Comparative left ventricular mechanical deformation in acute apical variant stress cardiomyopathy and acute anterior myocardial infarction utilizing 2-dimensional longitudinal strain imaging.

AIMS: Despite three decades of study, it is still challenging to discriminate acute apical variant stress cardiomyopathy (AVSCM) from acute left anterior descending-myocardial infarction (LAD-MI) at the time of presentation. A biomarker or practical imaging modality that can differentiate these two entities is highly desirable. Our objective was to characterize left ventricular (LV) mechanical deformation using 2-dimensional (2D) echocardiographic strain imaging in an attempt to discriminate AVSCM from LAD-MI at presentation. METHODS AND RESULTS: We studied 108 women (60 AVSCM, 48 ST segment elevation LAD-MI). All underwent echocardiography within 48 hours of presentation. 2D longitudinal strain (LS) from an 18-segment LV model was performed, with global LS (GLS) taken as the average of all 18 segments. GLS was abnormal, but did not differentiate AVSCM from LAD-MI. Mean LS of the basal and mid-anterior, basal, and mid-anteroseptum segments were significantly lower in LAD-MI vs AVSCM group (-14 ± 9% vs -20 ± 8%; -11 ± 7% vs -14 ± 6%; -9 ± 8% vs -14 ± 8%; -9 ± 7% vs -13 ± 5%, respectively, all P ≤ .05). Mean LS of the basal inferior and inferolateral segments was significantly higher in the LAD-MI vs. AVSCM group (-19 ± 9% vs -13 ± 7%; -23 ± 11% vs -18 ± 7%, respectively, all P ≤ .05). Using ROC curve analysis, segmental strain ratio of average basal inferior and inferolateral segments LS to average mid- and basal anterior and anteroseptum segments LS of ≥1.58 was 90% specific for LAD-MI [area under the curve (AUC) 0.87; P < .001]. CONCLUSION: Longitudinal strain patterns are useful in discriminating AVSCM from LAD-MI patients at presentation and may be valuable in stratifying patients for invasive evaluation.

Vector velocity imaging echocardiography to study the effects of submassive pulmonary embolism on the right atrium.

OBJECTIVES: To assess the effects of submassive pulmonary embolism (SMPE) on right atrial (RA) anatomy and function. BACKGROUND: Right ventricular dysfunction (RVD) is associated with adverse outcomes in SMPE. However, the effects of SMPE on the structure and function of the RA have received much less attention. METHODS: Fifty patients with SMPE documented by CT angiography (SMPE group) and evidence of RVD on two-dimensional echocardiography were retrospectively identified and compared to 50 controls (control group). Both RA and RV areas, volumes and fractional area change (FAC) were measured. Pulmonary artery systolic pressures were estimated. RA and RV longitudinal strains were obtained using vector velocity imaging (VVI). RESULTS: Compared with controls, RA and RV FACs were significantly reduced and associated with higher chamber volumes in the SMPE group. Global longitudinal RA strain was reduced in the SMPE group (29% + 11% vs 55% + 16%; P < .01), as was global RV longitudinal strain (-12% + 5% vs -20% + 5%, P < .01), when compared to the controls. A linear relationship existed between RV and RA strain in both groups; however, the curve was shifted downward among those with SMPE. Furthermore, ROC curve analysis suggests RA area performs better than RV area as a marker of SMPE. CONCLUSIONS: RA structure and function are adversely affected in SMPE, similar to the effects observed in RV. Lower RA strain appears to be a novel quantitative indicator of SMPE, and RA area may be a more sensitive marker of this condition and may provide additional prognostic information in this condition.

The presbycardia phenotype: Cardiac remodeling and valvular degeneration in nonagenarians.

