CARDIOLOGY
`
`CLlNlCS
`
`Michael H. Crawford, MD, Consulting Editor
`
`VOLUME 7/ NUMBER 4
`NOVEMBER 1989
`
`CORONARY ANGIOPLASTY
`
`Gerald Dorros, MD, Guest Editor
`Ruben F. Lewin, MD, and
`Iames F. King, MD, Co-Guest Editors
`
`W. B. SAUNDERS COMPANY
`Harcourt Brace Jovnnovich, Inc.
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`w. B. SAUNDERS (IUMI’ANY
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`CARDIOLOCY CLINICS
`November 1989
`Volume 7~Number 4
`
`ISSN 0733—8651
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`Coronary Angioplasty
`
`0733—8651/89 $0.00 + .20
`
`Coronary Angioplasty in Patients with
`(Prior Coronary Artery Bypass Surgery:
`All Prior Coronary Artery Bypass Surgery Patients
`and Patients More than 5 Years After Coronary
`Bypass Surgery
`
`Gerald Dorms, MD,* Ruben F. Lewin, MD,T
`and Lynne M. Mathiak, RN21:
`
`MATERIALS AND METHODS
`
`Patient Selection
`
`All patients who underwent PTCA had one
`or more prior CABGs and had a significant
`coronary or vein graft stenosis(es) that produced
`severe angina or significant myocardial ische-
`mia, confirmed by noninvasive studies.
`The patient’s anatomy (that is, the site of the
`stenosis(es), determined by cineartcriograms)
`was the determinant of whether or not PTCA
`was feasible technically and his clinical condi-
`tion determined its appropriateness.
`
`Patient Evaluation
`
`Percutaneous transluminal coronary an gio—
`plasty 1PTCA} has been used successfully in
`patients who have had prior bypass surgery
`(CABS) as a means ofreyascularizing the myo-
`cardium and avoiding repeat myocardial reyas-
`cularization.2' 3' 9' “‘15- 19’ 25 Percutaneous trans-
`luminal coronary angioplasty has been effective
`for lesions in relatively new bypass grafts (3 or
`less years old), bypass grafts that are not dis-
`eased dinusely, and in patients with a relatively
`high surgical risk because of significant medical
`problems and/or diminished left ventricular
`function (left ventricular ejection fraction less
`than or equal to 40 per cent). Old saphenous
`vein grafts (greater than 5 years) have been
`considered to be a relative and/or absolute
`contraindication to PTCA because of distal
`embolizationfl' 25; in the opinion of some, PTCA
`of lesions at the aortic anastomosis or Within
`the graft shaft was relatively contraindicated
`because of the high restenosis rate.21* 25- 29 The
`first section in this article will detail our expe-
`rience with PTCA of prior CABC patients and
`the second section, with PTCA in the subset of
`patients 5 or more years after their last coronary
`bypass surgery.
`
`the “culprit” le-
`In multiple—lesion PTCA,
`sions always were considered accessible to the
`angioplasty catheter. Selected patients under-
`went PTCA of multiple lesions, despite the
`presence of significant disease in other coronary
`vessels that would not be dilated because of the
`diseases extensive and/or diffuse nature and/or
`the small caliber of the vessel. These patients
`
`
`From the Department of Cardiology, St. Luke's Medical Center, Milwaukee, Wisconsin
`
`*Interventional Cardiologist; Director, The William Dorms-Isadore Fcucr Foundation for Interventional Cardiovascular
`Disease; and Associntn Clinical Professor of Medicine (Cardiology). Medical College of Wisconsin
`Tlntnrventional Cardiologist
`iiiardiovnscular Nurse Clinician
`
`Cardiology Clinics—Vol. 7, No. 4, November 1989
`
`791
`
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`a.
`
`agemcnt if the culprit lesions were dilated suc-
`cessfully.
`Selected patients preferentially underwent
`PTCA rather than repeat CABG because of an
`anticipated prohibitively high surgical morbid—
`ity and/or mortality risk (presence of multiple
`prior CABGS; functioning internal mammary
`graft(s); concomitant severe, debilitating medi—
`cal conditions; cardiogenic shock; and/0r severe
`left ventricular dysfunction [left ventricular
`ejection fraction less than or equal to 35 per
`cent]).
