Asymptomatic Cardiac Ischemia Pilot (ACIP) Study. Improvement of cardiac ischemia at 1 year after PTCA and CABG

Fibrinogen and Fibrinolytic Activity in Capd Patients with Atherosclerosis and Its Correlation with Serum Albumin

Objective

It has been suggested that hypoalbuminemia in dialysis patients leads to a hypercoagulable state, however, the relationship between serum albumin and fibrinogen or fibrinolytic activity has not been well-documented. The aim of this study was to investigate the changes of fibrinogen, tissue plasminogen activator (tPA), plasminogen activator inhibitor type-1 (PAI-1), and lipid levels in continuous ambulatory peritoneal dialysis (CAPD) patients with atherosclerosis, and the relationship between those factors and serum albumin.

Design

A cross-sectional study.

Setting

A university hospital.

Patients

Twenty CAPD patients with atherosclerosis, 49 CAPD patients without atherosclerosis, and 33 normal controls were included. Presence of atherosclerosis was determined by positive results in a stress thallium singlephoton emission computed tomography or an ankle brachial index less than 0.9. Coronary angiography and/ or Doppler ultrasound of extremities were followed for the patients with positive results to confirm atherosclerotic cardiovascular disease.

Main outcome measures

tPA and PAI-1 levels were determined with ELISA method, and fibrinogen with thrombin time method. Serum albumin and lipids were also measured.

Results

Serum albumin and HDL -cholesterol levels were significantly lower, and the ratio of total cholesterol/ HDL was significantly higher, in CAPD patients than in normal controls. CAPD patients with atherosclerosis had significantly higher fibrinogen, tPA, and PAI-levels than other groups. tPA was an independent predictor of atherosclerotic vascular disease in CAPD patients in stepwise logistic regression analysis. Serum albumin level was inversely correlated with fibrinogen (r = -0.28; p < 0.05) in CAPD patients, but not with tPA or PAI-1 levels. PAI-1 level was correlated with tPA (r = 0.37; p < 0.01) and triglycerides (r = 0.32; p < 0.05).

Conclusions

Association of high levels of fibrinogen and PAI-1 with lipid disorders may be of importance in the development of atherosclerosis in CAPD patients. Hypoalbuminemia may contribute to atherosclerosis via increased synthesis of fibrinogen.

Use of a Load Distributing Band Device (with Ventilation Prompts) during Cardiopulmonary Resuscitation

Introduction

Over-ventilation can compromise coronary perfusion pressures during cardiopulmonary resuscitation (CPR) and should be minimised. We compared ventilations during manual and mechanical (load-distributing band - LDB) CPR, which gives ventilation prompts. Our primary objective was to compare the ventilation rate between manual CPR and LDB-CPR.

Method

This was a phased, non-randomised study at a tertiary hospital emergency department. All out-of-hospital, non-traumatic cardiac arrest adult patients during the study period from February 2007 till July 2008 were eligible. Pregnant females and patients aged less than 18 years of age were excluded. Ventilation rates in the first and second 5 minutes segments were recorded. Over-ventilation was defined as ventilation rate above 12 breaths per minute. All data analyses were performed with SPSS, version 17.0. Mean differences with 95% confidence interval (CI) were compared between the 2 treatment groups.

Results

From February 2007 till August 2007, there were 29 patients with manual CPR; and from September 2007 till July 2008, there were 62 with LDB-CPR. In the first 5 minutes of CPR, the proportion of patients that were over-ventilated, was 27.6% (manual) and 4.8% (LDB) (difference = 22.7%; 95% CI: 3.5-46.4%). In the next 5 minutes, the proportion of patients that were over-ventilated was 37.9% and 1.6% for manual and mechanical CPR respectively (difference = 36.3%; 95% CI: 16.5-58.9%).

Conclusion

Over-ventilation is reduced significantly in LDB-CPR compared to manual CPR during the first and second 5 minutes of resuscitation.

Techniques for Endovascular Recanalization of Supra-Aortic Trunks

The supra-aortic arteries are no stranger to endovascular interventions. Since the 1980s, interventionists have been evaluating and refining the use of transluminal techniques for recanalizing stenotic and occlusive lesions in these large-bore, high-flow vessels. The authors present their methodologies for evaluating, selecting, and treating supra-aortic lesions with balloon angioplasty and stenting. Helpful suggestions are offered for optimizing the outcome of these endovascular approaches to atherosclerotic occlusive disease in the supra-aortic trunks.

The Hydrolyser Thrombectomy Catheter: A Single-Center Experience

Purpose:

To present a single-center experience with a mechanical hydrodynamic thrombectomy system (Hydrolyser) in native arteries, veins, and bypass grafts.

Methods:

The Hydrolyser is a 7F, double lumen, over-the-wire thrombectomy catheter. The device was used in 41 patients (22 males; mean age 68 years, range 40 to 90), with recent thromboses (aged 1 to 30 days, mean 8.7 ± 8.5), measuring from 4 to 35 cm long (mean 17.7 ± 9.5). The occlusions were located in native lower limb arteries (n = 28), bypass grafts (n = 8), superior venae cavae (n = 2), axillary vein (n = 1), and pulmonary arteries (n = 2).

