Effect of Low-Dose Intracoronary Alteplase During Primary Percutaneous Coronary Intervention on Microvascular Obstruction in Patients With Acute Myocardial Infarction: A Randomized Clinical Trial

IMPORTANCE

Microvascular obstruction commonly affects patients with acute ST-segment elevation myocardial infarction (STEMI) and is associated with adverse outcomes.

OBJECTIVE

To determine whether a therapeutic strategy involving low-dose intracoronary fibrinolytic therapy with alteplase infused early after coronary reperfusion will reduce microvascular obstruction.

DESIGN, SETTING, AND PARTICIPANTS

Between March 17, 2016, and December 21, 2017, 440 patients presenting at 11 hospitals in the United Kingdom within 6 hours of STEMI due to a proximal-mid-vessel occlusion of a major coronary artery were randomized in a 1:1:1 dose-ranging trial design. Patient follow-up to 3 months was completed on April 12, 2018.

INTERVENTIONS

Participants were randomly assigned to treatment with placebo (n = 151), alteplase 10 mg (n = 144), or alteplase 20 mg (n = 145) by manual infusion over 5 to 10 minutes. The intervention was scheduled to occur early during the primary PCI procedure, after reperfusion of the infarct-related coronary artery and before stent implant.

MAIN OUTCOMES AND MEASURES

The primary outcome was the amount of microvascular obstruction (% left ventricular mass) demonstrated by contrast-enhanced cardiac magnetic resonance imaging (MRI) conducted from days 2 through 7 after enrollment. The primary comparison was the alteplase 20-mg group vs the placebo group; if not significant, the alteplase 10-mg group vs the placebo group was considered a secondary analysis.

RESULTS

Recruitment stopped on December 21, 2017, because conditional power for the primary outcome based on a prespecified analysis of the first 267 randomized participants was less than 30% in both treatment groups (futility criterion). Among the 440 patients randomized (mean age, 60.5 years; 15% women), the primary end point was achieved in 396 patients (90%), 17 (3.9%) withdrew, and all others were followed up to 3 months. In the primary analysis, the mean microvascular obstruction did not differ between the 20-mg alteplase and placebo groups (3.5% vs 2.3%; estimated difference, 1.16%; 95% CI, -0.08% to 2.41%; P = .32) nor in the analysis of 10-mg alteplase vs placebo groups (2.6% vs 2.3%; estimated difference, 0.29%; 95% CI, -0.76% to 1.35%; P = .74). Major adverse cardiac events (cardiac death, nonfatal MI, unplanned hospitalization for heart failure) occurred in 15 patients (10.1%) in the placebo group, 18 (12.9%) in the 10-mg alteplase group, and 12 (8.2%) in the 20-mg alteplase group.

CONCLUSIONS AND RELEVANCE

Among patients with acute STEMI presenting within 6 hours of symptoms, adjunctive low-dose intracoronary alteplase given during the primary percutaneous intervention did not reduce microvascular obstruction. The study findings do not support this treatment.

TRIAL REGISTRATION

ClinicalTrials.gov Identifier: NCT02257294.

Nitroglycerin application and coronary arteriogenesis

BACKGROUND

In the presence of a coronary occlusion, pre-existing small collateral vessels (arterioles) develop into much larger arteries (biological bypasses) that have the potential to allow a certain level of perfusion distal to the blockage. Termed arteriogenesis, this phenomenon proceeds via a complex combination of events, with nitric oxide (NO) playing an essential role. The aim of this study was to investigate the effects of supplemental administration of NO donors, i.e., short-acting nitroglycerin (NTG) or slow-release pelleted isosorbide dinitrate (ISDN), on collateral development in a repetitive coronary artery occlusion model in rats.

METHODS

Coronary collateral growth was induced via a repetitive occlusion protocol (ROP) of the left anterior descending coronary artery (LAD) in rats. The primary endpoints were the histological evaluation of rat heart infarct size and ST-segment elevation (ECG-analysis) upon final permanent occlusion of the LAD (experimentally induced myocardial infarction). The effects of NTG or ISDN were also evaluated by administration during 5 days of ROP. We additionally investigated whether concomitant application of NTG can compensate for the anti-arteriogenic effect of acetylsalicylic acid (ASA).

