Association of left ventricular global area strain derived from resting 3D speckle-tracking echocardiography and exercise capacity in individuals undergoing treadmill exercise test.

Background: Left ventricular (LV) global area strain (GAS) is a novel index derived from resting 3D speckle-tracking echocardiography (STE), and its clinical significance has rarely been studied. We examined the association of LV GAS and exercise capacity in a health check-up population. Methods: We recruited 94 symptom-free participants (52.2 ± 11.7 years, 62.8% male) without substantial structural heart disease or coronary heart diseases who were undergoing a routine health examination. All participants underwent resting echocardiography and symptom-limited treadmill exercise test according to the Bruce protocol. Four strain parameters were obtained from the analysis, namely 3D GAS (GAS3d), global longitudinal strain, global circumferential strain, and global radial strain. Results: After multivariate analysis for factors of exercise time, we observed a significant association in LV GAS3d (P < 0.001). We divided participants into preserved and impaired exercise capacity groups according to the cutoff value of 8 metabolic equivalent of tasks. LV GAS3d (OR 1.24, 95% CI 1.10-1.39, P < 0.001) was an independent predictor of impaired exercise capacity and the optimal cut-off value was -19.96% at a sensitivity of 77.8% and at a specificity of 92.1%. LV GAS3d could improve the discriminatory power of exercise capacity in individuals with early mitral filling velocity to average mitral annulus velocity ratio (E/e') ≥ 8. Conclusions: LV GAS3d was significantly associated with exercise time and exhibited incremental predictive value on E/e' for exercise capacity in participants undergoing treadmill exercise test.

Automated Recognition of Regional Wall Motion Abnormalities Through Deep Neural Network Interpretation of Transthoracic Echocardiography.

BACKGROUND: Automated interpretation of echocardiography by deep neural networks could support clinical reporting and improve efficiency. Whereas previous studies have evaluated spatial relationships using still frame images, we aimed to train and test a deep neural network for video analysis by combining spatial and temporal information, to automate the recognition of left ventricular regional wall motion abnormalities. METHODS: We collected a series of transthoracic echocardiography examinations performed between July 2017 and April 2018 in 2 tertiary care hospitals. Regional wall abnormalities were defined by experienced physiologists and confirmed by trained cardiologists. First, we developed a 3-dimensional convolutional neural network model for view selection ensuring stringent image quality control. Second, a U-net model segmented images to annotate the location of each left ventricular wall. Third, a final 3-dimensional convolutional neural network model evaluated echocardiographic videos from 4 standard views, before and after segmentation, and calculated a wall motion abnormality confidence level (0-1) for each segment. To evaluate model stability, we performed 5-fold cross-validation and external validation. RESULTS: In a series of 10 638 echocardiograms, our view selection model identified 6454 (61%) examinations with sufficient image quality in all standard views. In this training set, 2740 frames were annotated to develop the segmentation model, which achieved a Dice similarity coefficient of 0.756. External validation was performed in 1756 examinations from an independent hospital. A regional wall motion abnormality was observed in 8.9% and 4.9% in the training and external validation datasets, respectively. The final model recognized regional wall motion abnormalities in the cross-validation and external validation datasets with an area under the receiver operating characteristic curve of 0.912 (95% CI, 0.896-0.928) and 0.891 (95% CI, 0.834-0.948), respectively. In the external validation dataset, the sensitivity was 81.8% (95% CI, 73.8%-88.2%), and specificity was 81.6% (95% CI, 80.4%-82.8%). CONCLUSIONS: In echocardiographic examinations of sufficient image quality, it is feasible for deep neural networks to automate the recognition of regional wall motion abnormalities using temporal and spatial information from moving images. Further investigation is required to optimize model performance and evaluate clinical applications.

Persistent augmentation of central arterial stiffness following viral clearance by direct-acting antivirals in chronic hepatitis C.

