Sustained benefit of stenting chronic coronary occlusion: long-term clinical follow-up of the Stenting in Chronic Coronary Occlusion (SICCO) study

Long-term follow-up of therapeutic efficacy of everolimus-eluting bioresorbable vascular scaffold in comparison to everolimus-eluting stent in treatment of chronic total occlusion guided by intracoronary imaging

Background

We hypothesized that 1st generation everolimus-eluting bioresorbable vascular scaffold (BVS) stent associated with less complication and less restenosis rate than everolimus-eluting stent (EES) in chronic total occlusion (CTO) recanalization guided by intracoronary imaging. Therefore, we aimed to assess the safety and performance of BVS stent in CTO revascularization in comparison to EES guided by intracoronary imaging.

Our prospective comparative cross-sectional study was conducted on 60 CTO patients divided into two groups according to type of stent revascularization: group I (EES group): 40 (66.7%) patients and group II (BVS group): 20 (33.3%) patients. All patients were subjected to history taking, electrocardiogram (ECG), echocardiography, laboratory investigation, stress thallium study to assess viability before revascularization. Revascularization of viable CTO lesion guided by intracoronary imaging using optical coherence tomography (OCT). Then, long-term follow-up over 1 year clinically and by multi-slice CT coronary angiography (MSCT). Our clinical and angiographic endpoints were to detect any clinical or angiographic complications during the follow-up period.

Results

At 6 months angiographic follow-up, BVS group had not inferior angiographic parameters but without statistically significant difference (p = 0.566). At 12 months follow-up, there was no difference at end points between the two groups (p = 0.476).

No differences were found at angiographic or clinical follow-up between BVS and EES.

Conclusion

This study shows that 1st generation everolimus-eluting BVS is non-inferior to EES for CTO revascularization. Further studies are needed to clearly state which new smaller footprint BVS, faster reabsorption, magnesium-based less thrombogenicity, and advanced mechanical properties is under development. We cannot dismiss the efficacy and safety of new BVS technology.

Trial registration

ZU-IRB#2498/3-12-2016 Registered 3 December 2016, email: IRB_123@medicine.zu.edu.eg

Three-dimensional visualization of coronary microvasculature in rats with myocardial infarction

BACKGROUND

Assessment of the coronary microcirculation remains challenging.

OBJECTIVE

we explored the feasibility of evaluating the coronary microvasculature in rats with myocardial infarction (MI) using a three-dimensional visualization technique.

METHODS

Animals were divided into the sham operation group (S), MI 45 min group (M45), and MI 180 min group (M180). Opened microvessels were labelled with the fluorescent dye DiI (1, 1'-dioctadecyl-3, 3, 3'3'-tetramethylindo carbocyanine perchlorate) using a heart perfusion method. The microvascular distribution and opening status were observed under laser scanning confocal microscopy, which was adjusted to facilitate evaluation of subjects around 6 to 20 μm.

RESULTS

Microvascular vessels (6-20 μm) were successfully labelled by DiI. Intact and clear three-dimensional microvascular structures were observed in myocardium of sham rats and remote non-infarct myocardial tissue of MI rats, while there was almost no microvascular structure in the infarct area of the M45 group, and only a small amount of microvascular visualization was visualized in the infarct area of the M180 group. The microvascular area and microvascular density in M45 group and M180 group in the infarct border zone were significantly lower than corresponding area in S group.

CONCLUSION

Three-dimensional visualization of opened coronary microvascular vessels is feasible in DiI-labelled myocardium in this rat MI model. This novel technique might be useful for defining the underlying mechanisms of coronary microvascular diseases and observe the efficacy of various therapy strategies on coronary microvessels.

