OF INTRACARDIAC ECHOCARDIOGRAPHY IN INTERVENTIONAL PROCEDURES

Transcription

1 Imaging tehniques CLINICAL APPLICATIONS OF INTRACARDIAC ECHOCARDIOGRAPHY IN INTERVENTIONAL PROCEDURES Take the online multiple hoie questions assoiated with this artile (see page 990) BASICS See end of artile for authors affiliations Correspondene to: Dr Jeroen J Bax, Department of Cardiology, Leiden University Medial Center, Albinusdreef 2, 2333 ZA Leiden, The Netherlands; jbax@knoware.nl A M R M Jongbloed, M J Shalij, K Zeppenfeld, P V Oemrawsingh, E E van der Wall, J J Bax Heart 2005; 91: doi: /hrt urate knowledge of the anatomy of intraardia strutures is essential for the effiieny and safety of performing interventional proedures. Although fluorosopy is an important aid while advaning atheters in the heart, it is not suffiient to supply aurate anatomial information on the position of veins, ridges, and septa in the heart. Furthermore radiation exposure forms a risk to both the patient and the operator. Intraardia ehoardiography (ICE) is a promising tehnique for imaging of intraardia strutures, and may serve as an alternative for the transoesophageal approah, 1 whih is semiinvasive and requires anaesthesiology. The introdution of ICE atheters with low frequenies allows aurate visualisation of intraardia anatomial strutures with an ultrasound atheter plaed exlusively in the right side of the heart. This report fouses on the use of ICE in guiding perutaneous interventional proedures. OF INTRACARDIAC ECHOCARDIOGRAPHY History of two dimensional intraardia ultrasound systems The first appliation of ICE was done using mehanial ultrasound systems, whih were introdued in the 1980s. These systems provided high resolution imaging, but beause of the high frequeny of the transduers (20 40 MHz), tissue penetration was only limited and anatomi intraardia overviews ould not be obtained. The subsequent development of lower frequeny transduers allowed imaging of intraardia strutures, but these systems were still limited by the low steerability and over-the-wire design of the atheters. 2 The linial use was improved by the development of flexible lower frequeny transduers (9 MHz), but depth ontrol of these atheters still was not suffiient to allow visualisation of the whole heart from the right side of the heart. In the 1990s, systems modified after transoesophageal ehoardiographi probes were introdued. In these systems depth was improved by the use of lower frequenies (5 MHz). However, the large size of these transduers limited the linial use. In reent years the development of steerable phased array ultrasound atheter systems with low frequeny and Doppler qualities has expanded the linial use of ICE. What are the tehnial requirements? Mehanial ultrasound tipped atheter The mehanial ultrasound transduer tipped atheter (Clearview, Cardiovasular Imaging Systems In, Fremont, California, USA) an be used for both intravasular and intraardia imaging. For intraardia use, a 9 MHz single element transduer is inorporated in an 8 Frenh atheter. A piezoeletri rystal is rotated at 1800 rpm in the radial dimension perpendiular to the atheter shaft, thus providing ross setional images in a 360 radial plane. A sheath surrounding the imaging transduer is neessary to prevent ontat of the imaging transduer with the ardia wall. The ICE atheter needs to be filled with 3 5 ml sterile water before it is onneted to the ultrasound mahine (Boston Sientifi Corp, San Jose, California, USA). Three dimensional reonstrution of the aquired data an be reated. Phased array ultrasound tipped atheter This system uses a 10 Frenh ultrasound atheter (Aunav Diagnosti Ultrasound Catheter, Auson Corporation, Mountain View, California, USA), whih is positioned in the right atrium (RA) or right ventrile (RV) via a femoral approah, through a 10 Frenh introduer. The ultrasound atheter onsists of a miniaturised 64 element, phased array transduer, whih is inorporated in a single use atheter. The transduer sans in the longitudinal monoplane, providing a 90 setor image with tissue penetration of approximately 15 m. Two planes of bidiretional steering (anterior posterior and left right, eah in a diretion of 160 ) are possible by using a mehanism on the handle of the atheter. The high resolution multiple frequeny transduer (5 10 MHz) allows tissue penetration enhanement, thus allowing depth ontrol. 981 Heart: first published as /hrt on 14 June Downloaded from on 18 Otober 2018 by guest. Proteted by opyright.