Results:

Immediate technical success (residual clot < 50% of lumen diameter) was achieved in 34 patients (83%): 22/28 native arteries (78%), 7/8 bypass grafts (87%), and all pulmonary arteries, superior venae cavae, and the axillary vein. The 7 failed patients were treated surgically (bypass graft or Fogarty balloon). Adjunctive procedures were used to maximize luminal diameter: angioplasty (n = 29, with 13 immediate stent implantations), thromboaspiration (n = 17), and thrombolysis (n = 10). One case of distal embolism was the only complication (treated by thromboaspiration). At 30 days, 30 (73%) vessels remained patent.

Conclusions:

The Hydrolyser system is a promising concept for percutaneous thrombectomy. It is a quick, reliable, efficient device that may offer an alternative to thrombolysis and surgical thrombectomy.

Endovascular Management of Unusual Aneurysms of the Axillary and Subclavian Arteries

Purpose:

Aneurysms of the upper extremity arteries are uncommon and may be difficult to manage with standard surgical techniques. We report the exclusion of three axillary-subclavian aneurysms with covered stents.

Methods and Results:

Palmaz stents were covered with either polytetrafluoroethylene (2 cases) or brachial vein and deployed to exclude pseudoaneurysms in 1 axillary (ruptured) and 2 left subclavian arteries. Two of the patients had advanced cancer and died within 52 days and 3 months of treatment, but their aneurysms were occluded at the time of their death. The repair in the third patient is patent at 9 months.

Conclusions:

Endovascular exclusion of axillary and subclavian aneurysms with covered stents may offer a useful alternative to operative repair, particularly in patients with significant comorbidities.

Stenting in the Carotid Artery: Initial Experience in 110 Patients

Purpose:

To evaluate the feasibility, safety, and efficacy of intravascular stents in the treatment of extracranial carotid artery occlusive disease.

Methods:

According to protocol, stent therapy was offered to symptomatic patients with ≥ 70% arteriographically defined carotid stenoses or ulcerative lesions and, after September 1994, to asymptomatic patients with ≥ 75% stenoses. From April 1993 to September 1995, 110 nonconsecutive patients (79 males; mean age 72 years, range 45 to 85) consented to participate in the study. The majority (79 [72%]) were asymptomatic. Lesions meeting the treatment criteria were in the proximal common (n = 3); mid common (n = 12); distal common (n = 8); internal (ICA) (n = 92); and external (n = 2) carotid arteries. Seven patients had bilateral ICA stenoses, and 17 patients were treated for postsurgical recurrent disease. The mean lesion length and diameter stenosis for all lesions were 12.4 ± 9.2 mm and 86.5% ± 10.6%, respectively. The procedures were performed either via direct percutaneous access to the cervical common carotid artery or through a retrograde femoral artery approach. Standard balloon dilation preceded deployment of balloon-expandable stents in most cases. No postprocedural anticoagulation was used (aspirin only).

Results:

In 110 patients (117 arteries) intended for treatment, 109 (99.0%) (116 arteries [99.1%]) were successfully treated with 129 stents (128 Palmaz, 1 Wallstent). One percutaneous procedure failed (0.9%) for technical reasons (stent could not be deployed) and was converted to carotid endarterectomy. Minor complications included 4 cases of spasm (successfully treated with papaverine); 1 flow-limiting dissection (stented); and 6 access-site problems. There were 7 strokes (2 major, 5 reversible) (6.4%) and 5 minor transient events (4.5%) that resolved within 24 hours. Three patients were converted to endarterectomy (2.7%) prior to discharge; 1 stroke patient expired (0.9%), and another patient died of an unrelated cardiac event in hospital. In the 30-day postprocedural period, 2 ICA stents occluded (patients asymptomatic). Clinical success at 30 days (no technical failure, death, endarterectomy, stroke, or occlusion) was 89.1% (98/110). Over a mean 7.6-month follow-up (range 2 to 31), no new neurological symptoms developed. Another stent occlusion at 2 months and one case of flow-limiting intimal hyperplasia at 7 months were detected on routine duplex scanning in asymptomatic patients. Life-table analysis shows an 89% cumulative primary patency rate.

Conclusions:

Based on this early experience, carotid stenting appears feasible from a technical standpoint, with good midterm patency. However, the incidence of neurological sequelae is a serious problem. Technical enhancements and a more aggressive antiplatelet regimen may have a positive impact on these events.

Does coronary Atherosclerosis Deserve to be Diagnosed earlY in Diabetic patients? The DADDY-D trial. Screening diabetic patients for unknown coronary disease

OBJECTIVES

To evaluate if screening and treatment of asymptomatic coronary artery disease (CAD) are effective in preventing first cardiac event in diabetics.

METHODS

Diabetic patients without known CAD were randomly assigned to undergo a screening for silent myocardial ischemia followed by revascularization or to continue follow-up. The reduction of cardiac death (CD) or nonfatal myocardial infarction (MI) represented the primary aim; secondary aim was the prevention of heart failure (HF).

