Article

The Expanding Role of Echocardiography in Interventional Cardiology

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Abstract

Echocardiography provides excellent realtime imaging of the heart, making it the imaging modality of choice immediately before, during and after cardiac interventional procedures. It helps to guide case selection and execution of the intervention, evaluates the effects of the intervention and enables early detection of complications. Advances in the design and technology of medical devices and delivery systems, coupled with demand for alternative non-surgical therapies for common medical problems, have led to an increase in the volume, variety and complexity of non-coronary cardiac interventional procedures performed. Many of these procedures require a multidisciplinary team approach and demand optimal imaging to ensure successful outcomes. The aim of this article is to review the expanding role of echocardiography in non-coronary interventional cardiology in adults.

Keywords

Echocardiography, cardiac ultrasound, transoesophageal echocardiography, intra-cardiac echocardiography, 3D echocardiography, valvular heart disease, congenital heart disease, atrial septal defect, patent foramen ovale, balloon mitral valvuloplasty, mitral valve repair, aortic stenosis, transseptal catheterisation, pericardiocentesis, myocardial biopsy, alcohol septal ablation, left atrial appendage occlusion,

Disclosure:Lindsay A Smith has no conflicts of interest to declare. Amit Bhan has received honoraria from Philips. Mark J Monaghan has received research support and honoraria from GE, Philips, Siemens and TomTec.

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Accepted:

DOI:https://doi.org/10.15420/ecr.2010.6.2.71

Correspondence Details:Mark J Monaghan, Department of Non-Invasive Cardiology, King's College Hospital, Denmark Hill, London, SE5 9RS, UK. E: mark.monaghan@nhs.net

Copyright Statement:

The copyright in this work belongs to Radcliffe Medical Media. Only articles clearly marked with the CC BY-NC logo are published with the Creative Commons by Attribution Licence. The CC BY-NC option was not available for Radcliffe journals before 1 January 2019. Articles marked ‘Open Access’ but not marked ‘CC BY-NC’ are made freely accessible at the time of publication but are subject to standard copyright law regarding reproduction and distribution. Permission is required for reuse of this content.

The field of non-coronary cardiac intervention is undergoing rapid expansion, driven by advances in technology and increasing demand for alternative, non-surgical therapies for common structural heart diseases. As a result, the volume, variety and complexity of percutaneous catheter-based procedures being performed in cardiac catheterisation laboratories are increasing. Traditionally, fluoroscopy has been used to guide such procedures, but it has important limitations, such as significant radiation exposure, a 2D perspective and limited tissue differentiation, as well as the requirement for radiographic contrast use. The greater complexity of these newer procedures, particularly those involving heart valve intervention, necessitates more sophisticated and exacting imaging techniques, both to facilitate appropriate case selection and to provide procedural guidance, thus increasing the likelihood of successful outcome. Contemporary advances in echocardiography imaging techniques ensure these modalities are well suited to the imaging requirements of this exciting and expanding field of interventional cardiology.

Realtime 3D imaging, made possible by the development of a full matrix transducer capable of acquiring pyramidal-shaped ultrasound data sets, has been a major advance in transthoracic echocardiography (TTE). Furthermore, transducers and systems capable of single-beat 3D acquisitions, thus eradicating stitching artefacts, are now available. Miniaturisation of this 3D technology has enabled coupling with a transoesophageal echocardiography (TEE) probe providing high-quality 3D TEE images. Data acquisition with 3D TEE can be performed in three different modes: narrow-angle acquisition, displaying realtime images; 3D zoom mode, generating a realtime truncated pyramidal data set; and wide-angle full-volume mode, enabling a larger pyramidal data set but requiring electrocardiographic gating and acquisition over one to seven cardiac cycles. The wide-angle full-volume mode is currently the only mode to support colour Doppler imaging. Unlike the cumbersome 3D predecessors, current data sets can be readily manipulated either online or offline to display cardiac structures or to enable quantitative analysis.

Intra-cardiac echocardiography (ICE) is a recent application of ultrasound technology that offers imaging of comparable or even superior quality to TEE. Early ICE acquired cross-sectional images using a rotating transducer similar to intra-vascular ultrasound (rotational ICE). The incorporation of miniaturised phased-array technology into an intra-cardiac catheter has now enabled sector-based imaging (phased-array ICE). Rotational ICE provides good near-field but more limited far-field imaging. However, phased-array ICE has deeper penetration and better far-field imaging than rotational ICE, in addition to being steerable and allowing Doppler imaging.

The ideal echocardiography modality would provide high-quality, realtime 3D imaging in a format easily comprehended by the interventional cardiologist, with minimal interference to the flow of the interventional procedure being performed. It would be safe, minimally invasive and widely available at low cost. Currently, no one echocardiography imaging modality fulfils all these criteria. Each has relative advantages and disadvantages compared with the others (see Table 1). Therefore, selection of the optimal imaging modality for any given interventional cardiac procedure must take into account both the specific requirements of the procedure and the relative strengths and weaknesses of the imaging modality to ensure the greatest likelihood of successful outcome.

