Cardiac amyloidosis: hemodynamic profile and prognostic implications

Background: Cardiac amyloidosis (CA) is a hypertrophic phenotype cardiomyopathy characterized by a clinical presentation predominantly defined by heart failure. This study evaluates the invasive hemodynamic characteristics and their prognostic implications in consecutive patients diagnosed with CA (in its three main etiologies: light chain amyloidosis AL, transthyretin variant amyloidosis ATTRv, and transthyretin wild-type amyloidosis ATTRwt) who underwent RHC at IRCCS S. Orsola Hospital in Bologna between 1992 and December 2023. Results: A total of 274 patients were enrolled (121 [44.2%] AL, 66 [24.1%] ATTRv, and 87 [31.7%] ATTRwt). At baseline, the hemodynamic profile was characterized by elevated biventricular filling pressures and pulmonary hypertension, with a median mean pulmonary artery pressure (mPAP) of 24 mmHg [IQR: 18–30], predominantly post-capillary or combined pre- and post-capillary. The stroke volume index (SVi) was reduced, with a median of 30 mL/m² [IQR: 24–37], and the cardiac index (CI) was at the lower limit of normality, with a median of 2.4 L/min/m² [IQR: 1.9–2.8]. Patients with advanced NYHA class at presentation (III/IV) presented a more severe echocardiographic and hemodynamic profile. Invasive hemodynamic parameters showed a good correlation with echocardiographic measurements. During a median follow-up of 30 months, 159 deaths were recorded. Classic cut-offs for RAP, PCWP, mPAP, and SVi emerged as predictors of mortality in Kaplan-Meier curves. In multivariate Cox regression analysis, independent predictors of overall mortality included age at diagnosis, AL etiology, advanced NYHA functional class at presentation (III/IV), estimated glomerular filtration rate (eGFR), RAP, and SVi. Conclusions: The hemodynamic profile of patients with cardiac amyloidosis is characterized by concomitant systolic and diastolic dysfunction, elevated biventricular filling pressures, and reduced SVi. Both RAP and SVi are independently associated with mortality in this population.