Comparison of coronary stenting versus conventional balloon angioplasty on five-year mortality in patients with acute myocardial infarction undergoing primary percutaneous coronary intervention

Little is known about the influence of stenting versus balloon angioplasty on long-term outcomes (particularly mortality) after primary percutaneous coronary intervention (PCI). We evaluated 2,087 patients with ST-elevation myocardial infarction enrolled in various Primary Angioplasty in Myocardial Infarction (PAMI) trials in the United States, who underwent primary PCI. The main outcome was all-cause mortality at 5 years, obtained through the National Death Index. Of the 2,087 patients, stenting was performed in 692 (33%). The absolute difference in the hospital (2.2% vs 3.3%), 1-year (3.3% vs 5.2%), and 5-year (10% vs 13%) mortality rates favored patients receiving a stent versus conventional balloon therapy, with the difference increasing with time. A multivariate Cox model identified stent use (vs balloon alone) as an independent correlate of lower 5-year mortality (hazard ratio 0.60, 95% confidence interval 0.42 to 0.85). The absolute reduction in mortality was greatest in the highest risk group. In conclusion, compared with balloon angioplasty, stenting during primary PCI not only resulted in better angiographic and short-term outcomes, but also in a sustained beneficial effect on mortality at 5 years. These data support the routine use of coronary stenting in most patients undergoing primary PCI, when feasible.     

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.     

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.     

Comparison of outcomes of diabetic and nondiabetic patients undergoing primary angioplasty for acute myocardial infarction

We sought to determine whether diabetes mellitus independently conferred poor prognosis in patients with acute myocardial infarction (AMI) undergoing primary percutaneous coronary intervention (PCI). In 3,742 patients enrolled in the Primary Angioplasty in Myocardial Infarction (PAMI) studies with the intention of undergoing primary PCI, we compared in-hospital mortality, 6-month mortality, and 6-month major adverse cardiovascular events (MACEs), i.e., composite of death, reinfarction, or ischemic target vessel revascularization (TVR), between diabetics (n = 626, 17%) and nondiabetics (n = 3,116, 83%). We evaluated the independent impact of diabetes on outcomes after adjustment for baseline clinical and angiographic differences. Diabetics had worse baseline clinical characteristics, longer pain onset-to-hospital arrival time, and longer door-to-balloon time. They had more multivessel coronary disease and lower left ventricular ejection fractions, but better baseline Thrombolysis In Myocardial Infarction (TIMI) flow. Diabetics underwent primary PCI less often (88% vs 91%, p = 0.01). During the index hospitalization, diabetics were more likely to die (4.6% vs 2.6%, p = 0.005). During 6-month follow-up, diabetics had higher incidences of death (8.1% vs 4.2%, p <0.0001) and MACEs (18% vs 14%, p = 0.036). In multivariate analysis, diabetes was independently associated with 6-month mortality (hazard ratio 1.53, 95% confidence interval 1.03 to 2.26, p = 0.03), but not with in-hospital mortality or 6-month MACEs. We conclude that diabetics with AMI have less favorable baseline characteristics and are less likely to undergo primary PCI than nondiabetics. Despite excellent angiographic results, diabetics had significantly worse 6-month mortality.     

Long-term outcome after primary stenting versus balloon angioplasty for acute myocardial infarction

The objective of the present prospective multicenter case-control study was to investigate the long-term clinical outcome (5 years) of primary stenting compared to primary percutaneous transluminal coronary angioplasty (PTCA) without stenting (POBA) in patients with acute myocardial infarction at 7 cardiovascular centers in Hokkaido, Japan. Forty-one patients with acute myocardial infarction treated with successful primary stenting (stent group: case) and paired with 41 matched control subjects with acute myocardial infarction treated by successful primary PTCA without stenting (POBA group: control) were analyzed. After 1 year, the stent group had a lower incidence of the combined clinical endpoint (death, rehospitalization due to congestive heart failure, nonfatal myocardial infarction, repeat angioplasty, CABG, or cerebrovascular events) compared to the POBA group (17.1% versus 39.0%, P = 0.049). After 5 years, the incidences of congestive heart failure and cardiac death were the same in both groups. However, compared to the POBA group, the stent group had a lower combined clinical endpoint (34.1% versus 61.0%, P = 0.027). The Kaplan-Meier event-free survival curves of the stent group showed a significantly lower occurrence of clinical events compared to the POBA group (P = 0.0116). Multiple logistic regression analysis of clinical events identified age > or = 69 years (P = 0.0092, odds ratio = 4.179) and stenting (P = 0.0158, odds ratio = 0.279) as explanatory factors. Compared with POBA, primary stenting for acute myocardial infarction results in a better long-term clinical outcome.     

