Coronary stenting in patients undergoing percutaneous transluminal coronary angioplasty during acute myocardial infarction

Effects of dabigatran regulates no‑reflow phenomenon in acute myocardial infarction mice through anti‑inflammatory and anti‑oxidative activities and connective tissue growth factor expression

Pradaxa is a novel oral anticoagulant, which was originally used to prevent thrombosis following joint replacement surgery. The aim of the current study was to investigate the effect dabigatran on acute myocardial infarction through regulating no‑reflow phenomenon and oxidative stress, neutrophil intraplaque infiltration and apoptosis. In the present study, dabigatran significantly inhibited the infarct size, increased arterial pressure and reduced no‑reflow phenomenon in acute myocardial infarction (AMI) vehicle rabbits. Treatment with dabigatran significantly inhibited the P65 of nuclear factor κB, tumor necrosis factor α, interleukin (IL)‑1β and IL‑6 activities and significantly enhanced the catalase and superoxide dismutase activities in the AMI rabbits. In addition, dabigatran significantly suppressed inducible nitric oxide synthase (iNOS), collagen I, transforming growth factor β1 (TGF‑β1), α‑smooth muscle actin (α‑SMA) and connective tissue growth factor (CTGF) protein expression in AMI rabbits. Taken together, these results suggest that the effects of dabigatran inhibit no‑reflow phenomenon, infarct size and enhance arterial pressure in AMI through anti‑inflammatory and anti‑oxidative activity, and regulating iNOS, collagen I, TGF‑β1, α‑SMA and CTGF protein expression in AMI rabbits.

Staged revascularization in critically ill patients with coronary artery disease

BACKGROUND

Critically ill patients undergoing bypass surgery experience a higher mortality and morbidity.

HYPOTHESIS

The study was undertaken to evaluate the efficacy and value of percutaneous transluminal coronary angioplasty (PTCA) as a bridge to coronary artery bypass graft surgery (CABG) in high-risk patients with refractory unstable angina or cardiogenic shock.

METHODS

We present 11 seriously unstable patients with severe multivessel coronary artery disease undergoing culprit vessel PTCA. Angioplasty was performed not as a definitive procedure but rather as a bridge to surgical revascularization. All the patients had sustained at least one myocardial infarction prior to catheterization, all had refractory unstable angina, eight patients had only a single patent coronary artery, and five patients were in cardiogenic shock.

RESULTS

Following PTCA, all patients enjoyed a stable in-hospital period. One patient died 12 weeks after successful PTCA while awaiting second CABG. Seven patients subsequently underwent CABG and are doing well. The remaining three patients were also advised to undergo CABG, but elected to continue medical management.

CONCLUSIONS

Coronary angioplasty of the culprit vessel may play a role as a bridge to surgery in critically ill patients.

[Acute coronary syndrome: unstable angina and myocardial infarction]

The acute coronary syndrome comprises unstable angina, non-ST-segment elevation myocardial infarction, and ST-segment elevation myocardial infarction. A successful and stable revascularisation of the infarct related vessel, and the prevention of the loss of myocardium are the main therapeutic targets, as cardiovascular mortality and long term quality of life are essentially determined by left ventricular function. The clinical diagnosis comprises clinical symptoms, ECG-changes, and cardiac troponins. Early percutaneous coronary intervention (PCI) has become the most common method of coronary revascularisation. If PCI is not available, systemic thrombolysis is an alternative after exclusion of contraindications. Parenteral anticoagulation with intravenous or subcutaneous heparines, antithrombotic therapy and HMG-CoA reductase inhibitors are the common secondary drug therapy. Moreover, to prevent left ventricular remodelling ACE-inhibitors, angiotension 2-receptor antagonists, and beta-blocker are indicated.

Primary stenting produces earlier and more efficient myocardial reperfusion than primary PTCA alone in patients with acute ST segment elevation MI

