Chronic Coronary Artery Research Articles

Utility of established cardiovascular disease risk score models for the 10-year prediction of disease outcomes in women

Cardiovascular disease (CVD) is a major cause of mortality globally. In absolute numbers, more women die from CVD than men do. CVD mortality risk differs between genders, reflecting the different distribution of modifiable risk factors and severity of CVD outcomes. This study reviews six established risk score models and their applicability to the female population. These models are assessed against two criteria: discrimination and calibration. Sensitivity, specificity and positive- and negative-predictive values are also examined. The risk score models are found to be limited in applicability, requiring recalibration beyond their study population. Relevant risk factors to predict CVD mortality for women, such as measures of obesity, physical activity, alcohol consumption, use of antihypertensive medication, chronic kidney disease and coronary artery calcium are generally not incorporated in these models.

Percutaneous Retrograde Recanalization of a Chronic Total Coronary Artery Occlusion in a 7 Year Old

The arterial switch operation for correction of transposition of the great arteries can be complicated by late stenosis or occlusion of the coronary arteries that are re-implanted to the new aorta. We report the case of a young boy who underwent this operation as a neonate and was found to have an occluded anomalous left anterior descending artery (LAD) before age 3. Subsequent bypass surgery was complicated by anastomotic stricture and kinking of the left internal mammary artery graft to the LAD. At age 7, the LAD territory showed reversible ischemia on nuclear perfusion testing and he was referred for percutaneous coronary intervention. A combined approach with pediatric and adult interventional cardiologists resulted in successful retrograde PCI to recanalize the chronic total occlusion of the LAD. Important features of this technique in pediatric patients are discussed.

Discussing heart rate turbulence and microvolt T-wave alternans in patients after myocardial infarction: Response

We thank Dr Madias for his interest to our manuscript. In response to his question about our patient series, all consecutive patients who were admitted to our clinic due to chronic heart failure or coronary artery disease deterioration were included into the study. As for heterogeneity of the population regarding time elapsed from myocardial infarction (MI), we intentionally did not use the pre-specified time interval from the previous MI to the moment of inclusion in our study as an inclusion criterion, because we intended to analyse the possible influence of this variable on investigated parameters [microvolt T-wave alternans (mTWA) and heart rate turbulence (HRT)]. This analysis indicated that mTWA …

Endothelial progenitor cells and development of collateral formation in patients with chronic total coronary artery occlusion and transplantation of EPCs in an experimental model

Endothelial progenitor cells and development of collateral formation in patients with chronic total coronary artery occlusion and transplantation of EPCs in an experimental model

Effects of exercise therapy at the intensity of anaerobic threshold for exercise tolerance in patients with chronic stable coronary artery disease

To investigate the effects of exercise therapy at the intensity of anaerobic threshold (AT) for exercise tolerance in patients with chronic stable coronary artery disease. Forty-three patients with chronic stable coronary artery disease (3 patients after coronary arterial bypass graft (CABG) surgery, 22 patients with old myocardial infarction and 18 unstable angina pectoris undergoing successful percutaneous coronary intervention (PCI) finished twice cardiopulmonary exercise test (CPET) and followed their rehabilitation program for 3 months. Thirty-two patients finished their aerobic exercise therapy based on their individual anaerobic thresholds while 11 patients had no exercise therapy. The heart rate at AT intensity (97 ± 9/min) was lower than their traditional minimal target heart rate (112 ± 7/min) and lower than heart rate (115 ± 11/min) at ischemic threshold post-CPET. The O(2) consumption (10.7 ± 2.4 to 12.6 ± 2.9 ml×min(-1)×kg(-1)) (P = 0.04) and workload (37 ± 18 to 47 ± 13 J/s) (P = 0.04) at AT level and the O(2) consumption (15.3 ± 3.1 to 20.6 ± 4.2 ml×min(-1)×kg(-1), P = 0.02) and workload(68 ± 12 and 87 ± 14 J/s, P = 0.01) at peak level markedly increased after 3 months in the exercise group. And the O(2) consumption (15.3 ± 2.9 to 16.2 ± 3.1 ml×min(-1)×kg(-1)) and workload (65 ± 13 to 73 ± 16 J/s) at peak level mild increased after 3 months in the non-exercise group, but their O(2) consumption (11.0 ± 2.7 to 11.3 ± 2.8 ml×min(-1)×kg(-1)) and workload (38 ± 11 to 37 ± 9 J/s) at AT level had no obvious change. AT exercise intensity was lower than ischemic threshold post-CPET. Exercise therapy at the intensity of anaerobic threshold can improve oxygen capacity and exercise tolerance.

