Cardiac MRI-guided therapeutics in ischemic cardiomyopathy: impact on heart-team consensus and outcomes.

AIMS: Our study aims to evaluate the influence of myocardial viability on therapeutic decision-making using cardiac MRI (CMR) and assess agreement and variability in heart-team therapeutic recommendations across different heart teams.

METHODOLOGY: We included patients who underwent coronary angiography and CMR between January 2022 and January 2024 at a tertiary cardiac center. The revascularization strategy was independently determined by heart teams from four different centers, both before and after a review of CMR. The impact of CMR on therapeutic decisions was evaluated with a follow-up for long-term outcomes, while decision concordance before and after CMR was assessed using Cohen's kappa statistics. We calculated a novel residual viable syntax score by incorporating the myocardial viability into the residual syntax score.

RESULTS

Sixty-four patients were recruited. Indications for coronary angiography included ST elevation myocardial infarction (23, 36%), NSTEMI (15, 23.4%), unstable angina (7, 10.9%), and chronic coronary syndrome with limiting symptoms (19, 29.7%). Fifty-five (86%) patients had moderate to severe LV dysfunction. A proportion of 32.8% of the patients underwent revascularization in the study population in the form of coronary artery bypass grafting or percutaneous coronary intervention, while the rest were managed medically. Incorporation of CMR findings improved the consistency of treatment decisions across heart teams (Δκ =  + 0.114, 95% confidence interval 0.01-0.22); however, these estimates should be interpreted cautiously because a total of 512 recommendations arose from repeated assessments of 64 patients and were not independent observations. Clinical-outcome analyses were exploratory because only 13 patients experienced major adverse cardiovascular outcomes during follow-up. The exploratory, non-validated residual viable SYNTAX score was not statistically significantly associated with clinical outcomes.

CONCLUSION

CMR influenced heart-team revascularization recommendations and was associated with greater agreement in therapeutic decisions. These findings, including exploratory clinical-outcome analyses, require confirmation in larger studies that use cluster-aware statistical methods.