Congenital and Acquired Septal Defects
Percutaneous Atrial Septal Defect/Patent Foramen Ovale Device Closure

Percutaneous device closure is increasingly the therapy of choice for patients with atrial septal defect (ASD) or patent foramen ovale (PFO), where clinically appropriate and in the absence of complicated cardiac anatomy or other indications for cardiac surgery.1,2 In experienced hands, it is a safe and effective procedure with a risk of serious complications, such as device embolisation, of less than 1%.3 It improves functional status in symptomatic patients and exercise capacity in both asymptomatic and symptomatic patients, although long-term follow-up safety and efficacy data are awaited.4,5

Echocardiography plays a key role before, during and after percutaneous ASD/PFO device closure. Indeed, its use for procedural guidance, in addition to primary fluoroscopy, was recently recommended by the American Society of Echocardiography (ASE).6 Typically, the diagnosis of an inter-atrial shunt is made by TTE with colour Doppler and/or agitated saline or gelofusin contrast injection. TTE also provides information about the type of defect, its haemodynamic significance and any associated anomalies. However, if percutaneous closure is clinically indicated, detailed assessment of the inter-atrial septal anatomy and surrounding structures is required by either TEE or ICE.

Systematic evaluation of the inter-atrial septum and surrounding structures should be performed to determine defect type, size and PFO tunnel length, the presence of fenestrations, aneurysmal septum or prominent Eustachian valve or Chiari network, and to exclude associated abnormality of the inferior and superior vena cavae, pulmonary veins, coronary sinus and atrioventricular valves. Furthermore, consideration of the size of the defect rims and total atrial septal length are important in determining the likelihood of procedural success.7,8 This evaluation enables the interventional cardiologist to plan the procedure and to choose from a variety of ASD and PFO closure devices with differing designs and characteristics. Currently, only isolated ostium secundum type ASDs and PFOs are suitable for device closure. Possible contraindications to device closure identified by echocardiography therefore include very large (>38mm) or multiple defects, deficient (<5mm, circumferential extent >1/3) rims, close proximity of the defect to the atrioventricular valves, sinus venosus defects, anomalous pulmonary venous drainage, ASD with severe pulmonary hypertension and bi-directional or right-to-left shunting and intra-cardiac thrombus. Intra-procedural imaging (TEE or ICE) facilitates wire and catheter manipulation and positioning, balloon sizing of the defect and device deployment, as well as enabling pre- and post-closure assessment of adjacent cardiac structures and early identification of complications such as pericardial effusion.9–13 Following device closure, TTE is indicated at routine intervals to confirm device stability, evaluate the presence of any residual shunt and detect the development of late complications.11,14,15

The advent of realtime 3D TEE has enhanced the evaluation of ASDs. 2D echocardiography may underestimate both the size and complexity of an ASD; however, 3D echocardiography clearly defines inter-atrial septal anatomy and enables an en face view of the defect (see Figure 1A).16–18 Multiplanar reconstruction of the 3D data set allows accurate measurement of the minimum and maximum dimensions of the defect, facilitating selection of the optimal size and type of closure device (see Figure 1B).19 Moreover, intra-procedural realtime 3D TEE, in addition to 2D, provides superior visualisation of wires, catheters and devices and their relationships to neighbouring structures in a format that is generally more intuitively comprehended by the interventional cardiologist (see Figures 1C and 1D). The advantages of realtime 3D TEE in guiding cardiac catheter interventions are increasingly recognised.20,21

ICE is also commonly used to guide ASD/PFO device closure in many centres. It provides comparable imaging of the inter-atrial septum and surrounding structures to 2D TEE, and indeed may enable superior visualisation of the inferoposterior inter-atrial septum.11,12,22 However, it also has the distinct advantages of requiring neither general anaesthesia nor additional echocardiographic support, as it may be performed by the primary operator. As such, ICE has been shown to reduce fluoroscopy and procedure times, as well as offering comparable cost to procedures performed under general anaesthesia with TEE guidance.9,10,22,23 However, potential disadvantages of ICE include limited far-field view, lack of catheter stability, the expense of single-use ICE catheters, the need for additional training and possible provocation of atrial arrhythmias, as well as difficulty for the single operator manipulating both the ICE catheter and the device at the time of deployment.