Recurrent pulmonary edema caused by chronic left main coronary artery occlusion

An 80-year-old patient was referred to our institution after three recurrent episodes of pulmonary edema, and the last one 20 days prior to the outpatient visit. The patient complained of persistent class III dyspnea, but denied chest pain. He was currently receiving aspirin, angiotensin-converting enzyme inhibitors, nitrates, amlodipine and furosemide. The past medical history included prior myocardial infarction 15 years before presentation and hypertension. The last invasive angiogram was performed 13 years before and documented an occluded left anterior descending artery and anterior wall akinesia. The …

Udrożnienia przewlekłych okluzji tętnic wieńcowych – rola wielorzędowej tomografii komputerowej.

Udrożnienia przewlekłych okluzji tętnic wieńcowych – rola wielorzędowej tomografii komputerowej.

Activation of Hypoxia-Inducible Factor by Di-Methyl Oxalyl Glycine (DMOG) Increases Neovascularization within Ischaemic Myocardium in a Porcine Coronary Artery Occlusion Model

Introduction: Chronic total coronary artery occlusion (CTO) in man remains a significant challenge for percutaneous coronary intervention (PCI) and a common reason for coronary artery bypass surgery, as often the CTO cannot be crossed. This study investigated whether a potential angiogenic treatment, the prolyl-4-hydroxylase inhibitor, di-methyl oxalyl glycine (DMOG), would increase collateral vessel formation and myocardial perfusion without opening the CTO in a porcine model of coronary CTO. Methods: We assessed the effect of DMOG upon tube formation of HUVEC in a matrigel assay in vitro. DMOG was loaded onto a polymer-coated coronary stent. Copper-coated stents were used to produce a coronary CTO in 20 pigs. DMOG-loaded or control stents were implanted in an alternating, blinded manner at day 28, proximal to the CTO. Angiographic and physiological flow data were collected at day 56, when the animals were sacrificed and the collateral vessels counted. Results: DMOG increased tubule formation in vitro by 77% compared with control (p<0.0001). DMOG was successfully loaded onto the polymer coated stent, as evidenced by the same assay. A CTO was present at angiography in all animals 28 days. At 56 days there was a trend towards a greater increase in angiographic collateral vessel area around the CTO in the DMOG group compared with controls +84.5% vs. +16.5%, respectively, p=0.057). Histology revealed a significant increase in the number of collateral vessels around the site of occlusion in the DMOG group vs control (29.9?2.6 vs 18.4?3.1, respectively; p=0.01). There was no difference between the groups in terms of collateral flow index at day 56. Conclusion: DMOG, delivered on a polymer-coated stent, proximal to an occluded porcine coronary artery, increased the number of collateral vessels seen at the site of vessel occlusion but not to a level sufficient to increase measures of functional flow.

Poor coronary collateral vessel development in patients with mild to moderate renal insufficiency

The development of coronary collaterals is crucial to survival through acute ischemia. Mild to moderate loss of renal function has been suggested to play a role in this event, but evidential data are scarce. The aim of this study was to investigate the relationship between mild to moderate renal insufficiency and coronary collateral development in patients with chronic total coronary artery occlusion. A total of 83 patients with mild to moderate loss of renal function (30mL/min/1.73m(2)≤eGFR<90mL/min/1.73m(2)) with chronic total coronary artery occlusion were included in our study. The collateral circulation was graded according to Rentrop classification and the function of collateral circulation was graded according to Werner collateral connection (CC) grades. Compared to patients with good collateral circulation (Rentrop=2,3), eGFR was found to be lower in those patients with poor coronary collateral circulation (Rentrop=0,1) (63.30±10.51 vs. 54.13±10.56, P=0.02). eGFR was also found to be lower in poorly functioning coronary collateral circulation (CC=0,1) than in efficiently functioning coronary collateral circulation (CC=2) (55.22±9.98 vs. 66.28±9.16, P=0.03). Multiple logistic regression analysis showed that low eGFR was independently associated with poor coronary collateral circulation (Rentrop=0,1, 95% CI, 0.09-1.09, P=0.044) and poor function of coronary collateral circulation (CC=0,1, 95% CI, 0.02-0.17, P=0.02). Lower eGFR is associated with poorer coronary collateral vessel development in patients experiencing mild to moderate renal insufficiency. Moreover, eGFR represents an independent factor affecting coronary collateral vessel development.

