Supplementary Appendix

Transcription

1 Supplementary Appendix This appendix has been provided by the authors to give readers additional information about their work. Supplement to: Makkar RR, Fontana G, Jilaihawi H, et al. Possible subclinical leaflet thrombosis in bioprosthetic aortic valves. N Engl J Med 2015;373: DOI: /NEJMoa (PDF updated December 2, 2015.)

2 1 Table of contents CT Imaging protocol... 3 Case selection for CT... 3 CT acquisition protocols... 3 CT analysis protocol... 4 Pulse duplicator model... 6 Figure S1: CT appearance of bioprosthetic aortic valves with normal and reduced leaflet motion... 7 Figure S2: Correlation of transesophageal echocardiogram (TEE) with computed tomography (CT) for the assessment of reduced leaflet motion in a patient with a Portico valve Figure S3: Mean aortic valve gradients in patients with and without reduced leaflet motion in the PORTICO IDE cohort Figure S4: Resolution of reduced leaflet motion of Sapien XT valve with anticoagulation Figure S5: Case example of resolution of hypoattenuating opacities and restoration of leaflet motion in Sapien XT with warfarin and reappearance of thrombus on a different leaflet on follow-up CT after discontinuation of warfarin Figure S6: Pulse duplicator model Table S1: Computed tomography and echocardiographic findings in the PORTICO IDE cohort Table S2: Antiplatelet and antithrombotic medications at the time of CT scan* Table S3: Echocardiographic and computed tomography characteristics of pooled registries Table S4: Frequency of reduced leaflet motion in different valve types in the registries... 19

3 2 Table S5: Pulse duplicator model to evaluate the effect of leaflet motion on valve gradients... 20

4 3 CT Imaging protocol Case selection for CT The PORTICO IDE mandated a sub-study of 30-day contrast CT Scans for prospectively enrolled consecutive patients who consented for contrast CT. The RESOLVE and SAVORY registries enrolled all patients consenting for contrast CT that attended the valve clinic before or after TAVR. CT acquisition protocols All acquisition protocols enabling the formal assessment of leaflet motion and thickening (PORTICO IDE and registries) employed contrast CT with retrospective gating. In the PORTICO IDE, specific machines used, acquisition protocols and doses of contrast were dictated by the treating sites. In the RESOLVE registry, contrast-enhanced CT examinations were performed using a second-generation dual-source CT system (Siemens Somatom Definition Flash; Siemens Healthcare, Erlangen, Germany). A commercially available contrast medium (Omnipaque, GE Healthcare, Little Chalfont, Buckinghamshire, United Kingdom) was used with 100 ml in each patient; bolus triggering in the ascending aorta was employed. Heart rate (HR) reduction with β- blockade was not performed, nor was dose modulation. Acquisition was in the cranio-caudal direction from the aortic arch to the diaphragm. CT was performed with a collimation of 128x0.625 mm and maximum tube current ranged was automated for each patient using Caredose (Siemens Healthcare, Erlangen, Germany) with a fixed tube potential of kV. Images were reconstructed at 0.6 mm slices with 0.3 mm overlap with iterative reconstruction for evaluation at 10% intervals within the 0-90% RR range.

5 4 In the SAVORY registry, all patients were scanned in the craniocaudal direction using a Toshiba 320-row CT scanner (Acquilion One ViSION Edition, Toshiba Medical Systems, Otawara, Japan), using a dedicated retrospective volume image protocol. Visipaque (GE Healthcare, Oslo, Norway) ml depending on weight was infused 5-6 ml/sec. The scans were initiated by real time bolus tracking in the left ventricle. The start and end position of the scan was determined by the initial scanogram; start position was defined as 20 mm cranial to the metal stent frame of the valve and end position 16 cm (maximal Z-axis coverage) caudally. An image noise standard deviation level of 30 was predefined, which resulted in a variable kv and ma between patients. The kv was set to 120 by default, if this resulted in a maximal ma the kv was raised, until a sub-maximal ma was reached. To minimize radiation exposure a dose-modulation approach was used reducing dose in the % RR-range (diastole). The contrast images were recorded by 1 rotation of the gantry at a heart rate of less than 75 bpm, 2 rotations at a heart rate between 75 and 100 bpm and 3 rotations at heart rates above 100 bpm. Images were reconstructed at 0.5 mm slices with 0.25 mm overlap with an FC03 filter and iterative reconstruction for evaluation at 5% intervals within the 0-95% RR range. CT analysis protocol CT images were reconstructed in the systolic phase using 3mensio Valves Version 7.0 or Version 7.1 (3mensio Medical Imaging BV, Bilthoven, The Netherlands), and Vitrea Software Version (Vital Images, Inc., Minnetonka, MN, USA). The valve leaflets were assessed systematically using both 2D (axial cross-section assessment) and 3D-VR (volume rendered) imaging. The VR images were generated using center-line reconstructions and the hockey puck feature in 3mensio or using front-cut plane or

