br determinants - heart · proximal to the occlusion), vessel tortuosity (presence ofat least one...

Br Heart3' 1993;70:126-131

Determinants of success of coronary angioplastyin patients with a chronic total occlusion: amultiple logistic regression model to improveselection of patients

Kim H Tan, Neil Sulke, Nick A Taub, Elizabeth Watts, Sheila Karani, Edgar Sowton

AbstractObjective-To study the determinants ofsuccess of coronary angioplasty inpatients with chronic total occlusions,and to formulate a multiple logisticregression model to improve selection ofpatients.Design-A retrospective analysis of clini-cal and angiographic data on a consecu-tive series ofpatients.Patients-312 patients (mean age 55,range 31 to 79 years, 86% men) whounderwent coronary angioplasty proce-dure for a chronic -total occlusionbetween 1981 and 1992.Results-Procedural success was achievedin 191 lesions (61.2%). A major compli-cation occurred in six patients (1.90!6).Multiple stepwise logistic regressionanalysis identified the presence of bridg-ing coliaterals (p < 0.001), the absence ofa tapered entry configuration (p < 0.001),estimated duration of occlusion ofgreater than three months (p = 0.001),and a vessel diameter of less than 3 mm(p = 0.003) as independent predictors ofprocedural failure. The logistic regres-sion model was used to classify patientsinto groups of high, intermediate, andlow probability of procedural successwith cut off points of 70% and 30%. Thepredictive value for procedural success(probability 70%/6) was 91% (95% confi-dence intervals (95% CI) 83% to 96%)and predictive value for procedural fail-ure (probability <30%) was 81% (95% CI64% to 92%).Conclusions-Percutaneous translumi-nal coronary angioplasty of chronic totalocclusions is associated with a low risk ofacute complication. Procedural successis influenced by easily identifiable clini-cal and angiographic features and themultiple regression model described mayhelp to improve selection of patients.

(Br Heart J 1993;70:126-13 1)

Since the introduction of percutaneous trans-luminal coronary angioplasty by Gruentzig in1978,1 the procedure has been applied toincreasingly complex lesions includingoccluded vessels.2' Coronary angioplasty ofchronic total occlusions is recognised to havea lower primary success rate ranging from53% to 73%," and contributes to the failureto achieve complete revascularisation among

many patients with multivessel disease.78Despite this relatively low initial success rate,recanalisation of chronic total occlusions bycoronary angioplasty has become an acceptedprocedure and the prevalence has increasedfrom about 2% to 10% of the total number ofcoronary angioplasties performed in largecentres.9 At present, the ability to predict thelikelihood of procedural success for aparticular lesion is poor. Various clinical andangiographic indices have been shown to berelated to procedural success rates althoughprevious reports have reached conflictingconclusions. 1012 If a statistical model thataccurately predicted probability of proceduralsuccess on the basis of simple clinical andangiographic factors was available, this wouldhave important implications for the selectionof lesions for coronary angioplasty.

This study reports on the acute successand complication rates of coronary angio-plasty of chronic total occlusions on 312consecutive patients. It also describes a mul-tiple logistic regression model incorporatingclinical and angiographic data to predictprobability of procedural success for aparticular lesion.

Patients and methodsANGIOPLASTY PROCEDURECoronary angioplasty was performed accord-ing to a previously described protocol."3 Morethan 60% of the procedures were performedby a single operator. Steerable guide wiresystems have been in use since 1984. Thetechnique used to dilate total coronary occlu-sions differed depending on the operator butessentially consisted of movable guide wiresof increasing stiffness and low profile dilata-tion balloons, which were exchanged forlarger balloons as necessary. In some cases,"balloon on the wire" or the Magnum-Meiersystem were used. 14 Axial strength andstability were improved by advancing theballoon catheter to the point of occlusion tosplint the guide wire. Deep guide catheterengagement to obtain a stable ostial positionwas often necessary for adequate support.Once the guide wire was across the occludedsegment, its intraluminal course beyond theocclusion was confirmed by either its easymanoeuvrability or antegrade contrast flowaround the guide wire. If the position was stilluncertain, contralateral angiography wasperformed by the left femoral approach.During multivessel coronary angioplasty, theoccluded vessel was usually attempted first.

