Abnormal Regional Left Ventricular Systolic and Diastolic Function in Patients With Coronary Artery Disease Undergoing Percutaneous Coronary Intervention

Insight into different phenotypic presentations of heart failure with preserved ejection fraction

Heart failure (HF) with preserved ejection fraction (HFpEF) accounts for half of all HF diagnoses, and its prevalence is increasing at an alarming rate. Lately, it has been recognized as a clinical syndrome due to diverse underlying etiology and pathophysiological mechanisms. The classic echocardiographic features of HFpEF have been well described as preserved ejection fraction (≥50%), left ventricular hypertrophy, and left atrial enlargement. However, echocardiography can play a key role in identifying the principal underlying mechanism responsible for HFpEF in the individual patient. The recognition of different phenotypic presentations of HFpEF (infiltrative, metabolic, genetic, and inflammatory) can assist the clinician in tailoring the appropriate management, and offer prognostic information. The goal of this review is to highlight several key phenotypes of HFpEF and illustrate the classic clinical scenario and echocardiographic features of each phenotype with real patient cases.

Excimer laser coronary angioplasty versus manual aspiration thrombectomy in patients with ST-segment elevation myocardial infarction: analyzed by nuclear scintigraphy

Clinical outcomes concerning the efficacy of excimer laser coronary angioplasty (ELCA) in real-world cases of acute myocardial infarction (MI) are limited. We evaluated and compared the impact of ELCA with manual aspiration thrombectomy on myocardial salvage and left ventricular (LV) systolic/diastolic function in patients with ST-segment elevation MI (STEMI) using nuclear scintigraphy.  We enrolled 143 consecutive patients with STEMI treated with ELCA (63 patients) or manual aspiration thrombectomy (80 patients) between September 2016 and December 2020 in a single-center hospital. We evaluated the peak creatine kinase (CK)/ creatine kinase-myocardial band (CK-MB) levels and performed single-photon emission computed tomography (SPECT) analyses with Quantitative Gated SPECT and Quantitative Perfusion SPECT (Auto QUANT 7.2) at 3-10 days using ¹²³I-BMIPP and 3 months following percutaneous coronary intervention using ^99mTc-tetrofosmin to evaluate myocardial salvage and LV systolic/diastolic function. No significant difference was observed in the patient and periprocedural characteristics. Peak CK-MB level was significantly different between the groups (ELCA group, 190.0 [70.5-342.0] IU/L vs. aspiration group, 256.5 [157.0-354.8] IU/L, p = 0.047). Although no significant difference was observed in myocardial salvage, significant improvement in the LV ejection fraction (14.1 [6.2-19.8]% vs. 9.5 [3.9-15.3]%, respectively, p = 0.018) and peak emptying rate (-0.54 [-1.02- (-0.27)] mL/s vs. -0.38 [-0.76- (-0.05)] mL/s, respectively, p = 0.017) were detected. ELCA could suppress the myocardial deviation enzymes and potentially improve systolic function compared to manual aspiration thrombectomy in patients with STEMI.

Coronary Artery Disease and Heart Failure With Preserved Ejection Fraction: The ARIC Study

Background Whether coronary artery disease (CAD) is a significant risk factor for heart failure (HF) with preserved ejection fraction (HFpEF) is unclear. Methods and Results Among 9902 participants in the ARIC (Atherosclerosis Risk in Communities) study, we assessed the association of incident CAD with subsequent incident HFpEF (left ventricular ejection fraction [≥50%]) and HF with reduced ejection fraction (HFrEF; left ventricular ejection fraction <50%) using survival models with time-updated variables. We also assessed the extent to which echocardiographic correlates of prevalent CAD account for the relationship between CAD and incident HFpEF. Over 13-year follow-up, incident CAD developed in 892 participants and 178 subsequently developed HF (86 HFrEF, 71 HFpEF). Incident HFrEF and HFpEF risk were both greatest early after the CAD event. At >1 year post-CAD event, adjusted incidence of HFrEF and HFpEF were similar (7.2 [95% CI, 5.2-10.0] and 6.7 [4.8-9.2] per 1000 person-years, respectively) and CAD remained predictive of both (HFrEF: hazard ratio, 2.76 [95% CI, 1.99-3.84]; HFpEF: 1.85 [1.35-2.54]) after adjusting for demographics and common comorbidities. Among 4779 HF-free participants at Visit 5 (2011-2013), the 490 with prevalent CAD had lower left ventricular ejection fraction and higher left ventricular mass index, E/e', and left atrial volume index (all P<0.01). The association of prevalent CAD with incident HFpEF post-Visit 5 was not significant after adjusting for echocardiographic measures, with the greatest attenuation observed for left ventricular diastolic function. Conclusions CAD is a significant risk factor for incident HFpEF after adjustment for demographics and common comorbidities. This relationship is partially accounted for by echocardiographic alterations, particularly left ventricular diastolic function.

