Abstract
BACKGROUND: Cardiovascular magnetic resonance (CMR) offers comprehensive assessment of cardiomyopathy but lacks validated methods for estimating left ventricular filling pressure (LVFP), an important prognostic marker. Invasive pulmonary capillary wedge pressure (PCWP) measurements remain a gold standard but are impractical for routine use due to procedural risks. A CMR-modeled PCWP model offers a noninvasive alternative, but its ability to improve prognostic assessment beyond conventional markers has not been well established. We evaluated the prognostic utility of CMR PCWP in patients with non-ischemic cardiomyopathy (NICM). METHODS: NICM patients who underwent CMR between December 2008 and December 2017 were retrospectively included. CMR-modeled PCWP was calculated as: 6.1352 + (0.07204 × left atrial volume [LAV]) + (0.02256 × left ventricular mass [LVM]). The primary outcome was a composite of all-cause mortality, heart transplantation, or hospitalization for heart failure (HHF). Secondary outcomes included HHF and all-cause mortality separately. Multivariable Cox proportional hazards models assessed prognostic value. RESULTS: A total of 458 patients (mean age 53.2 years, BMI 29.3 kg/m², LVEF 32.8% ± 11.1%) were followed for a median of 3.6 years. The primary outcome occurred in 39% with PCWP ≥ 15 mmHg versus 21% with PCWP of <15 mmHg (HR 2.11, 95% CI 1.48-3.01; P-value < 0.001). CONCLUSION: CMR-modeled PCWP provides independent prognostic value providing further risk differentiation among patients traditionally classified as low-risk.