Carlo Di Mario, Nilesh Sutaria

Transcription

1 968 Coronary disease CORONARY ANGIOGRAPHY IN THE ANGIOPLASTY ERA: PROJECTIONS WITH A MEANING Take the online multiple hoie questions assoiated with this artile (see page 990) CATHETER See end of artile for authors affiliations Correspondene to: Professor Carlo Di Mario, Royal Brompton & Harefield NHS Trust, Sydney Street, London SW3 6NP, UK;. dimario@rbh.nthames.nhs.uk M Carlo Di Mario, Nilesh Sutaria Heart 2005; 91: doi: /hrt any textbooks, atlases, and handbooks disuss the tehniques for obtaining optimal views of all segments of the oronary arterial system. Most of these hapters, however, were written in an era when oronary surgery was the prevailing revasularisation treatment and little attention was paid to details of the lesion site and its relation with branhes. Operators and surgeons were satisfied that the oronary angiogram provided suffiient information to judge whether lesions were signifiant that is, deserving revasularisation, or non-signifiant, to be left alone and allowed visualisation of the likely site of oronary anastomosis of the bypass graft and its run-off. Perutaneous transluminal oronary angioplasty (PTCA) has now beome the dominant method for oronary revasularisation, with a ratio of PTCA: oronary artery bypass graft surgery (CABG) of between 4 8:1 in most European ountries and 2.1:1 in the UK in With the exeption of the UK, where we are still seeing new atheter laboratories being opened for purely diagnosti purposes, in the worldwide setting oronary angioplasty is arried out immediately after diagnosti angiography. Besides ost and organisational benefits, this approah offers advantages in terms of morbidity and mortality in unstable patients when rapid treatment redues the inidene of ishaemi events. 2 Under this pressure, diagnosti angiography has evolved from a standard series of 8 9 views for the left oronary artery and 2 3 views for the right oronary artery to a more foused imaging modality. Nowadays, a limited number of projetions are used to provide an overview of the status of the oronary arterial tree and to identify the ideal projetions to be used as working views for oronary angioplasty. SELECTION AND MANIPULATION: WHICH SIZE AND TECHNIQUE With improvements in atheter tehnology, 6 Frenh thin walled atheters provide equivalent or better flow rates ompared with old 7 and 8 Frenh diagnosti atheters (table 1). Satisfatory oronary opaifiation an now be ahieved with 5 Frenh and sometimes 4 Frenh diagnosti atheters. In order to inrease flow, the majority of modern diagnosti atheters no longer have a tapered tip, yet they remain safer for ostial annulation by virtue of their softer tip onstrution and smaller size. Further downsaling of atheter size is limited by the need to apply onsiderable fore during injetion to obtain optimal opaifiation, espeially of the left oronary artery. Even with a short length and large inner diameter of the onneting tubes it is not always possible to manually generate the required fore, and additionally this fore may disengage the atheter from the oronary ostium. Newly developed automati injetors with adjustable rise in injetion pressure (Aist, Brao Diagnostis) have partially solved this problem and allow the routine use of 4 or 5 Frenh diagnosti atheters with obvious advantages in terms of redued vasular damage at the atheter entry site. A small atheter size is partiularly helpful when a radial approah is used in small patients and espeially Asian female patients, beause this will minimise the risk of olusion of the radial artery and prevent arterial spasm. 3 A possible disadvantage of the disappearane of the 7 and 8 Frenh atheters is the poor torquability of modern thin walled diagnosti atheters. This has resulted in the routine use of pre-shaped atheters (Judkins, Amplatz, et) and the disappearane of tehniques using a single straight atheter (Multipurpose, Castillo, et) whih had been used in the past partiularly for the brahial approah. Interestingly, the atheter seletion and tehnique desribed below an be used not only for the femoral and left radial or brahial approah but also for the right radial/brahial approah providing that the guide wire is advaned just above the aorti valve and withdrawn with the atheter tip pointing towards the desired oronary ostium. Speially designed atheters for radial angiography, however, are oasionally helpful in simplifying annulation. 4 LEFT CORONARY ARTERY The standard atheter for imaging the left oronary artery is the 4.0 Judkins atheter in the majority of ases. Oasionally, for small females a 3.5 mm left Judkins atheter an be the first hoie. If previous investigations have demonstrated an enlarged asending aorta, a 4.5 mm or

