comparatively myocardial strain at 3 distinct levels: subendocardial (Endo-), mid (Myo-) and subepicardial (Epi-) myocardium across an extended spectrum of patients with HF. 59 patients with HF, divided into 3 subgroups as follows: preserved ejection fraction (HFpEF, N = 18), HF with mid-range ejection fraction (HFmrEF, N = 21), HF with reduced ejection fraction (HFrEF, N = 20) and a group of age- gender- matched volunteers (N = 17) were included. Using CMR FT we assessed systolic longitudinal and circumferential strain and strain-rate at Endo-, Myo- and Epi- levels. Strain values were the highest in the Endo- layer and progressively lower in the Myo- and Epi- layers respectively, this gradient was present in all the patients groups analyzed but decreased progressively in HFmrEF and further on in HFrEF groups. GLS decreased with the severity of the disease in all 3 layers: Normal > HFpEF > HFmrEF > HFrEF (Endo-: −23.0 ± 3.5 > −20.0 ± 3.3 > −16.4 ± 2.2 > −11.0 ± 3.2, p < 0.001, Myo-: −20.7 ± 2.4 > −17.5.0 ± 2.6 > −14.5 ± 2.1 > −9.6 ± 2.7, p < 0.001; Epi-: −15.7 ± 1.9 > −12.2 ± 2.1 > −10.6 ± 2.3 > −7.7 ± 2.3, p < 0.001). In contrast, GCS was not different between the Normal and HFpEF (Endo-: −34.5 ± 6.2 vs −33.9 ± 5.7, p = 0.51; Myo-: −21.9 ± 3.8 vs −21.3 ± 2.2, p = 0.39, Epi-: −11.4 ± 2.0 vs −10.9 ± 2.3, p = 0.54) but was, as well, markedly lower in the systolic heart failure groups: Normal > HFmrEF > HFrEF (Endo-: −34.5 ± 6.2 > −20.0 ± 4.2 > 12.3 ± 4.2, p < 0.001; Myo-: −21.9 ± 3.8 > −13.0 ± 3.4 > −8.0 ± 2.7. p < 0.001; Epi-: −11.4 ± 2.0 > −7.9 ± 2.3 > −4.5 ± 1.9. p < 0.001). CMR feature tracking multilayer strain assessment identifies large range differences between distinct myocardial regions. Our data emphasizes the importance of sub-endocardial myocardium for cardiac contraction and thus, its predilect role in imaging detection of functional impairment. CMR feature tracking offers a convenient, readily available, platform to evaluate myocardial contraction with excellent spatial resolution, rendering further details about discrete areas of the myocardium. Using this technique across distinct groups of patients with heart failure (HF), we demonstrate that subendocardial regions of the myocardium exhibit much higher strain values than mid-myocardium or subepicardial and are more sensitive to detect contractile impairment. We also show comparatively higher values of circumferential strain compared with longitudinal and a higher sensitivity to detect contractile impairment. A newly characterized group of patients, HF with mid-range ejection fraction (EF), shows similar traits of decompensation but has relatively higher strain values as patients with HF with reduced EF.

Feature-Tracking MRI Fractal Analysis of Right Ventricular Remodeling in Adults with Congenitally Corrected Transposition of the Great Arteries

Purpose

To assess a recently available technique for quantification of right ventricular (RV) trabeculae that is based on fractal analysis performed by using cardiac MRI feature tracking, in patients with congenitally corrected transposition of the great arteries (cc-TGA).

Materials and Methods

A total of 19 patients (eight men, 11 women; mean age, 35 years ± 10 [standard deviation]) with consecutive cc-TGA who underwent cardiac MRI were enrolled in the study. For analysis, patients were divided into two groups: six patients (four men, two women; mean age, 34 years ± 14) with an end-systolic RV volume index higher than 72 mL/m² (indicative of adverse RV remodeling) and 13 patients (four men, nine women; mean age, 36 years ± 9) in whom this index was lower than or equal to 72 mL/m² (indicative of adapted RV). The following outcomes were quantified in the midsection of the RV: fractional fractal dimension (FD) and diastolic FD, circumferential strain, and radial strain. Receiver operating characteristic (ROC) analysis was performed to determine the cutoff FD values for the detection of adverse RV remodeling. Correlations among fractional FD, diastolic FD, circumferential strain, and radial strain were calculated by using Pearson correlation coefficient (r) analysis.

Results

The following ROC values were identified for fractional and diastolic FD: cutoff, 0.09 and 1.39, respectively; area under the ROC curve, 0.95 and 0.68, respectively; sensitivity, 1.00 and 0.33, respectively; and specificity, 0.92 and 1.00, respectively. Fractional FD correlated with circumferential strain and radial strain (r = -0.70 and 0.69, respectively; P < .01), as did diastolic FD (r = 0.37 and -0.38, respectively; P < .05).

