Novel Intravascular Ultrasound-Guided Method to Create Transintimal Arterial Communications: Initial Experience in Peripheral Occlusive Disease and Aortic Dissection

PURPOSE

To report our experience using a commercially available catheter-based system equipped with an intravascular ultrasound (IVUS) transducer to achieve controlled true lumen re-entry in patients undergoing subintimal angioplasty for chronic total occlusions (CTO) or aortic dissections.

METHODS

During an 8-month period, 10 patients (6 men; mean age 73.4 years) with lower extremity (LE) ischemia from CTOs (n=7) or true lumen collapse from aortic dissections (n=3) were treated. Subintimal access and controlled re-entry of the CTOs were performed with a commercially available 6.2-F dual-lumen catheter, which contained an integrated 64-element phased-array IVUS transducer and a deployable 24-G needle through which a guidewire was passed once the target lumen was reached. The occluded segments were balloon dilated; self-expanding nitinol stents were deployed. In the aortic dissections, fenestrations were performed using the same device, with the IVUS unit acting as the guide. The fenestrations were balloon dilated and stented to support the true lumen.

RESULTS

Time to effective re-entry ranged from 6 to 10 minutes (mean 7) in the CTOs; antegrade flow was restored in all 7 CTOs, and the patients were free of ischemic symptoms at up to 8-month follow-up. In the aortic dissection cases, the fenestrations equalized pressures between the lumens and restored flow into the compromised vessels. There were no complications related to the use of this device in any of the 10 patients.

CONCLUSIONS

Our preliminary results demonstrate the feasibility of using this catheter-based system for subintimal recanalization with controlled re-entry in CTOs and for aortic flap fenestrations in aortic dissections. This approach can improve the technical success rate, reduce the time of the procedure, and minimize potential complications.

Comparing performance between coronary intervention centres requires detailed case-mix adjusted analysis

This study compares 12 month clinical outcomes and procedural costs at two interventional centres with significant differences in crude mortality and revascularization outcomes between 1997 and 1998. Percutaneous coronary intervention (PCI) registry data on 1046 consecutive patients treated contemporaneously at two university centres were linked to hospital discharge and death data to provide 12 month follow-up information on survival and repeat revascularization. Costs were determined by detailed analysis of equipment use, length of stay and staff from 100 contemporary cases at each centre to derive a procedural cost model. This model was then applied retrospectively to estimate cost per procedure. Stents were used more frequently at one centre (56 versus 26 per cent, chi(2) test, p < 0.001) resulting in greater procedural cost [mean (SE), pounds sterling 1970 (34) versus pounds sterling 1521 (39), t-test, p < 0.001). One year repeat target vessel PCI was significantly greater at the centre using more stents (10.3 versus 5.6 per cent, chi(2) test, p = 0.005) and the need for any repeat revascularization (PCI or coronary artery by-pass surgery) was also significantly greater at this centre (18.4 versus 10.8 per cent, chi(2) test, p < 0.001). Cox regression revealed that after correction for case-mix the difference in the need for repeat target vessel PCI between the two centres was no longer significant (p = 0.15). In the two centres studied, crude differences in cost per case, mortality and the need for revascularization were largely accounted for by significant differences in case-mix. Comparison of outcomes and costs between centres should not be published without careful adjustment for differences in case-mix.

Primary coronary intervention in acute myocardial infarction

Percutaneous coronary intervention (PCI) with stent implantation has become the standard of care for acute myocardial infarction <12 hours from symptom onset. This has led to decreased morbidity and mortality both short and long term compared to thrombolytic therapy. Stent implantation has been demonstrated to be superior to balloon PCI for mechanical reperfusion of acute myocardial infarction. Intravenous antiplatelet glycoprotein IIb/IIIa inhibitors may have a role in improving TIMI flow prior to PCI and decreasing morbidity and mortality. The role of thrombolytics vs. IIb/IIIa inhibitors in "facilitated reperfusion" is unclear at this time and further research is needed to define the indication of adjunctive pharmacology.