6 5 thick slab VR functions in Vitrea. In Vitrea, the medium de-noising filter was employed. The window level was adjusted individually for each patient to maximize leaflet visualization and to minimize artefact. The 3D-VR images were generated throughout the cardiac cycle and provided an animated movie of the valve (4D VR-CT), with an emphasis on assessment of systolic leaflet opening. While leaflets with normal motion were difficult to visualize clearly on 4D VR-CT, leaflets with reduced motion were clearly seen in 3D or 4D images. Specifically, motion was defined as normal, mildly reduced (<50% reduction in leaflet opening, relative to the center of the stent frame), moderately reduced (50-70% reduction in leaflet motion), severely reduced (>70% reduction in leaflet motion) and immobile. Quantification of reduced leaflet motion was based on analysis of a volume-rendered en face image of the aortic valve prosthesis at maximal leaflet opening; a measurement was made from the inner margin of the stent frame to the margin of the affected leaflet tip and the distance represented as a percentage of the radius of the stent frame as an orthogonal line through the affected leaflet to the center of the frame. Hypo-attenuating lesions were also studied on maximal intensity projection (MIP) 2D CT and correlated to reduced leaflet motion on 3mensio software with the use of the marker feature and on Vitrea software using the VR auto-alignment with MIP feature. The presence of reduced leaflet motion on 4D VR-CT was compared with independent observations between different CT software (3mensio and Vitrea) by two different groups of specialists (H.J. and J.F./D.B.); in 20 consecutive patients, there was a 100% concordance for assessment of leaflet motion. SAVORY CTs were read by a local site reader (K.K.) and the findings confirmed by the CT core laboratory (H.J.). There was concordance in 61 out of 62 patients included in the SAVORY cohort.

7 6 Pulse duplicator model The Pulse Duplicator system is routinely used to perform hydrodynamic testing on mechanical and bioprosthetic surgical valves as well as transcatheter heart valves under pulsatile conditions, and is functionally representative of the conditions found in the human anatomy. The Pulse Duplicator system consists of a left atrium, mitral valve chamber, pneumatic pulser (power unit), diaphragm pump (left ventricle), aortic valve chamber, capacitance box and mechanical resistance (Figure S6A). The heart rate, cardiac output and mean aortic pressure can be modified to simulate a wide variety of possible flow characteristics that an implanted valve could encounter. Performance measures, including estimated orifice area (EOA), pressure gradients and valve regurgitation, are assessed. The specific analysis performed was a pulse duplicator with a Portico valve of varying size (23 mm, 25 mm, 27 mm or 29 mm) placed in the aortic valve chamber. Hemodynamic settings employed were a heart rate of 70 beats per minute, a cardiac output of 5 Liters/minute and 100 mmhg aortic systolic blood pressure. A leaflet occluder was employed for each prosthesis size to force 0, 1 or 2 leaflets shut (Figure S6B). Mean pressure drop (ie. pressure gradient) was measured for each scenario and is shown in Table S5. For all prosthesis sizes, forcing only 1 leaflet shut permitted acceptable EOAs over 1.5 cm 2 with mean gradients below 10 mmhg in all cases. Forcing 2 leaflets shut impacted on gradients (> 20 mmhg) in mm prostheses but a gradient of the order of 15 mmhg and an EOA of 1.35 cm 2 was still obtained with the largest 29 mm prosthesis.

8 7 Figure S1: CT appearance of bioprosthetic aortic valves with normal and reduced leaflet motion (A-D, appendix video 2A) Normal appearance of PORTICO transcatheter aortic valve: 2D axial (A), longitudinal (B) and volume-rendered cross-sectional views showing mobile leaflets in systole (C) and diastole (D). Normal leaflets are only visible on CT in diastole, at their line of coaptation in axial images. (E-H, appendix video 2B): PORTICO valve with hypoattenuating lesions on the leaflet suggestive of thrombus and impaired leaflet mobility (arrow): 2D axial (E) and longitudinal (F) views. The hypoattenuating lesions always involve the base of the leaflet and extend to the center of the frame. Volume-rendered views showing abnormal leaflets visible as wedge-shaped or semilunar opacities in both systole (G) and diastole (H).