Percutaneous Ventricular Septal Defect Closure

Successful percutaneous closure of post-myocardial infarction ventricular septal defect (VSD) has been reported.24,25 Echocardiography (often TTE) confirms the diagnosis of VSD and provides information regarding shunt size and haemodynamic significance. 3D TEE may be required to accurately define and size the defect by enabling en face visualisation, thus determining the size of closure device to be used as well as guiding the closure procedure.25

Valvular Heart Disease
Balloon Mitral Valvuloplasty

Balloon mitral valvuloplasty (BMV) is a well-established therapeutic option for patients with symptomatic mitral stenosis and appropriate anatomy. In addition to its role in the evaluation of the aetiology and severity of mitral stenosis and in case selection, TTE is used in many centres with fluoroscopy to guide BMV. TTE is a useful adjunct to fluoroscopy in transseptal puncture, provides immediate assessment of the results of valvuloplasty (visualisation of valve anatomy, determination of transvalvular gradients and mitral valve area, detection of mitral regurgitation) and allows early detection of complications.26 However, the need for TTE imaging may interfere with the execution of the procedure and may provide sub-optimal images in some patients. Alternatively, guidance may be provided with TEE or ICE.27–31 TEE is superior to TTE in excluding left atrial and left atrial appendage thrombi and in monitoring wire and balloon positioning. Newer phased-array ICE catheters now provide Doppler imaging, thus enabling comparable imaging to 2D TEE. The use of echocardiography guidance during this procedure has been shown to improve procedural success and reduce complication rates; it may also reduce procedural and fluoroscopic times.31–33 The advent of 3D TTE and TEE has enabled more accurate evaluation of mitral stenosis, and in particular of mitral valve area using multiplanar reconstruction from the 3D data set to ensure correct alignment with the often eccentric mitral valve orifice.34–37

Percutaneous Mitral Valve Repair

The role of echocardiography in assessing the aetiology and severity of mitral valve disease, as well as in guiding therapeutic strategy and prognosis, is well established. More recently, it has become clear that comprehensive characterisation of the mitral valve apparatus requires 3D TTE and TEE.38 New percutaneous mitral valve repair systems are being developed that offer a possible therapeutic option for those patients at high surgical risk. One such system, with promising early results, uses a catheter-based approach to deliver a ‘clip’ placed on the mitral valve leaflet tips, essentially creating an edge-to-edge repair.39–41 However, this approach mandates careful case selection using a combination of TTE and TEE to assess aetiology and severity of mitral regurgitation and suitability for the percutaneous clipping procedure. In particular, detailed evaluation must consider mitral valve leaflet flail gap and width, leaflet coaptation length and mitral valve area, as well as confirming the presence of secondary chordal support and the absence of leaflet cleft.

The percutaneous mitral valve clipping procedure itself is guided primarily by TEE. This is essential, first to guide precise localisation of the transseptal puncture to the superior and posterior portion of the inter-atrial septum, facilitating approach to the mitral valve. Next, TEE ensures correct alignment of the advancing clip perpendicular to the plane of the mitral valve, and of the open arms perpendicular to the coaptation line. After leaflet grasping, leaflet approximation, severity of mitral regurgitation and transmitral gradients are assessed and then final clip deployment visualised (see Figure 2). As with other interventional procedures, TEE enables prompt detection and evaluation of any complications. Subsequent routine TTE at regular intervals enables monitoring of clip stability, severity of any residual mitral regurgitation, transmitral gradients and effects on cardiac chamber size and function.

3D TEE is essential to enable thorough assessment of mitral valve anatomy, including localisation of individual leaflet scallops and, using 3D colour, to accurately localise the origin of regurgitant jets.42 As such, 3D TEE plays a significant role in the planning of mitral valve repair, whether by a surgical or percutaneous route.43 The 3D zoom mode is unique in enabling visualisation of the mitral valve, both from the left atrial aspect in surgical orientation and from the left ventricular aspect. This latter view is particularly helpful when assessing clip orientation relative to the line of coaptation as an alternative to the 2D transgastric view, which may be difficult to achieve satisfactorily in some patients.

Transcatheter Aortic Valve Implantation

Transcatheter aortic valve implantation (TAVI) provides a percutaneous treatment option for those patients with aortic stenosis with conventional indications for aortic valve surgery but who have unacceptably high surgical risk.44–47 Currently, two devices, with differing construction and characteristics, are being implanted: the Cribier-Edwards bio-prosthesis (Edwards Lifesciences LLC, Irvine, CA) and the CoreValve aortic valve prosthesis (CoreValve Inc., Irvine, CA). The Cribier-Edwards bio-prosthesis is a balloon-expandable tri-leaflet bovine pericardial valve mounted within a tubular stainless steel stent that may be implanted via a transfemoral or a transapical route. The CoreValve is a tri-leaflet pericardial tissue valve mounted in a self-expanding nitinol stent. Echocardiography has a vital role in the evaluation of patients with aortic stenosis, in assessment of suitability for TAVI, in guiding the implantation procedure and in subsequent follow-up.48–50

Initial evaluation is performed with TTE, with more detailed imaging of the aortic valve and surrounding structures performed with TEE, either prior to (if there are concerns regarding suitability) or at the time of the TAVI procedure. Multiple echocardiographic factors should be taken into consideration when assessing suitability for TAVI, implantation route and choice of valve size, all of which are crucial in determining the likelihood of successful outcome. These factors include: aortic valve and root morphology (annulus and sinus of Valsalva size and geometry, severity and eccentricity of leaflet calcification); position of the coronary ostia relative to the aortic valve leaflets and any calcification; morphology of the left ventricular outflow tract (LVOT) and aortomitral continuity (proximal septal hypertrophy, presence of calcification); and left ventricular cavity size.

