Incidence and predictors of target vessel revascularization following percutaneous transluminal coronary angioplasty: a report from the National Heart, Lung, and Blood Institute Percutaneous Transluminal Coronary Angioplasty Registry

A nano-bioconjugate modified with anti-SIRPα antibodies and antisense oligonucleotides of mTOR for anti-atherosclerosis therapy

Atherosclerosis is the main cause of a series of fatal cardiovascular diseases, characterized by pathological accumulation of apoptotic cells and lipids. Pro-phagocytic antibody-based or pro-autophagy gene-based therapies are currently being explored to stimulate the phagocytic clearance of apoptotic cells and lipid metabolism; however, monotherapies are only moderately effective or require high doses with unacceptable side effects. Herein, we engineered a specific nano-bioconjugate loaded with antisense oligonucleotides (ASOs) of mammalian target of rapamycin (mTOR) and modified with anti-signal-regulated protein-α antibody (aSIRPα) for macrophage-mediated atherosclerosis therapy. The specific nano-bioconjugate utilized acid-responsive calcium phosphate (CaP) as a carrier to load mTOR ASOs, coated with lipid on the surface of CaP nanoparticles (ASOs@CaP), and subsequently modified with aSIRPα. The resulting nano-bioconjugates could accumulate within atherosclerotic plaques, target to macrophages and reactivate lesional phagocytosis through blocking the CD47-SIRPα signaling axis. In addition, efficient delivery of mTOR ASOs inhibited mTOR expression, which significantly restored impaired autophagy. The combined action of mTOR ASOs and aSIRPα reduced apoptotic cells and lipids accumulation. This nanotherapy significantly reduced plaque burden and inhibited progression of atherosclerotic lesions. These results show the potential of specific nano-bioconjugates for the prevention of atherosclerotic cardiovascular disease. STATEMENT OF SIGNIFICANCE: Atherosclerosis is the main cause of a series of fatal cardiovascular diseases. Pro-phagocytic antibody-based or pro-autophagy gene-based therapies are currently being explored to stimulate the phagocytic clearance of apoptotic cells and lipid metabolism; however, monotherapies are only moderately effective or require high doses with unacceptable side effects. Herein, we engineered a specific nano-bioconjugate loaded with antisense oligonucleotides (ASOs) of mammalian target of rapamycin (mTOR) and modified with anti-signal-regulated protein-α antibody (aSIRPα) for macrophage-mediated atherosclerosis therapy. Our study demonstrated that the combined action of mTOR ASOs and aSIRPα reduced apoptotic cells and lipids accumulation. This nanotherapy significantly reduced plaque burden and inhibited progression of atherosclerotic lesions. These results show the potential of specific nano-bioconjugates for the prevention of atherosclerotic cardiovascular disease.

Platelet Membrane-Coated Nanocarriers Targeting Plaques to Deliver Anti-CD47 Antibody for Atherosclerotic Therapy

Atherosclerosis, the principle cause of cardiovascular disease (CVD) worldwide, is mainly characterized by the pathological accumulation of diseased vascular cells and apoptotic cellular debris. Atherogenesis is associated with the upregulation of CD47, a key antiphagocytic molecule that is known to render malignant cells resistant to programmed cell removal, or "efferocytosis." Here, we have developed platelet membrane-coated mesoporous silicon nanoparticles (PMSN) as a drug delivery system to target atherosclerotic plaques with the delivery of an anti-CD47 antibody. Briefly, the cell membrane coat prolonged the circulation of the particles by evading the immune recognition and provided an affinity to plaques and atherosclerotic sites. The anti-CD47 antibody then normalized the clearance of diseased vascular tissue and further ameliorated atherosclerosis by blocking CD47. In an atherosclerosis model established in ApoE^-/- mice, PMSN encapsulating anti-CD47 antibody delivery significantly promoted the efferocytosis of necrotic cells in plaques. Clearing the necrotic cells greatly reduced the atherosclerotic plaque area and stabilized the plaques reducing the risk of plaque rupture and advanced thrombosis. Overall, this study demonstrated the therapeutic advantages of PMSN encapsulating anti-CD47 antibodies for atherosclerosis therapy, which holds considerable promise as a new targeted drug delivery platform for efficient therapy of atherosclerosis.