Chronic hepatitis C virus (HCV) infection is associated with risk of cardiovascular diseases. Although direct-acting antivirals (DAA) result in rapid eradication of HCV, their long-term impact on arterial stiffness remains unclear. This study aimed to evaluate changes in parameters of central arterial stiffness from pretreatment, through sustained virological response, to one year after viral clearance. Patients with chronic HCV receiving DAA treatment were enrolled prospectively. Medical history and comorbidities of all patients were collected. Lipid profiles, liver stiffness by transient elastography and central blood pressures using pulse wave analysis of the brachial artery by cuff sphygmomanometry were measured before treatment, at viral clearance and at one year following viral clearance. Augmentation index (AIx), a parameter of aortic stiffness, was calculated as the ratio of augmentation pressure to central pulse pressure. After DAA treatment, all included patients with chronic HCV (n = 102) had achieved viral clearance. Cholesterol, low-density lipoprotein (LDL) and triglyceride/high-density lipoprotein (TG/HDL) increased significantly at viral clearance and persisted at one year (all P < .001). AIx was also elevated significantly at viral clearance and persisted one year later (P < .001). Changes in AIx remained significant only in patients with increased values from baseline in either LDL (P < .01) or TG/HDL (P < .001). Central arterial stiffness and lipid profiles in patients with chronic HCV worsen immediately after viral eradication by DAA treatment and persist at one year. Worsening of lipid profiles after DAA treatment contributes to central arterial stiffness in this patient population and persists long term.

Carotid vascular strain predicts cardiovascular events in patients with hypertension.

BACKGROUND: We aim to investigate prognostic effects of carotid strain (CS) and strain rate (CSR) in hypertension. METHODS: We prospectively recruited 120 patients being treated for hypertension (65.8 ± 11.8 years, 58% male) in this observational study. Peak circumferential CS and peak CSR after ejection were identified using two-dimensional speckle tracking ultrasound. Major cardiovascular events were any admission for stroke, acute coronary syndrome, and heart failure. RESULTS: After a mean follow-up period of 63.6 ± 14.5 months, 14 (12%) patients had cardiovascular events. Age (75.3 ± 9.2 vs 64.6 ± 11.6 years; p = 0.001), systolic blood pressure (131.8 ± 15.5 vs 143.1 ± 16.6 mm Hg; p = 0.021), diastolic blood pressure (74.6 ±11.4 vs 82.1 ± 12.2 mm Hg; p = 0.039), use of diuretics (71 vs 92%; p = 0.014), carotid CS (2.17 ± 1.02 vs 3.28 ± 1.14 %; p = 0.001), and CSR (.28 ± .17 vs .51 ± .18 1/s; p < 0.001) were significantly different between the patients who did and did not reach the end-points. Multivariate Cox regression analysis controlling for age, systolic blood pressure, diastolic blood pressure, and use of diuretics showed that CS (HR .425, 95%CI .223-.811, p = 0.009) and CSR (HR .001, 95%CI .000-.072, p = 0.001) were independent predictors for cardiovascular events. CONCLUSION: In conclusions, decreased CS and CSR were associated with cardiovascular events in hypertension.

Atrial deformation correlated with functional capacity in mitral stenosis patients.

BACKGROUND: Left atrial (LA) dysfunction, expressed as impaired LA deformation using two-dimensional (2D) strain imaging, has been observed in association with rheumatic mitral stenosis (MS). However, the clinical role of speckle tracking echocardiography (STE)-derived LA strain has rarely been studied in MS. AIM: This study aimed to identify the determinants of New York Heart Association (NYHA) functional class in patients with mitral stenosis and to investigate the relationship between left atrial deformation as measured by two-dimensional STE-derived LA strain and heart failure symptoms. METHODS: Sixty-nine consecutive patients (20 males and 49 females; mean age: 61 ± 14 years) with rheumatic MS were evaluated using comprehensive 2D and color Doppler echocardiography including STE-derived LA strain (LAS) and peak positive filling strain rate (LASRr) during the LA reservoir phase. Those results were then correlated with NYHA functional class. RESULTS: There were 15 (22%) patients in functional class I, 42 (61%) in functional class II, and 12 (17%) in functional class III. There were no significant differences in mitral valve area, pressure gradient, pulmonary artery pressure, LA emptying fraction, or left ventricular ejection fraction between functional classes. Upon multivariate analysis (controlling for diuretics usage), LAS (ß = -0.233, P = .045) and LASRr (ß = -0.277, P = .014) were independent factors in determining NYHA functional class. CONCLUSIONS: In stable patients with MS, NYHA functional class independently correlated with LAS and LASRr. Left atrial (LA) deformation correlated with heart failure symptoms in patients with MS.

