Plasma homocysteine levels and late outcome after coronary angioplasty

Predicting long-term prognosis after percutaneous coronary intervention in patients with acute coronary syndromes: a prospective nested case-control analysis for county-level health services

Purpose

We aimed to establish and authenticate a clinical prognostic nomogram for predicting long-term Major Adverse Cardiovascular Events (MACEs) among high-risk patients who have undergone Percutaneous Coronary Intervention (PCI) in county-level health service.

Patients and methods

This prospective study included Acute Coronary Syndrome (ACS) patients treated with PCI at six county-level hospitals between September 2018 and August 2019, selected from both the original training set and external validation set. Least Absolute Shrinkage and Selection Operator (LASSO) regression techniques and logistic regression were used to assess potential risk factors and construct a risk predictive nomogram. Additionally, the potential non-linear relationships between continuous variables were tested using Restricted Cubic Splines (RCS). The performance of the nomogram was evaluated based on the Receiver Operating Characteristic (ROC) curve analysis, Calibration Curve, Decision Curve Analysis (DCA), and Clinical Impact Curve (CIC).

Results

The original training set and external validation set comprised 520 and 1,061 patients, respectively. The final nomogram was developed using nine clinical variables: Age, Killip functional classification III-IV, Hypertension, Hyperhomocysteinemia, Heart failure, Number of stents, Multivessel disease, Low-density Lipoprotein Cholesterol, and Left Ventricular Ejection Fraction. The AUC of the nomogram was 0.79 and 0.75 in the training set and external validation set, respectively. The DCA and CIC validated the clinical value of the constructed prognostic nomogram.

Conclusion

We developed and validated a prognostic nomogram for predicting the probability of 3-year MACEs in ACS patients who underwent PCI at county-level hospitals. The nomogram could provide a precise risk assessment for secondary prevention in ACS patients receiving PCI.

Association of Elevated Plasma Homocysteine Level with Restenosis and Clinical Outcomes After Percutaneous Coronary Interventions: a Systemic Review and Meta-analysis

PURPOSE

We conducted this systemic review and meta-analysis to investigate the association between elevated plasma homocysteine (Hcy) levels and recurrent restenosis and clinical outcomes after percutaneous coronary intervention (PCI).

METHODS

PubMed, EMBASE, and Web of Science were systematically searched prior to May 2018. Studies evaluating the association between plasma Hcy levels and the occurrence of restenosis, major adverse cardiac events (MACE), all-cause mortality, cardiac death, non-fatal myocardial infarction (MI), and target lesion revascularization were identified.

RESULTS

A total of 19 articles with 4340 participants were identified. Higher Hcy levels were not associated with an increased risk of restenosis (relative risk (RR) = 1.10, 95% CI 0.90-1.33). Hcy levels in the restenosis group were not significantly higher than in the non-restenosis group (weighted mean difference = 0.70, 95% CI - 0.23-1.63). Subgroup analysis revealed that higher Hcy levels were not associated with restenosis after stenting but appeared to increase the risk of restenosis after angioplasty. Elevated Hcy levels increased the risk of all-cause mortality by an average of 3.19-fold (RR = 3.19, 95% CI 1.90-5.34, P = 0.000), the risk of MACE by 1.51-fold (RR = 1.51, 95% CI 1.23-1.85, P = 0.000), and the risk of cardiac death by 2.76-fold (RR = 2.76, 95% CI 1.44-5.32, P = 0.000) but appeared not to increase the risk of non-fatal MI (RR = 1.36, 95% CI 0.89-2.09).

CONCLUSIONS

Our meta-analysis suggests that although there is no clear association between higher Hcy levels and restenosis following stent implantation, higher Hcy levels appeared to increase the risk of restenosis after coronary angioplasty and also increased the risk of all-cause mortality, MACE, and cardiac death after PCI.

REGISTRATION DETAILS

The protocol of this meta-analysis was registered on PROSPERO (CRD42018096466). ( http://www.crd.york.ac.uk/PROSPERO/display_record.php?ID=CRD42018096466 ).

