OBJECTIVE The tricuspid annular plane systolic excursion/systolic pulmonary artery pressure (TAPSE/SPAP) ratio is a noninvasive surrogate of right ventricular to pulmonary circulation that has prognostic implications in patients with heart failure (HF) or pulmonary hypertension. Our purpose was to evaluate the prognostic value of the TAPSE/SPAP ratio in patients with cardiac amyloidosis. METHODS We used the database of the AMIGAL study, a prospective, observational registry of patients with cardiac amyloidosis recruited in 7 hospitals of the Autonomous Community of Galicia, Spain, from January 1, 2018 to October 31, 2022. We selected patients whose baseline TAPSE/SPAP ratio was calculated with transthoracic echocardiography. Long-term survival and survival free of HF hospitalization were assessed by means of 5 different multivariable Cox regression models. Median follow-up was 680 days. RESULTS We studied 233 patients with cardiac amyloidosis, among whom 209 (89.7%) had transthyretin type. The baseline TAPSE/SPAP ratio correlated significantly with clinical outcomes. Depending on the multivariable model considered, the adjusted hazard ratios estimated per 0.1mm/mmHg increase of baseline TAPSE/SPAP ratio ranged from 0.76 to 0.84 for all-cause mortality. Similarly, the ratios for all-cause mortality of HF hospitalization ranged from 0.79 to 0.84. The addition of the baseline TAPSE/SPAP ratio to the predictive model of the United Kingdom National Amyloidosis Centre resulted in an increase in Harrell's c-statistic from 0.662 to 0.705 for all-cause mortality and from 0.668 to 0.707 for all-cause mortality or HF hospitalization. CONCLUSIONS Reduced TAPSE/SPAP ratio is an independent adverse prognostic marker in patients with cardiac amyloidosis.