Effects of rehabilitation exercise on coronary artery after percutaneous coronary intervention in patients with coronary heart disease: a systematic review and meta-analysis

Purpose: The purpose of this study is to evaluate the effects of rehabilitation exercise on coronary artery of the patients with coronary heart disease (CHD) after percutaneous coronary intervention (PCI).Methods: We searched Medline, EMBASE, Cochrane CENTRAL databases, ISI Web of Science databases, Chinese Biological Medicine Data Base, Chinese knowledge resources, and Wan Fang database. Two researchers independently screened the literature databases, and assessed methodological qualities using the Physiotherapy Evidence Database scale and extracted data.Results: The coronary restenosis rate in rehabilitation exercise group was 10.8% (23/212), and that in the control group was 21% (48/229). Patients with rehabilitation exercise showed a significant reduction in restenosis rate, compared to the control group ((pooled OR: 0.46, 95% CI: 0.26-0.82, p < 0.01); heterogeneity: Chi²=3.86, df =5 (p = 0.57); I²=0%). In addition, the late luminal loss per stent in the rehabilitation exercise group was significantly smaller than that in the control group ((pooled MD: -0.33, 95% CI: -0.52 to -0.13, p < 0.01); heterogeneity: Chi²=0.27, df =1 (p = 0.60); I²=0%).Conclusions: Appropriate rehabilitation exercise reduces the incidence of coronary restenosis after PCI in patients with CHD and contributes to a significant reduction in late luminal loss in the stented coronary segment.Implications for RehabilitationAppropriate rehabilitation exercise can reduce the incidence of coronary restenosis after percutaneous coronary intervention in patients with coronary heart disease.Appropriate rehabilitation exercise contributes to a reduction in late luminal loss in the stented coronary segment.

Impact of exercise-based cardiac rehabilitation on de novo coronary lesion in patients with drug eluting stent

Objective

To compare the rate of progression of de novo lesion between the cardiac rehabilitation (CR) and control groups.

Methods

This is a retrospective observational study. Patients who received drug-eluting stent (DES) due to acute coronary syndrome were included as subjects. The CR group received eight weeks of early CR program, and sustained a self-exercise program in the homes. The control group was instructed to exercise independently. Nine months after the first insertion of DES, we implemented follow-up coronary angiography, and compared the rate of progression of de novo lesion by quantitative angiographic measurement between the two groups.

Results

A total of 81 patients were recruited as subjects to CR group (n=32) or control group (n=49). At nine months, late luminal loss was 0.04±0.23 mm in the CR group and 0.00±0.31 mm in the control group (p=0.54, observed power=0.10). Late loss was -0.90%±9.53% in the CR group and 0.80%±11.15% in the control group (p=0.58, observed power=0.05). No target lesion revascularization procedures were needed in the CR group, while two in the control group (p=0.25). In the CR group, mean VO_2max was significantly improved from 24.36±5.00 to 27.68±5.24 mL/kg/min (p<0.001).

Conclusion

We could not observe a statistically significant difference in the progression rate of de novo lesion between the CR and control groups. Thus the current amount of nine months exercise-based CR program does not seem to have a distinct impact on the retardation of de novo coronary lesion in patients who received percutaneous coronary intervention with DES.

Impact of Exercise-based Cardiac Rehabilitation on In-stent Restenosis with Different Generations of Drug Eluting Stent

Objective

To compare the rate of restenosis between a cardiac rehabilitation (CR) group and a control group within three different generations of drug eluting stents (DES).

Method

Patients who received DES due to an acute coronary syndrome were included. They were divided into a CR group and a control group. The CR group received six to eight weeks of early cardiac rehabilitation program in a hospital setting, and sustained a self-exercise program for six months in a community. The control group was instructed to exercise by themselves after leaving the hospital. Nine months after the first onset of disease, we implemented a coronary angiography and compared the two groups. In addition, we divided the patients into three subgroups according to the generation of DES, and compared the rate of restenosis between the CR group and control group within these three subgroups.