RESULTS

From September 2007 to May 2012, 520 patients (62 years; 104 female) were enrolled. Silent CAD was found in 20 of 262 patients (7.6%), revascularization was performed in 12 (4.6%). After a mean follow-up of 3.6 years 12 events (4.6%) occurred in the study group and 14 (5.4%) in the follow-up (HR=0.849, 95% CI: 0.393-1.827, P=0.678). The occurrence of first HF episode did not differ between groups: 2 (0.8%) in screened and 7 (2.7%) in follow-up (HR=0.273, 95% CI: 0.057-1.314, P=0.083). Subgroup analysis revealed a significantly lower HF episodes among patients with intermediate cardiovascular risk (Log rank P=0.022). Additionally, when CD and MI were analysed within subgroups, a significant lower number of CDs was observed among older than 60 years (P=0.044).

CONCLUSION

Screening and revascularization of silent CAD in diabetics, failed to demonstrate a significant reduction in cardiac events and HF episodes. However, our data indicate that further research is warranted in patients older than 60 years and those with an intermediate cardiovascular risk. CLINICALTRIALS.GOV: NCT00547872.

Curative surgery for atrial fibrillation: current status and minimally invasive approaches

Atrial fibrillation (AF) is the most common disorder of heart rhythm. Affecting 2.2 million Americans and millions more worldwide, AF is a dangerous and costly epidemic. AF is associated with an increased risk of stroke, premature death and billions of dollars in healthcare expenditures. Traditional treatments of AF, which include medications aimed at rate or rhythm control have been disappointing, leaving most patients in AF and failing to eliminate the risk of stroke. In contrast, advances in surgical and catheter-based therapies offer the chance to cure AF. With more than a decade of experience, surgical treatment of AF is the most effective means of curing this arrhythmia. The classic Maze procedure eliminates AF in more than 90% of patients. A complex but safe operation, the Maze procedure is applied by relatively few surgeons. Recently, however, there has been a resurgence of interest in surgical treatment of AF. Advances in the understanding of the pathogenesis of AF and development of new ablation technologies enable surgeons to perform pulmonary vein ablation and create linear left atrial lesions rapidly and safely. Such procedures, which are generally applied to patients with AF and valvular heart disease, add 15 minutes to operative time and cure AF in approximately 80% of patients. New ablation technologies have been adapted to enable thoracoscopic and minimally invasive surgical AF ablation in patients with isolated AF, extending the possibility of cure to large numbers of patients.

Hyperhomocysteinemia and cardiovascular disease: new mechanisms beyond atherosclerosis

The association of hyperhomocysteinemia (Hhe) with cardiovascular disease (CVD) has been explored in detail over the last four decades since initial reports in the 1960s. Although several epidemiological studies have shown an association, convincing mechanistic studies are still lacking. However, recent prospective studies demonstrate a strong association of Hhe with coronary disease. Several pathogenic mechanisms have been studied in Hhe and indicate alterations in the various components of vascular disease, namely endothelial cells, vascular smooth muscle cells, platelets, and the coagulation/fibrinolytic systems. Increased oxidative stress, hypomethylation, and protein homocysteinylation have been proposed as potential molecular mechanisms in Hhe-induced CVD. In addition, recent studies indicate a novel link between Hhe and CVD, that is, direct effects on coronary arteriolar and myocardial remodeling resulting in cardiac dysfunction.

C-terminus of heat shock protein 70-interacting protein-dependent GTP cyclohydrolase I degradation in lambs with increased pulmonary blood flow

We showed that nitric oxide (NO) signaling is decreased in the pulmonary vasculature before the development of endothelial dysfunction in a lamb model of congenital heart disease and increased pulmonary blood flow (Shunt). The elucidation of the molecular mechanism by which this occurs was the purpose of this study. Here, we demonstrate that concentrations of the endogenous NO synthase (NOS) inhibitor, asymmetric dimethylarginine (ADMA), are elevated, whereas the NOS cofactor tetrahydrobiopterin (BH(4)) is decreased in Shunt lambs. Our previous studies demonstrated that ADMA decreases heat shock protein-90 (Hsp90) chaperone activity, whereas other studies suggest that guanosine-5'-triphosphate cyclohydrolase 1 (GCH1), the rate-limiting enzyme in the generation of BH(4), may be a client protein for Hsp90. Thus, we determined whether increases in ADMA could alter GCH1 protein and activity. Our data demonstrate that ADMA decreased GCH1 protein, but not mRNA concentrations, in pulmonary arterial endothelial cells (PAECs) because of the ubiquitination and proteasome-dependent degradation of GCH1. We also found that Hsp90-GCH1 interactions were reduced, whereas the association of GCH1 with Hsp70 and the C-terminus of Hsp70-interacting protein (CHIP) increased in ADMA-exposed PAECs. The overexpression of CHIP potentiated, whereas a CHIP U-box domain mutant attenuated, ADMA-induced GCH1 degradation and reductions in cellular BH(4) concentrations. We also found in vivo that Hsp90/GCH1 interactions are decreased, whereas GCH1-Hsp70 and GCH1-CHIP interactions and GCH1 ubiquitination are increased. Finally, we found that supplementation with l-arginine restored Hsp90-GCH1 interactions and increased both BH(4) and NO(x) concentrations in Shunt lambs. In conclusion, increased concentrations of ADMA can indirectly alter NO signaling through decreased cellular BH(4) concentrations, secondary to the disruption of Hsp90-GCH1 interactions and the CHIP-dependent proteasomal degradation of GCH1.

