Randomized comparison of coronary stenting with balloon angioplasty in selected patients with acute myocardial infarction

Clinical and angiographic results after MULTI-LINK stent implantation and their relation to aggregation of risk factors: two-year follow-up

Results of trials using the ACS MULTI-LINK (ML) stent, one of the new generation stents, were similar to or slightly better than those of trials using the Palmaz-Shatz stent. The purpose of this study was to evaluate relatively long-term (2 years) clinical outcomes of patients with coronary artery disease treated with the ML stent and to determine independent factors correlated with target lesion revascularization and cardiac events. The present study consisted of 82 consecutive patients who had undergone successful coronary ML stent implantation from January 1997 to December 1999. During the follow-up period, cardiac events occurred in 16 (19.5%) patients. All patients underwent follow-up angiography and 12 (14.6%) of the 82 patients underwent target lesion revascularization. Multiple logistic regression analysis showed that aggregation of risk factors (> or = 3 risk factors) (p = 0.0274, odds ratio=5.14) and percent diameter stenosis >20% (p = 0.0395, OR = 4.586) were the significant explanatory factors of target lesion revascularization. In addition, aggregation of risk factors (> or = 3 risk factors) exhibited a tendency to correlate with cardiac events (p = 0.0528) on multiple logistic regression analysis. The results of the present study suggest that target lesion revascularization after coronary ML stent implantation was influenced by aggregation of major coronary risk factors and residual percent diameter stenosis and that long-term clinical outcome is influenced by the aggregation of risk factors.

Does coronary stenting affect microvascular circulation in patients with anterior acute myocardial infarction? Comparison with balloon angioplasty

The impact of coronary stenting on microvascular circulation in the infarct area was compared with that of balloon angioplasty in 94 patients with acute myocardial infarction (AMI) who underwent coronary revascularization within 6h of onset: 49 patients were treated with balloon angioplasty alone, and 45 were treated with coronary stenting. Microvascular circulation after revascularization was assessed by Thrombolysis in Myocardial Infarction (TIMI) flow grade analysis and ST segment analysis. TIMI flow grade was assessed on the final angiographic image after coronary intervention, and the ST segment was assessed on the 12-lead electrocardiogram recordings just before revascularization and on return to the coronary care unit. The distributions of TIMI flow grade and change in sigmaST (5.1 +/- 10.8 vs 5.1 +/- 9.9mm) were similar between the 2 groups. Predischarge left ventricular ejection fraction (54 +/- 14 vs 54 +/- 15%) and in-hospital outcome were also similar between the 2 groups. The data suggest that coronary stenting did not influence microvascular circulation (improvement or detriment) in patients with reperfused AMI.

Clinical outcomes of patients with diabetes mellitus and acute myocardial infarction treated with primary angioplasty or fibrinolysis

OBJECTIVE

To compare the early and late outcomes of primary percutaneous transluminal coronary angioplasty (PTCA) with fibrinolytic treatment among diabetic patients with acute myocardial infarction (AMI).

DESIGN

Retrospective observational study with data obtained from prospective registries.

SETTING

Tertiary cardiovascular institution with 24 hour acute interventional facilities.

PATIENTS

202 consecutive diabetic patients with AMI receiving reperfusion treatment within six hours of symptom onset.

INTERVENTIONS

Fibrinolytic treatment was administered to 99 patients, and 103 patients underwent primary PTCA. Most patients undergoing PTCA received adjunctive stenting (94.2%) and glycoprotein IIb/IIIa inhibition (63.1%).

MAIN OUTCOME MEASURES

Death, non-fatal reinfarction, and target vessel revascularisation at 30 days and one year were assessed.

RESULTS

Baseline characteristics were similar in these two treatment groups except that the proportion of patients with Killip class III or IV was considerably higher in those treated with PTCA (15.5% v 6.1%, p = 0.03) and time to treatment was significantly longer (103.7 v 68.0 minutes, p < 0.001). Among those treated with PTCA, the rates for in-hospital recurrent ischaemia (5.8% v 17.2%, p = 0.011) and target vessel revascularisation at one year (19.4% v 36.4%, p = 0.007) were lower. Death or reinfarction at one year was also reduced among those treated with PTCA (17.5% v 31.3%, p = 0.02), with an adjusted relative risk of 0.29 (95% confidence interval 0.15 to 0.57) compared with fibrinolysis.

CONCLUSION

Among diabetic patients with AMI, primary PTCA was associated with reduced early and late adverse events compared with fibrinolytic treatment.

Influence of diabetes mellitus on outcome in the era of primary stenting for acute myocardial infarction

The purpose of the present study was to examine the influence of diabetes mellitus (DM) on the clinical and angiographic outcomes in 62 diabetic and 152 nondiabetic patients with acute myocardial infarction (AMI) treated with primary coronary stenting within 12 h of the onset of symptoms. The diabetic patients had a greater incidence of hyperlipidemia, prior myocardial infarction (MI) and multivessel disease. There were no statistically significant differences in other variables. Procedural success was similar in the 2 groups. At a mean follow-up of 2.1 +/- 0.6 years, 13% of diabetic and 11% of nondiabetic patients had died (p = 0.70). The percentage of target vessel revascularization (TVR) was 37% of diabetic and 20% of nondiabetic patients (p = 0.003). Rates of major adverse cardiac events (MACE: death, non-fatal MI, TVR) were 50% of diabetic and 32% of nondiabetic patients (p = 0.007). On multivariate analysis, DM was not a predictor of death. Independent predictors of death were age, multivessel disease, TIMI < or = 2 and cardiogenic shock. However, DM and age were independent predictors of MACE. In conclusion, DM is not an independent predictor of death in patients with AMI after stenting, but diabetic patients had a higher incidence of TVR, making DM an independent predictor of MACE.

Six-month angiographic and 12-month clinical follow-up of MultiLink long (25 to 35 mm) stents for long coronary narrowings in patients with angina pectoris

There are limited prospective angiographic data on stent deployment for long coronary lesions. This multicenter prospective study enrolled 120 patients with a single de novo stenosis >20 mm in length, in a native vessel > or =3 mm diameter, suitable for a MultiLink stent 25 to 35 mm in length with additional stent deployment if required. Quantitative angiography before and immediately after stenting and at 6-month follow-up assessed restenosis for the complete lesion and for 5-mm segments of the stented and adjacent nonstented vessel. By 1 year, myocardial infarction had occurred in 3% and target vessel repeat revascularization in 12% of patients. The mean stented length (35.8 +/- 14.6 mm) closely matched mean lesion length (30.1 +/- 13.5 mm). Restenosis to > or =50% diameter loss occurred in 32% of patients, but to > or =70% in only 8%. Of the 147 segments (5 mm in length) with baseline stenosis <25%, only 3 patients (2%) developed restenosis of > or =50%, and only in 1 of these was it > or =70%. Stenting of long narrowings is associated with good clinical outcome and a low rate of severe restenosis. Mildly diseased segments of long lesions covered by a stent rarely became severely narrowed and had negligible influence on the overall restenosis rate. These data support a strategy of full lesion coverage by stent deployment.