Non-invasive characterization of the area-at-risk using magnetic resonance imaging in chronic ischaemia

we investigated the performance of quantitative stress perfusion magnetic resonance imaging (MRI) as a basis for identifying and characterizing the area-at-risk subtending a chronic coronary artery (CA) stenosis. pigs underwent a percutaneous copper-coated stent implantation in the circumflex CA (n = 11) or a sham operation (n = 5). After 6 weeks, angiography and MRI were performed including cine (rest, low- and high-dose dobutamine stress), dual-bolus first-pass perfusion (rest and adenosine stress), and contrast-enhanced imaging to quantify myocardial infarction (MI). Myocardial blood flow (MBF) was quantified based on Fermi-model deconvolution and compared with microsphere measurements. On the basis of Evan's blue staining, MBF thresholds to define the area-at-risk were determined by receiver-operating characteristic (ROC) analysis. CA stenosis was 94 ± 7% and infarct size (IS) 7.3 ± 3.1% of left ventricular mass. Segmental thresholds of hyperaemic MBF yielded the best performance for detecting area-at-risk. There was a good correlation between MRI and microsphere perfusion (r(2) = 0.84, P < .0001). The area-at-risk presented a mixed substrate of non-infarcted (non-MI), <50% infarcted (MI+), and >50% infarcted (MI++) segments. MBF was reduced in at-risk vs. remote segments at rest (non-MI, 0.50 ± 0.21; MI+, 0.47 ± 0.14; MI++, 0.42 ± 0.14; remote, 0.84 ± 0.25 mL/min/g) and during stress (non-MI, 0.69 ± 0.09; MI+, 0.66 ± 0.14; MI++, 0.51 ± 0.11; remote, 1.70 ± 0.36 mL/min/g). Segmental wall thickening showed different responses to stress (remote, progressive increase during incremental stress; non-MI, increase at low-dose and discontinued at high-dose; MI+, initial increase and decrease at high-dose; MI++, progressive decrease). quantitative hyperaemic perfusion MRI accurately defines segments in the area-at-risk in chronic ischaemia, which present with different functional response to stress related to segmental IS.

104 Upregulation of hypoxia-inducible factor 1α by di-methyl oxalyl glycine promotes angiogenesis within ischaemic myocardium in a porcine coronary occlusion model

Introduction Chronic total coronary artery occlusion (CTO) remains a significant challenge for percutaneous coronary intervention (PCI), a frequent cause of angina pectoris and a common reason for referral for coronary bypass surgery. The purpose of this study was to investigate a potential alternative treatment strategy for promotion of angiogenesis and collateral blood flow. To this end we investigated the effect of the prolyl-4-hydroxylase inhibitor di-methyl oxalyl glycine (DMOG) on collateral vessel formation in an entirely endovascular porcine model of coronary occlusion. Method DMOG was loaded onto a polymer-coated coronary stent. A percutaneous model employing copper-coated stents was used to produce CTO in 20 Yorkshire white pigs. Coronary occlusions were present in all animals at 28 days. DMOG stents were implanted at day 28 and angiographic and physiological data collected on distal coronary and collateral flow. At day 56 the animals were sacrificed and histological analysis performed. Results A complete total coronary occlusion was present in all animals at day 28 following implantation of a copper stent. (Abstract 104 Figure 1) At 56 days there was a trend to a greater increase in angiographic collateral volume in the DMOG group (10±4.1 mm2 increase vs 3.6±1.5 mm 2 ; 84.5% increase vs 16.5%, p=0.057). There was no difference in collateral flow index between the groups at day 56. Histology revealed an increase in total number of collateral vessels seen around the site of occlusion in the DMOG group (29.9±2.6 vs 18.4±3.1, p=0.01) with similar distal collateral vessel density. (Abstract 104 Figure 2) Conclusions Implantation of a copper stent provides a reliable endovascular method of producing a CTO. DMOG increases the number of collateral vessels seen at the site of vessel occlusion in this endovascular model of CTO but did not increase neovascularisation in distal tissue. At baseline distal myocardium was subtended by extensive antegrade collaterals. The effect of DMOG in increasing neovascularisation appeared to be restricted to ischaemic tissue.