Role of Left Atrial Reservoir Strain Rate in Left Atrial Remodeling in Severe Mitral Regurgitation.

BACKGROUND: Impaired left atrial (LA) reservoir deformation has been found to be associated with poor functional capacity and outcomes in severe chronic mitral regurgitation (MR). Among patients with primary MR (valve incompetence due to mitral valve pathology), we focus on Carpentier II classification (prolapse or flail mitral valve) and aim to investigate determinants for decreased LA reservoir deformation and its impact on LA remodeling in severe MR. METHODS: Among 159 consecutive patients with severe chronic Carpentier II MR (left ventricular ejection fraction ≥ 60%), 55 underwent follow-up echocardiography, which was compared with their baseline study. We used the change of LA volume index as the rapidity of LA remodeling, LA eccentricity index as LA sphericity, and peak LA reservoir strain as well as reservoir strain rate (LASRR) derived from two-dimensional speckle-tracking echocardiography as LA reservoir function. RESULTS: Older age, elongated left atrium, increased LA volume index, as well as reduced left ventricular global longitudinal strain and LA ejection fraction all linked to a poor baseline LASRR (all p < 0.001). A second echocardiography during a mean follow-up of 15.3 ± 8.3 months revealed an enlarged left atrium (increased interval change of LA volume index; p < 0.001). In multivariate analysis, only the difference between the baseline and follow-up LASRR values (Δ: LASRR; odds ratio (OR) 0.037, 95% confidence interval (CI) 0.003-0.496, p = 0.013) predicted accelerated LA remodeling. A poor baseline LASRR was significantly associated with its profound deterioration during the follow-up period (ß: = -0.424, p = 0.002). CONCLUSION: In severe chronic Carpentier II MR, a reduced follow-up LASRR predicted future accelerated LA remodeling. Patients with a poor baseline LASRR are at a higher risk of its deterioration.

Analysis of the Clinical Characteristics, Management, and Causes of Death in Patients with ST-Segment Elevation Myocardial Infarction Treated With Primary Percutaneous Coronary Intervention from 2005 to 2014.

It is unknown whether there has been any change in the causes of death for acute ST-segment elevation myocardial infarction (STEMI) in the era of aggressive reperfusion. We analyzed the direct causes of in-hospital death in patients with STEMI treated with primary percutaneous coronary intervention (PCI) in a tertiary referral center over the past 10 years.We retrospectively analyzed 878 STEMI patients treated with primary PCI in our hospital between January 2005 and December 2014. There were no significant changes in the age and sex of patients, but the prevalence of hypertension and smoking decreased. STEMI severity increased with more patients in Killip classification > 2. The number of out-ofhospital cardiac arrest events also increased over the 10 years. Symptom onset-to-door time did not change in the 10year study period. The care quality was improved with shorter door-to-balloon time for primary PCI and increased use of dual antiplatelet therapy. The all-cause in-hospital mortality was 9.1%, which did not vary over the 10 years. Multivariable analysis showed that Killip classification > 2 was the most important determinant of death. Cardiogenic shock was the major cause of cardiovascular death. There was an increase in non-cardiovascular causes of death in the most recent 3 years, with infection being a major problem.Despite improvement in care quality for STEMI, the in-hospital mortality did not decrease in this tertiary referral center over these 10 years due to increased disease severity and non-cardiovascular causes of death.

Compliance Index, a Marker of Peripheral Arterial Stiffness, may Predict Renal Function Decline in Patients with Chronic Kidney Disease.

BACKGROUND: Compliance index derived from digital volume pulse (CI-DVP), measuring the relationship between volume and pressure changes in fingertip, is a surrogate marker of peripheral arterial stiffness. This study investigated if CI-DVP can predict renal function deterioration, cardiovascular events and mortality in patients with chronic kidney disease (CKD). METHODS: In this prospective observational study, 149 CKD patients were included for final analysis. CI-DVP and brachial-ankle pulse wave velocity (baPWV) were measured, decline in renal function was assessed by the estimated glomerular filtration rate (eGFR) slope. Composite renal and cardiovascular outcomes were evaluated, including ≥50% eGFR decline, start of renal replacement therapy, and major adverse events. RESULTS: Patients in CKD stages 3b to 5 had higher baPWV and lower CI-DVP values than those in patients with CKD stages 1 to 3a. Stepwise multivariate linear regression analysis showed that lower CI-DVP (p =0.0001) and greater proteinuria (p =0.0023) were independent determinants of higher eGFR decline rate. Multivariate Cox regression analysis revealed that CI-DVP (HR 0.68, 95% CI 0.46-1.00), baseline eGFR (HR 0.96, 95% CI 0.94-0.98) and serum albumin (HR 0.17, 95% CI 0.07-0.42) were independent predictors for composite renal and cardiovascular outcomes. CONCLUSIONS: Compliance index, CI-DVP, was significantly associated with renal function decline in patients with CKD. A higher CI-DVP may have independent prognostic value in slower renal function decline and better composite renal and cardiovascular outcomes in CKD patients.