Restoration of blood flow in the infarct-related artery and subsequent myocardial reperfusion are major goals of both thrombolysis and primary percutaneous interventions. Whether percutaneous transluminal coronary angioplasty (PTCA) with immediate stenting (primary stenting) produces reperfusion more rapidly than primary PTCA alone is uncertain. This study determines whether primary stenting produces earlier myocardial reperfusion than primary PTCA alone in patients with acute ST segment elevation myocardial infarction using troponin T release kinetics. Primary stenting was performed on 60 patients and primary PTCA alone on 44 patients with typical ischemic chest pain and greater than 1.5 MV ST segment elevation in more than 2 contiguous electrocardiographic leads. Serum troponin T concentrations were measured before and after intervention; every 6 hours for 24 hours; then at 36, 48 and 72 hours. The mean time from onset of chest pain to peak serum troponin T concentration was 7.8 +/- 2.7 hours after primary stenting and 14.5 +/- 4.4 hours after primary PTCA (p < 0.0005). The mean peak serum troponin T concentration was 9.8 +/- 6.3 ng/dL after primary stenting and 13.6 +/-6.4 ng/dL after primary PTCA (p < 0.012). A significant univariate association with time to peak concentration of serum troponin T was identified for primary stenting (p < 0.0005), time from onset of chest pain to intervention (p < 0.04), and diabetes mellitus (p < 0.01). The only significant univariate marker associated with peak concentration of serum troponin T was primary stenting (p < 0.012). Multivariate analysis indicated that primary stenting (p < 0.0005), time from onset of chest pain to intervention (p < 0.048), and diabetes mellitus (p < 0.022) significantly influenced time to peak serum concentration or troponin T. Primary stenting produces earlier myocardial reperfusion than primary PTCA in patients with acute ST segment elevation myocardial infarction.

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.

Usefulness of intracoronary angioscopy for elucidating the cause of subacute thrombosis after stenting

Stent thrombosis is rare with anti-platelet therapy, which consists of aspirin and ticlopidine as a post-stenting administration. A 77-year-old man had repeated stent thrombosis, which was not predicted by coronary angiography, despite using contemporary periprocedural anti-platelet therapy. Only intravascular fiberscopy was able to detect the cause of the stent thrombosis.

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.

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.

[One-year clinical and angiographic follow-up after primary stenting]

INTRODUCTION AND OBJECTIVES

The late reocclusion or restenosis rate of the infarct related artery is frequent after primary angioplasty. An implanted stent may be able to improve the coronary angioplasty results and long-term outcome of these patients. We present the clinical and angiographic outcome of a cohort of patients treated with primary stenting.

PATIENTS AND METHODS

A group of 74 consecutive patients with acute myocardial infarction treated with primary angioplasty and stenting were followed for one year. An angiographic control was performed at the 6th month of follow-up in 91% of patients to assess the restenosis and reocclusion rates of the infarct-related artery.

RESULTS

There were eight in-hospital deaths and three during follow-up (mortality rate 14.8%) and one non-fatal reinfarction (1.5%). The cumulative rate of recurrent ischemia was 6% at 3 months and 15% at 6 months, without any further increment at one-year follow-up. A new angioplasty was performed in 7 patients and three patients underwent surgical revascularization. Thus 80% of patients after discharge were free of events. The angiographic control showed only one reocclusion of the infarct related artery and a restenosis rate of 27%.

CONCLUSIONS

These results show that primary stenting is an effective procedure in treating non-selected patients with acute myocardial infarction with a low long-term incidence of adverse events and a low restenosis rate.

[Results of coronary stenting in acute myocardial infarction]

OBJECTIVE

To describe the angiographic results and the in-hospital clinical outcome of patients with an acute phase of myocardial infarction treated with coronary angioplasty and stent placement.

METHODS

268 patients with myocardial infarction were treated with angioplasty and coronary stenting within in our center 12 hours after the onset of symptoms from January in 1992 to March 1998. 366 stents were placed (1.4 +/- 0.7 per patient), 35% being Palmaz-Schatz, 26% Wiktor, 21% Multi-Link and 18% others. Stenting was elective in 171 patients (64%), and the majority of patients (91%) were treated with aspirin plus ticlopidine.

RESULTS

A successful angiographic result was achieved in 258 patients (96%). Minimum lumen diameter was increased from 0.2 +/- 0.3 to 2.7 +/- 0.7 mm (p < 0.001), and stenosis decreased from 94 +/- 8% to 13 +/- 11% (p < 0.001). Mortality was 15.3% (3.2%, 24.4% and 67.7% in patients in Killip class I, II-III and IV, respectively). Nonfatal reinfarction and recurrent ischemia rates were 2.6% and 9%, respectively. Stent thrombosis occurred in 8 patients (3.0%), and new target vessel revascularization was needed in 12 (4.5%).

CONCLUSIONS

Stent placement in acute myocardial infarction is associated with high angiographic success rate, as well as a good in-hospital outcome. Mortality is localized, especially in patients with cardiac failure at the beginning of the procedure.