A comparison of systematic stenting and conventional balloon angioplasty during primary percutaneous transluminal coronary angioplasty for acute myocardial infarction

OBJECTIVES

In a multicenter, randomized trial, systematic stenting using the Wiktor stent was compared to conventional balloon angioplasty with provisional stenting for the treatment of acute myocardial infarction (AMI).

BACKGROUND

Primary angioplasty in AMI is limited by in-hospital recurrent ischemia and a high restenosis rate.

METHODS

A total of 211 patients with AMI <12 h from symptom onset, with an occluded native coronary artery, were randomly assigned to systematic stenting (n = 101) or balloon angioplasty (n = 110). The primary end point was the binary six-month restenosis rate determined by core laboratory quantitative angiographic analysis.

RESULTS

Angiographic success (Thrombolysis in Myocardial Infarction [TIMI] flow grade 3 and residual diameter stenosis <50%) was achieved in 86% of the patients in the stent group and in 82.7% of those in the balloon angioplasty group (p = 0.5). Compared with the 3% cross-over in the stent group, cross-over to stenting was required in 36.4% of patients in the balloon angioplasty group (p = 0.0001). Six-month binary restenosis (≥50% residual stenosis) rates were 25.3% in the stent group and 39.6% in the balloon angioplasty group (p = 0.04). At six months, the event-free survival rates were 81.2% in the stent group and 72.7% in the balloon angioplasty group (p = 0.14), and the repeat revascularization rates were 16.8% and 26.4%, respectively (p = 0.1). At one year, the event-free survival rates were 80.2% in the stent group and 71.8% in the balloon angioplasty group (p = 0.16), and the repeat revascularization rates were 17.8% and 28.2%, respectively (p = 0.1).

CONCLUSIONS

In the setting of primary angioplasty for AMI, as compared with a strategy of conventional balloon angioplasty, systematic stenting using the Wiktor stent results in lower rates of angiographic restenosis.     

Comparison of outcomes of direct stenting versus stenting after balloon predilation in patients with acute myocardial infarction (DIRAMI)

Due to recent advances in stent design, stenting without balloon predilation (direct stenting) has become more extensively used in patients with acute myocardial infarction (AMI). We performed a randomized study with broad inclusion criteria and early randomization after presentation to compare direct stenting with stenting after balloon predilation in patients with AMI. A total of 248 patients was randomized. After exclusion of patients not suitable for stenting, the final study group comprised 217 patients. Direct stenting strategy was feasible in 88% of patients with no meaningful complications. Final Thrombolysis In Myocardial Infarction grade 3 flow (96% vs 94%), final Thrombolysis In Myocardial Infarction myocardial perfusion grade 2 or 3 (68% vs 61%), and average ST-segment resolution after the procedure (49% vs 51%) were similar in the direct stenting and predilation groups, respectively (p = NS). Rate of in-stent restenosis was higher in the direct stenting group (30% vs 16%, p = 0.024), which was due to a worse angiographic result after the procedure. At 5 years, a composite of cardiac death, reinfarction, and target lesion revascularization had occurred in 39% in the direct stenting group and 34% in the predilated group (p = 0.40). In conclusion, although at 5 years clinical outcome did not differ significantly between groups, direct stenting was associated with a higher incidence of in-stent restenosis at 1 year. Direct stenting did not improve epicardial and myocardial reperfusion indexes. Direct stenting strategy should not be recommended in all patients with AMI as an alternative strategy to stenting after predilation.     

Sequential vs. kissing balloon angioplasty for stenting of bifurcation coronary lesions.

