Predictive factors of restenosis after multivessel percutaneous transluminal coronary angioplasty

[Colchicine-Phoenix from the ashes]

Colchicine is an anti-inflammatory herbal medicine with a history stretching back thousands of years. It is a cornerstone in the acute and prophylactic treatment of gout and has secured a permanent place in the standard pharmacological repertoire for familial Mediterranean fever, pericarditis, neutrophilic dermatoses, Behçet's disease and severe aphthous ulcers refractory to oral treatment. The US Food and Drug Administration (FDA) has recently approved colchicine to reduce the risk of myocardial infarction, stroke, coronary revascularization and cardiovascular death in adult patients with established atherosclerotic disease or with multiple risk factors for cardiovascular diseases. The recommendation level for cardiovascular prophylaxis was raised from IIb to IIa in the current European Society of Cardiology (ESC) guidelines from 2024. Clinical studies in recent years also demonstrated an effect for acute coronary syndrome and atrial fibrillation. This review article highlights the efficacy and safety profile of colchicine and provides insights into recent and potential future evidence-based fields of application.

Intrastent Restenosis: A Comprehensive Review

The primary objective of this paper is to delineate and elucidate the contemporary advancements, developments, and prevailing trajectories concerning intrastent restenosis (ISR). We aim to provide a thorough overview of the most recent developments in this area, covering various aspects such as pathophysiological insights, therapeutic approaches, and new strategies for tackling the complex challenges of ISR in modern clinical settings. The authors have undertaken a study to address a relatively new medical challenge, recognizing its significant impact on the morbidity and mortality of individuals with cardiovascular diseases. This effort is driven by the need to fully understand, analyze, and possibly improve the outcomes of this emerging medical issue within the cardiovascular disease field. We acknowledge its considerable clinical implications and the necessity for innovative methods to mitigate its effects on patient outcomes. Therefore, our emphasis was directed towards elucidating the principal facets of the condition's prevalence, expounding upon the foundational mechanisms underscoring conspicuous restenosis, and delineating the risk factors relevant in shaping the contemporary landscape of diagnostic and therapeutic modalities. This thorough examination aims to provide a comprehensive understanding of the various dimensions of the condition, including epidemiological data, pathophysiological complexities, and clinical considerations critical for evaluating and enhancing current diagnostic and treatment approaches.

Contemporary Management of Stent Failure: Part One

The occurrence of in-stent restenosis (ISR) still remains a daunting challenge in the current era, despite advancements in coronary intervention technology. The authors explore the underlying pathophysiology and mechanisms behind ISR, and describe how the use of different diagnostic tools helps to best elucidate these. They propose a simplistic algorithm to manage ISR, including a focus on how treatment strategies should be selected and a description of the contemporary technologies available. This article aims to provide a comprehensive outline of ISR that can be translated into evidence-based routine clinical practice, with the aim of providing the best outcomes for patients.

Understanding and managing in-stent restenosis: a review of clinical data, from pathogenesis to treatment

The lumen diameter reduction after percutaneous coronary intervention (PCI) is well known as "restenosis". This phenomenon is due to vessel remodeling/recoil in case of no-stent strategy or, in case of stent employ, "neointimal proliferation" that consists in an excessive tissue proliferation in the luminal surface of the stent otherwise by a further new-occurring atherosclerotic process called "neoatherosclerosis". The exact incidence of in-stent restenosis (ISR) is not easy to determine caused by different clinical, angiographic and operative factors. In the pre-stent era the occurrence of restenosis ranged between 32-55% of all angioplasties, and drop to successively 17-41% in the bare metal stents (BMS) era. The advent of drug-eluting stent (DES), especially 2nd generation, and drug-coated balloon (DCB) further reduce restenosis rate until <10%. We here review the main characteristics of this common complication of coronary interventions, from its pathogenesis to the most appropriate treatment strategy.

Influence of insulin resistance on in-stent restenosis in patients undergoing coronary drug-eluting stent implantation after long-term angiographic follow-up

OBJECTIVE

Previous studies have reported that insulin resistance is related to early in-stent restenosis (ISR) after coronary stenting. This study aimed to evaluate the influence of insulin resistance on the long-term angiographic outcome in patients undergoing coronary drug-eluting stent (DES) implantation.