Department ofCardiology, Guy'sHospital, LondonK H TanN SulkeE WattsS KaraniE SowtonDepartment of PublicHealth Medicine,United Medical andDental Schools,St Thomas's Campus,LondonN A TaubCorrespondence to:Dr K H Tan, Department ofCardiology, Guy's Hospital,St Thomas Street, LondonSE1 9RT.Accepted for publication23 February 1993

126

on June 12, 2020 by guest. Protected by copyright.

http://heart.bmj.com

/B

r Heart J: first published as 10.1136/hrt.70.2.126 on 1 A

ugust 1993. Dow

nloaded from

http://heart.bmj.com/

Determinants ofsuccess of coronary angioplasty in patients with a chronic total occlusion

PATIENTSBetween 1981 and 1992, 312 consecutivepatients underwent a first coronary angio-plasty of a chronic total occlusion at our insti-tution. Patients who had had a myocardialinfarction within two weeks of coronary

angioplasty were excluded. The decision todilate a chronically occluded lesion was basedon the expectation that restoring antegradeflow would improve ischaemic symptoms or

left ventricular function. This implied thepresence of viable myocardium, usually theresult of collaterals that are capable of main-taining tissue viability. We defined totalocclusion as 100% narrowing of luminaldiameter with absence of a visible intralumi-nal channel. This included vessels with no

opacification of the distal segment and vesselswith faint distal opacification through ante-grade or retrograde collaterals.The mean (SD) age was 55 (9) (range 31

to 79) years, and 267 (86%) were men. Themedian duration of occlusion was six months(range up to 156 months). The estimatedduration of occlusion was less than threemonths in 87 patients (28%), between threeand six months in 66 patients (21%),between six and 12 months in 66 patients(21%), more than 12 months in 62 patients(20%), and could not be established in 31patients (10%). Two hundred and fivepatients (66%) had a history of previousmyocardial infarction and 137 (44%) hadimpaired left ventricular function with an

ejection fraction of <45% assessed by con-

trast ventriculography. Twenty one patients(7%) had previous coronary artery bypassgrafting. Before intervention, 197 patients(63%) had grade III or IV angina assessed bythe Canadian Cardiovascular Society func-tional classification.'5 Multivessel coronary

angioplasty was performed in 127 patients(41%) and multilesion coronary angioplastyin 134 patients (43%). The occluded vesselwas the left anterior descending coronary

artery in 162 patients (52%), the circumflexcoronary artery in 43 (14%), the right coro-

nary artery in 100 (32%) and a saphenousvein graft in seven patients (2%). The lesionwas located in the proximal segment of thecoronary artery in 40%, the middle segmentin 48% and the distal segment in 12%.

METHODS AND DEFINITIONSThe baseline clinical characteristics on all 312patients were recorded. Details from theangiograms taken before angioplasty on 264patients (85%) were assessed by two indepen-dent observers without knowledge of proce-dural outcome. Hand held callipers were usedfor measuring distances and diameters fromthe projected angiographic film using theimage of the guide catheter to assess the scaleof magnification.The clinical indices analysed as possible

determinants of procedural success includedage, sex, angina grade, extent of coronaryartery disease, left ventricular function, esti-mated duration of occlusion, and whethermultivessel or multilesion coronary angio-

plasty was performed. The duration of occlu-sion was estimated either from the date ofmyocardial infarction in the distribution ofthe occluded vessel, abrupt worsening ofangina pectoris, or information provided bysequential angiograms. Other clinical factorsconsidered were a history of smoking, hyper-tension, diabetes mellitus, hypercholestero-laemia, previous myocardial infarction,previous coronary artery bypass surgery, andpresence of family history.The angiographic indices analysed in-

cluded location of lesion, vessel diameter,length of occlusion (estimated in 246 patientsin whom the distal extremity of the occlusioncould be defined by collateral contrast filling),morphology of the occlusion (a tapered entryconfiguration at the occlusion as opposed toan abrupt cut off), distance of the occlusionfrom the coronary orifice, the presence of dif-fuse disease (at least one stenosis of >50%proximal to the occlusion), vessel tortuosity(presence of at least one bend of >450 proxi-mal to the occlusion), calcium at the site ofthe occlusion (radio-opacity present beforecontrast injection), thrombus at the site of theocclusion (presence of intraluminal fillingdefect or contrast staining within the lumen),a side branch at the occlusion, presence ofbridging collaterals (multiple small collateralchannels bridging the angiographic gap foundoutside the perceived lumen of the vessel),and whether distal vessel opacification waspresent.

