Deceleration time of left ventricular outflow tract flow as a simple surrogate marker for central haemodynamics at
Insights
Prolonged deceleration time corrected for heart rate (DTc) of left ventricular outflow tract (LVOT) flow indicates higher central systolic blood pressure and arterial stiffness at rest and during exercise. This finding offers new insights into cardiovascular assessment.
Area of Science:
- Cardiovascular Physiology
- Hemodynamics
- Echocardiography
Background:
- Left ventricular outflow tract (LVOT) flow dynamics are underutilized in assessing central hemodynamics despite systolic afterload.
- Understanding the relationship between LVOT flow and arterial properties is crucial for cardiovascular health assessment.
Purpose of the Study:
- To investigate the association between LVOT flow parameters and central systolic blood pressure (BP) and arterial compliance.
- To evaluate these relationships at rest and during exercise in individuals with normal LV systolic function.
Main Methods:
- 258 subjects with normal LV systolic function underwent simultaneous stress echocardiography and arterial tonometry.
- Deceleration time corrected for heart rate (DTc) was calculated from LVOT flow.
- Central systolic BP, augmentation index (AIx@75), and pulse wave velocity (PWV) were measured.
Main Results:
- DTc showed significant independent associations with central systolic BP and AIx@75 at rest and during peak exercise.
- Prolonged DTc correlated positively with PWV, indicating a link with arterial stiffening.
- These associations were consistent in both resting and exercise conditions.
Conclusions:
- Extended DTc of LVOT flow is a marker for elevated central systolic BP and increased arterial stiffness.
- Central aortic pressures and arterial stiffness influence LVOT flow DTc.
- DTc may serve as a valuable non-invasive parameter for assessing central hemodynamics and arterial stiffness.
Background:
The shape and duration of left ventricular outflow tract (LVOT) flow has not been applied to assess the central haemodynamics, although LVOT flow is confronted with afterload of arterial system during systole. The aim of this study was to evaluate whether the LVOT flow parameters are related with central systolic blood pressure (BP) and arterial compliance at rest and as well as during exercise.
Methods:
We studied 258 subjects (175 females, age 61 ± 11 years) with normal left ventricular (LV) systolic function who underwent supine bicycle stress echocardiography and arterial tonometry simultaneously at rest and at peak exercise. Deceleration time (DT) of LVOT flow and RR interval were measured and deceleration time corrected for heart rate (DTc) was calculated. Peripheral and central haemodynamic parameters including systolic and diastolic BP, and augmentation index at a heart rate of 75 (AIx@75) were assessed using radial artery tonometry. Carotid femoral pulse wave velocity (PWV) was measured.
Resultresults:
Deceleration time corrected for heart rate was independently associated with central systolic BP and AIx@75 at rest (P < 0.001 and 0.006). Similarly, it also showed significant independent correlations with central systolic BP and AIx@75 during peak exercise (P = 0.006 and P = 0.021). In addition, DTc which measured both at rest and at peak exercise demonstrated significant positive correlations with PWV, suggesting association of prolonged DTc with arterial stiffening (P = 0.023 and P = 0.005).
Conclusion:
Prolongation of LVOT flow DTc represents raised central systolic BP and increased arterial stiffness not only at rest but also during exercise. Therefore, central aortic pressures and arterial stiffness influence the DT of LVOT flow at rest as well as during exercise in individuals with normal LV systolic function.
