Feasibility and outcomes of combined transcatheter aortic valve replacement with other structural heart interventions in a single session: a matched cohort study Ahmed A Khattab, 1 Steffen Gloekler, 1 Beate Sprecher, 1 Samera Shakir, 1 Ênio Guerios, 2 Stefan Stortecky, 1 Crochan J O’Sullivan, 1 Fabian Nietlispach, 3 Aris Moschovitis, 1 Thomas Pilgrim, 1 Lutz Buellesfeld, 1 Peter Wenaweser, 1 Stephan Windecker, 1 Bernhard Meier 1 To cite: Khattab AA, Gloekler S, Sprecher B, et al. Feasibility and outcomes of combined transcatheter aortic valve replacement with other structural heart interventions in a single session: a matched cohort study. Open Heart 2014;1:e000014. doi:10.1136/openhrt-2013- 000014 AAK and SG contributed equally. Received 5 December 2013 Revised 8 May 2014 Accepted 28 May 2014 1 Cardiology, Cardiovascular Department, Bern University Hospital, Bern, Switzerland 2 Centro de Cardiopatias Congênitas e Estruturais do Paraná, Curitiba, Paraná, Brazil 3 Department of Cardiology, Zurich University Hospital, Zürich, Switzerland Correspondence to Professor Bernhard Meier; [email protected]ABSTRACT Background: Concurrent cardiac diseases are frequent among elderly patients and invite simultaneous treatment to ensure an overall favourable patient outcome. Aim: To investigate the feasibility of combined single- session percutaneous cardiac interventions in the era of transcatheter aortic valve implantation (TAVI). Methods: This prospective, case–control study included 10 consecutive patients treated with TAVI, left atrial appendage occlusion and percutaneous coronary interventions. Some in addition had patent foramen ovale or atrial septal defect closure in the same session. The patients were matched in a 1:10 manner with TAVI-only cases treated within the same time period at the same institution regarding their baseline factors. The outcome was validated according to the Valve Academic Research Consortium (VARC) criteria. Results: Procedural time (126±42 vs 83±40 min, p=0.0016), radiation time (34±8 vs 22±12 min, p=0.0001) and contrast dye (397±89 vs 250±105 mL, p<0.0001) were higher in the combined intervention group than in the TAVI-only group. Despite these drawbacks, no difference in the VARC endpoints was evident during the in-hospital period and after 30 days (VARC combined safetyendpoint 32% for TAVI only and 20% for combined intervention, p=1.0). Conclusions: Transcatheter treatment of combined cardiac diseases is feasible even in a single session in a high-volume centre with experienced operators. INTRODUCTION Percutaneous cardiac interventions, by their less invasive nature, enhance patient comfort, accelerate recovery time and shorten hospitalisation duration. They have proven to be a valid alternative to open heart surgery for different patient and disease subsets. This becomes particularly true among patients with coexisting cardiac dis- eases necessitating complex combined surgi- cal management which puts them at an additional operative risk. 1 2 With the intro- duction of transcatheter aortic valve implant- ation (TAVI), a long neglected population of surgically high-risk and inoperable patients gained access to effective treatment for aortic valve stenosis. 3 Frequently, however, these elderly patients have concurrent coronary artery disease and/or atrial fibrillation, which are both associated with an independ- ent adverse prognosis. 4–6 The management of these patients should therefore cover con- current heart diseases to ensure an overall favourable outcome after TAVI. 7 Staged or simultaneous percutaneous coronary inter- ventions (PCI) and TAVI have been shown to be safe and feasible in different series. 89 We recently described a successful first case of simultaneous TAVI, PCI and percutaneous device closure of the left atrial appendage (LAA). 10 LAA occlusion has been demon- strated to be at least equally effective to long- term warfarin therapy in preventing systemic embolism among atrial fibrillation patients 11 and is commonly used as a substitute for anticoagulation among selected patients not suitable for chronic anticoagulation. 12 On the other hand, patent foramen ovale (PFO) and atrial septal defects (ASD) are a docu- mented source for systemic emboli 13 and their percutaneous closure is feasible and effective in reducing paradoxical embol- ism. 14–17 We sought to investigate the feasibil- ity of simultaneous cardiac interventions Khattab AA, Gloekler S, Sprecher B, et al. Open Heart 2014;1:e000014. doi:10.1136/openhrt-2013-000014 1 Aortic and vascular disease source: https://doi.org/10.7892/boris.62541 | downloaded: 14.6.2020
Transcript
Feasibility and outcomes of combinedtranscatheter aortic valve replacementwith other structural heart interventionsin a single session: a matchedcohort study
Ahmed A Khattab,1 Steffen Gloekler,1 Beate Sprecher,1 Samera Shakir,1
Ênio Guerios,2 Stefan Stortecky,1 Crochan J O’Sullivan,1 Fabian Nietlispach,3
Aris Moschovitis,1 Thomas Pilgrim,1 Lutz Buellesfeld,1 Peter Wenaweser,1
Stephan Windecker,1 Bernhard Meier1
To cite: Khattab AA,Gloekler S, Sprecher B, et al.Feasibility and outcomes ofcombined transcatheter aorticvalve replacement with otherstructural heart interventionsin a single session: amatchedcohort study. Open Heart2014;1:e000014.doi:10.1136/openhrt-2013-000014
AAK and SG contributedequally.