Results

At 9 months, in-stent restenosis, measured as an in-segment late luminal loss (LLL) of the stented coronary area, was smaller in the CR group (n=52) 0.16±0.42 mm compared to the control group (n=51) 0.39±0.78 mm (p<0.05). A reduction of LLL in the CR group compared to the control group was consistent among the three different generations of DES.

Conclusion

The CR program is strongly associated with a significant reduction in LLL in the stented coronary segments, regardless of the generation of DES.

Duration of dual antiplatelet therapy following percutaneous coronary intervention with drug-eluting stents: a review of recent evidence

The introduction of drug-eluting stents represented a significant advancement in interventional cardiology, offering a solution to the long-standing problem of restenosis after coronary revascularization. At present, drug-eluting stents are being used in a majority of stent procedures. However, they are mechanistically prone to develop late stent thrombosis and require prolonged therapy with aspirin and a thienopyridine to prevent this complication. Adequate evidence regarding the optimal duration of dual antiplatelet therapy is lacking, and the initial guidelines on this issue were framed empirically in the absence of robust data from clinical trials and analyses. In this article, we briefly review the evolution of dual antiplatelet therapy and discuss the findings from some recent analyses that test both the efficacy as well as the safety of extended and intensive platelet inhibition with aspirin and thienopyridines.

Journey in antithrombotic strategies for ST-elevation myocardial infarction

Our understanding and treatment of the ST-elevation myocardial infarction (STEMI) has led to a tremendous improvement in the care and preservation of life affecting millions yearly. As the medical community continues to discover novel strategies in therapeutics and innovations in prevention, it is imperative to understand the scientific journey the treatment of STEMI has traveled. Furthermore, the research pillars that led to our understanding of the current paradigm of STEMI will be highlighted in an effort to illuminate the foundation on which we now stand.

High-intensity interval training may reduce in-stent restenosis following percutaneous coronary intervention with stent implantation A randomized controlled trial evaluating the relationship to endothelial function and inflammation

BACKGROUND

High-intensity interval training has been shown to be superior to moderate continuous exercise training in improving exercise capacity and endothelial function in patients with coronary artery disease. The objective of this study was to evaluate this training model on in-stent restenosis following percutaneous coronary intervention for stable or unstable angina.

METHODS AND RESULTS

We prospectively randomized 40 patients after percutaneous coronary intervention with implantation of a bare metal stent (n = 30) or drug eluting stent (n = 32) to a 6-month supervised high-intensity interval exercise training program (n = 20) or to a control group (n = 20). At six months, restenosis, measured as in-segment late luminal loss of the stented coronary area, was smaller in the training group 0.10 (0.52) mm compared to the control group 0.39 (0.38) mm (P = .01). Reduction of late luminal loss in the training group was consistent with both stent types. Peak oxygen uptake increased in the training and control group by 16.8% and 7.8%, respectively (P < .01). Flow-mediated dilation improved 5.2% (7.6) in the training group and decreased -0.1% (8.1) in the control group (P = .01). Levels of high-sensitivity C-reactive protein decreased by -0.4 (1.1) mg/L in the training group and increased by 0.1 (1.2) mg/L in the control group (P = .03 for trend).

CONCLUSIONS

Regular high-intensity interval exercise training was associated with a significant reduction in late luminal loss in the stented coronary segment. This effect was associated with increased aerobic capacity, improved endothelium function, and attenuated inflammation.

Target vessel revascularization following percutaneous coronary intervention. A 10-year report from the Danish Percutaneous Transluminal Coronary Angioplasty Registry

OBJECTIVE

To present the rate of target vessel revascularization (TVR) in a consecutive and unselected national population over 10 years.

DESIGN

From 1989 to 1998 all percutaneous coronary interventions (PCIs) performed in Denmark were recorded in the Danish PTCA Registry.