BACKGROUND: Nonagenarians (NON) are a growing segment of the population and have a high prevalence of cardiac disease. Many findings encountered on their echocardiograms are also found in younger individuals with valvular or myocardial disease. Therefore, the purpose of this study was to describe this distinct echocardiographic phenotype. METHODS: We identified our study population by querying our echo database to identify unique septuagenarians (SEPT) and nonagenarians (NON) who underwent a transthoracic echocardiogram (TTE) from January 1, 2010 to December 31, 2014. Exclusion criteria were LVEF < 50%, any akinetic wall segment, aortic stenosis, moderate-severe AR and/or severe MR, coronary revascularization within 60 days of study echo, and prior valve surgery. RESULTS: The mean age of SEPT was 73.0 ± 2.0 and NON was 92.0 ± 2.1 (P < 0.001). There was no gender difference between groups. NON had significantly smaller LV end-diastolic diameters than SEPT (41.6 ± 5.7 mm vs 48.0 ± 7.0 mm, P < 0.001). NON had a greater relative wall thickness (0.51 ± 0.10 vs 0.40 ± 0.08, P < 0.001) and more frequently had concentric remodeling or hypertrophy. NON had higher E/Ea ratios and estimated LA pressures (P < 0.01). 48% of NON had moderate-severe mitral annular calcification compared to 25.0% of SEPT (P < 0.01). CONCLUSIONS: Herein, we provide the first comprehensive echocardiographic description of 'presbycardia'; concentric LVH, asymmetric septal hypertrophy, mitral and aortic valve calcification, and increased epicardial fat thickness. This pattern of findings may be increasingly seen as the population ages.

Computer-assisted image processing 12 lead ECG model to diagnose hyperkalemia.

BACKGROUND: We sought to develop an improved 12 lead ECG model to diagnose hyperkalemia by use of traditional and novel parameters. METHODS: We retrospectively analyzed ECGs in consecutive hyperkalemic patients (serum potassium (K)>5.3mEq/L) by blinded investigators with normokalemic ECGs as internal controls. Potassium levels were modeled using general linear mixed models followed by refit with standardized variables. Optimum sensitivity and specificity were determined using cut point analysis of ROC-AUC. RESULTS: The training set included 236 ECGs (84 patients) and validation set 97 ECGs (23 patients). Predicted K=(5.2354)+(0.03434*descending T slope)+(-0.2329*T width)+(-0.9652*reciprocal of new QRS width>100msec). ROC-AUC in the validation set was 0.78 (95% CI 0.69-0.88). Maximum specificity of the model was 84% for K>5.91 with sensitivity of 63%. CONCLUSION: ECG model incorporating T-wave width, descending T-wave slope and new QRS prolongation improved hyperkalemia diagnosis over traditional ECG analysis.

Mitoxantrone-Induced Cardiotoxicity in Acute Myeloid Leukemia-A Velocity Vector Imaging Analysis.

BACKGROUND: The purpose of this investigation was to: (1) determine incidence and predictors of mitoxantrone-induced early cardiotoxicity and (2) study left ventricular mechanics before and after receiving mitoxantrone. METHOD AND RESULTS: We retrospectively analyzed 80 subjects diagnosed with acute myeloid leukemia (AML) who underwent chemotherapy with bolus high-dose mitoxantrone. Echocardiographic measurements were taken at baseline and at a median interval of 55 days after receiving mitoxantrone. Thirty-five (44%) of the patients developed clinically defined early cardiotoxicity, 29 (36%) of which developed heart failure. There was a significant decrease in the ejection fraction (EF) not only in the cardiotoxicity group (17.6 ± 14.8%, P < 0.001) but also in the noncardiotoxicity group (5.3 ± 8.4%, P < 0.001). Decrease in global longitudinal strain (GLS) (-3.7 ± 4.5, P < 0.001 vs. -2.4 ± 4.3, P = 0.01) and global circumferential strain (GCS) (-5.6 ± 9, P = 0.003 vs. -5.3 ± 8.7, P < 0.001) was significant in both the cardiotoxicity and noncardiotoxicity group, respectively. A multivariate model including baseline left ventricular end-systolic diameter, baseline pre-E/A ratio, and baseline pre-E/e' ratio was found to be the best-fitted model for prediction of mitoxantrone-induced early clinical cardiotoxicity. CONCLUSION: High-dose mitoxantrone therapy is associated with an excellent remission rate but with a significantly increased risk of clinical and subclinical early cardiotoxicity and heart failure. Mitoxantrone-induced systolic dysfunction is evident from reduction in EF, increase in Tei index, and significant reduction in GLS and GCS. Baseline impaired ventricular relaxation evident from higher E/e' ratio and lower E/A ratio independently predicts increased risk of mitoxantrone-induced early cardiotoxicity.

