Impact of different respiratory monitoring techniques on respiration-dependent stroke-volume measurements assessed by real-time magnetic resonance imaging

Hendrik Becker; Maximilian Wattenberg; Peter Barth; Kai Thorsten Laser; Wolfgang Burchert; Hermann Körperich

doi:10.1016/j.zemedi.2019.06.002

Impact of different respiratory monitoring techniques on respiration-dependent stroke-volume measurements assessed by real-time magnetic resonance imaging

Z Med Phys. 2019 Dec;29(4):349-358. doi: 10.1016/j.zemedi.2019.06.002. Epub 2019 Jun 25.

Authors

Hendrik Becker¹, Maximilian Wattenberg², Peter Barth¹, Kai Thorsten Laser³, Wolfgang Burchert¹, Hermann Körperich⁴

Affiliations

¹ Institut für Radiologie, Nuklearmedizin und Molekulare Bildgebung, Herz- und Diabeteszentrum Nordrhein-Westfalen, Universitätsklinikum der Ruhr-Universität Bochum, Georgstraße 11, 32545 Bad Oeynhausen, Germany.
² Institute of Medical Engineering, Universität zu Lübeck, Ratzeburger Allee 160, 23562 Lübeck, Germany.
³ Kinderherzzentrum und Zentrum für angeborene Herzfehler, Herz- und Diabeteszentrum Nordrhein-Westfalen, Universitätsklinikum der Ruhr-Universität Bochum, Georgstraße 11, 32545 Bad Oeynhausen, Germany.
⁴ Institut für Radiologie, Nuklearmedizin und Molekulare Bildgebung, Herz- und Diabeteszentrum Nordrhein-Westfalen, Universitätsklinikum der Ruhr-Universität Bochum, Georgstraße 11, 32545 Bad Oeynhausen, Germany. Electronic address: hkoerperich@hdz-nrw.de.

PMID: 31253380
DOI: 10.1016/j.zemedi.2019.06.002

Abstract

Purpose: Quantitative blood flow measurements in thoracic vessels are dependent on the patient's respiration due to intrathoracic pressure changes. Several registration techniques for tracing the patient's breathing curve exist exploiting various physiological characteristics. In the presented study two registration techniques were investigated to estimate the time-shift between the associated respiration curves and the impact on respiration-dependent hemodynamic measures.

Materials and methods: Using flow-sensitive real-time magnetic resonance imaging (3.0T, temporal resolution=24-26ms) data were acquired during a 13s time-interval under normal physiological (no) and forced breathing (fo) in the ascending aorta (AAo) and inferior vena cava (IVC). Breathing curves were obtained by using (1) an abdominal placed respiratory belt (=standard, RB) and (2) by applying a self-developed edge-detection software (ED). Respiration curves were divided into four intervals (end-expiration, inspiration, end-inspiration and expiration) to generate respiration-dependent stroke volumes (SVs) and cardiac indices (CIs). Data were available from 12 healthy controls (16.2±8.8yrs) and 18 Fontan-patients (18.6±7.1yrs).

Results: Respiration curves acquired with RB differs from and are shifted compared to those obtained by ED (controls: average shift=207±168ms, Fontan-patients: average shift=106±235ms). This time-shift results in statistical significant differences in cardiac indices CI_AAo,fo in controls (ΔCI_AAo,fo: expiration: +0.16L/min/m², p=0.018), in CI_IVC,no in Fontan-patients (ΔCI_IVC,no: end-expiration: +0.94L/min/m², p=0.002 and end-inspiration: -1.04L/min/m², p=0.017) and in CI_IVC,fo in Fontan-patients (ΔCI_IVC,fo: end-expiration: +1.31L/min/m², p=0.009; inspiration: -2.26L/min/m², p=0.008 and end-inspiration: -1.87L/min/m², p=0.029).

Conclusions: A time-shift between both applied respiratory tracking techniques was observed resulting in significant differences in respiration-dependent CIs, which could influence the clinical decision-making.

Keywords: Blood flow quantification; Cardiac index; Magnetic resonance imaging; Post-processing; Respiration.

MeSH terms

Humans
Magnetic Resonance Imaging* / standards
Monitoring, Physiologic / instrumentation*
Monitoring, Physiologic / methods*
Respiration
Stroke Volume*