High-Dose BoluS TiRofibAn and Sirolimus Eluting STEnt versus Abiciximab and Bare Metal Stent in Acute MYocardial Infarction (STRATEGY) Study—Protocol Design and Demography of the First 100 Patients

BACKGROUND

Primary bare metal stenting and abciximab infusion are currently considered the best available reperfusion strategy for acute ST-segment elevation myocardial infarction (STEMI). Sirolimus eluting stents (SES), compared to bare metal stent (BMS), greatly reduce the incidence of binary restenosis and target vessel revascularisation (TVR), but their use on a routine basis results in a significant increase in medical costs. With current European list prices, the use of tirofiban instead of abciximab would save enough money to absorb the difference between SES and BMS.

AIM

To assess whether in patients with STEMI the combination of SES with high dose bolus (HDB) tirofiban results in a similar incidence of major cardiovascular events (MACE) but in a lower binary restenosis rate after six months compared to BMS and abciximab.

METHODS AND RESULTS

160 patients are required to satisfy the primary composite end-point, including MACE and binary restenosis. The study is ongoing: the current paper focuses on the methodology and demography of the first 100 patients so far enrolled. Patients randomised to HDB tirofiban (n = 50, mean age: 62 +/- 12, 40 males) and abciximab (n = 50, mean age: 63 +/- 12, 38 males) do not differ for medical history, presentation profile, medications at discharge, angiographic profile and creatine-kinase MB-fraction at peak.

CONCLUSIONS

The results of the trial will be available by the end of 2004: they will be crucial for the cardiologists to know whether the gold standard for AMI treatment should be reconsidered after the introduction of SES into the clinical practice.

Endoscopic intubation with conventional plastic stents: a safe and cost-effective palliation for inoperable esophageal cancer

Access to expensive equipment and costly self-expanding metal endoprostheses is limited in some regions where unresectable esophageal cancer is not infrequent. The aim of this study was to review the long-term results of palliation of malignant esophageal obstruction using low-priced conventional plastic stents. One hundred sixty-nine patients with dysphagia due to inoperable esophageal cancer underwent esophageal intubation under endoscopic control alone, without general anesthesia, by the pulsion method. Stents mounted on their delivery device were inserted over an endoscopically placed guide wire. Improvement in swallowing was seen in all patients. Dysphagia scores have improved from 3.64 +/- 0.21 to 1.08 +/- 0.17. Major early procedure-related morbidity was high at 0.6% with one intramural perforation (no transmural perforation at all). Minimal mucosal bleeding was seen with 72 cases (42.6%). Procedure-related mortality was 0%. Late procedure-related complications requiring further endoscopic procedures occurred in 8.2% (tube occlusion: 5.3%, tube dislocation: 2.9%). Our 7-day mortality was 0% and 5 patients died within 30 days, usually from the disease itself. Those surviving the procedure (more than 7 days) had a mean survival of 209 days. Esophageal plastic stents can be accurately and safely placed under direct endoscopic control with lower costs. Therefore, endoscopic intubation remains a useful palliative treatment for patients with unresectable carcinoma of the esophagus.

Drug-eluting stents: new era and new concerns

At present there is much excitement about drug-eluting stents, which hold promise for the treatment of coronary artery disease. This ingenious therapy involves coating the outside of a standard coronary stent with a thin polymer containing medication that can prevent scarring at the site of coronary intervention. Early trials with sirolimus coated stents showed that they might prevent coronary artery restenosis, but later studies, involving more complex coronary lesions, did not show a complete absence of restenosis. Recent studies have demonstrated the long term cost effectiveness of drug-eluting stents as they have reduced the need for revascularisation procedures. At present there are few data on the safety and effectiveness of stents over follow up periods exceeding two years, and data obtained from animal models of stenting might not be completely applicable to humans. There are concerns that drug-eluting stents might delay, rather than inhibit, restenosis. Also there is concern regarding the inflammation caused by the polymer substrate. This article reviews the present data on drug-eluting stents and their benefits, shortcomings, and concerns.

Strategic savings. As supply costs climb, hospitals rethink their purchasing strategies

Surging prices for supplies are intensifying the pressure on hospitals already reeling from skyrocketing liability, staffing and technology costs. The prices for certain supplies far outstrip general inflation and, executives say, could undermine the financial viability of some service lines. That's forcing some hospitals to rethink their purchasing strategies.