2 Table 1 Inner lumen diameter of ommonly used diagnosti atheters (measurements provided by the manufaturers) 8 Frenh 7 Frenh 6 Frenh 5 Frenh 4 Frenh Cordis inh body inh body inh body* inh body* inh bodyà inh tip inh tip inh tip* inh tip* inh tipà inh bodyà inh tipà Boston Sientifi inh` inh` inh` Medtroni inh inh inh1 *Supertorque; ÀInfiniti; `Expo; 1Site Steer. 5.0 mm left Judkins atheter may be the preferred hoie. The optimal projetion for engaging both right and left oronary arteries is the left anterior oblique view beause this ensures that the sinus of Valsalva and asending aorta are not superimposed on either of the oronary ostia. In partiular, for the left oronary artery the use of a standard anteroposterior (AP) view or right anterior oblique view should be disouraged beause it is diffiult to appreiate the take-off of the left oronary artery inluding the presene of signifiant lesions or alifiation at the oronary ostium (fig 1). For intubation of the left oronary artery, the need for atheter manipulation is minimal. The J tipped inh or inh wire is advaned to the level of the aorti valve and the Judkins atheter tip is positioned as low as possible pointing towards the left oronary ostium. The guidewire is then withdrawn, a pressure line onneted and a test injetion performed whih normally shows the atheter to be engaged at the ostium or loated immediately below it. In the latter ase, gentle withdrawal of the atheter will allow engagement of the tip. Asking the patient to take a deep breath will failitate engagement of both oronary ostia by ensuring a more horizontal ourse to the left main and proximal right oronary arteries. If the atheter tip loops immediately in the asending aorta, one should swith early to a larger atheter (for example, 5.0 mm). When an unusual size or position of the oronary ostia is antiipated (aorti valve disease, Marfan syndrome, or ongenital heart disease) it is helpful to perform an aorti angiogram in the left anterior oblique view to guide atheter seletion. This may inlude unusual shapes suh as left Judkins 6.0 or left Amplatz 2.0 and 3.0. RIGHT CORONARY ARTERY For intubation of the right oronary artery, the preferred strategy is the use of a 4.0 right Judkins diagnosti atheter in the left anterior oblique view. The atheter must be rotated to point to the right in this view and this is best ahieved when rotation is ombined with a slow pull-bak motion of the atheter from the right oronary sinus. Breathholding in deep inspiration may failitate this manoeuvre. In 10 15% of ases, a high origin of the right oronary artery ompliates the searh for the right oronary ostium. It is often possible to obtain a semi-seletive injetion with the Judkins atheter to guide atheter seletion. If this is unsuessful, an aortogram in the left anterior oblique view may be helpful (fig 2). A multi-purpose atheter should be used for a downward direted right oronary artery and Amplatz right 2 or Amplatz left 1 or 2 in patients with dilatation of the oronary sinus and asending aorta. Careful review of the images should be performed before ompleting the angiographi examination. This will avoid missing ases suh as a separate origin from the aorta, a onus branh providing ollaterals to oluded arteries, or an abnormal origin of the left irumflex artery from the proximal right oronary artery the most frequent oronary anomaly. 5 PROBLEMS AND PITFALLS In the approah to the left oronary artery, the main onern is the presene of ostial left main stem disease. A redution in pressure with ventriularisation (low diastoli values) of the pressure wave form indiates that the atheter is obstrutive. This may be aused by the presene of a true ostial stenosis or by a small oronary ostium ourring in a hypoplasti left oronary system or in a patient with small body weight suh as Asian females. Additionally, it may result from deep engagement of the atheter tip beyond the left main into the ostium of the left anterior desending (LAD) oronary artery or left irumflex artery. This is more likely to our when the left main stem is very short, or the two arteries originate diretly from the aorta. Coronary artery spasm an always be generated by atheter engagement. The problem of spasm is more frequent at the ostium of the right oronary artery where the atheter is almost always damping pressure if the artery is nondominant. Pressure damping is also enountered in small patients despite having normal dominant arteries and using 5 Frenh diagnosti atheters. Furthermore, a deep sudden engagement of the proximal oronary artery may eliit severe ostial spasm. The areful injetion of a small amount of isosorbide dinitrate ( mg) or glyeryl trinitrate (1 2 mg) helps in the differential diagnosis. Every ase of pressure damping should be managed arefully, with prompt atheter withdrawal if needed. For example, it is imperative to avoid leaving ontrast opaifying the onus branh of the right oronary