Screening asymptomatic patients with diabetes for unknown coronary artery disease: does it reduce risk? An open-label randomized trial comparing a strategy based on exercise testing aimed at revascularization with management based on pharmacological/behavioural treatment of traditional risk factors. DADDY-D Trial (Does coronary Atherosclerosis Deserve to be Diagnosed and treated early in Diabetics?)

BACKGROUND

Coronary artery disease is the leading cause of morbidity and mortality in patients with type 2 diabetes. Screening for asymptomatic coronary artery disease with treatment by means of revascularization seems to be an appealing option for prevention. The utility of such a strategy has never been challenged in a randomized trial.

METHODS/DESIGN

In the present study a cohort of diabetic patients without any symptoms and without known coronary artery disease will be screened at two diabetes outpatients services. Those with intermediate or high risk (equal or greater than 10% according to the Italian risk chart) will be asked to participate and enrolled. They will be seen and followed in order to provide the best adherence to medical therapy. Half of the patients will be randomized to undergo an exercise tolerance testing while the other group will continue to be regularly seen at diabetes outpatients services. Best medical/behavioral therapy will be offered to both groups. Those patients with a positive exercise tolerance testing will be studied by coronary angiography and treated according to the severity of coronary lesions by percutaneous stenting or surgery.The objective of the study is to evaluate the efficacy of the screening strategy aimed at revascularization. A cost-effectiveness analysis will be performed at the end of the follow up.

DISCUSSION

The study will provide useful information about prevention and treatment of diabetic patients at high risk of coronary events. It will be made clearer if detection of silent coronary artery disease has to be recommended and followed by treatment. Given the simplicity of the study protocol, it will be easily transferable to the real world.

TRIAL REGISTRATION

(ClinicalTrials.gov): NCT00547872.

Oral administration of glycine in the prevention of restenosis after coronary angioplasty. A double blind placebo controlled randomized feasibility trial evaluating safety and efficacy of glycine in the prevention of restenosis after angioplasty

OBJECTIVES

Evaluation of safety, feasibility, and efficacy of oral administered glycine in prevention of angiographic restenosis six months after percutaneous coronary intervention (PCI).

BACKGROUND

The amino acid glycine modulates immunological response and enhances the production of endothelial derived nitric oxide (EDNO) factor. This factor has been shown to possess anti-atherosclerotic properties, actions of which are thought to reduce neo-intimal hyperplasia. Furthermore, glycine significantly elevates arginine serum levels. This amino acid has been extensively studied for its effects on the endothelium, nitric oxide (NO) metabolism and effects on several biochemical pathways interfering with the process of restenosis after PCI.

METHODS

A prospective double blind placebo controlled randomized study evaluated safety and feasibility of chronic oral administration of glycine. In addition, the efficacy was determined by evaluation of six months angiographic restenosis rates.

RESULTS

214 patients scheduled for elective PCI were randomized to receive glycine or placebo. At follow-up, there was no significant difference in side effects and in major adverse cardiac events (MACE) between both groups. Six-month angiograms revealed similar restenosis rates for the glycine group (17.5%) and for the placebo group (20.2%) (P = 0.82).

CONCLUSION

Chronic oral administration of glycine was safe and feasible and had similar side effects compared to placebo. However, chronic oral administration of glycine did not lead to a significant reduction in restenosis rates at six months after elective PCI.

Tachycardia-induced cardiomyopathy: mechanisms of heart failure and clinical implications

The prognosis of dilated cardiomyopathy is generally poor. The cause of ventricular dysfunction often cannot be identified. In most cases, the clinical history of cardiomyopathy is irreversible but, in some cases, potentially curable causes may be identified. The development of cardiomyopathy may be correlated to atrial or to ventricular arrhythmias. In this scenario, atrial fibrillation is the most frequent cause of ventricular dysfunction, even if it may also be secondary to heart failure. The diagnosis of tachycardia-induced cardiomyopathy can be made only after the improvement of the left ventricular function once the cardiac frequency has slowed down.

Reviewing myocardial silent ischemia: specific patient subgroups

Silent myocardial ischemia (SMI) is a relatively common, yet poorly understood, clinical entity. The most accurate means of detecting SMI and the precise treatment endpoints remain unclear. However, the presence of SMI correlates with the likelihood of future adverse cardiac events. Evidence suggests that patients at high risk of severe cardiac ischemia, even with the absence of symptoms, derive the greatest benefit from an aggressive diagnostic and therapeutic approach. This paper is giving a detailed review of SMI in regards to specific patient subgroups, i.e. populations with diabetes mellitus, hypertension, elderly patients, post-revascularization patients, women, the suggested screening procedures for each subgroup, as well as the emersion of new markers for the selection of high-risk patients for screening.