Physical Activity at Midlife in Relation to Successful Survival in Women at 70 Years or Older

Background: Physical activity is associated with reduced risks of chronic diseases and premature death. Whether physical activity is also associated with improved overall health among those who survive to older ages is unclear. Methods: A total of 13535 Nurses’ Health Study participantswhowerefreeofmajorchronicdiseasesatbaseline in 1986 and had survived to age 70 years or older as of the 1995-2001 period made up the study population. We defined successful survival as no history of 10 major chronic diseases or coronary artery bypass graft surgery and no cognitive impairment, physical impairment, or mental health limitations. Results: After multivariate adjustment for covariates, higher physical activity levels at midlife, as measured by metabolic-equivalent tasks, were significantly associated with better odds of successful survival. Significant increases in successful survival were observed beginning at the third quintile of activity: odds ratios (ORs) (95% confidence intervals [CIs]) in the lowest to highest quintiles were 1 [Reference], 0.98 (0.80-1.20), 1.37 (1.13-1.65), 1.34 (1.11-1.61), and 1.99 (1.66-2.38) (P.001fortrend).Increasingenergyexpenditurefrom walking was associated with a similar elevation in odds of successful survival: the ORs (95% CIs) of successful survival across quintiles of walking were 1 [Reference], 0.99(0.80-1.21),1.19(0.97-1.45),1.50(1.24-1.82),and 1.47 (1.22-1.79) (P.001 for trend). Conclusion:Thesedataprovideevidencethathigherlevels of midlife physical activity are associated with exceptional health status among women who survive to older ages and corroborate the potential role of physical activity in improving overall health. Arch Intern Med. 2010;170(2):194-201

MicroRNAs and Heart Failure Diagnosis

See related article, pages 1035–1039 Heart disease is the greatest noninfectious health hazard ever to confront the human race. It is the leading cause of death in industrialized nations, and, accordingly, it is responsible for a huge economic burden to society. It is estimated that 5 million Americans have heart failure (HF), a syndrome with mortality of approximately 50% at 5 years.1 Now, evidence indicates that the epidemic of HF is extending to the developing world. The road to advances in the treatment of HF is littered with failures, and many new means of diagnosing and tracking disease progression have disappointed. Therefore, there is an urgent need to identify novel mechanisms, markers, and therapeutic targets in HF pathogenesis. MicroRNAs (miRNAs or miRs) are among the most exciting areas in medicine and science today. MicroRNAs are endogenous, highly conserved, ≈22-nucleotide-long noncoding RNAs that regulate the stability and subsequent translation of nascent mRNA transcripts. Generally, miRs inhibit protein translation and/or promote mRNA degradation by base-pairing with 3′ untranslated regions within a transcript. MicroRNAs were first discovered in 1993 in Caenorhabditis elegans and are known to be critical to early vertebrate development and in an increasing number of basic molecular processes. Over the last few years, miRs have emerged as important mechanisms in human disease, including cardiovascular disease, diabetes, and cancer.2–6 Now, there is burgeoning interest in testing whether miRs could serve as markers for disease progression or prognostication. Indeed, in the cancer literature, strategies are emerging to use miR profiles for diagnosis and risk stratification. Currently, miR profiling is being evaluated in prostate cancer, head and neck squamous cell carcinomas, breast cancer, acute lymphoblastic leukemia, malignant mesothelioma, and other tumors.2,7–10 Most clinical studies to date on miRs have relied on tissue-based measurement of miR abundances, but miRs are …

Retrograde Angioplasty: An Option for Total Coronary Artery Occlusions

The safety and effectiveness of angioplasty for chronic total occlusions of the coronary arteries have been demonstrated in several studies, but the success rate is less than for conventional interventions. The complexity of the procedures presents a major challenge. In selected cases, performing angioplasty of the occlusion via a retrograde approach has been used as an alternative. We present the first published Spanish series, comprising 11 procedures in 9 patients, in which a retrograde approach was used to eliminate obstructions caused by chronic total coronary artery occlusions. The characteristics, outcomes and complications of the procedure were assessed.

Current considerations regarding the percutaneous revascularization of chronic total coronary occlusions

Chronic total coronary artery occlusions are commonly encountered, occurring in 15–33% of patients in the angiography suite. Reasons to consider percutaneous coronary revascularization of these lesions include the relief of angina, enhancement of left ventricular ejection fraction and the potential for improved survival. Owing to the complex nature of these lesions, attempts at percutaneous revascularization have traditionally been infrequent (≤12%of encountered cases). Advances in technique and equipment have resulted in improved success rates that now approach 90% at specialized centers. It remains to be seen if these positive results can be achieved by the interventional cardiology community at large.