Impact of Pulse Wave Velocity and Parameters Reflecting Android Type Fat Distribution on Left Ventricular Diastolic Dysfunction in Patients with Chronic Coronary Syndromes

Background: Left ventricular diastolic dysfunction (LVDD) is caused by a decreased left ventricle relaxation and is associated with an increased risk of symptomatic heart failure (HF) and excessive mortality. Aim: To evaluate the frequency and factors related to LVDD in the population with chronic coronary syndromes (CCS). Methods: 200 patients (mean age 63.18 ± 8.12 years, 75.5% male) with CCS were included. LVDD was diagnosed based on the recent echocardiography guidelines. Results: LVDD was diagnosed in 38.5% of CCS population. From the studied factors, after adjustment for age, sex, and N-terminal pro-brain natriuretic peptide (NT-proBNP), LVDD associated positively with android/gynoid (A/G) fat mass ratio, left ventricular mass index (LVMI), and negatively with Z-score and left ventricular ejection fraction (LVEF). In stepwise backward logistic regression analysis, the strongest factors associated with LVDD were pulse wave velocity value, handgrip strength and waist to hip ratio (WHR). Conclusions: LVDD is common among CCS patients and it is associated with parameters reflecting android type fat distribution regardless of NT-proBNP and high-sensitivity troponin T concentrations. Deterioration in diastolic dysfunction is linked with increased aortic stiffness independently of age and sex. Further studies evaluating the effects of increasing physical fitness and lowering abdominal fat accumulations on LVDD in CCS patients should be considered.

Empagliflozin Ameliorates Diastolic Dysfunction and Left Ventricular Fibrosis/Stiffness in Nondiabetic Heart Failure: A Multimodality Study

OBJECTIVES

The purpose of this study was to investigate the effect of empagliflozin on diastolic function in a nondiabetic heart failure with reduced ejection fraction (HFrEF) scenario and on the pathways causing diastolic dysfunction.

BACKGROUND

This group demonstrated that empagliflozin ameliorates adverse cardiac remodeling, enhances myocardial energetics, and improves left ventricular systolic function in a nondiabetic porcine model of HF. Whether empagliflozin also improves diastolic function remains unknown. Hypothetically, empagliflozin would improve diastolic function in HF mediated both by a reduction in interstitial myocardial fibrosis and an improvement in cardiomyocyte stiffness (titin phosphorylation).

METHODS

HF was induced in nondiabetic pigs by 2-h balloon occlusion of proximal left anterior descending artery. Animals were randomized to empagliflozin or placebo for 2 months. Cardiac function was evaluated with cardiac magnetic resonance (CMR), 3-dimensional echocardiography, and invasive hemodynamics. In vitro relaxation of cardiomyocytes was studied in primary culture. Myocardial samples were obtained for histological and molecular evaluation. Myocardial metabolite consumption was analyzed by simultaneous blood sampling from coronary artery and coronary sinus.

RESULTS

Despite similar initial ischemic myocardial injury, the empagliflozin group showed significantly improved diastolic function at 2 months, assessed by conventional echocardiography (higher e' and color M-mode propagation velocity, lower E/e' ratio, myocardial performance Tei index, isovolumic relaxation time, and left atrial size), echocardiography-derived strain imaging (strain imaging diastolic index, strain rate at isovolumic relaxation time and during early diastole, and untwisting), and CMR (higher peak filling rate, larger first filling volume). Invasive hemodynamics confirmed improved diastolic function with empagliflozin (better peak LV pressure rate of decay (-dP/dt), shorter Tau, lower end-diastolic pressure-volume relationship (EDPVR), and reduced filling pressures). Empagliflozin reduced interstitial myocardial fibrosis at the imaging, histological and molecular level. Empagliflozin improved nitric oxide signaling (endothelial nitric oxide synthetase [eNOS] activity, nitric oxide [NO] availability, cyclic guanosine monophosphate (cGMP) content, protein kinase G [PKG] signaling) and enhanced titin phosphorylation (which is responsible for cardiomyocyte stiffness). Indeed, isolated cardiomyocytes exhibited better relaxation in empagliflozin-treated animals. Myocardial consumption of glucose and ketone bodies negatively and positively correlated with diastolic function, respectively.

CONCLUSIONS

Empagliflozin ameliorates diastolic function in a nondiabetic HF porcine model, mitigates histological and molecular remodeling, and reduces both left ventricle and cardiomyocyte stiffness.

Early ischemia identification employing 2D speckle tracking selective layers analysis during dobutamine stress echocardiography

PURPOSE

Two-dimensional (2D) strain derived from speckle tracking proved to be feasible and accurate in the quantitative evaluation of myocardial ischemia during stress echocardiography. We compared the accuracy in detecting myocardial ischemia of the transmural segmental analysis with an endocardial specific evaluation in 20 patients undergoing dobutamine stress echocardiography (DSE) and coronary angiography.