RESULTS

After 5 days of ROP, the mean infarct size and degree of ST-elevation were only slightly lower than those of the SHAM group; however, after 10 days of the protocol, the ROP group displayed significantly less severe infarct damage, indicating enhanced arteriogenesis. Intermittent NTG application greatly decreased the ST-elevation and infarct size. The ISDN also had a positive effect on arteriogenesis, but not to the same extent as the NTG. Administration of ASA increased the infarct severity; however, concomitant dosing with NTG somewhat attenuated this effect.

CONCLUSION

Intermittent treatment with the short-acting NTG decreased the size of an experimentally induced myocardial infarct by promoting coronary collateral development. These new insights are of great relevance for future clinical strategies for the treatment of occlusive vascular diseases.

Use of sodium nitroprusside in retrograde percutaneous coronary intervention for chronic total occlusion: A case report

RATIONALE

Chronic total occlusion continues to be a challenging lesion subset for percutaneous coronary intervention.

PATIENT CONCERNS

A 65-year-old male patient was admitted with symptoms of angina pectoris for 9 months.

DIAGNOSES

Coronary angiography showed a severe stenosis in the proximal left anterior descending artery and a chronic total occlusion (CTO) in the proximal right coronary artery. The complexity of the CTO was stratified using the J-CTO score and the PROGRESS CTO score.

INTERVENTIONS

Antegrade wire escalation for CTO of RCA failed. The septal collaterals to RCA were initially judged to be poor and not suitable for intervention.

OUTCOMES

However, administration of sodium nitroprusside improved collateral flow and enabled the identification of retrograde channels suitable for wire crossing and successful retrograde PCI.

LESSIONS

The study showed that faintly visible to even invisible septal collateral connections can be crossed with the septal "trial and error" surfing technique after the administration of sodium nitroprusside.

Long-term Survival Benefit of Statin in Patients with Coronary Chronic Total Occlusion without Revascularization

BACKGROUND

Limited data are available on the efficacy of statin therapy in stable ischemic heart disease with chronic total occlusion (CTO) without revascularization. We investigated whether statin therapy could be beneficial in stable patients with CTO without revascularization.

METHODS

From March 2003 to February 2012, 2,024 patients with at least one CTO were enrolled in a retrospective, single-center registry; 664 of these patients were managed conservatively without an initial revascularization strategy. Among them, we excluded CTO cases involving acute coronary syndrome, in-hospital death or incomplete data and classified 551 patients into statin (n = 369) and non-statin (n = 182) groups according to use of statin at discharge. Propensity score matching analysis was also performed in 148 pairs. The primary outcome was cardiac death.

RESULTS

The median overall follow-up duration was 45.7 months (interquartile range: 19.9-70.5 months). Cardiac death occurred in 22 patients (6.0%) in the statin group vs. 24 patients (13.2%) in the non-statin group (P < 0.001). In propensity score matching analysis, statin therapy was associated with a low risk of cardiac death (adjusted hazard ratio [HR], 0.39; 95% confidence interval [CI], 0.18-0.85; P = 0.022) and major adverse cardiac events (adjusted HR, 0.66; 95% CI, 0.43-0.98; P = 0.043). On multivariate analysis, independent predictors for cardiac death were age > 70 years, renal insufficiency, prior myocardial infarction, left ventricular ejection fraction < 40%, proximal-to-mid CTO location, and no use of statin in CTO patients.

CONCLUSION

Statin therapy at discharge may be associated with a reduction in long-term cardiac mortality in stable CTO patients without revascularization.

[A Case of Takayasu Arteritis with Acute Bilateral Occlusion of the Internal Carotid Arteries]

A 38-year-old woman developed disturbance of consciousness and quadriplegia. Magnetic resonance images showed scattered acute infarcts in both hemispheres and bilateral occlusion of the intracranial artery (ICA). Immediate mechanical thrombectomy restored the patency of the ICA. Contrast-enhanced computed tomography revealed bilateral wall thickening of the abdominal aorta and the iliac arteries. This finding and an elevated erythrocyte sedimentation rate supported the diagnosis of Takayasu arteritis. Here, we thus report a rare case of Takayasu arteritis with acute bilateral occlusion of the internal carotid arteries.

Opening of calcium-activated potassium channels improves long-term left-ventricular function after coronary artery occlusion in mice

BACKGROUND

Opening of mitochondrial calcium-activated potassium channels (BK_Ca) reduces infarct size after myocardial ischemia/reperfusion injury (I/R). It is unknown if targeting BK_Ca-channels improves cardiac performance in the long-term after I/R.

