Restenosis after successful percutaneous transluminal coronary angioplasty: serial angiographic follow-up of 229 patients

To further understand the temporal mode and mechanisms of coronary restenosis, 229 patients were studied by prospective angiographic follow-up on day 1 and at 1, 3 and 6 months and 1 year after successful percutaneous transluminal coronary angioplasty. Quantitative measurement of coronary stenosis was achieved by cinevideodensitometric analysis. Actuarial restenosis rate was 12.7% at 1 month, 43.0% at 3 months, 49.4% at 6 months and 52.5% at 1 year. In 219 patients followed up for greater than or equal to 3 months, mean stenosis diameter was 1.91 +/- 0.53 mm immediately after coronary angioplasty, 1.72 +/- 0.52 mm on day 1, 1.86 +/- 0.58 mm at 1 month and 1.43 +/- 0.67 mm at 3 months. In 149 patients followed up for greater than or equal to 6 months, mean stenosis diameter was 1.66 +/- 0.58 mm at 3 months and 1.66 +/- 0.62 mm at 6 months. In 73 patients followed up for 1 year, mean stenosis diameter was 1.65 +/- 0.56 mm at 6 months and 1.66 +/- 0.57 mm at 1 year. Thus, stenosis diameter decreased markedly between 1 month and 3 months after coronary angioplasty and reached a plateau thereafter. In conclusion, restenosis is most prevalent between 1 and 3 months and rarely occurs beyond 3 months after coronary angioplasty.     

Primary angiographic success rates of percutaneous transluminal coronary angioplasty

Three distinct periods in catheter design have been identified since the advent of percutaneous transluminal coronary angioplasty (PTCA) in 1977. In the first period PTCA was performed using a double-lumen balloon catheter that had a fixed, flexible guidewire at the tip. In the second period, an independent, steerable guidewire and the steerable catheter system were used. In the third period, low-profile catheters were introduced. A total of 2,969 patients who had single-vessel PTCA of a native coronary artery was separated into groups according to the period during which PTCA was performed. Introduction of the steerable catheter system was accompanied by improvement in primary success rate in PTCA attempts on the right coronary artery (78% vs 88%, p less than 0.005). Introduction of the low-profile catheter was accompanied by improved primary success in PTCA attempts on the left anterior descending coronary artery (LAD) (90% vs 94%, p less than 0.005). The percentage of PTCA attempts on the LAD decreased over the 3 periods (70% to 60% to 56%), while the percentage of attempts on the left circumflex artery increased (7% to 12% to 16%). Before steerable and low-profile catheters were used, there were significant differences in ability to reach and cross stenoses among the 3 major coronary arteries. These differences no longer exist. These results indicate that technical improvements and operator experience have made stenoses in all 3 major coronary arteries equally accessible to dilatation catheters and that primary success rates and reasons for failure in these arteries are now similar.     

Follow-up clinical results in patients undergoing percutaneous transluminal coronary angioplasty

Complete follow-up data were obtained from 229 consecutive patients who underwent percutaneous transluminal coronary angioplasty (PTCA) between 1979 and 1982 (mean follow-up 14 months, range 6 to 37). Single-vessel disease was present in 143 and multivessel disease in 86. PTCA was successful in 153 patients (67%). Failure was followed initially by bypass surgery in 59 and by continued medical therapy in 17. After successful PTCA, 90% of patients were improved subjectively and 74% were asymptomatic at follow-up. After unsuccessful PTCA but prompt bypass, 90% were improved subjectively and 85% were asymptomatic. Among the 229 patients, 39 (17%) required an additional intervention because of angina during follow-up; 15 of these had repeat PTCA and 18 had bypass surgery. Among patients with successful PTCA, revascularization was complete in 77% and partial in 23%. The completeness of revascularization with PTCA had a significant impact on follow-up. The follow-up data of patients with successful single-vessel PTCA and of those with multivessel disease with complete revascularization were similar. When the patients with complete revascularization were compared with those with multivessel disease but incomplete revascularization, the follow-up data were characterized by a higher incidence of angina or need for bypass surgery in the latter group (63%) than in the former group (29%); those with incomplete revascularization also had a significantly reduced event-free survival.     