Homocysteine Level Predicts Response to Dual Antiplatelet in Women With Minor Stroke or Transient Ischemic Attack: Subanalysis of the CHANCE Trial

OBJECTIVES

To investigate the relationship of homocysteine levels with the efficacy and safety of dual antiplatelet therapy in female and male patients. Approach and Results: The CHANCE trial (Clopidogrel in High-Risk Patients With Acute Nondisabling Cerebrovascular Events) randomized patients with acute minor ischemic stroke or high-risk transient ischemic attack to clopidogrel plus aspirin or aspirin alone from October 1, 2009, to July 30, 2012, in China. A subgroup of 3044 consecutive patients with baseline homocysteine levels from 73 (64%) prespecified clinical sites was analyzed. Participants were grouped by sex. Primary outcome was stroke recurrence within 90 days. Secondary outcomes consisted of composite vascular events and independent living or death. Safety outcome was any bleeding. Cox proportional-hazards models were used to assess the interaction of homocysteine levels with randomized antiplatelet therapy on efficacy and safety outcomes. A significant interaction between homocysteine levels and the randomized antiplatelet therapies was found on recurrent stroke after adjustment for confounding factors in women (P=0.010) but not in men (P=0.595). Compared with aspirin alone, clopidogrel plus aspirin significantly reduced the risk of recurrent stroke in women without elevated homocysteine levels (adjusted hazard ratio, 0.459 [95% CI, 0.271-0.776]; P=0.004). Such benefit disappeared in female patients with increased homocysteine level. No significant interaction on functional outcome or bleeding rate was observed.

CONCLUSIONS

Homocysteine could be a potential biomarker to discriminate the effects of dual and single antiplatelet therapy in female patients with minor ischemic stroke or high-risk transient ischemic attack.

CLINICAL TRIAL REGISTRATION

URL: http://www.clinicaltrials.gov. Unique identifier: NCT00979589.

Association of Hyperhomocysteinemia with Increased Coronary Microcirculatory Resistance and Poor Short-Term Prognosis of Patients with Acute Myocardial Infarction after Elective Percutaneous Coronary Intervention

Background

This study aims to investigate the coronary microcirculatory resistance and prognosis of patients with acute myocardial infarction (AMI) concomitant with hyperhomocysteinemia (HHcy) after an elective percutaneous coronary intervention (PCI).

Methods

A total of 101 patients that underwent elective PCI between May 2015 and July 2018 due to AMI were consecutively enrolled in this study. Patients were divided into a HHcy group (53) and a normal Hcy group (control; 48) based on their plasma homocysteine concentration. The characteristics of coronary angiography, the index of microcirculatory resistance (IMR) of infarct-related vessels (IRV), changes in left ventricular end diastolic diameter (LVEDd) and left ventricular ejection fraction (LVEF) before and after PCI, and the incidence of major adverse cardiovascular events (MACE) three months after PCI were compared between these groups.

Results

Compared to the results from the Hcy group, the HHcy group had a higher IMR. The HHcy group had significantly higher LVEDd and a lower LVEF than the Hcy group 3 months after PCI. Additionally, the incidence of MACE at three months after PCI was higher in the HHcy group than in the Hcy group. Pearson correlation analysis revealed a positive correlation with IMR in the HHcy group. Furthermore, there was a difference in the LVEDd measured at one day after PCI and at three months after PCI in the HHcy group.

Conclusion

AMI patients concomitant with HHcy that undergo elective PCI are prone to coronary microcirculatory dysfunction and have a poor cardiac function and poor prognosis at three months after PCI.

Impact of Homocysteine Level on Long-term Cardiovascular Outcomes in Patients after Coronary Artery Stenting

Aim: The prognostic value of homocysteine (HCY) in patients with coronary artery diseases (CAD) is still controversial. The objective of this study was to investigate whether elevated HCY level at admission predict long-term outcomes in patients after percutaneous coronary interventions (PCI) with coronary artery stenting.

Methods: From the institutional registry of Cardiovascular Atherosclerosis and Percutaneous TrAnsluminal INterventions (CAPTAIN), we enrolled a total of 1,307 patients with documented CAD undergone PCI with bare metal stents from July 2003 to December 2014. They were divided into two groups according to the fasting plasma HCY levels before catheterization: group I (883 patients, < 12 µmol/L) and group II (424 patients, ≥ 12 µmol/L). The primary endpoint was occurrence of major adverse cardiac events (MACE), including cardiac death, nonfatal myocardial infarction, stroke, target lesion revascularization, new lesion stenting, and requiring bypass surgery.

