7 The LEIDEN convention 1R2LCx pattern Each artery arises from respective aortic sinuses- Right coronary sinus(anterior)- Left coronary sinus(left posterior)- Non-coronary sinus(right posterior)1R2LCx pattern
12 Right coronary artery 2) Atrial branches of the RCA - < 1mm SA nodal artery ( Ramus crista terminalis) – %
13 Right coronary artery 3) Right ventricular branches Acute right marginal arteryRamus crista supraterminalis (Superior septal artery) – % , males
14 Right coronary artery 4) Posterior descending artery Dominance Posterior septal branches - < 15mm5) AV nodal artery%
15 Right coronary artery6) Postero-lateral branches to the LV - Inferior wall of the LV
16 Clinical division of the RCA Proximal - Ostium to 1st main RV branchMid st RV branch to acute marginal branchDistal acute margin to the crux
17 Left coronary artery LMCA 10-15mm(upto 30mm) length & 3-6mm(upto 10mm diameter)Trifurcates in 1/3rd : Ramus intermedius/ median artery/ left diagonal artery/straight LV arteryRare variations – absent LMCA/ pentafurcation
18 Left anterior descending artery - ~ cm ; Type I (22%) , Type II & Type IIIdiagonal branches90deg bend after turning around P. conus as it gives off 2nd diagonal branchRight ventricular branches( left conal/pre-infundibular A)~ 10 septal perforating branches (40-80mm X mm) anchors the LADLAD supplies 45-55% of LV
19 LAD(contd) 1st proximal septal A is prominent (His Bundle and LBB) Myocardial bridging – % overall (28% in children)Rarely dual LADs
20 Clinical division of the LAD Proximal - Ostium to 1st major septal perforatorMid st perforator to D2 (90 degree angle)Distal D2 to end
21 Left circumflex artery ~9.3 cm long ; mmLeft atrial branchesKugel’s artery (Arteria anastomotica auricularis magna)LV branches are called the Obtuse marginal arteriesLCx supplies 15-25% of LV (40-50% in dominant LV)
25 Prognostication scores Califf scoring systemGensini scoring systemCandell-Riera scoring systemCASS investigators: - no. of vessels- no. of proximal segments- Global LV function
26 “Dominance” A misnomer giving rise to PDA, at least 1 PLV & AV nodal A (BARI classification)- 85% right dominant8% left dominant7% co-dominant(70%/ 10%/ 20% – Hurst’s THE HEART)Left dominance is 25-30% in Bi-AoVGensini GG. Coronary Arteriography. Mount Kisco,NY: Futura Publishing Co; 1975:260–274.
27 Nodal blood supplyStudies on nodal blood supply principally by James (1961) and Hutchinson( 1978)- James : SA node - RCA 55% & LCA 45%AV node- RCA 90% & LCA 10%Hutchinson : SA node - 65% & 35%AV node- 80% & 20%AV node may have dual supply in 2% cases
28 Arterial anastomosesSeen at the intracoronary/inter-coronary levels in abundance– significant in development in collaterals in CADMost abundant at the septumIntracoronary : cm X micmInter-coronary: cm X micm
29 Coronary artery variations 2 coronary artery system is a recent evolutionary acquisitionFish and amphibia – 1 coronary arteryBirds – ~ 40% have single coronary arteries.1-5% of those undergoing CAGAngelini P – Coronary artery anomalies – current clinical issues. Definition, classifications, incidence, clinical relevance and treatment guidelines. Tex Heart Inst J 2002;29:
30 Coronary artery variations Definition of a coronary artery is not based on its origin and proximal course, but by focusing on its intermediate and distal segments/ its dependent microvascular bed.Angelini P – Coronary artery anomalies – current clinical issues. Definition, classifications, incidence, clinical relevance and treatment guidelines. Tex Heart Inst J 2002;29:
31 ? Coronary artery Variation vs Anomalies A broad spectrum of variations of which some may cause adverse effectsMost of the coronary variations may have no clinical implications as can be proven by myocardial perfusion studies.The regional distribution of a coronary artery, rather than its absolute origin and characteristics.
32 Level of variables1) Ostium ) Size ) Proximal course4) Mid-course 5) Intramyocardial ramifications 6) TerminationAnomalies without a shunt:1. Abnormal number : 1/ 3/ 4 ostia2. Anomalous origin: a) Outside SOVb) Independent origin from same sinusc) Opposite sinusd) Other artery3. Myocardial bridge4. Segmental stenosis/hypoplasiaAnomalies with shunt:1) Fistula ) APOCAC. Aneurysms
33 A puzzling issue….. Proximal course of the LAD may be very different LCx may run over atrial or ventricular surface.An RCA that terminates in the AV groove well before the crux may not always be an obstruction: 7 – 10% (Grossman)Double ostia from the RCSAll 3 arteries from a single sinusOne single artery……………..and so on……
34 The most common coronary variation (Cleveland Clinic-1,26,000 patients) was separate ostia for LAD & LCX – 0.41% and 2nd commonest was LCX from RCS / RCA – 0.37%However, in another series of 1950 angiograms coronary anomalies were seen in 5.6% cases and split RCA (1.2%) was the commonest.127,000 patients (Grossman)Angelina P. Coronary artery anomalies. Philadelphia, Lippincott Williams & Wilkins, 1999.