MATERIALS AND METHODS

Within a single hospital-based cohort of patients (n=529) who underwent coronary DES implantation, angiographic follow-up was performed successfully for 417 study patients at 12-48 months after coronary stenting. ISR was defined as stenosis of at least 50% of the luminal diameter. Fasting plasma glucose and fasting plasma insulin were measured. Insulin resistance was expressed by the homeostasis model assessment index (HOMA-IRI).

RESULTS

Among the 417 patients who completed angiographic follow-up (mean 17.5±10.2 months), 58 patients (13.9%) had ISR whereas the remaining 359 patients (86.1%) did not have ISR. Patients with ISR had higher insulin resistance index (IRI) than nonrestenosis patients (P=0.004). Multiple logistic regression analysis (logit) showed that IRI was associated significantly with ISR (adjusted odds ratio 1.476, 95% confidence interval 1.227-1.776; P<0.001). In the nondiabetes subgroup of 309 patients, IRI was higher in patients with ISR than in nonrestenosis patients, as confirmed in a separate logit analysis (adjusted odds ratio 1.456, 95% confidence interval 1.152-1.839; P=0.002). Multiple linear regression analysis showed that IRI was associated significantly with in-stent diameter stenosis degree (P=0.043).

CONCLUSION

Insulin resistance was associated with ISR in patients undergoing coronary DES implantation at long-term angiographic follow-up.

The safety and feasibility of transradial cutting balloon angioplasty: immediate results, benefits, and limitations

Cutting balloon angioplasty can reduce the restenosis rate more than conventional balloon angioplasty, but is traditionally performed through a femoral artery. However, it is not clear how useful a transradial approach would be for cutting balloon angioplasty. This study was conducted to examine the safety, feasibility, and limitations of transradial as opposed to transfemoral cutting balloon angioplasty. From November 1999 to August 2001, 177 patients underwent cutting balloon coronary angioplasty. We compared the success rate, angiographic results, and complication rates of two groups of patients, those undergoing transradial (168 lesions from 153 patients) and those undergoing transfemoral (24 lesions from 24 patients) cutting balloon angioplasty. In both groups of patients who had similar clinical and target lesion characteristics. the percentage of lesions that required balloon predilation (27.4% vs 29.2%). stenting (7.7% vs 4.2%), and adjunct balloon dilation (28.0% vs 33.3%) due to dissection (35.7% vs 33.3%) or suboptimal results were comparable. Both approaches achieved a 100% primary success rate with similar acute gain (2.02 +/- 0.68 mm vs 1.94 +/- 0.70 mm), residual (luminal) diameter stenosis (19.2 +/- 11.7% vs 17.0 +/- 12.7%). proportion of lesions that achieved TIMI 3 flow (98.8% vs 100%), and clinical success rate (98.8% vs 95.8%). However, patients undergoing transradial cutting balloon angioplasty had earlier ambulation and a significantly shorter hospital stay than those undergoing a transfemoral approach (2.80 +/- 2.67 days vs 4.75 +/- 5.44 days, P = 0.005). We conclude that the transradial approach is a feasible and safe alternative to the transfemoral approach for cutting balloon angioplasty. In addition, it offers patients early ambulation and a short hospital stay.

Combination of minimally invasive coronary bypass and percutaneous transluminal coronary angioplasty in the treatment of double-vessel coronary disease: Two-year follow-up of a new hybrid procedure compared with "on-pump" double bypass grafting

OBJECTIVE

Percutaneous transluminal coronary angioplasty (PTCA) or surgery can be chosen as first-line therapies in multiple-vessel coronary disease. A mammary-to-left anterior descending (LAD) graft is the most important statistical determinant of a favorable outcome after coronary artery bypass grafting (CABG) and can be performed with lower morbidity off pump through a minithoracotomy. PTCA and stenting of the "non-LAD" vessels compete with CABG in terms of patency rates. Our purpose was to compare a combination of minimally invasive direct coronary artery bypass (MIDCAB) and PTCA with double CABG as a treatment for double-vessel coronary artery disease involving the proximal LAD.

METHODS

Two matched groups of 20 patients with double-vessel coronary disease undergoing either sequential MIDCAB and PTCA (group 1) or double CABG on cardiopulmonary bypass (group 2) were compared. Angiographic control, complications, hospital costs, quality of life, and 2-year follow-up of ischemia are reported.

