Hypo-attenuated leaflet thickening after Perceval sutureless bioprosthesis implantation

Modern multi-slice computed tomography (CT) has increased the detection of hypo-attenuated leaflet thickening (HALT). Furthermore, HALT's impact on transcatheter or surgical biological aortic valve (AV) prostheses has attracted attention. However, few reports on HALT in sutureless bioprostheses exist. Herein, we report a case of early structural valve deterioration due to HALT after AV replacement (AVR) with a Perceval bioprosthesis, which improved after anticoagulation therapy. A 79-year-old man admitted to our hospital with paroxysmal atrial fibrillation (PAF) during hemodialysis was also diagnosed with AV stenosis and, coronary artery disease, and PAF. He underwent AVR, coronary artery bypass grafting, and left atrial appendage resection. Although the postoperative course was uneventful with dual antiplatelet therapy, postoperative enhanced CT revealed HALT with reduced leaflet motion, and echocardiography showed an increased transvalvular pressure gradient. After using warfarin with target prothrombin time-international normalized ratio of 2-2.5 and/or heparin with target activated partial thromboplastin time of 45-60 s, the HALT disappeared with an improved transvalvular pressure gradient without any thromboembolic events.

Quantification of hypo-attenuated leaflet thickening after transcatheter aortic valve implantation: clinical relevance of hypo-attenuated leaflet thickening volume

AIMS

Our aim was to establish an objective, quantitative methodology for volumetric hypo-attenuated leaflet thickening (HALT) diagnosis and evaluate its clinical significance.

METHODS AND RESULTS

We prospectively enrolled 144 patients who underwent transcatheter aortic valve implantation (TAVI) between 2011 and 2016. At inclusion, cardiac computed tomography angiography (CTA), transthoracic echocardiography, and brain magnetic resonance imaging (MRI) were performed. We quantified HALT on CTA datasets by segmenting the inner volume of TAVI frame at the level of leaflets and extracted voxels between a threshold of -200 to 200 HU based on prior recommendation. The median HALT volume was 72 [inter-quartile range (IQR): 1-154] mm3 (intra- and inter-reader agreement: intra-class correlation coefficient = 0.92 and 0.94, respectively) and 79% (n = 87/111) of the patients had HALT >0 mm3. In multivariate linear regression, oral anti-coagulation (β: -0.32; 95% CI: -0.62 to -0.01; P = 0.004) and history of myocardial infarction (β: 0.32; 95% CI: 0.01-0.63; P = 0.043) were associated with HALT quantity. Log-transformed HALT volume was associated with elevated (>13 mmHg) aortic mean gradient (AMG, OR: 12.85; 95% CI: 1.96-152.93; P = 0.021) and moderate-to-severe valvular degeneration (AMG ≥ 20 mmHg or ΔAMG ≥ 10 mmHg; OR: 10.56; 95% CI: 1.44-148.71; P = 0.046) but did not predict ischaemic brain lesions on MRI or all-cause death after a median follow-up of 29 (IQR: 11-29) months (all P > 0.05).

CONCLUSION

Through systematic analysis of asymptomatic patients with TAVI, an objective and reproducible methodology was feasible for volumetric measurement of HALT. Anti-coagulation might have a protective effect against HALT. Ischaemic brain lesions and all-cause death were not associated with HALT; nevertheless, it might deteriorate prosthesis function due to its association with elevated AMG.

CLINICAL TRIAL REGISTRATION

http//:www.ClinicalTrials.gov; NCT02826200.

Effect of concomitant aortic regurgitation on early hypo-attenuated leaflet thickening after transcatheter aortic valve replacement in patients with symptomatic severe aortic stenosis

OBJECTIVE

We hypothesize that different degree of pre-existing aortic regurgitation (AR) may affect the presence of hypo-attenuated leaflet thickening (HALT) after transcatheter aortic valve replacement (TAVR).

BACKGROUND

The mechanism of the presence of HALT post-TAVR is not fully understood.

METHODS

We retrospectively evaluated the post-procedural multi-slice computed tomography (MSCT) before discharge for evidence of HALT. Patients were grouped according to the degree of pre-existing AR. Baseline, native anatomy and procedure details were compared, then multivariate regression was performed.

RESULTS

MSCT analyzed was performed at a median of 6 days post-TAVR in 179 patients. HALT was detected in 10.6% of patients. After adjusting for variables that were significantly different between groups, pre-existing ≥ moderate AR was protective to the risk of HALT (OR 0.15, 95% CI 0.03-0.84, p = .03). Stratifying for factors that might explain the impact of pre-existing AR on HALT, patients with a small Sinus of Valsalva, non-eccentric remodeling and receiving a large bioprosthesis experienced a sevenfold higher risk for HALT (OR 7.16, 95% CI 2.05-25.08, p = .002).

CONCLUSIONS

Patients underwent TAVR with pre-existing ≥ moderate AR appeared to experience a lower incidence of early HALT compared to those patients with less than moderate AR, which may be explained by a larger Sinus of Valsalva and a higher proportion of LV eccentric remodeling.