Risk predictors in patients scheduled for percutaneous coronary revascularization

Traditionally, procedural risks associated with conventional balloon coronary angioplasty have been largely attributed to unfavorable lesion morphology. However, factors predicting adverse events in the current practice of percutaneous coronary revascularization are unclear. The present study was undertaken to determine factors predicting major adverse events (death or Q-wave myocardial infarction or emergency bypass surgery) in 3,335 consecutive patients undergoing percutaneous coronary revascularization in the current practice of percutaneous coronary revascularization. During the period of observation, the rate of lesions treated successfully increased from 91% to 95% (P < 0.0001), whereas the rate of major adverse events (MACE) decreased from 3.6% to 1.6% (odds ratio [OR], 0.70 per year). Using multiple stepwise logistic regression analysis, cardiogenic shock (OR, 8.59; confidence interval [CI], 4.27-17.27), renal disease (OR, 3.33; CI, 1.95-5.69), evolving myocardial infarction (OR, 2.80; CI, 1.47-5.31), congestive heart failure (OR, 2.18; CI, 1.23-3.86), total number of lesions treated (OR, 1.28; CI, 1.03-1.59), age (OR, 1.03; CI, 1.01-1.06), and history of prior coronary intervention (OR, 0.51; CI 0.26-0.99) were identified as independent predictors of MACE. In addition, vascular disease (OR, 2. 48; CI 1.37-4.50) and unstable angina pectoris (OR, 0.44; CI 0.25-0. 79) were related to adverse events when patients in cardiogenic shock were excluded from the model. With the exception of most unfavorable lesion morphology (AHA/ACC lesion type C; OR, 2.05; CI, 1.19-3.52), anatomic parameters added no further information. In the present era of device technology, success rates of percutaneous coronary revascularization procedures have increased and remain to be determined by lesion morphology. In contrast, the rate of MACE is declining and best predicted by easily identified patient characteristics.

The role of coronary angioplasty and stenting in acute myocardial infarction

Despite the improvements in the pharmacological treatment of acute myocardial infarction, it is recognised that thrombolysis fails to reproduce reperfusion in a significant proportion of patients. Coronary interventional techniques have been shown to offer an alternative reperfusion strategy. There is increasing evidence that mechanical reperfusion may offer significant advantages over established thrombolytic therapy.

Primary coronary infarct artery stenting in acute myocardial infarction

Completed and ongoing randomized trials have provided results that favor primary infarct-related artery (IRA) stenting as opposed to primary percutaneous transluminal coronary angioplasty, but the applicability of the trial results to all patients with acute myocardial infarction (AMI) has not yet been investigated. This study sought to determine the applicability of an unconditional IRA stenting strategy in nonselected patients with AMI. After successful mechanical recanalization of the IRA, all patients with AMI and a reference diameter > or =2.5 mm were considered eligible for primary IRA stenting without any restriction regarding age or clinical status on presentation. The primary end point of the study was a composite end point defined as death, reinfarction, or repeat target lesion revascularization. Primary IRA stenting was successfully performed in 161 of 190 consecutive patients with AMI (85%), and of 162 (99%) considered suitable for stenting. Patients with nonstented IRA had a reference IRA diameter smaller than patients with a stent (2.71+/-0.48 vs 3.20+/-0.41 mm, p <0.001). Overall, the 6-month mortality was 5%. Mortality was 2% for patients without, and 32% for patients with cardiogenic shock. The incidences of reinfarction and of repeat target lesion revascularization were 1% and 12%, respectively. The 6-month angiographic follow-up showed an IRA patency rate of 94% and a restenosis rate of 26%. The results of this study strengthen the hypothesis that unconditional primary IRA stenting is highly feasible, and may actually improve the outcome of patients with AMI.

Current role of stenting in acute myocardial infarction

Primary infarct artery stenting has the potential to advance treatment of acute myocardial infarction. The postulated mechanisms of the benefit of stenting in acute myocardial infarction are the achievement of an acute optimal angiographic result and correction of any residual dissection to decrease the incidence of early and late restenosis and reocclusion and of the correlated events such as fatal and nonfatal reinfarction and repeat target vessel revascularization for recurrent ischemia. The results of 5 completed randomized trials comparing primary stenting with primary percutaneous transluminal coronary angioplasty show a lower incidence of the composite end point of death, myocardial infarction, and repeat target vessel revascularization in the stent groups as compared with the angioplasty groups and support the more extensive use of stents in patients with acute myocardial infarction. The efforts of the next years will be focused on further refinement of stent design and composition and the evaluation of pharmacological agents effective in restoring myocardial reperfusion to the fullest extent.

