Long-term follow-up after percutaneous transluminal coronary angioplasty in patients with single-vessel disease

Long-term clinical outcome after stent implantation in coronary arteries

The long-term clinical outcome after planned and unplanned stent implantation was assessed in a single-center, observational study in 178 patients who underwent coronary stent implantation between November 1986 and July 1994. Main outcome measures were survival and event-free survival at 5 years (Kaplan-Meier method). Independent predictors for event-free survival were determined by using multivariate logistic regression analysis. Patients underwent planned (group 1, n 3 101) or unplanned (group 2, n 3 77) stent implantation. During the in-hospital period, there were no deaths. The incidence of Q-wave and non-Q-wave acute myocardial infarction (AMI), coronary artery bypass graft (CABG) and repeat percutaneous transluminal coronary angioplasty (PTCA) was 5.0%, 2.0% and 4.0%, respectively, in group 1, versus 32.5%, 23.4% and 10.4%, respectively, in group 2. During the follow-up period (median 4.0 years, range 0.29-9.8 years), the incidence of death, AMI, and repeat revascularization (CABG and PTCA) was 5.9%, 8.9% and 40.6%, respectively, in group 1, versus 1.3%, 5.2% and 36.4%, respectively, in group 2. Survival and event-free survival at 5 years was 73 (7%) and 47 (7%), respectively, for patients who underwent planned stent implantation. It was 98 (0.1%) and 34 (6%), respectively, for patients who underwent unplanned stent implantation. At the end of follow-up, 31.9% of patients had angina pectoris class III or IV (Canadian Cardiovascular Society). The long-term clinical outcome after both planned and unplanned stent implantation was characterized by a high incidence of repeat revascularization. It is conceivable that changes in stent design and implantation techniques, in addition to novel therapeutic approaches addressing neointima formation and progression of atherosclerosis, may improve the long-term clinical outcome.

Outcome following percutaneous transluminal coronary angioplasty performed before 1990

The goal of this follow-up study was to assess the long-term survival of all patients having undergone a first PTCA between 1981 and 1990 and to relate the outcome to the baseline clinical and angiographic state. Although PTCA has become a widely accepted therapeutic choice for revascularization, the authors lacked information on long-term outcome. Data was collected by questionnaire, the end points being a second PTCA, MI, CABG, death or any of these events. The survival curves were constructed using the Kaplan-Meier method. Multivariate analysis was performed by a Cox proportional hazards model. Complete follow-up data were collected for 1,071 patients for a mean period of 7.4 years (SEM +/- 1.98 months) with a range of 0 to 14 years. Mean age was 57 years. PTCA was successful in 85% of patients. In-hospital event rates were death 1.3%, MI 4.4%, and emergency CABG 2.9%. Overall survival at 14 years was 69% (SEM +/- 9.6%) and event-free survival was 47% (SEM +/- 5.8%). MI rate was 11%, CABG 15%, and 20% of patients underwent repeat PTCA. Presence of cardiovascular risk factors, poor left ventricular ejection fraction, and prior CABG were significantly associated with poorer event-free survival. The short-term observations are consistent with results reported by the other follow-up studies. In addition, the study found a total survival rate 14 years after a first PTCA of 69% and 47% of the cohort remained event free.

Tissue-selective expression of dominant-negative proteins for the regulation of vascular smooth muscle cell proliferation

The transcription factors c-myb and c-myc are essential for vascular smooth muscle cell (VSMC) replication and are rapidly induced following mitogenic stimulation of quiescent VSMCs in vitro and in vivo following balloon catheter injury. Consequently, interference with c-myb and c-myc function provides a possible avenue for the prevention of VSMC proliferation associated with intimal hyperplasia. We have carried out studies focused on the inhibition of VSMC proliferation using dominant-negative gene constructs incorporating the DNA-binding domains of the c-myb or c-myc genes fused to the repressor domain of the Drosophila engrailed gene. Transient transfection of rat, rabbit and human vascular SMCs results in a dramatic inhibition of proliferation for at least 72 h after transfection. Furthermore, this inhibition of cellular proliferation was found to be due, at least in part, to the induction of apoptosis. Coupling expression of the chimeric dominant-negative proteins to transcriptional regulatory elements of the human vascular smooth muscle alpha-actin gene allows specific targeting of vascular smooth muscle cells.