Procedural success was defined as less than50% residual diameter stenosis at the dilatedsites. A major in hospital complication wasdefined as the occurrence of either death,myocardial infarction, or emergency coronaryartery bypass grafting.

STATISTICAL METHODSContinuous variables are expressed as mean(SD) except estimated duration of occlusiondue to its highly skewed distribution. Thestudy patients were divided into subgroupsaccording to procedural outcome. The angio-graphic and clinical indices analysed as poss-ible determinants of procedural success werecompared between these patient groups.Categorical variables between patient groupswere compared with the x2 test or Fisher'sexact test and continuous variables were com-pared with the unpaired t test. The X2 test fortrend was used to test for an associationbetween time period and procedural successrate. A p value of <0 05 was considered sig-nificant. All indices found to be significantlyrelated to procedural outcome by univariateanalysis were included in a multiple logisticregression analysis. The backwards stepwiseselection procedure was used to identify inde-pendent predictors of procedural outcomesignificant at the 1% level (with BMDP pro-gram LR).'6 An equation was developed thatbest classified the chances of procedural suc-cess. The procedural success rates found wereexamined separately for patients whose pre-dicted probability of success was low (<30%),intermediate (30% to 69%), or high (> 70%).

127



/B


ugust 1993. Dow

nloaded from


Tan, Sulke, Taub, Watts, Karani, Sowton

Table 1 Clinicalfactors related to procedural outcome for all 312 patients

Procedural success Proceduralfailure(n = 191) (n = 121)n (%/6) n (%/6) p Value

Age (mean (SD)) (yr) 55 (9) 56 (10) NSMen 165 (86) 102 (84) NSAngina grade III/IV 127 (66) 70 (58) NSPrevious MI 126 (66) 79 (65) NSEF < 45% 84 (44) 55 (45) NSSmoking 115 (60) 74 (61) NSHypertension 41 (21) 33 (27) NSFamily history 84 (44) 61 (50) NSDiabetes mellitus 15 (8) 7 (6) NSHypercholesterolaemia 90 (47) 47 (39) NSPrevious CABG 12 (6) 9 (7) NSMultivessel disease 105 (55) 92 (76) p < 0 001Multivessel PTCA 80 (42) 47 (39) NSMultilesion PTCA 89 (47) 45 (37) NSDuration of occlusion 114 (64) 80 (78) p = 0-02>3 months*Lesion location:LAD 102 (53) 60 (50)CX 31 (16) 12 (10) NRCA 52 (27) 48 (40) NSSVG 6 (3) 1 (0 8)

*Available only in 281 patients.CABG, coronary artery bypass grafting; CX, circumflex coronary artery; EF, ejection fraction;LAD, left anterior descending artery; MI, myocardial infarction; PTCA, percutaneous translu-minal coronary angioplasty; RCA, right coronary artery; SVG, saphenous vein graft.

Predicted probabilities of success were esti-mated by the jacknife method to compensatefor the fact that the same data were beingused to test the prediction rule as had beenused to derive it.

ResultsACUTE RESULTSProcedural success was achieved in 191lesions (61 2%) and did not differ signifi-cantly by location of the occlusion (p = 0-06,table 1). The procedural success rate was56% for the first 104 cases, 57% for the next104 cases, and 71% for the last 104 cases(p = 0 02). The most common cause of fail-ure was inability to pass the guide wire acrossthe occlusion (96 of 121 lesions). Failure tocross the lesion or dilate it with a ballooncatheter accounted for 25 of the failures. Theprocedural success rate was highest for occlu-sions less than three months old (74%), inter-mediate for occlusions between three and 12months old (64%), and least for occlusionsgreater than 12 months old (47%).

