Introduction: The goal of this study was to assess whether changes in noninvasive left ventricular end-systolic elastance (Ees) during isometric effort at baseline could contribute to an early estimation of 6-month follow-up response to cardiac resynchronization therapy (CRT) in heart failure (HF) patients.
Background: Ees is a major determinant of cardiac systolic function and ventricular-arterial interaction. It can be reliably estimated from simple noninvasive measurements. The isometric effort is useful in quantifying left ventricular performance and hemodynamic reserve in patients with heart diseases.
Methods: We examined 41 HF patients (29 male, 66±17 years, LVEF 27±6%) undergoing CRT. At baseline, each patient underwent a noninvasive continuous beat-to beat blood pressure monitoring by Nexfin system and an echocardiographic assessment to determine noninvasive Ees (Chen et al., 2001), at rest and during isometric effort. At 6-month follow-up, LV reverse remodelling was investigated. CRT patients were considered responders when an (absolute) improvement in LV ejection fraction (EF) ≥ 5% occurred.
Results: At 6-month follow-up, 30 (71%) patients were responders to CRT and 11 (26%) non-responders (mean LVEF 40±7% vs 29±5%, respectively). In responders, mean baseline Ees at rest was 0.80±0.62 mmHg/ml and it significantly increased at the third minute of the isometric effort compared to the resting condition (1.085 mmHg/ml, p=0.012). In non-responders, mean baseline Ees at rest was 0.88±0.54 mmHg/ml and it did not significantly change at the third minute of the isometric exercise (p=0.166). No significant differences were observed between the two groups in absolute baseline Ees values both at rest (p=0.678) and during isometric exercise (p=0.488).
Conclusions: Baseline changes in noninvasive Ees during isometric effort allow to identify responders to CRT at 6-month follow-up.