Results: After a mean follow-up period of 58 ± 41 months, the group II patients had a higher MACE rate (33.3% vs. 25.6%, p = 0.005). The main differences between two groups were cardiac death (8.0% vs. 3.4%, p = 0.001) and new lesion stenting (13.6% vs. 9.5%, p = 0.034). The risks of long-term MACE remained significantly higher in patients with elevated HCY level (≥ 12 µmol/L) after adjusting for clinical variables, with a hazard ratio of 1.29 (95% CI, 1.02–1.64, p = 0.036).

Conclusions: Elevated HCY level (≥ 12 µmol/L) was independently associated with increased risk of long-term cardiovascular events in patients after coronary artery bare metal stents implantations. Thus, hyperhomocysteinemia may remain a useful prognostic marker for the risk assessment in clinical care of CAD patients.

Homocysteine is associated with the progression of non-culprit coronary lesions in elderly acute coronary syndrome patients after percutaneous coronary intervention

BACKGROUND

The influence of homocysteine (Hcy) on the migration and proliferation of vascular smooth muscle cells has been well established. However, the impact of Hcy levels on the progression of non-culprit coronary lesions (NCCLs) is controversial. This study aims to evaluate whether the plasma level of Hcy is related to the progression of NCCLs after percutaneous coronary stent implantation in elderly patients with acute coronary syndrome (ACS).

METHODS

A total of 223 elderly patients (≥ 65 years old) with ACS undergoing stent implantation and follow-up coronary angiography were enrolled. Laboratory determination comprised of blood sample evaluation for Hcy was carried out before baseline coronary intervention. The patients were classified into two groups according to the blood Hcy tertiles (≥ 15 mmol/L or < 15 mmol/L). Patients were followed up for 12.2 months. NCCL progression was assessed by three-dimensional quantitative coronary angiography.

RESULTS

A significantly higher ratio of NCCL progression was observed in the group with baseline Hcy concentrations above 15 mmol/L compared to the group with concentrations below 15 mmol/L (41/127, 32.3% vs. 14/96, 14.6%, P = 0.002). Multivariate Cox regression analysis showed that Hcy and diabetes mellitus were independent risk factors for NCCL progression. The crude hazard ratio (HR) of NCCL progression for Hcy level was 1.056 (95% CI: 1.01-1.104, P = 0.015). The adjusted HR of NCCL progression for Hcy level was 1.024 (95% CI: 1.007-1.042, P = 0.007). The adjusted HR of NCCL progression for diabetes mellitus was 1.992 (95% CI: 1.15-3.44, P = 0.013).

CONCLUSIONS

Hcy is an independent risk factor for NCCL progression after 12 months of follow-up in elderly patients with ACS who has undergone percutaneous coronary stenting.

Serum biomarkers and the prognosis of AMI patients

BACKGROUND

It has been proven that serum lactate dehydrogenase (LDH) and total bilirubin (TB) increase during acute myocardial infarction (AMI). However, how they influence the prognosis of AMI patients is still not completely known.

METHODS

A total of 239 patients diagnosed with AMI and admitted to the Fourth Clinical Hospital of Harbin Medical University, between 2007 and 2008, were enrolled in this study. All the patients had not undergone primary percutaneous coronary intervention (PCI) because the time window (24 h) was missed. They all underwent PCI 1 week after the onset of symptoms. Serum high-sensitivity C-reactive protein (hs-CRP), TB, LDH, and other biomarkers were determined between 24 and 48 h of symptom onset. All of the patients were followed up for an average of 3.2±0.4 years for occurrence of major adverse cardiac events (MACE).

RESULTS

Patients with MACE had significantly higher levels of hs-CRP, LDH, cystatin C, uric acid, a higher ratio of LDH and TB (LDH/TB), and a lower level of TB: 8.48±3.84 vs. 2.13±1.32 μmol/l, p<0.01; 1,355.8±654.3 vs. 1,151.7±415.4 U/l, p<0.01; 1.69±0.76 vs. 1.00±0.46 mg/l, p<0.01; 419.6±109.2 vs. 343.2±108.2 μmol/l, p<0.01 and 141.1±46.2 vs. 61.2±26.5, p<0.01; 18.3±6.7 vs. 14.8±6.6 mg/l, p<0.01, respectively. In the multivariate COX analysis, LDH, cystatin C, and LDH/TB were significantly associated with the prognosis of these patients.