Conclusion

The fractional FD derived from cardiac MRI feature-tracking analysis correlates with adverse RV remodeling, including a changed strain pattern and trabeculae, in patients with cc-TGA.© RSNA, 2019.

Assessment of Biventricular Function by Three-Dimensional Speckle Tracking Echocardiography in Adolescents and Young Adults with Human Immunodeficiency Virus Infection: A Pilot Study

BACKGROUND

The purpose of the study was to assess biventricular parameters of wall deformation with three-dimensional speckle tracking echocardiography (3DSTE) in adolescents and young adults with human immunodeficiency virus (HIV) infection on antiretroviral therapy in order to detect a possible subclinical myocardial dysfunction.

METHODS

Twenty-one patients aged 12-39 years with HIV, 21 normal controls of the same age and sex, and 21 patients with idiopathic nonischemic dilated cardiomyopathy (DCM) were studied with 3DSTE. All HIV patients were stable in terms of HIV infection, with no history of heart disease or other chronic systemic disease except HIV infection, and were on highly active antiretroviral therapy with good immunological control. Standard echocardiographic measures of left ventricular (LV)-right ventricular (RV) function were assessed. 3D LV global longitudinal strain (GLS), circumferential strain, radial strain, and LV twist were calculated. Global area strain (GAS) was calculated by 3DSTE as percentage variation in surface area defined by the longitudinal and circumferential strain vectors. 3D RV global and free-wall longitudinal strain (FWLS) were obtained.

RESULTS

LV GLS and GAS were lower in HIV patients compared to normal controls (p = 0.002, and p = 0.01, respectively). There were no significant differences in LV ejection fractions between the groups. There was a weak positive correlation between LV GLS and age (r = 0.215, p = 0.034) and a weak negative correlation between LV GLS and nadir-CD4 T-cells count (r = 0.198, p = 0.043). DCM patients had more marked and widespread reduction in LV GLS and GAS compared to controls (p < 0.001), whereas in HIV patients LV strain impairment (p < 0.05) was more localized in basal and apical regions. RV FWLS was significantly reduced in HIV patients when compared with the control group (p = 0.03). No patient had pulmonary systolic pressure higher than 35 mm Hg.

CONCLUSIONS

3DSTE may help to identify HIV patients at high cardiovascular risk allowing early detection of biventricular dysfunction in the presence of normal LV ejection fraction and in the absence of pulmonary hypertension. LV strain impairment in HIV patients is less prominent and widespread compared to DCM patients.

Association of Left Ventricular Global Longitudinal Strain With Asymptomatic Severe Aortic Stenosis: Natural Course and Prognostic Value

Importance

The optimal timing to operate in patients with asymptomatic severe aortic stenosis (AS) remains controversial. Left ventricular global longitudinal strain (LV GLS) may help to identify patients who might benefit from undergoing earlier aortic valve replacement.

Objective

To investigate the prevalence of impaired LV GLS, the natural course of LV GLS, and its prognostic implications in patients with asymptomatic severe AS with preserved left ventricular ejection fraction (LVEF).

Design, Setting, and Participants

This registry-based study included the institutional registries of 3 large tertiary referral centers and 220 patients with asymptomatic severe AS and preserved LVEF (>50%) who were matched for age and sex with 220 controls without structural heart disease. The echocardiograms of patients and controls were performed between 1998 and 2017.

Exposures

Both clinical and echocardiographic data were assessed retrospectively. Severe AS was defined by an indexed aortic valve area less than 0.6 cm2/m2. Left ventricular global longitudinal strain was evaluated on transthoracic echocardiography using speckle tracking imaging.

Main Outcomes and Measures

The prevalence of impaired LV GLS, the natural course of LV GLS, and the association of impaired LV GLS with symptom onset and the need for aortic valve intervention.

Results

Two hundred twenty patients (mean [SD] age, 68 [13] years; 126 men [57%]) were included. Despite comparable LVEF, LV GLS was significantly impaired in patients with asymptomatic severe AS compared with age- and sex-matched controls without AS (mean [SD] LV GLS, -17.9% [2.5%] vs -19.6% [2.1%]; P < .001). After a median follow-up of 12 (interquartile range, 7-23) months, mean (SD) LV GLS significantly deteriorated (-18.0% [2.6%] to -16.3% [2.8%]; P < .001) while LVEF remained unchanged. Patients with impaired LV GLS at baseline (>-18.2%) showed a higher risk for developing symptoms (P = .02) and needing aortic valve intervention (P = .03) at follow-up compared with patients with more preserved LV GLS (≤-18.2%).

