Comparison of two-dimensional speckle and tissue velocity based strain and validation with harmonic phase magnetic resonance imaging

Two-dimensional (2-D) strain (epsilon2-D) on the basis of speckle tracking is a new technique for strain measurement. This study sought to validate epsilon2-D and tissue velocity imaging (TVI)-based strain (epsilonTVI) with tagged harmonic-phase (HARP) magnetic resonance imaging (MRI). Thirty patients (mean age 62 +/- 11 years) with known or suspected ischemic heart disease were evaluated. Wall motion (wall motion score index 1.55 +/- 0.46) was assessed by an expert observer. Three apical images were obtained for longitudinal strain (16 segments) and 3 short-axis images for radial and circumferential strain (18 segments). Radial epsilonTVI was obtained in the posterior wall. HARP MRI was used to measure principal strain, expressed as maximal length change in each direction. Values for epsilon2-D, epsilonTVI, and HARP MRI were comparable for all 3 strain directions and were reduced in dysfunctional segments. The mean difference and correlation between longitudinal epsilon2-D and HARP MRI (2.1 +/- 5.5%, r = 0.51, p <0.001) were similar to those between longitudinal epsilonTVI and HARP MRI (1.1 +/- 6.7%, r = 0.40, p <0.001). The mean difference and correlation were more favorable between radial epsilon2-D and HARP MRI (0.4 +/- 10.2%, r = 0.60, p <0.001) than between radial epsilonTVI and HARP MRI (3.4 +/- 10.5%, r = 0.47, p <0.001). For circumferential strain, the mean difference and correlation between epsilon2-D and HARP MRI were 0.7 +/- 5.4% and r = 0.51 (p <0.001), respectively. In conclusion, the modest correlations of echocardiographic and HARP MRI strain reflect the technical challenges of the 2 techniques. Nonetheless, epsilon2-D provides a reliable tool to quantify regional function, with radial measurements being more accurate and feasible than with TVI. Unlike epsilonTVI, epsilon2-D provides circumferential measurements.     

Comparison of two-dimensional speckle and tissue Doppler strain measurement during dobutamine stress echocardiography: an angiographic correlation.

AIMS: Two-dimensional (2D)-strain derived from speckle-tracking is an alternative to tissue velocity imaging (TVI)-based strain. We compared their feasibility and accuracy in 150 patients undergoing dobutamine stress echocardiography (DSE) and coronary angiography. METHODS AND RESULTS: 2D- and TVI-strain were obtained in three apical views at rest and peak stress. Peak systolic strain rate (SR), endsystolic strain (epsilon(end-sys)), and peak strain (epsilon(peak)) were measured off-line at rest and peak stress, and results were compared with wall motion analysis and significant coronary artery disease (CAD > or = 70% diameter stenosis). Optimal cut-offs were derived from receiver operating characteristic (ROC) curves for sentinel segments. The most feasible method was 2D-strain at rest, and TVI-strain at peak stress. The average peak SR and epsilon(end-sys) at peak stress in segments of patients with significant CAD was less than in segments of patients without CAD (P < 0.0001) and mean PSI at peak stress was higher (P < 0.0001) with both 2D- and TVI-strain. Peak systolic SR at peak stress had the best area under the ROC for both 2D- (AUC 0.67) and TVI-strain (AUC 0.71) for the diagnosis of CAD. The accuracy of WMS (75%) for diagnosis of CAD per patient was similar to 2D-SR (69%) and TVI-SR (74%). The accuracy of 2D-SR and TVI-SR at peak stress was 78 vs. 79% (P = NS) for LAD, 67 vs. 73% (P = NS) for LCX, and 59 vs. 74% (P = 0.008) for RCA disease. CONCLUSION: Measurement of speckle tracking strain during DSE is feasible and similar in accuracy to TVI-strain in the anterior, but not in the posterior circulation.     