During the TAVI procedure, TEE provides realtime imaging to assist wire and catheter placement, to assess the effects of balloon valvuloplasty and ensure correct positioning of the aortic valve prosthesis, to assess for paraprosthetic regurgitation immediately following implantation and to evaluate any complications that may occur (see Figure 3).48,49 TTE is performed prior to discharge and subsequently at regular intervals to monitor function of the aortic valve prosthesis.50

Percutaneous Closure of Prosthetic Paravalvular Leaks

Prosthetic valve dehiscence is a recognised complication following valve replacement surgery and may lead to severe paravalvular regurgitation and heart failure. In those patients for whom re-do valve surgery is considered to be too high-risk, percutaneous implantation of an occlusion device in the dehisced region of the prosthetic valve has been performed.51,52 TTE and TEE are used to establish the diagnosis and TEE to guide the intervention. 3D TEE is important in exactly delineating the anatomy, allowing appropriate case selection for percutaneous device closure, and in enabling realtime imaging during the procedure.25

Electrophysiology
Atrial Fibrillation Ablation

Echocardiography, predominantly ICE, is used widely in electrophysiology laboratories to guide ablative procedures, particularly atrial fibrillation (AF) ablation. The relative advantages of ICE over TTE and TEE described earlier make it particularly suited to use in this environment.

Many specific cardiac arrhythmias are dependent on the underlying anatomy, and there is therefore a need to deliver ablative therapy at precise anatomical locations; ICE facilitates this by providing excellent realtime imaging and feedback. TTE has a well-established role in assessing cardiac structure and function in patients with AF and in detecting complications before and after ablation procedures. TEE is the imaging modality of choice for exclusion of left atrial thrombus, a contraindication to ablation therapy.

ICE is useful in guiding transseptal puncture, and may reduce the risk of complications compared with fluoroscopic guidance alone, particularly where there is unusual anatomy or where a second puncture is required.53,54 Furthermore, ICE enables precise localisation of the site of transseptal puncture, facilitating access to specific sites within the left atrium.55 Subsequently, ICE is used to determine pulmonary vein anatomy and physiology prior to ablation, to assist and confirm catheter positioning, to confirm catheter tip–tissue contact and stability and to monitor for potential procedural complications such as the formation of microbubbles (indicating excessive tissue heating), pericardial effusion, thrombus formation and pulmonary vein stenosis.56–58 ICE has also been used with success in ablative procedures for other cardiac arrhythmias.59–61 Recent ASE guidance recommends the use of ICE for radiofrequency ablation for AF.6 Some centres successfully use TEE (including 3D) to guide transseptal puncture (see Figure 4) and, in addition to fluoroscopy and computed tomographical reconstruction, to guide pulmonary vein ablation procedures for patients with AF, although this practice is much less common.25

Miscellaneous
Pericardiocentesis

Echocardiography is often used to guide needle pericardiocentesis, in addition to fluoroscopy, and may reduce procedure-related complications.62 TTE determines the size and location of the pericardial effusion, factors important in deciding the site of approach and needle trajectory. Once the catheter is positioned in the pericardial space, its location can be confirmed by the injection of agitated saline.

Myocardial Biopsy

While myocardial biopsy is typically performed with fluoroscopy alone, some centres use adjunctive TTE or, in selected patients, even TEE or ICE.63,64 Echocardiography guidance enables greater choice of site for the biopsy and may reduce the risk of complications.63 TEE has also been used in selected cases to guide biopsy of intra-cardiac and intra-vascular masses.65

Alcohol Septal Ablation

Alcohol septal ablation is performed in selected patients with symptomatic hypertrophic obstructive cardiomyopathy refractory to medical therapy.66 This technique involves the injection of ethanol into a septal perforator branch of the left anterior descending artery, causing localised infarction in the hypertrophied proximal ventricular septum. Echocardiography guidance is typically performed during the procedure with TTE, although TEE or ICE may be used as an alternative in some centres, with favourable results.66–68 The left ventricular outflow tract and mitral valve anatomy and function are evaluated and the correct target septal perforator identified using echocardiography contrast injection to ensure perfusion of the desired region of the septum prior to ethanol injection. The latter technique has been reported to affect interventional strategy in 15–20% of cases.69 TTE or TEE also enables immediate evaluation of results and monitoring for complications.

Left Atrial Appendage Device Occlusion

Percutaneous left atrial appendage (LAA) occlusion devices are currently under development and undergoing evaluation in clinical trials. While preliminary data have shown LAA device occlusion to be safe and feasible, it is uncertain whether it will prevent thromboembolic stroke in patients with AF.70 The LAA occlusion device is placed via a percutaneous transcatheter approach via a transseptal puncture to access the left atrium using fluoroscopic and TEE guidance. TEE is required to guide transseptal puncture, to size the ostium of the LAA to enable selection of the appropriate size ofocclusion device and to ensure optimal device placement and complete occlusion of the LAA. It also enables detection of complications. 3D TEE imaging enables excellent device visualisation with respect to the LAA.

