P1791Conduction abnormalities following aortic valve intervention in patients with transthyretin cardiac amyloidosis

Abstract

Abstract Introduction Aortic Stenosis (AS) is the most common valvular heart disease in the Western world. Transcatheter aortic valve implantation (TAVI) is an alternative to surgical valve replacement in medium and high-risk patients. One of the most common complications after TAVI is conduction system disturbances including bundle branch block, complete heart block and need for permanent pacemaker implantation. Transthyretin cardiac amyloidosis (TTR–CA) is an increasingly recognized cause of heart failure that almost exclusively affects older adults. Diagnosis of TTR-CA in patients undergoing valvular intervention is relevant to understand their clinical outcomes and to discuss specific management. Objectives Occult amyloid may account for the frequent need for pacemakers among TAVR patients. We aimed to assess the correlation between intervention induced conduction abnormalities and the need for a pacemaker insertion and the presence of TTR-CA. Methods The study population included patients who had aortic valve intervention between 2011–2018. The patients underwent Tc99m-PYP scan using SPECT technology which has been shown to be valid for the diagnosis of TTR-CA. We examined the rate of conduction disorders and the need for a permanent pacemaker from patient files at the time of hospitalization and during a 24-month follow-up. Results The study population included 86 patients, mean age 78±6 years, 55% women. Twenty-nine (33%) of the participants were diagnosed as positive (VAS 2 and 3) for transthyretin cardiac amyloidosis. There were no differences in baseline characteristics with regard to age, gender, risk factors, hemoglobin and renal function between patients positive and negative for TTR CA. Conduction disorders were seen in 35 (40%) patients. Patients with TTR CA had a statistically higher prevalence of conduction disorders. Forty-two percent of TTR CA positive patients underwent peri-procedural permanent pacemaker implantation compared to 28% peri-procedural pacemaker implantations in the negative group (p=0.043). Development of a new left bundle branch block during the follow-up period was observed in 14.1% of all patients. There was a statistically significant higher rate in the positive group compared to TTR CA negative group (39.1% vs 10.9% p=0.03). Conclusions We observed a high prevalence of occult TTR-CA in older adults with aortic stenosis who underwent TAVI. We also found a high prevalence of conduction abnormalities following TAVI in patients with TTR CA. These findings suggest a need for more careful observation for possible conduction abnormalities and requirement for pacemaker insertion in these patients. Acknowledgement/Funding None