Six patients (1 9%) had one or more majorin-hospital complications. One procedural

Table 2 Angiographic data related to procedural outcome for 264 patients

Procedural success Proceduralfailure(n = 159) (n = 105)n (%) n (%) p Value

Calcium at occlusion 24 (15) 23 (22) NSThrombus at occlusion 14 (9) 3 (3) NSTapered entry configuration 121 (76) 55 (52) < 0 001Vessel tortuosity 44 (28) 27 (26) NSSide branch at occlusion 76 (48) 67 (64) = 0 01Diffuse disease proximal 20 (13) 16 (15) NS

to occlusionVessel diameter >3 mm 95 (60) 36 (34) < 0 001Presence of distal vessel opacification 44 (28) 41 (39) NSBridging collaterals 10 (6) 41 (39) <0 001Mean (SD) distance of occlusion 33 (18) 30 (17) NS

from orifice (mm)Mean (SD) lesion length (mm)* 12 (11) 12 (8) NS

*Available only in 246 patients.

death (03%) occurred in a patient who hadan apparently uncomplicated coronary angio-plasty to the left anterior descending arteryand the right coronary artery, which waschronically occluded. He developed ST seg-ment elevation in the anterior chest leads 12hours after the procedure then recurrent ven-tricular fibrillation and failed to respond tointensive resuscitation. Five patients (1 6%)needed emergency coronary artery bypassgrafting after failure to recanalise theoccluded vessel; three had a coronary dissec-tion (left anterior descending artery in twopatients and left main coronary in one) as aresult of guide catheter or guide wire trauma,and two developed cardiac tamponade fromcoronary artery perforation. Of these, one(0-3%) also had a Q wave myocardial infarc-tion.

DETERMINANTS OF PROCEDURAL SUCCESSThe clinical characteristics (table 1) andangiographic data (table 2) were analysed toassess their association with procedural out-come. Univariate analysis of 27 clinical andangiographic factors showed that proceduraloutcome was significantly related to six vari-ables. Procedural success was less commonin patients with multivessel disease than inthose with single vessel disease (53% v 75%,p < 0001), with lesions occluded for morethan three months than those occluded forless than three months (59% v 74%, p =

0-02), with vessels less than 3 mm than thosegreater than 3 mm in diameter (48% v 73%,p < 0.001), with occlusions without a taperedentry configuration (43% v 69%, p < 0.001),with lesions with side branches (53% v 69%,p = 0-01), and with lessions with bridgingcollaterals (20% v 70%, p < 0-001).

Multiple stepwise logistic regression analy-sis identified the presence of bridging collat-erals (p < 0 001), the absence of a taperedentry configuration (p < 0-001), duration ofocclusion of more than three months(p = 0-001), and vessel diameter of <3 mm(p = 0-003) as independent predictors of pro-cedural failure (table 3). Neither of the othervariables analysed contributed significantly tothis regression model. With this model, theestimated probability of procedural success(p) is: p = eY/(1 + eY) where e = 2-72, andy = - 2 56 x bridging collaterals) + (1.29x tapered entry configuration) + (- 135 x

duration of occlusion) + (1 00 x vesseldiameter) + 0-82.

Bridging collaterals were scored 1 for pres-ence and 0 for absence; tapered entry con-figuration was scored 1 for presence and 0 forabsence; duration of occlusion was scored 1for >three months and 0 for <three months;vessel diameter was scored 1 for>3 mm and 0 for <3 mm. The estimatedprobability of procedural success from thelogistic regression model was used to classifypatients into groups of high, intermediate,and low probability of procedural successwith cut off points of 70% and 30% (table 4).With the jacknife method, the predictivevalue for procedural success (where the prob-

128



/B


ugust 1993. Dow

nloaded from



Table 3 Multiple logistic regression model to predict procedural success

Variable Coefficient SE x2 value p Value

Bridging collaterals -2-56 0-45 41-4 <0-001Tapered entry configuration 1-29 0 34 15-1 <0-001Duration of occlusion > 3 months -1-35 0 44 10-8 0-001Vessel diameter > 3 mm 1-00 0-33 9-16 0 003Constant 0-82 0-48 3-06 0-080

Analysis was based on 236 patients with complete clinical and angiographic data.