CONCLUSIONS

Patients under higher oxidative stress tend to have more MACE. LDH, cystatin C, and LDH/TB are strongly related to the prognosis of AMI patients undergoing elective PCI.

Effects of ghrelin on homocysteine-induced dysfunction and inflammatory response in rat cardiac microvascular endothelial cells

Ghrelin is a well-characterized hormone that has protective effects on endothelial cells. Elevated HCY (homocysteine) can be a cardiovascular risk factor, but it is not known whether ghrelin can inhibit HCY-induced dysfunction and inflammatory response in rat CMECs (cardiac microvascular endothelial cells). We found that HCY treatment for 24 h inhibited proliferation and NO (nitric oxide) secretion, but with increased cell apoptosis and secretion of cytokines in CMECs. In contrast, ghrelin pretreatment significantly improved proliferation and NO secretion, and inhibited cell apoptosis and secretion of cytokines in HCY-induced CMECs. In addition, Western blot assay showed that NF-κB (nuclear factor κB) and cleaved-caspase 3 expression were elevated, and PCNA (proliferating cell nuclear antigen) and eNOS (endothelial nitric oxide synthase) expression were decreased after treatment with HCY, which was significantly reversed by pretreatment with ghrelin. The data suggest that ghrelin inhibits HCY-induced CMEC dysfunction and inflammatory response, probably mediated by inhibition of NF-κB activation.

Alternative prevention and treatment of cardiovascular disease, part 2

This article discusses alternative therapies for secondary prevention and treatment of major cardiac disorders: congestive heart failure, hypertension, dyslipidemias, and peripheral vascular disease. The role of various therapies (eg, herbal and botanic preparations, supplements, mind/body interventions, other alternative modalities of care) are addressed relative to each disease state and will hopefully give the practitioner or student a readily accessible suite of integrative therapies for common cardiac illnesses.

Promises and Problems of Functional Foods

"Functional" foods are branded foods, which claim, explicitly or implicitly, to improve health or well being. We review typical functional foods and their ingredients, efficacy, and safety. We also review regulations for health claims for foods worldwide. These regulations often allow manufacturers to imply that a food promotes health without providing proper scientific evidence. At the same time, regulations may ban claims that a food prevents disease, even when it does. We offer a plea for regulations that will permit all health claims that are supported by the totality of scientific evidence, and ban all claims that suggest an unproven benefit.

Cysteine: a potential biomarker for obstructive sleep apnea

OBJECTIVE

Obstructive sleep apnea (OSA) is a risk factor for a number of cardiovascular conditions. Although homocysteine (Hcy) and cysteine (Cys) are regarded as cardiovascular risk factors, few studies have analyzed Hcy and Cys plasma concentrations in patients with OSA. The aim of this study was to evaluate the role of Hcy and Cys in OSA in comparison with subjects without OSA and to determine the possible influence of obesity on these variables.

METHODS

Patients who submitted to polysomnography studies were recruited to engage in an 8-h fasting period for blood sample withdrawal, physical examination, ECG, and echocardiogram. A subgroup of lean patients with OSA (BMI < 25 kg/m(2)) were analyzed to rule out the influence of obesity. Fifteen patients were randomly assigned to participate in a continuous positive airway pressure (CPAP) protocol to assess the influence of OSA treatment on the obtained measurements.

RESULTS

A total of 75 patients and 75 control subjects matched for age and sex were analyzed. The Cys plasma levels were higher in patients with OSA compared with control subjects (490.16 ± 67.00 μmol/L vs 439.81 ± 76.12 μmol/L, respectively, P < .01); however, the Hcy plasma levels did not differ between groups. Cys plasma levels were also higher in the OSA lean subgroup when compared with lean control subjects (484.21 ± 71.99 μmol/L vs 412.01 ± 70.73 μmol/L, respectively, P = .009). There was a significant decrease of Cys plasma levels after 6 months of CPAP effective therapy.

CONCLUSION

Cys is a potential biomarker of OSA in obese and nonobese patients and is reduced after effective OSA treatment.

