Coronary angioplasty versus left internal mammary artery grafting for isolated proximal left anterior descending artery stenosis

A prospective randomized trial comparing stenting to internal mammary artery grafting for proximal, isolated de novo left anterior coronary artery stenosis: the SIMA trial. Stenting vs Internal Mammary Artery

OBJECTIVE

To compare coronary artery bypass grafting (CABG) with percutaneous transluminal coronary angioplasty (PTCA) in patients with proximal, isolated de novo left anterior descending coronary artery disease and left ventricular ejection fraction of 45%.

PATIENTS AND METHODS

In the multicenter Stenting vs Internal Mammary Artery (SIMA) study, patients were randomly assigned to PTCA and stent implantation or to CABG (using the internal mammary artery). The primary clinical composite end point was event-free survival, including death, myocardial infarction, and the need for additional revascularization. Secondary end points were functional class, antianginal treatment, and quality of life. Analyses were by intention to treat.

RESULTS

Of 123 patients who accepted randomization, 59 underwent CABG, and 62 were treated with stent implantation (2 patients were excluded because of protocol violation). At a mean +/- SD follow-up of 2.4+/-0.9 years, a primary end point had occurred in 19 patients (31%) in the stent group and in 4 (7%) in the CABG group (P<.001). This significant difference in clinical outcome is due to a higher incidence of additional revascularization in the stent group, the incidence of death and myocardial infarction being similar (7% vs 7%, respectively; P=.90). The functional class, need for antianginal drug, and quality-of-life assessment showed no significant differences.

CONCLUSIONS

Both stent implantation and CABG are safe and highly effective treatments to relieve symptoms in patients with isolated, proximal left anterior descending coronary artery stenosis. Both are associated with a low and comparable incidence of death and myocardial infarction. However, similar to PTCA alone, a percutaneous approach using elective stent placement remains hampered by a higher need for repeated intervention because of restenosis.

[Myocardial revascularization of the anterior descending artery with the classical technic of mammary anastomosis]

INTRODUCTION AND OBJECTIVES

To establish the results obtained with the classical technique of mammary anastomosis of the anterior descending artery.

MATERIALS AND METHODS

Between January 1982 and July 1997, 154 patients received an anastomosis of the left internal mammary artery to the left anterior descending coronary artery with use of the classical technique (sternotomy and extracorporeal circulation).

RESULTS

There was no operative mortality in our group, nor paraoperational myocardial infarction, nor cephalic vascular accidents. One (0.6%) patient had sternal wound infection, and another (0.6%) required another reoperation for postoperational bleeding. All (100%) were followed-up from 3-183 months (average 64. 4 months). Actuarial global survival at 5, 10 and 15 years was 95.6%+/-2.1; 92.1%+/-4 and 85.5+/- 7.5 respectively, and the actuarial probability of being free from cardiac death was 99%+/-0.9; 99% and 99%. The actuarial probability of being free from myocardial infarction was 99%+/-0.9; 99%+/-0.9 and 99%; and from angina was 95%+/-2.2; 86.9%+/-4.9 and 74.5%+/-12.2 at 5, 10 and 15 years.Finally, the actuarial probability of being free from reoperation was 99%+/-0.9; 99%; 99% and from angioplasty 96.9%+/-1.7; 91.4%+/-4.1; 91.4%+/-4.1 at 5, 10 and 15 years, respectively. The average hospital charges in the last 10% of the patients was U$ 6.200.

CONCLUSIONS

Revascularization of the left anterior descending with the left internal mammary artery and the classical technique (sternotomy and extracorporeal circulation) is a safe, minimal risk, effective, long lasting and cost efficient procedure with excellent results at 10 and 15 years.

[The practical clinical guidelines of the Sociedad Española de Cardiología on interventional cardiology: coronary angioplasty and other technics]

Interventional cardiology has had an extraordinary expansion in last years. This clinical guideline is a review of the scientific evidence of the techniques in relation to clinical and anatomic findings. The review includes: 1. Coronary arteriography. 2. Coronary balloon angioplasty. 3. Coronary stents. 4. Other techniques: directional atherectomy, rotational atherectomy, transluminal extraction atherectomy, cutting balloon, laser angioplasty and transmyocardial laser and endovascular radiotherapy. 5. Platelet glycoprotein IIb/IIIa inhibitors. 6. New diagnostic techniques: intravascular ultrasound, coronary angioscopy, Doppler and pressure wire. For the recommendations we have used the classification system: class I, IIa, IIb, III like in the guidelines of the American College of Cardiology and the American Heart Association.

[The practical clinical guidelines of the Sociedad Española de Cardiología on coronary surgery]

Surgery in coronary disease, including myocardial revascularization and the surgery of mechanical complications of acute myocardial infarction, has shown to improve the symptoms, quality of life and/or prognosis in certain groups of patients. The expected benefit in each patient depend on many well-known factors among which the appropriateness of the indication for surgery is fundamental. The objective of these guidelines is to review current indications for cardiac surgery in patients with coronary heart disease through an evaluation of the degree of evidence of effectiveness in the light of current knowledge (systematic review of bibliography) and expert opinion gathered from various reports. Indications and the degree of recommendation for conventional coronary artery bypass grafting have been established for each of the most frequent anatomo-clinical situations defined by clinical symptoms (stable angina, unstable angina and acute myocardial infarction) as well as by left ventricular function and extend of coronary disease. Furthermore, the subgroups with the greatest surgical risk and stratification models are described to aid the decision making process. Also we analyse the rational basis and indication for the new surgical techniques such as minimally invasive coronary surgery and total arterial revascularization. Finally, the indication and timing of surgery in patients with mechanical complications of acute myocardial infarction are considered.

Ten-year outcome after coronary angioplasty in patients with single-vessel coronary artery disease and comparison with the results of the Coronary Artery Surgery Study (CASS)

The 10-year results of randomized trials comparing percutaneous transluminal coronary angioplasty (PTCA) in patients with single-vessel coronary artery disease (CAD) with coronary artery bypass grafting (CABG) and medical treatment are not available yet. The aim of this evaluation was to compare our 10-year follow-up results after PTCA in patients with single-vessel CAD with the 10-year follow-up results after CABG and medical treatment in the Coronary Artery Surgery Study (CASS) trial. We evaluated the clinical outcome of 509 patients with single-vessel CAD 10 years after coronary angioplasty. The data were compared with the results of 214 patients with single-vessel CAD after CABG or medical treatment from the CASS trial. End points were defined as death and myocardial infarction. Statistical evaluation was performed by life-table analysis and 2-sided Fisher's exact test. The rate of survival was 86% 10 years after PTCA compared with 85% after CABG and 82% after medical treatment in patients from the CASS trial (p = NS). Survival free from myocardial infarction was 77% after coronary angioplasty, 70% after CABG, and 72% after medical treatment (p = NS). Thus, in patients with single-vessel CAD, infarct-free survival 10 years after coronary angioplasty compared favorably with the results after bypass surgery or medical treatment from the CASS trial.