Administration of glycoprotein IIb-IIIa inhibitors in patients with ST-segment elevation myocardial infarction

Patients with ST-segment elevation acute myocardial infarction require immediate reperfusion therapy. Reperfusion therapy can be provided by either pharmacologic or mechanical means. Pharmacologic reperfusion therapy consists of administering fibrinolytics, whereas mechanical reperfusion consists of performing percutaneous intervention, usually with stent placement. Each approach has been shown to decrease mortality, but each has disadvantages in establishing flow in the infarct-related artery. Regardless of the approach, during an acute myocardial infarction, activation and externalization of glycoprotein (GP) IIb-IIIa receptors occur on the surface of platelets. The GP IIb-IIIa inhibitors block the binding of fibrinogen to these platelet receptors. These inhibitors have been investigated in combination with both reperfusion strategies. The goal of adding GP IIb-IIIa inhibitor therapy to either reperfusion approach is to obtain better early, complete, and sustained reperfusion. Subsequently, this should lead to better clinical outcomes for patients with ST-segment elevation acute myocardial infarction. Although no mortality benefit has been seen with the addition of GP IIb-IIIa inhibitor therapy, ischemic complications have been reduced significantly.

Rationale for on-site cardiac surgery for primary angioplasty: a time for reappraisal

Since the early 1990s, with significant improvement in the procedural success of percutaneous coronary interventions (PCIs), there has been a concomitant reduction in the need for emergency coronary artery bypass graft surgery. This review article focuses on the need for on-site cardiac surgery in patients with acute myocardial infarction undergoing primary angioplasty at centers without on-site cardiac surgical backup. It gives an overview of the need for emergency bypass surgery in both the large trial setting and the community hospital setting. Special consideration is also given to the risks and benefits of primary angioplasty compared with thrombolytic therapy, transfer to an institution with an on-site cardiac surgical facility compared with primary PCI, the frequency and indications for emergency cardiac surgery related and unrelated to primary angioplasty and the requirements for primary angioplasty that must be met in hospitals without the capability of on-site cardiac surgery.

Interventional therapy of the acute coronary syndromes

The acute coronary syndromes (ACS) have in common rupture of a vulnerable plaque, leading to exposure of the subendothelial surface and plaque core. The resultant thrombosis leads to a variable degree of flow occlusion, the extent of which differentiates the three syndromes and their treatment by percutaneous coronary intervention (PCI). The guiding principle in the decision when to use PCI in the ACS is that the more time critical and high risk the clinical situation, the more likely it is that PCI will improve ultimate outcome. The use of risk stratification by clinical variables can lead to better triage of patients with non-ST-elevation myocardial infarction (MI) and unstable angina between PCI and medical management. Patients presenting with symptoms suggestive of prolonged ischemia should have an electrocardiogram searching for ST changes, a targeted physical, and blood drawn for rapid assay of cardiac enzymes. In the event that ST elevations suggest infarction, while medical therapy is initiated, emergency cardiac catheterization can be organized. PCI in ACS requires adjunctive antiplatelet and antithrombin therapy, and, in general, coronary stenting is advisable. Among patients with non-ST-elevation MI or unstable angina who can be medically stabilized, the presence of high clinical risk scores would favor early coronary angiography. In their absence, medical therapy can be pursued, unless recurrent ischemia occurs. When the patient's condition is stable, evaluation by stress testing can be used to guide further decisions.

Comparison of results of coronary angioplasty for acute myocardial infarction in patients > or =75 years of age versus patients <75 years of age

We reviewed 1,063 consecutive patients treated with direct coronary angioplasty for acute myocardial infarction (AMI): 261 were > or =75 and 802 were <75 years of age. Compared with the younger group, the older group had a higher percentage of women (48% vs 22%, p <0.0001), multivessel coronary disease (50% vs 39%, p <0.01), overall in-hospital mortality (8.4% vs 3.7%, p <0.01), cardiac mortality rate (6.1% vs 3.1%, p <0.05), and noncardiac mortality rate (2.3% vs 0.6%, p <0.05). Successful reperfusion was achieved in both groups at a similarly high rate (93% and 95%, p = NS). Hospital mortality was similar whether reperfusion was successful or failed. Successful compared with unsuccessful angioplasty decreased mortality rates in the older (6.6% vs 33%, p <0.0001) and younger (3.0% vs 18%, p <0.0001) groups. When reperfusion was successful, the cardiac mortality rate in older patients was not significantly higher than in younger patients: 4.1% vs 2.4%, p = NS.

Comparison of angioplasty with stenting, with or without abciximab, in acute myocardial infarction

BACKGROUND

As compared with thrombolytic therapy, primary percutaneous transluminal coronary angioplasty (PTCA) in acute myocardial infarction reduces the rates of death, reinfarction, and stroke, but recurrent ischemia, restenosis, and reocclusion of the infarct-related artery remain problematic. When used in combination with PTCA, coronary stenting and platelet glycoprotein IIb/IIIa inhibitors may further improve outcomes.

METHODS

Using a 2-by-2 factorial design, we randomly assigned 2082 patients with acute myocardial infarction to undergo PTCA alone (518 patients), PTCA plus abciximab therapy (528), stenting alone with the MultiLink stent (512), or stenting plus abciximab therapy (524).

RESULTS

Normal flow was restored in the target vessel in 94.5 to 96.9 percent of patients and did not vary according to the reperfusion strategy. At six months, the primary end point - a composite of death, reinfarction, disabling stroke, and ischemia-driven revascularization of the target vessel - had occurred in 20.0 percent of patients after PTCA, 16.5 percent after PTCA plus abciximab, 11.5 percent after stenting, and 10.2 percent after stenting plus abciximab (P<0.001). There were no significant differences among the groups in the rates of death, stroke, or reinfarction; the difference in the incidence of the primary end point was due entirely to differences in the rates of target-vessel revascularization (ranging from 15.7 percent after PTCA to 5.2 percent after stenting plus abciximab, P<0.001). The rate of angiographically established restenosis was 40.8 percent after PTCA and 22.2 percent after stenting (P<0.001), and the respective rates of reocclusion of the infarcted-related artery were 11.3 percent and 5.7 percent (P=0.01), both independent of abciximab use.

CONCLUSIONS

At experienced centers, stent implantation (with or without abciximab therapy) should be considered the routine reperfusion strategy.

Long-term follow-up after coronary stent implantation in patients with coronary artery disease

Prospective randomized trials of coronary stenting in patients with coronary artery disease have shown a reduced incidence of cardiac events. However, little is known of the late outcome of patients treated with coronary stenting. The purpose of this study was to evaluate the relatively long-term clinical outcomes (3 to 6 years) of patients treated with successful coronary stenting. The long-term clinical outcome was studied in 101 consecutive patients (78 males and 23 females) who had undergone successful coronary stent implantation for coronary artery disease in our hospital from October 1994 to September 1997. During a follow-up period of 48.9+/-9.5 months (range, 6-73 months), cardiac events were documented in 37 patients. The rate of survival free of cardiac events was 67% at 3 years. Multiple logistic regression analysis showed that ACC/AHA lesion type and residual percent diameter stenosis greater than 20% after stenting were the significant explanatory factors of adverse cardiac events. Long-term clinical outcome in patients with coronary artery disease treated with successful coronary stenting was influenced by the ACC/AHA lesion type of stented lesion and residual percent diameter stenosis after stent implantation.