artery beause of the risk of triggering ventriular fibrillation. ANGIOGRAPHIC VIEWS FOR THE LEFT CORONARY ARTERY Table 2 lists the angiographi projetions and optimal visualisation of the left and right oronary segments. LEFT CAUDAL VIEW The so-alled spider view (fig 3B) has the main advantage of displaying the bifuration of the left main stem into the LAD and left irumflex arteries (or trifuration if an intermediate artery is present). For this reason, it seems sensible to use the left audal view as the first projetion to exlude the most fearsome of oronary lesions whih still demand surgial intervention in most ases. A more horizontal or vertial axis of the heart will require steeper (inreased audal) or more lateral spider views, but in general the inlination varies between audal and to the left. It should be noted that in the left audal projetion x ray penetration will be limited. This is a problem in obese patients where images are suboptimal and often 969

3 970 Figure 1 (A) Left anterior oblique, 30 audal. The image is learly inadequate for visualising the stenosis at the bifuration of the mid left anterior desending oronary artery (LAD) and seond diagonal branh. Note that the image optimally displays the bifuration of the LAD and left irumflex, but the shaft of the left main stem is foreshortened and the left main ostium is partially hidden by the oronary sinus. (B) 10 right anterior, 42 ranial view. The image optimally elongates the proximal and mid segments of the LAD and offers the best working projetion for treatment of the bifuration lesion. Note the improved elongation of the left main shaft and optimal delineation of the left main ostium while at the left main bifuration the two branhes are ompletely superimposed. (C) 40 left anterior oblique, 35 ranial view. Despite the obvious foreshortening and superimposition of the sinus of Valsalva on the proximal LAD, this image offers the best view of the stenosis distal to the bifuration of the mid LAD (arrow). have a grainy appearane, partiularly with old angiographi equipment. It is rarely possible to use this view as a routine working projetion for angioplasty, with the exeption of wiring of the left irumflex and left anterior desending (LAD) oronary arteries if they lie partially superimposed in the right audal views and, oasionally, during wiring of proximal diagonal branhes. The LAD is greatly foreshortened in the mid segment in this view, but stenosis of the proximal segment or of the ostium of the first diagonal branh is often optimally visualised. The left irumflex artery, in ontrast, is optimally displayed in its proximal and mid segments while ranial views are generally more helpful in elongating the more distal branhes. RIGHT CAUDAL VIEWS The lassial view uses a angulation to the right. However, an easier working projetion with less respiratory movement involves the use of redued angulation to the right (10 20 ) whih provides an optimal image even with relatively skewed audal angulation (30 40 ) (fig 3A). The degree of audal angulation is determined by the angle required to open the LAD and left irumflex artery and to obtain an optimal image of the proximal and mid segments of the left irumflex artery and the bifuration of its marginal branhes. The right audal view is of limited value for imaging the proximal and mid LAD beause of the frequent superimposition of diagonal and septal branhes, but remains the most important view for the distal LAD and should be used to measure the TIMI (thrombolysis in myoardial infartion) frame ount when required. Oasionally, ostial lesions of the LAD or intermediate branh are better demonstrated in this view than in the spider view. RIGHT CRANIAL AND ANTEROPOSTERIOR CRANIAL VIEWS If the right audal view is the usual working projetion for the left irumflex and intermediate arteries, the AP ranial view is the ideal working projetion for most lesions of the proximal and mid LAD. Although in the past the ranial view was obtained with a 30 angulation to the right, this has the disadvantage of greater superimposition of the diagonal branhes and of an uneven bakground, with wide exursion of the diaphragm during respiration when used as working projetion during angioplasty. It is therefore onventional to Figure 2 (A) Repeated attempts at annulating the right oronary artery were unsuessful and failed to visualise the ostium even with a large injetion through the right Judkins atheter low in the right oronary sinus. An aortogram is performed in a 60 left anterior oblique view. The high posterior origin of the right oronary artery (arrows) is partially delineated failitating the subsequent atheter seletion. (B) A 5 Frenh multipurpose atheter is used to annulate seletively the right oronary artery in the same view, showing a severe stenosis of the mid segment (arrow).