Outcome of target sites escaping high-grade (>70%) restenosis after percutaneous transluminal coronary angioplasty

This study examined the fate of target sites that escaped high-grade restenosis (> or = 70% diameter narrowing) after percutaneous transluminal coronary angioplasty. Although favorable long-term prognosis after successful percutaneous transluminal coronary angioplasty is well documented, little is known about the stability of target sites. Long-term follow-up (mean 6.5 years, range 1.0 to 12.0) was performed in 693 patients with 948 narrowings (stenosis <70% in diameter at follow-up coronary angiography). Among them, 249 patients (36%) with 303 target sites received late follow-up coronary angiography. The relation of target sites to the culprit lesions for coronary events or newly developed angina was angiographically reviewed and progression/regression was also examined, focusing on the target sites. Regression was observed in 16 of 255 target sites in subjects with <50% stenosis and in 21 of 48 sites in the group with midgrade stenosis of 50% to 69% luminal narrowing (16 of 255, 6.3% vs 21 of 48, 43.8%, p <0.001). Progression was observed in 33 and 4 sites (33 of 255, 12.9% vs 4 of 48, 8.3%; p = NS) in each group, respectively. The rest remained within the same range of stenosis. Culprit lesions for 2 acute myocardial infarctions, 7 unstable anginas, and 17 newly developed anginas were related to the original target sites. Three lesions developed in the midgrade stenosis group. Those 26 lesions were a component of 8.6% of 303 angiographically confirmed sites and 2.7% of total target sites. Target sites that escape high-grade restenosis frequently regress and become stable plaques and rarely trigger coronary events.

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.

Long-term angiographic prognosis of lesions dilated by coronary angioplasty

BACKGROUND

To examine the long-term outcome of coronary angioplasty, lesions that remained patent after 3 to 12 months were monitored angiographically at 3-year intervals. There were 252 lesions successfully dilated (from 83% +/- 13% preprocedural stenosis to 19% +/- 14% residual stenosis) between 1983 and 1986 that remained patent on follow-up angiography (23% +/- 15% stenosis) and were monitored further at our outpatient department.

METHODS AND RESULTS

Repeat angiography was done for 186 lesions at 2 to 4 years and showed that 179 were patent (0% to 50% stenosis), one had mild stenosis (55% to 70% stenosis), and six had severe stenosis (75% to 100% stenosis). Angiography was repeated for 138 lesions at 5 to 7 years, showing that 127 were patent, four had mild stenosis, and seven had severe stenosis. Finally, angiography was performed for 78 lesions at 8 to 10 years, showing that 63 were patent, four had mild stenosis, and 11 had severe stenosis.

CONCLUSIONS

Although numerous lesions were lost to follow-up, most appeared to remain patent for 4 years, after which a significant number developed restenosis.

Coronary bypass grafting for single-vessel coronary artery disease: a 17-year review with short- and long-term follow-up

STUDY OBJECTIVES

We reviewed our short- (30 days) and long-term (up to 17 years) experience with surgical revascularization for patients with angiographically documented isolated single-vessel coronary artery disease.

DESIGN

Retrospective study of single-vessel coronary artery bypass procedures performed from January 1980 through June 1996. During this time, 100 consecutive patients underwent a single-vessel coronary artery bypass. All patients were men with a mean age of 59+/-9 years (range, 35 to 78 years) and a mean ejection fraction of 56+/-8% (range, 35 to 77%). The vessels bypassed included the left anterior descending in 66 (66%), right coronary artery in 31 (31%), and the obtuse marginal in 3 (3%).

RESULTS

Short-term results reveal no deaths and six (6.0%) complications. Long-term follow-up by chart review and telephone survey was available in 87 (87%) patients at a mean of 46.9 months (range, 12 to 151 months). Cumulative freedom from angina and repeated revascularization was 93% and 98% at 1 year and 55% and 81% at 10 years, respectively (Kaplan-Meier).

CONCLUSION

Single-vessel coronary artery bypass for isolated single-vessel disease can be performed with minimal morbidity and no mortality and provides excellent long-term relief of angina.