Perioperative management of dual anti-platelet therapy

Dual anti-platelet therapy denotes a regimen of aspirin plus a P2Y₁₂ receptor inhibitor, clopidogrel, prasugrel, or ticagrelor. Such therapy is a cornerstone of medical management following acute coronary syndromes and is imperative following percutaneous coronary interventions. While there is uncertainty about the optimal duration of dual antiplatelet therapy following percutaneous coronary intervention, the new 2016 American College of Cardiology/American Heart Association Guidelines suggest that for patients with stable ischemic heart disease at least six months of such therapy following a drug eluting stent and one month following a bare metal stent should be implemented. In patients with acute coronary syndrome including non-ST elevation and ST elevation myocardial infarction it is recommended to extend dual antiplatelet therapy treatment to one year in both drug eluting stent and bare metal stent groups. There may be latitude for earlier discontinuation in appropriately selected patients; extended dual antiplatelet therapy beyond one year may be beneficial in others. Herein, we describe current guidelines and evidence supporting if and when dual antiplatelet therapy should be interrupted for surgery for patients who have undergone percutaneous coronary intervention.

Coronary Stenting or Balloon Angioplasty for Chronic Total Coronary Occlusions: The Taiwan Experience (A Single-Center Report)

The authors conducted this study to compare the restenosis and reocclusion rates of primary balloon angioplasty alone versus angioplasty followed by stenting in Taiwanese patients with chronic total occlusions. They also evaluated whether stenting reduced the incidence of restenosis and improved left ventricular function in these patients. From October 1998 to April 2000, a total of 294 patients with chronic total occlusion (Thrombolysis in Myocardial Infarction grade 0 flow) underwent recanalization using balloon angioplasty alone or followed by stent implantation. Of these, only 129 patients were included after procedural failure and patients lost to follow-up; 62 patients were placed in the stent group, while 67 patients were assigned to the percutaneous transluminal coronary angioplasty (PTCA) group. Coronary angiography was performed at baseline and at 6 months follow-up or earlier if angina or objective evidence of ischemia involving the target vessel or other vessels was present. Procedural success was 60%. Minimal lumen diameter increased significantly after stenting: 2.97 ±0.41 vs 2.24 ±0.41 (p<0.001); 60% of patients in the stent group were free of restenosis, whereas only 33% in the PTCA group were free of restenosis at follow-up. Only 1 patient in the stent group had reocclusion, as opposed to 17 (25%) patients in the PTCA group (p<0.001). The follow-up minimal lumen diameter (MLD) at 6 months was significantly larger in the stent group: 1.80 ±0.85 mm vs 1.08 ±0.82 mm (p<0.001). Left ventricular function improved in the stent group, but not in the PTCA group (58.44 ±16.58% to 63.60 ±14.59% [p<0.001] vs 54.13 ±15.66% to 54.31 ±15.60% [p=0.885]). More patients had angina in the PTCA group than in the stented group 43 vs 29 (p=0.053). The postprocedural MLD and reference vessel diameter (RVD) were the strong predictors of restenosis and follow-up MLD (p<0.001). Stenting of chronically occluded arteries significantly reduced the incidence of reocclusion and restenosis, at the same time improving left ventricular function in these patients. This should be the procedure of choice after successful angioplasty of chronically occluded vessels.

Restenosis after Percutaneous Coronary Intervention (PCI): Experiences from the Patients' Perspective

BACKGROUND

PCI has been established as an effective treatment for coronary artery disease. Restenosis is a recurrence of a significant narrowing in the treated vessel. Although a part of the investigative and research funding is invested in the prevention and resolving the restenosis problem, little is known about its clinical significance apart from further revascularisation.

AIM

The intention of this study was to clarify the patients perspective of what it means to suffer from documented restenosis after PCI.

METHOD

Patients interviewed had undergone PCI. Data collection and analysis was done simultaneously according to Grounded Theory methodology and continued until new interviews provided no additional information.

RESULTS

"Living with uncertainty" was identified as the core category, and the central focus in the data explains what it means to patients' to suffer from restenosis. The core category was further illuminated in four additional categories labelled "fighting for access to care", "moderating health threats", "trying to understand" and "controlling relatives anxiety".

CONCLUSION

Patients' perceptions of illness and illness-related events, such as symptoms, diagnosis, treatment and prognosis, are considerably affected by uncertainty. This infiltrates their struggle to acquire the care needed, their endeavour to comprehend and moderate health threats, and caring for their family.

