Assessment of heart's changes of elite Chinese male weightlifter by speckle tracking echocardiography / 北京大学学报(医学版)

OBJECTIVE@#To evaluate the changes of heart structure and function in elite Chinese weightlifters by spot tracking technique.@*METHODS@#Chinese elite male weightlifters (weightlifter group, n=16) and age-matched healthy men (control group, n=16) were included as subjects. Transthoracic echocardiography and speckle-tracking automatic functional imaging were used for two-dimensional myocardial strain measurements.@*RESULTS@#The thickness of septum and left ventricular (LV) posterior wall and the myocardial mass index of LV were all higher than those of the control group [(9.3±1.3) mm vs. (8.0±0.4) mm, (9.2±0.8) mm vs. (8.0±0.8) mm, (77.8±12.8) g/m2 vs. (67.8±11.2) g/m2, all P < 0.05]. Although the LV ejection fraction (LVEF) and global long axis strain value (LVGLS) were not significantly different from those in the control group, the LV mean Sm and Em reflecting the systolic and diastolic functions of the LV were lower than those in the control group (P < 0.05). Further myocardial strain analysis showed that the absolute value of the long axial strain of the basal anteroseptal and mid-inferoseptal segments of the weightlifters were significantly lower than those of the control group [|(-15.1±4.2)%|vs.|(-18.7±3.0)%|, |(-18.8±2.6)%|vs.|(-21.3±2.8)%|, all P < 0.05]. There was no significant difference in other segments. The athletes were divided into two groups according to their best performance in the National Youth Games. The athletes were divided into two sub-groups according to their performance in the National Youth Games. The thickness of the septum in the sub-group with better performance (who ranked the 1st to 8th) was larger [(10.2±1.1) mm vs. (8.5±1.0) mm, P < 0.05], and the absolute value of the long-axis strain in the mid-inferoseptal segment was lower [|(-17.1±2.1)%|vs.|(-20.4±2.1)%|, P < 0.05].@*CONCLUSION@#The thickening of septum is more obvious in the excellent weightlifters, accompanied by the decrease of myocardial systolic function. The speckle-tracking technique of echocardiography can identify the changes of the heart structure and function of elite athletes at an early stage, which may provide a basis for sports medicine supervision and the selection of excellent talents.

Excitation-Contraction Coupling Time is More Sensitive in Evaluating Cardiac Systolic Function / 中华医学杂志(英文版)

Background@#Pressure overload-induced myocardial hypertrophy is a key step leading to heart failure. Previous cellular and animal studies demonstrated that deteriorated excitation-contraction coupling occurs as early as the compensated stage of hypertrophy before the global decrease in left ventricular ejection fraction (LVEF). This study was to evaluate the cardiac electromechanical coupling time in evaluating cardiac systolic function in the early stage of heart failure.@*Methods@#Twenty-six patients with Stage B heart failure (SBHF) and 31 healthy controls (CONs) were enrolled in this study. M-mode echocardiography was performed to measure LVEF. Tissue Doppler imaging (TDI) combined with electrocardiography (ECG) was used to measure cardiac electromechanical coupling time.@*Results@#There was no significant difference in LVEF between SBHF patients and CONs (64.23 ± 8.91% vs. 64.52 ± 5.90%; P = 0.886). However, all four electromechanical coupling time courses (Qsb: onset of Q wave on ECG to beginning of S wave on TDI, Qst: onset of Q wave on ECG to top of S wave on TDI, Rsb: top of R wave on ECG to beginning of S wave on TDI, and Rst: top of R wave on ECG to top of S wave on TDI) of SBHF patients were significantly longer than those of CONs (Qsb: 119.19 ± 35.68 ms vs. 80.30 ± 14.81 ms, P < 0.001; Qst: 165.42 ± 60.93 ms vs. 129.04 ± 16.97 ms, P = 0.006; Rsb: 82.43 ± 33.66 ms vs. 48.30 ± 15.18 ms, P < 0.001; and Rst: 122.37 ± 36.66 ms vs. 93.25 ± 16.72 ms, P = 0.001), and the Qsb, Rsb, and Rst time showed a significantly higher sensitivity than LVEF (Rst: P =0.032; Rsb: P = 0.003; and Qsb: P = 0.004).@*Conclusions@#The cardiac electromechanical coupling time is more sensitive than LVEF in evaluating cardiac systolic function.

Impact of uncontrolled blood pressure on diagnostic accuracy of coronary flow reserve for detecting significant coronary stenosis in hypertensive patients / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>Impaired coronary flow reserve (CFR) in patients with hypertension may be caused by epicardial coronary stenosis or microvascular dysfunction. Antihypertensive treatment has been shown to improve coronary microvascular dysfunction. The aim of this study was to evaluate the impact of uncontrolled blood pressure (BP) on diagnostic accuracy of CFR for detecting significant coronary stenosis.</p><p><b>METHODS</b>A total of 98 hypertensive patients scheduled for coronary angiography (CAG) due to chest pain were studied. Of them, 45 patients had uncontrolled BP (defined as the office BP ≥ 140/90 mmHg (1 mmHg = 0.133 kPa) in general hypertensive patients, or ≥ 130/80 mmHg in hypertensive individuals with diabetes mellitus), and the remaining 53 patients had well-controlled BP. CFR was measured in the left anterior descending coronary artery (LAD) during adenosine triphosphate-induced hyperemia by non-invasive transthoracic Doppler echocardiography (TTDE) within 48 hours prior to CAG. Significant LAD stenosis was defined as > 70% luminal narrowing. Diagnostic accuracy of CFR for detecting significant coronary stenosis was analyzed with a receiver operating characteristic analysis.</p><p><b>RESULTS</b>CFR was significantly lower in patients with uncontrolled BP than in those with well-controlled BP (2.1 ± 0.6 vs. 2.6 ± 0.9, P < 0.01). Multivariate linear regression analysis of the study showed that the value of CFR was independently associated with the angiographically determined degree of LAD stenosis (β = -0.445, P < 0.0001) and the presence of uncontrolled BP (β = -0.272, P = 0.014). With a receiver operating characteristic analysis, CFR < 2.2 was the optimal cut-off value for detecting LAD stenosis in all hypertensive patients (AUC 0.83, 95%CI 0.75 - 0.91) with a sensitivity of 75%, a specificity of 78%, and an accuracy of 77%. A significant reduction of diagnostic specificity was observed in patients with uncontrolled BP compared with those with well-controlled BP (67% vs. 93%, P = 0.031).</p><p><b>CONCLUSIONS</b>CFR measurement by TTDE is valuable in the diagnosis of significant coronary stenosis in hypertensive patients. However, the diagnostic specificity is reduced in patients with uncontrolled BP.</p>

