Current role of stenting in acute myocardial infarction

Comparison of long-term clinical outcomes of bioabsorbable polymer versus durable polymer drug-eluting stents: a systematic review and meta-analysis

BACKGROUND

One million individuals in the USA die from acute myocardial infarction (MI), which currently affects 3 million people globally. The available data about the early and late outcomes of both biodegradable polymer drug-eluting stents (BP-DES) and durable polymer drug-eluting stents exhibit inconsistency. We performed a meta-analysis comparing the safety and efficacy of BP-DES with DP-DES.

METHODS

PubMed, Google Scholar, EMBASE, Cochrane, Ovid Medline, and Clinical Trials.gov databases were used to find out studies comparing BP-DES to DP-DES. All the analyses used the random-effects model.

RESULTS

A total of 18 studies were incorporated in this meta-analysis that involved 28,874 patients, out of which 11,997 received the BP Stent, and the rest of 16,578 received the DP stent. Thorough analyses revealed that the risk of all-cause death was significantly higher in the BP-DES group (5.4% vs 2.7%) (RR 1.22, p 0.02) for two years or less than two-year follow-up. For studies with more than two years of follow-up, all-cause death was 9.07% (599/6603) in BP-DES and 9.47% (531/5602) in the DP-DES group but failed to achieve statistically significant levels (RR 0.97, p 0.58).

CONCLUSIONS

The study revealed no clinically significant (P value was > 0.05) differences in all-cause death, cardiac death, target lesion revascularization (TLR), late stent thrombosis, device-oriented composite endpoint/target lesion failure (DOCE/TLF), myocardial infarction (MI), target vessel MI, target vessel revascularization (TVR), target vessel infarction (TVI) between BP-DES and DP-DES for more than two years of follow-up. Additionally, all-cause death was only outcomes which found to have a statistically significant difference for less than two years of follow-up, while remaining were statistically non-significant.

Stenting in Acute STEMI Intervention

Stenting in acute myocardial infarction (AMI) has the benefits of achieving acute optimal angiographic results and correcting residual dissection to decrease the incidence of restenosis and reocclusion. Studies have shown that percutaneous transluminal coronary angioplasty for primary treatment after AMI is superior to thrombolytic therapy regarding the restoration of normal coronary blood flow. Coronary stenting improves initial success rates, decreases the incidence of abrupt closure, and is associated with a reduced rate of restenosis. In the presence of thrombus-containing lesions, coronary stenting constitutes an effective therapeutic strategy, either after failure of initial angioplasty or electively as the primary procedure.

[Long-term follow-up after primary angioplasty: is stenting beneficial?]

BACKGROUND

Primary stenting leads to a better short-term outcome than balloon angioplasty for acute myocardial infarction in randomised trials. However few data are available about the long-term outcome of primary stenting in acute myocardial infarction (AMI).

OBJECTIVES

The aim of this study was to compare the three-year outcome after primary stenting versus balloon angioplasty in patients with acute myocardial infarction.

METHODS

We conducted a retrospective study including 157 patients with AMI in a single center. Patients underwent balloon angioplasty (N = 48) or primary stenting (N = 109) within six hours after the onset of chest pain. We looked at the outcome during three years focusing on global mortality, major adverse cardiac events (MACE), reinterventions and target vessel revascularization (TVR).

RESULTS

The two groups are similar for their baseline characteristics. No difference was noted for in-patient mortality in the balloon angioplasty group and the primary stenting group (2.1 vs 2.8%; P = ns). The three-year mortality was not significantly different in the two groups. Regarding MACE (27.8 vs 31.7; P = 0.95), reinterventions (20.4 vs 24.7%; P = 0.98) and TVR (18.6 vs 17.8%; P = 0.69), both groups were statistically not different.

CONCLUSION

In the long-term patients treated with stent placement have similar rates of MACE, reinterventions or TVR than patients undergoing balloon angioplasty. If few studies noted a benefit in short-term outcomes, primary stenting doesn't improve the prognosis of acute myocardial infarction on long-term follow-up, which is dependent on atherosclerosis.