`Patients were referred preferentially for
`PTCA when (1) there was a lack of obvious vein
`graft donor sources; (2) the significant lesion(s)
`was a vessel that had undergone coronary end—
`arterectomy(ies); (3) the patient had a previously
`complicated
`and
`prolonged
`postoperative
`course; or (4) he probably would require valve
`replacement at a future time. These high—risk
`surgical patients agreed to an attempted PTCA
`with the realization that myocardial revascular—
`ization surgery would be avoided. A few of
`these specific patients
`recently underwent
`PTCA while on percutaneous femorofemora]
`cardiopulmonary bypass.
`Patients were advised that complications aris-
`ing from a coronary occlusion or embolization
`of debris from a vein graft would be managed
`with the use of continuous lytic therapy“ and
`would not be an indication for emergency sur—
`gery. The post—PTCA management has been
`published. 12
`
`Definitions
`
`Multiple—lesion PTCA was defined by the
`dilatation of two or more individual lesions in
`varying combinations of two or more coronary
`vessels, vein grafts,
`internal mammary grafts,
`or in different segments of the same vessel.
`Multiple-lesion PTCA included the dilatation of
`tandem lesions when separated by an angio—
`graphically apparent lesion-free segment.
`A dilatation procedure was considered suc—
`cessful when (1) all
`lesions attempted were
`dilated successfully (a 20 per cent or greater
`reduction in the per cent diameter stenosis with
`less than or equal
`to 50 per cent residual
`narrowing); or (2) the culprit lesion(s) was di-
`
`n W,
`
`,
`
`,,,,,,, "n“ \-« ,__c_v "“O“’O"‘r“‘”“‘“l
`
`successful results were accompanied by a clini-
`cal improvement within 1 week of the proce-
`dure.
`
`Clinical improvement was evaluated by the
`patient’s subjective assessment ofanginal status,
`and/or by noninvasive techniques. An apparent
`symptom-related lesion recurrence was consid-
`ered present when a patient, clinically im-
`proved after PTCA, deteriorated and this wors—
`ening was
`associated with
`angiographic
`evidence of restenosis of one or more lesions.
`
`Follow-up Data
`
`Follow—up data of patients, both successful
`and unsuccessful, were obtained by periodic
`interviews (within 1 week, 3 months, 6 months,
`and yearly), via office visits, telephone calls, or
`written questionnaires that detailed the pa-
`tients Vital status, anginal status, occurrence of
`a myocardial infarction, repeat hospitalizations,
`and/or subsequent PTCA or CABG. A late
`death was defined as an occurrence after hos-
`pital discharge. At a mean time of 3.3 years,
`data were obtained for 98 per cent of patients
`regarding vital status and in 92 per cent con-
`cerning angina] status.
`
`Statistical Analysis
`
`All data have been presented as the mean i
`one standard deviation. The Chi—square test
`with Yates’ correction and univariate analysis
`was utilized. A P value of less than 0.05 was
`considered statistically significant. Life—table
`analysis was performed according to published
`methods.”
`
`PERCUTANEOUS TRANSLUMINAL
`CORONARY ANGIOPLASTY IN PATIENTS
`WITH PRIOR CORONARY ARTERY
`BYPASS SURGERY
`
`Results
`
`Clinical Characteristics (Table 1)
`
`Four-hundred twenty prior CABG patients
`(mean, 83 per cent) underwent PTCA, with 85
`
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`

`PTCA in Patients with Prior Coronary Artery Bypass Surgery
`
`793
`
`Table 1. Clinical Characteristics of420 Prior
`CABG Patients who Underwent PTCA
`420
`
`Patients
`Men
`Women
`Mean age (years)
`Prior infarction
`LVEF $35 per cent
`Anginal Class II—IV (CCSC)
`Chronic lung disease
`Prior stroke
`Chronic renal failure
`
`349 (83%)
`7] (17%)
`58.3 i 8.8
`258 (61%)
`49 (12%)
`355 (85%)
`15 (3.6%)
`15 (3.6%)
`9 (2.1%)
`
`CABG = Coronary artery bypass grafting; CCSC =
`Canadian Cardiovascular Society Class; LVEF : left ven-
`tricular ejection fraction.
`
`per cent having severe angina (Class II to IV).
`Severe left ventricular dysfunction was present
`in 12 per cent of the cases.
`
`Angioplasty Data (Table 2)
`
`Fifty per cent of patients required only one
`lesion, and 30 per cent had two lesions dilated
`to achieve the desired revascularization. A suc—
`
`cessful dilatation was achieved in 88 per cent of
`attempts—87 per cent in native arteries and 91
`per cent in vein grafts. A clinical success (pa-
`tient improvement) was obtained in 86 per cent
`of cases.