Coronary stenting during rescue angioplasty after failed thrombolysis

Compared with primary angioplasty [percutaneous transluminal coronary angioplasty (PTCA)], rescue PTCA is associated with lower angiographic success and higher reocclusion rates, especially after thrombolysis with tissue-type plasminogen activator (tPA). Although stent placement during primary PTCA has been demonstrated to be safe and even to improve the angiographic results achieved by balloon-alone PTCA, there are few data on stent placement during rescue PTCA after failed thrombolysis. This study sought to assess the feasibility and safety of stent implantation during rescue angioplasty in myocardial infarction after failed thrombolysis. The study population consisted of 20 patients with acute myocardial infarction referred for rescue PTCA after failed thrombolysis consecutively treated with coronary stenting. The thrombolytic agent was tPA in 15 patients (75%), streptokinase in 1 (5%), and anisoylated streptokinase plasminogen activator complex (APSAC) in 1 (5%); 3 patients (15%) were included in the INTIME II study (tPA vs. lanoteplase). After stenting, aspirin 200 mg daily plus ticlopidine 250 mg b.i.d. were administered. Thirty stents (1.5+/-1.0 per patient) were implanted. Angiographic success was achieved in 19 patients (95%). Two patients (10%) died, both because of severe bleeding complications. One patient (5%) suffered a reinfarction, but no patients suffered postinfarction angina or needed new target vessel revascularization. Eighteen patients (90%) were discharged alive and free of events. All these patients remained asymptomatic and free of target vessel revascularization at 6-month follow-up. Stent placement during rescue PTCA after failed thrombolysis is feasible and safe and is associated with a good angiographic result and clinical outcome. Bleeding complications seem to be, however, the main limitation of this reperfusion strategy.

Differences in TIMI frame count following successful reperfusion with stenting or percutaneous transluminal coronary angioplasty for acute myocardial infarction

The Thrombolysis In Myocardial Infarction (TIMI) flow grade achieved in the infarct-related artery (IRA) during reperfusion therapy for acute myocardial infarction (AMI) is directly related to myocardial salvage. Recently, several series have demonstrated the safety of stenting in AMI and documented a larger postprocedure luminal diameter than that found at angioplasty, although no study has compared the effect of PTCA and stenting in AMI on flow characteristics of the IRA. The residual stenosis and the number of frames required to opacify standardized angiographic landmarks normalized for vessel length (corrected TIMI frame count) or compared with flow in a corresponding normal coronary artery (TIMI frame count index) were determined for the IRA of 39 patients who underwent angioplasty or stenting for AMI. Baseline characteristics were similar for the 20 patients who underwent stenting and the 19 patients who underwent percutaneous transluminal coronary angioplasty. After intervention, the luminal diameter was greater (3.24 vs 2.09 mm, p <0.0001) and the residual stenosis was less (-9.4% vs. 26.7%, p <0.0001) after stenting than after percutaneous transluminal coronary angioplasty. These changes in vessel geometry were associated with a lower corrected TIMI frame count (16.1 vs 30.7, p <0.002) and a lower TIMI frame count index (0.68 vs 1.3, p <0.002). Thus, stenting in AMI is associated with a greater postprocedure luminal diameter and improvement in coronary blood flow as measured by the TIMI frame count method.

Coronary stent implantation in acute myocardial infarction

BACKGROUND

The purpose of this study was to provide an overview on stenting in acute myocardial infarction (MI).

METHODS AND RESULTS

A search of MEDLINE and the scientific sessions abstracts in peer review journals through May 1998 was carried out to identify any publications on stenting in MI. The settings were retrospective and prospective case series on stenting in MI, nonrandomized and randomized trials comparing primary stenting and primary percutaneous transluminal coronary angioplasty (PTCA) in MI, and stenting in cardiogenic shock complicating MI. Reported outcomes included procedural success, reocclusion, restenosis, and target vessel revascularization rates; incidence of death, MI, recurrent ischemia, major bleeding, and vascular complications; and incidence of cerebrovascular accidents. Procedural success rates were better for stenting than primary PTCA, and postprocedural minimum luminal diameters were larger. This resulted in lower reocclusion and restenosis rates and a lesser need for target vessel revascularization with primary stenting. The incidence of death, MI, and recurrent ischemia was also reduced with primary stenting. Major bleeding and vascular complications were confined to patients receiving anticoagulation as opposed to antiplatelet agents after stenting. Finally, a strategy of bailout stenting for failed PTCA in MI appears to be inferior to a primary stenting strategy.