4 Table 2 Angiographi projetions and optimal visualisation of left and right oronary artery segments Coronary artery segment LAO 40 50, audal (spider) AP/RAO 5 15, audal 30 RAO 30 45, audal work in a more skewed ranial view (40 or more). This manoeuvre separates the proximal and mid LAD from the diagonal branhes whih run to the right and septal branhes whih run to the left of the sreen, while a possible superimposition remains only with the irumflex artery in the proximal segment. It is often neessary to inorporate a 5 10 tilt to the right to avoid superimposition of the atheter and the vertebral spine on to the LAD. The insertion of a filter wedge to over the right upper field of the image is required to obtain better ontrast definition. Although the ostia of the diagonal branhes are often better delineated in left ranial or left audal views, the AP ranial view is the most useful AP/RAO 5 10, ranial LAO 30 45, ranial Lateral audoranial LAO LM ostium LM bifuration LAD proximal LAD mid LAD distal LAD/diagonal LCX proximal LCX distal OM bifuration RCA proximal RCA mid RCA distal/rux PDA PLV LIMA anastomosis RAO View not reommended; + oasionally useful; ++ very useful; +++ ideal view. AP, anteroposterior; LAD, left anterior desending; LAO, left anterior oblique; LCX, left irumflex; LIMA, left internal mammary; OM, obtuse marginal; PDA, posterior desending artery; PLV, posterior left ventriular; RAO, right anterior oblique; RCA, right oronary artery. working projetion for angioplasty beause treatment an ontinue in this view without breathholding, whih is often required for the left ranial view in heavy patients and with suboptimal equipment. The segments whih are foreshortened in the AP ranial view inlude the distal LAD and the proximal left irumflex artery. Interestingly, this view is also ideal for elongating the distal posterolateral branhes of the left irumflex artery. LEFT CRANIAL VIEW This view is used to straighten the proximal and mid LAD and delineate its relation with septal branhes whih arise at Figure 3 (A) 15 right anterior oblique, 30 audal view. The improved fluorosopi quality, smaller respiratory exursion, and redued operator irradiation makes this view the preferred working projetion for angioplasty of this lesion of intermediate severity of the distal left main/ostial LAD (arrow). (B) 45 left anterior oblique, 35 audal view ( spider ). This view offers the greatest separation of LAD, intermediate, and left irumflex arteries. (C, D) As always, in the ase of lesions of intermediate severity, a funtional assessment is performed using a RADI pressure wire. After 86 mg of adenosine a frational flow reserve of 0.89 is reorded in the left irumflex artery (C), refleting the severity of the distal left main stenosis, and of 0.82 in the LAD (D), refleting the severity of both the left main and ostial LAD stenosis. No intervention is required. 971

5 972 an aute angle to the left of the main vessel and diagonal branhes running to the right. The LAD is further elongated by asking the patient to take a deep breath and maintain breath-holding during injetion. This manoeuvre is also important for moving the diaphragm out of the field in this view. Visualisation may be suboptimal if the LAD lies on the spine so that, espeially in obese patients, it may be neessary to inrease the left angulation to ompared with the usual The ranial angulation varies aording to the position of the heart in the hest and it is not unusual for vertial hearts to be optimally imaged with skewed views at ranial. The ranial projetion also offers optimal views of the mid and distal segments of the left irumflex artery, partiularly in the presene of a dominant left irumflex system. If the previous views have optimally shown the distal LAD and irumflex, attention an be foused on the proximal segments using a m (5 inh) field of view. Obviously, panning will be required to follow the distal vessel. If the table movements during panning are smooth, the system an automatially adjust to the hanges in bakground and maintain optimal quality. LATERAL VIEW This view is far from standard in modern oronary angiography. One pratial reason is that the lateral view requires positioning of the hands above the head to avoid superimposition of the patient s arms. This is a onstrained position for the patient whih annot be omfortably maintained for long angioplasty proedures and often interferes with intravenous infusions. The main reason, however, is that the additional information gained from this view is minimal. The lateral view provides optimal visualisation only of the mid LAD and distal LAD around the apex information whih is at most omplementary to the right audal views. Oasionally, however, eentri short lesions of the proximal and mid segment of the LAD might be obsured by septal or diagonal branhes in all the onventional previously desribed views and an be better visualised in the lateral projetion, often using variable ranial or audal angulation to eliminate superimposition from the diagnosti atheter and side branhes. It should be noted that if the artery of interest is anterior in the hest (for example, the distal LAD territory), then there is no requirement for the patient to move to an unomfortable position with the hands beneath the head. This advie is partiularly useful during visualisation of the distal anastomosis of the internal mammary artery where movement of the patient an dislodge the atheter from the mammary ostium or make seletive annulation more diffiult. In ases where redued ontrast density in other views suggests the presene of an eentri stenosis at the anastomosis of the left internal mammary artery, the lateral view should be performed with slight adjustment in the ranial-audal angulation to optimise the visualisation of this ritial segment and avoid any superimposition. Note that the lateral view is also ideal for exluding adhesion of the left internal mammary to the sternum, a ondition whih may inrease the risk of re-intervention via a median sternotomy. Oasionally, the severity of an eentri lesion of the left irumflex artery may be larified in the lateral view. RIGHT CORONARY ARTERY The right oronary artery has fewer branhes in the first, seond, and third segment (from the ostium to the rux ordis) and often two views (left anterior and right anterior) are adequate to identify all stenoses, inluding eentri lesions (fig 4, table 2). The lateral view may be ideal for assessment of the mid segment of the artery and is oasionally used as a working projetion for olusions in this segment or stent positioning. A problem with these standard views is the diffiulty in interpretation of stenoses at the rux ordis or at the ostia of the posterior desending artery (PDA) and posterolateral branhes, espeially in the presene of a very well developed (hyperdominant) right oronary artery. Cranial angulation (30 ) in the left anterior view usually solves these diagnosti questions. Many operators prefer to use a ranial (30 ) AP projetion as a routine view for the right oronary artery sine this learly delineates the region of the rux ordis and lesions of the posterior desending artery or posterolateral branhes. Additionally, the AP ranial view is a more suitable working projetion for angioplasty (fig 4C). WHICH VIEWS SHOULD BE STANDARD? The onventional approah to diagnosti angiography has been the use of a rigid sequene of multiple standard views. This often inludes standard AP, right and left anterior oblique views without ranial or audal angulation for the Figure 4 (A) 50 left anterior oblique view showing a 50% stenosis of the seond segment of the right oronary artery (arrow). (B) 30 right anterior oblique view offering a omplementary assessment of the severity of this eentri lesion. Note that in this view the long posterior desending artery (PDA) is also well visualised at the bottom of the image with all septal branhes pointing upwards. (C) 30 ranial anteroposterior view. Although this view oneals the stenosis of the mid segment of the right oronary artery, it offers exellent visualisation of the ostium of the right oronary, of the bifuration of the PDA, and of the posterior left ventriular branh whih, in this ase, has a subolusive stenosis (arrow).