Plasma homocysteine level and left ventricular thrombus formation in acute anterior myocardial infarction patients following thrombolytic therapy with t-PA

AIMS

The aim of this study was to evaluate the relationship between homocysteine levels and the development of left ventricular thrombus in acute anterior myocardial infarction patients directed to thrombolytic therapy.

METHODS AND RESULTS

Seventy-nine patients presenting with ST elevated acute anterior myocardial infarction and treated with thrombolytic agent, t-PA, were included in the study. Two-dimensional echocardiography was used to divide patients into 2 groups according to the presence (n = 14) or absence (n = 65) of thrombus in the left ventricle following myocardial infarction. The levels of fasting plasma total homocysteine, total cholesterol, triglycerides, HDL-cholesterol, LDL-cholesterol, vitamin B12 and folic acid were assessed. There were no significant differences between two groups in terms of age, gender, hyperlipidemia and smoking. History of diabetes mellitus (28.57% versus 6.15%, p = 0.04), peak creatine phosphokinase levels (4153.54 +/- 1228.41 U/L versus 2456.92 +/- 1421.36 U/L, p < 0.001), mean left ventricular wall motion score index (2.21 +/- 0.18 versus 1.83 +/- 0.23, p < 0.001) and total fasting homocysteine levels (18.24 +/- 5.67 mmol/L versus 12.31 +/- 3.52 mmol/L, p < 0.001) were significantly higher in patients with left ventricular thrombus. In multivariate analysis; only diabetes mellitus (p = 0.03), higher wall motion score index (p = 0.001) and higher homocysteine levels (p = 0.04) were independent predictors of left ventricular thrombus formation.

CONCLUSION

Our results suggest that; diabetes mellitus, higher wall motion score index and hyperhomocysteinemia independently increases the risk for the development of left ventricular thrombus formation in patients with acute anterior myocardial infarction following thrombolytic therapy.

Hyperhomocysteinemia and recurrent carotid stenosis

BACKGROUND

Hyperhomocysteinemia has been identified as a potential risk for atherosclerotic disease in epidemiologic studies. This study investigates the impact of elevated serum homocysteine on restenosis after carotid endarterectomy (CEA).

METHODS

In a retrospective study, we compared fasting plasma homocysteine levels of 51 patients who developed restenosis during an eight year period after CEA with 45 patients who did not develop restenosis. Restenosis was defined as at least 50% stenosis and was assessed by applying a routine duplex scan follow up investigation. Patients with restenosis were divided into a group with early restenosis (between 3 and 18 months postoperative, a total of 39 patients) and late restenosis (19 and more months; a total of 12 patients).

RESULTS

The groups were controlled for age, sex, and risk factors such as diabetes, nicotine abuse, weight, hypertension, and hyperlipidemia. Patients with restenosis had a significant lower mean homocysteine level (9.11 micromol/L; range: 3.23 micromol/L to 26.49 micromol/L) compared to patients without restenosis (11.01 miccromol/L; range: 5.09 micromol/L to 23.29 micromol/L; p = 0.03). Mean homocysteine level in patients with early restenosis was 8.88 micromol/L (range: 3.23-26.49 micromol/L) and 9.86 micromol/L (range 4.44-19.06 micromol/L) in late restenosis (p = 0.50).

CONCLUSION

The finding suggests that high plasma homocysteine concentrations do not play a significant role in the development of restenosis following CEA.

Cardiovascular and thrombophilic risk factors in patients with retinal artery occlusion

This article evaluates the prevalence of cardiovascular and thrombophilic risk factors in patients with retinal artery occlusion. Forty-one patients with a first episode of a retinal artery occlusion underwent complete ophthalmic examination, routine blood testing and specific laboratory tests for thrombophilia, such as fasting and postmethionine homocysteine, lipoprotein(a), plasminogen activator inhibitor-1, factor VIII, factor V Leiden, factor II G20210A polymorphism, lupus anticoagulant and anticardiolipin antibodies. The control population consisted of 100 healthy individuals comparable as regards age and sex. At univariate analysis, hypertension, smoking, dyslipidaemia (both high cholesterol and triglyceride levels), antiphospholipid antibodies, hyperhomocysteinaemia, elevated factor VIII and lipoprotein(a) levels were significantly associated with retinal artery occlusion; at multivariate analysis, adjusted for age, sex, traditional and thrombophilic risk factors, smoking, hypercholesterolaemia, elevated homocysteine and lipoprotein(a) levels confirmed their independent role as risk factors for retinal artery occlusion. In conclusion, the results of the present pilot study demonstrate that the prevalence of hypercholesterolaemia and smoking and the 'thrombophilic burden' are increased in patients with retinal artery occlusion. Our findings may have implications for the management of these patients, suggesting the need for an intensive and tailored secondary prevention and new therapeutic approaches.