CONCLUSIONS

Stenting in MI is an effective and safe reperfusion strategy with many advantages compared with primary PTCA.

Primary stenting in acute myocardial infarction: a 30-day follow up study

Primary coronary stenting is being increasingly used in patients undergoing primary coronary angioplasty for acute myocardial infarction. In this prospective study we evaluated our experience of direct angioplasty in 68 patients with acute myocardial infarction of whom 57 received intracoronary stents using high-pressure deployment (> or =12 atmospheres) with adjunct aspirin and ticlopidine therapy without coumadin. All patients underwent pre-discharge follow-up angiography. Stent implantation was successful in all patients. Stent thrombosis was not seen in any patient. However, TIMI grade 3 flow was obtained in only 51 patients (89.6%) with evidence of slow flow present in remaining six patients. Follow-up angiograms showed no stent thrombosis but five out of the six patients (83%) with slow-flow phenomenon persisted to have slow flow. These patients had lower left ventricular ejection fraction as compared to patients with TIMI 3 flow at follow-up angiography (27.5 +/- 10.2% vs. 42.1 +/- 15.2%, P < .001) and a high mortality (two out of six) within 30 days. Primary stenting is safe and feasible in the majority of patients with good short-term outcomes, but persistent slow-flow phenomenon with adverse clinical outcome is seen in a small but significant number of patients.

Hospital outcome after bailout coronary stenting in patients with acute myocardial infarction

We evaluated the outcome of bailout coronary stenting in acute myocardial infarction. Fifty patients (35 men, mean age 60 plusmn; 12) with acute myocardial infarction consecutively underwent bailout stenting after primary and rescue coronary angioplasty (n=41 and 9, respectively). Cardiogenic shock was present in six patients, and 17 others had contraindications to thrombolysis. Stent implantation was successful in 49/50 patients. The antithrombotic regimen combined heparin, aspirin, and ticlopidine. One patient had symptomatic stent closure. Predischarge angiography in 41/44 survivors showed widely patent stents in 40/41 patients. Six patients (4 of whom had been admitted with cardiogenic shock) died in the hospital. During acute myocardial infarction, bailout stenting can achieve high TIMI grade 3 coronary patency (here, 92%), and low acute stent closure rates (here, 2%). However, in-hospital mortality remained high, at nearly 10%, mainly due to the severe risk profile in this patient subset.

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

BACKGROUND

Although the benefits of primary angioplasty in acute myocardial infarction have been demonstrated, several areas for improvement remain. Therefore, a prospective randomized trial comparing primary stenting with balloon angioplasty in patients with acute myocardial infarction was conducted.

METHODS AND RESULTS

Patients with acute myocardial infarction were randomly assigned to undergo either primary stenting (n=112) or balloon angioplasty (n=115). The clinical end points were death, recurrent infarction, subsequent bypass surgery, or repeat angioplasty of the infarct-related vessel. The overall mortality rate at 6 months was 2%. Recurrent infarction occurred in 8 patients (7%) after balloon angioplasty and in 1 (1%) after stenting (P=0.036). Subsequent target-vessel revascularization was necessary in 19 (17%) and 4 (4%) patients, respectively (P=0.0016). The cardiac event-free survival rate in the stent group was significantly higher than in the balloon angioplasty group (95% versus 80%; P=0.012).

CONCLUSIONS

In selected patients with acute myocardial infarction, primary stenting can be applied safely and effectively, resulting in a lower incidence of recurrent infarction and a significant reduction in the need for subsequent target-vessel revascularization compared with balloon angioplasty.

