J A C C : C A R D I O V A S C U L A R I N T E R V E N T I O N S V O L . 1 1 , N O . 1 6 , 2 0 1 8 LettersA U G U S T 2 7 , 2 0 1 8 : 1 6 5 8 – 6 7

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2.6-fold greater in patients undergoing stagedprocedures, which was confirmed in a propensitymatched analysis (5). This highlights the importanceof adequate data collection and timely assessment ofrenal function after multistage PCI.

Ernest Spitzer, MDEugene McFadden, MDYoshinobu Onuma, MD, PhD*Patrick W. Serruys, MD, PhD

*International Centre for Circulatory HealthNational Heart and Lung InstituteImperial College London59 North Wharf RoadLondon W2 1LAUnited KingdomE-mail: patrick.w.j.c.serruys@gmail.comhttps://doi.org/10.1016/j.jcin.2018.06.046

© 2018 Published by Elsevier on behalf of the American College of CardiologyFoundation.

Please note: Prof. Serruys has served as a consultant to Abbott, AstraZeneca,Biotronik, Cardialysis, GLG Research, Medtronic, Sinomedical, Société EuropaDigital & Publishing, Stentys, Svelte, Phillips/Volcano, St. Jude Medical, Qual-imed, and Xeltis. Dr. Onuma is a member of the advisory board for AbbottVascular. The other authors have reported that they have no relationshipsrelevant to the contents of this paper to disclose.

RE F E RENCE S

1. Spitzer E, McFadden E, Vranckx P, et al. Defining staged procedures forpercutaneous coronary intervention trials: a guidance document. J Am CollCardiol Intv 2018;11:823–32.

2. Giacoppo D, Madhavan MV, Baber U, et al. impact of contrast-induced acutekidney injury after percutaneous coronary intervention on short- and long-term outcomes: pooled analysis from the HORIZONS-AMI and ACUITY trials.Circ Cardiovasc Interv 2015;8:e002475.

3. Farooq V, van Klaveren D, Steyerberg EW, et al. Anatomical and clinicalcharacteristics to guide decision making between coronary artery bypasssurgery and percutaneous coronary intervention for individual patients:development and validation of SYNTAX score II. Lancet 2013;381:639–50.

4. Weisbord SD, Gallagher M, Jneid H, et al. Outcomes after angiography withsodium bicarbonate and acetylcysteine. N Engl J Med 2018;378:603–14.

5. Shah M, Gajanana D, Wheeler DS, et al. Effects of staged versus ad hocpercutaneous coronary interventions on renal function-Is there a benefit tostaging? Cardiovasc Revasc Med 2017;18:344–8.

RESEARCH CORRESPONDENCE

“Cusp-Overlap”View SimplifiesFluoroscopy-GuidedImplantation ofSelf-Expanding Valve inTranscatheter AorticValve Replacement

Accurate device implantation in transcatheter aorticvalve replacement (TAVR) depends on: 1) obtaining a

3-cusp coplanar projection; and 2) centering deliverycatheter across the valve. Unlike balloon-expandablevalves, which require a coplanar projection with 3cusps (yellow dot ¼ non [N], green ¼ right [R],red ¼ left [L]) (1) (Figure 1A), additional steps are takenwhen implanting a self-expanding valve, for example,CoreValve/Evolut R (Medtronic, Minneapolis,Minnesota). First, parallax of the delivery catheter(yellow arrow) should be eliminated, requiring amore caudal/cranial and not coplanar view(Figure 1B). Second, the delivery catheter is naturallypositioned toward the outer curvature of the aorticroot (red arrow) (Figure 1B). Third, annular contactoccurs from the non-coronary cusp (NCC) to the leftcoronary cusp (LCC) (Figures 1C and 1D), with thedotted blue arrow indicating direction andapproximate distance for the valve frame to anchor(Figure 1D).

A coplanar projection by overlapping the rightcoronary cusp (RCC) and LCC (cusp-overlap view)offers several potential advantages in CoreValve/Evolut R deployment (Figures 1E to 1T):

1. Elimination of parallax of the delivery catheter,2. Delivery catheter more centered across aortic

valve,3. Deployment in true coplanar view,4. Shorter visual distance for CoreValve/Evolut R to

engage the NCC and LCC, and5. En-face view of NCC enables higher valve implan-

tation without device “pop-out” upon release,especially in a large annulus with minimaloversizing.

This concept is illustrated in a sample multi-detector computed tomography (MDCT) analysis us-ing 3Mensio Valves software (Pie Medical Imaging,Maastricht, the Netherlands). Standard 3-cusp view ofleft anterior oblique (LAO) 8�, caudal 3� is viewed byan operator at the position of the solid white arrow,projecting more along the annular long axis(Figure 1E). Natural positioning of the CoreValvedelivery catheter (blue circle) between the NCC(yellow dot) and the RCC (green dot) (Figures 1F and1G) requires the valve frame to engage the LCC (reddot) in the direction of the solid blue arrow.However, under fluoroscopy, the perceived valveframe flowering would actually be in the directionand distance of the dotted blue arrow (Figures 1Fand 1G), depicted in Figure 1H. A coplanar projectionof the same patient using the cusp-overlap view, inthis case, right anterior oblique (RAO) 13�, caudal30�, overlaps the RCC and LCC, and displays theannulus more toward the short axis (Figure 1I). The

FIGURE 1 Cusp-Overlap View in TAVR With Self-Expanding Valve

CoreValve deployment using 3-cusp coplanar view (A to D). Understanding the 3-cusp and cusp-overlap views in CoreValve deployment using computed tomography

(E–L). CoreValve deployment using the cusp-overlap view (L to T). Detailed explanations are stated in the text. CAU ¼ caudal; L ¼ left coronary cusp; LAO ¼ left

anterior oblique; LCC ¼ left coronary cusp; N ¼ non-coronary cusp; NCC ¼ non-coronary cusp; R ¼ right coronary cusp; RAO ¼ right anterior oblique; RCC ¼ right

coronary cusp; TAVR ¼ transcatheter aortic valve replacement.