Outcome of diabetic and non-diabetic patients undergoing successful coronary angioplasty with bare stent of chronic total occlusion

BACKGROUND

The prognosis of patients with diabetes mellitus and chronic coronary total occlusion (CTO) treated with percutaneous coronary angioplasty (PTCA) is poorly investigated.

METHODS

To compare the long-term outcome of patients with CTO, with and without diabetes mellitus and undergoing successful PTCA with bare stent implantation performed in a single centre, 170 consecutive patients (mean age 62 +/- 10 years) with CTO aged > 1 month were analysed. Death, myocardial infarction, repeat angioplasty and coronary artery by-pass were considered as hard events in 167 patients with available long-term follow-up (mean 25 +/- 15 months).

RESULTS

Vessel mean luminal diameter after the procedure and stent length were 2.5 +/- 0.4 mm and 21.9 +/- 9.4 mm, respectively. No differences were found in baseline clinical, angiographic and procedural variables between the groups, categorized on the basis of presence or absence of diabetes. There were 13 (27%) and 25 (21%) events in diabetic and non-diabetic groups, respectively (P = not significant). Multivariate analysis identified final mean luminal diameter (odds ratio = 4.7192, P = 0.0013) and stent length (odds ratio = 1.0655, P = 0.0003) but not diabetes (P = 0.78) as predictors of events at long-term follow-up.

CONCLUSIONS

Patients with and without diabetes undergoing CTO re-opening with stent implantation do not differ at long-term follow-up in terms of death, myocardial infarction and target lesion revascularizations. Final mean luminal diameter and stent length are significant predictors of events during long-term follow-up.

Clinical effectiveness of bare-metal stenting compared with balloon angioplasty in total coronary occlusions: insights from a systematic overview of randomized trials in light of the drug-eluting stent era

BACKGROUND

We sought to compare, using meta-analytic techniques, bare-metal stent versus balloon angioplasty in the percutaneous treatment of total coronary occlusions by means of a quantitative systematic review and to indicate new avenues for future treatments.

METHODS

MEDLINE and CENTRAL were searched. Inclusion criteria were random allocation, prospective comparison, and intention to treat. Random-effect odds ratios (ORs) with 95% confidence intervals (CIs) for death, myocardial infarction (MI), repeated revascularization, major adverse cardiac events (MACE), and angiographic restenosis and reocclusion were computed.

RESULTS

Nine trials (1409 patients) were included. Death rate was not different in the 2 groups, 0.4% after stenting versus 0.7% after balloon angioplasty (OR 0.72, 95% CI 0.21-2.50). MI rate was significantly increased after stenting (6.7% vs 3.4%, OR 2.06, 95% CI 1.22-3.46), mainly because of a higher rate of periprocedural non-Q-wave MI. By contrast, the risk of repeated revascularization was significantly reduced by stenting (17% vs 32%, OR 0.41, 95% CI 0.31-0.53). This yielded to an overall reduction in the rate of MACE after stenting (23.2% vs 35.4%, OR 0.49, 95% CI 0.36-0.68). Angiographic restenosis and reocclusion were also decreased by stent (41.1% vs 60.9%, OR 0.36, 95% CI 0.23-0.57; 6.8% vs 16%, OR 0.36, 95% CI 0.22-0.59, respectively).

CONCLUSIONS

In total coronary occlusions, stenting yields an important benefit over balloon angioplasty in reduction of MACE, repeated revascularizations, and angiographic restenosis and reocclusion. However, these events remain frequent. Moreover, the finding of an increased rate of periprocedural minor myocardial damage after stenting casts caution. New strategies aimed to reduce the need of repeated revascularizations and periprocedural MIs should be further investigated.

Chronic total occlusion--a definite state?

Successful recanalisation of a chronic coronary occlusion may result in survival advantage. This report describes a 61-year-old man with an initially chronic occluded right coronary artery. A follow-up angiography 2 years later revealed a spontaneous recanalisation.

Predictors for Successful Angioplasty of Chronic Totally Occluded Coronary Arteries

AIMS

Reevaluation of clinical and angiographic predictors for percutaneous recanalization of coronary chronic total occlusion (CTO) using current techniques with conventional PTCA wires and balloons.