Short- and long-term follow-up after coronary bypass grafting for single-vessel coronary artery disease

Short-term outcome and 10-year clinical outcome were reviewed in 114 consecutive patients after coronary artery bypass grafting (CABG) for single-vessel coronary artery disease (CAD). Gated equilibrium radionuclide cineangiography was performed soon after CABG in all cases, and revealed very good early graft patency rates. There was no perioperative mortality, and very low morbidity. During follow-up there were seven late deaths, two from cardiac disease and five from non-cardiac causes. Cumulative survival at 10 years was 93%. Cumulative freedom from additional cardiac invasive procedures was 96%, 93% and 80% at 1, 5, and 10 years, respectively, and cumulative freedom from angina was 93%, 80% and 73%. Conventional single-vessel CABG thus can be safely performed, with minimal postoperative morbidity and no mortality, providing good long-term relief of angina and circumventing need for additional invasive procedures.

Myocardial "hybrid" revascularisation with minimally invasive direct coronary artery bypass grafting combined with coronary angioplasty: preliminary results of a multicentre study

OBJECTIVE

To expand the benefits of the minimally invasive direct coronary artery bypass (MIDCAB) concept to patients with multivessel disease, a hybrid procedure combining surgical revascularisation of the left anterior descending artery with interventional procedures for additional coronary lesions has recently been introduced. Preliminary results in patients undergoing this hybrid procedure are presented.

DESIGN AND PATIENTS

Since December 1996, 35 patients (29 male, 6 female, mean (SD) age 56.7 (17) years) underwent a hybrid revascularisation performed as a primary MIDCAB procedure for grafting of the left anterior descending artery with the left internal mammary artery, followed by staged angioplasty and stenting of additional coronary lesions.

RESULTS

After MIDCAB grafting the postoperative course was uneventful in all patients. Coronary reangiography after a median of seven days revealed patent and functioning left internal mammary artery grafts in all patients. Applying subsequent percutaneous transluminal coronary angioplasty and occasional stenting (n = 14), a total of 47 lesions were treated successfully. Procedure related complications did not occur. All patients remained free from angina and no stress ECG changes were recorded.

CONCLUSIONS

The preliminary results of this hybrid approach to myocardial revascularisation suggest that this is a safe and effective procedure for complete revascularisation in selected patients with multivessel disease. Elderly and reoperative patients with significant comorbidity may benefit especially from such hybrid procedures by avoiding cardiopulmonary bypass and mid sternotomy.

Five-Year Follow-Up of the Medicine, Angioplasty, or Surgery Study (MASS)

Background —Although coronary angioplasty and myocardial bypass surgery are routinely used, there is no conclusive evidence that these interventional methods offer greater benefit than medical therapy alone. This study is intended to evaluate, in a prospective, randomized, and comparative analysis, the benefit of the 3 current therapeutic strategies for patients with stable angina and single proximal left anterior descending coronary artery stenosis.

Methods and Results —In a single institution, 214 patients with stable angina, normal ventricular function, and severe proximal stenosis (>80%) on the left anterior descending artery were selected for the study. After random assignment, 70 patients were referred to surgical treatment, 72 to angioplasty, and 72 to medical treatment. The primary end points were the occurrence of acute myocardial infarction or death and presence of refractory angina. After a 5-year follow-up, these combined events were reported in only 6 patients referred to surgery as compared with 29 patients treated with angioplasty and 17 patients who only received medical treatment ( P =0.001). However, no differences were noted in relation to the occurrence of cardiac-related death in the 3 treatment groups ( P =0.622). No patient assigned to surgery needed repeat operation, whereas 8 patients assigned to angioplasty and 8 patients assigned to medical treatment required surgical bypass after the initial random assignment. Surgery and angioplasty reduced anginal symptoms and stress-induced ischemia considerably. However, all 3 treatments effectively improved limiting angina.

Conclusions —Bypass surgery for single-vessel coronary artery disease is associated with a lower incidence of medium-term and long-term events as well as fewer anginal symptoms than that found in the patients who underwent angioplasty or medical therapy. In this study, coronary angioplasty was only superior to medical strategies in relation to the anginal status. However, the 3 treatment regimens yielded a similar incidence of acute myocardial infarction and death. Such information should be useful when choosing the best therapeutic option for similar patients.

Clinical correlates of the initial and long-term cost of coronary bypass surgery and coronary angioplasty

BACKGROUND

Medical costs vary substantially among patients. Understanding the baseline factors that predict subsequent cost may allow better selection of therapy for individual patients. Understanding the postprocedure events that increase cost should help to improve efficiency and effectiveness of coronary revascularization.

METHODS

Data on 4-year costs were collected from patients randomly assigned to coronary angioplasty or bypass surgery as part of the BARI (Bypass Angioplasty Revascularization Investigation) trial. Regression models first examined factors known at the time of randomization that prospectively predicted initial procedure cost and long-term cost. Subsequent models tested the value of postrandomization events as explanatory variables for cost.

RESULTS

The independent baseline predictors of higher initial percutaneous transluminal coronary angioplasty cost included 3-vessel disease (+12%) and acute presentations (+22%), whereas the independent predictors of higher initial coronary artery bypass grafting cost included the number of comorbid conditions (+5% per condition) and female sex (+7%). The independent baseline predictors of 4-year cost included heart failure (+26%), diabetes (+22%), comorbidity (+10%), and angioplasty assignment in patients with 2-vessel disease (-15%). Postrandomization models showed higher initial and long-term costs were strongly correlated with the number of repeat revascularization procedures (+30% to +128%) and the occurrence of clinical complications (+8% to +131%).

CONCLUSIONS

Two-vessel disease identifies patients likely to have lower costs after angioplasty, whereas heart failure, comorbid conditions, and diabetes identify patients likely to accrue higher costs after either angioplasty or bypass surgery. Long-term costs can be potentially reduced by interventions that decrease procedural complications or reduce the need for repeat revascularization.