6 Figure 5 (A) 10 right anterior 30 audal view. Injetion of the left oronary artery shows a long left main stem with no visible irumflex and a moderate restenosis of the mid segment of the LAD. (B) In the same view ontrast is injeted simultaneously through the right and the left oronary arteries showing well developed ollaterals from the right oronary to the mid distal left irumflex, identifying the site of origin of the irumflex and allowing measurement of the short segment of olusion. (C) Final result after angioplasty in the same view showing omplete reanalisation of the irumflex artery using a 3.5 mm drug eluting stent. left and right oronary arteries. The modern approah requires immediate interpretation of the first angiographi images and interative deision making guided by the question: did I see enough that is, have I onfirmed or ruled out the severity of all the individual lesions visualised and their relationship with side branhes? The mature operator should be aware of the angioplasty possibilities and tehniques and visualise the lesion in the most appropriate working projetions for angioplasty. New projetions should be used only when they are likely to offer additional important information, bearing in mind the radiation dose and ontrast volume. In pratie, this means that only three to four angiographi skewed views will be suffiient for the left oronary system in most ases and two to three views (or sometimes one if non-dominant) for the right oronary artery. Rotational x ray oronary angiography is a promising new development whih may ompletely hange our tehnique of image aquisition. This method has been shown to redue exposure to radiation and ontrast and to offer omparable diagnosti auray. 6 The urrently available systems, however, an rotate only in a single plane (either transverse or sagittal). Rotational angiography will possibly replae the use of single plane aquisitions when the ombined rotation in two planes will allow inlusion of most of the skewed audoranial views desribed above. HOW LONG SHOULD THE INJECTION BE? It is very important that the injetion of ontrast is delayed until fluorosopy ommenes in order to identify alifiation or staining of ontrast. The aquisition should ontinue until the ontrast has leared from the arterial tree. Slightly longer aquisition times are needed for TIMI frame ount before and after treatment in primary angioplasty or for thrombus ontaining lesions. An important determinant of the length of injetion is the need to visualise ollaterals for oluded vessels. This also requires adjustment of the view to inlude the reipient vessel in the image for example, showing the anterior wall and the mid distal LAD in the right anterior oblique view during injetion of the right oronary artery. It is often valuable to image the oluded artery through both anterograde injetion and retrograde injetion of ollaterals in exatly the same view and in the same phase of respiration. For example, in the irumstane of an oluded right oronary artery, injetion of the left oronary artery in the LAO view during deep inspiration opaifies the distal right oronary artery. A prolonged aquisition an allow an assessment of the length of the oluded segment by omparing this image with the image obtained after injetion at the right oronary artery in the same view. Obviously, the ideal way to study olusions in the presene of well developed ollaterals from the ontralateral artery is to perform a bilateral injetion (fig 5). However, a double arterial punture limits this approah whih most operators would reserve to the time of angioplasty. VENOUS BYPASS GRAFTS AND LEFT INTERNAL MAMMARY ARTERY The optimal study of patients who have undergone oronary bypass surgery begins with a areful review of the operative and prior atheterisation reords. The number of aorti anastomoses, the presene of sequential grafts, and a desription of the quality of the arteries downstream must be arefully onsidered at the time of angiography to avoid wasting time searhing for non-existent grafts. One possible approah an be to drag the right Judkins atheter along the right profile of the asending aorta in the left anterior oblique view from the right oronary ostium. Aorti anastomoses of radial arteries or venous grafts, even if not indiated by radioopaque markers at the time of the operation, an often be visualised in this view a few entimetres above the ostium of the right oronary artery. Although the position and diretion of the aorti anastomoses is influened by the surgial tehnique, in general the anastomosis for the right oronary artery tends to be the lowest and has a more vertial origin from the aorta. Seletive annulation of the right oronary graft may require a multipurpose atheter, forming a hook against the aorti valve and then withdrawing and rotating the atheter to annulate the graft seletively. Grafts for the marginal or diagonal branhes are more diffiult to visualise and often require rotation with the atheter pointing in an anterior or posterior diretion to engage the ostium. A longer atheter tip (for example, Amplatz right 1, or left 1 and 2) an often be 973