Correlation of residual stenosis immediately after coronary angioplasty with long-term prognosis

This study evaluated the correlation of residual stenosis after percutaneous transluminal coronary angioplasty with the long-term prognosis. Among consecutive 1,230 patients who underwent coronary angioplasty in the National Cardiovascular Center in Osaka, Japan, 894 patients had de novo lesions. Of these, the 70 patients with acute myocardial infarctions and 105 with unstable angina who had emergency coronary angioplasties were excluded from the study. Among the remaining 719 patients, successful dilatation of the main target vessel was achieved in 592 patients, who then comprised the study group. They were divided into three groups according to their residual stenosis (RS) immediately after coronary angioplasty: group A, RS < 15% (n=208); group B, 15% < or = RS < or = 35% (n=286), and group C, 35% < RS < 50% (n=98). The duration of follow-up was 1,668, 1,660, and 1,680 days in group A, B, and C, respectively. The groups A, B, and C were not significantly different in terms of age, history of myocardial infarction, left ventricular ejection fraction, number of diseased vessels and target vessels, and risk factors such as hypertension, hyperlipidemia, and diabetes mellitus. Primary end point of follow-up was defined as death from any cause and the second end point was occurrence of cardiac events. Kaplan-Meier survival analysis showed significant differences among the three groups. Moreover, survival curves seem to be dependent on the degree of post-procedural residual stenosis. Multivariate analysis using a Cox proportional hazard regression model showed that age, ejection fraction, and residual stenosis were independent determinants of event-free, cardiac, and total survival. Residual stenosis immediately after coronary angioplasty is an independent contributor to long-term clinical prognosis in patients treated with successful balloon coronary angioplasty.

Effectiveness and cost effectiveness of single bolus treatment with abciximab (Reo Pro) in preventing restenosis following percutaneous transluminal coronary angioplasty in high risk patients

OBJECTIVE

To assess the clinical effectiveness and cost effectiveness of abciximab in preventing restenosis after percutaneous transluminal coronary angioplasty (PTCA).

DESIGN

Data from a previous study, the EPIC trial, were used because only this trial was able to provide event data capable of constructing a cost effectiveness analysis over six months. All other study data reviewed supported the findings of the EPIC trial. To provide indicative results on long term health outcomes, survival and event-free survival were extrapolated using US epidemiological data in a Markov modelling process.

SETTING AND PATIENTS

Patients who were at high risk for ischaemic complications after PTCA, treated in the standard manner.

INTERVENTIONS

Abciximab was added to the regimen of intravenous heparin and aspirin.

RESULTS

The EPIC study (n = 2099) indicated an 8.1% absolute reduction in serious cardiovascular events (95% confidence interval 3.1% to 12.7%) and a 23% relative risk reduction (p = 0.001). Based on the six month trial period, the additional cost per patient free from a serious event (Australian dollars) is $13,012 and for a special risk/benefit measure of outcome, the additional cost is $14,243. Epidemiological data support extended survival and ischaemic event-free survival with clinically successful PTCA. The results of the modelled analysis indicate a cost per additional life-year gained of $5547 and a cost per additional year event-free of $4285.

CONCLUSIONS

At up to six months abciximab offers improvements in clinically important outcomes. A modelling exercise explores and highlights the likelihood of significant long term health benefits. The analysis provides information for decision makers and funders to consider the value for money of abciximab.

Long-term (4- to 6-year) outcome of Palmaz-Schatz stenting: paucity of late clinical stent-related problems

OBJECTIVES

The purpose of this prospective single-center study was to evaluate the longer-term outcome of Palmaz-Schatz stenting in the treatment of native coronary and saphenous vein bypass graft disease.

BACKGROUND

The STRESS (Stent Restenosis Study) and BENESTENT (Belgian Netherlands Stent) trials have demonstrated a decrease in both angiographic restenosis and the need for repeat revascularization in the 1st year for vessels treated by stenting rather than balloon angioplasty. Longer-term (1 to 5 years) clinical results of Palmaz-Schatz stenting are not yet well established. Late migration of the stent, metal fatigue, endarteritis and late restenosis have all been proposed as potential late clinical complications of coronary stent implantation.

METHODS

The study cohort consisted of 175 consecutive patients who underwent elective placement of 194 Palmaz-Schatz stents in 185 vessels. Clinical events (death, myocardial infarction, recurrent angina or any revascularization) were assessed at 6 weeks, 2, 4 and 6 months, 1 year and yearly thereafter. Clinical follow-up was available on all patients at a mean +/- SD of 54 +/- 17 months.