2 982 Abbreviations ARVD/C: arrhythmogeni right ventriular dysplasia/ ardiomyopathy ASD: atrial septal defet ICE: intraardia ehoardiography LA: left atrium LAA: left atrial appendage LV: left ventrile PFO: patent foramen ovale PV: pulmonary vein RA: right atrium RV: right ventrile TOE: transoesophageal ehoardiography TTE: transthorai ehoardiography VT: ventriular tahyardia Measurements of haemodynami and physiologi variables an be made using Doppler imaging. The atheter is onneted to an ultrasound system (Aunav/Seqouia, Auson Corp, Mountain View, California, USA). Mehanial versus phased array ultrasound tipped atheter Although the mehanial ultrasound systems an be used at a onsiderably lower ost ompared to the phased array systems, there are several disadvantages as ompared to the phased array transduers. Currently, no funtional analysis an be performed with mehanial systems, due to the lak of olour and pulsed Doppler features. Sine these systems use a single ultrasound frequeny of 9 MHz and provide a limited radial depth of view (5 m), imaging of left sided strutures is not feasible with the ultrasound atheter plaed in the right heart. This ould inrease the risk of thromboemboli ompliations when using the devie for imaging of left sided strutures. Furthermore, the design of the mehanial rotating atheter shaft, and the lak of an artiulation mehanism at the handle, limits steering of the transduer and thus a dynami view on intraardia strutures. In the remainder of the urrent report we mainly fous on the use of phased array ICE in guiding perutaneous interventional proedures. Advantages and limitations of ICE during interventional proedures In the past, if perutaneous interventions needed guiding, fluorosopy, transthorai ehoardiography (TTE), or transoesophageal ehoardiography (TOE) were used. The use of ICE has several advantages over these other tehniques. No radiation is needed. In omparison to TOE, patient disomfort is less and general anaesthesia is not needed, allowing ommuniation with the patient during the proedure. As ompared to TTE, the transvenous aess has the advantage that it is not neessary to position a transduer in a sterile field. General advantages of ICE are the availability of diret online information on the position of atheters and devies, and the possibility of diret monitoring of aute proedure related ompliations (suh as thrombus formation, periardial effusion, et). Several limitations of ICE urrently exist. First the onsiderable shaft size (10 Frenh) and the lak of additional atheter features, suh as ports for guidewires, therapeuti devies and pressure, form a limitation. Seond, the phased array atheters are expensive and single use only. Third, phased array ICE provides only monoplane image setions. Although this an partly be overome by the steerability of the atheter, operators who are used to multiplane TOE transduers may have diffiulty obtaining the same views. Moreover, no standard views for ICE are urrently defined, as are available for TTE and TOE. Whih views an be obtained with ICE? Using phased array ICE, views of all anatomi landmarks an be obtained with the ultrasound atheter positioned in either the RA or the RV. Although images quite similar to TOE an be obtained, the relatively loose position of the ultrasound probe in the heart may give the inexperiened operator a feeling of disorientation. To overome this, strutured introdution and steering/manipulation of the ultrasound tipped atheter an ultimately provide orientation, supported by reognition of the anatomial landmarks. The atheter is advaned via the femoral vein, into the middle part of the RA via the inferior aval vein, thus visualising the RA, triuspid valve, and RV (fig 1A). This view with the atheter positioned in the middle of the RA an be used a basi point of orientation, from whih other views an be derived. Counterlokwise rotation with the atheter positioned in the superior part of the RA provides imaging of the terminal rest, whereas lokwise rotation of the atheter from the inferior RA provides a view of the Eustahian ridge with the triuspid aval isthmus (fig 1B); these are important target strutures in atrial flutter ablation. By turning the atheter around its axis (lokwise fashion as seen from the operator), imaging of the aorti valve, the right ventriular outflow trat, and the pulmonary artery is feasible (fig 1C). Long axis views of both aorta and pulmonary trunks an be imaged in the same plane, whih is not feasible with TOE. By rotating the atheter lokwise from the low right atrium, a short axis view of the oronary sinus an be obtained, while left-to-right movements of the ICE atheter provide a long axis view of this struture (fig 1D, E). When the atheter is further rotated, the next anatomial struture important in interventional ardiology to be reognised is the atrial septum (important for septal punture, see below). By ounterlokwise movement of the atheter from this position, imaging of the left atrium (LA), mitral valve, and left ventrile (LV) is performed (fig 1F). By inreasing the depth setting of the atheter with the transduer direted at the left atrial posterior wall, imaging of the left and right pulmonary veins and the left atrial appendage (LAA) is performed from the position of the atrial septum (important for pulmonary vein (PV) ablation, see below). As is it sometimes diffiult to distinguish between the LAA and the left superior PV, Doppler apaities an be used to differentiate. Finally, by advaning the atheter into the RV, detailed imaging of the LV an be obtained. Both long and short axis views of the LV an be obtained (fig 1G, H). CLINICAL APPLICATIONS The linial appliation of ICE in interventional proedures is listed in table 1. Detetion of intraardia thrombus Beause of the risk of systemi embolism, evaluation of the presene of intraardia thrombus before left sided proedures is mandatory. The risk of thromboemboli events is related to the presene of LA spontaneous ontrast and an LAA peak emptying veloity ( 20 m/s. 3 ICE an serve as an Heart: first published as /hrt on 14 June Downloaded from on 18 Otober 2018 by guest. Proteted by opyright.