Unrestricted availability of intracoronary stents is associated with decreased abrupt vascular closure rates and improved early clinical outcomes

The purpose of this study was to determine whether the unrestricted availability of intracoronary stents is affecting abrupt vascular closure rates and early clinical outcomes. Intracoronary stents have improved procedural outcome despite their application in more complex lesions, but the impact of unrestricted availability of stents on abrupt closure and early clinical outcomes is unknown. Two cohorts were identified retrospectively from a coronary intervention registry: patients treated between 1988 and 1992 (n = 3,617) when stents were not generally available, and patients treated between 1994 and 1997 (n = 4,518) when stents were freely available. The late cohort patients consisted of more females; it also had greater comorbidity and more complex presentation. However, there was a significant reduction in the abrupt closure rates between the two time periods (7% vs. 4%, P < 0.0001). After adjusting for female gender, thrombus, and lesion angulation, the late cohort remained significantly associated with decreased odds of abrupt closure (odds ratio [OR] = 0.62, 95% upper and lower confidence intervals [CI] = 0.52-0.75, P = 0.0001). The late cohort also had decreased in-hospital mortality (OR = 0.91, CI = 0.86-0.95, P = 0.0002) and major adverse clinical event (OR = 0.93, CI = 0.91-0.96, P = 0.0001). Unrestricted availability of intracoronary stents is associated with reduced abrupt closure rates and improved early clinical outcomes among patients undergoing coronary intervention despite treatment of high-risk patients.

Abciximab improves 6-month clinical outcome after rescue coronary angioplasty

BACKGROUND

Few data are available concerning the effects on clinical outcome and left ventricular function of abciximab administration in patients undergoing rescue percutaneous transluminal coronary angioplasty (PTCA) after failed thrombolysis for acute myocardial infarction. The aim of the study was to investigate such effects.

METHODS

Eighty-nine consecutive patients referred to our laboratory from other hospitals for rescue PTCA within 24 hours from the onset of chest pain were prospectively randomized before the procedure to abciximab treatment (44 patients) or placebo (45 patients). No significant differences in baseline characteristics were observed between the 2 groups. Study end points were the occurrence of major adverse cardiac events (MACE) such as death, reinfarction, congestive heart failure, target lesion revascularization, or recurrent ischemia at 30-day and 6-month follow-up and the occurrence of periprocedural bleeding.

RESULTS

Mean time from symptom onset to reperfusion was 8.5 +/-5.4 hours; rescue PTCA was successful in 96% of patients. The incidence of major, moderate, and minor bleeding was similar in the 2 groups. At 30-day follow-up, the echocardiographic left ventricular wall motion score index showed a significantly higher improvement in the abciximab group versus the placebo group (P <.001). At 6-month follow-up, the incidence of MACE was 11% in the abciximab group versus 38% in the placebo group (P =.004). Abciximab administration (P =.003) and cardiogenic shock (P =.005) were the only independent predictors of the occurrence of MACE at multivariable analysis.

CONCLUSION

Treatment with abciximab during rescue PTCA positively affects clinical outcome at 6-month follow-up without increasing periprocedural bleeding.

Fifteen-year trend in the treatment and outcome of acute myocardial infarction in Japan

To assess the changes in treatment and outcome of acute myocardial infarction (AMI) over a 15-year period, the medical records of 1,437 patients with AMI who underwent emergency coronary angiography within 24h of the onset of chest pain at Hiroshima City Hospital from 1985 to 1999 were reviewed. The patients were divided into 3 groups in chronological order: group 1 (1985-89, n=439), group 2 (1990-94, n=453) and group 3 (1995-99, n=545). Conventional balloon angioplasty and thrombolysis were frequently performed in group 1 (56% and 29%, respectively) and group 2 (71% and 13%, respectively), whereas coronary stenting and conventional balloon angioplasty were more often performed in group 3 (57% and 23%, respectively). The achievement of TIMI grade 3 flow improved in the chronological order (62%, 80% and 85%, respectively; p<0.001). The incidence of reinfarction was lower in group 3 (4.2%) than groups 1 and 2 (8.0% and 7.5%, respectively; p=0.007), and in-hospital mortality decreased from group 1 to group 3 (11.8%, 8.2% and 5.5%, respectively; p=0.002). Stenting is now the most frequently chosen treatment for AMI and sustained TIMI grade 3 flow is obtained in most of the cases, with the result that mortality has reduced by 50% in the past decade.

A randomized comparison of direct stenting with conventional stent implantation in selected patients with acute myocardial infarction

OBJECTIVES

We sought to determine whether direct stenting might prevent the adverse events associated with stent implantation during primary angioplasty and to compare it with conventional stent implantation in patients with acute myocardial infarction (AMI).

BACKGROUND

No trial has demonstrated that stents favorably influence mortality rate. Recent studies have even suggested a negative impact of stents on coronary blood flow and clinical outcome.

METHODS

Of 409 patients treated by primary angioplasty with stent implantation in our center, 206 (50%) were enrolled in this randomized, single-center trial and allocated to direct stent implantation (n = 102) or stent implantation after balloon pre-dilation (n = 104). The study end points included angiographic results (final corrected Thrombolysis In Myocardial Infarction [TIMI] frame count and a composite end point of slow and no-reflow or distal embolization), an electrocardiogram marker of myocardial reperfusion assessment (ST-segment resolution) and in-hospital clinical outcome (death and recurrent infarction).

RESULTS

Direct stent implantation failed in eight patients but succeeded after pre-dilation in all. A non-significant increase in TIMI flow grade 3 was achieved after direct stenting (95.1% vs. 93.3%, p = 0.74) without significant difference in the corrected TIMI frame count (31.5 +/- 17 and 35.2 +/- 20 frames after direct and conventional stent, respectively, p = 0.42). The composite angiographic end point was significantly reduced by direct stent implantation (11.7% vs. 26.9%, p = 0.01). ST-segment resolution was also significantly improved after direct stent (no ST-segment resolution in 20.2% vs. 38.1% after direct and conventional stent, respectively, p = 0.01). Death and/or recurrent infarction occurred in six patients after conventional stent implantation and in two patients after direct stenting (p = 0.28).

CONCLUSIONS

In selected patients with AMI, direct stenting can be applied safely and effectively. This strategy may result in a significant reduction of microvascular injury, as suggested by improved ST-segment resolution after reperfusion with major potential clinical consequences.

Quality of life after balloon angioplasty or stenting for acute myocardial infarction. One-year results from the Stent-PAMI trial

OBJECTIVES

The goal of this study was to compare the impact of primary stenting or percutaneous transluminal coronary angioplasty (PTCA) on health-related quality of life (HRQOL) in patients undergoing direct angioplasty for acute myocardial infarction (AMI).