METHODS AND RESULTS

We studied 253 consecutive patients with 283 lesions who underwent attempted PTCA of CTO (mean time since occlusion 33 months, range 3-150 month). Immediate procedural success rate was 84.8% (95% CI = 80.3%-88.6%). Multiple clinical and angiographic characteristics were evaluated as possible predictors of success/failure. Multiple logistic regression analysis revealed that a tapered morphology (P < 0.001, OR = 6.1; 95% CI = 2.1-18.2), </=45 degree of angulations of the target artery (P < 0.03, OR = 4.5; 95% CI = 1.2-17.2), length of occlusion <15 mm (P < 0.001, OR = 3.4; 95% CI = 1.6-7.0), and the presence of multiple lesions in the target artery (P < 0.03, OR = 2.2; 95% CI = 1.1-4.4) were statistically significant independent predictors of procedural success. According to absence or presence of the various identified determinants of outcome, predicted procedural success rates varied between 26 and 98%.

CONCLUSIONS

Although the probability of immediate procedural success with percutaneous recanalization of coronary CTO using conventional PTCA is now high, a number of characteristics of the occlusive lesion represent significant modulators of success or failure. These factors should be utilized in the process of patients or lesions selection.

Vascular restenosis - striving for therapy

Restenosis is the limiting entity following coronary angioplasty. It is associated with significant morbidity, mortality and cost, and thus represents a major clinical and economical problem. Despite technical improvements, restenosis after conventional balloon angioplasty occurs in 30 - 60% of cases. Coronary stenting was able to reduce the incidence by approximately 30%; nevertheless, some 250,000 patients experience in-stent restenotic lesions/year worldwide. In-stent restenosis has been recognised as very difficult to manage, with a repeat restenosis rate of 50%, regardless of the angioplasty device used. So far, only vascular brachytherapy has convincingly reduced the incidence of repeat in-stent restenosis (by 50%) and thus, has emerged as the gold standard of therapy. The introduction of drug-eluting stents has shown a great deal of promise for the treatment of both de novo and restenotic lesions, with reported restenosis rates of < 10%, and benefit for virtually all patient subsets at a higher risk of restenosis. This review outlines the pathophysiology, epidemiology and predictors of the restenosis process, and places emphasis on the various treatment options for its prevention and therapy.

Utility of the Safe-Cross-guided radiofrequency total occlusion crossing system in chronic coronary total occlusions (results from the Guided Radio Frequency Energy Ablation of Total Occlusions Registry Study)

The Safe-Cross radiofrequency guidewire (IntraLuminal Therapeutics, Carlsbad, California) combines 3 capabilities: (1) steerability of a conventional 0.014-in intermediate-stiffness guidewire, (2) optical coherence reflectometry to warn the operator when the wire tip approaches within 1 mm of the vessel wall, and (3) delivery of radiofrequency energy pulses to the wire tip to facilitate passage through an occluded segment. The Guided Radio Frequency Energy Ablation of Total Occlusions Registry was a prospective, nonrandomized, multicenter registry that enrolled 116 patients who had long-term coronary total occlusions and in whom a >10-minute good-faith attempt to cross the occlusion using conventional guidewires had failed. The median known duration of occlusion was 22 months (32%; >1 year), and the median length of the occluded segment was 25 mm (25%; >30 mm). Device success was achieved in 63 of 116 of patients (54.3%), and major adverse events occurred in 6.9%, consisting predominantly of isolated increases in cardiac enzymes with no procedure-related deaths, Q-wave myocardial infarctions, or emergency bypass operations. Clinical perforation occurred in 2.6% of patients; of these, perforation in only 1 patient (0.9%) was adjudicated to be directly related to the Safe-Cross radiofrequency wire rather than to the stiff and/or hydrophilic wires used after an inability to advance with the Safe-Cross. Based on these data, the device has been approved in Europe and was recently (January 2004) granted 510K clearance by the Food and Drug Administration.

Coronary stent implantation is superior to balloon angioplasty for chronic coronary occlusions: six-year clinical follow-up of the GISSOC trial

OBJECTIVES

We investigated whether the benefits of stent implantation over balloon percutaneous transluminal coronary angioplasty (PTCA) for treatment of chronic total coronary occlusions (CTO) are maintained in the long term.