Current strategies for the prevention of angina in patients with stable coronary artery disease

PURPOSE OF REVIEW

Angina pectoris affects at least 6.6 million people in the US and approximately 400,000 new cases of stable angina occur each year. Angina may be one of the first signs of ischemic heart disease, although it is likely not causally related to the likelihood of plaque rupture leading to an acute coronary syndrome. Modalities for treatment of angina should be used maximally to improve quality of life and decrease cardiovascular morbidity and mortality. The current recommended pharmacologic and invasive approaches, as well as novel therapies, are reviewed.

RECENT FINDINGS

Antiischemic agents, including beta-blockers, nitrates and calcium channel blockers, remain the mainstay in the prevention of angina. Revascularization via percutaneous interventions or coronary bypass surgery are appropriate in specific cases or when medical treatment fails. Noninvasive treatment options for refractory angina, metabolic agents, and vasodilator therapies are adding to the armamentarium to prevent and treat angina.

SUMMARY

A multifaceted approach is optimal to address the prevention of angina. Once angina is recognized, there are many modalities that lessen the incidence of daily life-induced and exercise-induced angina and ischemia. Angina management is best addressed by pharmacologic and lifestyle interventions.

Identifying which patients with diabetes should be tested for the presence of coronary artery disease – The importance of baseline electrocardiogram and exercise testing

Numerous studies have reported that diabetic patients should not always be considered to be coronary artery disease (CAD)-equivalent as was previously suggested. Exercise testing is widely available at a relatively low cost, and even among patients in whom the diagnosis of CAD is highly probable on the basis of age, sex, description of chest pain and history of prior myocardial infarction, exercise testing is often a clinical requirement for risk or prognosis assessment to determine the need for possible coronary angiography or revascularization. Nevertheless, because of either the presence of atypical symptoms or the absence of symptoms often encountered, the screening approach may differ in patients with diabetes mellitus. Because CAD is the major cause of mortality in patients with diabetes, its early detection is important to improve medical interventions and outcomes. This is critical because the available evidence suggests that occult CAD is common among asymptomatic patients with diabetes. Therefore, noninvasive testing for asymptomatic CAD may be helpful for the identification of diabetic patients with severe coronary obstruction in whom revascularization therapy may be considered the first manifestation of silent CAD in patients with diabetes is a fatal cardiac event in approximately one-half of the patients. The present paper reviews some clinical markers that may be helpful to the clinician to increase the yield of finding significant occult CAD while screening patients with diabetes.

Insight into the New Changes in European Resuscitation Council Guidelines for Adult Resuscitation (2005)

It is five years now since the last European resuscitation guidelines were published(1). The science of resuscitation has been enriched with further significant scientific evidence that has led to new evidence-based guidelines. These guidelines were released in November 2005 and published in the international Journal of Resuscitation, November 2005(2).

FLOCOR: a new anti-adhesive, rheologic agent

FLOCOR (purified poloxamer 188) is a surfactant molecule that represents a new class of pharmacological agent. FLOCOR is different in that its activity does not depend on high affinity receptor binding but rather on altering the way cells and molecules interact with water. Extensive preclinical studies in models of vascular occlusive disorders, including circulatory shock, acute stroke, and myocardial infarction (MI), suggest that iv. administration of poloxamer 188 improves microvascular blood flow in ischaemic tissues by inhibiting adhesive interactions, lowering blood viscosity and reducing friction along the vessel wall. In clinical studies, poloxamer 188 demonstrated statistically significant benefits in patients with acute myocardial infarction (AMI) and acute vaso-occlusive crisis of sickle cell disease. However, these studies were conducted with commercial grades of poloxamer 188 that contained nephrotoxic impurities, and elevated creatinine was observed in a small percentage of patients. A new highly purified version of poloxamer 188 free from impurities has been developed. Highly purified poloxamer 188 (trade name FLOCOR) is better tolerated in models of renal failure and is anticipated to have a significantly improved therapeutic index compared to commercial grade poloxamer 188. Clinical studies are now in progress in order to confirm the therapeutic benefits of FLOCOR (purified poloxamer 188).

The drug-based pipeline against restenosis

More than 1 million percutaneous coronary interventions (PCIs) are performed yearly worldwide. Restenosis is the recurrent narrowing that can occur within 6 months following an initially successful PCI. Although drug-eluting stents have accomplished remarkable success, restenosis has not been eliminated and optimisation of both the polymers and drugs associated with them is desirable. This article reviews the presently available and potential preventive approaches against restenosis, including the sirolimus and paclitaxel drug-eluting stents.

Exercise training in patients with severe chronic heart failure: impact on left ventricular performance and cardiac size. A retrospective analysis of the Leipzig Heart Failure Training Trial

BACKGROUND

Exercise training (ET) has been shown to improve functional work capacity in patients with stable chronic heart failure (CHF) having moderate symptoms (NYHA class II). This analysis was conducted, to evaluate the effects of ET on left ventricular function and haemodynamics in patients with advanced CHF (NYHA class III) fulfilling the inclusion criteria of the COPERNICUS trial.