RESULTS

All bypasses were patent at early control. Three adverse events were noted in group 1 and 17 in group 2. The hybrid-procedure group exhibited a shorter intensive care unit stay, fewer blood products transfused, less pain, better early quality of life, faster return to work, and similar cost. Three patients required a second PTCA in group 1, one of which for restenosis. At 2 years all the patients are asymptomatic with no residual ischemia.

CONCLUSIONS

We conclude from this pilot study that the hybrid procedure is feasible and appears to be a safe therapy for double-vessel coronary artery disease and that it appears to generate less perioperative morbidity than classic double CABG does. Therefore we believe that there is room to undertake prospective randomized studies on a larger-scale basis.

Long-term outcome of angioplasty for multivessel coronary disease: importance and price of complete revascularization

BACKGROUND

Complete revascularization of multivessel coronary artery disease (MVD) by coronary artery bypass surgery has been shown to improve outcome, but there is a lack of similar data for patients treated by angioplasty.

METHODS

Therefore, a consecutive series of 250 patients with MVD was separated into two groups, those with complete revascularization (n=101) and those with incomplete revascularization (n=149). Six-month 'clinical restenosis' rate assessed by stress myocardial perfusion scintigraphy or symptom-driven angiography and long-term 32 months outcome were compared with an equally sized group of single vessel disease (SVD) patients.

RESULTS

MVD patients with complete revascularization had a higher 'clinical restenosis' rate than patients with SVD (35 vs. 22%, P<0.02), although restenosis rate per treated vessel was similar (23%, 18%, P NS). If this higher early restenosis rate were accepted as 'price' for complete MVD angioplasty, long-term event-free survival was no longer different from that of SVD patients (86 vs. 93%, P NS). In contrast, patients with incomplete multivessel angioplasty had a significantly worse long-term outcome (22% events), especially if initially untreated, non-occluded vessels remained untreated (25% events).

CONCLUSION

MVD angioplasty with complete revascularization has a long-term event-free survival similar to that of SVD angioplasty but at the price of a higher rate of 6-month restenosis and repeat interventions.

A randomised trial of endoluminal reconstruction comparing the NIR stent and the Wallstent in angioplasty of long segment coronary disease: results of the RENEWAL Study

BACKGROUND

The role of coronary stents in reducing the incidence of acute complications and late restenosis after angioplasty has been established in randomized studies focusing on simple, short coronary lesions. The development of long coronary stents has provided a safe and predictable means of treating long coronary lesions, but this carries with it a higher risk of restenosis. By comparing the outcome of treating long lesions with two different stent types, we aimed to assess the influence of stent design rather than the nature of long lesions per se on the relatively high restenosis rates in this subgroup.

METHODS

This study was designed to assess procedural complications and 6-month restenosis rates in a randomized trial comparing a slotted tube stent with a self-expanding stent for the treatment of long coronary lesions. Randomization of vessels to either stent occurred after successful balloon angioplasty. Intravascular ultrasound (IVUS) was used to assess and optimize stent deployment. The patients were restudied angiographically and by IVUS at 6 months.

RESULTS

A total of 82 patients (85 vessels) were recruited (slotted tube stent, n = 44 vessels; self-expanding stent, n = 41 vessels). Successful deployment occurred in 41 (100%) of 41 of the self-expanding stent group and 41 (93%) of 44 of the slotted tube stent group. There was no difference in lesion length between the two groups (slotted tube stent, 26.6 +/- 6.9 [SD] mm; self-expanding stent, 28.7 +/- 9.8 [SD] mm; P = .2), but the mean length of the self-expanding stent was greater than that of the slotted tube stent (41.6 +/- 18.8 [SD] mm vs 35.4 +/- 16.2 [SD] mm, respectively; P < .05). There was no significant difference in the rate of major events between the two groups at 6-month follow-up. The angiographic restenosis rate at follow-up was less in the slotted tube stent group, but this did not reach statistical significance (26% vs 46%, respectively; P = .1) and the target lesion revascularization rate was similar for both groups (7.9% vs 7.7%, respectively; P = .8). IVUS assessment of plaque/stent ratios suggested a greater plaque burden in the self-expanding stent compared with the slotted tube stent at follow-up (0.42 +/- 1.2 [SD] vs 0.3 +/- 0.08 [SD]), but this was not statistically significant (P = .1).

