Long-term outcome of patients with very long stents for treatment of diffuse coronary disease

Culprit only versus complete coronary revascularization during primary PCI

BACKGROUND

Primary percutaneous intervention (PCI) is the treatment of choice for acute ST elevation myocardial infarction. Currently it is recommended to treat only the culprit artery during the acute procedure. Only few reports describe the results of simultaneous non-culprit vessel PCI. The study hypothesizes that complete revascularization during primary PCI can be achieved safely with an improved clinical outcome during the indexed hospitalization.

METHODS

One hundred and twenty consecutive patients presented with acute ST elevation myocardial infarction (STEMI) and multivessel coronary stenosis. Ninety five underwent complete revascularization (CR): the culprit artery was opened first followed by dilatation of the other significantly narrowed arteries. Twenty five had culprit only revascularization (COR): the culprit artery only was dilated and the other arteries were left untreated during the primary PCI.

RESULTS

Complete revascularization (CR) was associated with reduced incidence of major cardiac events (recurrent ischemia, reinfarction, acute heart failure and in-hospital mortality 16.7 versus 52%, P=0.0001). There was a significant lower rate of recurrent ischemic episodes (4.2% versus 32%, P=0.002), myocardial reinfarction (3.1% versus 16%, P=0.01), reintervention (7.3% versus 32%, P=0.001), acute heart failure (9.4% versus 32%, P=0.01) during the indexed hospitalization and shorter hospitalization (4.4+/-1.27 versus 9.6+/-2.3, P=0.001) in the CR group. Transient renal dysfunction was more common in CR patients (8.4% versus 4% P=0.01). In-hospital and one year mortality were similar between the two groups.

CONCLUSION

Multivessel PCI during acute myocardial infarction is feasible and safe. Complete revascularization resulted in an improved acute clinical course. These data support a policy of complete revascularization during primary PCI for STEMI.

Pathophysiology of coronary artery in-stent restenosis

In-stent restenosis reflects the interaction of a cascade of molecular and cellular events occurring within the vessel wall. Coronary stenting induces localized injury to the vessel wall, which leads to the release of thrombogenic, vasoactive, and lymphocytes mitogenic factors that result in processes causing re-narrowing at the injured site. Three major processes have been identified that lead to the in-stent restenosis: neointimal hyperplasia, elastic recoil, and negative arterial remodeling. The most important one is intimal hyperplasia. As the time course of neointimal hyperplasia is unknown, a causal relationship between the development of new blood vessels and clinical restenosis cannot be firmly established.

Inhibition of Restenosis With a Paclitaxel-Eluting, Polymer-Free Coronary Stent

BACKGROUND

The use of a stent to deliver a drug may reduce in-stent restenosis. Paclitaxel interrupts the smooth muscle cell cycle by stabilizing microtubules, thereby arresting mitosis.

METHODS AND RESULTS

On the basis of prior animal studies, the European evaLUation of the pacliTaxel Eluting Stent (ELUTES) pilot clinical trial (n=190) investigated the safety and efficacy of V-Flex Plus coronary stents (Cook Inc) coated with escalating doses of paclitaxel (0.2, 0.7, 1.4, and 2.7 microg/mm2 stent surface area) applied directly to the abluminal surface of the stent in de novo lesions compared with bare stent alone. The primary efficacy end point was angiographic percent diameter stenosis at 6 months. At angiographic follow-up, percent diameter stenosis was 33.9+/-26.7% in controls (n=34) and 14.2+/-16.6% in the 2.7-microg/mm2 group (n=31; P=0.006). Late loss decreased from 0.73+/-0.73 to 0.11+/-0.50 mm (P=0.002). Binary restenosis (> or =50% at follow-up) decreased from 20.6% to 3.2% (P=0.056), with no significant benefit from intermediate paclitaxel doses. Freedom from major adverse cardiac events in the highest (effective) dose group was 92%, 89%, and 86% at 1, 6, and 12 months, respectively (P=NS versus control). No late stent thromboses were seen in any treated group despite clopidogrel treatment for 3 months only.

CONCLUSIONS

Paclitaxel applied directly to the abluminal surface of a bare metal coronary stent, at a dose density of 2.7 microg/mm2, reduced angiographic indicators of in-stent restenosis without short- or medium-term side effects.

Synergy of Passive Coating and Targeted Drug Delivery:. The Tacrolimus-Eluting Janus CarboStent

Stents represent a major step forward in the treatment of coronary artery disease since the introduction of balloon angioplasty. They have demonstrated the reduction of angiographic indexes of restenosis and rates of repeat revascularization. However, in-stent neointimal proliferation represents the persisting limitation and challenge. Local delivery using a stent platform for deposition of therapeutic drug concentration in the arterial wall has emerged as an effective strategy to reduce in-stent neointimal hyperplasia and restenosis. The purpose of this article is to describe the design characteristics of a new drug-eluting stent. Its unique features consist of integral Carbofilm thromboresistant coating combined with the capability to load the drug into and to release it from deep sculptures made on the external surface of the stent. The advantages of this design are the possibility to load higher amounts of drug, to selectively deliver it to the vessel wall without loss in the blood stream, and to improve the biocompatibility and thromboresistance of the stent. Preclinical studies, using tacrolimus as the biological agent, showed excellent vessel tissue response and mild inflammation scores. A significant reduction of intimal proliferation was observed in comparison with a control stent. The enrollment in a safety first-in-man evaluation has been successfully completed. A randomized, double-blind, multicenter study is expected to start at the completion of the "safety" evaluation.

Stent placement for non-STRESS/BENESTENT lesions: a critical review

Stenting lesions with favorable characteristics as required for inclusion in the STRESS/BENESTENT trials have yielded superior results to that of PTCA alone. Results for less favorable lesions such as in small vessels, diffuse disease, ostial disease, and saphenous vein grafts are less well established. This review seeks to analyze available data for stent placement in this subset of non-STRESS/BENESTENT lesions.

Usefulness of stent length in predicting in-stent restenosis (the MULTI-LINK stent trials)

The cumulative experience of 4 clinical trials using the MULTI-LINK coronary stent design was analyzed. Multivariable logistic regression identified postprocedure in-stent minimum lumen diameter (p = 0.0001), stent length (p = 0.0038), smoking (p = 0.0105). and diabetes (p = 0.0803) as the most important predictors of in-stent restenosis at late (6- to 9-month) angiographic follow-up.