Three year anatomic, functional and clinical follow-up after successful percutaneous transluminal coronary angioplasty

Because the long-term anatomic effects of percutaneous transluminal coronary angioplasty are unknown, follow-up evaluations including coronary angiography, treadmill exercise testing and rest and bicycle exercise radionuclide angiography were performed in 46 patients 6.3 +/- 2.0 and 37.6 +/- 3.6 (mean +/- SD) months after they had undergone successful single lesion angioplasty. The severity of the coronary stenosis decreased significantly at each evaluation; the mean diameter stenosis was 66 +/- 13% before angioplasty, 30 +/- 13% immediately after and 26 +/- 16% and 19 +/- 13% at 6 months and 3 years, respectively. Exercise time increased from 9.8 +/- 4.4 minutes before angioplasty to 18.3 +/- 4.5 minutes immediately after the procedure and remained at that level at 6 months (20.3 +/- 4.6 minutes) and 3 years (18.2 +/- 4.5 minutes). Left ventricular ejection fraction during exercise decreased 4 +/- 6% compared with rest before angioplasty, but increased 7 +/- 7% immediately after angioplasty and this increase was maintained at 6 months (+/- 6 +/- 7%) and 3 years (+/- 4 +/- 6%). Before angioplasty, 1 patient was in Canadian Heart Association functional class 0, 15 were in class II, 24 in class III and 6 in class IV. Three years later, 25 were in class 0, 10 in class I, 7 in class II and 4 in class III. These results indicate that the short-term anatomic and functional success of coronary angioplasty is maintained for at least 3 years.     

Angiographic follow-up after multivessel percutaneous transluminal coronary angioplasty

In 100 consecutive patients undergoing multivessel percutaneous transluminal coronary angioplasty (PTCA), dilation was attempted in 207 arteries. Primary success was achieved in 85 patients. Complications occurred in 8 patients: acute myocardial infarction in 5 and need for emergency coronary artery bypass surgery in 5. Control angiography was done in 77 of 85 patients (91%) with primary success at a mean of 12 +/- 6 months. Complete revascularization had been achieved in 59 patients and incomplete revascularization in 18. Angiographic restenosis was found in 39 of 77 patients (51%) and in 47 of 143 arteries (33%) at 9 +/- 7 months. The restenosis rate was 57% for chronic total occlusions (8 of 14) and 30% for stenoses (39 of 129). The restenosis rate was significantly higher for the left anterior descending coronary artery (40%) than for the left circumflex coronary artery (21%). However, the significance was lost after exclusion of chronic total occlusions. A higher residual stenosis and a high coronary wedge pressure were predictors for restenosis. Restenosis was clinically silent in 14 patients (18%). Repeat PTCA was done in 19 patients with recurrence and elective surgery in 8. Clinical follow-up was available in all patients at 24 +/- 12 months. Patients with incomplete revascularization had less favorable clinical follow-up results than patients with complete revascularization: 44% (8 of 18) vs 81% (48 of 59) were asymptomatic (p less than 0.005), and 28% (5 of 18) vs 5% (3 of 59) had undergone elective bypass surgery during follow-up (p less than 0.005). Most patients with restenosis after multivessel PTCA had only 1-vessel restenosis and only 7% had restenosis of all lesions.     