`
`Complications (Table 3)
`
`A significant complication (death, emergency
`surgery, or Q wave infarction) occurred in 21
`
`Table 2. Angioplasty Data 0f420 Prior
`CABG Patients
`
`211 (50%)
`127 (30%)
`82 (20%)
`
`784 (mean, 1.9 lesions/patient)
`Lesions
`Lesions attempted per patient
`1 lesion
`2 lesions
`2 3 lesions
`Lesion success related to lesion site
`Native artery
`Vein graft
`Aortic anastomosis
`Shaft (body)
`Distal anastomosis
`Internal mammary artery
`Success
`Lesion success
`Patient success
`Patient success related to
`number of prior CABGS
`249/287 (87%)
`1 prior CABG
`88/108 (81%)
`2 prior CABCs
`3 prior CABGs
`18/18 (100%)
`
`6/7 (88%)
`24 prior CABCs
`CABG = coronary artery bypass grafting.
`
`450/517 (87%)
`219/241 (91%)
`65/76 (86%)
`55/56 (98%)
`99/109 (91%)
`19/26 (73%)
`
`688/784 (88%)
`361/420 (86%)
`
`Table 3. Complications Encountered During PTCA
`in 420 Prior CABG Patients
`PATIENTS
`
`Complications
`Myocardial infarction
`Q Wave MI
`NoneQ Wave MI
`Coronary occlusion
`Mortality
`PTCA related
`Not PTCA related
`Emergency CABG
`Distal embolization
`Number/SVG dilated
`Number/all lesions dilated
`Summary
`Cases with no complications
`Cases with significant
`complications
`
`22 (5.2%)
`10 (2.3%)
`12 (2.9%)
`14 (3.3%)
`11 (2.6%)
`10 (2.3%)
`1 (0.3%)
`6 (1.4 %)
`16 (3.8%)
`16/241 (6.6%)
`16/784 (2.0%)
`
`347 (83%)
`21 (5.0%)
`
`M1 = myocardial infarction; CABG = coronary artery
`bypass grafting; SVC = saphenous vein graft.
`
`patients (5 per cent), with an in-hospital PTCA—
`related mortality of 2.3 per cent. Complications
`encountered were not mutually exclusive, with
`three of the six patients who died having had
`emergency surgery, and in 3 of the 12 deaths,
`an acute Q wave myocardial
`infarction was
`apparent.
`Although patients with only a native artery
`dilatation(s) were more likely to have a signifi-
`cant complication (7.7 versus 2 per cent;
`P<0.05) compared with vein graft dilatation
`patients, no specific complication (myocardial
`infarction, mortality, or emergency surgery) was
`found to be more likely to occur. Patients with
`vein graft dilatations had a low incidence of
`significant complications but an increased inci-
`dence of embolic episodes: Saphenous vein graft
`distal embolizations occurred in 16 patients (3.8
`per cent) and in 6.6 per cent of all vein graft
`lesions attempted. Nevertheless, 83 per cent of
`patients experienced no complication.
`
`Follow-up (Table 4)
`
`During the follow—up period, an assumption
`was made so as not to underestimate the inci—
`dence of lesion recurrence: A lesion “restenosis”
`
`was responsible for (1) any cardiac-related death
`(36 patients);
`(2) all repeat CABGS, with or
`without preoperative angiography (27 patients);
`and (3) clinical deterioration requiring repeat
`PTCA (94 patients). Utilizing this assumption,
`the recurrence rate was 43 per cent (157 of 361
`patients).
`
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`71 (55%)
`31 (24%)
`
`28 (21%)
`
`PATIENTS
`85/94 (90%)
`Repeat successful PTCA (211d)
`Mean lime Isl—End PTCA
`0.8 year
`Patients with angiographic
`Old (lesion recurrence)
`New (lesions not present previ-
`ously)
`Old and new
`Lesion sites
`Native artery
`Anterior descending
`Circumflex
`Right coronary
`Left main coronary
`Vein graft
`Aortic anastomosis
`Shaft (body)
`Distal anastomosis
`Follow-up CABG
`Lute deaths
`Attributed to cardiac disease
`Repeat successful PTCA (3rd)
`Mean time 2nd—3rd PTCA (years)
`Clinical follow-up 2] year after
`PTCA (mean time, 3.3 years)
`(n = 219)
`183/219 (84%)
`Improved angina] status
`117/219 (53%)
`Patients with no angina
`CABC : coronary artery bypass grafting; PTCA =
`percutnneous transluminal coronary angioplasty.