Table 4 Patients classified by observed success and predicted probability ofsuccess

Predicted probablity of success

<30% 30-69% 70% Total

Observed success 7 56 86 149Observed failure 29 49 9 87Patients (n) 36 105 95 236Predictive value for - - 91 -

procedural success (%)Predictive value for 81 -

procedural failure (%)

ability for success >70%) was 91% (95% CI83% to 96%) and predictive value for proce-dural failure (where the probability for suc-cess <30%) was 81% (95% CI 64% to 92%).One hundred and five patients (44%) had anintermediate predicted probability of success(where the probability for success was 30% to69%). Thus the model successfully identifiedtwo groups, accounting for 56% of thelesions, as having an unusually high (>70%)or low (<30%) likelihood of procedural suc-cess.

DiscussionDuring the early years of percutaneous trans-luminal coronary angioplasty, a total occlu-sion was considered an absolutecontraindication to the procedure.'7 Evidencethat left ventricular function may improveafter recanalisation of chronic totalocclusions'8 and the perception that proce-dural failure is not associated with an adverseoutcome'9 provided the impetus for itsincreasing application. In the most recentcoronary angioplasty registry report from theNational Heart, Lung, and Blood Institute,chronic total occlusions accounted for 10% ofall attempted coronary angioplasties duringthe period 1985-6.9The procedural success rate per lesion of

62 1%, mortality of 0 3%, myocardial infarc-tion rate of 0 3%, and incidence of emer-gency coronary artery bypass grafting of 1-6%in this study are comparable with previousstudies. Other studies have reported proce-dural success rates ranging from 53% to 73%depending on the inclusion criteria,4- mortal-ities from 0% to 1 - 1 %,5 12 19 myocardial infarc-tion rates from 0% to 2-1%,5620 andemergency bypass surgery rates from 0% to8-9%.5 19 20 The differences in the success ratesbetween the various studies probably reflectdifferences in the selection criteria of patientsfor coronary angioplasty of chronic total

occlusion. A lesion would have been selectedonly if the operator considered that the occlu-sion could be recanalised with a reasonablechance of success. Hence the success ratesreported may have differed if dilatations of alltotal occlusions were attempted. Althoughthe procedural success rate was lower thancoronary angioplasty of non-occluded lesions,recanalisation of chronic total occlusion wasassociated with fewer complications. This lowrisk of acute complications has also beenshown by previous studies.51219 The safety,however, is neither absolute nor a consistentfinding. The most recent report from theNational Heart, Lung, and Blood Instituteshowed a similar incidence of major compli-cations occurring during coronary angioplastyof total and sub-total occlusions.21 In ourstudy, complications often occurred directlyas a result of the procedure itself, either fromguide catheter or guide wire trauma causingcoronary dissection or perforation. The oneprocedural death was related to acute vesselclosure in a non-occluded vessel after anuncomplicated multivessel coronary angio-plasty in a patient with impaired left ventricu-lar function.An improved success rate was found with

the last 104 cases attempted in this study.Similar improvements in success rate withsubsequent attempts at dilating chronic totalocclusions have been reported by other inves-tigators.'2 This may be attributed to improvedselection of cases, improved operator experi-ence and angioplasty technique, and evolu-tion of equipment. These developmentsoccurred in parallel and it would be difficultto attribute the improved success rate to anysingle variable. Improved selection of patientsmay have arisen as a result of knowledgegained from previous published reports oncoronary angioplasty of chronic total occlu-sion. In our study, more than 60% of the pro-cedures were performed by a single operator,who also often assisted the more junior oper-ators when they failed to recanalise theoccluded artery. Therefore, the impact ofoperator experience on success rate cannot beassessed accurately. Stone et al have shownno clear correlation between the number ofdilatations of total occlusions attempted andthe procedural success rate.'2 Despite theintroduction of new angioplasty technologysuch as laser angioplasty22 and low speedrotational angioplasty,23 the approach to cor-onary angioplasty of a total occlusion hasremained essentially unchanged at our insti-tution. Most procedures in our study wereperformed with conventional systems. Thecombination of improved balloon angioplastyequipment (guide catheters with better sup-port, guide wires of varying stiffness, and lowprofile balloon catheters) and improved tech-niques (deep guide catheter engagement,advancing the balloon dilatation catheter tothe totally occluded arterial segment to splintthe guide wire) have increased the likelihoodof crossing and dilatation of the occluded seg-ment. Few cases involved the use of speciallydesigned catheters6 or the Magnum-Meier