CONCLUSIONS

Long stents can be safely and successfully deployed in long segment coronary disease, with an acceptable 6-month target lesion revascularization rate. Our results showed a trend toward lower angiographic restenosis and a lesser in-stent plaque burden at follow-up in the slotted tube stent compared with the self-expanding stent. This suggests that stent design may influence the restenotic process in long coronary lesions.

Clinical outcome following coronary angioplasty in dialysis patients: a case-control study in the era of coronary stenting

BACKGROUND

Balloon coronary angioplasty has been reported to be ineffective in patients treated for end stage renal disease because of a high restenosis rate.

OBJECTIVE

To compare the clinical outcome following coronary angioplasty with provisional stenting in dialysis versus non-dialysis patients.

DESIGN

A case-control study.

PATIENTS

Of 1428 consecutive patients who underwent coronary angioplasty, 100 (7%) were being treated for end stage renal disease. These were compared with 100 control patients matched for age, sex, coronary lesions, presence of diabetes mellitus, and rate of coronary stenting (40%).

MAIN OUTCOME MEASURES

In-hospital and one year clinical outcome.

RESULTS

The rates of procedural success (90% v 93%), in-hospital mortality (1% v 0%), stent thrombosis (0% v 0%), and Q wave myocardial infarction (0% v 1%) were similar in dialysis and non-dialysis patients. One year clinical outcome after coronary angioplasty was similar in the two groups in terms of clinical restenosis (31% v 28%) and myocardial infarction (6% v 2%), but cardiac death was more common in dialysed patients (11% v 2%, p < 0.03).

CONCLUSIONS

Dialysis does not increase the risk of clinical restenosis after coronary angioplasty with provisional stenting. Coronary angioplasty is a safe and effective therapeutic procedure in selected dialysis patients with culprit lesions accessible to stenting. However, the one year survival is reduced in this high risk population.

Clinical outcome following coronary angioplasty in dialysis patients: a case–control study in the era of coronary stenting

BACKGROUND

Balloon coronary angioplasty has been reported to be ineffective in patients treated for end stage renal disease because of a high restenosis rate.

OBJECTIVE

To compare the clinical outcome following coronary angioplasty with provisional stenting in dialysis versus non-dialysis patients.

DESIGN

A case–control study.

PATIENTS

Of 1428 consecutive patients who underwent coronary angioplasty, 100 (7%) were being treated for end stage renal disease. These were compared with 100 control patients matched for age, sex, coronary lesions, presence of diabetes mellitus, and rate of coronary stenting (40%).

MAIN OUTCOME MEASURES

In-hospital and one year clinical outcome.

RESULTS

The rates of procedural success (90% v 93%), in-hospital mortality (1% v 0%), stent thrombosis (0%v 0%), and Q wave myocardial infarction (0% v 1%) were similar in dialysis and non-dialysis patients. One year clinical outcome after coronary angioplasty was similar in the two groups in terms of clinical restenosis (31% v 28%) and myocardial infarction (6% v 2%), but cardiac death was more common in dialysed patients (11% v2%, p < 0.03).

CONCLUSIONS

Dialysis does not increase the risk of clinical restenosis after coronary angioplasty with provisional stenting. Coronary angioplasty is a safe and effective therapeutic procedure in selected dialysis patients with culprit lesions accessible to stenting. However, the one year survival is reduced in this high risk population.

Long-term outcome of coronary balloon angioplasty in diabetic patients

Diabetes is recognised to increase morbidity and mortality after coronary revascularization. We compared clinical outcomes in mean 5-year-long follow-up of coronary balloon angioplasty in diabetic and non-diabetic patients. We studied 621 patients undergoing elective angioplasty from 1987 to 1996. There were 60 (9.7%) patients with diabetes who were compared with 561 non-diabetic patients. Diabetics were older, more often obese, less frequently were current smokers, and less frequently had hypercholesterolaemia. Diabetic patients in comparison with non-diabetics had lower ejection fraction and more frequently had angioplasty of complex (B2 or C) lesions, but there were no differences between both groups in the other clinical and angiographic risk factors. Clinical success of angioplasty, as well as complications rate were similar in both groups. In follow-up restenosis occurred more frequently in diabetics (46.3 vs. 32.2%, P=0.03), resulting in significantly higher re-intervention rate (50.0 vs. 35.4%, P=0.03). Especially diabetic patients were more frequently referred to CABG (20.4 vs. 9. 9%, P=0.02). There were no significant differences in deaths (1.9 vs. 2.8%) and myocardial infarction (3.7 vs. 4.4%). Diabetics presented worse CCS status at the end of observation (Class 0 and I - 61.1 vs. 74.4%, P=0.037). Angioplasty proved to be a safe procedure in diabetic patients. Despite higher restenosis and re-intervention rate in diabetics, mortality as well as myocardial infarction rate was the same in both groups during mean 5-year follow-up.