7 974 useful for diffiult grafts. Rather than using large quantities of ontrast for loation of the ostia, it an be ost effetive to perform an aortogram with the atheter slightly above the usual position against the valve that is, immediately above the level of the right oronary artery. The aortogram will larify at least the number of open grafts with the possible exeption of grafts with extremely slow flow. These grafts, however, are often identified by the presene of ontrast staining in ases of reent olusion. Please note that the injetion of small vein grafts (for example, diagonal or marginal branhes) should be performed autiously. If the assistant ontinues injeting for a prolonged period while following the graft from the ostium to the distal end, espeially in the presene of flow limitation due to the atheter at the ostium, malignant arrhythmias may develop. INTERNAL MAMMARY ARTERY The use of the left internal mammary artery (LIMA) has been standard pratie for the last years, so that most patients after bypass surgery require the evaluation of these grafts, by far the most important in terms of prognosis. The origin of the sublavian artery an be most easily engaged in a left anterior oblique view (40 60 ) and the use of a gentle 5 Frenh diagnosti atheter is unlikely to damage even a alified aorta or ostia of the ranial vessels. Oasionally, a non-seletive injetion at the ostium of the left sublavian or innominate artery an be useful when important tortuosity or narrowing of these vessels are expeted. One the right oronary artery or LIMA atheter are positioned at the ostium of the left sublavian artery, it is worthwhile rotating the x ray gantry to an AP or a slightly right anterior oblique angulation to define the origin of the internal mammary from the sublavian artery. In older patients with alifiation and tortuosity, a inh J tipped guide wire should be used to lead the diagnosti atheter in order to minimise trauma. It is not suffiient merely to onfirm pateny. The injetion should offer omplete visualisation beause the presene of distal stenoses (anastomoti or in the distal native vessels) needs to be exluded and ollaterals for other oluded vessels must be visualised. The seletive visualisation of the mammary artery is more easily ahieved with a speially designed LIMA atheter whih has a longer tip than the lassial right Judkins atheter. However, the presene of severe tortuosity of the proximal sublavian an make manipulation of the LIMA atheter very diffiult. Oasionally, other types of LIMA atheter with a hook like shape (Bartorelli, et) an be helpful, espeially if the LIMA atheter tends to have an exessive horizontal orientation when withdrawn around the urve of the sublavian artery. The alternative approah of injetion through slightly larger atheters (6 Frenh large lumen diagnosti) or with the use of power injetors, possibly ombined with olusion of the brahial artery with a pressure uff, an oasionally avoid the risks of a true superseletive injetion of the LIMA in very tortuous and frail sublavian vessels. Please note the importane of heking arefully for a normal pressure trae to exlude wedging of the atheter against the vessel wall before any injetion, inluding test injetions. In the most omplex ases steerable wires (Whooley) an be used to engage the ostium of the LIMA, with the atheter subsequently advaned over the wire. This manoeuvre, however, has an inherent risk of ostial damage. A left radial approah is oasionally the only and often the safest solution if multiple attempts from the groin remain unsuessful. The problems beome more diffiult to overome for the right internal mammary artery beause of the more tortuous ourse from the asending aorta. Sine in most ases a LIMA will also be present, the right radial approah unfortunately annot be used for visualisation of both mammaries, although some operators report high suess with tehniques for visualisation of the LIMA from the right radial approah. 7 In the ase of the right internal mammary, the same priniples of annulation of the left sublavian artery are applied with greater are to avoid trauma to the right ommon arotid artery. Regarding oronary views, for both grafts and mammary arteries the optimal projetions are similar to the projetions reommended for the native arteries to whih the grafts are anastomosed. We will therefore require an AP ranial view or right ranial view for the mid LAD, a right audal view to visualise the distal LAD, a lateral view or a spider view for better visualisation of the distal anastomosis and to exlude adhesion of the left internal mammary to the sternum. For anastomosis to posterolateral or diagonal branhes, right ranial views offer an optimal elongation of the vessel and visualisation of the distal branhes. For right oronary artery grafts often anastomosed to the PDA or posterolateral branhes of the right oronary artery, or both, it is neessary to open the distal right oronary artery bifuration using AP ranial or left ranial views. The right gastroepiploi artery (GEA) has been used as a onduit for bypass surgery, usually when mammary and saphenous vein grafts are unavailable. Angiography of this vessel is performed by first entering the ommon hepati artery using a obra atheter. The operator