Coronary angioplasty of bifurcation lesions remains a technical challenge and is believed to result in low procedural success associated with the risk of side-branch occlusion. Furthermore, long-term results are associated with a high rate of reintervention. The aim of the study was to evaluate the immediate and long-term clinical and angiographic results of sequential vs. simultaneous balloon angioplasty (kissing balloon technique) for stenting of bifurcation coronary lesions. Between December 1999 and January 2001, 59 patients underwent coronary angioplasty because of symptomatic bifurcation lesions type III (i.e., side branch originates from within the target lesion of the main vessel, and both main and side branch are angiographically narrowed more than 50%). Twenty-six patients were treated with simultaneous and 33 patients with sequential balloon angioplasty. Main-vessel stent placement was mandatory; side-branch stenting and platelet IIb/IIIa antagonists were allowed at the discretion of the operator. Kissing balloon technique offered no advantage in terms of procedural success or need for repeat target vessel revascularization due to restenosis at 6-month follow-up. Using sequential balloon angioplasty, permanent or transient side-branch compromise rate (TIMI flow < 3) was significantly higher than after kissing balloon technique (33% vs. 0%, respectively; P = 0.003). Major clinical events in-hospital or at 6-month follow-up, however, showed no significant differences. Kissing balloon angioplasty reduces the rate of transient side-branch occlusion compared to sequential PTCA but does not improve immediate or long-term outcome compared to sequential PTCA for stenting of bifurcation lesions.     

Management and outcomes of patients transferred for rescue coronary angioplasty in acute myocardial infarction.

BACKGROUND: Rescue coronary angioplasty (PTCA), though recommended by the guidelines, is not regularly performed after failed lysis in patients with ST-elevation acute myocardial infarction (AMI), and data from large contemporary studies are not available. The outcomes of a recent series of consecutive patients in our Center are presented. METHODS: Between August 2000 and November 2003, 270 patients with AMI < 12 hours were referred to our cath lab for emergency PTCA: 117 (43%) for rescue PTCA after failed lysis, and 153 for primary or facilitated PTCA. The baseline, procedural and outcome data of all patients were prospectively collected, analyzed on an "intention-to-treat" basis and compared. Cineangiographic data were reviewed by three angiographers who were unaware of the clinical data. RESULTS: No significant differences were found between rescue PTCA and primary/facilitated PTCA patients as to: age, female gender, diabetes, hypertension, previous AMI, time from pain onset to the first emergency room admission, heart rate at admission, systolic blood pressure, number of leads with ST-segment elevation, total ST-segment deviation, collateral flow to the infarct-related artery, initial TIMI 2-3 flow, and three-vessel disease. Patients with rescue PTCA, as compared to primary/facilitated PTCA, had a longer time from pain onset to the cath lab (336 +/- 196 vs 229 +/- 155 min, p = 0.0001) and more frequently had an anterior AMI (52 vs 38%, p = 0.027), a higher Killip class (1.5 +/- 0.98 vs 1.26 +/- 0.7, p = 0.02), shock (11 vs 5%, p = 0.073), and intra-aortic balloon pump use (17 vs 8%, p = 0.048); fewer patients were in Killip class 1 (74 vs 85%, p = 0.043). PTCA was performed immediately in 78 vs 95% of patients (p = 0.0001); 8 vs 3 patients had PTCA of the infarct-related artery and 8 vs 1 had bypass surgery later during hospitalization. Patients with rescue PTCA, as compared to primary/facilitated PTCA, had a final TIMI 3 flow in 62 vs 76% of cases (p = 0.017), > or = 70% ST-segment resolution in 36 vs 50% (p = 0.086), and both of the latter in 24 vs 45% (p = 0.006); the overall hospital mortality was 12 vs 6.5%, and 5.8 vs 3.4% when patients in shock on admission were not considered; reinfarction and stroke occurred in 0.9 vs 1.3% and in 2.6 vs 0% of the patients respectively. CONCLUSIONS: Due to referral, rescue PTCA patients were admitted to the cath lab later after the onset of infarction, and had a higher risk profile, as compared to primary/facilitated PTCA patients; both recanalization and reperfusion were less satisfactory, as were the outcomes. Thrombolysis is often ineffective but, as long as it remains a widespread treatment, efforts should be made to improve reperfusion and survival in these patients, possibly by an earlier referral for rescue PTCA.     

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.