`
`99/104 (95%)
`34/37 (92%)
`36/36 (100%)
`21/23 (91%)
`8/8
`(100%)
`34/40 (85%)
`15/16 (94%)
`11/14 (79%)
`8/10 (80%)
`27 (7.5%)
`39 (11%)
`36
`21/22 (95%)
`l.lyears
`
`A successful second PTCA was performed in
`85 of 94 restenosed patients (90 per cent) at a
`mean time of 9 months after the first PTCA.
`Coronary arteriography showed that 74 per cent
`had had a restenosis of the previously dilated
`lesion, with or without disease progression, and
`26 per cent had had only a new lesi0n(s) (disease
`progression). Without
`those 20 patients with
`disease progression,
`the presumptive recur—
`rence rate would be 38 per cent (137 of 361
`patients).
`There were 219 patients alive 12 or more
`months after their PTCA procedure (mean time,
`3.3 years). Clinical data indicated that 84 per
`cent of patients had an improved angina] status,
`and 53 per cent had no angina.
`A second clinical recurrence occurred in 22
`of 85 patients (26 per cent), with a third PTCA
`(mean time, 12 months) performed successfully
`in 21 patients (95 per cent).
`
`Life-table Analysis
`
`The cumulative probability ofsurvival for the
`entire group, at 87 months, was 86 i 3 per
`
`u, 55“ch (mam, u.
`
`_-_ 3pc. cent yuaaua Lemme,
`
`95 i- 3 per cent; P<0.01; Fig. 2) and ventricular
`ejection fraction (less than or equal to 35 per
`cent, 77 i 8 per cent versus greater than 35
`per cent, 91 i 2 per cent; P<0.001; Fig. 3).
`Age did not afiect survival initially (greater than
`or equal to 70 years, 89 i 2 per cent versus
`less than 70 years, 92 i 5 per cent; P=NS;
`Fig. 4).
`When death or post—PTCA repeat CABG was
`used as the cardiac event marker, the probabil»
`ity was 77 i 5 per cent that a patient would
`be alive and would not have undergone repeat
`CABG (see Fig. 1) at 87 months. In addition,
`the cardiac event—free (death, CABG, and/0r
`myocardial infarction) probability was 72 i 5
`per cent at 87 months (see Fig. 1).
`
`DISCUSSION
`
`Percutaneous transluminal coronary angio-
`plasty and CABG are effective rcvascularization
`techniques for symptomatic patients with ob—
`structive coronary artery disease. Neither tech-
`nique cures atherosclerosis. The disease process
`continues as long as the patient remains alive
`and,
`in time, will affect
`the arteries or vein
`grafts,
`the latter often virulentlyfl “1
`'3' 2r“ "3 A
`second operation (CABG) has been estimated
`to be performed in 1.1 per cent of prior CABG
`patients per year for the first 5 years, and in
`3.9 per cent per year thereafter. Although a
`cumulative percentage of reoperation has been
`reported to be 19 per cent at 12 years?“ other
`studieszz have shown that reintervention has
`been necessary because of symptom reeurrence
`in 12 per cent of patients after
`their first
`CABcga repeat CABG in 8.3 per cent, a
`PTCA in 2.3 per cent, and both in 1.2 per cent.
`Repeat surgical revascularization usually was
`done because of vein graft closure; when occur—
`ring early in the postoperative course,
`it was
`considered secondary to surgical
`technique,
`and, when late, because of atherosclerotic dis-
`ease within the graft conduit or in the vessel
`distal to the anastomotic site.
`
`Page 6
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`

`PTCA in Patients with Prior Coronary Artery Bypass Surgery
`
`795
`
`1.00
`
`.90
`
`.80
`
`.70
`
`.60
`
`Death + CABG + MI
`
`Death
`
`Death + CABG
`
`1
`
`6
`
`
`12
`18
`24
`30
`36
`42
`48
`54
`60
`66
`72
`78
`84
`
`
`
`CUMULATIVEPROBABILITYOFSURVIVAL
`
`Figure l. bile-table analysis of patients with prior CABG after successlnl PTCA for cardiac-related events; lower numbers
`represent IIIL' putiunth at risk for (lentil, death and repunl myocardial n-msculurization (CABG), and both plus myocardial
`infill‘ctiun {MIL
`
`MONTHS
`
`Repeat Coronary Artery Bypass Grafting
`(Table 5)
`
`Patients who underwent repeat CABG were
`younger and had better ventricular function
`
`(:0;
`than the original bypass surgery patient
`Imrt. "1"” In surgical series I)I.tl.)IISI](.'(I since 19:5”.