Detection of coronary restenosis by exercise electrocardiography thallium-201 perfusion imaging and coronary angiography in asymptomatic patients after percutaneous transluminal coronary angioplasty

Noninvasive detection of restenosis in patients remaining asymptomatic after percutaneous transluminal coronary angioplasty (PTCA) remains a major clinical problem. The value of exercise electrocardiography (ECG) and exercise-redistribution thallium-201 single-photon emission computed tomography (SPECT) in detecting restenosis in such patients remains uncertain. Discordances between these tests and coronary angiography is a common situation. We studied 179 consecutive patients remaining asymptomatic after successful PTCA (208 vessels), who underwent 6 +/- 2 months of exercise ECG, SPECT, and coronary angiography. We sought to assess the diagnostic value of the noninvasive tests compared with coronary angiography, and identify the determinants of discordances between the tests. Restenosis (diameter stenosis >50%) was detected in 39% of patients and in 37% of vessels. The overall sensitivity, specificity, and accuracy for exercise ECG and SPECT in detecting restenosis in individual vessels were, respectively, 53% versus 63% (p = 0.06), 59% versus 77% (p = 0.0001), and 57% versus 72% (p = 0. 0001). On multivariate analysis, positive exercise ECG was associated with higher heart rate response (p = 0.02), incomplete revascularization (p = 0.004), and angiographic restenosis (p = 0. 03), whereas positive SPECT was associated with incomplete revascularization (p = 0.02), infarct-related artery PTCA (p = 0.01), and angiographic restenosis (p = 0.0001). Accuracies of the 2 tests were not significantly different in patients with incomplete revascularization or PTCA of an infarct-related vessel. Overall, SPECT is more accurate than exercise ECG in detecting asymptomatic restenosis. Nevertheless, incomplete revascularization and PTCA of an infarct-related artery could cause reversible perfusion defects regardless of restenosis, reducing the diagnostic value of SPECT in such patients.

Restenosis, late vessel occlusion and left ventricular function six months after balloon angioplasty in diabetic patients

OBJECTIVES

We studied angiographic outcome and its predictors after traditional coronary balloon angioplasty in diabetics. We further examined whether changes in ejection fraction were influenced by the status of the dilated site(s) at follow-up.

BACKGROUND

Recent studies have suggested that diabetics have a particularly poor outcome after balloon angioplasty. The reasons for this observation are not known.

METHODS

We investigated procedural and six-month angiographic outcome, analyzed by quantitative coronary angiography, and left ventricular function in 485 consecutive diabetics (627 lesions) treated by balloon angioplasty without stent implantation.

RESULTS

The procedure was successful in 455 (94%) patients; angiographic follow-up was available in 377 patients (83%). At follow-up, the rates of restenosis and total occlusion were 62% and 13%, respectively. Five independent predictors of restenosis were identified: the presence of organ damage, a saphenous vein graft (SVG) angioplasty, a bifurcation lesion, a Thrombolysis in Myocardial Infarction (TIMI) flow <3 preprocedure and the degree of residual stenosis. Four independent predictors of vessel occlusion were identified: treatment with insulin, a SVG angioplasty, a TIMI flow <3 preprocedure and the degree of residual stenosis after angioplasty. Late vessel occlusion at angioplasty site(s) was observed in 15% of patients, ranging from 11% for a one-site procedure to 37% for a three-site procedure. This complication was associated with a decrease in ejection fraction at follow-up (-6.2 +/- 9.9%, p = 0.0001), whereas no significant change was observed in patients without occlusion.

CONCLUSIONS

This study shows that late vessel occlusion is a frequent mode of restenosis in diabetic patients and is associated with a significant decrease in ejection fraction. This could partly explain the poor long-term clinical outcome reported in such patients after traditional balloon angioplasty.