The role of echocardiographic study in patients with chronic kidney disease.

Despite the recent enormous advances in medicine, high mortality and morbidity rates among the chronic kidney disease (CKD) patients remain an important but unresolved issue. Cardiovascular disease is a major cause of mortality and morbidity in patients with CKD. Abnormal left ventricular geometry and functions are common in this patient group and have been proven to be correlated with a high cardiovascular mortality/morbidity and all-cause mortality. For this reason, echocardiographic study plays an important role in evaluating cardiac structure and functions as well as in stratifying prognostic risk. We here summarize the reported findings on the usefulness of echocardiographic methodologies and identify their roles in diagnostic and prognostic clinical approaches.

Right Ventricular Pacing-Induced Heart Failure after Mitral Valve Replacement.

UNLABELLED: It is an unfortunate fact that pacing-induced heart failure after cardiac surgery is frequently ignored by medical professionals. A 60-year-old woman with chronic atrial fibrillation with a single-lead right ventricular permanent pacemaker for a prolonged ventricular pause underwent mitral valve replacement 6 months later for severe stenosis (NYHA functional class III). The patient's pacing rate was increased from the preoperative level of 60 beats per minute (bpm) to 70 bpm in order to facilitate weaning from the cardiopulmonary bypass. However, her postoperative low cardiac output continued to progress, despite the presence of inotropes. The patient's cold limbs and oliguria persisted until she underwent echocardiographic imaging, which showed dyssynchronous ventricular contraction 29 days post-surgery but which improved after the pacing rate was reduced below her spontaneous rate. Ultimately, clinicians should exercise caution when increasing right ventricular pacing for postoperative stunned myocardium. Due to the problems that can arise from an increased pacing rate, postoperative pacing strategy in patients complicated with low cardiac output after mitral valve replacement merits further discussion. KEY WORDS: Dyssynchrony; Mitral valve replacement; Right ventricular pacing; Stunned myocardium.

Common quantitative trait locus downstream of RETN gene identified by genome-wide association study is associated with risk of type 2 diabetes mellitus in Han Chinese: a Mendelian randomization effect.

OBJECTIVE: Plasma resistin level is a potential molecular link between obesity and diabetes. Causal role of resistin, type 2 diabetes mellitus (T2DM) and genetic variants have not been thoroughly investigated. Therefore, we conducted a genome-wide association study (GWAS) to identify quantitative trait loci associated with resistin levels and investigated whether these variants were prospectively associated with the development of metabolic syndrome (MetS) and T2DM in an independent community-based cohort, the CardioVascular Disease risk FACtors Two-township Study (CVDFACTS). RESEARCH DESIGN AND METHODS: We genotyped 382 young-onset hypertensive (YOH) subjects with Illumina HumanHap550 chips and searched for quantitative trait loci (QTLs) of resistin in the 1(st) stage GWAS and confirmed the finding in another 559 YOH subjects. Logistic regression was used to examine the Mendelian randomization effects between genotypes of confirmed QTLs and metabolic outcomes in 3400 subjects of CVDFACTS. RESULTS: Two single nucleotide polymorphisms (SNP) (rs3745367 and rs1423096) were significantly associated with resistin levels (p = 5.52 × 10(-15) and p = 2.54 × 10(-20) ) and replicated in another 559 YOH subjects (p = 1.29 × 10(-3) and p = 1.13 × 10(-7) ), respectively. The SNP rs1423096 was further associated with the levels of HDL-C (p = 0.006), the risk of MetS (OR = 2.21, p = 0.0034) and T2DM (OR = 1.62, p = 0.0063) in the CVDFACTS. People with the haplotypes A-G and G-G determined by rs3745367 and rs1423096 showed a significantly increased T2DM risk (p = 0.0068 and p = 0.0035, respectively) compared with those with A-A haplotype. CONCLUSION: We have found that rs3745367 and rs1423096 on the RETN gene were significantly associated with resistin levels. However, rs1423096, downstream of RETN, seems to be associated with MetS and T2DM risk more so than rs3745367. The established genotype-disease association points to a causal association of resistin and T2DM.