`the mean time from the first
`to the second
`CABG has ranged between 36 and 98 months,
`with mortality”- 17 2“ and morbidity (Table 6)
`
`Male ~ Female
`
`1.00
`
`.90
`
`.80
`
`'70
`
`‘60
`
`.50
`
`
`
`CUMULATIVEPROBABILITY0FSURVIVAL
`
`
`
`a
`
`Female
`
`I Male
`
`p 5 0.01
`
`11
`11
`19
`20
`26
`28
`36
`41
`46
`48
`55
`42
`46
`70
`77
`114
`125
`159
`170
`225
`276 233
`
`
`1
`6
`12
`18
`24
`30
`36
`42
`48
`54
`60
`MONTHS
`Figure 2. Life-table .nmlgsis for patients with prior CABG after successful PTCA showing a statistically significant
`Increased probability of snn'iml for women.
`
`Page 7
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`

`_s O O
`
`in 0
`
`2:0 0
`
`g 0
`
`in o
`
`in o
`
`
`
`CUMULATIVEPROBABILITYOFSURVIVAL
`
` W
`
`o
`
`-
`
`> 35% LVEF
`
`s 35% LVEF
`
`p 5 0.001
`
`275
`56
`
`247
`34
`
`241
`30
`
`192
`19
`
`179
`16
`
`142
`11
`
`132
`8
`
`91
`8
`
`85
`4
`
`1
`
`6
`
`12
`
`18
`
`24
`MONTHS
`Figure 3. Life-table analysis for patients with prior CABG after successful PTCA showing a statistically significant
`probability of survival for patients with left ventricular ejection fraction (LVEF) greater than 35 per cent.
`
`30
`
`36
`
`42
`
`48
`
`increased significantly as compared with that at
`the initial procedure. Variables affecting sur—
`vival adversely after repeat CABG included
`advanced age, left ventricular dysfunction, and
`
`diffuse coronary disease.l' 1017'“ A recurrence
`of angina after a repeat CABG has occurred at
`a yearly rate of 3.5 to 7.2 per cent.” ”1 Repeat
`CABG has been very effective in selected pa—
`
`1.00
`
`.90
`
`.80
`
`7°
`
`£0
`
`.50
`
`
`
`CUMULATIVEPROBABILITYOFSURVIVAL
`
`
`
`298
`33
`
`256
`25
`
`247
`24
`
`196
`15
`
`180
`15
`
`142
`11
`
`130
`10
`
`91
`6
`
`84
`5
`
`0
`
`I
`
`< 70 Years
`
`i 70 Years
`p : NS
`
`1
`
`6
`
`12
`
`18
`
`24
`MONTHS
`Figure 4. Life-table analysis of patients with prior CABG after successful PTCA showing no change in survival when
`stratified by age (less than 70 versus more than 70 years old).
`
`30
`
`36
`
`42
`
`48
`
`Page 8
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`

`PTCA in Patients with Prior Coronary Artery Bypass Surgery
`
`797
`
`PATIENTS
`
`PER CENT’
`
`Table 5. Published Results Regarding Mortality and Survival of Patients who have
`Undergone Repeat Bypass Surgery
`I)I‘EIIATIVE M()IITALI'IY
`
`(PER CENT) .— PER CEIxT
`TIME
`1st
`2nd
`cps
`
`39
`3.1
`5.3
`—
`3
`283
`Foster (CASS)
`36
`7
`4
`7
`4.6
`112
`Lamas”
`6.2
`106
`Schaflm
`—
`—
`2.8
`94 (5 years)
`7
`58
`Hall17
`7
`2.8
`9.2
`75 (5 years)
`8. 6
`64
`Cameron5
`98
`—
`7
`82 (10 years)
`8.6
`89
`Keon20
`54
`1.2
`5.6
`87 (9 years)
`7
`625
`Loop:5
`91
`—
`3.2
`82 (5 years)
`—
`—
`8
`10
`636
`Dorrosu
`—
`—
`5.8
`8
`514
`Normal LV function
`
`77 17.1
`
`LV dysfunction
`111
`2
`
`*Per cent of original cohort of lst coronary artery bypass graft (CABC); Time = time from lst to 2nd CABC in months;
`CPS = cumulative probability of survival; CASS = Coronary Artery Surgical Study; lst and 2nd refer to the lst and 2nd
`coronary bypass surgery; (—) = not reported; LV = left ventricle.
`
`tient groups. Angioplasty can be equally effica—
`cious in appropriately selected patients, how-
`ever, and can obtain clinical success while being
`less invasive and having a lower morbidity and
`mortality. The relief of angina and long-term
`survival was comparable with PTCA and CABG.