Five-year outcome in patients with isolated proximal left anterior descending coronary artery stenosis treated by angioplasty or left internal mammary artery grafting. A prospective trial

BACKGROUND

Percutaneous transluminal coronary angioplasty (PTCA) and coronary artery bypass surgery (CABG) improve the clinical status of patients with isolated proximal left anterior descending coronary artery stenosis. At 2 years, only additional revascularization was more frequently required after PTCA.

METHODS AND RESULTS

We monitored 134 patients randomized to PTCA (n=68) or CABG (n=66) for </=5 years. End points were death, myocardial infarction, need for additional revascularization, clinical status, and medical treatment. At 5 years, 6 patients (9%) had died in the PTCA group versus 2 (3%) in the CABG group (P=0.12). One patient in each group died of a cardiac cause. Myocardial infarction was more frequent after PTCA (15% versus 4%; P=0.0001), but Q-wave infarction was not (6% in the PTCA group versus 3% in the CABG group; P=0.8). Additional revascularization was required in 38% of patients in the PTCA group versus 9% in the CABG group (P=0.0001). Functional status was comparable, with 6% of patients after PTCA and 3% after CABG in functional class III or IV. Finally, after PTCA or CABG, 62% and 91% of patients, respectively, were free of events (P=0.0001).

CONCLUSIONS

The 5-year prognosis of patients with isolated proximal left anterior descending coronary artery stenosis is good. Both PTCA and CABG improve clinical status, but revascularization was needed more frequently after PTCA. There is an excess incidence of non-Q-wave myocardial infarction in the PTCA group that does not affect the vital or symptomatic outcome.

Appropriateness of referral of coronary angiography patients in Sweden. SECOR/SBU Project Group

OBJECTIVE

To evaluate the appropriateness of referral following coronary angiography in Sweden.

DESIGN

Prospective survey and review of medical records.

PATIENTS

Consecutive series of 2767 patients who underwent coronary angiography in Sweden between May 1994 and January 1995 and were considered for coronary revascularisation.

MAIN OUTCOME MEASURES

Percentage of patients referred for coronary artery bypass graft surgery (CABG) and percutaneous transluminal coronary angioplasty (PTCA) for indications that were judged necessary, appropriate, uncertain, and inappropriate by a multispecialty Swedish national expert panel using the RAND/University of California Los Angeles (UCLA) appropriateness method, and the percentage of patients referred for continued medical management who met necessity criteria for revascularisation.

RESULTS

Half the patients were referred for CABG, 25% for PTCA, and 25% for continued medical therapy. CABG was judged appropriate or necessary for 78% of patients, uncertain for 12% and inappropriate for 10%. For PTCA the figures were 32%, 30% and 38%, respectively. Two factors contributed to the high inappropriate rate. Many of these patients did not have "significant" coronary artery disease (although all had at least one stenosis > 50%) or they were treated with less than "optimal" medical therapy. While 96% of patients who met necessity criteria for revascularisation were appropriately referred for revascularisation, 4% were referred for continued medical therapy.

CONCLUSIONS

Using the RAND/UCLA appropriateness method and the definitions agreed to by the expert panel, which may be considered conservative today, it was found that 19% of Swedish patients were referred for coronary revascularisation judged inappropriate. Since some cardiovascular procedures evolve rapidly, the proportion of patients referred for inappropriate indications today remains unknown. Nevertheless, physicians should actively identify those patients who will and will not benefit from coronary revascularisation and ensure that they are appropriately treated.

[The clinical and angiographic evolution of dilated lesions in the proximal segment of the anterior descending coronary artery: stent versus balloon]

INTRODUCTION AND OBJECTIVES

The restenosis rate after coronary balloon angioplasty of lesions located in the proximal segment of the left anterior descending coronary artery is high, having been recommended elective stent implantation in order to improve the outcomes. The aim of this study was to analyze clinical, anatomic and angiographic factors related to the short-term outcome after angioplasty of severe lesions in the proximal segment of the left anterior descending artery, with and without stent implantation.

MATERIAL AND METHODS

We study 87 patients with severe stenosis (> or = 70%) of the proximal segment of left anterior descending artery treated successfully with angioplasty. In 54 patients (62%) a conventional balloon was used (group A) and in 33 (38%) a stent was implanted (group B).

RESULTS

Mean age of patients was 61.9 +/- 12 years old, 74% were male and angioplasty was performed because of unstable angina in 72%. At the end of the follow-up (mean 6.3 +/- 1.5 months), 21% of patients in group B had angina vs 54% in group A (p = 0.03). Group B patients experienced a lower restenosis rate (30% vs. 50%; p = 0.07) and less repeat angioplasty procedures (33% vs 21%; p = NS) than group A. These results were maintained independently of the vessel diameter (< 3 mm or > or = 3 mm) or when an optimal result (< 25%) after balloon angioplasty was obtained.

CONCLUSIONS

In our experience, stenting of lesions located in the proximal segment of the left anterior descending artery appears imply a better short-term clinical, angiographic outcome and a lower restenosis rate than lesions treated with conventional balloon angioplasty, even despite an optimal result after balloon angioplasty or independently of the vessel diameter. Future studies will be necessary to confirm these results.

Long-term results of RITA-1 trial: clinical and cost comparisons of coronary angioplasty and coronary-artery bypass grafting. Randomised Intervention Treatment of Angina

BACKGROUND

Percutaneous transluminal coronary angioplasty (PTCA) and coronary-artery bypass grafting (CABG) are both effective intervention strategies for patients with coronary heart disease. We report comparative long-term clinical and health-service cost findings for these interventions in the first Randomised Intervention Treatment of Angina (RITA-1) trial.

METHODS

1011 patients with coronary heart disease (45% single-vessel, 55% multivessel) were randomly assigned initial treatment strategies of PTCA or CABG. Information on clinical events, subsequent intervention, symptomatic status, exercise testing, and use of health-care resources is available for a median 6.5 years of follow-up. Analyses were by intention to treat.