Increased aortic stiffness and attenuated lysyl oxidase activity in obesity.

OBJECTIVE: One potential mechanism through which obesity exerts adverse effects on the vascular system is by increasing aortic stiffness, a change known to be predictive of increased cardiovascular mortality. The aim of this study was to investigate the pathophysiology that links obesity to aortic stiffening. APPROACH AND RESULTS: Obese (ob/ob) mice were used to examine physical, morphological, and molecular changes in the aorta in response to obesity. ob/ob mice had increased aortic pulse wave velocity and tissue rigidity. ob/ob aorta exhibited decreases of lysyl oxidase (LOX) activity and cross-linked elastin, and increases of elastin fragmentation and elastolytic activity. The aortas of ob/ob mice were surrounded by a significant amount of proinflammatory and pro-oxidative perivascular adipose tissue. In vitro studies revealed that the conditioned medium from differentiated adipocytes or the perivascular adipose tissue of ob/ob mice attenuated LOX activity. Furthermore, inhibition of LOX in wild-type lean mice caused elastin fragmentation and induced a significant increase in pulse wave velocity. Finally, we found that obese humans had stiffer arteries and lower serum LOX levels than do normal-weight humans. CONCLUSIONS: Our results demonstrated that obesity resulted in aortic stiffening in both humans and mice, and established a causal relationship between LOX downregulation and aortic stiffening in obesity.

2014 Guidelines of Taiwan Society of Cardiology (TSOC) for the Management of Pulmonary Arterial Hypertension.

UNLABELLED: Pulmonary hypertension (PH) is a hemodynamic and pathophysiologic condition, defined as a mean pulmonary arterial pressure exceeding 25 mmHg at rest. According to the recent classifications, it is grouped into pulmonary arterial hypertension (PAH), heart-related, lung-related, thromboembolic, and miscellaneous PH. In the past two decades, tremendous advances have occurred in the field of PH. These include (1) development of clinical diagnostic algorithm and a monitoring strategy dedicated to PAH, (2) defining strong rationales for screening at-risk populations, (3) advent of pulmonary specific drugs which makes PAH manageable, (4) recognition of needs of having proper strategy of combining existing pulmonary specific drugs, and/or potential novel drugs, (5) pursuit of clinical trials with optimal surrogate endpoints and study durations, (6) recognition of critical roles of PH/right ventricular function, as well as interdependence of ventricles in different conditions, especially those with various phenotypes of heart failure, and (7) for rare diseases, putting equal importance on carefully designed observation studies, various registries, etc., besides double blind randomized studies. In addition, ongoing basic and clinical research has led to further understanding of relevant physiology, pathophysiology, epidemiology and genetics of PH/PAH. This guidelines from the working group of Pulmonary Hypertension of the Taiwan Society of Cardiology is to provide updated guidelines based on the most recent international guidelines as well as Taiwan's domestic research on PH. The guidelines are mainly for the management of PAH (Group 1) ; however the majority of content can be helpful for managing other types of PH. KEY WORDS: Pulmonary arterial hypertension; Taiwan guidelines.

Long-term effect of septal or apical pacing on left and right ventricular function after permanent pacemaker implantation.

