Cardiovascular magnetic resonance derived pulmonary capillary wedge pressure in beta-thalassemia major: Clinical correlates and association with cardiac complications

Background: This cross-sectional study explored the association of cardiovascular magnetic resonance (CMR)-derived pulmonary capillary wedge pressure (PCWP) with demographic characteristics, clinical data, CMR findings, and cardiac complications (heart failure, arrythmias, and pulmonary hypertension) in patients with beta-thalassemia major (β-TM). Methods: We included 292 β-TM patients (151 females, 36.72 ± 11.76 years) consecutively enrolled in the Extension-Myocardial Iron Overload in Thalassemia project. Iron overload was quantified by T2* technique and biventricular function parameters and atrial dimensions by cine images. Macroscopic myocardial fibrosis was detected by late gadolinium enhancement technique. CMR-derived PCWP was calculated using a previously published formula that incorporates left ventricular mass and either biplane left atrial volume (LAV) or monoplane left atrial area (LAA). Results: Both LAV PCWP and LAA PCWP were significantly higher in males than in females, while the sex-specific LAV PCWP was comparable between the two sexes. All PCWP parameters were associated with aging and splenectomy. No significant differences in PCWP parameters were observed between patients with and without myocardial iron overload. Conversely, β-TM patients with myocardial fibrosis showed significantly higher generic and sex-specific LAV PCWP. Patients with cardiac complications exhibited significantly higher LAV PCWP, LAA PCWP, and sex-specific LAV PCWP compared to those without cardiac complications. Conclusion: In β-TM patients, CMR-derived PCWP was elevated in those with myocardial fibrosis and cardiac complications, suggesting its potential as a useful non-invasive marker for cardiovascular risk assessment in.