FINDINGS

The predefined primary endpoint of death or nonfatal myocardial infarction occurred in 87 (17%) PTCA-group patients and 80 (16%) CABG-group patients (p=0.64). Similarly, there was no significant treatment difference in deaths alone (39 PTCA, 45 CABG), of which 46% were cardiac related. In both groups, the risk of cardiac death or myocardial infarction was more than five times higher in the first year than in subsequent years of follow-up. 26% of patients assigned PTCA subsequently also had CABG, and a further 19% required additional nonrandomised PTCA. Most of these reinterventions occurred within a year of randomisation, and from 3 years onwards the reintervention rate averaged 4% per year. In the CABG group the reintervention rate averaged 2% per year. The prevalence of angina was consistently higher in the PTCA group, with an absolute average 10% excess compared with the CABG group (p<0.001). Total health-service costs over 5 years showed no significant difference between initial strategies of PTCA and CABG (mean difference pounds sterling 426 [95% Cl -pounds sterling 383 to pounds sterling 1235]; p=0.30). The clinical and cost comparisons showed similar patterns for patients with single-vessel and multivessel disease.

INTERPRETATION

Initial strategies of PTCA and CABG led to similar long-term results in terms of survival and avoidance of myocardial infarction and to similar long-term health-care costs. Choice of approach, therefore, rests on weighing the more invasive nature of CABG against the greater risk of recurrent angina and reintervention over many years after PTCA.

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.

The role of myocardial revascularization preceding noncardiac surgery

Of about 6.7 million Americans who have coronary artery disease, approximately 700,000 undergo various noncardiac operations annually in the United States. Perioperative cardiac complications remain the leading cause of morbidity and mortality not related to the primary operative procedure; the mechanisms of perioperative ischemia and infarction are unclear. Currently, clinicians, using a combination of clinical and laboratory findings, can estimate the risk of noncardiac surgical procedures with a high degree of precision, but much less is known about the preferred approach to patient management after noninvasive risk stratification. Coronary angiography and revascularization are frequently recommended for those determined by functional tests to be at moderate and high risk, but the risks of revascularization are often substantially higher among these patients. No randomized, controlled trials exist to guide patient management. Quantitative decision analysis based on published nonrandomized data suggests that coronary angiography with selective myocardial revascularization should be performed to reduce the risk of noncardiac surgery only if the risk of noncardiac surgery is greater than 5% and the risk of coronary angiography with selective revascularization is less than 3%. On the other hand, if independent indications exist for myocardial revascularization, it should generally be performed before the noncardiac operation.

Pathophysiology and treatment of single-vessel coronary artery disease

The optimal treatment of patients with single-vessel coronary artery disease (CAD) and chronic stable angina is controversial. Therapeutic options include medical therapy with pharmacologic agents and/or coronary revascularization via surgery (coronary artery bypass grafting [CABG]), percutaneous transluminal coronary angioplasty (PTCA), and/or other transcatheter techniques. Early studies found no difference in survival between medical and surgical treatment of patients with single-vessel disease and chronic stable angina. Although PTCA has been shown to improve symptoms and quality of life in patients with single-vessel disease and severe symptoms, improvement in survival and prevention of future events are not established and multiple PTCA procedures or subsequent surgical treatment may be necessary. Medical therapy may be preferred in patients with mild or no symptoms. In patients with chronic stable angina, PTCA practice may not be consistent with current guidelines, particularly obtaining laboratory evidence of ischemia before the procedure. Stenoses that may lead to future coronary events cannot be accurately identified by angiography without evidence of ischemia or symptoms. Currently available comparative studies of patients with CAD do not reflect the impact of stent procedures and aggressive lipid lowering. Therefore, diagnostic and treatment options should be individualized in patients with single-vessel disease and chronic stable angina, and additional randomized trials are necessary to determine the optimal management of these patients.

Effect of pravastatin on angiographic restenosis after coronary balloon angioplasty. The PREDICT Trial Investigators. Prevention of Restenosis by Elisor after Transluminal Coronary Angioplasty

OBJECTIVES

This study sought to determine whether pravastatin affects clinical or angiographic restenosis after coronary balloon angioplasty.

BACKGROUND

Experimental data and preliminary clinical studies suggest that lipid-lowering drugs might have a beneficial effect on restenosis after coronary angioplasty.

METHODS

In a multicenter, randomized, double-blind trial, 695 patients were randomized to receive pravastatin (40 mg/day) or placebo for 6 months after successful balloon angioplasty. All patients received aspirin (100 mg/day). The primary angiographic end point was minimal lumen diameter (MLD) at follow-up, assessed by quantitative coronary angiography. A sample size of 313 patients per group was required to demonstrate a difference of 0.13 mm in MLD between groups (allowing for a two-tailed alpha error of 0.05 and a beta error of 0.20). To allow for incomplete angiographic follow-up (estimated lost to follow-up rate of 10%), 690 randomized patients were required. Secondary end points were angiographic restenosis rate (restenosis assessed as a categoric variable, > 50% stenosis) and clinical events (death, myocardial infarction, target vessel revascularization).

RESULTS

At baseline, clinical, demographic, angiographic and lipid variables did not differ significantly between groups. In patients treated with pravastatin, there was a significant reduction in total and low density lipoprotein cholesterol and triglyceride levels and a significant increase in high density lipoprotein cholesterol levels. At follow-up the MLD (mean +/- SD) was 1.47 +/- 0.62 mm in the placebo group and 1.54 +/- 0.66 mm in the pravastatin group (p = 0.21). Similarly, late loss and net gain did not differ significantly between groups. The restenosis rate (recurrence > 50% stenosis) was 43.8% in the placebo group and 39.2% in the pravastatin group (p = 0.26). Clinical restenosis did not differ significantly between groups.

CONCLUSIONS

Although pravastatin has documented efficacy in reducing clinical events and angiographic disease progression in patients with coronary atherosclerosis, this study shows that it has no effect on angiographic outcome at the target site 6 months after coronary angioplasty.

Minimally invasive coronary artery bypass grafting versus coronary angioplasty for isolated type C stenosis of the left anterior descending artery

BACKGROUND

Isolated stenosis of the left anterior descending coronary artery can be treated with medication, percutaneous transluminal coronary angioplasty, or coronary artery bypass grafting. Recently a new treatment has been developed, which is called minimally invasive direct coronary artery bypass grafting. This new treatment is a modification of the conventional bypass operation and is performed through a small anterolateral thoracotomy without cardiopulmonary bypass.

METHODS

To compare minimally invasive bypass with angioplasty, we evaluated in-hospital results and 1-year follow-up in 181 consecutive patients with isolated type C stenosis of the left anterior descending coronary artery between January 1995 and July 1996. Of these patients, 71 underwent minimally invasive bypass and 110 angioplasty. Preoperative characteristics were not significantly different between the two groups.