Coronary Angioplasty

Percutaneous revascularization is a widely accepted procedure to treat patients with coronary artery disease. Since its first description in the 1970s, significant technological and pharmaceutical advances have occurred and subsequently reduced the complications associated with the procedure. Large, randomized controlled trials have provided additional evidence that percutaneous revascularization improves morbidity and mortality in patients with coronary artery disease. Over the last decade, devices designed to treat patients with more complex coronary artery disease have expanded the available therapeutic options and will likely contribute to a further decline in adverse events. Despite these advances, the management of patients with acute myocardial infarction, in-stent restenosis, and multivessel coronary artery disease remains challenging. The majority of evidence supports an early, aggressive approach in patients with acute ST-elevation and non-ST-elevation myocardial infarction. Ongoing clinical trials should help to further define the role of percutaneous interventions in the optimal management of patients with coronary artery disease.

Relation of troponin T release kinetics to long-term clinical outcome in patients with acute ST segment elevation myocardial infarction treated with a percutaneous intervention

The purpose of this study was to determine the relation of troponin T release kinetics to long-term clinical outcome in patients with an acute ST segment elevation myocardial infarction treated with a primary percutaneous intervention. One hundred and four patients with typical ischemic chest pain and > 1.5 mm ST segment elevation in > 2 contiguous leads underwent primary stenting (n = 60) or primary percutaneous transluminal coronary angioplasty (n = 44). Serum troponin T concentrations were obtained prior to and serially postintervention for 72 hr. Mean time to peak serum troponin T concentration was significantly longer in patients with cardiac death (P = 0.02), reinfarction (P = 0.007), target lesion reintervention (P = 0.03), and the composite of these events (13.2 +/- 5.3 vs. 9.3 +/- 4.0 hr; P < 0.0005). Multivariate analysis identified age, Killip class > 2, and time to peak serum troponin T concentration as independent predictors of long-term cardiac event-free survival. Thus, time to peak serum troponin T concentration independently predicts long-term cardiac event-free survival in patients with acute ST segment elevation myocardial infarction treated with a primary percutaneous intervention.

Risk stratification in patients with inferior acute myocardial infarction treated by percutaneous coronary interventions: the role of admission troponin T

BACKGROUND

Cardiac troponin T (cTnT) elevations on admission indicate a high-risk subgroup of patients with ST-segment elevation acute myocardial infarction (AMI). This finding has been attributed to less effective reperfusion after thrombolytic therapy. The aim of this study was to determine the role of admission cTnT on the efficacy of percutaneous coronary interventions (PCIs) in inferior AMI.

METHODS AND RESULTS

One hundred fifty-nine consecutive patients with inferior ST-segment AMI were enrolled and followed up for a mean of 448 days. Patients were stratified by cTnT on admission. A cTnT >/=0.1 microg/L was found in 58% of patients. These patients had longer time intervals from onset of symptoms to therapy (P:<0. 001) and higher 30-day (10.8% versus 1.5%, P:=0.027) and long-term (17.2% versus 4.5%, P:=0.023) cardiac mortalities. Rates of the combined end point of death, nonfatal reinfarction, and need for repeated target vessel revascularization procedures were not different in cTnT groups (log rank, 0.69; P:=0.41). PCI was attempted in 93.3% of cTnT-positive and 98.5% cTnT-negative patients (P:=0.24) but was less frequently successful in patients with cTnT >/=0.1 microg/L (77.9% versus 96.9%, P:<0.001). Coronary stenting reduced 30-day and long-term cardiac mortality, particularly among cTnT-positive patients. In a multivariate analysis, cTnT indicated an approximately 5-fold-higher risk (adjusted OR, 4.6; 95% CI, 0.79 to 27.11; P:=0.089) and was a strong albeit not independent risk predictor.

CONCLUSIONS

In inferior AMI, a positive admission cTnT is associated with lower success rates of direct PCI and higher rates of cardiac events over the short and long term. These patients benefit from coronary stenting.