Echocardiography for prediction of 6-month and late response to cardiac resynchronization therapy: implementation of stress echocardiography and comparative assessment along with widely used dyssynchrony indices.

Non-response cardiac resynchronization therapy (CRT) remains an issue, despite the refinement of selection criteria. The purpose of this study was to investigate the role of stress echocardiography along with dyssynchrony parameters for identification of CRT responders or late responders. 106 symptomatic heart failure patients were examined before, 6 months and 2-4 years after CRT implementation. Inotropic contractile reserve (ICR) and inferolateral (IL) wall viability were studied by stress echocardiography. Dyssynchrony was assessed by: (1) Septal to posterior wall motion delay (SPWMD) by m-mode. (2) Septal to lateral wall delay (SLD) by TDI. (3) Interventricular mechanical delay (IVMD) by pulsed wave Doppler for (4) difference in time to peak circumferential strain (TmaxCS) by speckle tracking. (5) Apical rocking (ApR) and septal flash (SF) by visual assessment. At 6 months there were 54 responders, with 12 additional late responders. TmaxCS had the greatest predictive value with an area under curve (AUC) of 0.835, followed by the presence of both ICR and viability of IL wall (AUC 0.799), m-mode (AUC = 0.775) and presence of either ApR or SF (AUC = 0.772). Predictive ability of ApR and of ICR is augmented if late responders are also included. Performance of dyssynchrony parameters is enhanced, in patients with both ICR and IL wall viability. Stress echocardiography and dyssynchrony parameters are simple and reliable predictors of 6-month and late CRT response. A stepwise approach with an initial assessment of ICR and viability and, if positive, further dyssynchrony analysis, could assist decision making.

Aortic artery distensibility shows inverse correlation with heart rate variability in elderly non-hypertensive, cardiovascular disease-free individuals: the Ikaria Study.

The aim of this study was to evaluate the relation between aortic artery distensibility, expressed by pulse pressure (PP) and autonomic nervous system function expressed by heart rate variability (HRV), among elders. During 2009, 469 individuals (50 % males, mean age 75 ± 6 years old), permanent inhabitants of Ikaria Island, were enrolled. Among several sociodemographic, bioclinical, lifestyle, and dietary characteristics, and biochemical parameters related to cardiovascular risk, a digital, standard, 12-lead electrocardiogram (ECG) and 5-min ECG monitoring were recorded. Smart ECG measurement and interpretation programs were used for the automated measurement and interpretation of ECG intervals. Autonomic nervous system tone was estimated with the HRV-standard deviation of normal to normal intervals (SDNN)-in surface ECG. Pulse pressure was calculated as the difference between systolic and diastolic blood pressures. Pulse pressure showed a positive association with age, systolic blood pressure levels, and presence of diabetes mellitus (all P < 0.001) and an inverse correlation with logSDNN. Multiadjusted logistic regression analysis revealed that 10-unit increase in SDNN values decreases by 26 % the likelihood of having PP above 70 mmHg; when the analysis was stratified according to hypertension status, the relationship remained significant only among non-hypertensive individuals. These data support the hypothesis that cardiac sympathovagal disturbance correlates with impaired elasticity properties of aorta, indicating parallel impairment in cardiac autonomic modulation and mechanical vessel wall properties in elderly non-hypertensive individuals.