129



/B


ugust 1993. Dow

nloaded from


Tan, Sulke, Taub, Watts, Karani, Sowton

system.14 Thus the impact of these specially dilatations in patients who had multivesseldesigned pieces of angioplasty equipment is disease and in lesions with side branchesdifficult to assess in the presented study although these factors did not reach statisticalcohort. Even with specially designed independence in the multivariate model. Thecatheters,6 the reported overall success rate presence of distal vessel opacification did notfor coronary angioplasty of total occlusion emerge as an important determinant of pro-was no higher than 73% and may not be cedural success in our study, as was shown bysuperior to conventional systems.24 Pre- some investigators.1' 12 Others, however, haveliminary results comparing the Magnum- reported conflicting results.427 The differ-Meier system with the conventional ences may be accounted for by the differenttechnique have shown contradictory results24 underlying mechanisms that have caused the25 and other new technology such as laser distal vessel opacification seen in the variousangioplasty22 and low speed rotational angio- study populations. These mechanisms in-plasty23 will need further clinical evaluation. clude spontaneous recanalisation of the

Given the increasing use of coronary angio- occlusion, subtotal occlusions, collaterals,plasty to recanalise chronic total occlusions9 and a combination of these.28and the lower primary success rate,46 the Apart from the presence of bridging collat-ability to predict accurately the likelihood of erals which reduces the overall probability ofprocedural success will have important impli- procedural success to 20%, however, thecations in selecting cases for coronary angio- presence of the other variables in isolationplasty. In this study, multiple logistic should not deter attempts to recanaliseregression analysis identified the presence of chronic occlusion. In the presence ofbridging collaterals, absence of a tapered favourable angiographic indices, even occlu-entry configuration, a longer duration of sions of over a year old can be dilated with aocclusion, and a smaller vessel diameter as procedural success rate approaching 50%independent predictors of procedural failure. with an acceptable complication rate. In thisThe influence of vessel size has not been pre- study, a model for predicting probability ofviously reported but the other indices have procedural success was developed with step-been shown to predict procedural failure in wise logistic regression analysis that com-some studies. Bridging collaterals, which rep- bined these clinical and angiographicresent dilated vasa vasorum,26 might divert variables. This model identified 56% of thethe guide wire during coronary angioplasty. lesions as having a procedural success rateAs a result of their fragility, they perforate that differed considerably from the data baseeasily if touched by a guide wire. The pres- mean of 61 2%; 95 lesions were classified asence of bridging collaterals as a predictor of having a high chance of procedural successprocedural outcome has been shown by and had an actual success rate of 91 %,some'2 but not all previous studies.51' A whereas 36 were classified as having a lowtapered entry configuration assists in guide chance of procedural success and had anwire placement thus providing guide wire actual success rate of 19%. The remainingstability, increases the chance of finding the 105 lesions that were classified as having ancorrect channel, and allows axial force to be intermediate predicted probability of proce-transmitted directly to the distal lumen. Its dural success had an actual success rate ofinfluence on procedural outcome is con- 53%.firmed by some220 but not other studies.4 5 11 Thus the described model may assist in theThe duration of occlusion may determine the selection of chronic total occlusions forhistological components of the occluded seg- potential angioplasty with those of low likeli-ment and influence the ability of a guide wire hood of success treated by an alternativeto cross the lesion. The longer the duration, mode of revascularisation.the more the lesion is organised with fibroustissue and the likelihood of recanalisation STUDY LIMITATIONSbecomes less. In some41927 but again, not all This study is a retrospective analysis of dataprevious studies,51'2 the estimated duration and is subject to the limitations inherent inof occlusion was related to procedural out- any retrospective study. The frequency ofcome. This inconsistent finding may be partly occurrence of some of the angiographicexplained by the difficulty and inherentlimi- indices analysed were low. Thrombus wastation of estimating the duration of occlusion present in only 17 and calcium in only 47 offrom clinical information. A larger vessel the 264 coronary angiograms included in thediameter may allow a greater margin of error analysis. These indices may become signifi-during the passage of the guide wire across cant determinants of procedural successif athe occluded segment into the distal intralJu- greater number of patients were available inminal course if the guide wire deviatesf ithe study. Also, although the model wasthe main vessel axis. Hence the likelihood of developed from a large data base and vali-the guide wire creating subintimal pathways date&''o the database from which it wasby getting underneath a plaque is reduced in derivedwith the jacknife method, it needs toa larger vessel as opposed to a small diameter be tested prospectively and against othervessel where a small deviation from its main populations. We are currently collecting newaxis could cause the guide wire to leave its data for this purpose.intraluminal course, create a subintimal path-way, and thereby pursue an intramural CONCLUSIONScourse. There were also more unsuccessful This study confirms previous reports that