Systolic and diastolic mechanics in stress cardiomyopathy.

BACKGROUND: Stress cardiomyopathy (SCM) is a peculiar form of reversible left ventricular dysfunction seen predominantly in women and occurs in response to emotional or physical stress. Because dysfunction in SCM is reversible and that of acute myocardial infarction (MI) is not, we hypothesized that these fundamental mechanistic differences between SCM and MI would be associated with different systolic and diastolic properties. METHODS AND RESULTS: We examined 3 groups, all women: patients with SCM (n=24; mean age, 63±12 years), those with left anterior (LAD) ST-segment-elevation MI (n=36; mean age, 63±10 years), and referent control subjects (n=30; mean age, 62±8 years). All underwent angiography, ventriculography, and pressure measurements within 48 hours of presentation. Left ventricular volumes, diastolic pressures, and diastolic stiffness were higher in SCM and LAD MI patients than in control subjects but no different from each other. Similarly, left ventricular diastolic pressures and diastolic stiffness were elevated in the SCM and LAD MI groups compared with the control group. Left ventricular ejection fraction in SCM and LAD MI were 40.8±12.3% and 49.6±5.6%, respectively, versus 70.4±9.4% in control subjects (P<0.001), and stroke work less than half the value of control subjects. Indexes of contractility and ventricular-arterial coupling were similarly abnormal in SCM and LAD MI. CONCLUSIONS: SCM and LAD MI show severe diastolic dysfunction. At similar left ventricular volumes, their diastolic pressures are more than twice as high as in control subjects, and systolic dysfunction is equally reduced in SCM and LAD MI. Despite a completely different pathophysiology in terms of systolic and diastolic function, SCM is indistinguishable from acute LAD-territory MI.

Systolic pulmonary and hepatic vein flow reversal due to pacemaker-induced retrograde ventriculoatrial conduction.

Systolic pulmonary and hepatic vein flow reversals can typically be seen with severe atrioventricular (AV) valve regurgitation and during atrial fibrillation (AF). We report the case of a 67-year-old woman who presented with recent-onset exertional dyspnea. Her pacemaker was near end-of-life and reverted to a VVI mode from the preset DDDR mode. Electrocardiography demonstrated retrograde 1:1 ventriculoatrial (VA) conduction and spectral Doppler analysis revealed prominent systolic pulmonary and hepatic vein flow reversals. Symptoms, electrocardiogram (ECG) findings, and the spectral Doppler abnormalities resolved completely following a generator replacement and resumption of DDDR pacing.

Depressed atrial function in diastolic dysfunction: a speckle tracking imaging study.

BACKGROUND: Two-dimensional speckle tracking imaging (STI) has recently been applied to the study of left atrial (LA) reservoir function. We utilized STI to analyze LA function in diastolic dysfunction (DD), hypothesizing that LA strain abnormality is part of the pathogenesis of diastolic dysfunction. METHODS: We applied STI to 50 patients with Grade 1-2 DD, comparing these results to 100 normal controls. Complete Doppler analysis of filling was made using peak E, peak A and tissue Doppler e' velocities; E/e' was used as a surrogate for LA pressure and LA stiffness index was calculated. RESULTS: In analysis of covariance, adjusting for age and gender, compared with controls, DD patients had higher E/e', greater LA volume and greater LA stiffness, but lower E/A ratio and global LA strain. LA strain appears to be inversely related to LA volume, but not to other indices of LV diastolic function. In subgroup analysis, LA strain was significantly lower, and stiffness significantly higher in DD, even after correction for differences in LA volume and E/A ratio. Analysis of ROC curves suggests that abnormal LA strain is a better marker for diastolic dysfunction than LA enlargement. CONCLUSION: LA strain by STI is significantly reduced in early diastolic dysfunction and is related to higher LA stiffness and LA size. Reduction in LA strain is partially independent of LA volume; accordingly we hypothesize that reduced atrial strain indicates impaired atrial distensibility.