METHODS

Seventy-three patients with moderate and advanced CHF were prospectively randomised to a training (n=36), or to a control group (n=37). At baseline and after six months, patients underwent echocardiography and symptom-limited ergospirometry with measurement of central haemodynamics by thermodilution.

RESULTS

Nine out of 37 patients in the control group (C) and 10 out of 36 patients in the training group (T) had symptoms of advanced CHF. Exercise training over a period of six months resulted in an improvement of functional status on average by one NYHA class in patients with advanced CHF. Moreover, oxygen uptake at the ventilatory threshold increased by 49% (from 7.7+/-1.0 to 11.4+/-0.4 mL/min/kg, P<0.01 versus baseline) and at peak exercise by 32% (from 16.3+/-1.6 to 21.5+/-1.2 mL/min/kg, P<0.01 versus baseline) in training patients. The small, but significant reduction in left ventricular end-diastolic diameter by 7% (from 70+/-2 to 66+/-2 mm; P<0.05 versus baseline) was accompanied by an augmentation in stroke volume at rest by 32% (from 45+/-3 to 60+/-6 mL, P<0.05 versus baseline) and at peak exercise by 27% (63+/-9 to 81+/-9 mL, P<0.05 versus baseline) as a result of ET in patients with advanced CHF.

CONCLUSIONS

In patients with advanced CHF (NYHA class III), long-term exercise training is associated with an enhanced physical work capacity, an improvement in stroke volume and a reduction in cardiomegaly.

Low level laser irradiation stimulates mitochondrial membrane potential and disperses subnuclear promyelocytic leukemia protein

BACKGROUND AND OBJECTIVES

Low level laser irradiation (LLLI) is used to promote wound healing. Molecularly it is known to stimulate mitochondrial membrane potential (MMP), cytokine secretion, and cell proliferation. This study was designed to determine the influence of LLLI on the kinetics of MMP stimulation and decay, specific cytokine gene expression, and subcellular localization of promyelocytic leukemia (PML) protein on HaCaT human keratinocytes.

STUDY DESIGN/MATERIAL AND METHODS

The cells were irradiated by a 780 nm titanium-sapphire (Ti-Sa) laser with 2 J/cm(2) energy density. MMP was monitored with Mitotracker, a mitochondrial voltage-sensitive fluorescent dye. Cytokine gene expression was carried out using semi-quantitative-reverse transcription polymerase chain reaction. Subcellular localization of PML protein, a cell-cycle checkpoint protein, was determined using immunofluorescent staining.

RESULTS

The fluorescence intensity of MMP was increased immediately after the end of LLLI by 148 +/- 6% over control (P<0.001). Subsequently it decayed, reaching 51 +/- 14% of the control level (P < 0.01) within 200 minutes. This decay was characterized by an exponential curve (R = 0.96) with a lifetime of 79 +/- 36 minutes (P < 0.05). Following irradiation, the expression of interleukin-1alpha, interleukin-6, and keratinocyte growth factor (KGF) genes were transiently upregulated; but the expression of the proinflammatory gene interleukin-1beta, was suppressed. The subnuclear distribution of PML was altered from discrete domains to its dispersed form within less than 1 hour after LLLI.

CONCLUSIONS

These changes reflect a biostimulative boost that causes a shift of the cell from a quiescent to an activated stage in the cell cycle heralding proliferation and suppression of inflammation. Further characterization of MMP kinetics may provide a quantitative basis for assessment of the effect of LLLI in the clinical setting.

Rate control versus rhythm control for the management of atrial fibrillation: the verdict of the AFFIRM trial

Atrial fibrillation is the most common sustained cardiac arrhythmia encountered in clinical practice that affects cardiovascular morbidity and mortality and generates significant healthcare costs. There are two approaches for the management of atrial fibrillation: rate control and rhythm control. Rate-control strategy involves using rate-controlling agents such as beta-blockers, calcium channel blockers or digoxin, or a combination thereof to control symptoms while allowing atrial fibrillation to persist. Rhythm-control strategy involves cardioversion and treatment with antiarrhythmic drugs to maintain sinus rhythm. Although each strategy has its own advantages as well as limitations, it has long been debated which of the strategies offers better long-term outcomes and thus should be the preferred and recommended approach for the management of patients with atrial fibrillation. The Atrial Fibrillation Follow-up Investigation of Rhythm Management (AFFIRM) study was the first large-scale randomised study to address this important issue. In this article, the long awaited verdict of the AFFIRM study with its implications for the clinical management of patients with atrial fibrillation is discussed.

Improvement of cardiorespiratory function after percutaneous transluminal coronary angioplasty or coronary artery bypass grafting

OBJECTIVE

The objective of this study was to investigate the effect of a 3-mo training program for patients with either a percutaneous transluminal coronary angioplasty (PTCA) or a coronary artery bypass grafting (CABG).

DESIGN

Forty-four patients participated in a 3-mo outpatient cardiac rehabilitation program. Graded exercise tests with gas analysis were conducted before and after training to evaluate the changes of cardiorespiratory function.