RESULTS

In-hospital death, periprocedural myocardial infarction, emergency reoperation by means of conventional coronary bypass grafting, use of an intraaortic balloon pump, and cerebrovascular accidents were not significantly different between the two groups. At 1-year follow-up, survival was not significantly different in the two groups (minimally invasive bypass 95.7% +/- 0.2% vs angioplasty 95.3% +/- 0.2%; p = 0.89), whereas freedom from repeated revascularization was significantly more common in the group undergoing minimally invasive bypass (bypass 96.9% +/- 0.2% vs angioplasty 67.6% +/- 0.5%; p < 0.001). This study shows that the need for repeated revascularization, and therefore the use of health care resources, is significantly less with minimally invasive bypass than with angioplasty in patients with isolated type C stenosis of the left anterior descending coronary artery.

A profile of candidates for repeat myocardial revascularization: implications for selection of treatment

OBJECTIVES

It is not known whether the results of randomized trials comparing coronary artery bypass grafting to percutaneous transluminal coronary angioplasty for initial revascularization apply to repeat revascularization in patients with prior bypass grafts. We studied the differences between the patients with prior bypass grafts referred for surgery or angioplasty to identify the clinical and angiographic characteristics that correlated best with either choice and to find clues that might aid in selecting one treatment over the other.

METHODS

Between 1992 and 1994, 870 patients underwent first isolated reoperation and 793 patients underwent first balloon angioplasty after a previous operation. A jeopardy score (0 to 8 points) was derived for each patient on the basis of the relative size of the ischemic territory. Clinical and angiographic data were analyzed for association with the revascularization strategy.

RESULTS

The following characteristics were more prevalent in the reoperation group: male sex, diabetes, hypertension, valvular disease, normocholesterolemia, and severe left ventricular systolic dysfunction; fewer functioning venous and arterial grafts; and a higher jeopardy score (p < 0.01 for all) than in the angioplasty group. A higher jeopardy score, diabetes, and a lower number of functioning arterial or venous grafts were strong, independent predictors of referral for reoperation (p < 0.01 for all). In hospital death and Q-wave infarction (p < 0.01 for both) were more frequent in the reoperation group.

CONCLUSIONS

Reoperation was the revascularization procedure of choice when larger regions of myocardium were in jeopardy. Angioplasty was more frequently chosen in the presence of a patent arterial graft to the left anterior descending coronary artery or multiple functioning bypass grafts. Reoperation was associated with a higher risk of in-hospital complications than angioplasty.

[Research methods in clinical cardiology (VII). Experimental studies in cardiology]

Experimental designs in clinical investigation are discussed in this article. Guideline examples have been used in the area of Cardiology using always the same one only one whenever possible. We have looked for a different perspective from what is generally used in the discussion of the general characteristics of experimental designs, and more specifically of clinical trials and we deal with the aspects of clinical trials which are usually ignored due to their marginal character. We also discuss those characteristics which differentiate clinical trials in respect to other designs and types of questions which are answered by clinical trials. And we finally discuss various aspects such as randomization and its various types (simple, block, stratified, pre-randomized) and variable types of evaluating the answers, masking and the problems in its maintenance, with certain kinds of designs, sample size, etc. There is a brief mention of two particular cases: factorial and cross over designs are both discussed, mentioning their strong and weak points. Likewise, we discuss community trials as another experimental design and examples are provided. Finally, we discuss aspects of criteria: such as, When to stop the trials? or Who are the results applicable to?, and we suggest points to take into consideration when these decisions are made.

A comparison of coronary-artery stenting with angioplasty for isolated stenosis of the proximal left anterior descending coronary artery

BACKGROUND

Randomized studies have shown that the use of coronary-artery stenting as the initial treatment for coronary stenosis is associated with a lower risk of restenosis than is standard coronary angioplasty. We prospectively investigated the efficacy of these two approaches in selected patients with isolated stenosis of the proximal left anterior descending coronary artery.

METHODS

A total of 120 patients with isolated stenosis of the proximal left anterior descending coronary artery were randomly assigned to stent implantation or standard coronary angioplasty. The primary clinical end points were the rate of procedural success (defined as residual stenosis of less than 50 percent and the absence of death, myocardial infarction, and the need for coronary-artery bypass surgery during the hospital stay) and the rate of event-free survival (defined as freedom from death, myocardial infarction, and the recurrence of angina) at 12 months. The angiographic end point was the rate of restenosis 12 months after the procedure.

RESULTS

The two treatment groups did not differ significantly with respect to demographic, clinical, or angiographic characteristics. The rates of procedural success were similar in the two groups of patients (95 percent in the stenting group vs. 93 percent in the angioplasty group, P = 0.98). The 12-month rates of event-free survival were 87 percent after stenting and 70 percent after angioplasty (P = 0.04). The rates of restenosis were 19 percent after stent implantation and 40 percent after angioplasty (P = 0.02).

CONCLUSIONS

In patients with symptomatic isolated stenosis of the proximal left anterior descending coronary artery, stenting had advantages over standard coronary angioplasty in that it was associated with both a lower rate of restenosis and a better clinical outcome.

Indications for coronary revascularisation: a Dutch perspective

OBJECTIVE

To assess the appropriateness of indications for coronary artery bypass graft (CABG) surgery and percutaneous transluminal coronary angioplasty (PTCA).

METHODS

A modified Delphi group judgement process with input from a panel of six interventional cardiologists and six cardiopulmonary surgeons. There was one clinician from each of the 12 tertiary referral heart centres in The Netherlands.

MAIN OUTCOME MEASURE

Ratings by panel members, on a 1 to 9 scale, of indications presented as a choice between two treatments (CABG v medical treatment, PTCA v medical treatment, and CABG v PTCA) for 1182 model cases. Each case represented a unique combination of clinical features in terms of symptoms, medical history, and results of tests. Ratings were analysed with respect to degree of agreement among panelists, degree of appropriateness of indications, and panel's preference for invasive or medical treatment.

RESULTS

The panel agreed on 58.6% and disagreed on 3.2% of the indications. The panel opted for invasive treatment in 48.2% and medical treatment in 22.8%, and had no clear preference for either method in 29.0% of the cases. When compared with medical treatment, CABG was more often rated appropriate than PTCA: 35.4% v 21.6% (P < 0.001). Panel scores depended on severity of anatomical disease. For instance, for 51.5% of the model cases with one-vessel disease not including the proximal left anterior descending artery, the panel preferred medical treatment to invasive treatment, while the latter was preferred in 18% of the cases. In cases with type C lesions, the panel frequently rated PTCA as inappropriate. Panel scores were also affected by nonclinical factors. Cardiologists and surgeons rated the procedure of their own specialty higher than the alternative invasive intervention.