METHODS

Peak systolic global strain (G-ε) and at the subendocardial level (Endo-ε) were measured off-line at rest, a low dose, and peak stress; then, we compared the results with wall-motion analysis and significant coronary artery disease (CAD > 70% diameter stenosis). Endocardial strain variation from basal to low and peak dose was computed both for global or subendocardial analysis. The utilization of the ROC curve allowed us to derive optimal cutoffs, sensibility and specificity for ischemic segments.

RESULTS

The subendocardial analysis at high dose showed to be able to increase significantly the accuracy of the test to detect the ischemic segments (sens 90.2% vs 85.4%; spec 93.1% vs 92.2%). Moreover, at the low dose, the subendocardial analysis showed to be able to increase significantly, mostly the specificity of the test (sens 69.6% vs 68.3%; spec 92.2% vs 86.2%). Notably, the strain subendocardial analysis at low dose showed to reach a high specificity, similar to the peak dose transmural analysis.

CONCLUSIONS

Measurement of subendocardial strain during DSE is feasible and can increase the accuracy of the test. Moreover, the subendocardial strain during DSE can reach a high specificity, even limiting the test at a low dose infusion.

A speckle-tracking strain-based artificial neural network model to differentiate cardiomyopathy type

Objectives. In heart failure, invasive angiography is often employed to differentiate ischaemic from non-ischaemic cardiomyopathy. We aim to examine the predictive value of echocardiographic strain features alone and in combination with other features to differentiate ischaemic from non-ischaemic cardiomyopathy, using artificial neural network (ANN) and logistic regression modelling. Design. We retrospectively identified 204 consecutive patients with an ejection fraction <50% and a diagnostic angiogram. Patients were categorized as either ischaemic (n = 146) or non-ischaemic cardiomyopathy (n = 58). For each patient, left ventricular strain parameters were obtained. Additionally, regional wall motion abnormality, 13 electrocardiographic (ECG) features and six demographic features were retrieved for analysis. The entire cohort was randomly divided into a derivation and a validation cohort. Using the parameters retrieved, logistic regression and ANN models were developed in the derivation cohort to differentiate ischaemic from non-ischaemic cardiomyopathy, the models were then tested in the validation cohort. Results. A final strain-based ANN model, full feature ANN model and full feature logistic regression model were developed and validated, F₁ scores were 0.82, 0.79 and 0.63, respectively. Conclusions. Both ANN models were more accurate at predicting cardiomyopathy type than the logistic regression model. The strain-based ANN model should be validated in other cohorts. This model or similar models could be used to aid the diagnosis of underlying heart failure aetiology in the form of the online calculator (https://cimti.usj.edu.lb/strain/index.html) or built into echocardiogram software.

Untargeted metabolomic analysis of coronary artery disease patients with diastolic dysfunction show disturbed oxidative pathway

INTRODUCTION

Left ventricular diastolic dysfunction (LVDD) is common in patients with coronary artery disease (CAD) with prevalence estimates of 34% and constitutes a predictor of all-cause mortality. Although diastolic dysfunction is induced by myocardial ischemia and has been shown to alter the clinical course, the role of coronary artery disease in the diastolic dysfunction and its progression into heart failure has not been completely elucidated.

OBJECTIVE

The present study was conducted to identify possible metabolites in coronary artery disease patients that are differentially regulated in patients with diastolic dysfunction.

METHODS

The serum of CAD (n = 75) patients and young healthy volunteers (n = 43) were analysed by using gas chromatography mass spectrometry (GC-MS) technique. Pre-processing of data results in 1547 features; among them 1064 features were annotated using NIST library.

RESULTS AND CONCLUSION

Fifteen metabolites were found to be statistically different between cases and control. Variation in metabolites were identified and correlated with several clinically important echocardiography parameters i.e. LVDD grades, ejection fraction (EF) and E/e' values. The results suggested that metabolic products of fatty acid oxidation and glucose oxidation pathways such as oleic acid, stearic acid, palmitic acid, linoleic acid, galactose, pyruvic and lactic acids are predominantly up regulated in patients with coronary artery disease and severity of diastolic dysfunction appears to be linked to increase in fatty acid oxidation and inflammation. The metabolic fingerprints of these patients give us an insight into the pathophysiological mechanism of diastolic dysfunction in coronary artery disease patients although it did not identify validated novel markers.

Relation of blood pressure variability to left ventricular function and arterial stiffness in hypertensive patients

INTRODUCTION

Variability of blood pressure (BP) has been reported to be related to worse cardiovascular outcomes. We examined the impact of daytime systolic BP variability on left ventricular (LV) function and arterial stiffness in hypertensive patients.

METHODS

Ambulatory BP monitoring (ABPM) and echocardiography were performed in 116 hypertensive patients. We assessed BP variability as standard deviations of daytime systolic BP on 24-hour ABPM. Conventional echocardiographic parameters, area strain and three-dimensional diastolic index (3D-DI) using 3D speckle tracking were measured. Arterial stiffness was evaluated by acquiring pulse wave velocity (PWV) and augmentation index.