RESULTS

Angiographic success was achieved in 173 patients (98.9%); angiographic restenosis was observed at 6 months in 26.1% of target sites. The survival rate was 86.7% at 5 years, with a 5-year event-free survival rate decreasing progressively to 50.7%, reflecting primarily repeat revascularization procedures (41.2% at 5 years). However, the rate of repeat revascularization of the treatment site (target site revascularization [TSR]) was 14.4%, 17.7% and 19.8% at 1, 3 and 5 years, respectively, with late (> 1 year) TSR driven by in-stent restenosis in only 3 patients (1.7%). Rates of both 5-year survival (70.5% vs. 93.4%) and event-free survival (21.1% vs. 63.3%) were lower for patients who underwent saphenous vein graft (SVG) stenting than for those with native coronary artery stenting. However, 5-year TSR rates were similar for SVGs (21.9%) and native vessels (19.2%), indicating that the higher incidence of repeat revascularization for SVGs was due to an increase in non-TSR, driven by progressive disease at other sites.

CONCLUSIONS

The long-term outcome of stenting shows stability of the treated lesion, with only a slight increase in TSR between 2 and 5 years (17.1% to 19.8%). The progressive increase in repeat revascularization over that period (24% to 41%) and most ongoing late events can be attributed to the progression of coronary disease at other sites, rather than to late deterioration of the stent result itself. Such non-TSR events account for the majority of clinical events in the patients who underwent SVG stenting.

Women fare no worse than men 10 years after attempted coronary angioplasty

A retrospective review of cardiac events occurring in all patients who underwent attempted coronary angioplasty in the first 5 years of our experience (1980-1985) was undertaken. Follow-up data were obtained from the civil registry, hospital records, patient, family, and referring physician. Patient survival curves were constructed and the outcome of women and men was compared. Eight hundred fifty-six patients, 172 women and 684 men with a mean age of 60.0 and 55.3 years, respectively, underwent attempted coronary angioplasty with an overall procedural success rate of 82%, 77.7% in women and 83.1% in men. Follow-up data were obtained in 837 patients (97.8%) with a mean period of 9.6 years (range 0-13.3 years). The estimated 10 year survival in women was identical to men [79%, 95% confidence interval (CI) 72.6-85.4% vs. 78%, 95% CI 74.6-81.4%] as was the 10 year event-free survival (men 36%, 95% CI 32.0-40.0% vs. women 37%, 95% CI 29.2-44.8%), with a similar proportion of major cardiac events-death, myocardial infarction, coronary artery bypass surgery, and repeat angioplasty. When women were matched to men for age and previous myocardial infarction, factors found to be associated with an adverse outcome, there was no significant difference. Additionally, outcome was compared after patients were matched for maximum nominal balloon size as an estimate of vessel size, with no significant difference between women and men. At follow-up, women complained of significantly more anginal symptoms than men (59.2% vs. 44.0%, P < 0.05) and took significantly more antianginal medication.

Clinical outcome 10 years after attempted percutaneous transluminal coronary angioplasty in 856 patients

OBJECTIVES

This study reports the 10-year outcome of 856 consecutive patients who underwent attempted coronary angioplasty at the Thoraxcenter during the years 1980 to 1985.

BACKGROUND

Coronary balloon angioplasty was first performed in 1977, and this procedure was introduced into clinical practice at the Thoraxcenter in 1980. Although advances have been made, extending our knowledge of the long-term outcome in terms of survival and major cardiac events remains of interest and a valuable guide in the treatment of patients with coronary artery disease.

METHODS

Details of survival, cardiac events, symptoms and medication were retrospectively obtained from the Dutch civil registry, medical records or by letter or telephone or from the patient's physician and entered into a dedicated data base. Patient survival curves were constructed, and factors influencing survival and cardiac events were identified.