`
`avoided as being unfeasible technically because
`of (1) the difficulty of opening the chest rapidly;
`(2) finding the appropriate vessels; and (3) re-
`establishing blood flow to the compromised
`vessels in a reasonable time frame,
`thereby
`preventing a myocardial infarction.
`
`Angioplasty in Prior Bypass Patients (Table 7)
`
`Angioplasty in Vein Grafts (see Table 6)
`
`The 88 per cent angiographic success rate,
`reported herein, resulted in a clinical improve—
`ment in 86 per cent of the patients. The major
`complications encountered in our series were
`not
`increased significantly as compared with
`those studies with predominantly single—vessel
`coronary disease patients who did not have the
`high proportion of multivessel coronary artery
`disease (89 per cent), patients with left ventric—
`ular dysfunction (12 per cent), and geriatric
`patients (15 per cent). The incidence of emer-
`gency CABG was low (1.4 per cent) and,
`in
`part, was planned. Emergency surgery was
`
`The complications associated with PTCA in
`prior CABG patients were of concern, espe
`cially with regard to their management. The
`complications encountered, although not neg-
`ligible, however, were comparable to those
`occurring with the repeat surgical alternatives.
`Angioplasty of vein graft lesions had a better
`success rate and lower incidence of complica~
`fions than PTCA attempted on native artery
`lesions. The vein graft restenosis rate, however,
`was significantly higher than that
`in native
`arteries. In this series, the restenosis rate varied
`between 24 per cent (the distal anastomosis)
`
`PATIENTS
`
`Table 6. Complications Reported with Repeat Coronary Bypass Surgery
`STERNAL
`WOUND
`RESPIRATORY
`MORTALITY
`PERIOP MI
`CVA
`COMPLICATIONS
`INFECTION
`(PER CENT)
`(PER CENT)
`(PER CENT)
`[PER CENT)
`(PER CENT)
`
`8.0
`2.6
`5.4
`14
`3.2
`625
`L001)”
`14
`H
`—
`3
`2.8
`112
`Allen1
`7.5
`0.9
`0.9
`19
`2.8
`106
`schafl:E
`6
`5.3
`283
`Foster (CASS)
`o
`3
`1
`‘——————
`*Operativc mortality.
`Periop = perioperal'i\'e; MI = myocardial infarction; CVA = cerebrovasclar accident; (—) = not reported; CASS =
`Coronary Artery Surgical Study.
`
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`

`NU/LLDD
`LLlNlliAL
`\Al).\1rlrlkikllUNhl
`(PER CENT)
`PATIENTS
`VG/NA
`(PER CENT)
`DEATH/CABG/MI (PER CENT)
`
`71/—
`Coteq
`82
`83/—
`85/70
`0
`1.2
`3.6
`Ernst”
`83
`33/59
`91/86
`0
`0
`2. 4
`46/—
`19/—
`84/84
`5
`0
`5
`—/78
`Reedel‘m
`19
`
`166/
`/
`Douglas13
`166
`IQZ
`52/47
`90/88
`1
`4
`2
`— /63
`Corbelli“
`94
`Plntkmv’]
`101
`107/—
`92/7
`— /53
`2
`7
`6
`Dorms”
`76
`53/81
`85/86
`3
`1
`1
`46/60
`Dorms
`53/84
`2.3
`1.4
`2.3
`88/86
`241/517
`420
`(present study)
`VG = vein graft; NA = native artery; VC/NA = lesions attempted in vein graft and native artery; angio = angiographic;
`clinical refers to clinical improvement; CABC = coronary artery bypass grafting, MI = myocardial infarction; angina, less
`is in comparison with status prior to lst PTCA; (—) = not reported.
`
`and 50 per cent (the aortic anastomosis). Sur—
`prisingly, patients in whom a vein graft dilata—'
`tion was done were more likely to have an
`uneventful and successful procedure than when
`a native artery lesion was related. The reason
`for this difference cannot be determined from
`the data, but could be related to the fact that
`when only a native artery was dilated to achieve
`revascularization,
`then (1)
`the myocardial re-
`serve had been severely compromised because
`of vein graft closure; (2) the vessel dilated had
`been bypassed previously and was more prone
`to dissection; (3) if a vessel closed, emergency
`surgery was not to be peiformed; and (4) PTCA
`was being attempted in patients with more
`diffuse disease. Although the incidence of distal
`embolization after vein graft dilatation was of
`considerable concern,
`the sequelae of such
`events appeared not
`to have the predicted
`disastrous consequences.21 5 Distal emboliza-
`tion was managed successfully utilizing re—
`peated balloon inflations, which fractionated the
`debris, and often was done in combination with
`continuous lytic therapy (urokinase, 2000 U per
`minute for 24 to 48 hours).