RESULTS

Patients with higher BP variability showed significantly increased left ventricular mass index (LVMI) and late mitral inflow velocity, as well as decreased E/A (early mitral inflow velocity/late mitral inflow velocity) ratio, area strain and 3D-DI than those with lower BP variability (LVMI: p = 0.02; A velocity: p < 0.001; E/A ratio: p < 0.001; area strain: p = 0.02; 3D-DI: p = 0.04). In addition, increased BP variability was associated with higher PWV and augmentation index (p < 0.001). Even among patients whose BP was well controlled, BP variability was related to LV mass, diastolic dysfunction and arterial stiffness.

CONCLUSION

Increased BP variability was associated with LV mass and dysfunction, as well as arterial stiffness, suggesting that BP variability may be an important determinant of target organ damage in hypertensive patients.

Challenges for 'diastology': contributions from Japanese researchers

Diastology is a study to treat diastole of the heart. Transmitral flow and pulmonary venous flow velocities recorded by pulsed Doppler echocardiography provide more important information about left ventricular (LV) diastolic dysfunction [left atrial (LA)-LV coupling] than cardiac catheterization in clinical practice; however, these waveforms are influenced by loading conditions, particularly preload. The early diastolic mitral annular and LV wall motion indices measured by tissue Doppler echocardiography can evaluate LV relaxation abnormality and filling pressure by being relatively preload independent. In addition, the role of concomitant systolic longitudinal dysfunction is well characterized in asymptomatic patients and in patients with heart failure and preserved ejection fraction. Two-dimensional speckle tracking echocardiography is an angle-independent method, and has the potential to evaluate the contraction and relaxation abnormalities in the longitudinal, circumferential, and radial directions of the LV myocardium as well as LV torsion/untwisting and, moreover, deformation of the LA myocardium and large arterial wall. As a result, this new technique can facilitate the early detection of impaired LA-LV-arterial coupling in patients before occurrence of overt heart failure symptoms.

Correlation Between Diastolic Dysfunction and Coronary Artery Disease on Coronary Computed Tomography Angiography

Aims:

We investigated the relationship between coronary artery calcium score (CACS) and coronary artery disease (CAD) on coronary computed tomography angiography (CCTA), and measures of left ventricular diastolic function (DD).

Methods:

We included 429 consecutive patients (39% women; mean age 49 ± 12 years) without known CAD, who underwent CCTA and transthoracic echocardiography (TTE) within 1-month. Evaluation of CCTA was per vessel, and per segment basis for intraluminal diameter stenosis. We also used the 16-segment model to determine overall coronary plaque burden with segment involvement score (SIS). DD on TTE was assessed using mitral inflow E wave-to-A wave ratio (EAR) and tissue Doppler early mitral annual tissue velocity axial excursion.

Results:

A total of 293 (68.4%) patients had DD, 15.4% had more than stage 2 DD. The presence of DD was associated with increasing CACS (P < 0.001). Similarly, there was a statistically significant correlation between EAR and CCS (r = −0.147, P = 0.004) and SIS (r = 0.536, P < 0.001). The prevalence of more than stage 2 DD was associated with higher prevalence of obstructive CAD (26.2% vs. 11.7%, P < 0.0001). In multivariable analyses, the independent predictors of more than stage 1 DD are the age (P < 0.001), and diabetes (P = 0.010), while the CACS and SIS were not independently associated with DD.

Conclusion:

Our analysis suggests that CACS, as well as CAD by CCTA, are not independently associated with measures of DD on echocardiography.

Important advances in technology: echocardiography

Echocardiography has evolved over the past 45 years from a simple M-mode tracing to an array of technologies that include two-dimensional imaging, pulsed and continuous wave spectral Doppler, color flow and tissue Doppler, and transesophageal echocardiography. Together, these modalities provide a comprehensive anatomic and functional evaluation of cardiac chambers and valves, pericardium, and ascending and descending aorta. The switch from analog to digital signal processing revolutionized the field of ultrasound, resulting in improved image resolution, smaller instrumentation that allows bedside evaluation and diagnosis of patients, and digital image storage for more accurate quantification and comparison with previous studies. It also opened the door for new advances such as harmonic imaging, automated border detection and quantification, 3-dimensional imaging, and speckle tracking. This article offers an overview of some newer developments in echocardiography and their promising applications.

Stress-echocardiography is underused in clinical practice: a nationwide survey in Austria

BACKGROUND

The wide area of application, including coronary artery disease, valvular heart disease, or pulmonary hypertension makes stress echocardiography (SE) a powerful, cost-effective imaging modality in cardiology. The role of this technique in clinical practice in Austria is unknown.

METHODS

A nationwide survey included all departments for cardiology and/or internal medicine in the years 2008 and 2013. By electronic questionnaire demographics, indication for the test, the numbers of examined cases per year, operators, and various applied techniques of SE were interrogated and completed by telephone interviews.