Incidence and predictors of target vessel revascularization following percutaneous transluminal coronary angioplasty: a report from the National Heart, Lung, and Blood Institute Percutaneous Transluminal Coronary Angioplasty Registry

We sought to determine the rate of target vessel revascularization (TVR) after percutaneous transluminal coronary angioplasty (PTCA) and to determine factors that predispose to its occurrence. The 10-year outcome of 2,262 patients in the National Heart, Lung, and Blood institute PTCA Registry was analyzed to determine the incidence and characterize predictors of TVR. TVR was performed in 30.4% of patients. Male gender (relative risk [RR] 1.26; p <0.05), diabetes (RR 1.57; p <0.001), multiple discrete lesions (RR 1.38, p <0.01), diffuse lesions (RR 1.27; p <0.05), and calcium at the lesion site (RR 1.25; p <0.05) were predictors for TVR. TVR was performed early (< or = 1 year) in 18.3% and late (> 1 year) in 12.2%. Age > or = 65 years (RR 1.24; p <0.05), congestive heart failure (RR 1.70; p <0.05), acute coronary insufficiency (RR 1.28; p <0.05), and left anterior descending lesion location (RR 1.34, p <0.01) were significant predictors of early versus late TVR by multivariate analysis. Coronary artery bypass grafting (CABG) rather than PTCA was the TVR procedure in 21% of patients undergoing early TVR and 58% of those undergoing late TVR. Significant independent predictors of CABG as the TVR procedure were multivessel disease (RR 1.97; p <0.001), presence of collateral vessels (RR 1.81; p <0.05), diffuse (RR 1.89; p <0.01), or occluded (RR 1.82; p <0.05) target lesions, and a greater residual stenosis after the initial PTCA (RR 1.19; p <0.001). Age > or = 65 years (RR 0.65; p <0.05) conferred a lower risk for CABG.

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.

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.

Multivessel Palmaz-Schatz stenting: early results and one-year outcome

OBJECTIVES

To determine whether the benefits outlined in Background might extend to patients with multivessel disease, we examined the short- and long-term outcome of multivessel Palmaz-Schatz stenting.

BACKGROUND

Percutaneous transluminal coronary angioplasty (PTCA) has become the dominant treatment for most patients with single-vessel coronary artery disease and has emerged as an alternative treatment for selected patients with multivessel coronary artery disease. Although multivessel angioplasty has excellent early results and low procedural complication rates, long-term outcome is tempered by the frequent need for repeat revascularization. In patients with single-vessel coronary artery disease, Palmaz-Schatz stenting has been shown to have a higher success rate and a lower restenosis rate than conventional PTCA.

METHODS

A total of 103 patients (mean age 64 +/- 11 years, 78 men and 25 women) underwent stenting of 212 vessels (saphenous vein graft [53%], left anterior descending coronary artery [20%], left circumflex artery [12%] and right coronary artery [15%]). In 88 patients (85%), multivessel stenting was performed during the same procedure, whereas the remaining 15 patients (15%) had staged multivessel stenting within 1 week of the index stent. Stenting involved only native coronary arteries in 33 patients and only vein grafts in 51 patients.

RESULTS

Angiographic success was achieved in 102 patients (99%). Major complications developed in three patients: one patient died, and two patients had Q wave myocardial infarction, with no emergency coronary artery bypass graft surgery or stent thrombosis. Eleven additional patients (11%) developed non-Q wave myocardial infarction, and nine patients (9%) had local vascular complications requiring surgical repair. Clinical follow-up was available in all patients at a mean of 13 +/- 8 months. At 1 year, survival was 98%, with an event-free survival rate of 80%, reflecting predominantly repeat revascularization (17% overall, with 9% target site revascularization). Multivessel native coronary stenting resulted in a higher event-free survival rate and a lower probability of repeat revascularization than did multivessel saphenous vein graft stenting.

CONCLUSIONS

In selected patients, multivessel Palmaz-Schatz stenting is technically feasible and carries both excellent early results and favorable 1-year clinical outcome.

Analysis of effect of two concurrent ischaemic zones on left ventricular function

Left ventricular (LV) function due to two concurrent ischaemic zones (IZs) is investigated using a cardiovascular system model. The model comprises a three-compartment LV, the venous return and the arterial system. Haemodynamic responses of the LV to changes in the IZ size and myocardial contraction timings are explored. Results show that the greater the degree of asynschonisation is between the normal zone and the IZ, and the larger the ischaemic size, the more severe the LV dysfunction. Pre-load augmentation improves LV function. Model-predicted features are consistent with reported observations associated with myocardial ischaemia. The extent of the usefulness and limitations of this model is also discussed.