CONCLUSIONS

The panel method yields logically consistent scores of the appropriateness of indications for carrying out medical procedures. It may be an aid in formulating clinical practice guidelines.

Medical care costs and quality of life after randomization to coronary angioplasty or coronary bypass surgery. Bypass Angioplasty Revascularization Investigation (BARI) Investigators

BACKGROUND

Randomized trials comparing coronary angioplasty with bypass surgery in patients with multivessel coronary disease have shown no significant differences in overall rates of death and myocardial infarction. We compared quality of life, employment, and medical care costs during five years of follow-up among patients treated with angioplasty or bypass surgery.

METHODS

A total of 934 of the 1829 patients enrolled in the randomized Bypass Angioplasty Revascularization Investigation participated in this study. Detailed data on quality of life were collected annually, and economic data were collected quarterly.

RESULTS

During the first three years of follow-up, functional-status scores on the Duke Activity Status Index, which measures the ability to perform common activities of daily living, improved more in patients assigned to surgery than in those assigned to angioplasty (P<0.05). Other measures of quality of life improved equally in both groups throughout the follow-up period. Patients in the angioplasty group returned to work five weeks sooner than did patients in the surgery group (P<0.001). The initial mean cost of angioplasty was 65 percent that of surgery ($21,113 vs. $32,347, P<0.001), but after five years the total medical cost of angioplasty was 95 percent that of surgery ($56,225 vs. $58,889), a difference of $2,664 (P = 0.047). The five-year cost of angioplasty was significantly lower than that of surgery among patients with two-vessel disease ($52,930 vs. $58,498, P<0.05), but not among patients with three-vessel disease ($60,918 vs. $59,430). After five years of follow-up, surgery had an overall cost-effectiveness ratio of $26,117 per year of life added, but unacceptable ratios of $100,000 or more per year of life added could not be excluded (P=0.13). Surgery appeared particularly cost effective in treating diabetic patients because of their significantly improved survival.

CONCLUSIONS

In patients with multivessel coronary disease, coronary-artery bypass surgery is associated with a better quality of life for three years than coronary angioplasty, after the initial morbidity caused by the procedure. Coronary angioplasty has a lower five-year cost than bypass surgery only in patients with two-vessel coronary disease.

Quality of life, employment status, and anginal symptoms after coronary angioplasty or bypass surgery. 3-year follow-up in the Randomized Intervention Treatment of Angina (RITA) Trial

BACKGROUND

The Randomized Intervention Treatment of Angina (RITA) trial compares initial policies of percutaneous transluminal coronary angioplasty (PTCA) and coronary artery bypass graft surgery (CABG) in 1011 patients with angina. This report assesses the impact of these revascularization procedures on angina, quality of life (according to the Nottingham Health Profile), and employment over 3 years of follow-up.

METHODS AND RESULTS

Both interventions produced marked improvement in all quality-of-life dimensions (energy, pain, emotional reactions, sleep, social isolation, and mobility) and seven aspects of daily living. Patients with angina at 2 years had more quality-of-life impairment than angina-free patients, whose perceived health was similar to population norms. This reflects the close link at baseline between angina grade and quality of life. The slightly greater impairment of quality of life in PTCA compared with CABG patients is a result of their significantly higher chances of having angina, especially after 6 months. Employment status was investigated mainly for men < or = 60 years old. PTCA patients returned to work sooner (40% at 2 months compared with 10% of CABG patients), but the latter caught up by 5 months. After 2 years, 22% and 26% of CABG and PTCA patients, respectively, were not working for cardiac reasons. Patients with angina at 2 years were much more likely to be unemployed than those without.

CONCLUSIONS

The impact of angina on quality of life and unemployment is greatly alleviated by PTCA or CABG. Angina is avoided more successfully with CABG, but PTCA offers a speedier return to work. Both intervention strategies then produce similar benefits for quality of life and employment over several years.

Ten-year follow-up of percutaneous transluminal coronary angioplasty for proximal left anterior descending coronary artery stenosis in 351 patients

OBJECTIVES

We sought to evaluate the short- and long-term results of balloon angioplasty for stenoses in the proximal left anterior descending coronary artery.

BACKGROUND

Both the supposedly high rate of acute complications and relatively poor long-term results of balloon angioplasty for stenoses in the proximal left anterior descending coronary artery have led to a search for alternative interventional techniques.

METHODS

We analyzed the success rates and long-term follow-up results in 351 consecutive patients who underwent balloon angioplasty for stenosis of the left anterior descending coronary artery proximal to its first side branch. The power of the study was >80% in detecting a difference of 9% in the proportion of patients who survived at 10 years, assuming an 80% survival rate in the control group.

RESULTS

There were 60 ostial and 291 nonostial stenoses. Follow-up lasted a median of 85 months (range 0 to 137) and was 100% complete. The angiographic success rate was 90.9%. The clinical success rate was 86.3%. Nine patients (2.6%) died, 17 (4.8%) needed emergency coronary artery bypass graft surgery, and 10 (2.8%) developed a myocardial infarction. Several patients had subsequent complications. The success and complication rates were not significantly different for patients with ostial and nonostial stenoses. Ten years after balloon angioplasty, freedom from mortality was 80%, freedom from cardiac death was 87%, freedom from myocardial infarction was 84%, freedom from vessel-related reinterventions was 66%, and freedom from angina pectoris was 33%. There were more reinterventions for ostial stenoses, with a 1-year relative risk of ostial versus nonostial stenoses for related reinterventions of 1.7 (95% confidence interval 1 to 2.8, p = 0.049).

CONCLUSIONS

More than 10 years ago, balloon angioplasty for stenoses in the proximal left anterior descending coronary artery, either ostial or nonostial, had a high success rate. Although the long-term results are satisfactory, ostial stenoses are associated with a higher early clinical restenosis rate requiring more reinterventions.

