Abstract 17041: Increased Transvalvular Gradients Precede Clinical Diagnosis of Bioprosthetic Valve Thrombosis

Abstract

Introduction: Bioprosthetic valve thrombosis (BPVT) is increasingly being recognized as a cause of prosthetic valve dysfunction within the first years after surgical implantation. However, in the absence of changes in clinical status, current guidelines recommend cardiac imaging only after 10 years post bioprosthetic valve implantation . Hypothesis: We hypothesized that an increase in prosthetic valve gradient is detectable months before a formal diagnosis of symptomatic BPVT. Methods: Eighty-three patients diagnosed with BPVT and treated medically at our institution between 2002 and 2017 were retrospectively identified. Transvalvular gradients recorded on TTE immediately post implantation, at time of clinical BPVT diagnosis, and within a 12-month period prior to BPVT diagnosis were available in 45 patients: 18 for the aortic position, 11 for mitral, and 16 for tricuspid. When more than one study was conducted in the 12 months’ timeframe, the latest value was used in the analysis. Data are reported as mean (95% CI). Results: For all valve positions, an increased gradient was detectable within 12 months prior to formal BPVT diagnosis: mean increase vs. baseline of 17 (10-23) mmHg, p < 0.0001 for aortic prostheses; 5 (2-8) mmHg, p = 0.004 for mitral prostheses, and 2 mm Hg (1-3) mmHg, p = 0.003 for tricuspid prostheses. The figure presents the evolution of prosthetic valve gradients (normalized to the baseline, immediately post-implantation value) in patients with aortic (left), mitral (middle), and tricuspid (right) valve . Conclusions: Elevated gradients precede formal clinical diagnosis of BPVT. Closer monitoring of transvalvular gradients may prove useful for BPVT diagnosis before patients become symptomatic. With recent evidence supporting the efficacy of anticoagulant therapy in BPVT, earlier diagnosis may lead to an increased rate of response and better clinical outcomes.