BACKGROUND

Several randomized trials have shown that in CTO, stent implantation confers clinical and angiographic mid-term outcomes superior to those observed after PTCA. However, limited information on the long-term results of either technique is available.

METHODS

Six-year clinical follow-up of patients enrolled in the Gruppo Italiano di Studio sullo Stent nelle Occlusioni Coronariche (GISSOC) trial was performed by direct visit or telephone interview. Major adverse cardiac events (MACE), defined as cardiac death, myocardial infarction, target lesion revascularization (TLR), and anginal status, were recorded.

RESULTS

Freedom from MACE at six years was 76.1% in the stent group, compared with 60.4% in the PTCA group (p = 0.0555). This difference was due mainly to TLR-free survival rates (85.1% vs. 65.5% for the stent and PTCA groups, respectively; p = 0.0165). Eleven patients underwent TLR after the nine-month follow-up visit (stent group: n = 5; PTCA group: n = 6); however, in most cases, restenosis of the study occlusion was evident at nine-month angiography.

CONCLUSIONS

This study represents the longest reported clinical follow-up of patients after percutaneous recanalization of CTO and demonstrates that the superiority of stent implantation over balloon PTCA is maintained in the long term. Stent and PTCA results appear to remain stable after nine-month angiographic follow-up. Stent implantation in CTO that can be recanalized percutaneously is therefore a valuable long-term therapeutic option.

Intraluminal blunt microdissection for angioplasty of coronary chronic total occlusions

This study describes a new approach to crossing coronary chronic total occlusions using controlled blunt microdissection and its successful application to coronary angioplasty in three patients. After guidewire techniques failed to cross the occlusions, the blunt intraluminal microdissection catheter was deployed. Actuation of a hinged jaw on the catheter distal assembly created a channel for the guidewire through the diseased segment, in the true lumen (a right coronary and a left circumflex artery) and subintimally (a circumflex artery), to allow angioplasty and stenting. Coronary circulation improved from TIMI grade 0 to 3. Angina was relieved in all three cases. Subsequent angiography for two cases, 2 and 19 months after PTCA, respectively, showed restored flow and patent stented regions.

[Coronary angioplasty in diabetic patients. Current and future perspectives]

It has been estimated that 15-25% of patients who undergo percutaneous or surgical coronary angioplasty are diabetics. The indications for coronary revascularization and initial results of the procedure do not differ substantially between patients with diabetes mellitus and non-diabetics. However, the long-term results of both percutaneous and surgical coronary angioplasty are less favorable in diabetics in terms of mortality and the need for new revascularization procedures. The development and widespread use of stents and glycoprotein IIb/IIIa receptor inhibiting drugs have improved the clinical evolution of diabetics treated with angioplasty. Currently available data show that the administration of glycoprotein IIb/IIIa inhibitors to patients undergoing coronary angioplasty is especially useful in diabetics and improves short-term and long-term results, decreasing one-year mortality by 45%. There seem to be indications for the routine use of glycoprotein IIb/IIIa inhibitors in diabetics treated with angioplasty. While the use of stents has improved long-term and short-term results in diabetics, the success rates of angioplasty in diabetics are still lower than in non-diabetics. Diabetes is still an independent predictor of restenosis and long-term events after stenting interventions. Analysis of the studies comparing percutaneous and surgical revascularization in diabetic patients with multivessel disease shows that surgery is superior in terms of long-term mortality and need for new revascularization procedures. Stenting has improved, but not substantially, the results of multivessel angioplasty in diabetics. Therefore, the indications for angioplasty in multivessel diabetics should be evaluated individually. Factors that contribute to the less favorable post-angioplasty evolution of diabetic patients are more rapid progression of atherosclerosis and, especially, a higher rate of restenosis. New angioplasty techniques, such as brachytherapy and drug-eluting stents, are likely to significantly improve the results of percutaneous interventions in diabetics, thus allowing the indications for angioplasty in diabetics to be extended even further in the near future.

