CONGRESS ABSTRACT

Degenerative aortic stenosis is the most common valvular heart disease and can cause severe concentric remodeling, diastolic dysfunction, and atrial fibrillation. These manifestations are also observed in wild-type transthyretin cardiac amyloidosis (TTR-CA), a restrictive cardiomyopathy with a poor prognosis. Studies have considered the coexistence of TTR-CA and low-flow, low-gradient aortic stenosis with normal left ventricular ejection fraction, emphasizing the importance of screening patients suspected of having both conditions due to the different management and prognosis. TTR-CA can be accurately detected through isotope scintigraphy, such as 99mTc-DPD, without the need for myocardial biopsies. Our study aims to investigate the coexistence of aortic stenosis (AS) and TTR-CA, identifying clinical, echocardiographic, and laboratory criteria that could suggest the simultaneous presence of both diseases. We retrospectively analyzed 81 patients (82±7 years, 85% men) who underwent 99mTc-DPD scintigraphy for suspected TTR-CA with or without moderate or severe AS via transthoracic echocardiography. Eight patients with AS tested positive for TTR-CA (group 1=10%), 27 without AS tested positive (group 2=34%), and 46 with AS tested negative (group 3=57%). In patients with TTR-CA, with or without AS, the prevalence of arrhythmias is high (80%), and carpal tunnel syndrome surgery is common (20%). Patients with only TTR-CA, compared to those with only AS, showed significant differences in the interventricular septum thickness (19.58 vs 14.5mm, p<0.001) and left ventricular posterior wall thickness (14.7 vs 11.46mm, p<0.001). Patients with TTR-CA and AS, compared to those with only AS, showed significantly greater thickness of the interventricular septum (21.00 vs 14.5mm, p<0.001), left ventricular posterior wall (15.17 vs 11.46mm, p=0.0018), and lower E-wave deceleration time (154.5 vs 225.3 ms, p=0.060). NT-proBNP levels were highest in patients with TTR-CA and AS, significantly different from the other groups (1 vs 2: 32918.00 vs 9164.18 ng/dl, p=0.006; 1 vs 3: 32918.00 vs 4690.25 ng/dl, p=0.001). Conclusion: In our study group, TTR-CA has a prevalence of 15% in patients with moderate or severe AS. Clinical, echocardiographic criteria and NT-proBNP plasma levels can alert for the coexistence of the two pathologies.