BACKGROUND

Previous studies have demonstrated that coronary stenting reduces clinical and angiographic restenosis compared with PTCA. However, the impact of stenting on HRQOL from the patient's perspective remains unknown.

METHODS

We administered the Seattle Angina Questionnaire and the Medical Outcomes Study Short-form Survey at 1, 6 and 12 months after initial treatment to all North American patients in the Stent-Primary Angioplasty for Myocardial Infarction trial (Stent-PAMI) (n = 509)-a randomized trial comparing primary stenting to conventional PTCA for patients with AMI.

RESULTS

At one month, most HRQOL measures were similar for the two groups, but stent patients reported less bodily pain than PTCA patients (p = 0.03). At six-month follow-up, stenting resulted in significant improvements in several dimensions of HRQOL including reduced anginal frequency and bodily pain as well as improved disease perception (all p < or = 0.03) and a trend towards better anginal stability (p = 0.056). By 12-month follow-up, however, none of these differences remained statistically significant. These differences in HRQOL were largely explained by the greater need for ischemia-driven target-vessel repeat revascularization procedures in PTCA patients during the first six months (16.0% vs. 6.2%, p < 0.001).

CONCLUSIONS

In patients undergoing revascularization for AMI, initial stent placement is associated with improvements in several dimensions of health status during the first six months of follow-up. In the absence of differences in mortality, these findings add to the overall argument in favor of initial stenting in patients treated with mechanical reperfusion for myocardial infarction.

Defining the role of abciximab for acute coronary syndromes: lessons from CADILLAC, ADMIRAL, GUSTO IV, GUSTO V, and TARGET

Acute coronary syndromes (ACS), including those associated with or without ST-segment elevation, share a common pathophysiology mediated by activated platelets and thrombin. It is becoming increasingly appreciated that reperfusion therapies using primary mechanical or pharmacologic strategies result in suboptimal reperfusion at the myocardial tissue level. Complete reperfusion of the coronary microvasculature has recently been shown to be an important predictor for survival following myocardial infarction. Abciximab has well-established clinical benefits in numerous interventional trials. Through its anti-platelet and anti-thrombotic activities, abciximab reduces thrombus formation and hence minimizes risk of thrombotic microvascular embolization and improves tissue-level reperfusion. Several recent landmark trials have evaluated the clinical efficacy of adjunctive abciximab during mechanical or pharmacologic reperfusion therapy in the setting of ACS. This article provides an update of the role of abciximab in the treatment for ACS based on the results of these clinical trials.

Direct infarct artery stenting without predilation and no-reflow in patients with acute myocardial infarction

BACKGROUND

In patients with acute myocardial infarction (AMI), the rate of microvascular embolization and no-reflow promoted by coronary stenting with the use of conventional techniques (CS) appears to be greater than the one that occurs with balloon angioplasty. The minor invasiveness of direct stenting (DS) of the infarct artery without predilation could be expected to reduce embolization in the coronary microvasculature and no-reflow in patients with AMI.

METHODS

In a cohort of 423 consecutive patients with AMI who underwent infarct-artery stenting, we compared CS and DS in terms of angiographic no-reflow rate and 1-month clinical outcome.

RESULTS

At baseline patients who underwent DS (n = 110) had a better risk profile compared with the use of CS (n = 313). The incidence of angiographic no-reflow was 12% in the CS group and 5.5% in the DS group (P =.040). The 1-month mortality rate was 8% in the CS group and 1% in the DS group (P =.008). The mortality rate was 11% in patients with no-reflow and 5.6% in patients with a normal flow. Multivariate analysis showed that age, preprocedure patent infarct artery, and lesion length were related to the risk of no-reflow. In the subset of patients with a target lesion length </=15 mm, the variables independently related to the risk of no-reflow were age, DS, and final balloon inflation pressure.

CONCLUSIONS

DS in patients with AMI may reduce the incidence of angiographic no-reflow, thereby increasing ultimate effective myocardial reperfusion.

Long-term clinical outcome of rescue balloon angioplasty compared with rescue stenting after failed thrombolysis

Failed thrombolysis following acute myocardial infarction is associated with a poor prognosis. Balloon angioplasty with or without stenting is an established procedure in acute myocardial infarction and for failed thrombolysis (rescue percutaneous transluminal coronary angioplasty [PTCA]). Intracoronary stenting improves initial success rates, decreases incidence of abrupt closure, and reduces the rate of restenosis after angioplasty. The purpose of this study was to compare the effect of rescue PTCA with rescue stenting in the treatment of acute myocardial infarction after failed thrombolysis. Clinical data are from a retrospective review of 102 patients requiring rescue balloon angioplasty or stenting after failed thrombolysis for acute myocardial infarction. There was a greater incidence of recurrent angina in 11 patients (22%) in the rescue PTCA group versus 2 patients (4%) in the rescue stenting group. The in-hospital recurrent myocardial infarction rate was 14% in the rescue PTCA group versus 2% in the stented group. In the rescue PTCA cohort, 11 patients (22%) required in-hospital repeat revascularization versus 2 patients in the stented group. The in-hospital mortality rate was higher in the PTCA group (10%) versus that in the stent group (2%). There was no significant difference in the incidence of postdischarge deaths. Rescue stenting is superior to rescue angioplasty. The procedure is associated with lower in-hospital angina and recurrent myocardial infarction, and the need for fewer repeat revascularizations. Long-term patients treated with stents required fewer revascularization procedures. Overall, rescue stenting was associated with a significantly lower mortality.

Platelet glycoprotein IIb/IIIa inhibition with coronary stenting for acute myocardial infarction

BACKGROUND

When administered in conjunction with primary coronary stenting for the treatment of acute myocardial infarction, a platelet glycoprotein IIb/IIIa inhibitor may provide additional clinical benefit, but data on this combination therapy are limited.

METHODS

We randomly assigned 300 patients with acute myocardial infarction in a double-blind fashion either to abciximab plus stenting (149 patients) or placebo plus stenting (151 patients) before they underwent coronary angiography. Clinical outcomes were evaluated 30 days and 6 months after the procedure. The angiographic patency of the infarct-related vessel and the left ventricular ejection fraction were evaluated at 24 hours and 6 months.

RESULTS

At 30 days, the primary end point--a composite of death, reinfarction, or urgent revascularization of the target vessel--had occurred in 6.0 percent of the patients in the abciximab group, as compared with 14.6 percent of those in the placebo group (P=0.01); at 6 months, the corresponding figures were 7.4 percent and 15.9 percent (P=0.02). The better clinical outcomes in the abciximab group were related to the greater frequency of grade 3 coronary flow (according to the classification of the Thrombolysis in Myocardial Infarction trial) in this group than in the placebo group before the procedure (16.8 percent vs. 5.4 percent, P=0.01), immediately afterward (95.1 percent vs. 86.7 percent, P=0.04), and six months afterward (94.3 percent vs. 82.8 percent, P=0.04). One major bleeding event occurred in the abciximab group (0.7 percent); none occurred in the placebo group.