`
`Follow—up
`
`Follow—up data of successful PTCA in prior
`CABC patients showed that (1) repeat PTCA
`was performed successfully (90 per cent) in 26
`per cent of patients; and (2) the lesion recur-
`rence rate approached 43 per cent, if all patients
`who died of cardiac causes and those who
`underwent repeat CABC and/0r PTCA were
`included, In fact, the coronaiy arteriograms in
`
`the repeat PTCA patients (9 months after the
`first PTCA) showed that 25 per cent of patients
`had new lesions without any recurrence of
`previously dilated lesions. Clinical deterioration
`did not always represent failure of the PTCA
`but, rather, might have indicated progression
`of disease.
`The clinical results during follow up appeared
`satisfactory, with anginal relief being 84 per
`cent and abolition of angina having been
`achieved in 53 per cent of the patients. These
`results were comparable to those in patients
`after repeat CABC, with only 47 per cent
`having significant anginal relief 5.5 years after
`surgery.25
`The data reported herein have shown that
`PTCA in prior CABC patients: (1) accomplished
`an angiographically successful dilatation with
`equal facility in vein grafts (91 per cent) and
`native arteries (84 per cent); (2) the site of vein
`graft dilatation (proximal or distal anastomosis,
`or body shaft) did not change the success rate;
`and (3)
`the dilatation of the culprit
`lesion(s)
`achieved an immediate clinical improvement in
`86 per cent of patients.
`
`PERCUTANEOUS TRANSLUMINAL
`CORONARY ANGIOPLASTY IN PATIENTS
`5 YEARS OR MORE AFTER CORONARY
`BYPASS SURGERY
`
`The age of a saphenous vein graft, in and of
`itself, has been considered a relative contrain—
`dication to the use of PTCA. This assessment
`was based on the pathologic evaluation (gross
`and histologic) of surgically removed vein grafts
`
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`

`PTCA in Patients with Prior Coronmy Artery Bypass Surgery
`
`799
`
`Table 9. Angioplasty Data in Patients 5 Years or
`More Remote from Their Last Coronary Bypass
`
`Surgery
`ALL PATIENTS
`
`Lesions attempted
`457
`Mean number/patient
`1.8
`Lesions attempted/patient
`l Lesion
`2 Lesions
`2 3 Lesions
`Success according to
`site dilated
`Native artery
`Saphenous vein graft
`Aortic anastomosis
`Shaft (body)
`Distal unustomosis
`Internal mammary artery
`Successes
`406/457 (89%)
`Success/lesions
`
`Success/patients 216/258 (84%)
`Success/lesions refers to angiographic success; success/
`patients refers to clinical improvement.
`
`260/304 (86%)
`129/144 (90%)
`42/50 (84%)
`39/40 (98%)
`48/54 (89%)
`(78%)
`
`7/9
`
`133 (52%)
`81 (31%)
`44 (17%)
`
`Complications (Table 10)
`
`No complication occurred in 81 per cent of
`cases. A significant complication (death, emer—
`gency surgery, or Q wave myocardial infarction)
`occurred in 15 patients (5.8 per cent). The in—
`hospital mortality related to PTCA was 2.3 per
`cent. Five of the six patients whose death was
`
`and on the surgical experience that excessive
`manipulation of old vein grafts could produce
`distal embolization.“" “' m, m 21
`
`section details our experience with
`This
`PTCA in patients who are 5 years or more
`remote from their last CABG who had dilation
`
`of a native arterial lesion(s) and/or a vein graft
`lcsion(s). A comparison often will be made
`between those patients who had only a native
`arterial lesion(s) dilated and those who had a
`vein graft
`lesion(s) dilated with or without a
`concomitant dilatation of a native artery le-
`sion(s).
`
`Results
`
`Clinical Characteristics (Table 8)
`
`The clinical characteristics of 258 patients
`who underwent PTCA 5 years or more after
`CABG showed that the predominant presenting
`symptom in 86 per cent of patients was severe
`angina (Class II to IV). A comparison ofpatients
`in whom PTCA was performed on saphenous
`vein graft and those in whom only native artery
`PTCA was performed showed no statistical dif-
`ference in their clinical characteristics.