35 1) Ostium 2) Size 3) Proximal course Level of variables1) Ostium ) Size ) Proximal course4) Mid-course 5) Intra-myocardial ramifications6) TerminationMSCT with retrospective ECG gating is now considered the gold standard for characterization of coronary anomalies.Prompt a search for underlying CHDs1) Shi H, Aschoff AJ, Brambs HJ. Multislice CT imaging of anomalous coronary arteries. Eur Radiol. 2004;14:2) Memisoglu E, Hobikoglu G, Tepe MS. Congenital coronary anomalies in adults: Comparison of anatomic course visualized by catheter angiography and electron beam CT. Catheter Cardiovasc Interv. 2005;66:34-42.
36 Abnormal position of ostia Coronary orifice below the cuspal margin:- 10% RCS15% LCSCoronaries above the sinotubular jn ~ 6% - leads to difficult cannulation, esp RCA with a high anterior ostium.
37 Abnormal number of coronary arteries Single coronary artery %, usually benignD/d- 2 separate ostia from same sinus, atresia..Course is important – in 25% a major branch crosses the infundibulum.3 coronaries -1) Separate origin of conus artery from RCS (36- 50%)2) Absent LMCA with separate ostia for LAD & LCX4 coronaries - case reportsDual LAD % (Morettin ,1976)
38 Absent LMCA~0.4%- 1 ostia at the LCS/ 2 ostia in LCS/ 1 ostia in LCS & other RCSIncreased incidence of Left dominance6% incidence of bridgingNot usually associated with CHDsSimilar incidence of atherosclerosisDifficulty in selective cannulationTopaz et al. Absent left main coronary artery: angiographic findings in 83 patients with separate ostia of the left anterior descending and circumflex arteries at the left aortic sinus.Am Heart J.1991 Aug;122(2):
39 Shepherd’s-crook RCA ~5% Acute superiorly angled take-off of the RCA from the aorta.Difficult RCA lesion angioplastyEthan Halpern. Cardiac CT . Functional anatomy.
40 Dual LAD (Duplication) ~ % of normal heartsProximal LAD (LAD proper) bifurcates early into a short and long LAD-Type I : Short LAD in AIVS, Long LAD on prox AIVS, LV side, distal AIVS-Type II : Short LAD in AIVS, Long LAD on prox AIVS, RV side, distal AIVS-Type III: Short LAD in AIVS, Long LAD intra-myocardially in septum-Type IV: Very short LAD proper and short LAD, Long LAD from RCASpindola-Franco H et al. Dual left anterior descending coronary artery: angiographic description of Important variants and surgical implications. Am Heart J 1983:105;445–55.
41 Coronary artery Ectasia 1 - 5% in angiographic series, more in males% are congenitalDialatation of a segment to at least 1.5times of the adjacent normal coronary artery.
42 Coronary venous anatomy Targeted drug deliveryRetrograde cardioplegia administrationPotential conduit to bypass cor. artery stenosisStem cell delivery to the infarcted regionAccess to LA & LV myocardium for arrythmia mapping & ablationLV epicardial pacing in CRT
45 Conventional coronary venous nomenclature Coronary sinus - Thebasian valveAnterior IV vein(Great cardiac vein) - Vieussens valves- Left marginal vein of LV- Postero-lateral LV veinMiddle cardiac veinSmall cardiac veinsSEGMENTAL CLASSIFICATIONThe highly variable existence of the conventional veins calls for segmental classification (ant, lat, post, base, mid and apex -9 segments of the LV) of coronay veins for better epicardial localization of veins for interventional electrophiography purposes.
46 Segmental venous classification Thus 9 LV venous segments are derived which when added with the conventional classification gives the best comprehensive information to place the epicardial LV leads for CRT purposes
47 Retrograde coronary venography Lateral LV wall venous branches can be profiled by individualizing the different radiological views- considering the anterior IV vein and middle cardiac vein as reference points.
48 MDCT angiogram delineating coronary veins along with arteries Before venogram for better characterisation of coronary vein variations. However additional 60ml contrast and 9-11mSv exposure.