CONCLUSIONS

As compared with placebo, early administration of abciximab in patients with acute myocardial infarction improves coronary patency before stenting, the success rate of the stenting procedure, the rate of coronary patency at six months, left ventricular function, and clinical outcomes.

Long term outcome and cost-effectiveness of stenting versus balloon angioplasty for acute myocardial infarction

OBJECTIVE

To investigate the long term clinical outcome and cost-effectiveness of stenting compared with balloon angioplasty in patients with acute myocardial infarction.

METHODS

Patients with acute myocardial infarction were randomly allocated to primary stenting (112) or balloon angioplasty (115). The primary end point was the cumulative first event rate of death, non-fatal reinfarction, or target vessel revascularisation. Secondary end points were restenosis at six months and the cost-effectiveness at follow up.

RESULTS

After 24 months, the combined clinical end point of death/reinfarction was 4% after stenting and 11% after balloon angioplasty (p = 0.04). Subsequent target vessel revascularisation was necessary in 15 patients (13%) after stenting and in 39 (34%) after balloon angioplasty (p < 0.001). The cumulative cardiac event-free survival rate was also higher after stenting (84% v 62%, p < 0.001). The angiographic restenosis rate after stenting was less than after balloon angioplasty (12% v 34%, p < 0.001). Despite the higher initial costs of stenting (Dfl 21 484 v Dfl 18 625, p < 0.001), the cumulative costs at 24 months were comparable with those of balloon angioplasty (Dfl 31 423 v Dfl 32 933, p = 0.83).

CONCLUSIONS

Compared with balloon angioplasty, primary stenting for acute myocardial infarction results in a better long term clinical outcome without increased cost.

Primary angioplasty versus intravenous thrombolysis in acute myocardial infarction: can we define subgroups of patients benefiting most from primary angioplasty? Results from the pooled data of the Maximal Individual Therapy in Acute Myocardial Infarction Registry and the Myocardial Infarction Registry

OBJECTIVES

We sought to determine the effectiveness of primary angioplasty compared with thrombolysis in clinical practice.

BACKGROUND

In clinical practice, primary angioplasty for the treatment of acute myocardial infarction (AMI) has not yet been proven more effective than intravenous thrombolysis, nor have subgroups of patients been identified who would perhaps benefit from primary angioplasty.

METHODS

The pooled data of two AMI registries--the Maximal Individual TheRapy in Acute myocardial infarction (MITRA) study and the Myocardial Infarction Registry (MIR)--were analyzed. A total of 9,906 lytic-eligible patients with AMI, with a pre-hospital delay of < or =12 h, were treated with either primary angioplasty (n = 1,327) or thrombolysis (n = 8,579).

RESULTS

Despite differences in the patients' characteristics and concomitant diseases between the two groups, the prevalence of adverse risk factors was balanced. Univariate analysis of hospital mortality showed a more favorable course for patients treated with primary angioplasty: 6.4% versus 11.3% (odds ratio [OR] 0.54, 95% confidence interval [CI] 0.43 to 0.67). This was confirmed by logistic regression analysis (multivariate OR 0.58, 95% CI 0.44 to 0.77). Primary angioplasty was associated with a lower mortality in all subgroups analyzed. We observed a significant correlation between mortality and absolute risk reduction (r = 0.82, p < 0.0001) in the different subgroups: as mortality increased, there was an increase in absolute benefit of primary angioplasty compared with thrombolysis.

CONCLUSIONS

These large registry data showed the effect of primary angioplasty to be more favorable than thrombolysis for the treatment of patients with AMI in clinical practice. This effect was not restricted to special subgroups of patients. As mortality increased, the absolute benefit of primary angioplasty also increased.

Comparative trial of stent-like balloon angioplasty versus coronary stenting for acute myocardial infarction

Primary PTCA has been shown to be superior to any thrombolytic regimen and offers higher reperfusion rates and better coronary flow grades. Its limitations include recurrent ischemia (10%-15%), infarct-related artery reocclusion (5%-10%), angiographic restenosis (35%-50%), and need to perform repeat PTCA or CABG at 6-month follow-up (20%). Thus, the current role of coronary stenting for acute myocardial infarction (AMI) is very promising. From December 1995 through January 1997, 335 patients underwent primary angioplasty during the first 12 hr from symptom onset at our institution. We performed a retrospective study comparing the in-hospital and 6-month follow-up outcome of 61 patients who underwent coronary stenting (stent group) against 61 patients with optimal (residual lesion stenosis < 30%) balloon-only primary angioplasty (stent-like group). Patients were routinely treated with aspirin, and ticlopidine was given only to the stent group. In-hospital major adverse cardiac events (MACE) rate was 11.5% without statistical differences between the groups. Cardiac death rate was similar in both groups (4.9 vs. 6.6%; P = 1.0) and only two (3.3%) patients from the stent group and none from the PTCA group had nonfatal myocardial reinfarction. At 6-month follow-up, the rate of recurrent angina was higher in the stent-like group (30.9 vs. 7.1%; P < 0.001). Multivariate analysis showed that only stenting of the infarct-related artery was a borderline independent predictor for MACE (OR = 0; 95% CI = 0-1; P = 0.057). Primary stenting for AMI reduces the rate of recurrent angina or symptoms and MACE at 6-month follow-up.

Six-month angiographic follow-up after intravascular ultrasound-guided stenting of infarct-related artery: comparison with non-infarct-related artery

BACKGROUND

Compared with balloon angioplasty, stenting has been established as an effective treatment modality to reduce restenosis in patients with acute myocardial infarction. However, the immediate results that predict favorable long-term outcomes in the acute infarct stenting are unknown. Therefore, we evaluated long-term outcomes of stenting for infarct-related artery (IRA) lesions by using intravascular ultrasound (IVUS) compared with that of stenting for non-IRA lesions.

METHODS

IVUS-guided coronary stenting was successfully performed in 510 native coronary lesions (105 IRA vs 405 non-IRA). A 6-month follow-up angiogram was performed in 419 (82.2%) lesions: 87 (82.9%) IRA lesions and 332 (82.0%) non-IRA lesions. Coronary stenting on the IRA lesions was successfully performed within 7 to 10 days after onset of infarction in 42 patients and within 12 hours in 45 patients. Results were evaluated by clinical, angiographic, and IVUS methods.

RESULTS

There were no significant differences in clinical and angiographic variables between the two groups. IVUS variables including reference vessel area and minimal stent area were also similar between the two groups. There was no significant difference in angiographic restenosis rate between the two groups in cases of minimal stent area > or = 7 mm(2): 12.8% (6 of 47) in IRA versus 19.1% (33 of 173) in non-IRA lesions (P = .315). However, the angiographic restenosis rate in cases of minimal stent area <7 mm(2) was 50% (20 of 40) in IRA lesions versus 31.5% (50 of 159) in non-IRA lesions (P = .028).

CONCLUSIONS

Angiographic restenosis is significantly higher in stenting for IRA lesions compared with that for non-IRA lesions in cases of minimal stent area < 7 mm(2).