BACKGROUND: Right ventricular (RV) pacing is associated with left ventricular (LV) dysfunction. However, the effects of RV pacing at different sites on both LV and RV function have rarely been studied before. We want to determine whether different RV pacing sites differentially affect LV and RV deformation by using speckle tracking echocardiography (STE). METHODS: The subjects were 73 patients who had undergone dual-chamber permanent pacemaker implantation and did not have structural heart diseases. LV and RV global longitudinal strains (GLS) were measured using STE to determine subtle changes in LV function. Twenty-three patients without pacing after pacemaker implantation served as controls; 14 and 36 patients showed apical and septal pacing, respectively. RESULTS: There were no significant intergroup demographic differences. LV biplane ejection fractions in the septal- and apical-pacing groups were significantly lower than those in the controls. The GLS LV values were similar between the control and septal-pacing groups, but they were lower in the apical-pacing group. Multivariate analysis revealed that cumulative pacing loads and apical pacing were independent factors associated with lower GLS LV values. The GLS RV values were similar between the control and apical-pacing groups; however, they were lower in the septal-pacing group. CONCLUSION: We concluded that patients with septal pacing have significantly higher GLS LV and more modest decreases in GLS RV values than patients with apical pacing. Thus, septal pacing may be not necessarily preferable in patients without significant heart disease undergoing dual-chamber permanent pacemaker implantation.

Effects of deranged glucose homeostasis on peripheral arterial stiffness index in patients with pre-diabetes mellitus.

Premature arteriosclerosis may be one of the mechanisms linking pre-diabetes mellitus (pre-DM) and cardiovascular disease. We sought to characterize premature arteriosclerosis in pre-DM using different arterial stiffness indices and to find the independent contributors of this process. We recruited 33 patients without DM, 53 patients with pre-DM, and 34 subjects with DM. Both the compliance index (CI) and stiffness index (SI) were measured. Patients with pre-DM and DM had lower CI (3.8 ± 2.1 versus 5.2 ± 3.0 units; P < 0.05 and 3.6 ± 1.8 versus 5.2 ± 3.0 units; P < 0.05, respectively) and higher SI (8.0 ± 2.0 versus 6.7 ± 1.6 m/s; P < 0.01 and 9.4 ± 2.3 versus 6.7 ± 1.6 m/s; P < 0.001, respectively) than patients without DM. Using multivariate linear regression analysis, age, heart rate, and HOMA index were independent determinants for SI (whole model: R(2) = 0.47, P < 0.001), whereas male gender, hsCRP, and HOMA index were independent determinants for CI (whole model: R(2) = 0.34, P < 0.01). The HOMA index was an independent determinant for arterial stiffness. Increased insulin resistance may associate with increased arterial stiffness at peripheral arteries in pre-DM patients.

Significance of strictly defined idiopathic tricuspid regurgitation.

BACKGROUND: Moderate to severe tricuspid regurgitation (TR) is known to cause right ventricular (RV) failure and death. Although TR is traditionally classified as primary or secondary, recently, a new class of TR called idiopathic TR has been proposed, with varying definitions among different studies. METHODS: The data were retrospectively collected for the period of January to June 2018 for 8711 patients from the patient cohort of the National Cheng Kung University Hospital echocardiography laboratory. A total of 670 patients (7.7%) with moderate-to-severe TR were included. Idiopathic TR was diagnosed strictly using a new systematic approach. RESULTS: The distribution of significant TR included 74 (11.0%) primary TR cases, 48 (7.2%) with pacemaker-related TR, 267 (39.9%) with left heart disease, 24 (3.6%) with congenital heart disease, 6 (0.9%) with RV myopathy, 105 (15.7%) with pulmonary hypertension, and 146 (21.8%) with idiopathic TR. The mean age in primary and idiopathic TR groups was older ( p = 0.004), with lower estimated pulmonary pressure ( p < 0.001), higher RV fraction area change (FAC, p < 0.001), and tricuspid annulus systolic velocity (S', p = 0.004) compared with functional TR group. Multivariate analysis showed that idiopathic TR ( p = 0.002) and primary TR ( p = 0.008) had better RV FAC than functional TR. CONCLUSION: Idiopathic TR was associated with better RV function than the other secondary TRs. Thus, idiopathic TR should be strictly defined and regarded as a distinct type of TR.

Effects of postsystolic shortening and diastolic dyssynchrony on myocardial work in untreated early hypertension patients.