Future Directions

It is likely that the exciting field of non-coronary cardiac intervention will continue to expand and evolve, necessitating advances in echocardiography technology to keep apace to support this development. Important advances will be seen in all the echocardiography modalities. Future developments that will further extend the role of ICE in the cardiac laboratory may include reduction in catheter size and improved catheter stability and handling, enhanced image quality and the development of realtime 3D imaging. Other potential advances include the integration of ICE into current electro-anatomical mapping systems and also coupling of ICE and ablative therapy into a single catheter.71 Recent development of a neonatal TEE probe small and flexible enough to allow transnasal insertion in adults has a potential application in interventional cardiology. The transnasal approach, typically better tolerated by patients, may offer the distinct advantage of enabling some interventional procedures requiring TEE guidance to be performed without general anaesthesia. However, acceptable image quality and good patient tolerance with this application are yet to be demonstrated in scientific evaluations. It is likely that a single TTE transducer with integrated 2D and 3D capability will be available soon, and this will greatly aid workflow. Increases in processing power will lead to greater temporal and spatial resolution, further improving image quality. In addition, developments in software and workflow, taking into consideration the particular demands of procedural imaging, will also aid the interventional echocardiologist.

References

  1. Harper RW, Mottram PM, McGaw DJ, Closure of secundum atrial septal defects with the Amplatzer septal occluder device: techniques and problems, Catheter Cardiovasc Interv, 2002;57(4):508–24.
    Crossref | PubMed
  2. Butera G, Romagnoli E, Carminati M, et al., Treatment of isolated secundum atrial septal defects: impact of age and defect morphology in 1,013 consecutive patients, Am Heart J, 2008;156(4):706–12.
    Crossref | PubMed
  3. Butera G, Carminati M, Chessa M, et al., Percutaneous versus surgical closure of secundum atrial septal defect: comparison of early results and complications, Am Heart J, 2006;151(1):228–34.
    Crossref | PubMed
  4. Brochu MC, Baril JF, Dore A, et al., Improvement in exercise capacity in asymptomatic and mildly symptomatic adults after atrial septal defect percutaneous closure, Circulation, 2002;106(14):1821–6.
    Crossref | PubMed
  5. Du ZD, Hijazi ZM, Kleinman CS, et al., Comparison between transcatheter and surgical closure of secundum atrial septal defect in children and adults: results of a multicenter nonrandomized trial, J Am Coll Cardiol, 2002;39(11):1836–44.
    Crossref | PubMed
  6. Silvestry FE, Kerber RE, Brook MM, et al., Echocardiography-guided interventions, J Am Soc Echocardiogr, 2009;22(3):213–31; quiz 316–217.
    Crossref | PubMed
  7. Cooke JC, Gelman JS, Harper RW, Echocardiologists’ role in the deployment of the Amplatzer atrial septal occluder device in adults, J Am Soc Echocardiogr, 2001;14(6):588––94.
    Crossref | PubMed
  8. Podnar T, Martanovic P, Gavora P, Masura J, Morphological variations of secundum-type atrial septal defects: feasibility for percutaneous closure using Amplatzer septal occluders, Catheter Cardiovasc Interv, 2001;53(3):386–91.
    Crossref | PubMed
  9. Butera G, Chessa M, Bossone E, et al., Transcatheter closure of atrial septal defect under combined transesophageal and intracardiac echocardiography, Echocardiography, 2003;20(4):389–90.
    Crossref | PubMed
  10. Boccalandro F, Baptista E, Muench A, et al., Comparison of intracardiac echocardiography versus transesophageal echocardiography guidance for percutaneous transcatheter closure of atrial septal defect, Am J Cardiol, 2004;93(4):437–40.
    Crossref | PubMed
  11. Earing MG, Cabalka AK, Seward JB, et al., Intracardiac echocardiographic guidance during transcatheter device closure of atrial septal defect and patent foramen ovale, Mayo Clin Proc, 2004;79(1):24–34.
    Crossref | PubMed
  12. Hijazi Z, Wang Z, Cao Q, et al., Transcatheter closure of atrial septal defects and patent foramen ovale under intracardiac echocardiographic guidance: feasibility and comparison with transesophageal echocardiography, Catheter Cardiovasc Interv, 2001;52(2):194–9.
    Crossref | PubMed