METHODS

Experiments were conducted in compliance with institutional and national guidelines in C57BL/6 mice (n=7-8/group). Animals were randomized into two groups. Preconditioning was induced by intraperitoneal application of NS1619 (NS, 1μg/g bw) 10min before ischemia, control animals (Con) received the vehicle. All animals underwent 45min of myocardial ischemia and four weeks of reperfusion. Transthoracal Echocardiography (TTE) was conducted one and four weeks after ischemia (TTEW1/TTEW4) and additionally a cardiac MRI was done in week four. At the end of experiments the infarction scar was determined by AZAN staining.

RESULTS

TTE revealed that NS1619 improved ejection fraction one week (Con: 36±4%, NS: 45±4%; P<0.05) and four weeks after I/R (Con: 33±11%, NS: 46±8%; P<0.05). Preconditioning with NS1619 reduced end-diastolic volume at both time points (TTEW1: Con: 60±12μl, NS: 45±8μl; TTEW4: Con: 82±31μl, NS: 44±8μl; each P<0.05) and increased fractional shortening after four weeks (TTEW4: Con: 12±6%, NS: 24±8%; P<0.05). MRI-analysis after four weeks confirmed the echocardiographic results. NS1619 increased ejection fraction by 45% (MRI: Con: 29±6%, NS: 42±9%; P<0.05 vs. Con) and reduced end-diastolic and -systolic volume (EDV, ESV) compared to control (MRI: EDV: Con: 110±19μl, NS: 88±16μl; ESV: Con: 79±19μl, NS: 53±18μl; each P<0.05). Preconditioning reduced infarction scar after four weeks by 25% (Con: 12±3%, NS: 9±2%; P<0.05).

CONCLUSIONS

Preconditioning by opening of BK_Ca-channels with NS1619 improves cardiac performance after four weeks of reperfusion and reduces myocardial infarction scar.

Association of β-blocker therapy with long-term clinical outcomes in patients with coronary chronic total occlusion

There are limited data regarding the efficacy of β-blockers for secondary prevention in patients with coronary chronic total occlusion (CTO). Therefore, we investigated the association of β-blocker therapy with long-term clinical outcomes in CTO patients. From March 2003 to February 2012, a total of 2024 CTO patients treated with either medical therapy alone or revascularization were enrolled in the study. We assessed 1596 patients with stable ischemic heart disease and divided them into the β-blocker group (n = 932) and the no-β-blocker group (n = 664). The primary outcome was all-cause death. The median follow-up duration was 3.9 (interquartile range: 2.0-6.2) years. All-cause death occurred in 11.6% patients in the β-blocker group and 13.6% patients in the no-β-blocker group (hazard ratio [HR]: 0.81, 95% confidence interval [CI]: 0.61-1.08; P = 0.15). In the propensity score-matched population (570 pairs), all-cause death occurred in 12.3% patients in the β-blocker group and 12.8% patients in the no-β-blocker group (HR: 0.93, 95% CI: 0.67-1.29; P = 0.66). In subgroup analysis, β-blocker therapy was associated with better outcome, in terms of all-cause death, in patients with CTO of the left anterior descending coronary artery and Synergy Between PCI with Taxus and Cardiac Surgery (SYNTAX) score ≥23 (P for interaction = 0.01 and 0.02, respectively). In conclusion, β-blocker therapy was not associated with favorable long-term clinical outcomes in stable CTO patients, regardless of treatment strategy. However, β-blocker therapy might be beneficial in a highly selective group of CTO patients with a high ischemic burden.

First-Generation Versus Second-Generation Drug-Eluting Stents in Coronary Chronic Total Occlusions: Two-Year Results of a Multicenter Registry

BACKGROUND

Limited data are available regarding the long-term clinical outcomes of second-generation drug-eluting stents (DES) versus first-generation DES in patients with coronary chronic total occlusion (CTO) who undergo percutaneous coronary intervention (PCI). The aim of this study was to compare the clinical outcomes of second-generation DES with those of first-generation DES for the treatment of CTO.