3 Figure 1 Different views obtained with the intraardia ehoardiography (ICE) transduer in either the right atrium or the right ventrile. See text for explanation of panels A H. Ao, aorta; AP, pulmonary artery; CS, oronary sinus; Eust ridge, Eustahian ridge; IAS, interatrial septum; LA, left atrium; LV, left ventrile; Mitr valve, mitral valve; RA, right atrium; RV, right ventrile; RVOT, right ventriular outflow trat; Tri valve, triuspid valve; VCI, inferior aval vein. 983 Heart: first published as /hrt on 14 June Downloaded from alternative for TOE assessment of LA and LAA funtion 4 (fig 2 A,B). Before left sided interventions, the LAA an be evaluated for the presene of thrombus (fig 2C). The reported inidene of thromboemboli ompliations during left sided interventional proedures is approximately 2%, 5 possibly as high as 5% in patients with a history of transient ishaemi attaks. 6 Detetion of intraardia thrombus with ICE during left sided interventional proedures is disussed below (see PV ablation). Transseptal punture Potential life threatening ompliations of transseptal punture inlude aorti punture, periardial punture or tamponade, systemi arterial embolism, and perforation of the inferior aval vein. 7 Aurate visualisation of the fossa ovalis redues the risk of ompliations. Espeially less experiened operators may find ICE a better imaging modality then fluorosopy, by its ability to visualise aurately the target for transseptal punture, the fossa ovalis. 8 The Valsalva manoeuvre during injetion of saline/ontrast an be performed to reveal the presene of a patent foramen ovale (PFO) (fig 2D). In 10 20% a PFO is present, omitting the need for transseptal punture (fig 2E). Positioning of the ultrasound atheter in the RA provides a lear vision of the interatrial septum, whih onsist of a thiker part, the limbus, and the remains of the primary atrial septum, the fossa ovalis, whih is the safest on 18 Otober 2018 by guest. Proteted by opyright.

4 984 Table 1 Appliations of intraardia ehoardiography (ICE) in interventional proedures Evaluation of intraardia thrombus Transseptal punture Atrial septal defet/patent foramen ovale losure Interventional eletrophysiologial proedures pulmonary vein ablation in patients with atrial fibrillation atrial flutter ablation ventriular tahyardia ablation Other appliations diagnosis/biopsy of intraardia masses balloon mitral valvuloplasty atrial appendage olusion visualisation of oronary sinus target for the transseptal punture. During the punture a Brokenbrough needle (DAIG Corp) is inserted via a transseptal sheath and dilator system and direted towards the fossa ovalis. The first sign of a stable ontat of the transseptal dilator at the oval fossa, is tenting of the septum at this site (fig 2F). Suessful punture an be onfirmed by the appearane of ontrast in the LA after ontrast injetion. After withdrawal of the needle a mapping/ ablation atheter an be positioned in the LA. Guidane of losure of atrial septal defet and patent foramen ovale Perutaneous transatheter devie losure of atrial septal defet (ASD) and PFO has beome a safe and effiient alternative to open heart surgery. Guidane of these proedures by TOE is standard pratie and in reent years several studies have reported the feasibility and safety of ICE for guiding these proedures The losure of ASDs guided by TOE, without use of fluorosopy, has been desribed. However, although the proedure ould be satisfatorily performed in most ases without prolongation of proedure times, patients needed to undergo extensive TOE, and signifiantly higher doses of sedation were used. 11 Espeially for this appliation, when long and ontinuous ehoardiography imaging is required, ICE redues proedure and fluorosopy times, does not require general anaesthesia, and is less disomforting than TOE. 9 During these proedures, ICE is used to determine the size and loation of the defet in relation to ardia anatomy and the presene of rims and septal remnants. Clear visualisation of the ASD/PFO, RA, LA, sizing balloon and losure devie is feasible with a phased array atheter positioned in the RA (fig 3). Deployment of the devie an be evaluated using ICE. Partiularly when the remaining part of the septum is floppy, aurate evaluation of the stability of the losure devie using Doppler dynamis is neessary before releasing the devie. Guidane of interventional eletrophysiology proedures Pulmonary vein isolation proedures The observation that etopi foi originating in the PVs an initiate atrial fibrillation 12 has led to