Randomized trial of 90Sr/90Y beta-radiation versus placebo control for treatment of in-stent restenosis

BACKGROUND

After conventional treatment of in-stent restenosis, the incidence of recurrent clinical restenosis may approach 40%. We report the first multicenter, blinded, and randomized trial of intracoronary radiation with the use of a 90Sr/90Y beta-source for the treatment of in-stent restenosis.

METHODS AND RESULTS

After successful catheter-based treatment of in-stent restenosis, 476 patients were randomly assigned to receive an intracoronary catheter containing either 90Sr/90Y (n=244) or placebo (n=232) sources. The prescribed dose 2 mm from the center of the source was 18.4 Gy for vessels between 2.70 and 3.35 mm in diameter and 23.0 Gy for vessels between 3.36 and 4.0 mm. The primary end point, ie, clinically driven target-vessel revascularization by 8 months, was observed in 56 (26.8%) of the patients assigned to placebo and 39 (17.0%) of the patients assigned to radiation (P=0.015). The incidence of the composite including death, myocardial infarction, and target-vessel revascularization was observed in 60 (28.7%) of the patients assigned to placebo and 44 (19.1%) of the patients assigned to radiation (P=0.024). Binary 8-month angiographic restenosis (> or =50% diameter stenosis) within the entire segment treated with radiation was reduced from 45.2% in the placebo-treated patients to 28.8% in the 90Sr/90Y-treated patients (P=0.001). Stent thromboses occurred in 1 patient assigned to placebo <24 hours after the procedure and in 1 patient assigned to 90Sr/90Y at day 244.

CONCLUSIONS

The results of this study demonstrated that beta-radiation using 90Sr/90Y is both safe and effective for preventing recurrence in patients with in-stent restenosis.

Restenosis rates with flexible GFX stents (REFLEX): clinical and angiographic results

The objective of this prospective, multicenter, observational trial was to evaluate the procedural results and longterm outcomes of the flexible AVE GFX coronary stent in native coronary lesions. The trial included 137 consecutive patients (111 [81%] men, age 63.1 +/- 9.2 years) with one vessel disease (n = 76 [55.5%]), two vessel disease (n = 31 [22.6%]), and three vessel disease (n = 30 [21.9%]) with ischemia secondary to a significant denovo lesion (diameter > or = 3 mm, length < or = 18 mm) in a native coronary artery. Stent deployment was successful in 97.8% (134/137) of patients. Angiographic follow-up at 6.1 +/- 1.2 months was available in 111 (82.8%) of 134 patients. All angiographic images were analyzed by an independent core lab. The primary end point was the binary restenosis rate. In-hospital major cardiac events occurred in 3.7%. No postdischarge major adverse cardiac events occurred, except for one abrupt closure (0.7%). Angiographic restenosis was documented in 22 (19.8%) of 111 patients. The GFX stent is easy to handle with high success and low restenosis rates in patients with simple lesions in native coronary arteries and, thus, compares favorably with other sophisticated stents.

Immediate and long-term outcome of recanalization of chronic total coronary occlusions

Eighty-three consecutive patients with 85 coronary total occlusions undergoing coronary angioplasty were retrospectively studied. Patients were divided into two groups according to the occlusion age that was < 30 days (subacute total occlusion [STO]: 25 patients; range 1-30 days) or > 30 days (chronic total occlusion [CTO]: 58 patients; range 3-144 months). All procedures were carried out using a hydrophilic guidewire. Clinical success, consisting of crossing the lesion, balloon dilatation, stent deployment without complications, was 96% in STO and 81% in CTO. Multiple stepwise logistic regression analysis identified a family history of coronary artery disease (CAD), left anterior descending and right coronary artery occlusions as independent predictors of a successful procedure. No major events occurred during or immediately after the angioplasty. After a mean follow-up of 24 +/- 2 months, no difference was found in survival or freedom from myocardial infarction or target vessel revascularization among the STO and CTO patients. Successful recanalization by using a hydrophilic guidewire was achieved in a high percentage of chronic total occlusions with a low incidence of complications and a satisfactory late clinical outcome. Family history of CAD and occlusion of left anterior descending or right coronary arteries are independent predictors of procedural success.