In-hospital and late results of coronary stents versus conventional balloon angioplasty in acute myocardial infarction (GRAMI trial). Gianturco-Roubin in Acute Myocardial Infarction

One hundred four patients presenting with acute myocardial infarction < 24 hours after onset were randomized to 2 groups: group I (n = 52) was treated with balloon angioplasty followed electively with Gianturco Roubin II stents, and group II was treated with conventional balloon angioplasty alone (n = 52). All lesions were suitable for stenting. Baseline clinical, demographic, and angiographic characteristics were similar in the 2 groups. Procedural success was defined as no laboratory death or emergent coronary bypass, Thrombolysis In Myocardial Infarction (TIMI) trial 2 or 3 flow after the procedure in a culprit vessel, and a residual stenosis < or = 30% for coronary angioplasty and < 20% for stent. Procedural success was 98% in group I versus 94.2% in group II, p = NS. Thirteen patients in group II (25%) had bailout stenting during the initial procedure. Adverse in-hospital events including either death, nonelective coronary bypass, recurrent ischemia, and reinfarction occurred in 3.8% in group I versus 19.2% in group II, p = 0.03. Repeat angiography performed routinely before hospital discharge revealed TIMI 3 flow in the infarct-related artery in 98% in group I versus 83% in group II, p < 0.03. At late follow-up, event-free survival was significantly better in the stent (83%) than in the coronary angioplasty (65%) group (p = 0.002). The procedural in-hospital and late outcomes of this randomized study demonstrate that balloon angioplasty followed electively by coronary stents can be used as the primary modality for patients undergoing coronary interventions for acute myocardial infarction, increasing TIMI 3 flow, reducing in-hospital adverse events, and improving late outcome compared with balloon angioplasty alone.

A clinical trial comparing primary stenting of the infarct-related artery with optimal primary angioplasty for acute myocardial infarction: results from the Florence Randomized Elective Stenting in Acute Coronary Occlusions (FRESCO) trial

OBJECTIVES

This study sought to compare stenting of the primary infarct-related artery (IRA) with optimal primary percutaneous transluminal coronary angioplasty (PTCA) with respect to clinical and angiographic outcomes of patients with an acute myocardial infarction.

BACKGROUND

Early and late restenosis or reocclusion of the IRA after successful primary PTCA significantly contributes to increased patient morbidity and mortality. Coronary stenting results in a lower rate of angiographic and clinical restenosis than standard PTCA in patients with angina and with previously untreated, noncomplex lesions.

METHODS

After successful primary PTCA, 150 patients were randomly assigned to elective stenting or no further intervention. The primary end point of the trial was a composite end point, defined as death, reinfarction or repeat target vessel revascularization as a consequence of recurrent ischemia within 6 months of randomization. The secondary end point was angiographic evidence of restenosis or reocclusion at 6 months after randomization.

RESULTS

Stenting of the IRA was successful in all patients randomized to stent treatment. At 6 months, the incidence of the primary end point was 9% in the stent group and 28% in the PTCA group (p=0.003); the incidence of restenosis or reocclusion was 17% in the stent group and 43% in the PTCA group (p=0.001).

CONCLUSIONS

Primary stenting of the IRA, compared with optimal primary angioplasty, results in a lower rate of major adverse events related to recurrent ischemia and a lower rate of angiographically detected restenosis or reocclusion of the IRA.

Comparison of primary coronary stenting to primary balloon angioplasty with stent bailout for the treatment of patients with acute myocardial infarction

This study compares the immediate and long-term outcomes of a primary coronary stenting strategy with primary balloon angioplasty with stent bailout in the treatment of patients with acute myocardial infarction (AMI). One hundred forty-seven consecutive patients who underwent primary balloon angioplasty with stent bailout (n = 94) or primary stenting (n = 53) for AMI were clinically followed for 8.1 +/- 5.7 and 8.5 +/- 4.5 months, respectively. Immediate results, as well as in-hospital and long-term ischemic events (death, reinfarction, and repeat revascularization) were compared between both groups. Angiographic success was 91.5% in the balloon angioplasty group and 94% in the stent group. In-hospital and late follow-up combined ischemic events were 22 of 94 (23%) versus 0 of 53 (0%); p < 0.001 and 33 of 78 (42%) versus 13 of 53 (25%), p = 0.04 for the balloon angioplasty and stent groups, respectively. At 6 months, the cumulative probability of repeat target lesion revascularization was higher in the balloon angioplasty group (47% vs 18%, p = 0.0006) as was the probability of late target revascularization (36% vs 18%, p = 0.046); the cumulative event-free survival after 6 months was significantly lower in the balloon angioplasty group (44% vs 80%, p = 0.0001). This study demonstrates that a primary stent placement strategy in patients with AMI is safe, feasible, and superior to primary balloon angioplasty with stent bailout. Primary stenting results in a larger postprocedural minimal luminal diameter, a lower early and late recurrent ischemic event rate, and a lower incidence of target lesion revascularization at follow-up.