REPERFUSION THERAPY FOR ACUTE MYOCARDIAL INFARCTION

A mechanical approach to reperfusion using direct coronary angioplasty is now an established and effective treatment for acute myocardial infarction, but it is not immediately available at most community hospitals. This article will outline the indications for use of reperfusion therapy on patients with AMI, discuss all currently available treatment options, and examine the potential role of combined pharmacologic and mechanical therapy for reperfusion in AMI.

New developments in percutaneous coronary intervention

The field of percutaneous coronary intervention continues to progress at a tremendous rate. Advances in techniques, in device technology, and in adjunctive therapy have increased significantly the number of patients who may benefit from angioplasty and have increased the early and long-term success rates of these procedures. Future progress in radiation therapy, IIb/IIIa inhibitors, stent design, and other novel approaches undoubtedly will offer further improvements in the capability of coronary interventions to help patients live longer and feel better.

Combined revascularization strategy for acute myocardial infarction in patients with intracoronary thrombus: preceding intracoronary thrombolysis and subsequent mechanical angioplasty

Thrombus in the infarct-related artery is one of the limitations for flow restoration in primary percutaneous transluminal coronary angioplasty (PTCA) treatment for acute myocardial infarction (AMI). The present study investigated the benefit of preceding intracoronary thrombolysis (ICT) by retrospectively analyzing acute phase flow restoration in 80 AMI patients with intracoronary thrombus: 40 undergoing primary PTCA alone (primary PTCA group) and 40 treated with preceding ICT plus PTCA (combined group). Acute phase Thrombolysis in Myocardial Infarction (TIMI) grade flow was as follows: TIMI 0/1: 35.0% vs 12.5% for the primary PTCA group and the combined group, p=0.06; TIMI 2: 7.5% vs 15.0%, p=NS; TIMI 3: 57.5% vs 72.5%, p=NS). In the subgroup analysis, it was also less in the combined group among 33 patients with a left anterior descending coronary artery (LAD) lesion (42.1 % vs 7.1%, p=0.08), but not among the remaining 47 with either a right coronary artery or left circumflex artery lesion. The combined therapy may potentially provide better acute phase flow restoration in AMI patients with an intracoronary thrombus in a LAD lesion.

Stenting versus thrombolysis in acute myocardial infarction trial (STAT)

OBJECTIVES

We sought to directly compare primary stenting with accelerated tissue plasminogen activator (t-PA) in patients presenting with acute ST-elevation myocardial infarction (AMI).

BACKGROUND

Thrombolysis remains the standard therapy for AMI. However, at some institutions primary angioplasty is favored. Randomized trials have shown that primary angioplasty is equal or superior to thrombolysis, while recent studies demonstrate that stent implantation improves the results of primary angioplasty.

METHODS

Patients presenting with AMI were randomly assigned to primary stenting (n = 62) or accelerated t-PA (n = 61). The primary end point was the composite of death, reinfarction, stroke or repeat target vessel revascularization (TVR) for ischemia at six months.

RESULTS

The primary end point was significantly reduced in the stent group compared with the accelerated t-PA group, 24.2% versus 55.7% (p < 0.001). The event rates for other outcomes in the stent group versus the t-PA group were as follows: mortality: 4.8% versus 3.3% (p = 1.00); reinfarction: 6.5% versus 16.4% (p = 0.096); stroke: 1.6% versus 4.9% (p = 0.36); recurrent unstable ischemia: 9.7% versus 26.2% (p = 0.03) and repeat TVR for ischemia: 14.5% versus 49.2% (p < 0.001). The median length of the initial hospitalization was four days in the stent group and seven days in the t-PA group (p < 0.001).

CONCLUSIONS

Compared with accelerated t-PA, primary stenting reduces death, reinfarction, stroke or repeat TVR for ischemia. In centers where facilities and experienced interventionists are available, primary stenting offers an attractive alternative to thrombolysis.

Efficacy of heparin-coated stent in early setting of acute myocardial infarction

Primary stenting has been reported to be superior to balloon percutaneous transluminal coronary angioplasty (PTCA) in acute myocardial infarction (AMI) for recurrent ischemia, target lesion revascularization, and restenosis. However, concerns about early reocclusion or thrombosis after stenting in the very thrombotic environment of acute myocardial infarction still remain. Therefore, postprocedural short-term heparin or GpII(b)/III(a) receptor blockades has been used. The aim of our study was to evaluate the safety, feasibility, and long-term efficacy of heparin-coated stent in the early setting of AMI without postprocedural heparin or GpII(b)/III(a) receptor blockade infusion. We studied 102 consecutive patients presenting to cardiac catheterization laboratory < or = 6 hr from the onset of chest pain. No patients who were implanted with heparin-coated stents received heparin or GpII(b)/III(a) receptor blockade infusion after the procedures, not even patients who showed an angiographically large thrombus burden before stenting. Patients were evaluated for clinical endpoints at 30 days and 6 months. Coronary angiography was required for all patients at 2 weeks and 6 months after the procedure. Angiographic and procedural successes were 100% and 98%, respectively. Two patients (2%) died of heart failure without evidence of reocclusion of stented vessel during the hospitalization and 4 (4%) additional patients died of refractory heart failure within the first 6 months. Major bleeding complication occurred in one patient (1%). Recurrent myocardial infarction developed in one patient at 4 months. Early angiographic follow up at 2 weeks was performed in 88% of all patients, none of whom showed thrombotic stent occlusion. Six-month angiographic follow-up was completed in 71%(64/91) of eligible patients and binary restenosis was present in 17.2% of stented vessels. Eight(8%) patients underwent repeat PTCA. Cardiac event-free survival rate at 6 months was 86.3%. This study demonstrates that heparin-coated stents are safe in the early setting of acute myocardial infarction and no additional heparin infusion after stenting is necessary, which may reduce bleeding complications. Angiographic restenosis rate compares favorably to the binary restenosis rate from other studies with uncoated stents.

Cardiologic problems in the post acute ventilated patient

Chronically critically ill patients who develop acute respiratory failure commonly have complicating cardiac pathology that may or may not be evident at initial evaluation. The acute coronary syndromes should be excluded in all patients presenting with respiratory failure. Cardiac rhythm disturbances are common and should be actively investigated and treated in all critically ill patients. Heart failure is common in the chronically critically ill patient but usually responds to early diagnosis and prompt treatment. Finally, cardiogenic shock carries a poor prognosis in most patient subsets except when it is caused by cardiac tamponade. The intensivist must be vigilant for cardiac pathology complicating the recovery of patients with acute respiratory illness and initiate the search for correctable problems that may precipitate further episodes of respiratory insufficiency.