Clinical benefit of small vessel stenting: one-year follow-up of the SISCA trial

OBJECTIVE

To assess the long-term clinical benefit of elective stenting as compared with percutaneous transluminal coronary angioplasty (PTCA) in small coronary arteries.

DESIGN

The Stenting in Small Coronary Arteries (SISCA) trial was a randomized trial comparing elective stenting with PTCA in coronary arteries with a reference diameter of 2.1-3.0 mm. The heparin-coated beStent was used. Control angiography was performed after 6 months, and the patients were followed clinically for 12 months.

RESULTS

At 6 months the clinical outcome was significantly better in the stent group as compared with the PTCA group, with an event-free survival in 90.5 and 76.1% (p = 0.016), respectively. From 6 to 12 months, event-free survival was unchanged in both groups, demonstrating a sustained long-term clinical benefit of elective stenting.

CONCLUSION

Angioplasty in small coronary arteries is associated with a favorable clinical outcome after 1 year. The clinical benefit of elective stenting using the Hepamed-coated beStent is maintained beyond 6 months, without any tendency towards late events. Thus, elective stenting should be considered as an option when treating small coronary arteries.

Microvascular dysfunction in chronic total coronary occlusions

BACKGROUND

Microvascular dysfunction is defined as reduced coronary flow reserve in the absence of an epicardial stenosis. This study determined its prevalence and relation to regional myocardial function in chronic total coronary occlusions (TCO).

METHODS AND RESULTS

After recanalization and stenting of a TCO (duration, >4 weeks) in 42 patients, coronary flow velocity reserve (CFVR) was measured by intracoronary Doppler. In a subset of 27 patients, intracoronary pressure was recorded to obtain the fractional flow reserve (FFR). In 21 patients, the CFVR was reassessed after 24 hours. CFVR was <2.0 in 55% of all patients. In the subgroup with simultaneous pressure recordings, 52% of patients showed a CFVR<2.0 and a FFR>/=0.75, indicating microvascular dysfunction. Both reduced CFVR and reduced FFR occurred in only 2 patients (7.7%). CFVR and FFR were not correlated (r=0.03). A low CFVR was associated with a higher baseline average peak velocity (35.6+/-16.6 versus 22.4+/-11.5 cm/s; P=0.006). Doppler parameters did not change within 24 hours. Regional dysfunction had no influence on CFVR. Patients with diabetes and/or hypertension had a lower CFVR than those without this comorbidity (1.86+/-0.69 versus 2.36+/-0.45; P<0.05).

CONCLUSIONS

Microvascular dysfunction was observed in 55% of TCOs, independent of the impairment of regional myocardial function. Dysfunction was observed more often in patients with diabetes and hypertension. Neither CFVR or FFR alone is appropriate for assessing angioplasty results in patients with a TCO; CFVR should be combined with FFR to differentiate microvascular dysfunction from residual coronary stenosis or diffuse disease.

Randomized comparison of primary stenting and provisional balloon angioplasty guided by flow velocity measurement. Doppler Endpoints Balloon Angioplasty Trial Europe (DEBATE) II Study Group

BACKGROUND

Coronary stenting improves outcomes compared with balloon angioplasty, but it is costly and may have other disadvantages. Limiting stent use to patients with a suboptimal result after angioplasty (provisional angioplasty) may be as effective and less expensive.

METHODS AND RESULTS

To analyze the cost-effectiveness of provisional angioplasty, patients scheduled for single-vessel angioplasty were first randomized to receive primary stenting (97 patients) or balloon angioplasty guided by Doppler flow velocity and angiography (523 patients). Patients in the latter group were further randomized after optimization to either additional stenting or termination of the procedure to further investigate what is "optimal." An optimal result was defined as a flow reserve >2.5 and a diameter stenosis <36%. Bailout stenting was needed in 129 patients (25%) who were randomized to balloon angioplasty, and an optimal result was obtained in 184 of the 523 patients (35%). There was no significant difference in event-free survival at 1 year between primary stenting (86.6%) and provisional angioplasty (85.6%). Costs after 1 year were significantly higher for provisional angioplasty (EUR 6573 versus EUR 5885; P:=0.014). Results after the second randomization showed that stenting was also more effective after optimal balloon angioplasty (1-year event free survival, 93.5% versus 84.1%; P:=0. 066).