B-vitamins, homocysteine metabolism and CVD

The present review focuses on the B-vitamins, i.e. folate, vitamin B12, vitamin B6and riboflavin, that are involved in homocysteine metabolism. Homocysteine is a S-containing amino acid and its plasma concentrations can be raised by various constitutive, genetic and lifestyle factors, by inadequate nutrient status and as a result of systemic disease and various drugs. Hyperhomocysteinaemia is a modest independent predictor of CVD and stroke, but causality and the precise pathophysiological mechanism(s) of homocysteine action remain unproven. The predominant nutritional cause of raised plasma homocysteine in most healthy populations is folate insufficiency. Vitamin B12and, to a lesser extent, vitamin B6are also effective at lowering plasma homocysteine, especially after homocysteine lowering by folic acid in those individuals presenting with raised plasma homocysteine. However, riboflavin supplementation appears to be effective at lowering plasma homocysteine only in those individuals homozygous for the T allele of the C677 T polymorphism of the methylenetetrahydrofolate reductase (MTHFR) gene. This gene codes for the MTHFR enzyme that produces methyltetrahydrofolate, which, in turn, is a substrate for the remethylation of homocysteine by the vitamin B12-dependent enzyme methionine synthase. Individuals with the MTHFR 677 TT genotype are genetically predisposed to elevated plasma homocysteine, and in most populations have a markedly higher risk of CVD.

Low plasma glutathione levels after reperfused acute myocardial infarction are associated with late cardiac events

OBJECTIVE

To clarify whether an altered redox state persists in the subacute phase of myocardial infarction and if specific redox patterns are associated with later cardiac events.

METHODS

Ninety-seven patients [80 men, median 63 (interquartile range, 53, 69) years] with a first acute myocardial infarction, with (53%) or without ST segment elevation, treated with successful percutaneous interventions, were tested at 5-6 days after admission for plasma alpha-tocopherol, ascorbic acid, total and reduced homocysteine, cysteine, glutathione, cysteinylglycine and blood-reduced glutathione, all assessed by high-pressure liquid chromatography. Free malondialdehyde was evaluated by gas chromatography. A subgroup of 14 patients had adjunctive blood samples within 1 h and at 72 h after angioplasty. Blood samples from 44 patients matched for age, sex, and risk factors served as controls. Patients were followed up for median 15 (interquartile range, 9, 17) months for cardiac events.

RESULTS

All plasma-reduced aminothiols, vitamins and plasma total glutathione were significantly lower in myocardial infarction at 5-6 days than in controls. In the 14 myocardial infarction patients sampled repeatedly, plasma-reduced glutathione, cysteinylglycine, total glutathione, and alpha-tocopherol significantly decreased, whereas blood-reduced glutathione, total homocysteine, and cysteine significantly increased over time. During follow-up, 20 of 97 (21%) patients had adverse cardiac events. Multivariate analysis revealed that only plasma-reduced glutathione was independently associated with events (hazard ratio 0.42, 95% confidence interval 0.18-0.99, P=0.04).

CONCLUSIONS

Acute myocardial infarction patients have an altered redox state at 5-6 days after successful reperfusion with respect to controls. Low plasma levels of reduced glutathione at discharge are associated with cardiac events at follow-up.

Homocysteine and vitamin B(12) concentrations and mortality rates in type 2 diabetes

OBJECTIVE

To assess the role of homocysteine as a risk factor for mortality in diabetic subjects.

METHODS

Homocysteine, vitamin B(12), and folate concentrations were measured in stored sera of 396 diabetic Pima Indians aged > or = 40 years when examined between 1982 and 1985. Vital status was assessed through 2001.