9 8 Figure S2: Correlation of transesophageal echocardiogram (TEE) with computed tomography (CT) for the assessment of reduced leaflet motion in a patient with a Portico valve. (A-B, Appendix video 3A) Transesophageal echocardiogram showing reduced leaflet motion (solid arrow) in the long-axis (A) and short-axis (B) views. (C-D, Appendix videos 3B and 3C) Corresponding 2D CT views of the long-axis and short-axis showing valve leaflet with hypoattenuating lesions (dashed arrow). (E-F, Appendix videos 3D and 3E) Corresponding volume-rendered computed tomography (CT) views of the long-axis and short-axis showing reduced leaflet motion in systole (dashed arrow). The hypoattenuating lesions always involve the base of the leaflet and extend to the center of the frame. Volume rendered views showing abnormal leaflets visible as wedge-shaped or semilunar opacities in both systole and diastole. A specific echocardiographic pattern that corresponds to the CT findings in both distribution of leaflet involvement and morphology is observed on TEE for all leaflets with abnormal mobility: a hyperechogenic, homogeneous mass, over-imposed and coating the aortic surface of the otherwise intact leaflets, with a clearly delineated contour. These echogenic structures are seen to be the most prominent in the periphery (adjacent to the stent), tapering into the body and edges of the leaflet. These echogenic masses were always on the aortic (outlet) surface of the valves and resulted in reduced mobility of the affected leaflets.

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11 10 Figure S3: Mean aortic valve gradients in patients with and without reduced leaflet motion in the PORTICO IDE cohort. No significant differences between patients with and without reduced leaflet motion at discharge, 30 days and 6 months.

12 11 Figure S4: Resolution of reduced leaflet motion of Sapien XT valve with anticoagulation. (A-F) Long-axis and short-axis views showing evidence of reduced leaflet motion on transesophageal echocardiogram (A-B), 2D CT (C-D) and volume rendered CT (E-F, Appendix video 4A and 4B). Long-axis and short-axis views on 2D CT (G-H) and volume rendered CT (I- J, Appendix video 4C and 4D) confirming resolution of hypoattenuating opacities suggestive of thrombus and restoration of normal leaflet motion with anticoagulation.

13 12 Figure S5: Case example of resolution of hypoattenuating opacities and restoration of leaflet motion in Sapien XT with warfarin and reappearance of thrombus on a different leaflet on follow-up CT after discontinuation of warfarin. Transesophageal echocardiographic (A-B) and cross-sectional computed tomography (CT) (C-D) performed 30 days after transcatheter aortic valve replacement showing hypoattenuating lesions and reduced leaflet motion of the Sapien-XT leaflet between the left and non-coronary cusps. The patient was started on anticoagulation with warfarin, which was continued for 3 months and then discontinued. Follow-up CT scan done 3 months after discontinuation of warfarin showed resolution of hypoattenuating opacities on the previously involved leaflet (solid arrow) and reappearance on a different leaflet (dashed arrow) (E-F).

14 13 Figure S6: Pulse duplicator model (A) Pulse duplicator setup (B) The leaflet occluder model used to force 0, 1 or 2 leaflets shut

15 14 Table S1: Computed tomography and echocardiographic findings in the PORTICO IDE cohort* Normal leaflet motion Reduced leaflet motion p-value N=33 N=22 Baseline CT Annulus perimeter mm 75.8 ± ± Annulus area mm ± ± Aortic root angulation 46.7 ± ± Annulus eccentricity (minor/major) 0.8 ± ± AV calcification volume (mm 3 ) ± ± Post-TAVR CT Stent mean depth mm 4.2 ± ± Mean strut separation mm 5.0 ± ± Strut eccentricity (max-min) - mm 3.7 ± ± Stent dimensions at the level of inflow Stent eccentricity (minor/major) 0.8 ± ± Perimeter mm 75.9 ± ± Area mm ± ± Stent dimensions at the level of sinus of Valsalva Stent eccentricity (minor/major) 0.9 ± ±

16 15 Perimeter mm 77.7 ± ± Area- mm ± ± Baseline TTE Ejection fraction - % 55.0 ± ± Mean AV gradient - mm Hg 42.6 ± ± Stroke volume ml 64.7 ± ± Cardiac output - L/min 4.5 ± ± Discharge TTE Ejection fraction - % 54.8 ± ± Mean AV gradient - mm Hg 9.5 ± ± day TTE Ejection fraction - % 53.7 ± ± 11.7 >0.99 Mean AV gradient - mm Hg 9.0 ± ± month TTE Ejection fraction - % 62.6 ± ± Mean AV gradient - mm Hg 9.5 ± ± * Plus minus values are means ±SD. Two sample t-test or Wilcoxon rank-sum test for between-group comparisons. CT denotes computed tomography, AV aortic valve, TAVR transcatheter aortic valve replacement, TTE transthoracic echocardiography. From contrast scans with 850 Hounsfield Unit threshold of detection.