the development of perutaneous atheter ablation strategies aimed at ablation at the site of the PVs. Although results are promising, long proedure times and proedure related ompliations, suh as PV stenosis, are still hallenges for improvement. These issues are (in part) related to the fat that the ablation targets, the veno-atrial juntions and the PVs or their ostia, are not easily visualised using fluorosopy. Furthermore, interindividual variations in PV anatomy our, whih may require adjustment of the ablation strategy. During PV ablation proedures, ICE an provide information on the individual PV anatomy, suh as the number of PVs, the Heart: first published as /hrt on 14 June Downloaded from Figure 2 (A) Spontaneous ontrast in the left atrial appendage (LAA), a risk fator for thrombus formation. (B) Funtion of the LAA an be determined with phased array ICE, using pulsed wave Doppler. (C) Thrombus in the LAA. (D) The Valsalva manoeuvre is performed before transseptal punture to determine the presene of patent foramen ovale. Contrast bubbles an be observed in the right atrium (arrow). The lak of bubbles in the left atrium onfirms the presene of a losed foramen. (E) The atheter is shifted through the septum through a patent foramen ovale (PFO). (F) Tenting of the septum aused by stable ontat of the transseptal dilator/needle. LA, left atrium; RA: right atrium. on 18 Otober 2018 by guest. Proteted by opyright.

5 Figure 3 Closure of an atrial septal defet (ASD) under ICE guidane. (A) Colour Doppler demonstrating an ASD loated in the inferior part of the atrial septum. (B) Relation of the ASD (arrow) to intraardia strutures. (C) Positioning of the Amplatzer losure devie. (D) After several minutes, flattening of the losure devie ours. The devie is positioned stable in between the right and left atria. Ao, aorta; LA, left atrium; RA, right atrium; RV, right ventrile. presene of ommon ostia and of additional PVs, whih may influene the ablation strategy in anatomial based isolation proedures 13 (fig 4A, B). Furthermore, ICE an be used to guide ablation atheters. In order to deliver optimal radiofrequeny energy to the tissue, with a minimum amount of heat loss, a firm ontat of the atheter tip with the myoardium must be established. It has been demonstrated that ICE an ensure adequate atheter tip tissue ontat in order to ahieve transmural ablative lesions 14 and that the use of ICE improves the outome. 15 Another advantage of the use of ICE during these proedures is the ability to monitor the ourrene of aute ompliations. Potential ompliations of ablation at the site of the PVs are: PV stenosis, thromboemboli ompliations, and perforation with periardial tamponade. Visualisation of miro-bubble formation is an important harateristi aording to whih power settings of the radiofrequeny energy delivery an be adjusted, 15 to ensure maximal energy delivery at the lowest risk of PV stenosis (fig 4C). The ourrene of PV stenosis an be monitored by ICE by measuring the ostia of the PV and the systoli and diastoli flow veloities before and after atheter ablation. Both olour and pulse Doppler qualities an be used to demonstrate flow in the PV (fig 4D). Although usually inreases in PV flow veloities do not give signifiant symptoms and most patients seem to return to baseline flow harateristis within three months, ases have been reported of signifiant late PV stenosis/olusion requiring PV stenting. 16 In general, however, mild to moderate aute hanges in ostial diameters and haemodynami parameters aused by aute oedema do not seem to have signifiant impliations for the ourrene of late PV stenosis. 17 A reent report demonstrated the utility of intraardia Doppler assessment of LA ontratile funtion and reservoir funtion to predit the outome of PV isolation. 18 Finally, another important reason to onsider the use of ICE during ablation proedures in the LA is that, despite antioagulation, left atrial thrombus may our during left atrial interventional proedures, usually by attahment of thrombus material to the stable positioned transseptal sheet and/or mapping atheter. 19 Complex atrial flutter ablation Eletrophysiologial mapping under guidane of ICE has been able to identify the avo-triuspid isthmus, Eustahian ridge, and the terminal rest as anatomial barriers in atrial flutter, whih annot be visualised using fluorosopy. 20 Treatment of atrial flutter is performed by linear ablation at 985 Heart: first published as /hrt on 14 June Downloaded from on 18 Otober 2018 by guest. Proteted by opyright.