RESULTS

In the pretraining examination, the PTCA group showed a higher peak oxygen uptake (VO2peak) and work rate than the CABG group. In the posttraining examination, the PTCA group increased 14.6% in VO2peak. Meanwhile, the CABG group increased 32.8% in VO2peak. At the ventilatory threshold, both groups also significantly increased in Vo2.

CONCLUSIONS

A 3-mo cardiac rehabilitation program for patients with PTCA or CABG could favorably enhance their cardiorespiratory function. Although the pretraining VO2peak was lower for the patients with CABG, their training potential was greater, and hence they could achieve a similar level of aerobic capacity as the PTCA group.

Angiogenic Gene Therapy (AGENT) trial in patients with stable angina pectoris

BACKGROUND

The angiogenic response to myocardial ischemia can be augmented in animal models by gene transfer with the use of a replication defective adenovirus (Ad) containing a human fibroblast growth factor (FGF) gene.

METHODS AND RESULTS

The objectives of the Angiogenic GENe Therapy (AGENT) trial were to evaluate the safety and anti-ischemic effects of 5 ascending doses of Ad5-FGF4 in patients with angina and to select potentially safe and effective doses for subsequent study. Seventy-nine patients with chronic stable angina Canadian Cardiovascular Society class 2 or 3 underwent double-blind randomization (1:3) to placebo (n=19) or Ad5-FGF4 (n=60). Safety evaluations were performed at each visit and exercise treadmill testing (ETT) at baseline and at 4 and 12 weeks. Single intracoronary administration of Ad5-FGF4 seemed to be safe and well tolerated with no immediate adverse events. Fever of <1-day duration occurred in 3 patients in the highest-dose group. Transient, asymptomatic elevations in liver enzymes occurred in 2 patients in lower-dose groups. Serious adverse events during follow-up (mean, 311 days) were not different between placebo and Ad5-FGF4. Overall, patients who received Ad5-FGF4 tended to have greater improvements in exercise time at 4 weeks (1.3 versus 0.7 minutes, P=NS, n=79). A protocol-specified, subgroup analysis showed the greatest improvement in patients with baseline ETT < or =10 minutes (1.6 versus 0.6 minutes, P=0.01, n=50).

CONCLUSIONS

Results show evidence of favorable anti-ischemic effects with Ad5-FGF4 compared with placebo, and it appears to be safe. Angiogenic gene transfer with Ad5-FGF4 shows promise as a new therapeutic approach to the treatment of angina pectoris.

Physiologic atrial cardiac pacing for the prevention of chronic atrial fibrillation associated with sick sinus syndrome

Long-term results of physiologic atrial pacing have been analyzed for the possibility of avoiding the recurrence of paroxysmal atrial fibrillation and the progression to chronic permanent atrial fibrillation in patients with paroxysmal atrial fibrillation related to sick sinus syndrome. Seventy four patients were evaluated and divided into two groups; 39 patients underwent atrial pacing (AAI, 53%) and 35 had ventricular pacing by single-lead pacing (VVI, 47%). All patients had been evaluated periodically on an out-patient basis by 24 hour Holter monitoring. Basic rhythms in all AAI patients were based on atrial pacing, resulting from the suppression of paroxysmal atrial fibrillation. Basic rhythms in the VVI paced patients were variable, consisting of regular sinus rhythm, transient atrial fibrillation, and ventricular pacing in 30 of 35 patients in the VVI group. The remaining five patients progressed to chronic permanent atrial fibrillation (0% in AAI vs. 14% in VVI, p < 0.05). Thromboembolic complications were not observed in the AAI pacing group. Three patients demonstrated thromboembolic complications (0% in AAI vs. 8.6% in VVI, p < 0.05). The effect of preventing paroxysmal atrial fibrillation and the progression to chronic atrial fibrillation was evident in the AAI paced group, but VVI pacing cannot prevent paroxysmal atrial fibrillation and chronic atrial fibrillation. In addition, potential risks of thromboembolic complications caused by atrial fibrillation were not decreased in VVI paced patients.

Optimal dosing of intravascular low-power red laser light as an adjunct to coronary stent implantation: insights from a porcine coronary stent model

BACKGROUND

It is believed that restenosis following coronary interventions is the result of endothelial denudation that leads to thrombus formation, vascular remodeling, and smooth muscle cell proliferation. Low-power red laser light (LPRLL) irradiation enhances endothelial cell growth in vitro and in vivo, and reduces restenosis in animal models. The present study investigated the optimal dose of intravascular LPRLL therapy in the prevention of in-stent stenosis in a porcine coronary stent model.

METHODS AND RESULTS

Selected right coronary artery segments were pretreated with a LPRLL balloon, delivering a dose of 0 mW during 1 min (group 1, n = 10), 50 mW during 1 min (group II, n = 10), or 100 mW during 1 min (group III, n = 10) before stenting. Quantitative coronary analysis of the stented vessel was performed before stenting, immediately after stenting, and at 6 weeks follow-up. The pigs were sacrificed, and histologic and morphometric analyses were conducted. At 6 weeks, minimal luminal stent diameter was significantly narrower in the control group compared to the 50-mW dose group (p < 0.05). These results were confirmed by morphometric analysis. Neointimal area was also significantly decreased in the 50-mW dose group.