Early and mid-term angiographic and clinical results after intracoronary duet stent placement

The Duet stent (Guidant/Advanced Cardiovascular Systems) is a new stent with a corrugated ring design and very limited data on its short- and mid-term performance. Accordingly, in this study we sought to determine the early and mid-term clinical and angiographic outcomes in a moderate-sized series of 86 consecutive patients who underwent placement of 108 premounted Duet stents in 98 coronary lesions. Procedural success, accomplished in all patients, was accompanied by a significant reduction in lesion severity from 89% +/- 11% before to 5% +/- 3% diameter stenosis after the procedure (P = 0.0001) and a 0.9% incidence of subacute stent thrombosis. Angiographic restudy at 5.7 months in 89% of eligible patients revealed a binary in-stent restenosis rate of 26%. Coronary stenting with the new Duet stent confers a low risk of stent thrombosis and a favorable mid-term clinical and angiographic outcome despite the presence of a large proportion of patients at high risk of in-stent restenosis.

Coronary stenting and platelet glycoprotein IIb/IIIa receptor blockade in acute myocardial infarction

BACKGROUND

Myocardial reperfusion in patients with acute myocardial infarction may be successfully achieved with primary angioplasty. However, angioplasty, as a primary reperfusion strategy, has limitations such as early recurrent ischemia and late restenosis and reocclusion. To improve the short- and long-term results of primary angioplasty, the use of adjunct strategies has been proposed.

METHODS

We reviewed published studies on the effectiveness of primary angioplasty, stenting, and platelet glycoprotein IIb/IIIa receptor blockade and identified the advantages and disadvantages of these interventions in patients with acute myocardial infarction.

RESULTS

Recent findings suggest that patients may benefit from stenting of the infarct artery and from the use of more potent antiplatelet agents such as platelet glycoprotein IIb/IIIa receptor inhibitors. In randomized trials that compared primary angioplasty versus primary stenting, stent implantation was associated with a lower rate of death, reinfarction, and especially target vessel revascularization. Platelet glycoprotein IIb/IIIa receptor inhibitors prevented acute ischemic complications after primary angioplasty and primary stenting. In addition to maintaining large vessel patency, these drugs may protect the microvasculature after primary stenting, allowing better functional recovery of the risk area.

CONCLUSIONS

Coronary artery stenting in acute myocardial infarction reduces the rate of restenosis and the incidence of problems related to recurrent ischemia. Platelet glycoprotein IIb/IIIa receptor inhibitors may come to play a key role in association with mechanical reperfusion. However, the cost-effectiveness and long-term clinical outcome of this combined pharmacologic/mechanical intervention require further study before this strategy can be recommended for routine use.

Final results of a randomized trial comparing the MULTI-LINK stent with the Palmaz-Schatz stent for narrowings in native coronary arteries

The MULTI-LINK (ML) stent is a novel second generation coronary stent. The ACS MultiLink Stent Clinical Equivalence in De Novo Lesions Trial (ASCENT) randomized 1,040 patients with single, de novo native vessel lesions to treatment with the ML stent or the benchmark Palmaz-Schatz (PS) stent, to demonstrate that the ML stent was not inferior to (i.e., equivalent or better than) the PS stent in terms of target vessel failure by 9 months. Successful stent delivery was achieved in 98.8% versus 96.9% of patients, with a slightly lower postprocedural diameter stenosis (8% vs 10%, p = 0.04), and no difference in 30-day major adverse cardiac events (5.0% vs 6.5%) for the ML stent versus the PS stent. The primary end point of target vessel failure at 9 months was seen in 15.1% of ML-treated patients versus 16.7% of PS-treated patients, with the ML proving to be equal or superior to the PS stent (p <0.001 by test for equivalency). In a prespecified subset, angiographic restudy showed a nonsignificant trend for reduced ML restenosis (16.0% vs 22.1%). Thus, the ML stent showed excellent deliverability and acute results, with 9-month clinical and 6-month angiographic outcomes that were equivalent or better than the PS stent.

Final results of a randomized trial comparing the NIR stent to the Palmaz-Schatz stent for narrowings in native coronary arteries

The NIR stent is a novel second generation tubular stent that was designed to overcome some of the limitations of the earlier Palmaz-Schatz (PS) stent design. The NIR Vascular Advanced North American (NIRVANA) trial randomized 849 patients with single coronary lesions to treatment with the NIR stent or the PS stent. The study was an "equivalency" trial, designed to demonstrate that the NIR stent was not inferior to (i.e., equivalent or better than) the PS stent, for the primary end point of target vessel failure (defined as death, myocardial infarction, or target vessel revascularization) by 9 months. Successful stent delivery was achieved in 100% versus 98.8%, respectively, with a slightly lower postprocedural diameter stenosis (7% vs. 9%, p = 0.04) after NIR and PS stent placement, respectively. Major adverse cardiac events (death, myocardial infarction, repeat target lesion revascularization) were not different at 30 days (4.3% vs. 4.4%). The primary end point of target vessel failure at 9 months was seen in 16.0% of NIR versus 17.2% of PS patients, with the NIR proving to be equal or superior to the PS stent (p <0.001 by test for equivalency). Angiographic restudy in 71% of a prespecified cohort showed no significant difference in restenosis (19.3% vs 22.4%). Thus, the NIR stent showed excellent deliverability with slightly better acute angiographic results and equivalent or better 9-month target vessel failure rate when compared with the PS stent.

Management of acute coronary syndromes in the community hospital without cardiac surgical capability: how can access to interventional therapy be improved?

Early coronary artery intervention is emerging as the treatment of choice for patients with high risk acute coronary syndromes (ACS). However, most patients with ACS are admitted to hospitals which do not have ready access to interventional therapy. Extending the benefits of early intervention to this population is problematic at such community hospitals, since this approach would require either emergency transfer to a tertiary center or the performance of angioplasty on-site at hospitals without cardiac surgical capability. A third solution, pre-hospital ambulance triage to interventional centers, is not currently practised in most countries. A growing body of evidence indicates that hospitals without cardiac surgical capability can establish safe and effective primary angioplasty programs. Patients with acute myocardial infarction (AMI) who are randomized to transfer for primary angioplasty without fibrinolytic treatment have fewer major adverse cardiac events than those treated with fibrinolytics alone or fibrinolytics and transfer. In patients with unstable angina (UA) or non-ST-elevation AMI, an early aggressive approach led to a significant reduction in the composite end-point of death, AMI, or rehospitalization for recurrent UA at 6 months with no increase in cost, compared with conservative management. Ongoing trials in Europe indicate that pre-hospital ambulance triage of patients with large AMI to interventional centers can be remarkably rapid, safe, and effective. In order to improve the access of such patients to early intervention, 3 interdependent solutions are proposed:The development of more interventional programs at those hospitals without cardiac surgical facilities that can meet rigorous standards. The development of protocols to insure the early and more frequent transfer of patients with high-risk ACS to interventional centers for coronary angiography and revascularization. The pre-hospital triage of patients with AMI to established heart attack centers with 24-hour, 365-day emergency interventional capability for immediate primary angioplasty (after the model of trauma centers). Universal triage/transfer of all such patients to interventional centers could, however, quickly flood the capability of all tertiary surgical hospitals. With the aging of the 'baby boomers' in the near future, the need for interventional facilities will increase even further. Thus the second and third solutions above will ultimately depend on the first solution. Improving the delivery of interventional therapy to patients with ACS can provide a substantial healthcare benefit to society.