Coronary angioplasty in diabetic patients. The National Heart, Lung, and Blood Institute Percutaneous Transluminal Coronary Angioplasty Registry

BACKGROUND

Patients with diabetes mellitus are at increased risk of cardiovascular disease. To date, the baseline status and subsequent outcomes of diabetic coronary angioplasty (percutaneous transluminal coronary angioplasty, or PTCA) patients with advanced atherosclerotic disease and with procedures performed across North America have not been well characterized.

METHODS AND RESULTS

Data on baseline clinical and angiographic characteristics and short- and long-term outcomes of 281 diabetic and 1833 nondiabetic PTCA patients in the multicenter National Heart, Lung, and Blood Institute 1985-1986 PTCA Registry were analyzed. Diabetic patients were older, were more likely to be female, and had more comorbid baseline conditions, triplevessel disease, and atherosclerotic lesions. Angiographic success and completeness of revascularization did not differ significantly, yet diabetic patients experienced more in-hospital death (women) and nonfatal myocardial infarction. Nine-year mortality was twice as high in diabetic patients (35.9% versus 17.9%). Similarly, 9-year rates of nonfatal myocardial infarction (29.0% versus 18.5%), bypass surgery (36.7% versus 27.4%), and repeat PTCA (43.7% versus 36.5%) were higher in diabetics than in nondiabetics. In multivariate analysis, diabetes remained a significant predictor of decreased 9-year survival and other untoward events.

CONCLUSIONS

Compared with nondiabetic PTCA patients, diabetic patients have more extensive and diffuse atherosclerotic disease. Despite similar probability of angiographic success, diabetic patients are more likely to suffer in-hospital death(women) and nonfatal myocardial infarction. Long-term survival and freedom from myocardial infarction and coronary revascularization is also reduced in diabetic PTCA patients. Whether PTCA or coronary bypass surgery is more suitable for these patients is currently under investigation.

Computer modeling of non-adjacent regional ischemic zones on ventricular function

Multiple regional myocardial ischemia that leads to depressed left ventricular (LV) function is commonplace. Quantitative analysis of the hemodynamic consequences, however, has been limited. We investigated this aspect using a novel computer model of the cardiovascular system. The model consists of an LV with two ischemic zones (IZs) and a normal zone (NZ), the preload, and the arterial system afterload. The IZ size and activation timing could be altered. Results show that the greater the size and activation asynchronization between NZ and IZ, the more severe the LV dysfunction. Increased preload during ischemia improved LV function. This computer model predicts features that agree well with reported experimental observations and is particularly useful for myocardial ischemic function analysis.

Association between prior cytomegalovirus infection and the risk of restenosis after coronary atherectomy

BACKGROUND

Restenosis occurs commonly after coronary angioplasty and atherectomy, but the causes of restenosis are poorly understood. Recently, it has been found that cytomegalovirus (CMV) DNA is present in restenotic lesions from atherectomy specimens. This and other evidence suggest that CMV may have a role in the process of restenosis.

METHODS

We prospectively studied 75 consecutive patients undergoing directional coronary atherectomy for symptomatic coronary artery disease. Before atherectomy was performed, we measured blood levels of anti-CMV IgG antibodies to determine whether previous exposure to CMV increased the risk of restenosis, as determined by coronary angiography performed six months after atherectomy.

RESULTS

After atherectomy, the mean (+/- SD) minimal luminal diameter of the target vessel was greater in the 49 patients who were seropositive for CMV than in the 26 patients who were seronegative (3.18 +/- 0.51 mm vs. 2.89 +/- 0.45 mm, P=0.01). After six months, however, the seropositive patients had a greater reduction in the luminal diameter (1.24 +/- 0.83 mm vs. 0.68 +/- 0.69 mm, P = 0.003), resulting in a significantly higher rate o restenosis in the seropositive patients (43 percent vs. 8 percent, P = 0.002). In a multivariable logistic-regression model, CMV seropositivity and the CMV titer were independently predictive of restenosis (odds ratios, 12.9 and 8.1, respectively). There was no evidence of acute infection, since the titer of anti-CMV IgG antibodies did not increase over time and tests for anti-CMV IgM antibodies were negative in all patients.

CONCLUSIONS

Prior infection with CMV is strong independent risk factor for restenosis after coronary atherectomy. If confirmed, these findings may help identify patients at risk for restenosis.