OBJECTIVES: Myocardial work is estimated from noninvasive pressure-strain loop for advanced assessment of left ventricular function. Postsystolic shortening and diastolic dyssynchrony of left ventricle were noted early in hypertension. Their novel effects on myocardial work will be illustrated in this study. METHODS: We recruited 43 newly diagnosed hypertensive patients (mean age 51.3 ±â€Š12.5 years, 55.8% men) and 32 age-matched and sex-matched healthy individuals (mean age 52.7 ±â€Š10.5 years, 37.5% men) as control. Pressure-strain loop derived myocardial work incorporated global longitudinal strain from speckle tracking echocardiography with brachial artery cuff pressure. Postsystolic strain index (PSI) was defined by the percentage of postsystolic shortening over peak strain. Diastolic dyssynchrony was assessed by standard deviation of time to peak early diastolic strain rate (TDSr-SD) of 18 segments, and maximal difference of time to peak early diastolic strain rate (TDSr-MD) between any two segments. RESULTS: After multivariate regression analysis, global myocardial work index (GWI) was independently correlated with TDSr-SD (B = -0.498, P = 0.001) and TDSr-MD (B = -0.513, P = 0.001). Global myocardial constructive work (GCW) was independently correlated with TDSr-SD (B = -0.334, P = 0.025) and TDSr-MD (B = -0.397, P = 0.007). Global myocardial wasted work (GWW) was independently correlated with PSI (B = 0.358, P = 0.019). Global myocardial work efficiency (GWE) was lower in hypertensive patients than healthy control (P = 0.001). The untreated hypertensive patients were different from the healthy individuals with higher TDSr-SD, TDSr-MD, GWI, GCW, GWW, and PSI (all P < 0.05). CONCLUSION: In conclusion, the effect of diastolic dyssynchrony mainly influenced constructive work, whereas postsystolic shortening affected wasted work in early untreated hypertension.

Left ventricular systolic strain in chronic kidney disease and hemodialysis patients.

BACKGROUND: The impact of chronic kidney disease (CKD) and hemodialysis on heart function is not fully understood. We aimed to investigate the influence of different stages of CKD and maintenance hemodialysis on heart function. METHODS: One hundred fifty-three patients were categorized into 3 subgroups [56 without CKD as controls; 37 with moderate-advanced CKD, stages 3, 4 or 5, and 60 with end-stage renal disease (ESRD) undergoing maintenance hemodialysis]. Left ventricular (LV) function was assessed by conventional echocardiography and 2-dimensional speckle-tracking echocardiography with strain analysis (2D strain analysis). RESULTS: There was no significant difference of gender, age and LV ejection fraction among groups. Compared with controls, global peak systolic longitudinal strain (GS(l)), circumferential strain and strain rate were decreased in the CKD group. Along with the decline of renal function, GS(l) deteriorated. Moreover, compared with moderate-advanced CKD patients, GS(l), circumferential strain and strain rate were better in ESRD group receiving maintenance hemodialysis. CONCLUSIONS: Worsening renal function was associated with a reduction of systolic function, and could be quantified by 2D strain analysis. The hemodialysis patients have better LV systolic function than the moderate-advanced CKD patients.

Cardiac autonomic functions derived from short-term heart rate variability recordings associated with heart rate recovery after treadmill exercise test in young individuals.

Analysis of short-term heart rate variability (HRV) may provide useful information about autonomic nervous control of heart rate recovery. We studied 495 individuals (273 men), age range 19-85 years, submitted to treadmill exercise tests and short-term HRV evaluations over time (standard deviation of the normal-to-normal interval [SDNN], the square root of the mean squared differences of successive normal-to-normal intervals [RMSSD], the number of interval differences of successive normal-to-normal intervals greater than 50 ms [NN50 count], the proportion derived by dividing NN50 count by the total number of normal-to-normal intervals [pNN50]) and frequency (low-frequency power [LF], high-frequency power [HF], total power) domains. Among 495 patients, 106 patients (68 men) were elderly (age ≥ 65 years). Male gender and hypertension were significantly higher in elderly patients. The young patients had higher HRR after exercise. HRR at 4 min (54 ± 13 vs 60 ± 12 beats/min; P = 0.003) was the most significant predictor for positive exercise test result. In the young group, both time domain measures (SDNN: correlation coefficient 0.34, P < 0.001; RMSSD: correlation coefficient 0.37, P < 0.001) and frequency domain measures (LF: correlation coefficient 0.21, P < 0.001; HF: correlation coefficient 0.13, P = 0.01; total power: correlation coefficient 0.22, P < 0.001) were significantly associated with HRR at 4 min. HRR at 4 min was significantly associated with short-term HRV of time and frequency domains in young individuals, but not elderly ones, receiving treadmill exercise test.