Systolic time intervals assessed from analysis of the carotid pressure waveform

Paolo Salvi*, Andrea Grillo, Isabella Tan, Giulia Simon, Lucia Salvi, Lan Gao, Matteo Rovina, Mark Butlin, Ying Yang, Erika Meneghin, Lei Meng, Andrea Faini, Edward Barin, Alessandro Pini, Renzo Carretta, Yong Huo, Alberto Avolio, Gianfranco Parati

*Corresponding author for this work

Research output: Contribution to journalArticle

2 Citations (Scopus)

Abstract

Objective: The timing of mechanical cardiac events is usually evaluated by conventional echocardiography as an index of cardiac systolic function and predictor of cardiovascular outcomes. We aimed to measure the systolic time intervals, namely the isovolumetric contraction time (ICT) and pre-ejection period (PEP), by arterial tonometry. Approach: Sixty-two healthy volunteers (age 47 ± 17 years) and 42 patients with heart failure and reduced ejection fraction were enrolled (age 66 ± 14 years). Pulse waves were recorded at the carotid artery by arterial tonometry together with simultaneous aortic transvalvular flow by Doppler-echocardiography, synchronized by electrocardiographic gating. The ICT was determined from the time delay between the electrical R wave and the carotid pressure waveform, after adjustment for the pulse transit time from the aortic valve to the carotid artery site, estimated by an algorithm based on the carotid-femoral pulse wave velocity. The PEP was evaluated by adding the electrical QR duration to the ICT. Main results: The ICT derived from carotid pulse wave analysis was closely related to that measured by echocardiography (r = 0.90, p <0.0001), with homogeneous distribution in Bland-Altman analysis (mean difference and 95% confidence interval = 0.2 from -14.2 to 14.5 ms). ICT and PEP were higher in cardiac patients than in healthy volunteers (p <0.0001). The ratio between PEP and left ventricular ejection time was related to the ejection fraction measured with echocardiography (r = 0.555, p <0.0001). Significance: The timing of electro-mechanical cardiac events can be reliably obtained from the carotid pulse waveform and carotid-femoral PWV, evaluated using arterial tonometry. Systolic time intervals assessed with this approach showed good agreement with measurements performed with conventional echocardiography and may represent a promising additional application of arterial tonometry.

Original languageEnglish
Article number084002
Pages (from-to)1-12
Number of pages12
JournalPhysiological Measurement
Volume39
Issue number8
DOIs
Publication statusPublished - 20 Aug 2018

Keywords

  • arterial tonometry
  • ejection fraction
  • isometric contraction time
  • pre-ejection period
  • pulse wave velocity
  • systolic time intervals

Cite this

Salvi, P., Grillo, A., Tan, I., Simon, G., Salvi, L., Gao, L., ... Parati, G. (2018). Systolic time intervals assessed from analysis of the carotid pressure waveform. Physiological Measurement, 39(8), 1-12. [084002]. https://doi.org/10.1088/1361-6579/aad51b