CONCLUSIONS

Intravascular LPRLL contributes to reduction of angiographic in-stent restenosis and neointimal hyperplasia in this animal model. The optimal dose using the LPRLL balloon system seems to be approximately 5 mW delivered during 1 min.

Ventricular free wall rupture in acute myocardial infarction

Despite a progressive reduction in acute myocardial infarction mortality over the years, death related to ventricular free wall rupture has not changed. This is mostly related to the catastrophic presentation and death within minutes in the majority of these patients. Once rupture is suspected, bedside echocardiography should be performed immediately, followed by pericardiocentesis and repair of the rupture site as quickly as possible. Measures to prevent cardiac rupture include the administration of beta-blockers and angiotensin-converting enzyme inhibitors unless contraindications exist, and the avoidance of steroidal and nonsteroidal anti-inflammatory agents such as ibuprofen and indomethacin.

Long-term outcome of angioplasty for multivessel coronary disease: importance and price of complete revascularization

BACKGROUND

Complete revascularization of multivessel coronary artery disease (MVD) by coronary artery bypass surgery has been shown to improve outcome, but there is a lack of similar data for patients treated by angioplasty.

METHODS

Therefore, a consecutive series of 250 patients with MVD was separated into two groups, those with complete revascularization (n=101) and those with incomplete revascularization (n=149). Six-month 'clinical restenosis' rate assessed by stress myocardial perfusion scintigraphy or symptom-driven angiography and long-term 32 months outcome were compared with an equally sized group of single vessel disease (SVD) patients.

RESULTS

MVD patients with complete revascularization had a higher 'clinical restenosis' rate than patients with SVD (35 vs. 22%, P<0.02), although restenosis rate per treated vessel was similar (23%, 18%, P NS). If this higher early restenosis rate were accepted as 'price' for complete MVD angioplasty, long-term event-free survival was no longer different from that of SVD patients (86 vs. 93%, P NS). In contrast, patients with incomplete multivessel angioplasty had a significantly worse long-term outcome (22% events), especially if initially untreated, non-occluded vessels remained untreated (25% events).

CONCLUSION

MVD angioplasty with complete revascularization has a long-term event-free survival similar to that of SVD angioplasty but at the price of a higher rate of 6-month restenosis and repeat interventions.

Revascularization of ischemic tissues with SIKVAV and neuropeptide Y (NPY)

Angiogenesis, the process of new vessel growth, is necessary for many normal physiological and pathological processes such as tumor growth, wound healing and ischemia. We have recently examined in vitro and in vivo the ability of two potent angiogenic compounds, SIKVAV (a peptide derived from the alpha chain of laminin-1) and Neuropeptide Y (NPY) to revascularize ischemic tissue. These compounds were tested in an ex vivo capillary sprouting angiogenesis assay that uses rat aortic rings. Both NPY and SIKVAV in the presence of VEGF, stimulated the formation of long sprouts at concentrations of 1 ng NPY (0.2 pmol/L) and 100 micrograms SIKVAV. In comparison very little sprouting occurred in the control rings and 50 ng of VEGF alone was required to induce equivalent number of sprouts as NPY. SIKVAV and NPY were further tested in vivo in a rat hindlimb ischemic model. Both compounds (500 micrograms SIKVAV and 10 ng of NPY) were embedded in the rat hind limb following unilateral ligation of the femoral artery 1 cm proximal to the adductor hiatus. After two weeks control peptides show little or no revascularization of the hindlimb distal to the ligation; however, both SIKVAV and NPY demonstrated a two-fold increase in new vessels in the region proximal to the ligation. Histological sections of latex perfused hindlimb demonstrated that ligated limbs had very few latex-filled dermal capillaries. Limbs treated with SIKVAV and NPY, however, demonstrated normal distribution in the dermal capillary beds. These data indicate that both SIKVAV and NPY are potent angiogenic factors that show promising potential clinical application to the revascularization of ischemic tissue.

Grafting of PEO to glass, nitinol, and pyrolytic carbon surfaces by gamma irradiation

Glass, nitinol, and pyrolytic carbon surfaces were grafted with poly (ethylene oxide) (PEO) and PEO-containing Pluronic surfactants by gamma irradiation. These substrates were coated with a primer layer of trichlorovinylsilane (TCVS), which allows grafting of organic polymers. The TCVS-coated substrates were adsorbed with PEO or Pluronics and exposed to 0.3 Mrad of gamma radiation to graft the polymer to the surface. PEO-grafted substrates were characterized by contact angle measurement, X-ray photoelectron spectroscopy, fibrinogen adsorption, and platelet adhesion and activation. Surface modification with PEO reduced fibrinogen adsorption by as much as 99%. Platelet adhesion was significnatly reduced or prevented on the modified surfaces. Protein- and platelet-resistance effects were independent of hydrophilicity of the PEO-grafted surfaces. Polymer grafting by gamma radiation to TCVS-coated substrates provides a facile process to improve thromboresistance of inorganic biomaterials.