RESULTS

From 1989 to 1998 the annual rate of PCI rose from 46 to 753 per million inhabitants. From 1995 to 1998 TVR with PCI or coronary artery bypass grafting (CABG) within 9 months from the index PCI decreased significantly (p < 0.001) from 21.2% in 1995 (CABG 8.6% vs PCI 12.6%) to 11.7% in 1998 (CABG 4.3% vs PCI 7.4%). Independent predictors for TVR were: coronary stenting (OR 0.60; 95% CI 0.52-0.69, p < 0.001), primary success rate (OR 0.69; 95% CI 0.53-0.89, p < 0.005), pre-PCI stenosis severity (OR 1.01; 95% CI 1.00-1.01, p = 0.03), left anterior descending coronary artery (OR 2.35; 95% CI 1.73-3.19, p < 0.001), right coronary artery (OR 1.61; 95% CI 1.17-2.20, p = 0.003), sapheneous vein graft (OR 2.03; 95% CI 1.13-3.63, p = 0.017) and age (OR 0.99; 95% CI 0.98-1.00, p = 0.002).

CONCLUSION

Coronary stenting, primary success rate, pre-PCI stenosis severity, age and treated vessel were independent predictors for TVR.

Very Late Stent Thrombosis After Dual Antiplatelet Therapy Discontinuation in a Patient with a History of Acute Stent Thrombosis

Objective:

To describe a case of very late stent thrombosis after dual antiplatelet discontinuation in a patient with a previous history of stent thrombosis.

Case Summary:

A 62-year-old man with a history of coronary artery disease, multiple acute coronary syndromes requiring percutaneous coronary interventions with multiple stent placements, and acute stent thrombosis resulting in ST segment elevation myocardial infarction presented to the hospital with chest pain. The chest pain was not relieved by 4 sublingual nitroglycerin tablets. Five days prior to his presentation, the patient had been instructed to discontinue both aspirin and clopidogrel in preparation for a left ankle fusion procedure. He was taken to the cardiac catheterization laboratory where he was found to have thrombosis in a sirolimus-eluting stent placed more than 3 years ago. Thrombectomy and balloon angioplasty were performed, and the patient completed his hospital course without complications.

Discussion:

Stent thrombosis associated with drug-eluting stents is a complicated pathophysiologic phenomenon with multiple patient-, procedure-, and device-related factors. Application of these risk factors to quantify the risk of stent thrombosis as they apply to a single patient is unknown. Discontinuation of recommended dual antiplatelet therapy with aspirin plus a thienopyridine has been identified as a major risk factor for stent thrombosis, but the optimal duration of dual antiplatelet therapy remains unknown. Current recommendations suggest extending dual antiplatelet therapy beyond one year in patients with low bleeding risk.

Conclusions:

Given the overall data at this time and the severity of stent thrombosis, it seems prudent to continue dual antiplatelet therapy with aspirin indefinitely plus a thienopyridine for at least one year, with continuation beyond one year on a case-by-case basis depending on the risks of in-stent thrombosis and bleeding. In patients with a low risk of bleeding, indefinite continuation of dual antiplatelet therapy may be reasonable.

Left main coronary artery stenosis: state-of-the-art

Patients with stenosis of the left main coronary artery present difficult challenges. The risks associated with this lesion have been known since the early days of angiography when patients were found to have increased mortality during follow-up. This information led to the general guidelines that surgical revascularization should be considered the treatment of choice in patients with significant left main coronary artery stenosis. Current advances in invasive cardiology have brought important information to the field. Intravascular ultrasound is now used routinely to evaluate angiographically indeterminate lesions with criteria now set forward as to what constitutes an indication for revascularization. Stents have even further dramatically changed the landscape. There are substantial issues, however, that need to addressed. These include the following: (1) the effect of specific lesion location on outcome - it is known that patients with distal bifurcation left main disease have worse outcome; (2) the potential for subacute thrombosis of the left main coronary artery; (3) the impact of left ventricular function and patient comorbidities irrespective of the degree and location of left main coronary artery stenosis; and (4) the risk-benefit ratio of stenting versus coronary artery bypass graft surgery. These issues are currently being addressed in two seminally important trials including the SYNTAX trial, which randomizes patients with left main and/or three-vessel disease to either coronary artery bypass graft surgery or a TAXUS drug-eluting stent. This trial is in the final stages of patient recruitment and will have important implications for the field. The other trial is the COMBAT trial, which is focused exclusively on left main coronary artery stenosis and randomizes patients with left main coronary artery disease either to a Sirolimus-eluting stent (Cypher, Johnson and Johnson Cordis, USA) or to coronary artery bypass graft surgery. The field of left main coronary artery disease continues to expand in terms of the evidence available for optimal patient evaluation and selection of treatment modalities.