METHODS AND RESULTS

Between March 2003 and February 2012, 1,006 consecutive patients with CTO who underwent successful PCI using either first-generation DES (n = 557) or second-generation DES (n = 449) were enrolled in a multicenter, observational registry. Propensity-score matching was also performed. The primary outcome was cardiac death over a 2-year follow-up period. No significant differences were observed between the two groups regarding the incidence of cardiac death (first-generation DES versus second-generation DES; 2.5% vs 2.0%; hazard ratio [HR]: 0.86; 95% confidence interval [CI]: 0.37 to 1.98; p = 0.72) or major adverse cardiac events (MACE, 11.8% vs 11.4%; HR: 1.00; 95% CI: 0.67 to 1.50; p = 0.99). After propensity score matching, the incidences of cardiac death (HR: 0.86; 95% CI: 0.35 to 2.06; p = 0.86) and MACE (HR: 0.93; 95% CI: 0.63 to 1.37; p = 0.71) were still similar in both groups. Furthermore, no significant differences were observed between sirolimus-eluting, paclitaxel-eluting, zotarolimus-eluting, and everolimus-eluting stents regarding the incidence of cardiac death or MACE.

CONCLUSION

This study shows that the efficacy of second-generation DES is comparable to that of first-generation DES for treatment of CTO over 2 years of follow-up.

Impact of Neutrophil to Lymphocyte Ratio (NLR) Index and Its Periprocedural Change (NLRΔ) for Percutaneous Coronary Intervention in Patients With Chronic Total Occlusion

We assessed the association between neutrophil to lymphocyte ratio (NLR) and chronic coronary total occlusion (CTO), as well as clinical prognosis of percutaneous coronary intervention (PCI). Patients referred for elective coronary angiography for stable angina pectoris were enrolled, including a CTO (n = 160) and a non-CTO group (n = 160). Neutrophil to lymphocyte ratio on admission and post-PCI was measured, and NLR_Δ was defined as the change between the 2 values. Subgroup analysis was performed based on the value of NLR_Δ (≥0.5 vs <0.5). Clinical characteristics, angiographic data, and follow-up data were recorded. Compared with the non-CTO group, the total white blood cell count, neutrophil counts, and NLR were significantly higher in the CTO group. In the NLR_Δ ≥ 0.5 subgroup, the incidence of severe dissection, slow coronary flow, in-stent restenosis (ISR), and major adverse cardiac events (MACEs) was obviously higher. In multivariate analysis, NLR_Δ was independently and positively associated with higher risks of ISR and MACE. The NLR could be a potential predictor of CTO, and NLR_Δ is independently associated with the adverse clinical outcomes in patients who underwent PCI.

Effect of Pioglitazone in Preventing In-Stent Restenosis after Percutaneous Coronary Intervention in Patients with Type 2 Diabetes: A Meta-Analysis

Background

The benefits of pioglitazone in patients with type 2 diabetes mellitus (T2DM) after percutaneous coronary intervention (PCI) is unclear.

Objectives

To evaluate the effect of pioglitazone on prevention of in-stent restenosis (ISR) in patients with T2DM after PCI.

Methods

All full-text published relevant studies compared the effect of pioglitazone with control group (placebo or no pioglitazone treatment) on ISR in patients with T2DM after PCI were identified by searching the databases including PubMed, EMBASE, Cochrane Library and ISI Web of Science through October 2015. The endpoints were defined as the rate of ISR, late lumen loss, in-stent neointimal volume, target lesion revascularization (TLR) and major adverse cardiac events (MACE).

Results

Six studies (5 RCTs and 1 retrospective study), comprising 503 patients, were included into this meta-analysis. In the pioglitazone group, as compared with the control group, the risk ratio for ISR was 0.48 (I² = 14.5%, P = 0.322; 95%CI 0.35 to 0.68, P<0.001), the risk ratio for TLR was 0.58 (I² = 6.0%, P = 0.363; 95%CI 0.38 to 0.87, P = 0.009). The result showed there was no association between the use of pioglitazone and the events of MACE (I² = 36.7%, P = 0.209; RR 0.56, 95%CI 0.30 to 1.05, P = 0.071). For the considerable heterogeneity, further analysis was not suitable for the endpoints of late lumen loss (I² = 81.9%, P<0.001) and neointimal volume (I² = 75.9%, P = 0.016).

Conclusions

The treatment of pioglitazone was associated with a reduction in ISR and TLR in T2DM patients suffering from PCI, except the incidence of MACE.