49 Coronary Angiographic Views Cardiac Cath 1st by Werner Forssman in 19291st contrast angiography by Chavez in 1947CART 1st performed by F. Mason Sones in 1958a high-resolution image-intensifier television system with digital cineangiographic capabilities.- Radiograph tube below and Image intensifier above (Flouroscopic imaging system with C-arm)- Physiologic monitoring system, sterile supplies, resuscitation equipment, Contrast injector (3-8ml/sec) and contrast mediaXray generator, Xray tube , Image intensifier and detector, digital angio imaging.A higher angulation increases the radiation scatter.Fluoroscopy has only 1/5th rad exposure of cine angiographyNCRPM guideline: not >3 rem per 3months.. Advised safe limit is 100mrem/week for cath lab personnel.Skin and thyroid- 15rem/year, gonads, eyes, bonemarrow- 5rem/yrCxray= 3 -5 mRoentgen ( 1 R = 1 rad for skin, 1R= 4rad for bone due to more absorption)R= radiation exposure, Rad = radiation absorptioon)Rem= radiation equivalent dose in man. 1 rem= 1rad.1SV= 1J/kg=1Gy1gy=100rad1Sv= 100rem1mrem=10micSv
50 Information from a CAG: CAG helps visualization of the major epicardial arteries up to their 2nd and 3rd order branches- Coronary anatomyCharacteristics and distribution of coronary stenosisDistal vessel sizeIntracoronary thrombusIndex of coronary flowMass of myocardium servedCollateral vasculatureOptimal injection rate: 7ml (2.1ml/s) for LCA and 4.8ml (1.7ml/s) for RCA
52 Interpretation of the significance of a lumenogram Multiple projections from different angles, preferably orthogonalKnowledge of the normal calibre of major coronaries:LMCA: 4.5 ± 0.5 mmLAD: 3.7 ± 0.4 mmLCX : 3.5 ± 0.5 mm ( 4.2 mm if dominant)RCA: 3.9 ± 0.6 mm ( 2.8 mm if non-dominant)IVUSFunctional studies : FFR
53 Mistakes in CAG interpretation Inadequate number of projections usedImproper/inadequate contrast injectionSuper-selective injectionCatheter induced vasospasmCoronary artery variationsMyocardial bridgesTotal ostial occlusionsWire induced spasm (ACCORDION EFFECT)Accordion effect: A mechanical alteration in the geometry and curvature of the vessel due to straightening and shortening of the artery due to wire advancement.
55 Angiographic projections LAO and RAO views help furnish the true PA and lateral views of the heartD/A s - foreshortening- superimpositionCranial view: Image-intensifier tilted towards headCaudal view: Image-intensifier tilted towards the feet-however the optimal angiographic view varies with coronary anatomy, body habitus and location of lesion
56 Angiographic projections Kern MJ. Cardiac Catheterization Handbook. 5th edition,2011.
58 Optimal angiographic views for coronary segments Carlo Di Mario, Nilesh Sutaria. CORONARY ANGIOGRAPHY IN THE ANGIOPLASTY ERA: PROJECTIONS WITH A MEANING Heart 2005;91:968–976.
59 RAO- LCAWhen the LMCA, LAD, LCX have an initial leftward course the long axis of these arterial segments are projected away frm the image intensifier and prevent optimal visualisation in the RAO view.
79 Optimal angiographic views for coronary segments There is no single magical projection that can beapplied uniformly to all patients for visualizinga particular coronary ateryAccording to Grossman: For LCA – RAO caudal and LAO caudal for LMCA and proc LAD in orthogonal & RAO cranial and LAO cranial for mid and distal LAD in orthogonalFor RCA: LAO for proximal RCA and RAO cranial for distal, PDA, PLV and Lateral view for midCarlo Di Mario, Nilesh Sutaria. CORONARY ANGIOGRAPHY IN THE ANGIOPLASTY ERA: PROJECTIONS WITH A MEANING Heart 2005;91:968–976.
80 Panoramic coronary angiography GIORGIO TOMMASINI et al. Panoramic Coronary Angiography. JACC 31(4),March 15, 1998:871–7
81 References Hurst’s The Heart 13th Edition Braunwalds Heart Disease 9th editionGrey’s AnatomyKern’s Handbook of Interventional CatheterizationKjell C Nikus. Coronary angiography.Grossman’s Textbook of Cardiac CatheterizationCarlo Di Mario, Nilesh Sutaria. CORONARY ANGIOGRAPHY IN THE ANGIOPLASTY ERA: PROJECTIONS WITH A MEANING Heart 2005;91:968–976David M Fiss. Normal coronary anatomy and anatomic variations. Applied Radiology, Jan 2007.Horia Muresian. Coronary arterial anomalies and variations. MAEDICA. A journal of clinical Medicine,1(1), 2006.Singh et al. The coronary venous anatomy. A segmental approach to aid CRT 2005, 46(1),Shilpa Bhimali et al. A STUDY OF VARIATIONS IN CORONARY ARTERIAL SYSTEM IN CADAVERIC HUMAN HEART. World Journal of Science and Technology 2011, 1(5): ISSN: 2231 – 2587.