130



/B


ugust 1993. Dow

nloaded from



coronary angioplasty of chronic total occlu-sions is associated with a low risk of acutecomplication. It has also shown that proce-dural success is adversely influenced by easilyidentifiable clinical and angiographic features.Although further prospective validation isnecessary, the multiple logistic regressionmodel described may help clinicians assessthe suitability of coronary angioplasty in indi-vidual patients with chronic total occlusions.

1 Gruentzig AR. Transluminal dilatation of coronary arterystenosis [letter]. Lancet 1978;1:263.

2 Savage R, Hollman J, Gruentzig AR, King S m, DouglasJ, Tankersley R. Can percutaneous transluminal coro-nary angioplasty be performed in patients with totalocclusion [abstract]? Circulation 1982;66(suppl II):II-330.

3 Heyndrickx GR, Serruys PW, van den Brand M,Vandormael M, Reiber JHC. Transluminal angioplastyafter mechanical recanalization in patients with chronicocclusion of coronary artery [abstract]. Circulation1982;66(suppl II):II-5.

4 Kereiakes DJ, Selmon MR, McAuley BJ, McAuley DB,Sheehan DJ, Simpson JB. Angioplasty in total coronaryartery occlusion: experience in 76 consecutive patients.J Am Coi Cardiol 1985;6:526-33.

5 Bell MR, Berger PB, Bresnahan JF, Reeder GS, BaileyKR, Holmes DR Jr. Initial and long-term outcome of354 patients after coronary balloon angioplasty of totalcoronary artery occlusions. Circulation 1992;85:1003-11.

6 Hamm CW, Kupper W, Kuck K-H, Hoffman D, BleifeldW. Recanalization of chronic, totally occluded coronaryarteries by new angioplasty systems. Am Y Cardiol1990;66:1459-63.

7 Bell MR, Bailey KR, Reeder GS, Lapeyre AC HI, HolmesDR Jr. Percutaneous transluminal coronary angioplastyin patients with multivessel disease: how important iscomplete revascularization for cardiac event-free sur-vival? JAm Coll Cardiol 1990;16:553-62.

8 Deligonul U, Vandormael MG, Kern MJ, Zelman R,Galan K, Chaitman BR. Coronary angioplasty: a thera-peutic option for symptomatic patients with two andthree vessel coronary disease. JAm Coil Cardiol 1988;11:1173-9.

9 Deitre K, Holubkov R, Kelsey S, et al. Percutaneoustransluminal coronary angioplasty in 1985-1986 and1977-1981: the National Heart, Lung, and BloodInstitute Registry. N EnglJ Med 1988;318:265-70.

10 DiSciascio G, Vetrovec GW, Cowley MJ, Wolfgang TC.Early and late outcome of percutaneous transluminalcoronary angioplasty for subacute and chronic totalcoronary occlusion. Am HeartJ 1986;111:833-9.

11 LaVeau PJ, Remetz MS, Cabin HS, Hennecken JF,McConnell SH, Rosen RE, Cleman MW. Predictors ofsuccess in percutaneous transluminal coronary angio-plasty of chronic total occlusions. Am J Cardiol 1989;64:1264-9.

