Rapid assessment of longitudinal systolic left ventricular function using speckle tracking of the mitral annulus.

BACKGROUND: Evaluation of left ventricular function (LV) is one of the most important tasks of echocardiography. Left ventricular longitudinal function has been recognized to differentiate myocardial disorders better than ejection fraction (EF) alone. But recent parameters are still dependent on image quality and time consuming. METHODS: Transthoracic echocardiography, tissue Doppler imaging, strain imaging and assessment of longitudinal function with a tissue motion annular displacement (TMAD) tracking algorithm were performed in 152 patients with various cardiac pathologies and 47 healthy volunteers in a clinical routine setting. RESULTS: Measures of longitudinal function such as LV peak systolic strain (SR, r² = 0.88, p < 0.001) and peak systolic strain rate (SRR, r² = 0.78, p < 0.001) correlated highly with TMAD. Tissue motion annular displacement was ultrafast and less time-consuming compared to strain imaging (8.2 ± 2.2 s, p < 0.001). Significantly more patients with reduced image quality could be analyzed compared to strain imaging (p < 0.001). The intra- and inter-observer variabilities were very low with 1.3 ± 1% and 1.7 ± 1.2%. Tissue motion annular displacement correlated well with clinical parameters (NYHA, r = -0.71, p < 0.001) as well as NT-proBNP (r = -0.73, p < 0.001) and identified patients with structural heart disease with a significantly higher sensitivity 92.1% and specificity 95.7% than did EF, SR, SRR or NT-proBNP (Cut-off:14.2%, p < 0.01). In a subgroup of patients with systemic light chain amyloidosis and preserved EF (>50%, n = 54), TMAD was significantly reduced, especially in those without any signs of cardiac involvement and was superior to other parameters of longitudinal function (p < 0.05). CONCLUSIONS: Tissue motion annular displacement is a rapid, sensitive and reproducible method for the assessment of LV longitudinal function, which is less dependent on image quality.

Assessment of disease severity and outcome in patients with systemic light-chain amyloidosis by the high-sensitivity troponin T assay.

Cardiac biomarkers provide prognostic information in light-chain amyloidosis (AL). Thus, a novel high-sensitivity cardiac troponin T (hs-TnT) assay may improve risk stratification. hs-TnT was assessed in 163 patients. Blood levels were higher with cardiac than renal or other organ involvement and were related to the severity of cardiac involvement. Increased sensitivity was not associated with survival benefit. Forty-seven patients died during follow-up (22.3 ± 1.0 months). Nonsurvivors had higher hs-TnT than survivors. Outcome was worse if hs-TnT more than or equal to 50 ng/L and best less than 3 ng/L. Survival of patients with hs-TnT 3 to 14 ng/L did not differ from patients with moderately increased hs-TnT (14-50 ng/L), but was worse if interventricular septum was more than or equal to 15 mm. Discrimination according to the Mayo staging system was only achieved by the use of the hs-TnT assay, but not by the fourth-generation troponin T assay. Multivariate analysis revealed hs-TnT, NT-proBNP, and left ventricular impairment as independent risk factors for survival. hs-TnT and NT-proBNP predicted survival, even after exclusion of patients with impaired renal function. Plasma levels of the hs-TnT assay are associated with the clinical, morphologic, and functional severity of cardiac AL amyloidosis and could provide useful information for clinicians on cardiac involvement and outcome.