CONCLUSIONS

After 1 year of follow-up, provisional angioplasty was more expensive and without clinical benefit. The beneficial value of stenting is not limited to patients with a suboptimal result after balloon angioplasty.

Indications and Problems of Intracranial Stenting Report of Two Cases

There have been few reports of stenting in the intracranial arteries. We used coronary stents in the chronically occluded intracranial vertebral artery and stenosis of internal carotid artery by the external force, and good blood flow were resumed. Stenosis in the intracranial arteries is also a good indication for stent placement when it is due to chronic total occlusion or artery compression by external force. But stent placement in the intracranial arteries has some problems. Stent placement in the intracranial artery is indicated only when the site of stent placement has a diameter of 3 mm or more, is a relatively linear portion of the vertebrobasilar artery or the internal carotid artery proximal to the C3 segment, and does not branch off perforating arteries or is already completely occluded.

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.

Angiographic and clinical outcomes after rescue coronary stenting

The role of coronary stenting in improving outcomes after failed thrombolysis has not been well described. This study represents a registry of rescue coronary interventions performed during a 3 year period in which interventional treatment was changing for this high risk population. We analyzed acute angiographic results and clinical outcomes in 108 consecutive patients treated for thrombolytic failure with either balloon angioplasty (n = 63) or coronary stenting (n = 45). The overall in-hospital mortality rate was 5.5%, and there was no increase in complications in the stent group. Coronary stenting was associated with improved angiographic results including lower residual stenosis in the culprit artery (15 +/- 10% vs. 31 +/- 22%, P < 0.001) without increasing bleeding complications. The rate of in-hospital and long term target vessel revascularization in the stent group was significantly lower than in the unmatched PTCA group. Rescue coronary stenting is safe, improves acute angiographic results compared to PTCA alone and leads to excellent in-hospital and long term outcomes.

Stenting small coronary arteries using two second-generation slotted tube stents: acute and six-month clinical and angiographic results

This prospective study assessed the feasibility, safety, as well as clinical and angiographic outcome after 6 months in 96 patients (100 lesions) treated by stent implantation after a suboptimal balloon angioplasty result in coronary arteries < 3 mm and with a lesion length < 25 mm. The lesions were randomized to treatment with BeStent small or NIR-7. Final quantitative coronary angiography was performed off line. Baseline reference diameter was 2.58 +/- 0.22 mm. Complex lesions constituted 52%, and 23% had unstable angina. Angiographic and procedural success was achieved in 98% and 94%, respectively. At follow-up, 88.5% were free of major adverse cardiac events. The overall restenosis rate was 22.5% (89% angiographic follow-up). There were no statistically significant differences between the stents regarding predefined endpoints. Thus, provisional stent treatment of small coronary arteries using BeStent small or NIR-7 is feasible, safe, and has a favorable clinical and angiographic mid-term outcome.

[The practical clinical guidelines of the Sociedad Española de Cardiología on interventional cardiology: coronary angioplasty and other technics]

Interventional cardiology has had an extraordinary expansion in last years. This clinical guideline is a review of the scientific evidence of the techniques in relation to clinical and anatomic findings. The review includes: 1. Coronary arteriography. 2. Coronary balloon angioplasty. 3. Coronary stents. 4. Other techniques: directional atherectomy, rotational atherectomy, transluminal extraction atherectomy, cutting balloon, laser angioplasty and transmyocardial laser and endovascular radiotherapy. 5. Platelet glycoprotein IIb/IIIa inhibitors. 6. New diagnostic techniques: intravascular ultrasound, coronary angioscopy, Doppler and pressure wire. For the recommendations we have used the classification system: class I, IIa, IIb, III like in the guidelines of the American College of Cardiology and the American Heart Association.

Treatment options for coronary stent restenosis

Treatment of in-stent restenosis with balloon angioplasty alone is adequate for focal lesions but is associated with a 50% recurrence rate for diffuse lesions. For diffuse in-stent restenosis, debulking with atherectomy or laser can significantly reduce the recurrence rate.