RESULTS

Data could be obtained from all 117 departments. In the year 2007 in 58 (50%) and in 2012 57 (49%) departments SE was available in Austrian hospitals. More than 100 SEs per year were performed by only four (7%) units in the year 2007 and by five (8%) in 2012. Physical exercise, dobutamine, and dipyridamole SE were available in 27 (46%), 52 (90%), and six (10%) units in 2007, and in 15 (27%), 52 (91%), and five (9%) units in 2012, respectively. In 2007 41 (71%) and in 2012 26 (46%) echo-labs administered contrast agents during SE. Transesophageal SE and 3D-echo was performed in one (2%) and three (5%) units in 2007, and in six (10%) and four (7%) echo-labs in 2012.

CONCLUSIONS

This representative survey demonstrates the underuse of SE in clinical practice in Austria. Even in established application fields performance is low, examination frequencies as recommended by the cardiology societies are fulfilled only by a minority of institutions.

The Prognostic Utility of Echo-Estimated Left Ventricular End-Diastolic Pressure-Volume Relationship in Stable Coronary Artery Disease: The Heart and Soul Study

BACKGROUND

While changes in the left ventricular end-diastolic pressure-volume relationship (LV-EDPVR) can be estimated using echocardiography, their prognostic utility in stable coronary artery disease (CAD) is unknown.

METHODS

Using echo-estimated LV end-diastolic volume index and diastolic function category, the relative position of the LV-EDPVR was defined in 901 participants with stable CAD as: (1) left-shifted, (2) right-shifted, or (3) intermediate. We then evaluated the association of LV-EDPVR position relative to the intermediate category with time to hospitalization for heart failure (HF) or cardiovascular (CV) death using Cox proportional hazards models.

RESULTS

During 7.0 ± 3.1 years of follow-up, there were 207 admissions for HF or CV deaths. Both leftward and rightward shifts of LV-EDPVR were associated with a significantly higher risk of HF or CV death (HR 1.73, 95% CI 1.15-2.62 and HR 6.75, 95% CI 4.02-11.31, respectively). In multivariable-adjusted models, these associations were attenuated but remained significant (HR 1.66, 95% CI 1.08-2.55 for left-shifted and HR 4.19, 95% CI 2.32-7.55 for right-shifted). The association of LV-EDPVR with HF or CV death was no longer significant after inclusion of N-terminal pro-brain natriuretic peptide level as a covariate.

CONCLUSIONS

In stable CAD, echo-estimated leftward and rightward shifts in the LV-EDPVR are associated with HF and CV death. The loss of these associations after adjustment for N-terminal pro-brain natriuretic peptide level suggests that echo-estimated LV-EDPVR captures changes in LV filling pressure at any given LV end-diastolic volume.

The value of assessing myocardial deformation at recovery after dobutamine stress echocardiography

Background

The purpose of this study was to evaluate whether performing an assessment of myocardial deformation using speckle tracking imaging during the recovery period after dobutamine stress echocardiography (DSE) allows detection of significant coronary artery disease (CAD) in patients with chest discomfort.

Methods

DSE and coronary angiography were performed in 44 patients with chest discomfort. The mean global longitudinal peak systolic strain (GLS) was measured at rest, at low stress (dobutamine infusion rate of 10 µg/kg/min) and at recovery (5 min after cessation of dobutamine infusion) of DSE using automated function imaging with apical views. Fractional flow reserve (FFR) was also performed in patients with intermediate coronary stenosis. CAD was defined as having a ≥ 70% diameter stenosis on coronary angiography or as having a FFR < 0.8. Patients were divided two groups based on the absence or presence of CAD [CAD (-) group vs. CAD (+) group].

Results

There were no significant differences in the clinical characteristics and results of conventional echocardiography between the two groups. GLS at recovery was lower in the CAD (+) group than in the CAD (-) group (-18.0 ± 3.4% vs. -21.0 ± 1.9%, p = 0.003). The optimal cutoff of GLS at recovery for detection of CAD was -19% (sensitivity of 70.6%, specificity of 83.3%).

Conclusion

Assessment of GLS at recovery of DSE is a reliable and objective method for detection of CAD. This finding may suggest that systolic myocardial stunning remains even after recovery of wall motion abnormalities in patients with CAD.

Utility of global strain by two-dimensional and three-dimensional speckle tracking for assessing left ventricular diastolic function: comparison with pressure wire analysis

Background and Objectives

We evaluated the utility of two-dimensional (2D) and three-dimensional (3D) left ventricular (LV) global myocardial deformity parameters for assessing LV diastolic function by comparing invasive measures of LV performance.

Subjects and Methods

Echocardiography and LV pressure were assessed in 39 patients. Myocardial LV longitudinal, circumferential, and radial deformations, as well as area strain, were evaluated utilizing 2D and 3D speckle tracking software. The 2D early diastolic strain rate (2D-SRe) was measured from the 3 apical and 3 short axis views. The 3D diastolic index (3D-DI) was calculated by the % change of global strain during the first one-third of the diastolic period. LV end diastolic pressure (LVEDP) and the rate of LV pressure change (dP/dt) were collected using a pressure-conducted catheter and tau was calculated.