Drug-eluting stent thrombosis in the treatment of chronic total coronary occlusions: incidence, presentation and related factors. Data from the CIBELES trial

INTRODUCTION AND OBJECTIVES

The aim of this study was to analyze the incidence of drug-eluting stent thrombosis (sirolimus or everolimus) in patients with chronic total coronary occlusions (CTO) and to determine its clinical implications and related factors.

METHODS

Data from the 12-month follow-up of the 207 patients included in the CIBELES trial with CTO were analyzed.

RESULTS

Stent thrombosis occurred in three patients, two definite and one probable (overall thrombosis rate: 1.4%). However, there were no cases of death or Q-wave myocardial infarction. In univariate analysis, patients with a higher incidence of stent thrombosis were those in whom the target vessel was the left anterior descending, who had single-vessel disease, were assigned to treatment with sirolimus-eluting stents, and those with smaller minimum luminal diameter immediately after the procedure. In multivariate analysis, the only independent predictor of stent thrombosis was minimal luminal diameter immediately after the procedure.

CONCLUSIONS

The rate of drug-eluting stent thrombosis in patients with CTO is relatively low (1.4%). The only independent predictor of stent thrombosis in this context was minimal luminal diameter after the procedure and the clinical presentation was in all cases relatively benign.

Third-generation zotarolimus-eluting and everolimus-eluting stents in all-comer patients requiring a percutaneous coronary intervention (DUTCH PEERS): a randomised, single-blind, multicentre, non-inferiority trial

BACKGROUND

Third-generation, permanent-polymer-based drug-eluting stents with novel, flexible designs might be more easily delivered than previous generations of stents in complex coronary lesions, but might be less longitudinally stable. We aimed to assess the safety and efficacy in all-comer patients of two third-generation stents that are often used clinically, but that have not yet been compared, and one of which has not previously been assessed in a randomised trial.

METHODS

In this investigator-initiated, single-blind, multicentre, randomised, two-arm, non-inferiority trial, patients aged 18 years and older who required a percutaneous coronary intervention with implantation of a drug-eluting stent were recruited from four study sites in the Netherlands. We randomly assigned patients by independently managed computer-generated allocation sequences in a 1:1 ratio to receive either cobalt-chromium-based zotarolimus-eluting stents (Resolute Integrity, Medtronic, Santa Rosa, CA, USA) or platinum-chromium-based everolimus-eluting stents (Promus Element, Boston Scientific, Natick, MA, USA). Patients and analysts were masked to the allocated stent, but treating clinicians were not. The primary endpoint of target-vessel failure was a composite of safety (cardiac death or target-vessel-related myocardial infarction) and efficacy (target-vessel revascularisation) at 12 months, analysed by intention to treat (with a non-inferiority margin of 3·6%). This trial is registered with ClinicalTrials.gov, number NCT01331707.

FINDINGS

Between Nov 25, 2010, and May 24, 2012, 1811 eligible all-comer patients, with 2371 target lesions, were enrolled in the study. 370 (20%) patients presented with ST-elevation myocardial infarction and 447 (25%) with non-ST-elevation myocardial infarction. 906 patients were assigned to receive zotarolimus-eluting stents and 905 to receive everolimus-eluting stents. Ease of stent delivery was shown by very low numbers of patients requiring treatment other than their assigned study treatment (six [1%] in the zotarolimus-eluting stent group vs five [1%] in the everolimus-eluting stent group; p=0·22). 12-month follow-up results were available for 1810 patients (one patient in the zotarolimus-eluting stent group withdrew consent). The primary endpoint was met by 55 (6%) of 905 patients in the zotarolimus-eluting stent group and 47 (5%) of 905 in the everolimus-eluting stent group. The zotarolimus-eluting stent was non-inferior to the everolimus-eluting stent (absolute risk difference 0·88%, 95% CI -1·24% to 3·01%; upper limit of one-sided 95% CI 2·69%; non-inferiority p=0·006). We noted no significant between-group differences in individual components of the primary endpoint. Definite stent thrombosis occurred in three (0·3%) patients in the zotarolimus-eluting stent group and six (0·7%) patients in the everolimus-eluting stent group (p=0·34). Longitudinal stent deformation was seen only in the everolimus-eluting stent group (nine [1·0%] of 905 vs 0 of 906, p=0·002; nine of 1591 [0·6%] everolimus-eluting stents implanted became deformed), but was not associated with any adverse events.

INTERPRETATION

Both stents were similarly efficacious and safe, and provided excellent clinical outcomes, especially in view of the large number of patients who presented with acute myocardial infarctions.