Conclusions and Relevance

Subclinical myocardial dysfunction that is characterized by impaired LV GLS is often present in patients with asymptomatic severe AS with preserved LVEF. Left ventricular global longitudinal strain further deteriorates over time and impaired LV GLS at baseline is associated with an increased risk for progression to the symptomatic stage and the need for aortic valve intervention.

Changes in Cardiac Morphology and Function in Individuals With Diabetes Mellitus: The UK Biobank Cardiovascular Magnetic Resonance Substudy

BACKGROUND

Diabetes mellitus (DM) is associated with increased risk of cardiovascular disease. Detection of early cardiac changes before manifest disease develops is important. We investigated early alterations in cardiac structure and function associated with DM using cardiovascular magnetic resonance imaging.

METHODS

Participants from the UK Biobank Cardiovascular Magnetic Resonance Substudy, a community cohort study, without known cardiovascular disease and left ventricular ejection fraction ≥50% were included. Multivariable linear regression models were performed. The investigators were blinded to DM status.

RESULTS

A total of 3984 individuals, 45% men, (mean [SD]) age 61.3 (7.5) years, hereof 143 individuals (3.6%) with DM. There was no difference in left ventricular (LV) ejection fraction (DM versus no DM; coefficient [95% CI]: -0.86% [-1.8 to 0.5]; P=0.065), LV mass (-0.13 g/m2 [-1.6 to 1.3], P=0.86), or right ventricular ejection fraction (-0.23% [-1.2 to 0.8], P=0.65). However, both LV and right ventricular volumes were significantly smaller in DM, (LV end-diastolic volume/m2: -3.46 mL/m2 [-5.8 to -1.2], P=0.003, right ventricular end-diastolic volume/m2: -4.2 mL/m2 [-6.8 to -1.7], P=0.001, LV stroke volume/m2: -3.0 mL/m2 [-4.5 to -1.5], P<0.001; right ventricular stroke volume/m2: -3.8 mL/m2 [-6.5 to -1.1], P=0.005), LV mass/volume: 0.026 (0.01 to 0.04) g/mL, P=0.006. Both left atrial and right atrial emptying fraction were lower in DM (right atrial emptying fraction: -6.2% [-10.2 to -2.1], P=0.003; left atrial emptying fraction:-3.5% [-6.9 to -0.1], P=0.043). LV global circumferential strain was impaired in DM (coefficient [95% CI]: 0.38% [0.01 to 0.7], P=0.045).

CONCLUSIONS

In a low-risk general population without known cardiovascular disease and with preserved LV ejection fraction, DM is associated with early changes in all 4 cardiac chambers. These findings suggest that diabetic cardiomyopathy is not a regional condition of the LV but affects the heart globally.

Myocardial global longitudinal strain: An early indicator of cardiac interstitial fibrosis modified by spironolactone, in a unique hypertensive rat model

OBJECTIVES

Is global longitudinal strain (GLS) a more accurate non-invasive measure of histological myocardial fibrosis than left ventricular ejection fraction (LVEF) in a hypertensive rodent model.

BACKGROUND

Hypertension results in left ventricular hypertrophy and cardiac dysfunction. Speckle-tracking echocardiography has emerged as a robust technique to evaluate cardiac function in humans compared with standard echocardiography. However, its use in animal studies is less clearly defined.

METHODS

Cyp1a1Ren2 transgenic rats were randomly assigned to three groups; normotensive, untreated hypertensive or hypertensive with daily administration of spironolactone (human equivalent dose of 50 mg/day). Cardiac function and interstitial fibrosis development were monitored for three months.

RESULTS

The lower limit of normal LVEF was calculated to be 75%. After three months hypertensive animals (196±21 mmHg systolic blood pressure (SBP)) showed increased cardiac fibrosis (8.8±3.2% compared with 2.4±0.7% % in normals), reduced LVEF (from 81±2% to 67±7%) and impaired myocardial GLS (from -17±2% to -11±2) (all p<0.001). Myocardial GLS demonstrated a stronger correlation with cardiac interstitial fibrosis (r2 = 0.58, p<0.0001) than LVEF (r2 = 0.37, p<0.006). Spironolactone significantly blunted SBP elevation (184±15, p<0.01), slowed the progression of cardiac fibrosis (4.9±1.4%, p<0.001), reduced the decline in LVEF (72±4%, p<0.05) and the degree of impaired myocardial GLS (-13±1%, p<0.01) compared to hypertensive animals.