`
`Angioplasty Data (Table 9)
`
`The results of the angioplasty procedure
`showed no statistical difference in angiographic
`success, whether a native artery or saphenous
`vein graft
`lesion was dilated. Success was
`achieved in 89 per cent of lesions attempted
`(90 per cent of vein graft and 86 per cent of
`native artery lesions) and produced a clinical
`improvement in 84 per cent of patients.
`
`Table 8. Clinical Characteristics of Patients who
`had PTCA 5 Years or More After Coronary Bypass
`Graft Surgery
`ALL PATIENTS
`
`258
`
`Patient data
`Men
`Women
`Mean age (years)
`Prior myocardial infarction
`Left ventricular ejection
`fraction 535 per cent
`Anginal Class II—IV (CCSC)
`222 (86%)
`13 (5.0%)
`Lytic therapy utilization
`
`221 (86%)
`37 (14%)
`58.7 t 9
`161 (62%)
`32 (12%)
`
`CCSC = Canadian Cardiovascular Society 'Class;
`therapy = urokinase or streptokinase.
`
`lytic
`
`Table 10. Complications of PTCA in Patients 5
`Years or More Remote from Their Last Coronary
`Bypass Surgery
` PATIENTS
`Complications
`Myocardial infarction
`Q Wave M1
`Non-Q Wave MI
`Coronary spasm
`Coronary occlusion
`Mortality
`Related to PTCA
`Not related to PTCA
`Emergency CABG
`Embolization
`Number/only SVC dilated
`Number/all lesions dilated
`Cases with:
`No complications
`210 (81%)
`
`Significant complications 15 (5.8%):
`
`20 (7.8%)
`
`4 (1 6%)
`7 (2.7%)
`7 (2.7%)
`
`3 (1.2%)
`13 (5.0%)
`
`9 (3.5%)
`11 (4.3%)
`
`6 (2.3%)
`l (0.4%)
`
`13/144 (9.0%)*
`13/457 (2.8%))“
`
`MI : myocardial infarction; Q wave M1 = transmural
`infarction; non-Q wave MI = subendocardial MI; PTCA 2
`percutaneous transluminal coronary angioplasty; CABG =
`coronary artery bypass grafting; SVC = saphenous vein
`graft.
`*Number of embolic episodes pcr saphenous vein lesions
`dilated.
`TNnrnber of embolic episodes per all lesions dilated.
`iEmergency CABC, myocardial infarction, and death.
`
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`

`sel within 30 minutes following PTCA and the
`fifth had an abrupt closure 6 hours post-proce—
`dure. The sixth patient died after balloon infla»
`tion of electromechanical dissociation.
`Although the saphenous vein graft patients
`were more likely to have a significant compli-
`cation than the native artely—only patients (8.5
`versus 2.6 per cent; P<0.05), no specific c0111-
`plication statistically was more likely to occur.
`Saphenous vein graft patients had fewer signif-
`icant complications but had an increased inci-
`dence of vein graft embolic episodes over native
`artery—only patients (9.5 versus 1.4 per cent;
`P<0.05). These embolic episodes were associ-
`ated with a significant increase in noneQ wave
`infarctions (6 versus 2.8 per cent; P<0.05).
`
`Follow-up (Table 11)
`
`the same as-
`During the follow—up period,
`sumption as described in the first section was
`made so as not to underestimate the incidence
`of lesion recurrence: A lesion “restenosis” was
`considered responsible for any cardiac-related
`death (21 patients), all repeat CABGs (23 pa-
`tients), and/0r repeat PTCA (58 patients). The
`
`1
`
`A
`
`underwent PTCA for new disease only were
`excluded, then the presumptive recurrence rate
`would be 43 per cent. A successful second
`PTCA was performed in 52 of 58 patients (90
`per cent). Coronary arteriography in the pa-
`tients undergoing repeat PTCA showed that 47
`per cent had a restenosis of the lesion dilated,
`27 per cent had both a restenosis ofa previously
`dilated lesion and a new lesion, and 26 per cent
`had a new lesion without
`lesion recurrence.
`Thus, 15 0f 58 patients (26 per cent) underwent
`the second PTCA procedure because of new
`disease and had no lesion recurrence; excluding
`these 15 patients would yield a presumptive
`recurrence rate of 40 per cent. Native artery-
`only patients statistically were more likely to
`undergo repeat CABC than saphenous vein
`graft patients (16 versus 5 per cent, P<0.05).
`The lesion sites data (see Table 11) have not
`indicated the recurrence rate of a particular
`site; on