Predictors of repeat revascularization after nonemergent, first percutaneous coronary intervention in the community

BACKGROUND

We sought to determine the incidence of and risk factors for repeat revascularization after nonemergent, first percutaneous coronary intervention (PCI) performed in contemporary community practice.

METHODS

We analyzed a prospective registry of consecutive patients undergoing isolated PCI in the state of Washington. Multivariate Cox regression analysis was used to determine predictors of repeat revascularization (by PCI or bypass surgery) within 1 year after first PCI.

RESULTS

Between January 1, 1999, and December 31, 1999, there were 3571 nonemergent first PCIs, 87.7% of which involved stent placement. Repeat revascularization occurred in 577 (16.2%) patients. Repeat revascularization was predicted by multivessel disease (hazard ratio [HR] 1.36, 95% CI 1.12-1.66), stable versus no angina (HR 1.27, 95% CI 1.03-1.57), and maximum stent length used (per 1 mm longer: HR 1.01, 95% CI 1.002-1.02), while prior myocardial infarction (HR 0.77, 95% CI 0.62-0.96) and creatinine >1.2 mg/dL (HR 0.74, 95% CI 0.56-0.98) were associated with lower risk of repeat revascularization. Diabetes was a significant predictor only when the outcome was limited to revascularization by coronary artery bypass surgery (HR 1.52, 95% CI 1.03-2.23). Although glycoprotein IIb/IIIa inhibitor use was a significant univariate predictor of freedom from early repeat revascularization (within 60 days after first PCI), after controlling for potential confounders, it was no longer significant.

CONCLUSIONS

In this contemporary, community-based registry of patients undergoing nonemergent first PCI, clinical practice and outcomes are consistent with evidence from clinical trials and previous controlled studies. Results from controlled studies may reasonably be extrapolated to such a community setting.

Evolving Complexity of Open Aortofemoral Reconstruction Done for Occlusive Disease in the Endovascular Era

Available endovascular and less invasive surgical interventions have diminished the need for aortofemoral bypass (AFB) construction for chronic inflow occlusive disease but have potentially increased its complexity. We reviewed our results with AFB done in 107 consecutive patients between 1997 and June 2002 (83 men, 24 women, mean age 62 +/- 7 years) with chronic limb ischemia due to aortoiliofemoral occlusive disease. Perioperative factors and surgical outcomes (<30 days) were evaluated and compared between patients requiring complex (redo AFB, need for visceral aortic clamp for juxtarenal occlusion, adjunctive visceral revascularization, or simultaneous inflow/outflow bypass) and conventional reconstructions by contingency table analysis. AFB was done for limb threat in 65 patients (61%) and 44 patients (41%) had failed previous inflow procedures (22 endovascular, 43 open; 1.5/patient). Operative complexity (36 patients, 34%) was evidenced by the need for redo AFB in 8 patients, suprarenal (13) or supramesenteric/celiac (6) aortic clamp and pararenal endarterectomy in 19 cases, adjunctive renal (10) or mesenteric (2) revascularization, or simultaneous construction of AFB and femoropopliteal/tibial bypasses in 9 patients. Overall AFB operative mortality and major complication rates were 3.7% ( n = 4) and 34% ( n = 36), respectively. Mortality ( p = 0.32) and nonvisceral related complications ( p = 0.3) were not statistically more frequent after complex AFB (5.6%, 31%) than after conventional reconstructions (2.8%, 21%). However, renal, mesenteric, or spinal cord (visceral) ischemic complications or death (10.3%) were greater after complex reconstructions (19.4%) than after conventional AFB (5.6%) ( p = 0.03). Pre-existing renal insufficiency (Cr >/=1.5, n = 9) was not predictive of postoperative renal failure (>2x preop Cr, n = 7) in this series ( p = 0.4). Our recent experience with AFB suggests its increasing use as a tertiary modality after failed endovascular or less invasive open reconstructions. Despite the added operative complexity associated with manipulation of the visceral aorta and its branches and the need for extended infrainguinal revascularization, satisfactory clinical outcomes can be achieved.