Received 5 December 2013Revised 8 May 2014Accepted 28 May 2014
1Cardiology, CardiovascularDepartment, Bern UniversityHospital, Bern, Switzerland2Centro de CardiopatiasCongênitas e Estruturais doParaná, Curitiba, Paraná,Brazil3Department of Cardiology,Zurich University Hospital,Zürich, Switzerland
ABSTRACTBackground: Concurrent cardiac diseases are frequentamong elderly patients and invite simultaneoustreatment to ensure an overall favourable patientoutcome.Aim: To investigate the feasibility of combined single-session percutaneous cardiac interventions in the eraof transcatheter aortic valve implantation (TAVI).Methods: This prospective, case–control studyincluded 10 consecutive patients treated with TAVI, leftatrial appendage occlusion and percutaneous coronaryinterventions. Some in addition had patent foramenovale or atrial septal defect closure in the samesession. The patients were matched in a 1:10 mannerwith TAVI-only cases treated within the same timeperiod at the same institution regarding their baselinefactors. The outcome was validated according to theValve Academic Research Consortium (VARC) criteria.Results: Procedural time (126±42 vs 83±40 min,p=0.0016), radiation time (34±8 vs 22±12 min,p=0.0001) and contrast dye (397±89 vs 250±105 mL,p<0.0001) were higher in the combined interventiongroup than in the TAVI-only group. Despite thesedrawbacks, no difference in the VARC endpoints wasevident during the in-hospital period and after 30 days(VARC combined safety endpoint 32% for TAVI onlyand 20% for combined intervention, p=1.0).Conclusions: Transcatheter treatment of combinedcardiac diseases is feasible even in a single session ina high-volume centre with experienced operators.
INTRODUCTIONPercutaneous cardiac interventions, by theirless invasive nature, enhance patientcomfort, accelerate recovery time andshorten hospitalisation duration. They haveproven to be a valid alternative to open heart
surgery for different patient and diseasesubsets. This becomes particularly trueamong patients with coexisting cardiac dis-eases necessitating complex combined surgi-cal management which puts them at anadditional operative risk.1 2 With the intro-duction of transcatheter aortic valve implant-ation (TAVI), a long neglected population ofsurgically high-risk and inoperable patientsgained access to effective treatment for aorticvalve stenosis.3 Frequently, however, theseelderly patients have concurrent coronaryartery disease and/or atrial fibrillation,which are both associated with an independ-ent adverse prognosis.4–6 The managementof these patients should therefore cover con-current heart diseases to ensure an overallfavourable outcome after TAVI.7 Staged orsimultaneous percutaneous coronary inter-ventions (PCI) and TAVI have been shown tobe safe and feasible in different series.8 9 Werecently described a successful first case ofsimultaneous TAVI, PCI and percutaneousdevice closure of the left atrial appendage(LAA).10 LAA occlusion has been demon-strated to be at least equally effective to long-term warfarin therapy in preventing systemicembolism among atrial fibrillation patients11
and is commonly used as a substitute foranticoagulation among selected patients notsuitable for chronic anticoagulation.12 Onthe other hand, patent foramen ovale (PFO)and atrial septal defects (ASD) are a docu-mented source for systemic emboli13 andtheir percutaneous closure is feasible andeffective in reducing paradoxical embol-ism.14–17 We sought to investigate the feasibil-ity of simultaneous cardiac interventions
Khattab AA, Gloekler S, Sprecher B, et al. Open Heart 2014;1:e000014. doi:10.1136/openhrt-2013-000014 1
including TAVI, PCI and LAA occlusion with or withoutPFO/ASD closure in an elderly comorbid population.