  13. Zanchetta M, Onorato E, Rigatelli G, et al., Intracardiac echocardiography-guided transcatheter closure of secundum atrial septal defect: a new efficient device selection method, J Am Coll Cardiol, 2003;42(9):1677–82.
    Crossref | PubMed
  14. Justo RN, Nykanen DG, Boutin C, et al., Clinical impact of transcatheter closure of secundum atrial septal defects with the double umbrella device, Am J Cardiol, 1996;77(10): 889–92.
    Crossref | PubMed
  15. Agarwal SK, Ghosh PK, Mittal PK, Failure of devices used for closure of atrial septal defects: mechanisms and management, J Thorac Cardiovasc Surg, 1996;112(1):21–6.
    Crossref | PubMed
  16. Marx GR, Sherwood MC, Fleishman C, Van Praagh R, Three-dimensional echocardiography of the atrial septum, Echocardiography, 2001;18(5):433–43.
    Crossref | PubMed
  17. Franke A, Kuhl HP, Rulands D, et al., Quantitative analysis of the morphology of secundum-type atrial septal defects and their dynamic change using transesophageal threedimensional echocardiography, Circulation, 1997;96 (9 Suppl.):II-323–7.
    PubMed
  18. van den Bosch AE, Ten Harkel DJ, McGhie JS, et al., Characterization of atrial septal defect assessed by realtime 3-dimensional echocardiography, J Am Soc Echocardiogr, 2006;19(6):815–21.
    Crossref | PubMed
  19. Pepi M, Tamborini G, Bartorelli AL, et al., Usefulness of three-dimensional echocardiographic reconstruction of the Amplatzer septal occluder in patients undergoing atrial septal closure, Am J Cardiol, 2004;94(10):1343–7.
    Crossref | PubMed
  20. Balzer J, Kuhl H, Rassaf T, et al., Real-time transesophageal three-dimensional echocardiography for guidance of percutaneous cardiac interventions: first experience, Clin Res Cardiol, 2008;97(9):565–74.
    Crossref | PubMed
  21. Ben Zekry S, Guthikonda S, Little SH, et al., Percutaneous closure of atrial septal defect, JACC Cardiovasc Imaging, 2008;1(4):515–17.
    Crossref | PubMed
  22. Zanchetta M, Pedon L, Rigatelli G, et al., Intracardiac echocardiography evaluation in secundum atrial septal defect transcatheter closure, Cardiovasc Intervent Radiol, 2003;26(1):52–7.
    Crossref | PubMed
  23. Mullen MJ, Dias BF, Walker F, et al., Intracardiac echocardiography guided device closure of atrial septal defects, J Am Coll Cardiol, 2003;41(2):285–92.
    Crossref | PubMed
  24. Mullasari AS, Umesan CV, Krishnan U, et al., Transcatheter closure of post-myocardial infarction ventricular septal defect with Amplatzer septal occluder, Catheter Cardiovasc Interv, 2001;54(4):484–7.
    Crossref | PubMed
  25. Perk G, Lang RM, Garcia-Fernandez MA, et al., Use of real time three-dimensional transesophageal echocardiography in intracardiac catheter based interventions, J Am Soc Echocardiogr, 2009;22(8):865–82.
    Crossref | PubMed
  26. Pandian NG, Isner JM, Hougen TJ, et al., Percutaneous balloon valvuloplasty of mitral stenosis aided by cardiac ultrasound, Am J Cardiol, 1987;59(4):380–81.
    Crossref | PubMed
  27. Salem MI, Makaryus AN, Kort S, et al., Intracardiac echocardiography using the AcuNav ultrasound catheter during percutaneous balloon mitral valvuloplasty, J Am Soc Echocardiogr, 2002;15(12):1533–7.
    Crossref | PubMed
  28. Green NE, Hansgen AR, Carroll JD, Initial clinical experience with intracardiac echocardiography in guiding balloon mitral valvuloplasty: technique, safety, utility, and limitations, Catheter Cardiovasc Interv, 2004;63(3):385–94.
    Crossref | PubMed
  29. Goldstein SA, Campbell A, Mintz GS, et al., Feasibility of on-line transesophageal echocardiography during balloon mitral valvulotomy: experience with 93 patients, J Heart Valve Dis, 1994;3(2):136–48.
    PubMed
  30. Goldstein SA, Campbell AN, Mitral stenosis. Evaluation and guidance of valvuloplasty by transesophageal echocardiography, Cardiol Clin, 1993;11(3):409–25.
    PubMed
  31. Park SH, Kim MA, Hyon MS, The advantages of on-line transesophageal echocardiography guide during percutaneous balloon mitral valvuloplasty, J Am Soc Echocardiogr, 2000;13(1):26–34.
    Crossref | PubMed
  32. Chiang CW, Hsu LA, Chu PH, et al., On-line multiplane transesophageal echocardiography for balloon mitral commissurotomy, Am J Cardiol, 1998;81(4):515–18.
    Crossref | PubMed
  33. Applebaum RM, Kasliwal RR, Kanojia A, et al., Utility of three-dimensional echocardiography during balloon mitral valvuloplasty, J Am Coll Cardiol, 1998;32(5):1405–9.
    Crossref | PubMed
  34. Sugeng L, Coon P, Weinert L, et al., Use of real-time 3-dimensional transthoracic echocardiography in the evaluation of mitral valve disease, J Am Soc Echocardiogr, 2006;19(4):413–21.