RESULTS AND CONCLUSIONS

Over a median follow-up of 15.7 years, there were 221 deaths-76 were due to cardiovascular disease (CVD), 36 to diabetes/nephropathy and 34 to infections. Homocysteine was positively associated with mortality from all causes (hazard rate ratio (HRR) for highest versus lowest tertile of homocysteine = 1.70, 95% confidence interval (CI) 1.18-2.46), from diabetes/nephropathy (HRR = 2.39, 95% CI 0.94-6.11) and from infectious diseases (HRR = 3.39, 95% CI 1.19-9.70), but not from CVD (HRR = 1.16, 95% CI 0.62-2.17) after adjustment for age, sex and diabetes duration. Homocysteine correlated with serum creatinine (r = 0.50), and the relationships with mortality rates were not significant after adjustment for creatinine. Vitamin B(12) was positively associated with all-cause mortality (HRR for 100 pg/mL difference adjusted for age, sex and diabetes duration = 1.15, 95% CI 1.08-1.22) and death from diabetes/nephropathy (HRR = 1.27, 95% CI 1.10-1.46). The association between homocysteine and mortality in type 2 diabetes is not causal, but is confounded by renal disease in Pima Indians.

Plasma homocysteine levels and late outcome in patients with unstable angina

AIM OF THE STUDY

Previous studies have suggested that total plasma homocysteine (HCY) is an important cardiovascular risk factor because of its interaction with vascular smooth muscle cells, endothelium function, plasma lipoprotein, coagulation factors and platelets. The aim of this study was to evaluate a possible relationship between HCY levels and the severity of coronary artery disease (CAD) and its prognostic value in patients with unstable angina (UA).

METHODS AND RESULTS

Ninety-four patients with UA were recruited and underwent coronary angiography and in some cases myocardial revascularization. The primary end point was the severity of CAD. The clinical end points were the recurrence of UA and the compositive end point of the occurrence of cardiac death and re-hospitalization due to acute coronary syndrome. HCY levels were shown to be poorly correlated with the severity of CAD. After 48 months' of follow-up, a graded relationship between HCY levels and recurrence of UA and compositive end point was found (p < 0.001).

CONCLUSIONS

In the light of events occurring during the follow-up period, it was concluded that total plasma HCY is a strong predictor of recurrence of UA.

Methods of detecting atherosclerosis in non-cardiac surgical patients; the role of biochemical markers

Atherosclerosis is a common condition in both the developed and developing world and is now recognised to be an inflammatory condition leading to the development of ischaemic heart disease, cerebrovascular disease and peripheral vascular disease. Ischaemic heart disease is a major risk factor in the pathogenesis of perioperative adverse cardiovascular events which lead to significant morbidity and mortality within the high risk surgical patient population. Current methods of evaluating the likelihood of postoperative cardiovascular complications depend largely on risk scoring systems, and the preoperative assessment of the functional status of the cardiovascular system. However, the possible role of inflammation in the generation of atherosclerosis has led to the identification of several biochemical markers such as acute phase proteins, cellular adhesion molecules and cytokines. An alternative approach therefore is the measurement of preoperative levels of these biomarkers with the aim of assessing pre-existing disease activity. This review summarises the pathophysiology of atherosclerosis and perioperative myocardial infarction, and discusses the possible future role of biomarkers in the risk stratification of patients undergoing non-cardiac surgery.

Total homocysteine concentration and associated cardiovascular and renal implications in adults

Hyperhomocysteinemia has been linked to an increased risk for cardiovascular (CV) disease since 1969. Recent epidemiological and cohort observations continue to confirm this relationship, provided the homocysteine concentration is elevated. This elevation in homocysteine concentration and increased CV disease risk are particularly strong in patients with renal disease. Hyperhomocysteinemia is also related to declining status of vitamins B6 and B12, folate, and in some cases riboflavin. This relationship between vitamins and homocysteine concentration has provided the basis for clinical trials targeting CV risk reduction by vitamin supplementation. This review describes the evidence behind vitamin supplementation as it pertains to homocysteine status and make recommendations for vitamin intake management in patients with hyperhomocysteinemia, including those patients with renal disease.

Postinterventional homocysteine levels: Failure as a predictive biomarker of in-stent restenosis

OBJECTIVES

Purpose of our study was to determine if homocysteine plasma levels are related to the risk of in-stent restenosis after percutaneous coronary stent implantation in de novo lesions.

BACKGROUND

The putative role of homocysteine as a predictive cardiovascular biomarker of coronary artery disease is well established. The impact of homocysteine levels in the development of in-stent restenosis, however, is controversially discussed.