Insights Into the Standard Echocardiographic Views From Multimodality Imaging: Ventricles, Pericardium, Valves, and Atria.

The widespread use of cardiac computed tomography and cardiac magnetic resonance imaging in patients undergoing echocardiography presents an opportunity to correlate the images side by side. Accordingly, the aim of this report is to review aspects of the standard echocardiographic examination alongside similarly oriented images from the two tomographic imaging modalities. It is hoped that this exercise will enhance understanding of the structures depicted by echocardiography as they relate to other structures in the thorax. In addition to reviewing basic cardiac anatomy, the authors take advantage of these correlations with computed tomography and cardiac magnetic resonance imaging to better understand the issue of foreshortening, a common pitfall in transthoracic echocardiography. The authors also highlight an important role that three-dimensional echocardiography can potentially play in the future, especially as advances in image processing permit higher fidelity multiplanar reconstruction images.

Speckle echocardiographic left atrial strain and stiffness index as predictors of maintenance of sinus rhythm after cardioversion for atrial fibrillation: a prospective study.

BACKGROUND: Echocardiographic left atrial (LA) strain parameters have been associated with atrial fibrillation (AF) in prior studies. Our goal was to determine if strain measures [peak systolic longitudinal strain (LAS) and stiffness index (LASt)] changed after cardioversion (CV); and their relation to AF recurrence. METHODS AND RESULTS: 46 participants with persistent AF and 41 age-matched participants with no AF were recruited. LAS and LASt were measured before and immediately after CV using 2D speckle tracking imaging (2DSI). Maintenance of sinus rhythm was assessed over a 6-month follow up. Mean LAS was lower, and mean LASt higher, in participants with AF before CV as compared to control group (11.9±1.0 vs 35.7±1.7, p<0.01 and 1.31±0.17 vs 0.23±0.01, p<0.01, respectively). There was an increase in the mean LAS immediately after CV (11.9±1.0 vs 15.9±1.3, p<0.01), whereas mean LASt did not change significantly after CV (p=0.62). Although neither LAS nor LASt were independently associated with AF recurrence during the follow-up period, change in LAS after cardioversion (post-CV LAS-pre-CV LAS) was significantly higher among individuals who remained in sinus rhythm when compared to individuals with recurrent AF (3.6±1.1 vs 0.4±0.8, p=0.02). CONCLUSIONS: LAS and LASt differed between participants with and without AF, irrespective of the rhythm at the time of echocardiographic assessment. Baseline LAS and LASt were not associated with AF recurrence. However, change in LAS after CV may be a useful predictor of recurrent arrhythmia.

T-wave inversion and diastolic dysfunction in patients with electrocardiographic left ventricular hypertrophy.