METHODSPatient population and justification of combinedproceduresTen consecutive cases were selected from a cohort of400 patients with severe aortic stenosis allocated to TAVIby the decision of the heart team at the SwissCardiovascular Center of the Bern University Hospitalbetween 2009 and 2012. Data were entered into a pro-spective registry and analysed according to the criteriaof the Valve Academic Research Consortium (VARC).18
Patient characteristics were compared with a pool of 100case–control patients to match every patient with a com-bined intervention to a control according to the Societyof Thoracic Surgeons (STS) score. Given the prospectivecohort study character, there were no formal exclusioncriteria. The Bern TAVI registry is part of the Swiss TAVIregistry and has been approved by the local and nationalethics committees. The Bern registry for LAA occlusionis also approved by the local ethics committee. For eachof the combined interventions, dedicated forms listingpotential adverse events, that is, the risk of the respectiveprocedure, were provided. With regard to the risk/benefit ratio of combined versus staged interventionsand especially under the aspect of avoiding several
hospitalisations and general anaesthesia, the combinedapproach was deemed patient friendly without increas-ing complications and therefore recommended to theselected patients of this study.
Data acquisitionDemographic and clinical characteristics, proceduraldata, adverse events and outcome data of in-hospital andfollow-up periods were systematically collected. After 1and 3–4 months, a standardised follow-up examinationwas performed. After 3–4 months, in addition to clinicaland neurological examination, a transesophageal echo-cardiography (TEE) was performed to ensure correctseating and freedom of relevant thrombi of the LAAclosure device. All events underwent adjudication by ateam of an independent cardiac surgeon and an inde-pendent interventional cardiologist. Outcome isreported according to the VARC criteria.
Combined interventionsBeforehand, coronary angiography with invasive haemo-dynamic assessment, CT angiography (CTA) and TEEfor aortic root assessment and exclusion of LAA thrombiwere performed. Three of the 10 cases were transmittedlive to international interventional courses. If indicatedby angiographic stenosis degree, PCI was performed firstby transfemoral access with 5 or 6 Fr guiding cathetersand exclusively using drug-eluting stents (DES), whichwas the case in 6 of the 10 combined patients. Two didnot suffer from CAD and in two, the CAD was treatedearlier in a separate procedure. Next, TAVI was per-formed under mild sedoanalgaesia and inguinal localanaesthesia only via transfemoral access. A single orboth femoral arteries were accessed and a suture-basedvascular closure device preinstalled on the respectiveside of access for TAVI. Aortic stenosis was crossed usingan Amplatzer left diagnostic catheter and a straighttipped wire. Via a stiff wire, balloon aortic valvuloplastyunder rapid pacing (180/min) was performed. Afteradvancement of a 16–20 F femoral sheath, the EdwardsSapien bioprosthesis (balloon-expandable titaniumframe containing bovine pericardial leaflets) orMedtronic Corevalve bioprosthesis (self-expandablenitinol frame containing porcine pericardial leaflets insupra-annular position) was deployed. Selection of thedevice size was based on previous aortic root assessmentby TEE, CTA or angiography. After TAVI, LAA exclusionand septal closure procedures followed on. In all casesthe first generation Amplatzer Cardiac Plug (ACP) wasused. Similar to TAVI, LAA occlusion was performed in a
Figure 1 Representative course
of action in case 2.
Figure 2 End result in case 2.