    Crossref | PubMed
  35. de Agustin JA, Nanda NC, Gill EA, et al., The use of threedimensional echocardiography for the evaluation of and treatment of mitral stenosis, Cardiol Clin, 2007;25(2):311–18.
    Crossref | PubMed
  36. Zamorano J, Cordeiro P, Sugeng L, et al., Real-time threedimensional echocardiography for rheumatic mitral valve stenosis evaluation: an accurate and novel approach, J Am Coll Cardiol, 2004;43(11):2091–6.
    Crossref | PubMed
  37. Langerveld J, Valocik G, Plokker HW, et al., Additional value of three-dimensional transesophageal echocardiography for patients with mitral valve stenosis undergoing balloon valvuloplasty, J Am Soc Echocardiogr, 2003;16(8):841–9.
    Crossref | PubMed
  38. Salcedo EE, Quaife RA, Seres T, Carroll JD, A framework for systematic characterization of the mitral valve by real-time three-dimensional transesophageal echocardiography, J Am Soc Echocardiogr, 2009;22(10):1087–99.
    Crossref | PubMed
  39. Feldman T, Kar S, Rinaldi M, et al., Percutaneous mitral repair with the MitraClip system: safety and midterm durability in the initial EVEREST (Endovascular Valve Edgeto- Edge REpair Study) cohort, J Am Coll Cardiol, 2009;54(8): 686–94.
    Crossref | PubMed
  40. Feldman T, Wasserman HS, Herrmann HC, et al., Percutaneous mitral valve repair using the edge-to-edge technique: six-month results of the EVEREST Phase I Clinical Trial, J Am Coll Cardiol, 2005;46(11):2134–40.
    Crossref | PubMed
  41. Herrmann HC, Rohatgi S, Wasserman HS, et al., Mitral valve hemodynamic effects of percutaneous edge-toedge repair with the MitraClip device for mitral regurgitation, Catheter Cardiovasc Interv, 2006;68(6):821–8.
    Crossref | PubMed
  42. Sugeng L, Shernan SK, Weinert L, et al., Real-time threedimensional transesophageal echocardiography in valve disease: comparison with surgical findings and evaluation of prosthetic valves, J Am Soc Echocardiogr, 2008;21(12):1347–54.
    Crossref | PubMed
  43. Chauvel C, Bogino E, Clerc P, et al., Usefulness of threedimensional echocardiography for the evaluation of mitral valve prolapse: an intraoperative study, J Heart Valve Dis, 2000;9(3):341–9.
    PubMed
  44. Cribier A, Eltchaninoff H, Tron C, et al., Early experience with percutaneous transcatheter implantation of heart valve prosthesis for the treatment of end-stage inoperable patients with calcific aortic stenosis, J Am Coll Cardiol, 2004;43(4):698–703.
    Crossref | PubMed
  45. Lichtenstein SV, Cheung A, Ye J, et al., Transapical transcatheter aortic valve implantation in humans: initial clinical experience, Circulation, 2006;114(6):591–6.
    Crossref | PubMed
  46. Webb JG, Pasupati S, Humphries K, et al., Percutaneous transarterial aortic valve replacement in selected high-risk patients with aortic stenosis, Circulation, 2007;116(7):755–63.
    Crossref | PubMed
  47. Vahanian A, Alfieri O, Al-Attar N, et al., Transcatheter valve implantation for patients with aortic stenosis: a position statement from the European Association of Cardio-Thoracic Surgery (EACTS) and the European Society of Cardiology (ESC), in collaboration with the European Association of Percutaneous Cardiovascular Interventions (EAPCI), Eur Heart J, 2008;29(11):1463–70.
    Crossref | PubMed
  48. Moss RR, Ivens E, Pasupati S, et al., Role of echocardiography in percutaneous aortic valve implantation, JACC Cardiovasc Imaging, 2008;1(1):15–24.
    Crossref | PubMed
  49. Berry C, Oukerraj L, Asgar A, et al., Role of transesophageal echocardiography in percutaneous aortic valve replacement with the CoreValve Revalving system, Echocardiography, 2008;25(8):840–48.
    Crossref | PubMed
  50. Bauer F, Lemercier M, Zajarias A, et al., Immediate and long-term echocardiographic findings after transcatheter aortic valve implantation for the treatment of aortic stenosis: the Cribier-Edwards/Edwards-Sapien valve experience, J Am Soc Echocardiogr, 23(4):370–76.
    Crossref | PubMed
  51. Kim MS, Casserly IP, Garcia JA, et al., Percutaneous transcatheter closure of prosthetic mitral paravalvular leaks: are we there yet?, JACC Cardiovasc Interv, 2009;2(2):81–90.
    Crossref | PubMed
  52. Webb JG, Pate GE, Munt BI, Percutaneous closure of an aortic prosthetic paravalvular leak with an Amplatzer duct occluder, Catheter Cardiovasc Interv, 2005;65(1):69–72.
    Crossref | PubMed
  53. Hahn K, Gal R, Sarnoski J, et al., Transesophageal echocardiographically guided atrial transseptal catheterization in patients with normal-sized atria: incidence of complications, Clin Cardiol, 1995;18(4): 217–20.