OBJECTIVES: The aim of this study was to investigate if T-wave inversion (TWI) in the settings of electrocardiogram (ECG)-left ventricular hypertrophy (LVH) is associated with advanced diastolic dysfunction (DD) in subjects with preserved ejection fraction (EF). BACKGROUND: Animal studies suggested that an abnormal transmural repolarization sequence from endocardium to epicardium may contribute to DD. However, little is known about abnormal repolarization sequence and DD in humans. METHODS: We studied 231 patients with ECG-diagnosed LVH and with an EF of 50% or greater (measured within 6 months of the index ECG). T-wave inversion was assessed on leads I, aVL, V(4), V(5), or V(6). Diastolic dysfunction was defined based on echocardiographic estimation of the left atrial pressure. We used multiple logistic regression to estimate the odds ratio of DD comparing patients with TWI with those without TWI. RESULTS: The average age was 65.0 ± 14.2 years, and 61% were women. The mean EF was 61.8% ± 6.6%. Patients with TWIs were more likely to have coronary artery disease (P = .013) and diabetes (P = .007). There was a 5.6-fold increased odds of DD in patients with TWI compared with those without TWI in a model adjusting for sex, age, relative wall thickness, body mass index, hypertension, coronary artery disease, diabetes, hyperlipidemia, and smoking. When comparing different echocardiographic estimates of the left atrial pressure, patients with TWI displayed higher values for septal and lateral E/e', left atrial volume index, and right ventricular/right atrial peak systolic gradient (P < .01 for each parameter). CONCLUSIONS: T-wave inversion is associated with increased odds of DD in patients with ECG-LVH with preserved systolic function. The reversal of the normal sequence of repolarization manifested on the 12-lead ECG as TWI may be a factor to DD.

Use of beta-blockers and effects on heart rate and blood pressure post-acute coronary syndromes: are we on target?

BACKGROUND: beta-blockers have been shown to benefit patients after myocardial infarction by decreasing mortality, sudden cardiac death, and reinfarction. Although beta-blockers are recommended for all patients with acute coronary syndromes (ACS) without contraindications, a target heart rate (HR) is recommended only for patients with unstable angina/non ST-elevation myocardial infarction. A contemporary series documenting trends in beta-blocker usage and achieved HR and blood pressures (BP) is not available. The study objectives were to monitor trends in HR and BP in relation to beta-blocker use in a contemporary series of patients with ACS. METHODS: In this observational study, 300 consecutive patients with proven ACS had HR and BP values collected hourly from admission until hospital discharge and averaged at multiple intervals throughout hospital stay. Data on baseline demographic characteristics, beta-blocker doses, and titration schedules, procedures performed, cardiac regimens, concurrent medical issues, and contraindications to therapy were collected. RESULTS: Only 5.3% achieved an average HR of 50 to 60 beat/min throughout the hospital stay. Overall, the average HR was 74 beat/min and average BP was 115/64 mm Hg. Admission daily doses of metoprolol averaged 58 mg compared to discharge daily doses of 88 mg; only 52% of patients had dosage increases. CONCLUSIONS: Although effective levels of BP were maintained during hospitalization for an ACS, target HRs were generally not achieved. Future studies are needed to determine the relationship between treatment objectives and clinical outcomes in the present era of ACS management.

Are ejection fraction measurements by echocardiography and left ventriculography equivalent?

BACKGROUND: Left ventricular ejection fraction (EF) is an important parameter in the diagnosis and treatment of patients with coronary heart disease. Previous studies comparing echocardiography and contrast left ventriculography (CVG) for the measurement of EF have shown considerable variation in results, yet, in clinical practice, EF measurements are used interchangeably. The purpose of this study was to assess the concordance between echocardiography and CVG for the determination of EF in routine clinical practice and to identify factors associated with variation in test results. METHODS: We reviewed the medical records of 5,385 patients hospitalized for acute myocardial infarction between 1997 and 2005 as part of a community-based surveillance project. Of these, 741 patients had EF measurements recorded by both echocardiography and CVG during hospitalization. RESULTS: While good correlation (r = 0.73) and no systematic bias were noted between the measurement of EF by echocardiogram compared to CVG, there was wide variation between the 2 methods for any given patient. In approximately one third of patients with acute myocardial infarction, the measurement of EF by echocardiography and CVG differed by >10 points, while in approximately 1 in 20 patients, EF measurements by echocardiography and CVG differed by >20 points. The number of days between tests to measure EF, level of EF, temporal order of EF testing, and patient-related factors made only a minor contribution to the variation in test results. CONCLUSIONS: Our results demonstrate that, in routine clinical practice, EF determinations obtained by echocardiography and CVG may vary widely, with potentially important clinical implications.