Clinical and sequential angiographic follow-up six months and 10 years after successful percutaneous transluminal coronary angioplasty

Sequential angiographic follow-up is needed for interpreting coronary events that occur after successful percutaneous translumial coronary angioplasty (PTCA). One hundred eight consecutive patients who had undergone successful dilatation were followed for 10 years, and quantitative sequential angiograms were recorded at 6 months (n = 101) and 10 years (n = 68). The 10-year event rate was: 5.8 +/- 2.4% for cardiac death, 9.7 +/- 3.3% for Q-wave acute myocardial infarction, 18.3 +/- 4.5% for additional surgery, and 22.4 +/- 4.9% for repeated angioplasty. Using Cox's proportional-hazards regression, multivessel coronary artery disease (CAD) (RR 5.6; 95% confidence intervals [CI] 1.2 to 24.7; p = 0.02), restenosis within 6 months (RR 7.8; 95% CI 3.1 to 20.0; p = 0.0001), and CAD progression over 10 years (RR 10.6; 95% CI 1.3 to 87.1; p = 0.004) were the strongest predictors of all-cause death, repeated PTCA, and additional surgery, respectively, after controlling for age and coronary risk factors. The minimal luminal diameter of 48 narrowings with complete sequential angiographic follow-up and without restenosis remained stable from 6 months (2.13 +/- 0.60 mm) to 10 years (2.18 +/- 0.61 mm). Disease progression was similar in nondilated arteries and dilated arteries (32% vs 30%). The 10-year risk of coronary events was higher in patients with baseline multivessel CAD than in those with 1-vessel CAD because of more frequent progression of CAD (RR 3.8; 95% CI 1.6 to 6.8; p = 0.001). Thus, early cardiac events after successful PTCA were related to restenosis, and late events to CAD progression. Nevertheless, after the restenosis period, the target lesion remained stable for the next 10 years. Coronary disease progression was not related to the angioplasty procedure.     

Atrial pacing during percutaneous transluminal coronary angioplasty: results and comparison with exercise treadmill testing

Right atrial pacing (RAP) was used to immediately assess improvement in threshold for myocardial ischemia in 23 patients undergoing angiographically successful percutaneous transluminal coronary angioplasty (PTCA). Multiple coronary lesions were present in 19 patients, and 15 had incomplete revascularization. All patients had RAP done immediately before and after completion of all dilatations, and in 13 patients pre- and post-PTCA exercise treadmill tests (ETT) were also performed. Angina occurred in 16 (70%) patients during pre-PTCA RAP, but in only 4 (17%) after PTCA (p less than .05). The electrocardiogram was positive for ischemia (horizontal or downsloping ST depression greater than or equal to 1 mm) in 18 patients (78%) during pre-PTCA RAP. However, 13 patients (57%) continued to have an ischemic response during post-PTCA RAP (not significant-NS). In 4 patients with multiple coronary lesions who had sequential pacing studies after PTCA of each lesion, the maximum degree of ST depression decreased by 1 mm or more after each dilatation in 3 patients but remained greater than or equal to 1 mm in all. In the 13 patients undergoing both RAP and ETT, angina developed in 7 during pre-PTCA RAP and in 2 after PTCA (p less than .05), compared with 8 and 3 (p less than .05) during pre- and post-PTCA ETT, respectively. Ischemic ST depression occurred in 9 patients during pre-PTCA RAP and in 6 after PTCA (NS), and in 8 and 6 (NS) during pre- and post-PTCA ETT, respectively. Concordance between the two tests was good.(ABSTRACT TRUNCATED AT 250 WORDS)     

Morphologic correlates of coronary angiographic patterns at the site of percutaneous transluminal coronary angioplasty

Over the last 10 years considerable interest has been paid in the angiographic recognition of successful percutaneous transluminal coronary artery angioplasty (PTCA), complication of the technique, and angiographic predictors of restenosis. This report summarizes various angiographic patterns visualized at the site of angioplasty and correlates these patterns with morphologic findings. Of 66 patients undergoing PTCA for chronic or unstable angina pectoris, 76 PTCA sites were available for analysis. The two most common angiographic patterns at the angioplasty site (intimal flap = 43%, intraluminal haziness = 38%) correlated morphologically with intimal-medial splits with localized dissections (79%). Shallow, superficial intimal lesions, laminated thrombus, and adventitial tears accounted for the remaining morphologic changes. Eight PTCA sites without morphologic injury corresponded to smooth wall changes and spasm at angiography.     