CONCLUSIONS

This study has demonstrated that, myocardial GLS is a more accurate non-invasive measure of histological myocardial fibrosis compared to standard echocardiography, in an animal model of both treated and untreated hypertension. Spironolactone blunted the progression of cardiac fibrosis and deterioration of myocardial GLS.

Atrioventricular mechanical coupling and major adverse cardiac events in female patients following acute ST elevation myocardial infarction

BACKGROUND

Sex-specific outcome data following myocardial infarction (MI) are inconclusive with some evidence suggesting association of female sex and increased major adverse cardiac events (MACE). Since mechanistic principles remain elusive, we aimed to quantify the underlying phenotype using cardiovascular magnetic resonance (CMR) quantitative deformation imaging and tissue characterisation.

METHODS

In total, 795 ST-elevation MI patients underwent post-interventional CMR imaging. Feature-tracking (CMR-FT) was performed in a blinded core-laboratory. Left ventricular function was quantified using ejection fraction (LVEF) and global longitudinal/circumferential/radial strains (GLS/GCS/GRS). Left atrial function was assessed by reservoir (εs), conduit (εe) and booster-pump strains (εa). Tissue characterisation included infarct size, microvascular obstruction and area at risk. Primary endpoint was the occurrence of MACE within 1 year.

RESULTS

Female sex was associated with increased MACE (HR 1.96, 95% CI 1.13-3.42, p = 0.017) but not independently of baseline confounders (p = 0.526) with women being older, more often diabetic and hypertensive (p < 0.001) and of higher Killip-class (p = 0.010). Tissue characterisation was similar between sexes. Women showed impaired atrial (εs p = 0.011, εe p < 0.001) but increased systolic ventricular mechanics (GLS p = 0.001, LVEF p = 0.048). While atrial and ventricular function predicted MACE in men only LV GLS and GCS were associated with MACE in women irrespective of confounders (GLS p = 0.036, GCS p = 0.04).

CONCLUSION

In men ventricular systolic contractility is impaired and volume assessments precisely stratify elevated risks. In contrast, women experience reduced atrial but increased ventricular systolic strain. This may reflect ventricular diastolic failure with systolic compensation, which is independently associated with MACE adding incremental value to sex-specific prognosis evaluation.

Longitudinal strain measured by two-dimensional speckle tracking echocardiography to evaluate left ventricular function in patients with myocardial bridging of the left anterior descending coronary artery

OBJECTIVES

Myocardial bridging (MB) can cause myocardial ischemia, myocardial infarction, or even sudden cardiac death. We aimed to evaluate the left ventricular function in patients with MB of the left anterior descending coronary artery (LAD) using longitudinal strain (LS) measured by two-dimensional speckle tracking echocardiography.

METHODS

We enrolled 46 subjects with MB in the LAD diagnosed by coronary angiography. Patients were categorized into two groups according to the severity of tunneled artery stenosis: <50% as group I (23 patients) and ≥50% as group II (23 patients). Twenty-five gender- and age-matched subjects without MB confirmed by coronary angiography or with normal results on treadmill exercise test were included as controls. Two-dimensional strain software was applied to measure the territories systolic average peak LS of the LAD coronary artery (LAD-TPLS), right coronary artery (RCA-TPLS), and left circumflex coronary artery (LCX-TPLS) and to measure the global systolic peak LS of left ventricle (LV-GPLS).

RESULTS

The ratio of mitral peak early (E) and late (A) filling velocity (E/A) and the average mitral annular velocity (e') were lower, and the mitral E/e' ratio was higher in group II than in group I and controls (P < 0.05). LV-GPLS and LAD-TPLS were significantly less negative in group II than in group I and controls (LV-GPLS: -19.77 ± 1.60% vs -21.10 ± 1.91% and -21.76 ± 1.23%; LAD-TPLS: -19.24 ± 2.22% vs -22.00 ± 2.22% and -22.74 ± 1.82%, P < 0.001). The systolic compression severity of the tunneled artery was significantly correlated with LAD-TPLS (r = -0.56, P < 0.001), but less strongly correlated with LV-GPLS (r = -0.40, P < 0.05). The area under the curves of LAD-TPLS was larger than that of LV-GPLS; a cutoff value for LAD-TPLS of -21.68% had 91.3% sensitivity and 73.9% specificity for detection of ≥50% of the tunneled artery stenosis.

CONCLUSIONS

In patients with ≥50% systolic narrowing of the tunneled artery, left ventricular systolic function and diastolic function were impaired, and the LAD-TPLS is an excellent predictor of ≥50% systolic narrowing of the tunneled artery in patients with MB of the LAD.