17 16 Table S2: Antiplatelet and antithrombotic medications at the time of CT scan* Normal leaflet motion Reduced leaflet motion p-value PORTICO IDE Therapeutic warfarin vs. NOACs vs. No/subtherapeutic warfarin N=32 N= Therapeutic warfarin - no./total no. (%) 8 (25.0) 0 (0) NOAC - no./total no. (%) 4 (12.5) 1 (4.5) No/subtherapeutic anticoagulation - no./total no. (%) 20 (62.5) 21 (95.5) Therapeutic warfarin vs. No/subtherapeutic warfarin N=28 N= No/subtherapeutic anticoagulation - no./total no. (%) 20 (71.4) 21 (100.0) Therapeutic warfarin - no./total no. (%) 8 (28.6) 0 (0) Therapeutic warfarin vs. DAPT N=17 N= DAPT - no./total no. (%) 9 (52.9) 11 (100.0) Therapeutic warfarin - no./total no. (%) 8 (47.1) 0 (0) Aspirin vs. Clopidogrel (Single antiplatelet therapy) N=19 N= Aspirin alone - no./total no. (%) 13 (68.4) 8 (80.0) Clopidogrel alone - no./total no. (%) 6 (31.6) 2 (20.0)

18 17 Registries Therapeutic warfarin vs. NOACs vs. No/subtherapeutic warfarin N=114 N= Therapeutic warfarin - no./total no. (%) 13 (11.4) 0 (0) NOAC - no./total no. (%) 13 (11.4) 2 (11.8) No/subtherapeutic anticoagulation - no./total no. (%) 88 (77.2) 15 (88.2) Therapeutic warfarin vs. No/subtherapeutic warfarin N=101 N= No/subtherapeutic anticoagulation - no./total no. (%) 88 (87.1) 15 (100.0) Therapeutic warfarin - no./total no. (%) 13 (12.9) 0 (0) Therapeutic warfarin vs. DAPT N=38 N= Therapeutic warfarin - no./total no. (%) 13 (34.2) 0 (0) DAPT no./total no. (%) 25 (65.8) 10 (100.0) Aspirin vs. Clopidogrel (Single antiplatelet therapy) N=67 N=5 >0.99 Aspirin alone - no./total no. (%) 52 (77.6) 4 (80.0) Clopidogrel alone - no./total no. (%) 15 (22.4) 1 (20.0) * Fisher s exact test was used for between-group comparisons.

19 18 Table S3: Echocardiographic and computed tomography characteristics of pooled registries* Normal leaflet motion Reduced leaflet motion P-value N=115 N=17 Baseline Echocardiographic Parameters Mean AV gradient (mmhg) 46.6 ± ± Left ventricular ejection fraction (%) 55.3 ± ± Stroke volume (ml) 66.0 ± ± Cardiac output (L/min) 4.4 ± ± days echocardiographic parameters Left ventricular ejection fraction (%) 55.9 ± ± Mean AV gradient (mmhg) 9.3 ± ± Peak AV gradient (mmhg) 18.2 ± ± CT findings Valve implant depth: all valves (mm) 3.2 ± ± * Plus minus values are means ±SD. Two sample t-test or Wilcoxon rank-sum test for between-group comparisons. AV denotes aortic valve, CT computed tomography.

20 19 Table S4: Frequency of reduced leaflet motion in different valve types in the registries Frequency N=17 PORTICO IDE- no. (%) 5/15 (33.3) Edwards- no. (%) 7/58 (12.1) Edwards-SAPIEN- no. (%) 1/6 (16.6) SAPIEN XT- no. (%) 4/42 (9.5) Sapien-3- no. (%) 2/10 (20.0) CoreValve- no. (%) 2/24 (8.3) Lotus valve- no. (%) 1/8 (12.5) Surgical valves no. (%) 2/27 (7.4) Edwards Perimount 1/11 (9.1) Perimount Magna 1/9 (11.1) Trifecta 0/3 (0) Mitroflow 0/1 (0) Perceval 0/2 (0)

21 20 Table S5: Pulse duplicator model to evaluate the effect of leaflet motion on valve gradients Valve Size (mm) Leaflet(s) Forced Closed Mean Pressure Gradient (mmhg) Effective orifice area (cm 2 )

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