Evaluation of coronary artery disease risk in liver transplant candidates using a modified CAD-LT algorithm integrated with coronary artery calcium score and coronary CT angiography

Background

Epidemiological changes in liver transplant (LT) candidates have increased the prevalence of coronary artery disease (CAD) risk factors. The CAD-LT algorithm, validated in the U.S. to guide cardiac evaluation in LT candidates, is limited by its reliance on invasive tests such as invasive coronary angiography (ICA). In the general population, coronary artery calcium scoring (CACS) and coronary computed tomography angiography (CCTA) have demonstrated high negative predictive value for clinically significant CAD. This study evaluates a modified CAD-LT (mCAD-LT) algorithm incorporating CACS and CCTA.

Methods

This prospective, single-center study enrolled LT candidates between August 2022 and January 2025. The mCAD-LT score added obesity and metabolic dysfunction-associated steatotic liver disease (MASLD) as risk factors and redefines cardiovascular risk categories as low (<7), intermediate (7–10), and high (>10).Low-risk patients (mCAD-LT <7) with CACS <100 required no further evaluation. Patients at low risk with CACS ≥100 or those with mCAD-LT ≥7 and CACS <400 underwent CCTA. If CACS ≥400, subsequent testing was determined by the mCAD-LT score: patients at intermediate risk (mCAD-LT 7-10) underwent stress echocardiography, while those at high risk (mCAD-LT >10) were referred directly to ICA (Fig. 1).

Results

Among 205 LT candidates (mean age 59 ± 7 years; 73.6% male), MASLD and alcohol-related liver disease were the predominant etiologies. Obesity was present in 21.4% (mean BMI 26.4 ± 3.6 kg/m²), and only 14.4% had no cardiovascular risk factors. Thirty-five patients (17%) were classified as low-risk (mCAD-LT <7 and CACS <100) and did not require further testing. CCTA was performed in 126 patients who either had a low mCAD-LT score with a CACS ≥100, or an intermediate/high-risk mCAD-LT score (≥7) with a CACS <400.Among 44 intermediate/high-risk patients with CACS ≥400, 18 underwent stress echocardiography and 26 were referred directly to ICA (Fig. 1). Overall, 46 ICAs (22%) were performed, detecting significant coronary stenosis in 9 cases. Seven patients underwent percutaneous coronary intervention (PCI) with drug-eluting stents (DES); two were excluded from LT due to dual antiplatelet therapy (DAPT) contraindications. One post-LT acute myocardial infarction (<1%) occurred, successfully managed with repeat PCI.

Conclusions

The mCAD-LT algorithm significantly reduced ICA use by more than 50% compared to estimates using the original CAD-LT algorithm, while maintaining a low (<1%) incidence of post-transplant cardiac events. These results support mCAD-LT as a safe, effective, and less invasive strategy for CAD risk stratification in LT candidates.