Patients with a hypertensive response to exercise have impaired systolic function without diastolic dysfunction or left ventricular hypertrophy

OBJECTIVES: We sought to determine if a hypertensive response to exercise (HRE) is associated with myocardial changes consistent with early hypertensive heart disease. BACKGROUND: An HRE predicts the development of chronic hypertension (HT) and may reflect a preclinical stage of HT. METHODS: Patients with a normal left ventricular (LV) ejection fraction and a negative stress test were recruited into three matched groups: 41 patients (age 56 +/- 10 years) with HRE (>210/105 mm Hg in men; >190/105 in women), comprising 22 patients with (HT+) and 19 without resting hypertension (HT-); and 17 matched control subjects without HRE. Long-axis function was determined by measurement of the strain rate (SR), peak systolic strain, and cyclic variation (CV) of integrated backscatter in three apical views. RESULTS: An HRE was not associated with significant differences in LV mass index. Exercise performance and diastolic function were reduced in HRE(HT+) patients, but similar in HRE(HT-) patients and controls. Systolic dysfunction (peak systolic strain, SR, and CV) was significantly reduced in HRE patients (p < 0.001 for all). These reductions were equally apparent in patients with and without a history of resting HT (p = NS) and were independent of LV mass index and blood pressure (p < 0.01). CONCLUSIONS: An HRE is associated with subtle systolic dysfunction, even in the absence of resting HT. These changes occur before the development of LV hypertrophy or detectable diastolic dysfunction and likely represent early hypertensive heart disease.     

The influence of father absence on the self-esteem and self-reported sexual activity of rural southern adolescents.

The absence of the father in the resident home is an increasing trend in the United States, and the belief that the absence of fathers is lined with a variety of social pathologies is gaining national momentum. This study explored the relationship of father absence on self-esteem and self-reported sexual activity among rural southern adolescents. A sample of 1,409 adolescents (558 males and 851 females) aged 11 to 18 years was surveyed, and the Miller Self-Esteem Questionnaire (MSQ) was used to measure self-esteem. Analysis revealed that increased sexual activity occurred by adolescents in homes where no father present in the residence. Although a statistical significance was noted in the relationship between father absence and lower self-esteem, the magnitude of the difference was not large. Further, no relationship between self-esteem and sexual activity was noted. Seemingly, the absence of the father has a potentially detrimental effect on adolescents' lifestyle choices. Consideration of the notion that the phenomena of fathering rather than the mere presence of a father may contribute to differences in adolescent's lifestyle choices should be studied.     

Patients with type 2 diabetes have exaggerated brachial and central exercise blood pressure: relation to left ventricular relative wall thickness

BACKGROUND: A hypertensive response to exercise has prognostic significance. Patients with type 2 diabetes have vascular abnormalities which may predispose to exaggerated brachial and central blood pressure (BP) during exercise. This study aimed to test this hypothesis and to determine the clinical significance of high exercise BP by examining its relation to left ventricular (LV) mass. METHODS: Brachial and central BP were recorded at rest and in response to maximal exercise in 73 diabetic patients (aged 54 +/- 10 years) and 73 controls (aged 53 +/- 12 years). Brachial BP was recorded using mercury sphygmomanometry and LV mass using 2D-echocardiography. Central BP was estimated by radial tonometry using an exercise-validated generalized transfer function. RESULTS: At rest there were no significant (P > 0.05) differences between groups in brachial or central BP. The diabetic patients had significantly increased exercise brachial systolic BP (SBP: 199 +/- 25 mm Hg vs. 185 +/- 21 mm Hg; P = 0.002) and central SBP (158 +/- 17 mm Hg vs. 149 +/- 15 mm Hg; P = 0.002). There was a significantly higher prevalence of an exaggerated exercise BP response (> or =210/105 mm Hg; men and > or =190/105 mm Hg; women) in the diabetic patients (51% vs. 22%; P < 0.01). Compared with those with normal exercise BP, LV relative wall thickness (RWT) was significantly higher (0.41 +/- 0.09 vs. 0.36 +/- 0.08; P < 0.05) and LV hypertrophy was more prevalent (35% vs. 16%; P < 0.05) in those with a hypertensive response. After accounting for other confounding variables, exercise central SBP remained independently associated with LV RWT (beta = 0.22; P = 0.006). CONCLUSION: Diabetic patients are more likely to exhibit exaggerated exercise BP. Regardless of disease status, high exercise central SBP may contribute to cardiovascular risk via adverse cardiac remodeling.     