Arterial changes after percutaneous transluminal coronary angioplasty: results at autopsy

Light and electron microscopic examinations were performed on 20 coronary artery sites from nine patients who had undergone percutaneous transluminal coronary angioplasty. Twelve successfully dilated sites without prior thrombosis showed evidence of a tear in the luminal surface (with or without fracture of an atheroma) even at 140 days after angioplasty. The tear split through a relatively undistensible intima in 9 (75%) of the 12 sites. Two successfully dilated sites with prior thrombosis showed an intraintimal tear with a widely lacerated fibrous cap and thin mural thrombus. After dilation, the occluded prior nonthrombosed site showed marked protrusion of a separated plaque. An occluded prior thrombosed site after dilation revealed intraintimal canal-like hematoma. Four sites that occluded after balloon passage revealed a dissecting hematoma in three and plaque disruption in the other.     

运动试验评估经皮冠状动脉腔内成形术的疗效

31例经皮冠状动脉腔内成形术(PTCA)成功的病例,于 PTCA 前后作运动负荷试验,冠状动脉术前平均狭窄82.6±16.0%,术后狭窄17.7±6.2%。90%病例 PTCA 术后运动试验较术前明显进步。PTCA 后运动试验阳性伴心绞痛者,应警惕发生血管再狭窄。运动负荷试验可作为评估 PTCA 效果的常规检查。     

Early results after percutaneous transluminal coronary angioplasty in 400 patients

In a consecutive series of 400 patients treated by percutaneous transluminal coronary angioplasty 212 had single vessel disease, 142 had multivessel disease with only one vessel dilated, and 46 had multivessel dilatation. In addition sequential stenoses were dilated in the same vessel in all groups. There was no mortality among patients with single vessel disease. Success rates varied from 83% to 90% according to the artery in which angioplasty was attempted. Urgent surgery was required by 3.8%. Primary success was lower (74%) in the presence of multivessel disease and complications were more frequent, with four deaths (2.8%). In 46 patients with multivessel disease in whom all important lesions were dilated during the same procedure the overall primary success rate was 76% and within the last year of the study it was 91%. One (2%) patient died and three (7%) required urgent surgery. Twelve (86%) out of 14 stenosed vein grafts were successfully dilated and eight (53%) chronically occluded vessels were re-opened; in both groups there were no deaths, no infarctions, and no need for urgent surgery. In all groups symptoms improved greatly and predischarge exercise tests showed that there was no reversible ischaemia in 94% of patients with single vessel disease or in 65% of patients with incomplete revascularisation. Six months after the procedure 95% of the patients had improved symptomatically and 80% had normal exercise tests after one year. Percutaneous transluminal coronary angioplasty is the method of choice in single vessel disease and its use also results in a high proportion of other patients becoming symptom free. Complication rates are low and for selected patients results that are equivalent to those of cardiac surgery are obtained.     

Long-term exercise performance after percutaneous transluminal coronary angioplasty and coronary artery bypass grafting

In our first 169 consecutive patients admitted to undergo percutaneous transluminal coronary angioplasty (PTCA) serial bicycle ergometric exercise sessions were scheduled to assess long-term-exercise performance. In 160 of these 169 patients (95%) an average of seven ergometric measurements were available during a mean follow-up period of 29 months (range 1 to 60 months). Two groups were formed. One consisted of 132 patients in whom PTCA was successful and the other consisted of 28 patients with failure of PTCA who subsequently underwent coronary artery bypass grafting (CABG) either on an emergency basis (12 patients) or as an elective procedure (16 patients). Exercise performance was expressed as work capacity in watts according to the highest completed exercise stage. In the successful PTCA group the actual work capacities increased from 74 +/- 42 W (mean +/- SD) before PTCA to 122 +/- 47 W at the most recent follow-up examination. In patients who underwent emergency or elective CABG the respective figures were 73 +/- 34 or 65 +/- 37 W before surgery and 120 +/- 41 or 119 +/- 41 W at the most recent follow-up examination (p less than .005 for all preprocedure to postprocedure comparisons). Successful PTCA and CABG after failed PTCA improve work capacity significantly. Comparison of our results with those of surgical studies indicates that a failed attempt at PTCA before CABG does not compromise the functional outcome of the operation, regardless whether it is done on an emergency or on an elective basis.     