FUNDING

Boston Scientific, Medtronic.

[Effects of pretreatment with metoprolol on cardiomyocyte apoptosis and caspase-8 activation after coronary microembolization in rats]

OBJECTIVE

To investigate the effects of metoprolol on cardiomyocyte apoptosis and caspase-8 activation after coronary microembolization(CME) in rats.

METHODS

Adult rats were randomly assigned into CME group (intraventricular injection of 3000 microspheres with 42 µm in diameter), sham-operated group (0.1 ml saline) and CME plus metoprolol group (pretreatment with 3 bolus metoprolol 2.5 mg/kg intravenous injection at 10 minutes interval at 30 minutes before microspheres injection, n = 15, each group). Cardiac function was evaluated by echocardiography at 6 hours post various treatments. Cardiomyocyte apoptosis was detected with TUNEL staining and the expression of caspase-3 and caspase-8 was detected with Western blot analysis.

RESULTS

Compared with sham-operated group, LVEF (72.68% ± 3.26% vs. 82.64% ± 3.43%, P < 0.05), fractional shortening (FS) (37.46% ± 2.38% vs. 42.85% ± 3.25%) and cardiac output (CO) [(0.101 ± 0.006) L/min vs. (0.162 ± 0.008) L/min] were significantly reduced while left ventricular end-diastolic diameter (LVEDd) [(6.22 ± 0.17) mm vs. (5.18 ± 0.43) mm] was significantly increased in CME group (all P < 0.05). Cardiac function [LVEF:73.94% ± 4.22%, FS:38.53% ± 2.03%, CO:(0.120 ± 0.012) L/min, LVEDd:(6.18 ± 0.27) mm] was similar in CME plus metoprolol group compared to CME group (all P > 0.05). The cardiomyocytes apoptosis rates (3.19% ± 1.23% vs. 0.18% ± 0.10%) and the levels of activated caspase-3 and caspase-8 proteins were significantly increased in CME group than in sham-operated group (all P < 0.05). The cardiomyocyte apoptosis rate (1.32% ± 0.28%) and the levels of activated caspase-3 and caspase-8 proteins were significantly lower in CME plus metoprolol group than in CME group (all P < 0.05).

CONCLUSIONS

Metoprolol pretreatment reduced post-CME myocardial apoptosis possibly through downregulating death receptor-mediated apoptotic pathway.

G-CSF induced arteriogenesis in humans: molecular insights into a randomized controlled trial

AIMS

Recent data have demonstrated the feasibility of therapeutic induction of coronary collateral growth (arteriogenesis); however, mechanisms of action of such therapeutic collateral stimulation in humans are unknown. The aim of this study was to evaluate potential mechanisms, especially the involvement of arteriogenesis-relevant genes.

METHODS AND RESULTS

A total of 52 patients were randomized into two groups: subcutaneous G-CSF (10 μg/kg; n=26) or placebo (n=26). Before and after this 2-week treatment, collateral-flow index (CFI) was determined by simultaneous measurement of mean aortic, distal coronary occlusive and central venous pressure. CD34+ endothelial progenitor cells (EPC) and monocytes were quantified before, during and after treatment; gene-expression analysis of monocytes was performed with real-time polymerase chain reaction (RT-PCR). G-CSF lead to a significant increase of EPC and monocytes (4.8 and 2.6 fold, p < 0.05); for both cell types, the extent of increase correlated with CFI increase (r=0.23 and 0.14, p < 0.05). G-CSF also induced a change in gene expression of pro-and anti-arteriogenic genes in monocytes. Among nine assessed genes, three were found to be differentially regulated (IL8, JAK2, and PNPLa4; p < 0.05).

CONCLUSIONS

The mechanism of induction of collateral growth by G-CSF is related to an increase of EPC and of peripheral monocytes. It also leads to a change toward a pro-arteriogenic gene expression in peripheral monocytes.

Five-year outcomes in patients with chronic total coronary occlusion treated with drug-eluting vs bare-metal stents: a case-control study

BACKGROUND

Limited data exist on long-term safety and effectiveness of drug-eluting stents (DESs) in true chronic total coronary occlusion (CTO) settings. We evaluated 5-year clinical outcomes of patients with CTO treated successfully with DES vs bare-metal stent (BMS).

