Reproducibility of bolus versus continuous thermodilution for assessment of coronary microvascular function in patients with ANOCA
Authors' conclusion
In the assessment of coronary microvascular function, continuous thermodilution demonstrated significantly less variability on repeated measurements than bolus thermodilution.
Study context
- Population
- Patients with angina and non-obstructive CAD (ANOCA) at angiography; measurements in LAD
- Participants
- 102 patients
- Comparison
- Continuous vs bolus intracoronary thermodilution
- Primary endpoint
- Reproducibility (variability on duplicate measurements) of bolus and continuous thermodilution
Methodological detailsrandomised order (1:1), duplicate measurements
- Randomised order (1:1)
- Duplicate measurements
Primary result
As reported in the abstract
Variability of repeated measurements
| Group | Coronary flow reserve (CFR) variability | Microvascular resistance reserve (MRR) variability | Index of microcirculatory resistance (IMR) variability |
|---|---|---|---|
| Continuous | 12.7±10.4% | 12.4±10.1% | |
| Bolus | 31.26±24.85% | 24.2±19.3% |
Coronary flow reserve (CFR) variability
Continuous12.7±10.4%
Bolus31.26±24.85%
Microvascular resistance reserve (MRR) variability
Continuous12.4±10.1%
BolusNot reported in the abstract
Index of microcirculatory resistance (IMR) variability
ContinuousNot reported in the abstract
Bolus24.2±19.3%
- Continuous vs Bolus: P < 0.001 — CFRcont vs CFRbolus variability
- Continuous vs Bolus: P < 0.001 — MRR vs IMR variability
Further findings
| Outcome | Continuous | Bolus | P value |
|---|---|---|---|
| CFRCFRcont significantly lower | 2.63 (SD 0.65) | 3.29 (SD 1.17) | P < 0.001 |
Correlation between MRR and IMR
- No correlation between MRR and IMR: r
- 0.1
- 95% CI
- −0.09 to 0.29
- P
- P = 0.305
Fractional flow reserve (FFR)
- Mean FFR
- 0.86±0.06
Original publication
Reproducibility of bolus versus continuous thermodilution for assessment of coronary microvascular function in patients with ANOCA. EuroIntervention. Published 5 June 2023. doi:10.
Summarised from the published abstract; every number is checked against it