6 986 Figure 4 (A) Left PVs. There is a ommon ostium of the left PVs (diameter 2.04 m). (B) Colour Doppler in the right PVs. Three right PVs are visible. (C) Ablation atheter at ostium of the left superior PV. Note the presene of mirobubbles, indiating heat loss during ablation. (D) Pulsed wave Doppler measurements of flow in the PVs. LA, left atrium; LIPV, left inferior pulmonary vein; LSPV, left superior pulmonary vein; RA, right atrium; RSPV, right superior pulmonary vein; RMPV, right middle pulmonary vein; RIPV, right inferior pulmonary vein. Figure 5 (A) The avo-triuspid isthmus (double arrow) demonstrated with ICE as the area in between the inferior aval vein and the triuspid annulus. (B) Imaging of the avo-triuspid isthmus area in a patient with atrial flutter and Ebstein anomaly. Due to the low insertion of the triuspid valve leaflet, part of the right ventrile is inorporated in the right atrium (A indiates atrialised right ventrile). Ao, aorta; PA, pulmonary artery; Tri valve, triuspid valve; RA, right atrium; RV, right ventrile. Heart: first published as /hrt on 14 June Downloaded from on 18 Otober 2018 by guest. Proteted by opyright.

7 Figure 6 (A) Long axis view of the left ventrile (LV) and an apial LV aneurysm (aneur) in a patient with ventriular tahyardia. (B) Ablation atheter at the site of the LV aneurysm (short axis view), demonstrating perpendiular atheter tip tissue ontat. (C) Postero-basal LV aneurysm. (D) Mirobubble formation during ablation, indiating heat loss. ath tip, atheter tip. the site of the avo-triuspid isthmus, thus reating a line of lesions from the inferior aval vein towards the triuspid valve annulus (fig 5A). Stable endoardial atheter ontat an be onfirmed by ICE. 21 Next to the presene of an atrial flutter iruit based on re-entry around right sided anatomial strutures, atrial flutter based on a maro re-entrant iruit surrounding sar tissue an our for example, in patients treated for ongenital heart disease. In these patients, anomalous ardia anatomy often ompliates the treatment of atrial flutter. Partiularly in these patients, identifiation of intraardia strutures using ICE is useful. Fig 5B demonstrates the avo-triuspid isthmus area in a patient with Ebstein s anomaly. Due to the low insertion of the triuspid value leaflet, part of the right ventrile is inorporated in the right atrium (length of the atrialised ventrile 5.68 m). Ablation of ventriular tahyardia Morphologially altered myoardium for example, the presene of sar tissue or aneurysms after myoardial infartion, and multiple aneurysms as present in arrhythmogeni right ventriular dysplasia/ardiomyopathy (ARVD/ C) is prone to the formation of re-entrant iruits. The majority of ventriular tahyardias (VTs), however, are seondary to ishaemi heart disease; arrhythmias originate either from extensive sars or ishaemi border zones after infartion. The regions with sar formation are frequently akineti or dyskineti (aneurysmati), whih an easily be visualised on ICE (fig 6). Potential ompliations of VT ablations inlude thromboemboli events, valvar damage, perforation, and periardial tamponade. ICE an be used to guide atheters and for ontinuous monitoring of ompliations during VT ablation proedures The ability of phased array ICE atheters to image left sided ardia strutures with the imaging atheter exlusively in the right heart is espeially advantageous in patients with dilated ventriles, in order to evaluate the presene of intraardia thrombus, without the need of arterial or transseptal punture. Lamberti et al 24 have reported the use of ICE as an aid in establishing the position and stability of the ablation eletrode in relation to the anatomi loalisation of the VT in the LV outflow trat, thus avoiding the appliation of radiofrequeny urrent to valvar leaflets and oronary arteries. Figure 7A C demonstrates ablation of VT originating from the RV outflow trat. Furthermore, ICE an provide additional information to urrently used imaging 987 Heart: first published as /hrt on 14 June Downloaded from on 18 Otober 2018 by guest. Proteted by opyright.

