Intrinsic Wave Velocity Propagation:A Novel Parameter for Assessing the Effect of Anthracycline Chemotherapy Agents on Cardiac Diastolic Function in Breast Cancer Patients

Objective Anthracycline chemotherapeutic agents have significant cardiotoxicity.The present study emphasized the effect of anthracycline chemotherapy drugs on left ventricular(LV)myocardial stiffness in breast cancer patients by measuring the intrinsic wave velocity propagation(IVP),and evaluating the potential clinical value of IVP in detecting early LV diastolic function impairment.Methods A total of 68 newly diagnosed breast cancer patients,who were treated with anthracycline-based chemotherapy,were analyzed.Transthoracic echocardiography was performed at baseline(T0),and after 1,2,3,4 and 8 chemotherapeutic cycles(T1,T2,T3,T4 and T5,respectively).Then,the IVP,LV strain parameters[global longitudinal strain(GLS),longitudinal peak strain rate at systole(LSRs),longitudinal peak strain rate at early diastole(LSRe),longitudinal peak strain rate at late diastole(LSRa),and the E/LSRe ratio],and conventional echocardiographic parameters were obtained and further analyzed.A relative reduction of>15%in GLS was considered a marker of early LV subclinical dysfunction.Results Compared to the T0 stage,IVP significantly increased at the T1 stage.However,there were no significant changes in GLS,LSRs,or LSRe between the T0 and T1 stages.These parameters significantly decreased from the T2 stage.LSRa started to significantly decrease at the T5 stage,and the E/LSRe ratio started to significantly increase at the T3 stage(all P<0.05).At the T0 stage,IVP(AUC=0.752,P<0.001)had a good predictive value for LV subclinical dysfunction after chemotherapy.Conclusions IVP is a potentially sensitive parameter for the early clinical assessment of anthracycline-related cardiac diastolic impairment.

Effects of Lead on Systolic and Diastolic Cardiac Functions

In this paper, both systolic and diastolic cardiac functions were cvaluatcd in 54 lead exposed and 24 non-exposed workers by Doppler cchocardiography. With regard to systolic cardiac function, the results suggested that cardiac systolic function increased in exposed groups as a compensatory response for the effecl of lead on myocardium. To study left ventriculaf diastolic function, 2.5 MHz pulsed Doppler analyses of transmitral flow velocity were performed from apical four-chamber view. The results showed that timerelated parameters were comparable among all groups, but blood flow velocity through the mitral valve and Doppler area fractions changed significantly in lead-exposed groups as cvidenced by increased value A, decreased value E and E/A ratio. The decrease of diastolic cardiac function was more significant in lead intoxication group. It was also observed in this study that the activity in serum of thc MB isoenzyme of creatine phosphokinase (CPK-MB), one of the indices of myocardial damage, was significantly highcr in exposed group than that in control (P (0.05), and a positive correlation was found between CPK-MB activity and Pb-B. It denoted that the inereasing of lead burden leads to more release of CPK-MB from the myocardial cells and suggested the existence of slight myocardial damage, which, conceivably, might cause harm to diastolic cardiac function