Late clinical and angiographic follow-up after stenting in evolving and recent myocardial infarction

OBJECTIVES

This study sought to assess the late clinical and angiographic outcomes of patients who received stents within the first week of acute myocardial infarction (AMI).

BACKGROUND

Recent studies have demonstrated that stenting of the infarct-related artery is a useful adjunct to balloon angioplasty in patients with AMI. However, there are limited data on the late clinical and angiographic outcomes of these patients.

METHODS

Between January 1994 and September 1995, 32 patients at our institution underwent stenting of the infarct-related artery within 1 week of AMI: 13 within 14 hours (evolving group) and 19 between days 2 and 7 (recent AMI group). Late clinical follow-up was obtained on all survivors. Quantitative angiographic measurements were recorded on the stented segments before stenting, immediately after stenting, and on the follow-up angiograms.

RESULTS

At 13.1+/-6.4 months from the time of stenting, three patients died and three required repeat angioplasty, but no patient had reinfarction or required bypass surgery. At follow-up 26 (81%) of 32 patients remained free of major cardiac events; of these, 24 (92%) were free of angina. Repeat angiography performed at 10.8+/-7.5 months in 26 (87%) of 30 discharged patients showed that all infarct-related arteries were patent and the restenosis rate was low: 22% in the 13 patients with evolving AMI (<14 hours) and 12% in the 19 patients with recent AMI (days 2 through 7).

CONCLUSION

In this study stenting of the infarct-related artery in patients with evolving and recent AMI was associated with a favorable late clinical outcome. Patency of the infarct-related artery was well maintained, and the restenosis rate was low.

Percutaneous transluminal coronary angioplasty (PTCA) without on-site surgical facilities

BACKGROUND

Numerous publications from European and Canadian centres have documented the feasibility of performing percutaneous transluminal coronary angioplasty (PTCA) without on-site surgical facilities. The absolute need for surgical standby has been changing especially with the introduction of coronary stent for bailout situations. This practice may be applicable in Australian centres especially in the environment of long waiting lists and cost containment.

AIM

To review the safety of performing PTCA by experienced operators in two Melbourne hospitals without on-site surgical facilities.

METHODS

We reviewed data of all patients who had PTCA electively (with low and moderate risks) between July 1996 and January 1997 and in the setting of acute myocardial infarction (AMI) from January 1996 to January 1997. Surgical standby was available as 'next available room' basis in nearby centres. Immediate outcome before discharge was documented and follow up from three to six months in 80% of all surviving patients.

RESULTS

There were 46 elective PTCA and 41 PTCA for AMI. PTCA was successful in 82 (94%) patients. Among the elective cases, seven patients were already inpatients with unstable or postinfarct angina. Thirteen patients had stents deployed with three for acute closure. Abciximab (Reopro) was given to eight patients. Two patients had acute closure in the laboratory which could not be reopened, but did not require emergency coronary artery bypass grafting (CABG). There were four inhospital deaths (three related to AMI and one died of a noncoronary cause).

CONCLUSION

PTCA can be performed electively in a selected group of patients with coronary artery disease and as a primary procedure for AMI without on-site surgical standby.

Systematic direct angioplasty and stent-supported direct angioplasty therapy for cardiogenic shock complicating acute myocardial infarction: in-hospital and long-term survival

OBJECTIVES

This prospective observational study was conducted to examine the apparent impact of a systematic direct percutaneous transluminal coronary angioplasty (PTCA) strategy on mortality in a series of 66 consecutive patients with acute myocardial infarction (AMI) complicated by cardiogenic shock, and to analyze the predictors of outcome after successful direct PTCA.

BACKGROUND

Previous studies have reported encouraging results with PTCA in patients with AMI complicated by cardiogenic shock, but a biased case selection for PTCA may have heavily influenced the observed outcomes.

METHODS

All patients admitted with AMI were considered eligible for direct PTCA, including those with the most profound shock, and no upper age limit was used. The treatment protocol also included stenting of the infarct-related artery for a poor or suboptimal angiographic result after conventional PTCA.

RESULTS

Between January 1995 and March 1997, 364 consecutive patients underwent direct PTCA, and in 66 patients AMI was complicated by cardiogenic shock. In patients with cardiogenic shock, direct PTCA had a success rate of 94%; an optimal angiographic result was achieved in 85%; primary stenting of the infarct-related artery was accomplished in 47%; and the in-hospital mortality rate was 26%. Univariate analysis showed that patient age, chronic coronary occlusion and completeness of revascularization were significantly related to in-hospital mortality. The mean follow-up period was 16 +/- 8 months. Survival rate at 6 months was 71%. Comparison of event-free survival in patients with a stented or nonstented infarct-related artery suggests an initial and long-term benefit of primary stenting.