2 Khattab AA, Gloekler S, Sprecher B, et al. Open Heart 2014;1:e000014. doi:10.1136/openhrt-2013-000014
Open Heart
frugal manner without general anaesthesia or TEE guid-ance, that is, under fluoroscopy only: after accessing theleft atrium through a trans-septal puncture or passagethrough a pre-existing PFO or ASD, the device size wasselected based on biplane angiography of the LAAthrough the 9–13 F delivery sheath. After deployment,sustained tugging with the delivery cable tested ACPseating within the LAA and another biplane left atrialangiography was performed prior to the release. In caseof unsatisfactory positioning or anchoring, the plug wasrecaptured and redeployed in a different angle orchanged for a more suitable sized device. On the wayback, a pre-existing PFO or ASD was closed by the samecable and delivery sheath using Amplatzer PFO or ASD
occluders. After closure of the percutaneous arterialaccess and slight compression of the femoral vein,patients were posthydrated with normal saline accordingto the standard protocol and transferred to a cardiacintermediate care ward (see figures 1 and 2 for a repre-sentative course of action in case 2). Restart of oralanticoagulation was omitted. A dose of 75 mg of clopido-grel daily for 3–6 months and 100 mg of acetylsalicylicacid were prescribed indefinitely. For documentation ofaortic bioprosthesis performance and exclusion ofdevice displacement or pericardial effusion, transthor-acic echocardiography was performed on day one afterintervention and after 30 days. The patients were dis-charged on postprocedure days 3–7.
Table 1
Individual case description
(1) 78-year-old man AS, CAD, AFib Rationale: high risk of bleeding/avoidance of triple therapy
Khattab AA, Gloekler S, Sprecher B, et al. Open Heart 2014;1:e000014. doi:10.1136/openhrt-2013-000014 3
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Matching and statistical analysisFor every combined case, 10 controls were selected fromthe database according to the most fitting STS score.Since the STS score contains all relevant patientcharacteristics and has been shown to be very accuratein predicting a 30-day outcome also in TAVI patients, itwas deemed appropriate for matching. Continuous vari-ables are presented as mean±SD and were comparedusing the unpaired Mann-Whitney U test. Categoricaldata are expressed as frequency (percentages) and werecompared with Fisher’s exact test. All tests and CIs aretwo-sided, and an α level of 0.05 was chosen to deter-mine the statistical significance of differences. Analyseswere performed using GraphPad Prism 6 (http://www.graphpad.com).
RESULTSBaseline characteristics and matchingTable 1 provides a brief description of each individualcase and baseline characteristics are summarised intable 2. The rationale for LAA occlusion along with
TAVI (5 with CoreValve, 5 with Edwards Sapien XT) andPCI were high bleeding risk in six and prior majorbleeding in four patients. In 3 of the 10 patients, PFOclosure (2) and ASD closure (1) were performed in add-ition. Matching could be performed with an excellentagreement (mean difference in STS score between casesand control groups: 0.37±1.01).
Periprocedural and 1-month follow-upExpectedly, procedure time, use of contrast and radi-ation was higher in the combined group when com-pared with the controls with TAVI only. Despite thesedrawbacks, no difference in the VARC endpoints wasevident during the in-hospital period and after 30 days(see tables 3 and 4).
Three-month follow-upTable 5 illustrates the 3–4 months clinical and echocar-diographic follow-up data. No patient was lost tofollow-up. All patients but one (sudden cardiac death118 days after the index procedure) were alive without
Table 2
Baseline characteristics TAVI matched cases (n=100) Combined interventions (n=10) p Value
events. Aortic bioprosthesis function was normal in allpatients with no or mild paraprosthetic aortic regurgita-tion. No residual shunts or thrombi were seen afterLAAO or PFO/ASD closure.