Coronary angioplasty: clinical and angiographic follow-up

To evaluate the clinical status and restenosis rate after percutaneous transluminal coronary angiography (PTCA), 251 consecutive patients who had undergone a successful procedure from February 1979 to May 1983 were studied. Angiography was done routinely in 92 of the initial 100 consecutive patients in whom the procedure was successful (group I), 1 to 11 months (mean 6) after PTCA. Restenosis occurred in 37 of 92 patients (40%); all but 2 (who had collateral flow to the restenosed vessel) had symptoms. Conversely, 44 of 46 asymptomatic patients had no restenosis. The other 159 patients (group II) were followed up clinically, with angiography performed only if signs or symptoms of ischemia recurred. Restenosis suspected clinically and confirmed angiographically occurred in 35 of 92 patients (38%) in group I and 36 of 154 patients (23%) in group II. Of 251 patients with follow-up of at least 6 months, 109 patients (43%) became symptomatic. Of 109 symptomatic patients, 104 consented to coronary angiography; restenosis was found in 67%, progression of narrowing in other arteries occurred in 13%, and the remaining patients were presumed to have large or small vessel vasospasm. The mortality rate for the entire group was 0.8%. When repeat angioplasty was applied to patients with restenosis, over 80% of the group improved at an average follow-up time of 21 months. Symptomatic restenosis may occur less often when higher balloon inflation pressures are used during PTCA.     

Balloon angioplasty results in increased segmental coronary distensibiliy: A likely mechanism of percutaneous transluminal coronary angioplasty

Objectives. The purpose of this study was to evaluate the hypothesis that the increase in lumen area induced by percutaneous transluminal coronary angioplasty is secondary to a change in lesion (segmental) distensibility.Background. Despite the widespread use of coronary angioplasty, the precise mechanism (or mechanisms) of lumen area improvement remains poorly understood.Methods. Quantitative coronary angiography was used to measure the minimal (contrast agent filled) balloon diameters at 1 to 5 atm, inclusive, during the first and final balloon inflations in 24 lesions successfully treated with coronary angioplasty. To rule out possible confounding effects due to changes in balloon material distensibility during repeated inflations, five control balloons were studied ex vivo. In parallel, intravascular ultrasound imaging was utilized to compare the segmental distensibility (change in lumen area during the cardiac cycle) of eight disease-free and seven mildly diseased coronary segments and seven segments after successful balloon angioplasty.Results. Minimal balloon diameters increased significantly between the first and final inflations (46%, 33%, 26%, 14% and 10% at 1, 2, 3, 4 and 5 atm, respectively, all p < 0.0001), demonstrating an increase in arterial distensibility after successful coronary angioplasty. No significant changes in balloon diameters were observed during sequential initial inflations at 1 and 2 atm (n = 5). Minimal increases in Balloon diameters were observed during repeated balloon inflations in the ex vivo studies (4.9 ± 1% [mean ± SEM]). A distensibility index, derived from the intravascular ultrasound data, was not different between the balloon-dilated and the normal segments but was significantly lower in mildly diseased sites (14.7 ± 2.2 vs. 12.9 ± 1.2 vs. 6.9 ± 1.9, respectively, p < 0.05) despite a smaller plaque area (7.3 ± 1 vs. 11.3 ± 1 mm², proximal/nondilated vs. dilated segments, respectively, p < 0.05).Conclusions. Coronary distensibility is significantly impaired in atherosclerotically diseased coronary segments and increases significantly after balloon angioplasty. This increase in segmental coronary compliance after coronary angioplasty may create a larger lumen area by allowing the vessel to distend in response to normal intraarterial pressure.