# Myocardial extracellular volume fraction with spectral detector computed tomography for risk stratification in non-ischemic heart failure

## TL;DR

This study shows that a new CT scan method can measure heart tissue changes in non-ischemic heart failure patients, helping predict their risk of complications.

## Contribution

The study introduces a novel CT-based method for measuring extracellular volume fraction in non-ischemic heart failure patients.

## Key findings

- CT-ECV measurements using SDCT showed no significant difference compared to CMR-ECV.
- Higher CT-ECV was observed in non-ischemic heart failure patients compared to controls.
- CT-ECV was significantly associated with worse survival outcomes in non-ischemic heart failure patients.

## Abstract

To validate the feasibility of using late iodine enhancement (LIE)-derived ECV on iodine density images using spectral detector computed tomography (SDCT; CT-ECV) and to assess the potential of CT-ECV for risk stratification among patients with non-ischemic heart failure (NIHF).

Forty-five subjects who underwent cardiac SDCT and CMR were included in the validation group to calculate and compare CT-ECV with CMR-ECV to validate CT-ECV feasibility. Another 117 subjects (82 patients with NIHF, 35 controls) who underwent SDCT were included in the experimental group to explore the potential of CT-ECV for risk stratification. ECV was measured via iodine density images and CMR T1 mapping in accordance with American Heart Association 16-segment models.

In the validation group, there was no significant difference between CT-ECV and CMR-ECV (P = 0.293), with an insignificant bias. In the experimental group, CT-ECV in patients with NIHF was significantly higher than in controls (P < 0.05). In 82 patients with NIHF, CT-ECV in HFrEF ( HF with reduced ejection fraction: LVEF ≤ 40%) patients was statistically higher than that of HFmEF (HF with mildly reduced ejection fraction: LVEF 41–49%) and HFpEF (HF with preserved ejection fraction: LVEF ≥ 50%) patients (P < 0.05) and a significant difference among patients with NIHF with varied New York Heart Association classes (all P < 0.05); In addition, Kaplan–Meier survival curves and Log-rank test demonstrated that NIHF patients with CT-ECV ≥ 31.29% had higher probability of MACE than NIHF patients with CT-ECV < 31.29% (P < 0.001).

LIE-derived CT-ECV on iodine density images using SDCT is a promising practical alternative to CMR-ECV, with the potential to assist with risk stratification among patients with NIHF.

In the assessment of non-ischemic heart failure, inclusion of late iodine enhancement to obtain ECV in CCTA examination may play a valuable role in future risk assessment in this clinical setting.

The online version contains supplementary material available at 10.1007/s11547-025-02002-1.