DISCUSSIONSurgical aortic valve replacement is associated with anunadjusted operative mortality of 3% and reaches 5%when combined with CABG. The surgical mortality rate
Table 4
1-Month follow-up (VARC endpoints) TAVI matched cases (n=100) Combined interventions (n=10) p Value
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rises exponentially in patients above 80 years.19 Rates ofthromboembolic complications (related to atrial fibrilla-tion and paradoxical embolism) as well as spontaneousand iatrogenic bleeding tendency increase with advan-cing age as reflected in contemporary risk stratificationsystems. Octogenarians are reluctant to seek medicalcare and physicians are hesitant to apply appropriatetherapeutic strategies. With the introduction of variouscatheter-based percutaneous structural heart diseaseinterventions, this hitherto neglected morbid populationgains access to guideline-based medical care.In our series, all patients had severe aortic stenosis
(which was treated by TAVI) and eight of them had sig-nificant coronary artery disease (of whom six weretreated with DES along with TAVI). Regarding the timepoint of treating concomitant CAD, this should betreated at one time with the respective procedure ofaortic valve replacement, irrespective of the approachselected by the heart team beforehand (ie, surgicalrevascularisation and SAVR or PCI and TAVI).On top of that they had atrial fibrillation, which would
have required chronic anticoagulation (CHADS2 scorefor all patients >1) in addition to dual antiplatelettherapy recommended for coronary stents for at least3–6 months. Although newer data suggest safety and effi-cacy of a combination of clopidogrel and oral anticoagu-lation, many patients still receive triple oralantithrombotic therapy, which carries a significantlyhigher risk of bleeding than dual antiplatelet therapy20 21
while dual antiplatelet therapy alone is less effective thanoral anticoagulation in preventing thromboembolic com-plications.22 LAA closure provides stroke preventionequal to that of warfarin without bleeding risk.11
Although the value of PFO/ASD closure as a primary pre-vention measure against paradoxical embolism is notclear, we performed this as the final step of the combinedinterventions among these patients because of thegeneral ease of this intervention in the setting of LAAclosure, with the appropriate gear already in place.Compared with their matched counterparts receiving
TAVI only, the combined intervention cases sufferedfrom a higher burden of comorbidities and their proce-dures were longer and consumed more contrast dye. Inspite of these disadvantages, the immediate andintermediate-term outcomes were not different betweengroups as judged by the VARC criteria. Alternatively tothis single session approach a staged approach mayreduce dye usage per session and hence transient kidneyinjury is occasionally encountered. However, this occursat the expense of reduced patient comfort and compli-ance, which may lead to refraining from planned com-plementary interventions. Obviously, the power of thepresent study is too low to address the safety of increasedcontrast use. The combined procedures were all per-formed without general anaesthesia and without TEEguidance. Combining therapeutic measures becomeseven more compelling if general anaesthesia and TEEguidance are deemed necessary.
LimitationsThe present study has several limitations: first, the pre-sented data reflect the experience of a high-volume ter-tiary care cardiology department. Second, due to theretrospective and observational character of the study,there was no prospective randomisation of cases,although the baseline STS score showed good agreementbetween the two groups after the performed matchingprocess. Moreover, due to the manual matching a poten-tial bias could have been introduced as compared with anautomated process. Furthermore, the number of thereported combined cases and the respective event ratesare low. Therefore, the issues of safety and net clinicalbenefit cannot be cleared definitively on the basis of thepresent study.
ConclusionsTranscatheter treatment of combined cardiac diseases isfeasible even in a single session in high-volume centreswith experienced operators. However, for definite proofof safety comparable to TAVI-only procedures, largernumbers of combined procedures or ideally, a controlled,prospective randomised study would be desirable.
Funding This research received no specific grant from any funding agency inthe public, commercial or not-for-profit sectors.
Competing interests BM has received lecture fees from AGA Medical; AK is aproctor of AGA’s LAA occlusion programme, SW and PW have receivedunrestricted grants from Medtronic and Edwards Lifesciences. FN, LB and AKare proctors for Edwards and Medtronic.
Provenance and peer review Not commissioned; externally peer reviewed.
Data sharing statement No additional data are available.
Open Access This is an Open Access article distributed in accordance withthe Creative Commons Attribution Non Commercial (CC BY-NC 3.0) license,which permits others to distribute, remix, adapt, build upon this work non-commercially, and license their derivative works on different terms, providedthe original work is properly cited and the use is non-commercial. See: http://creativecommons.org/licenses/by-nc/3.0/
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