then advanes a torquable hydrophili guidewire to the gastroduodenal artery and then to the right GEA. Exhanging the obra atheter for a multipurpose or right Judkins will permit seletive angiography of the right GEA. LEFT VENTRICULOGRAPHY The injetion of the left ventrile during oronary angiography has been onsidered an integral part of the examination. Many non-invasive tehniques an provide similar or superior definition of the left ventriular avity volume and global and regional wall motion, with the advantage that most of them an also dynamially study wall thikness and tissue harateristis (ehoardiography, magneti resonane imaging). In my experiene, however, few patients will arrive at the atheter laboratory with a full reent report of one of suh non-invasive tehniques, despite their wide availability. Although this obviously demands better organisation of ativities and a more logial sequene of non-invasive and invasive tests, a pratial approah is to perform left ventriulography in these irumstanes unless it is felt that the exess ontrast load ould jeopardise renal funtion, espeially if angioplasty has to follow. This pragmati approah also inludes a deision regarding the number of views of the left ventrile to be aquired. When biplane systems were a standard in atheterisation laboratories, this was obviously not relevant and a right anterior oblique and left anterior oblique view were routinely obtained. Nowadays, biplane systems are rarely used. They offer limited advantages for oronary angiography and angioplasty sine a muh smaller number of views is required, and preferene is given to very skewed views whih are diffiult to obtain with a biplane system. The right

8 Figure 6 Angiographi result following an injetion of 25 ml of ontrast, injeted at 18 ml/s, with a pigtail atheter positioned immediately above the renal artery origin in an 8 left anterior oblique view. This identified a severe ostial stenosis of the right renal artery (arrow). This additional information allowed a more omplete treatment of this 76 year old patient undergoing oronary angiography beause of unstable angina but with a history of hypertension refratory to treatment, raised reatinine, and reurrent episodes of pulmonary oedema. anterior oblique view should be onsidered the standard for left ventriulography. Inorporation of a left anterior oblique view an be onsidered in those ases where eluidation of the funtion of the posterolateral wall, most often supplied by the left irumflex artery, is of paramount importane for linial deision making. Note that moderate ranial angulation an failitate better detetion of mitral regurgitation and regional wall motion. EXTRACARDIAC ANGIOGRAPHY DURING CORONARY ARTERIOGRAPHY While we reommend fousing on limited views of the oronary arteries for deiding the need and type of treatment, it seems ontraditory to disuss prolongation of the angiographi examination and the use of inreased ontrast and radiation doses for extraardia imaging. Unfortunately, patients with oronary artery disease often have atheroslerosis affeting other large vessels whih greatly influenes their long term prognosis and may modify the therapeuti approah for treatment of their oronary artery disease. For example, the presene of severe arotid stenosis, espeially if bilateral, may onstitute a ontraindiation to on-pump bypass surgery and require a staged approah with arotid stenting or endarteretomy followed by oronary surgery. The presene of a sublavian stenosis is an obvious ontraindiation to the use of the LIMA as a pedile graft and should be exluded before the intervention. The presene of a severe stenosis of a renal artery may be responsible for hypertensive attaks with pulmonary oedema and resistane to multi-drug treatment. The use of drugs widely reommended for oronary artery disease suh as angiotensin onverting enzyme (ACE) inhibitors might be ontraindiated in the presene of bilateral renal artery stenosis. When linial history or previous non-invasive tests learly suggest that one of these important vasular territories are involved it may be wise to omplete the diagnosti angiogram with a seletive injetion or an aortogram. A small movement of the table in a audal diretion is often suffiient during injetion in the asending aorta to visualise the ostia of the head vessels without the need for additional ontrast. A seletive injetion of the left sublavian artery with the atheter advaned to the ostium is normally suffiient to rule out the presene of signifiant sublavian stenoses. If a moderate narrowing is deteted, advaning the atheter over the wire to injet the mammary artery seletively will onfirm the presene of a signifiant stenosis by measuring the trans-stenoti pressure gradient. For arotid angiography, the 23 inh or 25 inh field of view (the largest normally available on a oronary angiographi system) is more than adequate for visualisation of the arotid artery from the ostium to the bifuration. In the absene of digital subtration angiography, best results are obtained with the diagnosti atheter seletively advaned to the ostium of the right ommon arotid artery or the left ommon arotid artery. In general, the very gentle 5 Frenh diagnosti