Value of left atrial area index for diagnosing left ventricular diastolic dysfunction in hypertensive patients with preserved left ventricular systolic function / 中华心血管病杂志

<p><b>OBJECTIVE</b>To investigate the correlation between left atrial size and left ventricular filling pressure (LVFP) and the value of left atrial size assessment on detecting diastolic dysfunction in hypertensive patients with preserved LVEF by echocardiography.</p><p><b>METHODS</b>Echocardiography was performed in 346 hypertensive patients with preserved LVEF(≥ 50%), left atrial size including left atrial diameter (LAD) and left atrial area (LAA) was measured and indexed to body surface area (LADI, LAAI). The ratio of early diastolic transmitral velocity to early diastolic mitral annular velocity (E/Em) was determined and LVFP was calculated with the formula: LVFP = 1.24×E/Em + 1.9. Patients were divided into diastolic dysfunction group [DD group, LVFP > 15 mm Hg (1 mm Hg = 0.133 kPa), n = 81] and normal diastolic function group (NDF group, LVFP ≤ 15 mm Hg, n = 265).</p><p><b>RESULTS</b>As compared to patients in NDF group, the patients in DD group had larger LA [LADI: (21.4 ± 2.6) mm/m(2) vs. (19.6 ± 2.4) mm/m(2); LAAI: (12.1 ± 2.6) cm(2)/m(2) vs. (10.4 ± 1.7)cm(2)/m(2); all P < 0.01]. LA size parameters were positively correlated with LVFP (r = 0.211-0.450, all P < 0.01), LAAI was best correlated with LVFP (r = 0.450, P < 0.01). ROC analysis showed that LAAI ≥ 11.4 cm(2)/m(2) diagnosed DD with a sensitivity of 63%, specificity of 74% and accuracy of 72%.</p><p><b>CONCLUSION</b>Left atrium dilation correlates positively with LVFP in hypertensive patients with preserved LVEF. The LAAI is a more accurate parameter for identifying patients with diastolic dysfunction in this cohort.</p>

Comparison of changes in left ventricular gene expression profiles from different cardiac hypertrophy models in rats / 生理学报

To get insights into the principles of gene expression changes during cardiac hypertrophy, three rat cardiac hypertrophy models were prepared, i.e., suprarenal abdominal aortic stenosis (SRS), arterial-vein fistula (AVF) and continuous jugular vein infusion of norepinephrine (NEi). The cardiac function and structure were analyzed by echocardiograph as well as histological examination. Total RNA of left ventricles was extracted and gene expression profiles were analyzed by cDNA microarray. SRS and NEi induced concentric cardiac hypertrophy and AVF induced eccentric hypertrophy in rats, among which NEi caused obvious cardiac fibrosis. The changes of gene expression profiles were compared comprehensively across different pathologic cardiac hypertrophy models. While gene expression profiles of different cardiac hypertrophy models compared with pairs, parts of the genes involved were found overlapped, and mostly the gene expression changed in the same direction between two models, but some of them changed in the opposite directions. Expression levels of 19 genes were found changed across all cardiac hypertrophy models, and genes relatively regulated in a specific model was also found when comparison of all the three models was carried out. Novel clues for further study might derive from the results mentioned above, and some genes might be the marker genes of cardiac hypertrophy or the targets of therapy.

Alterations of Axin protein expression during cardiac remodeling in rats / 生理学报

The purpose of the present study was to observe the expression of Axin protein during cardiac remodeling in rats. Cardiac remodeling animal models were prepared with the methods of jugular venous norepinephrine (NE)-infusion or arterial-vein fistula (AVF). The ultrasonic parameters of rat hearts were recorded before sacrifice. The expressions of Axin protein were determined by Western blot in rat hearts from different remodeling models as well as cultured cardiac fibroblasts from adult rats. Cardiac concentric hypertrophy and fibrosis was induced by 3-day jugular vein infusion of NE in rats. The expression of Axin in the left ventricles increased significantly compared with that of the control group. Cardiac eccentric hypertrophy without fibrosis was induced by A-V fistula for one week in rats, and no change in Axin protein expression in the left ventricles was observed. In cultured adult rat cardiac fibroblasts, NE treatment for 24 h increased significantly the Axin protein level. It is therefore concluded that Axin protein was expressed in rat heart and increased significantly in left ventricles during NE-induced rat cardiac remodeling, which may be relevant to cardiac fibrosis.