Results

dP/dt_min were related to early mitral annular velocity (e'), 2D-SRe_long, 2D-SRe_radial, as well as 3D-DI_long, and 3D-DI_as. Additionally, LVEDP was associated with the ratio of mitral early diastolic velocity (E) to 2D-SRe_long, 2D-SRe_circ, 2D-SRe_radial, 3D-DI_long, 3D-DI_circ, and 3D-DI_as. E/2D-SRe_long, E/2D-SRe_radial, E/3D-DI_long, and E/3D-DI_as were comparable with E/e' in predicting patients with elevated LVEDP. Among those patients with E/e' of 8 to 15, E/3D-DI_long provided incremental value in identifying those with LVEDP ≥15 mm Hg.

Conclusion

2D-SRe_long, 2D-SRe_radial, 3D-DI_long, and 3D-DI_as were related to LV relaxation, and the ratios of E to those parameters were associated with LVEDP. In addition, among patients with indeterminate E/e', E/3D-DI_long offered incremental value in predicting elevated LVEDP, suggesting it may provide supplementary information in the evaluation of LV diastolic function.

Risk stratification of patients with non-ST-elevation acute coronary syndromes by assessing global longitudinal strain

Noninvasive detection of left main/three-vessel diseases (LM/3VD) among patients with non-ST-elevation acute coronary syndromes (NSTEACS) has been difficult using echocardiography. However, two-dimensional (2D) strain/strain-rate analysis is more sensitive in quantitatively assessing contractile abnormality. Accordingly, we aimed to clarify the usefulness of 2D strain/strain-rate analysis for risk stratification of NSTEACS. A total of 50 patients with NSTEACS underwent echocardiography and coronary angiography. We evaluated global longitudinal peak strain (global PS), peak systolic strain rate (global SSR), early diastolic global peak strain rate (global ESR), time from aortic valve closure to peak strain (TAVC-global PS), and global ESR (TAVC-global ESR) in apical four-, two-, and three-chamber views. Patients were divided into two groups according to coronary angiographic findings, the high-risk group (n = 15) with either of left main or three-vessel disease, and the low-risk group (n = 35). There were no significant differences in global SSR and global ESR between the two groups. The amplitude of global PS was significantly reduced in high-risk patients with LM/3VD in comparison with low-risk patients (-17.5 ± 2.4% vs -19.8 ± 2.7%, P = 0.007, respectively). TAVC-global PS and TAVC-global ESR were significantly prolonged in high-risk patients with LM/3VD in comparison with low-risk patients (15.3 ± 25.7 ms vs -36.8 ± 32.7 ms, P < 0.0001 and 162.8 ± 32.7 ms vs 135.7 ± 41.5 ms, P < 0.03, respectively). Receiver-operating characteristic analysis demonstrated that TAVC-global PS most strongly detected high-risk patients with sensitivity of 100% and specificity of 74.3% (area under the curve = 0.938, 95 % confidence interval 0.832-0.986, P = 0.0001). Temporal analysis of 2D strain appeared to be useful in detecting high-risk patients with LM/3VD among patients with NSTEACS.

Evaluation of the anti-myocardial ischemia effect of individual and combined extracts of Panax notoginseng and Carthamus tinctorius in rats

ETHNOPHARMACOLOGICAL RELEVANCE

The decoction of combined Panax notoginseng (Burk) F.H. Chen and Carthamus tinctorius L. has a history of use in traditional medicine for the prevention and treatment of cardiovascular diseases such as angina pectoris and myocardial infarction.

AIM OF THE STUDY

In this study, we investigated the effects of individual herbal extracts and combined extracts on anti-myocardial ischemia injuries in vivo, and determined the proper dosage of Panax notoginseng (EPN) combined with Carthamus tinctorius (ECT) that could strengthen their cardio-protective effects. Meanwhile, their potential anti-oxidative stress and anti-inflammation effect were assessed.

MATERIAL AND METHODS

SD rats were orally given individual EPN 50, 100mg/kg, ECT 100, 200mg/kg, and different combinations between them. Myocardial infarction was produced by occlusion of the left anterior descending coronary artery for 24h. Infarct area was determined with 2,3,5-triphenyltetrazolium chloride (TTC) staining. The biomarkers related to myocardial ischemia injury were determined. Simultaneously, hemodynamic parameters were monitored as left ventricular systolic pressure (LVSP), LV end-diastolic pressure (LVEDP) and maximal rate of increase and decrease of left ventricular pressure (dP/dt(max)). The oxidative stress indicators and inflammatory factors were also evaluated.