METHODS

We compared the 5-year clinical outcomes of 156 patients treated with DES implantation with outcomes of a historical cohort of 159 patients treated with BMS. Primary end point was freedom from major adverse cardiac events (MACEs; defined as death, myocardial infarction [MI], and target lesion revascularization [TLR]); secondary end points were freedom from target vessel failure (TVF; combination of target vessel revascularization, MI, and cardiac death) and TLR at 5 years.

RESULTS

After 5 years, the DES group had significantly superior event-free survival from MACE (84% vs 69%; log rank P < 0.001), TVF (71% vs 84%; P = 0.002), and TLR (77% vs 92%; P = 0.0001), compared with the BMS group. The Cox proportional hazards model identified BMS vs DES (adjusted hazard ratio [HR] = 3.37; 95% confidence interval [CI], 1.85-6.17; P = 0.001), final minimal lumen diameter (HR, 0.27; 95% CI, 0.14-0.52; P = 0.0001), and stent length (HR, 1.01; 95% CI, 1.00-1.03; P = 0.03) as independent predictors of MACE at 5-year follow-up. Twelve (7%) and 7 (4%) stent thromboses occurred in the DES and BMS groups (P = 0.23), respectively.

CONCLUSIONS

After 5 years, DESs were superior to BMSs in reducing MACE, TVF, and TLR in patients with CTO and should be the preferred strategy.

[The incidence of postoperative myocardial infarction and the left ventricular function in patients with type 2 diabetes mellitus after recanalization of chronic coronary occlusions]

AIM

To study the effects of intracoronary administration of the ischemic preconditioning (IP) trigger adenosine on the reduced incidence of percutaneous coronary intervention (PCI)-associated myocardial infarction (MI) and left ventricular (LV) systolic and contractile function in patients with type 2 diabetes mellitus (DM) during recanalization of chronic coronary occlusions (CCO).

SUBJECTS AND METHODS

The patients were divided into 4 groups: 1) 45 patients without DM who received intracoronary placebo infusion; 2) 51 patients without DM who had 10 mg intracoronary adenosine during PCI; 3) 34 patients with type 2 DM who had intracoronary adenosine during PCI; 4) 37 with type 2 DM who received intracoronary placebo. Troponin I and the MB fraction of creatine phosphokinase were measured an hour before and 18-24 hours and 5 days after PCI. The authors estimated the incidence of PCI-associated MI according to the ESC/ACCF/AHA/WHF (2007) criteria and the time course of changes in LV ejection fraction (EF) and end-systolic volume (ESV) and end-diastolic volume, impaired LV local contractility index (ILVLCI) in 167 patients with CCO 1 day and 1 and 12 months after PCI.

RESULTS

There was an improvement in myocardial systolic and contractile function after recanalization and stenting for CCO. The intracoronary adenosine groups showed significantly reduced incidence of PCI-associated MI, increased LV EF, and decreased LV ESV and ILVLCI as compared to the placebo groups.

CONCLUSION

The intracoronary injection of the IP trigger adenosine is an effective and safe method to improve LV systolic and contractile function in patients with CCO and type 2 DM.

[Resveratrol improves coronary collateral circulation in pigs with experimental acute coronary occlusion]

OBJECTIVE

To evaluate the impact of resveratrol on coronary collateral circulation in pigs suffered from experimental acute coronary occlusion.

METHODS

Eighteen healthy pigs were randomly divided into 3 groups: resveratrol group, nitroglycerin group and control group. Animal model of acute coronary occlusion was established through PTCA method, and the blood flow spectrum in the left circumflex artery (LCX) was detected using intracoronary Doppler ultrasound.

RESULTS

The average peak velocity (APV) in infarction correlation artery (IRA) was significantly decreased immediately after coronary occlusion [(0.85 ± 0.25) cm/s vs. (24.83 ± 3.43) cm/s, P < 0.05]. The APV remained unchanged during 0, 30 and 60 minutes after the occlusion. Reversed or bidirectional blood flow was observed and the APV increased significantly [(9.22 ± 0.80) cm/s vs. (0.84 ± 0.21) cm/s, (8.93 ± 1.28) cm/s vs. (0.86 ± 0.26) cm/s respectively, P < 0.05] after the coronary injection of resveratrol (2 mg) or nitroglycerin (0.3 mg). There was no significant difference in peak APV between the resveratrol and nitroglycerin groups. The duration of increased APV was significantly longer in resveratrol group than that in nitroglycerin group [(58.83 ± 6.15) min vs. (21.80 ± 5.79) min, P < 0.05].

