Systemic-to-pulmonary collateral flow associations with antegrade pulmonary flow in single ventricle patients: insights from cardiac magnetic resonance imaging

Anna Yanovskiy; Laura Martelius; Nicolina Nyman; Teemu Vepsäläinen; Ilkka Mattila; Otto Rahkonen; Tiina Ojala

doi:10.3389/fcvm.2024.1304087

Systemic-to-pulmonary collateral flow associations with antegrade pulmonary flow in single ventricle patients: insights from cardiac magnetic resonance imaging

Front Cardiovasc Med. 2024 Feb 22:11:1304087. doi: 10.3389/fcvm.2024.1304087. eCollection 2024.

Authors

Anna Yanovskiy^#¹, Laura Martelius^#¹, Nicolina Nyman², Teemu Vepsäläinen², Ilkka Mattila³, Otto Rahkonen², Tiina Ojala⁴

Affiliations

¹ HUS Medical Imaging Center, Helsinki University Hospital, University of Helsinki, Helsinki, Finland.
² Department of Pediatric Cardiology, Children's Hospital, Helsinki University Hospital and University of Helsinki, Helsinki, Finland.
³ Pediatric Cardiac Surgery, Children's Hospital, Helsinki University and Helsinki University Hospital, Helsinki, Finland.
⁴ Department of Pediatric Cardiology, Children's Hospital, HUS Medical Imaging Center, Helsinki University Hospital and University of Helsinki, Helsinki, Finland.

^# Contributed equally.

Abstract

Purpose: In the palliated single ventricle anomalies, a considerable amount of the aortic flow may be absorbed by the systemic-pulmonary collateral flow (SPCF), which can be noninvasively assessed by cardiac magnetic resonance (CMR). The aims of this study were to (1) identify factors associated with SCPF in pediatric single ventricle patients, and (2) establish a cutoff values indicating an association between SCPF and a reduction in antegrade pulmonary flow.

Methods: A retrospective single-tertiary-center cohort study included 158 consecutive CMR studies of patients with a single ventricle. In the uni- and multivariable analysis, SPCF was presented as a percentage of the total pulmonary venous flow (SPCF_%PV). The minimal clinically important difference in Q_P/Q_S ratios was estimated as ≥0.50, and an optimal cutoff value was defined using the receiver operating characteristic (ROC) curve.

Results: SPCF_%PV was significantly smaller in the post-total cavopulmonary connection (TCPC) group than in the pre-TCPC patients (p < 0.001). The patient's higher age and a higher antegrade pulmonary flow were associated with a lower SPCF_%PV. A negative weak association was observed between the SPCF_%PV and systemic saturation (r = -0.39, p < 0.001). SPCF_%PV did not associate with ventricular volumes nor ejection fraction. The SPCF_%PV was significantly smaller in patients that were palliated primarily with a pulmonary artery banding compared to those palliated with a BT-shunt (p = 0.002) or RV-PA- shunt (p = 0.044). In the ROC analysis, for pre-TCPC patient's, a cutoff of SPCF_%PV 42% yielded a sensitivity of 100% and specificity of 80% for significantly reduced antegrade pulmonary flow (AUC 0.97). In the post-TCPC group, the optimal SPCF_%PV cutoff was 34% (sensitivity 100%, specificity 98%, AUC 0.99).

Conclusion: SPCF results in a considerable left-to-right shunt, which subsequently diminishes spontaneously after TCPC. Our findings indicated that for pre-TCPC patients, an SPCF%PV threshold of 42% (sensitivity 100%, specificity 80%), and for the post-TCPC group, a threshold of 34% (sensitivity 100%, specificity 98%) were effective in identifying reduced antegrade pulmonary flow.

Keywords: PVRI; cardiac magnetic resonance; pulmonary flow; single ventricle; systemic to pulmonary collateral flow.

Grants and funding

The author(s) declare financial support was received for the research, authorship, and/or publication of this article.