RESULTS

The results showed EPN or ECT significantly reduced infarct size, improved cardiac function, decreased levels of creatine kinase (CK) and lactate dehydrogenase (LDH) (all P<0.05 vs. control ). EPN or ECT alone also restrained the oxidative stress related to myocardial ischemia injury as evidenced by decreased malondialdehyde (MDA) and elevated superoxide dismutase (SOD) activity (all P<0.05 vs. control). However, this cardio-protective effect was further strengthened by their combinations. Among all the combinations, EPN 50mg/kg plus ECT 200mg/kg showed predominant potential to reduce infarct size (22.21±1.72%, P<0.05 vs. each single, respectively), preserve cardiac function (P<0.05 vs. ECT 200mg/kg for LVEDP and -dP/dt(max)) after myocardial ischemia injury in rats. This heart protection was confirmed with the lowered cardiac troponin I (cTnI) (P<0.05 vs. ECT 200mg/kg and EPN 50mg/kg, respectively). Oxidative stress and inflammation are the two key factors in the pathogenesis of myocardial ischemia injury. In the present study, EPN 50mg/kg plus ECT 200mg/kg markedly increased SOD and GSH-Px activity (475.30±23.60U/ml, P<0.05 vs. each single, respectively), while elevated MDA level was significantly depressed. Meanwhile, the inflammatory cascade was inhibited as evidenced by decreased cytokines such as tumor necrosis factor-α (TNF-α), C-reactive protein (CRP) and interleukin-1β (IL-1β).

CONCLUSION

These results demonstrated EPN, ECT and their combinations exhibited significant cardio-protective effects. The findings suggest EPN combined with ECT may be therapeutically more useful for ameliorating anti-myocardial ischemia injuries than individual herbal extract, and EPN 50mg/kg plus ECT 200mg/kg is the appropriate combination in the present research. The cardio-protective effect of this combination was achieved partially by decreasing oxidative stress and repressing inflammatory cascade.

Four-dimensional speckle tracking for assessing improvement in left ventricular contractility after coronary angioplasty

The objective of the study was to identify and quantify the potential improvement of left ventricular contractility after percutaneous transluminal coronary angioplasty (PTCA) using 4-dimensional (4D) speckle tracking echocardiography (4D STE). We investigated 41 patients with coronary disease by 4D STE pre- and 24 hours postcoronarography with (n = 18) or without (n = 23) PTCA. The 4D STE visualizes in real time the myocardium strain on 2- and 4-chamber apical views and on 3 transverse views of the left ventricle. Average and total strain of the left ventricle were measured. Of the 18 PTCA patients, 15 showed significant increase in left ventricle mean (+15 ± 6) and total strain (240 ± 100), which corresponded to an increase of 93% ± 55% from precoronarography, whereas the remainder showed no change. The total strain corresponded to 33% ± 10% (before PTCA) and 59% ± 11% (post PTCA) of the estimated normal strain for each patient. Strain improved in 70% of the segment downstream from the stent, and there was a negative correlation between the amplitude of the mean and total strain improvements after 24 hours and the mean and total strain values before PTCA. In the non-PTCA group, 21 of the 23 patients showed no changes in strain, whereas 2 showed improvement. The 4D STE showed significant improvements in left ventricular contractility in more than 70% of the areas downstream from the PTCA segment. This corresponded to an increase in the initial contractility by approximately 93% ± 55%; however, the myocardium contractility remained approximately 59% of normal level. No changes were seen in patients without PTCA.

A novel global strain diastolic index correlates with plasma NT-proBNP levels in asymptomatic hypertensive patients with preserved left ventricular ejection fraction

BACKGROUND

The strain imaging diastolic index (SI-DI) was reported to be a sensitive marker of regional left ventricular (LV) delayed relaxation induced by ischemia. However, the clinical usefulness of the global SI-DI has not been evaluated. N-terminal pro-brain natriuretic peptide (NT-proBNP) is a sensitive biomarker for the detection of asymptomatic diastolic LV dysfunction. This study investigated the ability of a novel parameter, the global SI-DI, obtained using 2D speckle tracking imaging (2DSI) to correlate with the plasma NT-proBNP levels in asymptomatic hypertensive patients with preserved LV ejection fraction.

METHODS

We performed 2D echocardiography and 2DSI in 83 asymptomatic hypertensive patients with preserved ejection fraction (>45 %) and in 37 control subjects. In 2DSI, the LV longitudinal peak strain and the SI-DI of 18 LV segments were measured. NT-proBNP was measured in all subjects. The data were compared between hypertensive patients and normal controls.

RESULTS

The average peak strain and global SI-DI of 18 LV segments were significantly reduced in hypertensive patients compared with control subjects (P < 0.05); however, only the global SI-DI was significantly correlated with log10 NT-proBNP (r = -0.469, P = 0.001). In Pearson's correlation analyses, log10 NT-proBNP was significantly correlated with E/e', E/A ratio, early diastolic mitral annular velocity (e'), global peak strain, deceleration time of the E-wave, and LV ejection fraction. In the multiple stepwise regression analysis, the global SI-DI was the strongest independent determinant of log10 NT-proBNP (β = -0.386, P = 0.008).

CONCLUSIONS

The global SI-DI derived from 2DSI correlates well with plasma NT-proBNP levels and may have prognostic value in asymptomatic hypertensive patients with preserved ejection fraction.