RESULTS

The procedural clinical success rate was 82%. Follow-up information was obtained in 837 patients (97.8%). Six hundred forty-one patients (77%) were alive, of whom 334 (53%) were symptom free, and 254 (40%) were taking no antianginal medication. The overall 5- and 10-year survival rates were 90% (95% confidence interval [CI] 87.6% to 92.4%) and 78% (95% CI 75.0% to 81.0%), respectively, and the respective freedom from significant cardiac events (death, myocardial infarction, coronary artery bypass surgery and repeat angioplasty) was 57% (95% CI 53.4% to 60.6%) and 36% (95% CI 32.4% to 39.6%). Factors that were found to adversely influence 10-year survival were age > or = 60 years (> or = 60 years [67%], 50 to 59 years [82%], < 50 years [88%]), multivessel disease (multivessel disease [69%], single-vessel disease [82%]), impaired left ventricular function (ejection fraction < 50% [57%], > or = 50% [80%]) and a history of previous myocardial infarction (previous myocardial infarction [72%], no previous infarction [83%]). These factors were also found to be independent predictors of death during the follow-up period by a multivariate stepwise logistic regression analysis. Other factors tested, with no influence on survival, were gender, procedural success and stability of angina at the time of intervention.

CONCLUSIONS

The long-term prognosis of patients after coronary angioplasty is good, particularly in those <60 years old with single-vessel disease and normal left ventricular function. The majority of patients are likely to experience a further cardiac event in the 10 years after their first angioplasty procedure.

Cost-effectiveness of coronary angioplasty versus medical treatment: the impact of cost-shifting

BACKGROUND

Coronary angioplasty (PTCA) offers improved symptom control over medical treatment in patients with stable angina and single-vessel disease. However, it is uncertain if PTCA is more cost-effective. Cost-shifting could also influence the provision of PTCA.

METHODS

Data from the only randomised trial comparing PTCA to medical therapy (ACME study) were used with costs from an Australian teaching hospital to estimate the costs and freedom from angina in 100 patients over three years. The incremental cost-effectiveness of PTCA, and the potential for cost-shifting were also examined.

RESULTS

Although the total cost of treating 100 patients over three years with PTCA ($678,978) was higher than a medical strategy ($631,078), PTCA was more cost-effective ($10,930 versus $12,682 per patient free of angina). The incremental cost-effectiveness of PTCA ($3875 per extra patient free of angina) was also substantially less than the cost of the medical strategy. These should be considered crude estimates as they were based on limited data on resource use. The hospital could reduce costs by pursuing a medical strategy, but 54% of the savings would result from shifting the cost of treating patients to the Federal Government and patients. By performing PTCA on privately insured rather than Medicare patients, the hospital could shift $29,876 per 100 patients to the Federal government and private insurance funds.

CONCLUSIONS

From society's perspective, PTCA may be more cost-effective than a medical strategy. However, the financial interests of the hospital are best served by limiting PTCA or restricting PTCA to privately insured patients. Cost-shifting may have a major impact on the provision of PTCA. The costs of providing medical services need to be weighed against the cost of not providing them.

Outcome five years after percutaneous transluminal coronary angioplasty or coronary artery bypass grafting for significant narrowing limited to the left anterior descending coronary artery

Percutaneous transluminal coronary angioplasty (PTCA) and coronary artery bypass grafting (CABG) are both used widely for angina but information about their comparative efficacy is limited. This study compared the outcome of 358 consecutive patients undergoing initial revascularization for significant narrowing of the left anterior descending artery (LAD) by PTCA (n = 254) or CABG (n = 104) from 1987 to 1989. PTCA was successful in 93% but complicated by urgent CABG in 3%. A left internal mammary graft was used in 88% of those having elective CABG. There was 1 perioperative death. Follow-up data were obtained after a median interval of 5.5 years (maximum 7.1). Rates for freedom from death (97% PTCA vs 93% CABG, p = 0.06) were similar, but CABG patients had greater rates for freedom from chest pain recurrence (74% CABG vs 48% PTCA, p < 0.0001), myocardial infarction (98% vs 92%, p = 0.04), and from need for further revascularization (99% vs 67%, p < 0.0001). Both groups achieved similar status, with 81% of PTCA and 90% of CABG patients having angina no worse than functional class I. Quality-of-life index was high for both groups (0.983 +/- 0.034/1.000 vs 0.987 +/- 0.032/1.000, p = 0.3). Both PTCA and CABG result in excellent survival, functional ability, and quality of life, but patients undergoing PTCA require more procedures to achieve this.