CONCLUSIONS

The collateral circulation after acute coronary occlusion was obviously insufficient in pigs. Resveratrol could significantly improve the blood flow in coronary collateral circulation after acute occlusion in this model.

[Effect of erythropoietin on reperfusion arrhythmias in rats]

OBJECTIVE

To explore the effect of erythropoietin (EPO) on reperfusion arrhythmias in rats and identify the possible mechanism involved.

METHODS

Forty-five SD rats were randomized into a sham-operated group and 4 cardiac ischemia/reperfusion (IR) injury groups, which were further divided into IR group, LY294002 group, EPO group, and EPO+LY294002 group. Cardiac IR injury was induced in the 4 IR injury groups by ligating the left anterior descending branch of the coronary artery (LAD) for 30 min followed by reperfusion for 3 h, with subsequent treatments accordingly. The occurrence of arrhythmias was monitored and scored during experiment, and the levels of serum CK-MB and cTnI were detected. The content of MDA in the myocardium was determined by thiobarbituric acid (TBA) method, and the content of SOD by xanthine oxidase method.

RESULTS

The arrhythmia score in EPO group was significantly lower than those in IR, LY294002 and EPO+ LY294002 groups (P<0.05). The levels of serum CK-MB and cTnI were significantly lower in EPO group than in the other 3 IR groups (P<0.001). The EPO group showed also significantly lower MDA content (P<0.001) and higher SOD content than the other 3 IR groups (P<0.001).

CONCLUSION

EPO at the dose of 1000 mg/kg decreases the incidence of reperfusion arrhythmias in rats, and this effect can be attenuated by LY294002 pretreatment, suggesting that the cardioprotective effect of EPO involves antioxidation mediated by the phosphoinositide 3-kinase (PI3K) pathway.

[Significance of percutaneous transluminal coronary intervention for chronic total occlusions assessed as non-viable by myocardial scintigraphy]

OBJECTIVES

The effectiveness of percutaneous transluminal coronary intervention (PCI) was evaluated for chronic total occlusion (CTO) assessed as non-viable by myocardial scintigraphy.

METHODS

In the period from January 2003 to October 2006, 17 patients who had successful reopening of the artery through revascularization by PCI for CTO assessed as non-viable were classified as the P group, and 30 patients whose course was observed while undergoing medical therapy after being assessed as nonviable formed the M group. Left ventricular ejection fraction (LVEF), left ventricular end-diastolic volume (LVEDV) and SD/chord were measured in both groups before the procedure and at the chronic phase (mean 6.2 months). The incidences of chronic cardiac events at mean 20.5 months were compared.

RESULTS

No significant differences were revealed between the two groups in LVEF and LVEDV prior to the procedure. No significant differences between the groups were revealed for Delta LVEF or Delta LVEDV. A significant improvement (p < 0.05) was revealed for SD/chord in the P group with - 1.50 +/- 0.25 before the procedure, becoming - 1.34 +/- 0.33 in the chronic phase, but the M group revealed no significant change. No significant difference was revealed in the avoidance of chronic cardiac events with 94.1% for the P group and 86.0% for the M group.

CONCLUSIONS

Improvement in local left ventricular wall motion by revascularization is possible even in patients with chronic total occlusions assessed as non-viable by myocardium scintigraphy.

[Comparison between bare metal stents and drug eluting stents for the treatment of chronic total occlusion]

Patients with chronic total occlusions (CTO) are under high risk of restenosis, repeat recanalization procedures and mortality after stent. In our study we evaluated the clinical and angiographic efficacy of bare metal stents (BMS) and drug eluting stents (DES) implantation for chronic total occlusion.107 patients were divided into two groups: who were successfully treated with BMS (n=60) 56,1% and those who had CTO lesions with Cypher implantation(n=47) 43,9%. Six-month angiographic restenosis rates and major adverse cardiac events (MACE) were compared between the groups. At 6-month angiographic follow up, the restenosis rate was significantly higher in the BMS group (21,8% vs. 4,7%; p<0,001), but there was no significant statistic difference in the rate of MACE (11,6% vs.13,3%; p>0,05). Therefore, the implantation of DES in the treatment of CTO lesions showed more favourable results regarding restenosis compared with BMS implantation, but there was not a trend towards lower MACE rates.