8 988 Figure 7 (A) Position of atheters as seen on fluorosopy in a patient with ventriular tahyardia originating from the right ventriular outflow trat (RVOT). (B) ICE image of the same patient, demonstrating the position of the ablation atheter in the RVOT. (C) Eletro-anatomial map of the right ventrile (RV) (CARTO). The ativation of the RV is olour enoded. Red indiates the area of earliest ativation in the RVOT. (D) Imaging in a patient with ventriular tahyardia seondary to ARVD/C. An aneurysmati area was observed at the inferior part of the RV. Early fragmented signals were reorded at this site during tahyardia and subsequent radiofrequeny atheter ablation was initiated at this site. aneur, aneurysm; Ao, aorta; AP, pulmonary artery; ath tip, atheter tip; ICE, intraardia ultrasound atheter; RA, right atrium; RVA, right ventriular apex. tehniques with regard to tissue haraterisation in the diagnosis of ARVD/C 25 (fig 7D). Thus the main value of ICE for guiding VT ablation proedures is threefold: (1) identifiation of the substrate; (2) monitoring of the position of atheters in relation to ardia strutures, suh as valves and oronary arteries; and (3) diret monitoring of proedure related ompliations. Other appliations ICE an also be used as a tool to guide diagnosti evaluation of ardia masses. Using ICE, the extent of the proess, its surfae and relation to other ardia strutures an be determined. Furthermore, ICE an guide the biopsy needle and monitor aute ompliations of the biopsy, suh as perforation or bleeding. 26 Figure 8 demonstrates an example of an extensive intraardia mass. In this patient, several biopsies were obtained guided by ICE. Furthermore, initial results on the use of ICE in balloon mitral valvuloplasty, 27 LAA exlusion, 28 and visualisation of valves in the oronary sinus 29 have been reported. It is in the line of expetations that the appliations of ICE will expand in aordane with the expanding experiene with perutaneous transatheter proedures. Figure 8 (A) Evaluation of an intraardia mass by ICE. An extensive mass is present in the right atrium (RA), whih extends over the triuspid annulus to the wall of the right ventrile (RV). (B) Biopsies were taken under ICE guidane. The final diagnosis was B ell non-hodgkin lymphoma. Heart: first published as /hrt on 14 June Downloaded from on 18 Otober 2018 by guest. Proteted by opyright.

9 Table 2 Advantages of the linial use of ICE Intraardia ehoardiography (ICE): key points Aurate visualisation of intraardia anatomy that annot be visualised using fluorosopy Real time visualisation of atheters and intraardia devies Diret monitoring of proedure related ompliations Assessment of haemodynami funtion online using Doppler apaities Redution of radiation exposure for patient and operators No need for anaesthesia SUMMARY AND CONCLUSIONS With the expanding development of perutaneous interventional proedures in the atheterisation laboratory, aurate online identifiation of intraardia strutures, atheters, and devies is mandatory. At present, the image modality most ommonly used in the ath lab is fluorosopy, whih does not allow aurate evaluation of intraardia strutures. Besides TOE, ICE is at present the only imaging modality that an provide this information, ombined with haemodynami information during the proedures. ICE has several lear advantages over the use of TOE, inluding less patient disomfort and no anaesthesia, thus allowing ommuniation with the patient during the proedure. Reently ICE has been implemented in a growing number of interventional proedures. Advantages of the linial use of ICE are summarised in table 2. In onlusion, ICE is a valuable tool for guiding perutaneous interventional proedures, suh as transseptal punture and plaement of losure devies. Effiieny is improved in eletrophysiologial interventional proedures by the ability to identify anatomial strutures and integrate this information with eletrophysiologial information. Furthermore, ICE an be used as a diagnosti tool. Diret detetion of intraproedural ompliations, suh as periardial effusion and ardia tamponade, is possible with ICE, allowing immediate intervention. Integration of ICE in proedures is likely to result in redution of fluorosopy and proedure times and improved outome.... Authors affiliations M R M Jongbloed, M J Shalij, K Zeppenfeld, P V Oemrawsingh, E E van der Wall, J J Bax, Department of Cardiology, Leiden University Medial Center, Leiden, The Netherlands REFERENCES 1 Dairywala IT, Li P, Liu Z, et al. Catheter-based interventions guided solely by a new phased-array intraardia imaging atheter: in vivo experimental studies. J Am So Ehoardiogr 2002;15: Chu E, Fitzpatrik AP, Chin MC, et al. Radiofrequeny atheter ablation guided by intraardia ehoardiography. Cirulation 1994;89: Antonielli E, Pizzuti A, Palinkas A, et al. Clinial value of left atrial appendage flow for predition of long-term sinus rhythm maintenane in patients with nonvalvular atrial fibrillation. J Am Coll Cardiol 2002;39: Morton JB, Sanders P, Sparks PB, et al. Usefulness of phased-array intraardia ehoardiography for the assessment of left atrial mehanial stunning in atrial flutter and omparison with multiplane transesophageal ehoardiography. Am J Cardiol 2002;90: This paper demonstrates that phased array ICE an be a good alternative to TOE for the evaluation of left atrial mehanial funtion. 