Letters J A C C : C A R D I O V A S C U L A R I N T E R V E N T I O N S V O L . 1 1 , N O . 1 6 , 2 0 1 8

A U G U S T 2 7 , 2 0 1 8 : 1 6 5 8 – 6 7

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J A C C : C A R D I O V A S C U L A R I N T E R V E N T I O N S V O L . 1 1 , N O . 1 6 , 2 0 1 8 LettersA U G U S T 2 7 , 2 0 1 8 : 1 6 5 8 – 6 7

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delivery catheter appears more centered (Figure 1J),and perceived distance (dotted blue arrow) of thevalve frame flowering from the NCC to the LCC isreduced (Figures 1J and 1K), as depicted in Figure 1L.

Figure 1M shows the initial MDCT-derived 3-cuspview confirmed by 2 pigtail catheters withoutintravenous contrast, followed by placing them atthe RCC and LCC, respectively, to achieve the cusp-overlap view (Figure 1N). Initial device positioning atRAO 13�, caudal 30� shows no parallax of a morecentered delivery catheter (yellow arrow)(Figure 1O). The NCC nadir is better visualized(Figure 1P), allowing a higher valve deployment witha lower risk of “pop-out.” Annular contact from theNCC to the LCC occurs over a shorter distance(dotted blue arrow) during valve flowering anddeployment (Figures 1Q and 1R). Completionaortograms at projections coaxial to the CoreValveshow that inflow (dotted white arrows) and waistdiameters appear smaller in the Cusp-Overlap(Figure 1S) than in the coplanar view (Figure 1T),consistent with perceived differences due to axisorientation of the annulus on MDCT.

A dedicated software or MDCT is not necessary toidentify the cusp-overlap view, because it can beaccomplished fluoroscopically by placing a pigtailcatheter in the RCC and either an angled pigtail, 0.035-inch J wire, or 0.018-inch pre-shaped soft nitinol wirein the LCC. Rotating the C-arm to superimpose bothcatheters (or wire) enables overlapping of the RCC andthe LCC, generating the cusp-overlap view (Figure 1N).Our technique also does not require a third arterialpuncture. The pigtail or guidewire is removed fromthe valve access site after the angle has beendetermined. Although the 2-pigtail technique hasbeen used in TAVR with pure aortic insufficiency,here we report using a similar technique to determinethe novel cusp-overlap view to facilitate TAVR withthe CoreValve.

In patients with challenging body habitus, such asobesity, an RAO, caudal view may reduce fluoro-scopic image quality, and certain extreme RAO,caudal angles may not be possible to create the cusp-overlap view. In those instances, we perform Cor-eValve TAVR using a 3-cusp view or overlapping theNCC and the RCC in an LAO, cranial view. Whenoverlapping 2 cusps, it is essential to place the 2pigtails or a pigtail and a wire in the overlappingcusps, respectively, to ensure they are coplanar. Webelieve this rule may simplify implantation of certainself-expanding valves, such as the Evolut R Cor-eValve and Portico (Abbott Structural Heart, SantaClara, California).

*Gilbert H.L. Tang, MD, MSc, MBASyed Zaid, MDIassen Michev, MDHasan Ahmad, MDRyan Kaple, MDCenap Undemir, MDMartin Cohen, MDSteven L. Lansman, MD, PhD

*Structural Heart ProgramMount Sinai Health SystemIcahn School of Medicine at Mount Sinai1190 Fifth Avenue, GP2W, Box 1028New York, New York 10029E-mail: gilbert.tang@mountsinai.orghttps://doi.org/10.1016/j.jcin.2018.03.018

� 2018 by the American College of Cardiology Foundation. Published by Elsevier.

Please note: This study was previously presented at the following annualmeetings: PCR London Valves in 2015, TCT in 2016, and ACC in 2017. Dr. Tanghas been a physician proctor for Edwards Lifesciences and Medtronic. All otherauthors have reported that they have no relationships relevant to the contents ofthis paper to disclose.

RE F ER ENCE

1. Kasel AM, Cassese S, Leber AW, von Scheidt W, Kastrati A. Fluoros-copy-guided aortic root imaging for TAVR. J Am Coll Cardiol Img 2013;6:274–5.

RESEARCH CORRESPONDENCE

High-Sensitivity CardiacTroponin T LevelsIdentify Patients WithNon–ST-SegmentElevation AcuteCoronary SyndromeWho Benefit FromInvasive Assessment

Cardiac troponin (cTn) levels are commonly used as aclue whether or not to initiate beneficial treatmentsin patients with non–ST-segment elevation acutecoronary syndrome (NSTE-ACS). The current view isthat patients with cTn elevation should undergoinvasive assessment aiming at coronary revasculari-zation. This notion, however, is based on data fromolder studies using less sensitive cTn assays andpartly high cutoffs (1,2).

Newer high-sensitivity (hs) cTn assays allow for themeasurement of minute amounts of circulating cTnand are increasingly used in clinical practice. It iscurrently not clear whether there might be a hs-cTn