CONCLUSIONS

Systematic direct PTCA, including stent-supported PTCA, can establish a Thrombolysis in Myocardial Infarction (TIMI) grade 3 flow in the great majority of patients presenting with AMI and early cardiogenic shock. High performance criteria, including new devices such as coronary stents, should be considered in randomized trials where mechanical revascularization therapy is being tested.

Stent implantation in patient with visible intracoronary thrombus and compromised left ventricular function, after local thrombolysis using the Dispatch catheter

The case of a patient with unstable angina and angiographic findings of significant (approximately 90%) right coronary artery stenosis with an intracoronary thrombus next to the lesion, total left anterior descending and circumflex occlusion and an ejection fraction of approximately 22% is described. The case was treated with stent implantation after local thrombolysis with the use of the Dispatch infusion catheter.

Primary angioplasty for acute myocardial infarction

The use of thrombolytic therapy has been widely accepted for the treatment of acute myocardial infarction. Despite improving mortality, thrombolytic therapy may be contraindicated in many patients presenting with myocardial infarction and is associated with a small, yet significant risk of hemorrhagic sequelae. This article outlines the rationale behind reperfusion therapy, the use of pharmacological thrombolysis and the role of adjunctive angioplasty. The potential advantages of a therapeutic strategy of primary angioplasty, instead of thrombolysis, are discussed. These include anatomical definition, risk stratification, reduced recurrent ischemia, enhanced coronary perfusion and improved coronary patency. The randomized trials in which primary angioplasty and thrombolytic therapy were compared are reviewed. We conclude that angioplasty results in a reduction of short-term mortality and nonfatal reinfarction and therefore advocate the routine use of coronary angioplasty as a primary reperfusion strategy for acute myocardial infarction. The potential limitations of primary angioplasty in the community hospital setting are discussed. Finally, we examine the roles of adjunctive mechanical (e.g. stents) and pharmacological (e.g. Abciximab) means of further enhancing outcomes after primary angioplasty.

Clinical and angiographic implications of coronary stenting in thrombus-containing lesions

OBJECTIVES

This study sought to determine the results of coronary stenting in thrombus-laden lesions.

BACKGROUND

The angiographic evidence of intracoronary thrombus has classically been considered a formal contraindication to stent implantation. However, with increasing use of stenting, the indications for this technique have widened to include treatment of patients who have an acute coronary syndrome or lesions with adverse anatomic features.

METHODS

We studied 86 consecutive patients (mean age +/- SD 61 +/- 11 years, 14 women) undergoing coronary stenting of a thrombus-containing lesion; the procedure was performed electively in 39% and after angioplasty failure in 61%. Sixty-four patients (75%) were treated for unstable angina, and 19 (22%) underwent the procedure during an acute myocardial infarction. A specific protocol that included clinical and late angiographic follow-up was used.

RESULTS

Angiographic success was obtained in 83 patients (96%). Five patients (6%) died during the hospital stay despite angiographic success; four of these had cardiogenic shock, and one (1%) had subacute stent thrombosis. Non-Q wave myocardial infarction developed in five additional patients (6%), and four of these five had data consistent with distal embolization. Of the 78 patients discharged with angiographic success, 67 (86%) were event-free and clinically improved at last follow-up visit (12 +/- 11 months). During the follow-up period, eight patients required repeat angioplasty, one patient required heart transplantation, and two patients died. Quantitative angiography demonstrated excellent angiographic results after stenting (minimal lumen diameter 0.31 +/- 0.4 vs. 2.77 +/- 0.6 mm). Late angiographic follow-up (5.5 +/- 1 months) was obtained in 50 patients with 54 lesions (93% of eligible), revealing a minimal lumen diameter of 2.0 +/- 1 mm and restenosis (lumen narrowing > 50%) in 18 lesions (33%).

CONCLUSIONS

Coronary stenting constitutes an effective therapeutic strategy for patients with thrombus-containing lesions, either after failure of initial angioplasty or electively as the primary procedure. Coronary stenting in this adverse anatomic setting results in a high degree of angiographic success, a low incidence of subacute thrombosis and an acceptable restenosis rate.

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 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.