Cost-effective management of chronic stable angina

In certain patients with stable angina who are at moderate to high risk, coronary bypass surgery or coronary angioplasty are the therapeutic options of choice. However, in selected other patients the use of anti-ischemic drug therapy and secondary prevention reduce episodes of myocardial ischemia and result in a good long-term prognosis. Factors affecting management include the extent of coronary disease, the magnitude of cardiac symptoms, the severity of myocardial ischemia and of left ventricular function. Based upon these and other clinical characteristics, patients can be divided into low-, moderate-, or high-risk categories for morbidity and mortality. Patients at high risk are more likely to be selected for myocardial revascularization and patients at low risk are often treated with medical therapy, at least initially. Based on the available cost-effectiveness data, medical therapy or coronary angioplasty are the preferred initial strategies for low-risk coronary disease, whereas coronary bypass surgery (CABG) is recommended for many high-risk patients, particularly for those with triple-vessel disease and impaired left ventricular function or ischemia at a low workload. CABG is cost-effective for patients with severe angina and left main coronary artery disease and also for patients with mild angina and triple-vessel disease. Coronary angioplasty is cost-effective for patients with severe angina, and single- or multivessel disease. In patients with lesser symptoms and mild coronary disease, the cost effectiveness of myocardial revascularization therapy is less likely to be as good as it is in patients with more extensive disease and severe symptoms.

Care of acute myocardial infarction by noninvasive and invasive cardiologists: procedure use, cost and outcome

OBJECTIVES

This study sought to determine how noninvasive and invasive cardiologists may differ in the hospital care of patients with acute myocardial infarction.

BACKGROUND

Scant information exists regarding the effect of noninvasive and invasive cardiology subspecialization on invasive cardiac procedural use, cost and outcome in the care of patients with acute myocardial infarction.

METHODS

This study analyzed a prospective cohort of 292 patients admitted to an urban tertiary care hospital from the emergency room under the care of noninvasive or invasive cardiologists. Clinical characteristics; hospital course, including management, utilization of diagnostic coronary angiography and percutaneous transluminal coronary angioplasty; direct hospital costs; length of hospital stay; and post-hospital discharge follow-up data were collected by a prospective data base instrument.

RESULTS

Despite similar clinical characteristics, extent and severity of coronary artery disease and utilization of diagnostic coronary angiography in the two groups of patients, those under the care of an invasive cardiologist were significantly more likely to undergo coronary angioplasty than those under the care of a noninvasive cardiologist. The direct hospital costs and length of stay of the noninvasive and invasive group patients who underwent coronary angioplasty were similar, although overall the direct hospital costs and length of stay were higher for the invasive than for the noninvasive group patients.

CONCLUSIONS

Noninvasive and invasive cardiologists differ in their rate of utilization of coronary angioplasty in similar patients with acute myocardial infarction.

The Medicine, Angioplasty or Surgery Study (MASS): a prospective, randomized trial of medical therapy, balloon angioplasty or bypass surgery for single proximal left anterior descending artery stenoses

OBJECTIVES

This study sought to evaluate, in a prospective and randomized trial, the relative efficacies of three possible therapeutic strategies for patients with a single severe proximal stenosis of the left anterior descending coronary artery and stable angina.

BACKGROUND

Although percutaneous transluminal coronary angioplasty and coronary artery bypass surgery are often performed in patients with a single proximal stenosis of the left anterior descending coronary artery, it is unclear whether revascularization offers greater clinical benefit than medical therapy alone.

METHODS

At a single center, 214 patients with stable angina, normal ventricular function and a proximal stenosis of the left anterior descending coronary artery > 80% were randomly assigned to undergo mammary bypass surgery (n = 70), balloon angioplasty (n = 72) or medical therapy alone (n = 72). Angioplasty had to be considered technically feasible in every case. The predefined primary study end point was the combined incidence of cardiac death, myocardial infarction or refractory angina requiring revascularization.

RESULTS

At an average follow-up period of 3 years, a primary end point had occurred in only 2 patients (3%) assigned to bypass surgery compared with 17 assigned to angioplasty (24%) and 12 assigned to medical therapy (17%) (p = 0.0002, angioplasty vs. bypass surgery; p = 0.006, bypass surgery vs. medical treatment; p = 0.28, angioplasty vs. medical treatment, all by log-rank test). There was no difference in mortality or infarction rates among the groups. However, no patient allocated to bypass surgery needed revascularization, compared with eight and seven patients assigned, respectively, to coronary angioplasty and medical treatment (p = 0.019). Both revascularization techniques resulted in greater symptomatic relief and a lower incidence of ischemia on the treadmill test; however, all three strategies eventually resulted in the abolition of limiting angina.

CONCLUSIONS

The more aggressive therapeutic approach with initial bypass surgery for patients with a single severe proximal stenosis of the left anterior descending coronary artery is associated with a lower incidence of medium-term adverse events than coronary angioplasty or medical treatment. However, all three strategies resulted in a similar incidence of death and infarction during an average follow-up period of 3 years. This information should be taken into consideration when physicians and patients make therapeutic choices in this setting.

A meta-analysis of randomized trials comparing coronary artery bypass grafting with percutaneous transluminal coronary angioplasty in multivessel coronary artery disease

We performed a meta-analysis of randomized trials that compared percutaneous transluminal coronary angioplasty (PTCA) with coronary artery bypass graft (CABG) surgery in patients with multivessel coronary artery disease. The outcomes of death, combined death, and nonfatal myocardial infarction (MI), repeat revascularization, and freedom from angina were analyzed. The overall risk of death and nonfatal MI was not different over a follow-up of 1 to 3 years (CABG:PTCA odds ratio [OR] 1.03, 95% confidence interval 0.81 to 1.32, p = 0.81). Patients randomized to CABG tended to have a higher risk of death or MI in the early, periprocedural period (OR 1.33, p = 0.091), but a lower risk in subsequent follow-up (OR 0.74, p = 0.093). CABG patients were much less likely to undergo another revascularization procedure (p < 0.00001), and were more likely to be angina free (OR 1.57, p < 0.00001). Thus, CABG and PTCA patients have similar overall risks of death and nonfatal MI at 1 to 3 years of follow-up, but relative risk differences in mortality of up to 25% cannot be excluded. CABG patients have significantly less angina and less repeat revascularization than PTCA patients.