5 Thakur RK, Klein GJ, Yee R, et al. Emboli ompliations after radiofrequeny atheter ablation. Am J Cardiol 1994;74: Kok LC, Mangrum JM, Haines DE, et al. Cerebrovasular ompliation assoiated with pulmonary vein ablation. J Cardiovas Eletrophysiol 2002;13: Lundqvist C, Olsson SB, Varnauskas E. Transseptal left heart atheterization: a review of 278 studies. Clin Cardiol 1986;9:21 6. ICE is a promising tehnique to aurately visualise intraardia strutures that annot be visualised using only fluorosopy, without the need for anaesthesia Phased array ICE of the whole heart is performed via a perutaneous approah, with an ICE atheter positioned exlusively in the right atrium (RA) or right ventrile (RV) Currently, the appliation of ICE has expanded to several perutaneous interventional proedures. ICE failitates these proedures by providing online information of intraardia strutures in relation to atheters, punture needles, and devies Limitations of phased array ICE are the inability to san in a multiplane fashion and the high ost of the single use atheter The implementation of standard views of imaging planes may further expand the linial use of ICE The effet of ICE on fluorosopy and proedure times needs to be established by randomised ontrolled studies 8 Epstein LM, Smith T, TenHoff H. Nonfluorosopi transseptal atheterization: safety and effiay of intraardia ehoardiographi guidane. J Cardiovas Eletrophysiol 1998;9: Bartel T, Konorza T, Arjumand J, et al. Intraardia ehoardiography is superior to onventional monitoring for guiding devie losure of interatrial ommuniations. Cirulation 2003;107: In this study the value of ICE for guiding ASD losure is desribed and several advantages as ompared to onventional monitoring with TOE are reported. 10 Earing MG, Cabalka AK, Seward JB, et al. Intraardia ehoardiographi guidane during transatheter devie losure of atrial septal defet and patent foramen ovale. Mayo Clin Pro 2004;79: An illustrative report of the extensive experiene of the Mayo Clini with ASD losure guided by ICE. 11 Ewert P, Berger F, Daehnert I, et al. Transatheter losure of atrial septal defets without fluorosopy: feasibility of a new method. Cirulation 2000;101: Haissaguerre M, Jais P, Shah DC, et al. Spontaneous initiation of atrial fibrillation by etopi beats originating in the pulmonary veins. N Engl J Med 1998;339: Jongbloed MR, Bax JJ, Zeppenfeld K, et al. Anatomial observations of the pulmonary veins with intraardia ehoardiography and hemodynami onsequenes of narrowing of pulmonary vein ostial diameters after radiofrequeny atheter ablation of atrial fibrillation. Am J Cardiol 2004;93: Olgin JE, Kalman JM, Chin M, et al. Eletrophysiologial effets of long, linear atrial lesions plaed under intraardia ultrasound guidane. Cirulation 1997;96: Marrouhe NF, Martin DO, Wazni O, et al. Phased-array intraardia ehoardiography monitoring during pulmonary vein isolation in patients with atrial fibrillation: impat on outome and ompliations. Cirulation 2003;107: Improved outome of PV isolation guided by ICE was demonstrated in this study. The authors desribe a tehnique to adjust power settings of radiofrequeny energy guided by the visualisation of mirobubbles. 16 Ernst S, Ouyang F, Goya M, et al. Total pulmonary vein olusion as a onsequene of atheter ablation for atrial fibrillation mimiking primary lung disease. J Cardiovas Eletrophysiol 2003;14: Saad EB, Cole CR, Marrouhe NF, et al. Use of intraardia ehoardiography for predition of hroni pulmonary vein stenosis after ablation of atrial fibrillation. J Cardiovas Eletrophysiol 2002;13: In this paper assessment of PV stenosis using ICE are desribed and aute findings were ompared with omputed tomographi imaging to assess the preditive value for hroni PV stenosis. 18 Verma A, Marrouhe NF, Yamada H, et al. Usefulness of intraardia Doppler assessment of left atrial funtion immediately post-pulmonary vein antrum isolation to predit short-term reurrene of atrial fibrillation. Am J Cardiol 2004;94: This report desribes the use of ICE to measure LA appendage peak emptying veloity and peak pulmonary vein systoli wave veloity, and the use of this information to predit short term reurrene of atrial fibrillation after ablation. 19 Ren JF, Marhlinski FE, Callans DJ. Left atrial thrombus assoiated with ablation for atrial fibrillation: identifiation with intraardia ehoardiography. J Am Coll Cardiol 2004;43: Left atrial thrombus may develop during atheter ablation. The authors desribe how thrombus may be suessfully withdrawn from the LA under ICE guidane. 20 Olgin JE, Kalman JM, Fitzpatrik AP, et al. Role of right atrial endoardial strutures as barriers to ondution during human type I atrial flutter. Ativation and entrainment mapping guided by intraardia ehoardiography. Cirulation 1995;92: Heart: first published as /hrt on 14 June Downloaded from on 18 Otober 2018 by guest. Proteted by opyright.