Usefulness of at rest and exercise hemodynamics to detect subclinical myocardial disease in type 2 diabetes mellitus

Patients with type 2 diabetes mellitus (T2DM) might have subclinical myocardial dysfunction identified at rest or unmasked during exercise. We examined the correlates of the myocardial exercise response in patients with T2DM. Myocardial dysfunction was sought during at rest and exercise echocardiography in 167 healthy patients with T2DM (97 men, 55 ± 10 years). Myocardial ischemia was excluded using stress echocardiography. Standard echocardiography and color tissue Doppler imaging measures (early diastolic tissue velocity [Em], strain, and strain rate) were acquired at baseline and peak stress. The calibrated integrated backscatter was calculated from the at rest parasternal long-axis view. The longitudinal diastolic functional reserve index after exercise was defined as ΔEm [1 - (1/Em(base))]. The clinical, anthropometric, and metabolic data were collected at rest and stress. Subclinical myocardial dysfunction at baseline (n = 24) was independently associated with weight (odds ratio [OR] 1.02, p = 0.04) and hemoglobin A1c (OR 1.36, p = 0.03). This group displayed an impaired exercise response that was independently associated with a reduced exercise capacity (OR 0.84, p = 0.034) and longitudinal diastolic functional reserve index (OR 0.69, p = 0.001). Inducible myocardial dysfunction (stress Em <-9.9 cm/s) was identified after exercise in 70 of the remaining 143 subjects. This finding was associated with calibrated integrated backscatter (OR 1.08, p = 0.04) and lower peak heart rate (OR 0.97, p = 0.002) but not metabolic control. The intensity of the metabolic derangement in patients with T2DM was associated with subclinical at rest myocardial dysfunction, but not with the myocardial exercise response. In conclusion, the association of an abnormal stress response with nonmetabolic factors, including backscatter and blunted peak heart rate, suggests potential roles for myocardial fibrosis and cardiac autonomic neuropathy in patients with nonischemic diabetic heart disease.     

Myocardial and vascular dysfunction and exercise capacity in the metabolic syndrome

The metabolic syndrome (MS) is associated with cardiovascular risk exceeding that expected from atherosclerotic risk factors, but the mechanism of this association is unclear. We sought to determine the effects of the MS on myocardial and vascular function and cardiorespiratory fitness in 393 subjects with significant risk factors but no cardiovascular disease and negative stress echocardiographic findings. Myocardial function was assessed by global strain rate, strain, and regional systolic velocity (s(m)) and diastolic velocity (e(m)) using tissue Doppler imaging. Arterial compliance was assessed using the pulse pressure method, involving simultaneous radial applanation tonometry and echocardiographic measurement of stroke volume. Exercise capacity was measured by expired gas analysis. Significant and incremental variations in left ventricular systolic (s(m), global strain, and strain rate) and diastolic (e(m)) function were found according to the number of components of MS (p <0.001). MS contributed to reduced systolic and diastolic function even in those without left ventricular hypertrophy (p <0.01). A similar dose-response association was present between the number of components of the MS and exercise capacity (p <0.001) and arterial compliance. The global strain rate and e(m) were independent predictors of exercise capacity. In conclusion, subclinical left ventricular dysfunction corresponded to the degree of metabolic burden, and these myocardial changes were associated with reduced cardiorespiratory fitness. Subjects with MS who also have subclinical myocardial abnormalities and reduced cardiorespiratory fitness may have a higher risk of cardiovascular disease events and heart failure.