Effect of embolic particles during coronary interventional procedures on regional wall motion in patients with stable angina pectoris

Microembolization during percutaneous coronary intervention (PCI) causes minor myocardial injury, and a Doppler guidewire can detect embolic particles as high-intensity transient signals (HITS). The present study investigated the effect of microembolization during PCI on regional wall motion using a Doppler guidewire and myocardial strain analysis. We performed PCI to the left anterior descending coronary artery in 25 patients (18 men and 7 women, 68 ± 8 years old) with stable angina pectoris. Coronary flow spectrums were obtained with a Doppler guidewire to count the total number of HITS throughout the PCI procedures. On the days before and after PCI, we recorded echocardiography and measured the longitudinal peak systolic strain, peak strain rate, and early diastolic strain rate in the left anterior descending territory using a 2-dimensional speckle tracking method. PCI was successfully performed, and 10 ± 6 HITS (range 0 to 22, median 9) were recognized during PCI. The echocardiographic study showed no visible wall motion abnormalities in the left anterior descending territory either after or before PCI. In cases in which the total number of HITS was ≥10, the peak systolic strain, peak strain rate, and early diastolic strain rate worsened on the day after PCI compared with those on the day before PCI (p <0.01). The rates of change in peak systolic strain and early diastolic strain rate, defined as the ratios of those parameters after PCI to those before PCI, had modest to strong inverse correlations with the total number of HITS (R(2) = 0.35 and R(2) = 0.46, respectively). In conclusion, periprocedural microembolization during PCI reduces subclinical cardiac function in patients with stable angina pectoris.

Persistence of systolic and diastolic regional dysfunction after brief episodes of myocardial ischemia evaluated with velocity vector imaging

BACKGROUND

The time course and characteristics of persistent regional dysfunction after ischemia remain unclear. Velocity vector imaging (VVI) allows accurate quantification of regional myocardial function. The aim of this study was to characterize the time course of regional diastolic and systolic abnormality after recovery from different durations of ischemia by VVI.

METHODS

72 rats underwent brief left coronary occlusion (3, 5, 10 and 15 min, respectively) followed by reperfusion for 4-8h. Hemodynamic measurements and VVI were performed at various time points. Regional systolic and diastolic functions were estimated from peak diastolic and systolic circumferential strain rate (SR-d and SR-s) of the left ventricle, respectively.

RESULTS

Both SR-d and SR-s were significantly decreased in the ischemic segment during occlusion compared to non-ischemic segment. With the increase in occlusive time, the duration of reduced SR-d and SR-s after reperfusion was prolonged. Both SR-d and SR-s returned to pre-occlusion values in less than 30 min after reperfusion in the 3 min and 5 min ischemia groups. However, in the 10- and 15-min ischemia groups, SR-d did not fully recovered even at 240 min after reperfusion despite complete recovery of SR-s. The left ventricular hemodynamics during occlusion were significantly changed in all groups and returned to baseline immediately after reperfusion.

CONCLUSION

The persistence of diastolic regional dysfunction is longer than systolic regional dysfunction after a relative longer ischemic event, suggesting that recent myocardial ischemic insult mimicking variant angina may be recognized with the evaluation of regional diastolic function.

Early detection of isolated left ventricular diastolic dysfunction in high-risk differentiated thyroid carcinoma patients on TSH-suppressive therapy

OBJECTIVE

L-Thyroxine-suppressive therapy benefits high-risk differentiated thyroid cancer patients by decreasing recurrence rates and cancer-related mortality. However, fully suppressed serum thyroid-stimulating hormone (TSH) implies a state of subclinical hyperthyroidism (SCH) with associated adverse cardiac effects. Because left ventricular (LV) diastolic dysfunction may be the first manifestation of more severe LV failure, and to balance the risks from thyroid cancer recurrence with risks of cardiac failure, the purpose of this study was to analyse new parameters of LV function in asymptomatic patients with exogenous SCH.

DESIGN

Case-control study with 24 patients on TSH-suppressive therapy of short duration (≤ 4 years) after thyroid ablative therapy for differentiated thyroid carcinoma and 20 age- and sex-matched subjects.

MEASUREMENTS

LV function [LV global strain and strain rate (SR) curves] was assessed by speckle tracking imaging echocardiography in each subject.

RESULTS

Patients and controls do not differ in body mass index, systolic blood pressure and heart rate. No significant differences were observed in LV morphology (LV mass and relative wall thickness), cardiac output and parameters of LV systolic function between patients on suppressive therapy and controls. When compared with controls, patients with exogenous SCH had a significantly impaired longitudinal protodiastolic strain, SR and strain diastolic index but preserved radial strain and SR function.

CONCLUSIONS

In subjects with SCH at the early phase of TSH-suppressive therapy, evidence of isolated longitudinal LV diastolic dysfunction was observed, despite a normal LV morphology. Further prospective studies to clarify the prognosis of picking-up early diastolic dysfunction in asymptomatic patients are needed before serial measurements could be recommended.