10 990 This report desribes an eletro-anatomial orrelation of right atrial strutures involved in the atrial flutter iruit. 21 Chu E, Kalman JM, Kwasman MA, et al. Intraardia ehoardiography during radiofrequeny atheter ablation of ardia arrhythmias in humans. J Am Coll Cardiol 1994;24: Callans DJ, Ren JF, Narula N, et al. Effets of linear, irrigated-tip radiofrequeny ablation in porine healed anterior infartion. J Cardiovas Eletrophysiol 2001;12: Jongbloed MR, Bax JJ, van der Burg AE, et al. Radiofrequeny atheter ablation of ventriular tahyardia guided by intraardia ehoardiography. Eur J Ehoardiogr 2004;5: Lamberti F, Calo L, Pandozi C, et al. Radiofrequeny atheter ablation of idiopathi left ventriular outflow trat tahyardia: utility of intraardia ehoardiography. J Cardiovas Eletrophysiol 2001;12: This report desribes the appliation of ICE to guide radiofrequeny atheter ablation of ventriular tahyardia. MULTIPLE CHOICE QUESTIONS 25 Peters S, Brattstrom A, Gotting B, et al. Value of intraardia ultrasound in the diagnosis of arrhythmogeni right ventriular dysplasia-ardiomyopathy. Int J Cardiol 2002;83: Segar DS, Bourdillon PD, Elsner G, et al. Intraardia ehoardiographyguided biopsy of intraardia masses. J Am So Ehoardiogr 1995;8: Salem MI, Makaryus AN, Kort S, et al. Intraardia ehoardiography using the AuNav ultrasound atheter during perutaneous balloon mitral valvuloplasty. J Am So Ehoardiogr 2002;15: Nakai T, Lesh MD, Gerstenfeld EP, et al. Perutaneous left atrial appendage olusion (PLAATO) for preventing ardioembolism: first experiene in anine model. Cirulation 2002;105: In this report, a new promising perutaneous tehnique is desribed for olusion of the LAA, a known soure of embolism. 29 Cohen TJ, Juang G. Utility of intraardia ehoardiography to failitate transvenous oronary sinus lead plaement for biventriular ardioverterdefibrillator implantation. J Invasive Cardiol 2003;15: Eduation in Heart Interative ( There are six multiple hoie questions assoiated with eah Eduation in Heart artile (these questions have been written by the authors of the artiles). Eah artile is submitted to EBAC (European Board for Areditation in Cardiology; for 1 hour of external CPD redit. How to find the MCQs: Clik on the Online Learning: [Take interative ourse] link on the table of ontents for the issue online or on the Eduation in Heart olletion ( Free aess: This link will take you to the BMJ Publishing Group s online learning website. Your Heart Online user name and password will be reognised by this website. As a Heart subsriber you have free aess to these MCQs but you must register on the site so you an trak your learning ativity and reeive redit for ompleted ourses. How to get aess: If you have not yet ativated your Heart Online aess, please do so by visiting and entering your six digit (all numeri) ustomer number (found above your address label with your print opy). If you have any trouble ativating or using the site please ontat subsriptions@bmjgroup.om Case based Heart: You might also be interested in the interative ases published in assoiation with Heart ( Heart: first published as /hrt on 14 June Downloaded from on 18 Otober 2018 by guest. Proteted by opyright.