Keywords: stenting; angioplasty; myocardial infarction; cost-benefit analysis     

Retrospective comparative study of primary intracoronary stenting versus balloon angioplasty for acute myocardial infarction

Balloon angioplasty has been shown to be an effective therapy for the treatment of acute myocardial infarction but is associated with a high restenosis rate, substantial early recoil, persistent thrombus and need for intracoronary thrombolysis, and a high rate of reclosure. Because many of the limitations of balloon angioplasty in the noninfarction setting are addressed by intracoronary stenting, we examined the results of primary stenting of 18 consecutive patients treated for acute myocardial infarction, and compared the results to those achieved with primary balloon angioplasty in 18 prior cases. Despite the presence of thrombus prior to angioplasty in 13 of the stented patients, no intracoronary thrombolytic therapy was required. Mean percent stenosis using quantitative coronary angiography was 17.7 ± 10.2% after primary stenting compared with 43.7 ± 20.3% after primary balloon angioplasty (P < .001). One stent patient who had all anticoagulant and antiplatelet therapy withdrawn early suffered subacute thrombosis. Patients were followed up to 3 yr. Complications were similar in the two groups. We conclude that primary stenting for acute myocardial infarction results in superior angiographic appearance as well as resolution of thrombus without the need for routine thrombolysis, and is associated with a low complication rate and excellent short-term clinical patency. Cathet. Cardiovasc. Diagn. 40:235–239, 1997. © 1997 Wiley-Liss, Inc.     

Cardioprotective effects of magnesium sulfate in patients undergoing primary coronary angioplasty for acute myocardial infarction.

BACKGROUND: Experimental evidence indicates that magnesium sulfate may have potential cardioprotective properties as an adjunct to coronary reperfusion. The present study was designed to examine the hypothesis that magnesium might have beneficial effects on left ventricular (LV) function and coronary microvascular function in patients with acute myocardial infarction (AMI). METHODS AND RESULTS: The study population of 180 consecutive patients with a first AMI (anterior or inferior) underwent successful primary coronary intervention. Patients were randomized to treatment with either intravenous magnesium (magnesium group, n=89) or normal saline (control group, n=91). Pre-discharge left ventriculograms were used to assess LV ejection fraction (LVEF), regional wall motion (RWM) within the infarct-zone and LV end-diastolic volume index. The Doppler guidewire was used to assess coronary flow velocity reserve (CFVR) as an index of coronary microvascular function. Magnesium group subjects showed significantly better LV systolic function (LVEF 63+/-9% vs 55+/-13%, p<0.001; RWM: -1.01+/-1.29 SD/chord vs -1.65+/-1.11 SD/chord, p=0.004), significantly smaller LV end-diastolic volume index (63+/-17 ml/m(2) vs 76+/-20 ml/m(2), p<0.001), and significantly higher CFVR (2.95+/-0.76 vs 2.50+/-0.99, p=0.023) than controls. CONCLUSION: Magnesium sulfate as an adjunct to primary coronary intervention shows favorable functional outcomes in patients with AMI.     

Early use of pravastatin in patients with acute myocardial infarction undergoing coronary angioplasty

AIM: To determine whether statin therapy initiated early in acute myocardial infarction together with thrombolytic therapy in patients with acute myocardial infarction results in clinical benefit through early plaque stabilization. METHODS AND RESULTS: The study population consisted of 77 patients who underwent coronary balloon angioplasty of the infarct-related artery during the first month of acute myocardial infarction. These patients belonged to the cohort of the Pravastatin Turkish Trial (PTT). Forty of them were assigned randomly to have immediate pravastatin (40 mg/day) therapy adjunctive to thrombolytic therapy regardless of serum lipid levels and received statin treatment throughout the study. Lipid levels were determined immediately after admission and before angioplasty and at the end of 6 months. Patients were re-evaluated clinically and angiographically for cardiovascular adverse events and restenosis after a 6-month follow-up period.The baseline angiographic and clinical characteristics of the two groups were similar.The incidence of angina was significantly lower in the pravastatin group (30.0%, 12 patients) compared to the control group (59.5%, 22 patients) (p = 0.018).The cumulative major adverse cardiac events in the pravastatin group were significantly lower when compared to the control group (32.5% vs. 75.6%, p = 0.0001). CONCLUSIONS: Early initiation of pravastatin therapy immediately after an acute myocardial infarction significantly decreased the frequency of major cardiac adverse events. Such early potential clinical benefits further strengthen the rationale for starting statin treatment as soon as possible after acute coronary events particularly in patients in whom invasive intervention is planned.