    Crossref | PubMed
  54. Daoud EG, Kalbfleisch SJ, Hummel JD, Intracardiac echocardiography to guide transseptal left heart catheterization for radiofrequency catheter ablation, J Cardiovasc Electrophysiol, 1999;10(3):358–63.
    Crossref | PubMed
  55. Bazaz R, Schwartzman D, Site-selective atrial septal puncture, J Cardiovasc Electrophysiol, 2003;14(2):196–9.
    Crossref | PubMed
  56. Mangrum JM, Mounsey JP, Kok LC, DiMarco JP, Haines DE, Intracardiac echocardiography-guided, anatomically based radiofrequency ablation of focal atrial fibrillation originating from pulmonary veins, J Am Coll Cardiol, 2002;39(12):1964–72.
    Crossref | PubMed
  57. Saad EB, Marrouche NF, Saad CP, et al., Pulmonary vein stenosis after catheter ablation of atrial fibrillation: emergence of a new clinical syndrome, Ann Intern Med, 2003;138(8):634–8.
    Crossref | PubMed
  58. Marrouche NF, Martin DO, Wazni O, et al., Phased-array intracardiac echocardiography monitoring during pulmonary vein isolation in patients with atrial fibrillation: impact on outcome and complications, Circulation, 2003;107(21):2710–16.
    Crossref | PubMed
  59. Olgin JE, Kalman JM, Fitzpatrick AP, Lesh MD, Role of right atrial endocardial structures as barriers to conduction during human type I atrial flutter. Activation and entrainment mapping guided by intracardiac echocardiography, Circulation, 1995;92(7):1839–48.
    Crossref | PubMed
  60. Okishige K, Kawabata M, Yamashiro K, et al., Clinical study regarding the anatomical structures of the right atrial isthmus using intra-cardiac echocardiography: implication for catheter ablation of common atrial flutter, J Interv Card Electrophysiol, 2005;12(1):9–12.
    Crossref | PubMed
  61. Kalman JM, Olgin JE, Karch MR, et al., “Cristal tachycardias”: origin of right atrial tachycardias from the crista terminalis identified by intracardiac echocardiography, J Am Coll Cardiol, 1998;31(2):451–9.
    Crossref | PubMed
  62. Tsang TS, Barnes ME, Hayes SN, et al., Clinical and echocardiographic characteristics of significant pericardial effusions following cardiothoracic surgery and outcomes of echo-guided pericardiocentesis for management: Mayo Clinic experience, 1979–1998, Chest, 1999;116(2):322–31.
    Crossref | PubMed
  63. Ragni T, Martinelli L, Goggi C, et al., Echo-controlled endomyocardial biopsy, J Heart Transplant, 1990;9(5):538–42.
    PubMed
  64. Miller LW, Labovitz AJ, McBride LA, et al., Echocardiography-guided endomyocardial biopsy. A 5-year experience, Circulation, 1988;78(5 Pt 2):III99–102.
    PubMed
  65. Segar DS, Bourdillon PD, Elsner G, et al., Intracardiac echocardiography-guided biopsy of intracardiac masses, J Am Soc Echocardiogr, 1995;8(6):927–9.
    Crossref | PubMed
  66. Maron BJ, McKenna WJ, Danielson GK, et al., American College of Cardiology/European Society of Cardiology Clinical Expert Consensus Document on Hypertrophic Cardiomyopathy. A report of the American College of Cardiology Foundation Task Force on Clinical Expert Consensus Documents and the European Society of Cardiology Committee for Practice Guidelines, Eur Heart J, 2003;24(21):1965–91.
    Crossref | PubMed
  67. Faber L, Seggewiss H, Gleichmann U, Percutaneous transluminal septal myocardial ablation in hypertrophic obstructive cardiomyopathy: results with respect to intraprocedural myocardial contrast echocardiography, Circulation, 1998;98(22):2415–21.
    Crossref | PubMed
  68. Nagueh SF, Lakkis NM, He ZX, et al., Role of myocardial contrast echocardiography during nonsurgical septal reduction therapy for hypertrophic obstructive cardiomyopathy, J Am Coll Cardiol, 1998;32(1):225–9.
    Crossref | PubMed
  69. Faber L, Seggewiss H, Welge D, et al., Echo-guided percutaneous septal ablation for symptomatic hypertrophic obstructive cardiomyopathy: 7 years of experience, Eur J Echocardiogr, 2004;5(5):347–55.
    Crossref | PubMed
  70. Sick PB, Schuler G, Hauptmann KE, et al., Initial worldwide experience with the WATCHMAN left atrial appendage system for stroke prevention in atrial fibrillation, J Am Coll Cardiol, 2007;49(13):1490–95.
    Crossref | PubMed
  71. Kim SS, Hijazi ZM, Lang RM, Knight BP, The use of intracardiac echocardiography and other intracardiac imaging tools to guide noncoronary cardiac interventions, J Am Coll Cardiol, 2009;53(23):2117–28.
    Crossref | PubMed
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