[Acute coronary syndrome: ST-segment elevation infarct]

Management of acute myocardial infarction in patients presenting with ST-segment elevation has evolved considerably over the past decades. In this review, we will limit the discussion to STEMI, and describe some recent developments and new insights into the evidence base of various therapeutic options. We will address the contemporary antithrombotic approach to treatment of this disorder. The controversy regarding optimal treatment of ACS, whether invasive or conservative, is discussed. This seems all the mandatory more as many study populations are not directly comparable, and some therapies are nowhere at hand. Progressively important cost-benefit considerations are another aspect that makes the assessment of the evidence claimed difficult.

Three-Year Outcome After Coronary Stenting Versus Bypass Surgery for the Treatment of Multivessel Disease

Background— The primary results of Arterial Revascularization Therapy Study reported a greater need for repeated revascularization after percutaneous coronary intervention with stenting (PCI). However, PCI was less expensive than coronary artery bypass grafting (CABG) and offered the same degree of protection against death, stroke, and myocardial infarction.

Methods and Results— Patients with multivessel disease (n=1205) were randomly assigned to either CABG or PCI and followed up for up to 3 years. Survival rates without stroke or myocardial infarction were similar in each group at 1 year and 3 years (90.5% versus 91.4% for PCI versus CABG at 1 year and 87.2% versus 88.4% for PCI versus CABG at 3 years). However, the respective repeat revascularization rates were 21.2% and 26.7% at 1 and 3 years in patients allocated to PCI, compared with 3.8% and 6.6% in patients allocated to CABG ( P <0.0001). Diabetes ( P <0.0009) and maximal pressure for stent deployment ( P <0.002) are the strongest independent predictors of events at 3 years after PCI, whereas left anterior descending coronary artery grafting ( P <0.006) is the best predictor of event-free survival at 3 years after CABG. The incremental cost of surgery compared with PCI for an event-free patient was 19 257 at 1 year but decreased to 10 492 at 3 years. It remained at 142 391 at 3 years when revascularization procedures were excluded in the efficacy end point, however.

Conclusions— Three-year survival rates without stroke and myocardial infarction are identical in both groups, and the cost/benefit ratio of stenting is determined primarily by the increasing need for revascularization in the PCI group.

Economic impact of drug-eluting stents on hospital systems: a disease-state model

BACKGROUND

Drug-eluting intracoronary stents decrease restenosis and later revascularization. The US Department of Health and Human Services (HHS), recognizing the financial and clinical impact of this technology, recently proposed accelerated reimbursement to hospitals.

METHODS AND RESULTS

A disease state-transition computer model simulated the clinical and economic consequences to hospitals of drug-eluting stents over 5 years. Model parameters combined information from a longitudinal clinical database, a hospital cost-accounting system, and a survey instrument. Simulations were repeated 1000 times for each set of parameters. With 85% of stent procedures shifted to drug-eluting stents in the first year of availability, the mean number of repeat revascularizations dropped by 60.4% at year 5. With no changes in reimbursement policy, a hospital with a catheterization laboratory volume of 3112 patients yearly converted from a 2.01 million dollars (M) annual profit to an 8.10 M dollars loss in the first year (95% CI 8.09 M dollars to 8.12 M dollars) and 8.7 M dollars annual losses in later years. This represented an overall change in cash flow of 55.71 M dollars (95% CI 55.66 M dollars to 55.76 M dollars) away from the hospital over 5 years. The incremental reimbursement proposed by HHS reduced this loss to 4.75 M dollars in the first year and to 5.6 M dollars annually thereafter. In sensitivity analyses, the conversion of patients from bypass surgery to drug-eluting stents was the largest driver of overall cash flow shifts.

CONCLUSIONS

Although Medicare has proposed to increase reimbursement to ease the impact of drug-eluting stents on hospitals, this increase will not totally offset the costs.

Can we afford to eliminate restenosis?

Over the past decade, coronary stenting has emerged as the dominant form of percutaneous coronary revascularization. However, bare metal stents remain limited by a high incidence of restenosis, leading to frequent repeat revascularization procedures and substantial economic burden. Antiproliferative drug-eluting stents (DES) have recently demonstrated dramatic reductions in rates of restenosis, compared with conventional stenting, but important concerns about their costs have been raised. In this article, we summarize current evidence on the economic impact of restenosis and explore the potential benefits and economic outcomes of DES. In addition to examining the long-term costs of this promising technology, we consider the potential cost-effectiveness of DES from a health care system perspective and the impact of specific patient, lesion, and provider characteristics on these parameters.