Meta-analysis of randomised trials comparing coronary angioplasty with bypass surgery

A patient with severe angina will often be eligible for either angioplasty (PTCA) or bypass surgery (CABG). Results from eight published randomised trials have been combined in a collaborative meta-analysis of 3371 patients (1661 CABG, 1710 PTCA) with a mean follow-up of 2.7 years. The total deaths in the CABG and PTCA groups were 73 and 79, respectively, with a relative risk (RR) of 1.08 (95% CI 0.79-1.50). The combined endpoint of cardiac death and non-fatal myocardial infarction occurred in 169 PTCA patients and 154 CABG patients (RR 1.10 [0.89-1.37]). Amongst patients randomised to PTCA 17.8% required additional CABG within a year, while in subsequent years the need for additional CABG was around 2% per annum. The rate of additional non-randomised interventions (PTCA and/or CABG) in the first year of follow-up was 33.7% and 3.3% in patients randomised to PTCA and CABG, respectively. The prevalence of angina after one year was considerably higher in the PTCA group (RR 1.56 [1.30-1.88]) but at 3 years this difference had attenuated (RR 1.22 [0.99-1.54]). Overall there was substantial similarity in outcome across the trials. Separate analyses for the 732 single-vessel and 2639 multivessel disease patients were largely compatible, though the rates of mortality, additional intervention, and prevalent angina were slightly lower in single vessel disease. The combined evidence comparing PTCA with CABG shows no difference in prognosis between these two initial revascularisation strategies. However, the treatments differ markedly in the subsequent requirement for additional revascularisation procedures and in the relief of angina. These results will influence the choice of revascularisation procedure in future patients with angina.

The invasive management of angina: issues for consumers and commissioners

OBJECTIVE

To review, from the purchaser's perspective, the current state of knowledge of techniques for investigation and treating coronary artery disease. The study was based on evidence from past and continuing randomised controlled trials (RCTs). CRITERIA FOR INCLUSION OF REPORTS: Articles listed on Medline (1990-3) with the keywords coronary disease, angina, and unstable angina (combined with surgery, economics, therapy, or drug therapy) and percutaneous transluminal coronary angioplasty (PTCA) and coronary artery bypass grafting (CABG) were included. Articles published before 1990 were obtained from two comprehensive literature reviews published by the Rand organisation in 1991 and from the papers obtained using the Medline search. A hand search of relevant journals published between July 1993 and June 1994 was also undertaken. Results from more recently published RCTs are included.

RESULTS

CABG provides improved angina relief compared with drug treatment and may prolong life in patients with more severe illness. PTCA is also better than drug treatment, but less so than CABG, and its cost advantages over CABG decrease with time. Repeat intervention for return of symptoms is more frequently required after PTCA, but increasing numbers of patients are also undergoing second and third repeat CABG for graft occlusion in the years after the original operation. Newer PTCA techniques are not, as yet, fully evaluated. One technique, atherectomy, has been shown to be no more effective, and more expensive, than conventional balloon angioplasty. In the short term intracoronary stents reduce the problems associated with vessel occlusion after PTCA and therefore reduce the need for further intervention. PTCA should not be performed without ready access to cardiothoracic support. There is an increasing trend towards the development of coronary catheterisation units at peripheral sites. This may lead to increasing, inappropriate use of this investigation in suboptimal circumstances.

CONCLUSIONS

Ischaemic heart disease is an important cause of morbidity and mortality and invasive management techniques are developing rapidly; some service expansion is occurring without trial evidence. More research is required to determine the optimum balance of PTCA, CABG, and angiography and population requirements for these procedures. In the meantime, in the absence of firm long term evidence of the superior cost effectiveness of PTCA compared with CABG, the rapid expansion of this procedure should be limited. Patients should be fully informed of the benefits and disadvantages of CABG and PTCA, where either procedure is indicated, to enable them to make fully informed choices.

Directional atherectomy versus balloon angioplasty for coronary ostial and nonostial left anterior descending coronary artery lesions: results from a randomized multicenter trial. The CAVEAT-I investigators. Coronary Angioplasty Versus Excisional Atherectomy Trial

OBJECTIVES

We hypothesized that atherectomy would be superior to balloon angioplasty for ostial and nonostial left anterior descending coronary artery lesions.

BACKGROUND

Balloon angioplasty of ostial coronary artery lesions has been associated with a lower procedural success rate and a higher rate of complications and of restenosis than angioplasty of nonostial stenoses. Directional coronary atherectomy has been proposed as an alternative therapy for ostial lesions.

METHODS

In the Coronary Angioplasty Versus Excisional Atherectomy Trial (CAVEAT-I), 1,012 patients were randomized to undergo either procedure; 563 patients had proximal left anterior descending coronary artery lesions, of which 74 were ostial. We compared balloon angioplasty with directional atherectomy for early and 6-month results for ostial as well as nonostial proximal left anterior descending coronary artery lesions.

RESULTS

Directional atherectomy led to an initially higher gain in minimal lumen diameter for ostial lesions (1.13 vs. 0.56 mm, respectively, p < 0.001) but a higher rate of adjudicated non-Q wave myocardial infarction (24% vs. 13%, respectively, p < 0.001) than balloon angioplasty and no improvement in restenosis rates (48% vs. 46%, respectively). In the nonostial proximal left anterior descending coronary artery lesions, angiographic restenosis was reduced (51% vs. 66%, p = 0.012), but this was also associated with a higher rate of periprocedural myocardial infarction (8% vs. 2%, p = 0.008 by site and 24% vs. 8%, p < 0.001 by adjudication) and no difference in the need for subsequent coronary artery bypass surgery (7.3% vs. 8.4%, respectively) or repeat percutaneous coronary intervention (24% vs. 26%, respectively).

CONCLUSIONS

For ostial left anterior descending coronary artery stenoses, both procedures yielded similar rates of initial success and restenosis, but atherectomy was associated with more non-Q wave myocardial infarction. In this trial the predominant angiographic benefit (increased early gain and less angiographic restenosis) of atherectomy for the left anterior descending coronary artery was in proximal nonostial lesions. However, the tradeoffs for this angiographic advantage were more in-hospital myocardial infarctions and no decrease in clinical restenosis.

Contrast media effects on hemostatic and thrombotic parameters. Possible consequences for practical techniques and prophylactic measures

This paper reviews the basic mechanisms of the thrombohemorrhagic balance and ways in which contrast media (CM) influence these processes. Coagulation and platelet functions are strongly inhibited by ionic CM, but weakly so by nonionic CM, whereas the former are more detrimental to endothelium, and thus thrombogenic in this sense. Some observations indicate a lower rate of thromboembolic events with the ionic CM in percutaneous transluminal coronary angioplasty (PTCA) and coronary artery bypass grafting (CABG), but this purported difference does not effect mortality or frequency of re-PTCA and emergency CABG. Thus, to challenge these events, strong acting antithrombotics, which also, unlike heparin, inactivate fibrin-bound thrombin, are necessary. Aggressive anti-atherogenic prophylaxis may hamper both thrombosis and reocclusion. The ideal antithrombotic in this setting is yet to be found.