12 Stone GW, Rutherford BD, McConahay DR, Johnson

131

WL Jr, Giorgi LV, Ligon RW, Hartzler GO. Proceduraloutcome of angioplasty for total coronary artery occlu-sion: an analysis of 971 lesions in 905 patients. J AmCoil Cardiol 1990;15:849-56.

13 Sowton E, Timmis AD, Crick JCP, Griffin B, Yates AK,Deverall P. Early results after percutaneous translumi-nal coronary angioplasty in 400 patients. Br Heart J1986;56:115-20.

14 Meier B, Carlier M, Finci L, Nukta E, Urban P,Niederhauser W, Favre J. Magnum wire for balloonrecanalization of chronic total coronary occlusions. AmJ Cardiol 1989;64:148-54.

15 Campeau L. Grading of angina pectoris. Circulation 1976;54:522-3.

16 Dixon WJ, Brown MB, Engeiman L, Jennrich RI. BMDPStatistical Software Manual. University of California Press1990;2:1013-45.

17 Kent KM, Bentivoglio LG, Block PC, et al. Percutaneoustransluminal coronary angioplasty: report from theRegistry of the National Heart, Lung and BloodInstitute. Am Jf Cardiol 1982;49:2001-2020.

18 Melchior JP, Doriot PA, Chatelain P, Meier B, Urban P,Finci L, Rutishauser W. Improvement of left ventricularcontraction and relaxation synchronism after recanaliza-tion of chronic total coronary occlusion by angioplasty.JAm Coll Cardiol 1987;4:763-8.

19 Melchior JP, Meier B, Urban P, Finci L, Steffenino G,Nobel J, Rutishauser W. Percutaneous transluminalcoronary angioplasty for chronic total coronary arteryocclusion. Am J Cardiol 1987;59:535-8.

20 Ivanhoe RJ, Weintraub WS, Douglas JS Jr, Lembo NJ,Furman M, Gershony G, et al. Percutaneous translumi-nal coronary angioplasty of chronic total occlusions: pri-mary success, restenosis, and long-term clinicalfollow-up. Circulation 1992;85:106-15.

21 Ruocco NA Jr, Ring ME, Holubkov R, Jacobs AK, DetreKM, Faxon DP. Results of coronary angioplasty ofchronic total occlusions (the National Heart, Lung, andBlood Institute 1985-1986 Percutaneous TransluminalAngioplasty Registry). Am J Cardiol 1992;69:69-76.

22 Cumberland DC, Belli AM, Oakley GDG, et al. "Laserwire" for percutaneous angioplasty complete peripheraland coronary arterial occlusions: initial clinical results[abstract]. JAm Coll Cardiol 1989;13:60A.

23 Kaltenbach M, Vallbracht C. Low speed rotational angio-plasty: applicability to chronic coronary artery obstruc-tions [abstract]. Circulation 1988;78(suppl II):II-83.

24 Haerer W, Schmidt A, Eggeling T, Hoher M, Kochs M,Hombach V. Angioplasty of chronic total occlusions:results of a controlled randomized trial [abstract]. J AmColl Cardiol 1991;17: 113A.

25 Meier B, Urban P, Muller T, Villavicencio R, Dorsaz P,Favre J. Randomized comparison between Magnum andstandard systems for balloon recanalisation of chronictotal coronary occlusions [abstract]. Eur Heart J 1990;11(suppl):21.

26 Barger AC, Beeuwkes R m, Lainey I1 Silverman KJ.Hypothesis: vasa vasorum and neovascularization ofhuman coronary arteries. N Engl J Med 1984;310:175-8.

27 Serruys PW, Umans V, Heyndrickx GR, van den BrandM, de Feyter PJ, Wijns W, et al. Elective PTCA oftotally occluded coronary arteries not associated withacute myocardial infarction; short-term and long-termresults. Eur HeartJ' 1985;6:2-12.

28 Meier B. Chronic total occlusions. In: Topol EJ. Textbookof interventional cardiology. Philadelphia: WB Saunders,1990:300-26.



/B


ugust 1993. Dow

nloaded from


br determinants - heart · proximal to the occlusion), vessel tortuosity (presence ofat least one...

Documents