atheters used nowadays (right Judkins or right Amplatz) are very unlikely to indue damage to the vessel ostium if are is taken to avoid advaning against resistane and by ensuring pressure damping is absent before injetion, inluding hand tests. Separating the arotid bifuration requires that the patient s nek is kept extended, removing the pillows under the head, and possibly plaing a small pillow under the patient s nek with the patient looking straight up at the eiling. The x ray tube is moved to an oblique left or right anterior view to obtain optimal opening of the arotid bifuration, heked with small test injetions. The use of truly iso-osmolar ontrast agents, suh as the dimer iodixanol, redues patient disomfort during all peripheral injetions. For renal artery stenoses, it is often suffiient to perform an aortogram of the desending aorta with the pigtail atheter Coronary angiography in the angioplasty era: key points Early and orret seletion of atheter size and shape is important for patient safety and to minimise proedure time, radiation exposure, and ontrast load Modern diagnosti oronary angiography should be foused on providing optimal information for linial deision making and planning oronary angioplasty The diagnosti oronary angiogram should inorporate a limited number of arefully seleted views. This demands a full understanding of the advantages and limitations of different projetions for eah speifi oronary segment Image aquisition by standard left anterior oblique and right anterior oblique projetions is useless for routine imaging of the left oronary artery and should be substituted by steep ranial or audal angulations Left ventriulography provides additional, not indispensable, but often valuable information onerning left ventriular funtion, regional wall motion, and mitral regurgitation Diagnosti angiography provides an opportunity to investigate widespread arterial disease inluding the diseases of the aorta, arotids, sublavian, and renal arteries 975

9 976 positioned at the level of the first lumbar spine, learly above the position of the ontrast inside the kidneys (fig 6). Besides opaifiation of the renal arteries, information is gathered on the status of the aorti wall, and presene of aorti aneurysms or severe pathology of the ilia arteries. Oasionally, seletive injetion via a right Judkins atheter is required, often offering the advantage of diret measurement of the transstenoti gradient sine the tip often falls beyond the ostial stenosis. Slight angulation to the left (5 10 ) may avoid superimposition of the aorta on the renal ostium. FUTURE PERSPECTIVE Conventional oronary angiography is urrently the gold standard tehnique for evaluation of patients with suspeted oronary artery disease and for defining oronary anatomy before revasularisation. However, rapid improvements in image quality and resolution have made 64 multislie tomography a powerful ompetitor to oronary angiography. The data available for 16 multislie tomography already indiates a sensitivity and speifiity of 95% and 98%, respetively, for the detetion of. 50% stenosis in patients with atypial hest pain or stable angina ompared with oronary angiography. 8 It is likely that these non-invasive tehniques will take over the diagnosti role of oronary angiography. Initially, this will inlude the exlusion of signifiant oronary artery stenoses in patients requiring valve surgery, in those with dilated ardiomyopathy, or in patients with atypial hest pain and equivoal non-invasive tests. Coronary angiography will then beome inreasingly a preliminary evaluation before perutaneous revasularisation. Coronary angiography in the UK and many other ountries is an essential part of the training programme for all future ardiologists; this pratie might hange in the near future due to the ombined effets of the growth of noninvasive imaging and the diffusion of follow on angioplasty.... Authors affiliations C Di Mario, N Sutaria, Royal Brompton Hospital, London, UK REFERENCES 1 British Cardia Intervention Soiety. British Cardia Intervention Soiety audit data London: BCIS, Spaek R, Widimsky P, Straka Z, et al. Value of first day angiography/ angioloasty in evolving non-st segment elevation myoardial infartion: an open multienter randomised trial. The VINO study. Eur Heart J 2002;23: Kiemeneij F, Laarman G. Transradial artery oronary angioplasty. Am Heart J 1995;129: Ikari Y, Ohial M, Hangaishi M, et al. Novel guide atheter for left oronary intervention via a right upper limb approah. Cathet Cardiovas Diagn 1998;44: Angelini P, Velaso JA, Flamm S. Coronary anomalies: inidene, pathophysiology, and linial relevane. Cirulation 2002;105: Raman S, Mortford R, Neff M. Rotational x-ray angiography. Catheter Cardiovas Interv 2004;63: Cha KS, Kim MH. Feasibility and safety of onomitant left internal mammary arteriography at the setting of the right transradial oronary angiography. Catheter Cardiovas Interv 2002;56: Mollet N, Cademartiri F, Krestin G. Improved diagnosti auray with 16- row multi-slie omputed tomography oronary angiography. J Am Coll Cardiol 2005;45: Heart: first published as /hrt on 14 June Downloaded from on 8 July 2018 by guest. Proteted by opyright.