Trends in the use of echocardiography and left ventriculography to assess left ventricular ejection fraction in patients hospitalized with acute myocardial infarction.

BACKGROUND: Although current guidelines strongly recommend the measurement of ejection fraction (EF) in all patients hospitalized with acute myocardial infarction (AMI), there are limited data available describing trends in the use of diagnostic modalities to assess EF in these patients. The purpose of this study was to evaluate trends in the use of ventriculography and echocardiography to measure EF in a community sample of patients hospitalized with AMI. METHODS: The medical records of 5,380 residents of the Worcester (MA) metropolitan area hospitalized with AMI at 11 greater Worcester medical centers between 1997 and 2005 were reviewed. RESULTS: Between 1997 and 2005, the proportion of patients hospitalized with AMI undergoing measurement of EF by both ventriculography and echocardiography increased from 11% to 18%, whereas the percentage of patients who did not receive an evaluation of EF by either modality decreased from 37% to 27%. The percentage of patients undergoing measurement of EF by ventriculography alone increased from 14% to 20%, whereas the percentage of patients undergoing measurement of EF by echocardiography alone remained stable at 37%. In 1997, echocardiography was performed before ventriculography in approximately two thirds of hospitalized patients, whereas in 2005, ventriculography was performed before echocardiography in approximately two thirds of patients with AMI. CONCLUSIONS: The use of left ventriculography and the concurrent use of both ventriculography and echocardiography to assess EF in patients with AMI are increasing. Although the proportion of patients who do not have their EF assessed has declined during recent years, many still do not receive a determination of their EF.

Is Left Ventricular Global Longitudinal Strain by Two-Dimensional Speckle Tracking Echocardiography in Sepsis Cardiomyopathy Ready for Prime Time Use in the ICU?

Myocardial deformation imaging (strain imaging) is a technique to directly quantify the extent of myocardial contractility and overcomes several of the limitations of ejection fraction. The application of the most commonly used strain imaging method; speckle-tracking echocardiography to patients with sepsis cardiomyopathy heralds an exciting development to the field. However; the body of evidence and knowledge on the utility, feasibility and prognostic value of left ventricular global longitudinal strain in sepsis cardiomyopathy is still evolving. We conducted a review of literature on utility of left ventricular global longitudinal strain in sepsis cardiomyopathy. We discuss the role of left ventricular global longitudinal strain in mortality prediction, utility and limitations of the technique in the context of sepsis cardiomyopathy.

Changing trends in the evaluation of ejection fraction in patients hospitalized with acute myocardial infarction: the Worcester Heart Attack Study.

BACKGROUND: Extent of left ventricular dysfunction in patients with acute myocardial infarction (AMI) is an important predictor of subsequent morbidity and mortality. It is unclear, however, how often ejection fraction (EF) findings are evaluated in the setting of AMI, and the characteristics of patients who do not have their EF evaluated, particularly from the more generalizable perspective of a population-based investigation. PURPOSE: The purpose of this study was to examine nearly 3 decade long trends (1975-2003) in the evaluation of EF in patients admitted with confirmed AMI (n = 12,760) to all greater Worcester (Massachusetts) hospitals during 14 annual periods. RESULTS: The percentage of patients undergoing evaluation of EF before hospital discharge increased substantially between 1975 (4%) and 2003 (73%). Despite these encouraging trends, approximately one quarter of patients in our most recent study year did not receive an EF evaluation. In the mid-1970s through mid-1980s, radionuclide ventriculography was typically used to assess EF, whereas echocardiography was most often used to evaluate EF during more recent periods. Predictors of not undergoing an evaluation of cardiac function included older age, shorter length of hospital stay, code status limitations, dying during hospitalization, Medicare insurance, several comorbidities, and a recent non-Q-wave myocardial infarction. CONCLUSIONS: The results of this community-wide study suggest that a considerable proportion of patients with AMI fail to have their EF evaluated. Efforts remain needed to optimize the use of cardiac imaging studies and link the results of these studies to improved patient outcomes.