# Coronary artery volume to left ventricular myocardial mass ratio in detecting primary microvascular angina: a retrospective observational study in Chinese population

## TL;DR

This study explores whether a specific ratio derived from CT scans can help detect a heart condition called primary microvascular angina in the Chinese population.

## Contribution

The study evaluates the V/M ratio as a potential biomarker for PMVA in a Chinese population, a novel application in this ethnic group.

## Key findings

- PMVA patients had significantly lower average V/M ratio compared to controls.
- Vessel-specific V/M was significantly lower in left anterior descending and left circumflex arteries in PMVA patients.
- There was no significant difference in CT-FFR values between PMVA patients and controls.

## Abstract

The ratio of coronary artery volume to left ventricular myocardial mass (V/M) reflects the hemodynamic association between epicardial coronary arteries and myocardium. Evidence suggests a significant decrease in V/M among patients with primary microvascular angina (PMVA). However, V/M values may be influenced by anatomic and physiological varieties, necessitating independent evaluation in different ethnic groups. We aimed to explore the potential of V/M in predicting PMVA in Chinese population.

We conducted a retrospective case-control analysis on 23 PMVA patients and 25 controls matched by age, sex, body mass index, smoking history, hypertension, diabetes, and dyslipidemia. For each patient, the computed tomography (CT) images were three-dimensionally reconstructed to calculate patient-specific V/M and vessel-specific V/M, as well as CT-derived fractional flow reserve (CT-FFR). The results in both groups were compared using t-test or Mann-Whitney U test.

Compared to the control group, the PMVA group had significantly higher total myocardial mass and lower average V/M (P < 0.05 for both). Regarding vessel-specific V/M, PMVA group had significantly lower values of left anterior descending artery and left circumflex artery (P < 0.05 for both), with no significant inter-group difference in right coronary artery (P > 0.05). There was no significant difference between two groups in vessel-specific CT-FFR (P > 0.05 for all).

The abnormally decreased V/M value may serve as a potential biomarker of PMVA in Chinese population.