Vascular restoration therapy: what should the clinical and angiographic measures for success be?

1. Revascularisation by coronary artery bypass surgery (CABG) or percutaneous coronary intervention (PCI) in conjunction with medical therapy in patients with chronic stable coronary artery disease (CAD) was associated with significantly improved survival compared with medical therapy alone (OR 0.74; 95% CI, 0.63-0.88). This benefit was seen for both revascularisation modalities, CABG and PCI separately. Revascularisation was not associated with a significant reduction in non-fatal myocardial infarction compared with medical therapy (OR 0.91; 95% CI, 0.72-1.15). Vascular restoration therapy (VRT) refers to a drug-eluting stent (DES) based percutaneous coronary revascularisation technology whose hallmark is the temporary nature of the biodegradable platform. As other percutaneous coronary revascularisation procedures, its primary goal is the relief of ischaemia by elimination of coronary luminal narrowing. The objective is achieved by temporary scaffolding of the arterial wall with concomitant release of antiproliferative agents. Both properties are required for a short period of time (3-6 months) following which biodegradation takes place with complete resolution of the device over the ensuing months and years. Assessment of endpoints must take into consideration the short- and long-term safety and efficacy of these complex implants. Clinical trials evaluating the safety and effectiveness of this novel drug-device technology play an important role in it's approval and adoption for clinical use. Although surrogate markers may have some role in the definition of device performance, direct measures of clinical outcomes are preferable in the understanding of the

Current Analysis of the Results of the COURAGE Trial

The COURAGE (Clinical Outcomes Utilizing Revascularization and Aggressive Drug Evaluation) trial was designed to evaluate the benefits of percutaneous coronary intervention in reducing the risk of cardiovascular events in patients with chronic stable coronary artery disease. The results reinforce the prior evidence regarding the importance of medical treatment which should be a universal goal. The study population enrolled was quite average for a routine cardiology clinic. However, the results of cardiac intervention are center-dependent and therefore need to be analyzed as such. Patients should initially receive the optimal medical treatment. Patients with symptom persistence, intolerance to medical treatment, and moderate to severe ischemia should be considered candidates for combined treatment. Treatment needs to be individualized and discussed with the patient. New studies, without the limitations of the COURAGE trial, enrolling high-risk patients treated with new interventional technologies, are needed to assess the impact of ischemia in long-term prognosis.

Cost-Effectiveness of Alternative Approaches to the Management of Chronic Obstructive Coronary Artery Disease

Chronic obstructive coronary artery disease (CAD) is a highly prevalent condition that results in premature mortality as well as substantial morbidity due to angina and reduced quality of life. Various treatment and revascularization strategies are available for managing this condition, including medical therapy, percutaneous coronary intervention, and coronary artery bypass grafting. These treatments are expensive and, given the high prevalence of chronic CAD, there is substantial cost involved in the management of this condition. Recent clinical trials comparing percutaneous coronary intervention with medical management and/or coronary artery bypass grafting, and their associated economic analyses, have generated new information regarding the relative value of these alternative treatment strategies. In this article, we review the basic concepts of cost-effectiveness analysis and the current evidence as it relates to the cost-effectiveness of percutaneous coronary intervention in the management of chronic obstructive coronary artery disease.

Chronic Obstructive Coronary Artery Disease

Chronic Obstructive Coronary Artery Disease

Long-term treatment strategies for atherothrombotic disease: do platelets define the course?

Atherosclerosis is a slowly progressive disease of the arteries that may undergo a sudden transition to life-threatening conditions following thrombus formation at sites of plaque disruption (atherothrombosis). Platelets play a key role in such late events. This review discusses the evidence supporting the use of oral antiplatelet agents in the long-term prevention of atherothrombotic events. In ST-elevation acute myocardial infarction and in non-ST elevation acute coronary syndromes, dual antiplatelet therapy with aspirin and clopidogrel has been proved effective in reducing death and myocardial infarction, and prolonged treatment at least up to 1 year is associated with sustained benefit. In some high-risk patients, especially in the setting of urgent percutaneous coronary interventions, adjunctive glycoprotein IIb–IIIa inhibitors confer additional benefit. In chronic coronary artery, cerebrovascular and peripheral arterial disease aspirin reduces the risk of cardiovascular events in both men and women; the adjunctive benefit of clopidogrel is questionable here. In primary prevention, the administration of aspirin is recommended only among patients at high risk.