Paradigm shifts in cardiovascular medicine

Cardiovascular medicine is changing rapidly with the development, testing, and introduction of new diagnostic and therapeutic methods. New interventional techniques such as the use of drug-eluting stents have important implications for the care of individual patients and the delivery and economics of health care in general. Drug-eluting stents have been shown to improve outcomes among patients undergoing percutaneous coronary intervention by significantly reducing restenosis rates. Two randomized trials have documented that per 100 patients treated with the sirolimus drug-eluting stent, 12.5 to 13.6 patients avoided the need for subsequent target lesion revascularization, when compared with patients treated with conventional stents. The economic effect of the introduction of these stents, which are projected to be two to three times as expensive as conventional stents, is complex and depends on which segment of health care is considered. These stents will be favorably received by patients, physicians, employers, and society as well as payers. However, hospitals may be adversely affected by having increased procedural costs for the stents, along with fewer procedures for evaluation and treatment of restenosis and probably decreased surgical volumes. Drug-eluting stents are only the first of many new technologic advances that will affect cardiovascular care. These procedures have many features in common, including: 1). replacement of major surgical procedures with less invasive approaches; and 2). redistribution of costs, with a decrease in hospital profits but potentially lower costs of health care delivery for society as a whole.

Introduction of stent grafts in the management of patients with a abdominal or thoracic aortic aneurysm: why, perspectives, results

In May 2001 we worked out a system in order to reimburse stentgrafts through the compulsory insurance. An agreement was signed between the different bodies of the NISDI (INAMI/RIZIV) and the association of radiologists and vascular surgeons, specifying the conditions of reimbursement. In this article, I will explain the medical indications as well as the conditions that have to be met by the implanting surgeons. After two years, a first evaluation was made. The figures show some remarkable evolutions. The author therefore has some considerations concerning the procedure.

[Is systematic use of drug-eluting stents justified? Arguments against]

Antiproliferative drug-eluting stents represent a miles tone in advances in interventional cardiology. The amount and quality of the scientific evidence now show these new stents to be highly effective in reducing neointimal proliferation, and hence the process of restenosis. Their clinical impact can be expected to become relevant in terms of both increased indications for angioplasty and the extent of stent usage. However, at this time the systematic use of drug-eluting stents for all patients is not considered justified, because of their limited availability, gaps in our knowledge of their safety, and because their unquestioned clinical benefits have been magnified by exaggerated reports of the clinical problem restenosis represents. Currently, the cost of these stents remains high, and the cost/benefit ratio for certain patients is unfavorable. For these reasons selective use of these new stents is considered more reasonable: they should be used only for those patients who will obtain, in absolute terms, the greatest clinical benefit.

Stenting or stoma creation for patients with inoperable malignant colonic obstructions? Results of a study and cost-effectiveness analysis

BACKGROUND

The aim of the present study was to compare the efficacy, safety, and cost of endoscopic palliative treatment with selfexpanding metallic stents with that of stoma creation in the management of inoperable malignant colonic obstructions.

METHODS

A total of 30 patients with inoperable malignant partial obstruction (due to metastases, hemodynamic instability, or pulmonary instability) in the left colon arising from colorectal or ovarian cancer were included in the study. Fifteen were randomized to undergo palliative metallic colonic stent placement and 15 to undergo stoma creation. The efficacy and safety of the two methods was compared. A cost-effectiveness analysis was also performed, including the cost of postinterventional care.

RESULTS

Stents were placed successfully in 14 of 15 patients. In one patient with obstruction of a tortuous rectosigmoid flexure colon, stenting was not possible; this patient was excluded from the study. During the follow-up period, a moderate, nonocclusive ingrowth of tumor into the stent lumen was observed in six patients; they were all treated with internal laser ablation. The cost-effectiveness analysis showed that although the stoma creation procedure was less expensive, the total difference in average costs for the two methods was 6.9% (132 Euros).

CONCLUSIONS

Self-expanding metallic stent placement is a palliative alternative to colostomy for patients with inoperable malignant colonic strictures. This treatment option provides a better quality of life for the patient, without the psychological repercussions of a colostomy, and it appears to be cost-effective.