Long-term follow-up of a randomized study of primary stenting versus angioplasty in acute myocardial infarction

PURPOSE

Primary stenting leads to better short-term outcomes than does balloon angioplasty among patients with acute myocardial infarction, but there are no data available on long-term follow-up.

SUBJECTS AND METHODS

We designed a randomized study with long-term follow-up to compare primary angioplasty with angioplasty accompanied by implantation of a silicon carbide-coated stent in patients within 24 hours after the onset of acute myocardial infarction. All 88 patients had lesions that were suitable for coronary stenting.

RESULTS

There were 44 patients in each of the randomization groups. During long-term follow-up (mean +/- SD: 710+/-282 days), primary stenting was associated with a reduction in the combined endpoint of death, reinfarction, or target vessel revascularization (10 [23%] versus 19 [43%], P = 0.03); death (4 [9%] versus 8 [18%], P = 0.18); reinfarction (1 [2%] versus 4 [9%], P = 0.18); and target lesion revascularization (7 [16%] versus 15 [34%], P = 0.04). Rehospitalization due to ischemic events (unstable angina or reinfarction) was also less frequent in the stent group (6 [14%] versus 10 [23%], P = 0.20).

CONCLUSION

Primary stenting in acute myocardial infarction is significantly superior to angioplasty alone in both short-term and long-term follow-up.

Decreasing hospital mortality between 1994 and 1998 in patients with acute myocardial infarction treated with primary angioplasty but not in patients treated with intravenous thrombolysis. Results from the pooled data of the Maximal Individual Therapy in Acute Myocardial Infarction (MITRA) Registry and the Myocardial Infarction Registry (MIR)

OBJECTIVES

We investigated changes in the clinical outcome of primary angioplasty and thrombolysis for the treatment of acute myocardial infarction (AMI) from 1994 to 1998.

BACKGROUND

Primary angioplasty for the treatment of AMI is a sophisticated technical procedure that requires experienced personnel and optimized hospital logistics. Growing experience with primary angioplasty in clinical routine and new adjunctive therapies may have improved the outcome over the years.

METHODS

The pooled data of two German AMI registries: the Maximal Individual Therapy in AMI (MITRA) study and the Myocardial Infarction Registry (MIR) were analyzed.

RESULTS

Of 10,118 lytic eligible patients with AMI, 1,385 (13.7%) were treated with primary angioplasty, and 8,733 (86.3%) received intravenous thrombolysis. Patients characteristics were quite balanced between the two treatment groups, but there was a higher proportion of patients with a prehospital delay of >6 h in those treated with primary angioplasty. The proportion of an in-hospital delay of more than 90 min significantly decreased in patients treated with primary angioplasty over the years (p for trend = 0.015, multivariate odds ratio [OR] for each year of the observation period = 0.84, 95% confidence interval [CI]: 0.73-0.96) but did not change significantly in patients treated with thrombolysis. Hospital mortality decreased significantly in the primary angioplasty group (p = 0.003 for trend; multivariate OR for each year = 0.73, 95% CI: 0.58-0.93). However, for patients treated with thrombolysis, hospital mortality did not change significantly (p for trend 0.175, multivariate OR for each year: 1.02, 95% CI: 0.94- 1.11).

CONCLUSIONS

Compared with thrombolysis the clinical results of primary angioplasty for the treatment of AMI improved from 1994 to 1998. This indicates a beneficial effect of the growing experience and optimized hospital logistics of this technique over the years.

Comparison of in-hospital outcomes after coronary angioplasty with or without stent placement for acute myocardial infarction

This study compared the in-hospital outcomes of patients treated with or without stent placement during mechanical revascularization for acute myocardial infarction. After correction for differences in baseline characteristics, patients treated with stent placement had lower in-hospital mortality.

Primary stenting in nonselected patients with acute myocardial infarction: the Multilink Duet in Acute Myocardial Infarction (MIAMI) trial

Most randomized trials comparing primary stenting with primary coronary angioplasty (PTCA) excluded patients at high risk from enrollment, thus arising the important question about the generalizability of the randomized trial results to all patients with AMI. The aim of this study was to assess the feasibility and effectiveness of a primary infarct-related artery (IRA) stenting strategy using a second-generation tubular stent in nonselected patients with acute myocardial infarction (AMI). All patients with AMI were considered eligible for primary IRA stenting. No restriction was made based on age or clinical status on presentation, or coronary anatomy, except in cases of a reference IRA diameter < 2.5 mm. The primary endpoint of the study was clinical target vessel failure defined as death, reinfarction, or repeat TVR due to restenosis or reocclusion of the IRA. Between June 1998 and March 1999, 201 consecutive patients with AMI underwent mechanical recanalization of the IRA. The mean age was 64 +/- 12, and 16% of patients were aged 75 years or over. The incidence of shock was 9%. Primary IRA stenting was performed in 89% of the patients. Patients who underwent PTCA alone had a smaller IRA diameter as compared to patients with a stented IRA (2.48 +/- 0.46 mm vs. 3.15 +/- 0.37 mm; P < 0.001). There were no stent deployment failures. The 6-month primary endpoint rate was 15% (2 deaths, 27 repeat TVR, 0 reinfarctions), while the 6-month angiographic restenosis rate was 22%. Primary IRA stenting in nonselected patients with AMI is highly feasible and associated with favorable clinical and angiographic outcomes. Cathet. Cardiovasc. Intervent. 51:273-279, 2000.

Does primary stenting preserve cardiac function in myocardial infarction? A case-control study. NORTH-981 investigators. Network of revascularisation therapy in Hokkaido

OBJECTIVE

To investigate whether coronary stenting limits myocardial injury and preserves left ventricular function.

DESIGN AND SETTING

Prospective multicentre case-control study of primary percutaneous transluminal coronary angioplasty (PTCA) with and without stenting, performed in seven cardiovascular centres.

SUBJECTS AND METHODS

45 consecutive patients with acute myocardial infarction who were treated with successful primary stenting (Stent group) and did not have restenosis were paired with 45 matched control subjects with acute myocardial infarction treated by successful primary PTCA without stenting, also with no restenosis (POBA group).

RESULTS

In comparison with the POBA group, the Stent group-especially those patients with a left anterior descending coronary artery lesion-had a smaller hypokinesis area (mean (SD): 15. 1 (20.0) v 34.4 (24.3) chords), reduced hypokinesis area/risk area (25.2 (31.9)% v 58.8 (40.1)%), and a larger ejection fraction (63.3 (10.2)% v 51.7 (11.7)%) evaluated by quantitative left ventriculography using the centerline method. In the Stent group, the correlation between risk area and hypokinesis area was significantly shifted downward. Multiple logistic regression analysis on infarct size limitation (hypokinesis area/risk area < 50%) identified preinfarction angina in all subjects and preinfarction angina and stenting in patients with left anterior descending coronary artery lesions as explanatory factors.

CONCLUSIONS

Primary PTCA using a coronary stent is effective in preventing myocardial injury and restoring left ventricular function in patients with anterior acute myocardial infarction.