Left Ventricular Longitudinal Peak Strain Research Articles

Metabolic syndrome and myocardium steatosis in subclinical type 2 diabetes mellitus: a 1H-magnetic resonance spectroscopy study

BackgroundMetabolic syndrome (MetS) is a cluster of metabolic abnormalities that collectively cause an increased risk of type 2 diabetes mellitus (T2DM) and nonatherosclerotic cardiovascular disease. This study aimed to evaluate the role of myocardial steatosis in T2DM patients with or without MetS, as well as the relationship between subclinical left ventricular (LV) myocardial dysfunction and myocardial steatosis.Methods and materialsWe recruited 53 T2DM patients and 20 healthy controls underwent cardiac magnetic resonance examination. All T2DM patients were subdivide into two group: MetS group and non-MetS. LV deformation, perfusion parameters and myocardial triglyceride (TG) content were measured and compared among these three groups. Pearson’s and Spearman analysis were performed to investigate the correlation between LV cardiac parameters and myocardial steatosis. The receiver operating characteristic curve (ROC) was performed to illustrate the relationship between myocardial steatosis and LV subclinical myocardial dysfunction.ResultsAn increase in myocardial TG content was found in the MetS group compared with that in the other groups (MetS vs. non-MetS: 1.54 ± 0.63% vs. 1.16 ± 0.45%; MetS vs. normal: 1.54 ± 0.63% vs. 0.61 ± 0.22%; all p < 0.001). Furthermore, reduced LV deformation [reduced longitudinal and radial peak strain (PS); all p < 0.017] and microvascular dysfunction [increased time to maximum signal intensity (TTM) and reduced Upslope; all p < 0.017)] was found in the MetS group. Myocardial TG content was positively associated with MetS (r = 0.314, p < 0.001), and it was independently associated with TTM (β = 0.441, p < 0.001) and LV longitudinal PS (β = 0.323, p = 0.021). ROC analysis exhibited that myocardial TG content might predict the risk of decreased LV longitudinal myocardial deformation (AUC = 0.74) and perfusion function (AUC = 0.71).ConclusionMyocardial TG content increased in T2DM patients with concurrent MetS. Myocardial steatosis was positively associated with decreased myocardial deformation and perfusion dysfunction, which may be an indicator for predicting diabetic cardiomyopathy.

Influence of the body position on the systolic speckle-tracking derived left and right ventricular function indexes of ultra-trailers

Preload is prone to vary during ultra long duration exercise (ULDE) and this can complicate the analysis of left ventricular (LV) and right ventricular (RV) function under such conditions. We studied LV and RV contractility indexes while preload conditions were changed. Twenty-two healthy male amateur ultra trailers (mean age 47) underwent serial echocardiographic assessments in three positions at rest: left-side decubitus in the standard position (P1), head-up and legs down (P2) then in the Trendelenburg position (P3). Heart rate (HR) and systolic blood pressure (SBP) were monitored. Preload was estimated by the biplane LV end diastolic volume (LV-EDV). Statistical analyses were conducted using repeated measures ANOVA. HR and SBP did not vary. LV-EDV was significantly greater in P3 than in P2 ( P = 0.004) and in P1 ( P = 0.001). LV Radial Peak Strain (LV-RPS) and LV Circumferential Peak Strain (LV-CPS) did not change. LV Longitudinal Peak Strain (LV-LPS) was greater in P3 than in P2 ( P < 0.01) and greater in P1 than in P2 ( P < 0.001). RV Longitudinal Peak Srain (RV-LPS) was greater in P3 than in P2 ( P < 0.03). The LV Longitudinal Strain Rate (LV-LSR), the LV Circumferential Strain Rate (LV-CSR) and the RV Longitudinal Strain Rate (RV-LSR) were not modified by the change of body position ( Table 1 ). LV-LSR, LV-CSR and RV-LSR as well as LV-RPS and LV-CPS were not influenced by the body position. These latter ventricular indexes seem to be less preload dependent than LV-LPS and RV-LPS and may be favored when assessing LV and RV function during ULDE.

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

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. 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. 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). 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.