METHODS

A total of 177 patients with stable angina pectoris undergoing stent implantation in coronary de novo lesions were included. Laboratory determination comprised blood sample evaluation for homocysteine and other conventional risk factors before baseline coronary intervention and prior to six months control catheterization. Binary restenosis, late lumen loss, and late loss index after six months were assessed by quantitative coronary angiography. Endpoints included target lesion and target vessel failure, homocysteine levels as well as major adverse cardiac events.

RESULTS

There was a significant correlation between the length of the implanted stent (p<0.006), the percentage of stenosis (p<0.003) and the pre-interventional luminal diameter (p<0.0001) with late loss index. Linear regression analysis demonstrated no significant impact of the initial or six months homocysteine levels on angiographic restenosis, late lumen loss, or late loss index.

CONCLUSIONS

In contrast to homocysteine levels, luminal diameter, stent length and percentage of stenosis correlated with the appearance of restenosis. Taking our data into consideration, we hypothesise that homocysteine may not serve as a safe and independent biomarker of in-stent restenosis after a six months period following percutaneous coronary stenting.

Plasma homocysteine levels and the left ventricular systolic function in coronary artery disease patients

BACKGROUND

Numerous studies have shown a relationship between hyperhomocysteinemia, atherothrombosis and cardiovascular mortality. However, an association between hyperhomocysteinemia and the extent of coronary artery disease (CAD) remains controversial whereas its relationship with left ventricular systolic function has not been established.

METHODS

One hundred and fifty-seven patients with angiographically defined CAD were included. The relationships between hyperhomocysteinemia, severity of CAD and left ventricular systolic function were studied. Left ventricular systolic function was determined primarily by ventriculography. The severity of CAD was determined through coronary angiography using the Gensini score and the number of vessels with > or = 50% stenosis.

RESULTS

The mean fasting plasma homocysteine level was 13.4 mumol/l+/-0.5 SE. Elevated levels of homocysteine correlated significantly with increased severity of CAD both by the Gensini scores (r-value = 0.344, P < 0.0005) and the total number of diseased vessels (r-value = 0.387, P < 0.0005). The patients with hyperhomocysteinemia were found to have significantly reduced left ventricular ejection fraction (r-value = -0.382, P < 0.0005). A multivariate regression analysis revealed homocysteine level to be an independent predictor of left ventricular systolic function. In addition, adjusted analysis revealed hyperhomocysteinemia to be associated with global left ventricular dysfunction.

CONCLUSION

In patients with CAD, homocysteine levels correlate independently with left ventricular systolic function. The mechanism of this association between homocysteine and left ventricular systolic function is unknown but may be due to a direct effect of homocysteine on myocardial function separate from its effects on coronary atherosclerosis.

Risk stratification in non-ST elevation acute coronary syndromes: predictive power of troponin I, C-reactive protein, fibrinogen and homocysteine

INTRODUCTION

In acute coronary syndromes, myocardial damage markers and acute-phase reactants predict adverse cardiac events. The aim of this study was to define the fitted prognostic value of the most widely used variables of necrosis and inflammation as well as of homocysteine.

METHODS AND RESULTS

Troponin I, high-sensitivity C-reactive protein, fibrinogen and homocysteine were measured in 515 consecutive patients admitted to our institution for non-ST elevation acute coronary syndrome. The risk for major events (death or nonfatal myocardial infarction) through 6 months of follow-up was analysed. In the univariate analysis, all markers were related to major events (p<0.01 in all cases). In a multivariate model fitting for baseline characteristics and electrocardiographic changes, the only biomarkers related to major events were C-reactive protein >11 mg/l (2.1 [1.2-3.8] p=0.007) and troponin I >3 ng/ml (1.9 [1.1-3.4] p=0.03). Moreover, the rate of major events was significantly higher (p<0.0001) only when both C-reactive protein and troponin I were increased (31.4% vs. 9.3% if any or both markers were normal).

CONCLUSION

In non-ST elevation acute coronary syndromes elevated levels of troponin I, C-reactive protein, fibrinogen and homocysteine are strongly related to the risk of major events. The prognostic value of troponin I and C-reactive protein is independent and additive with respect to each other.

Multimarker risk strategy for predicting 1-month and 1-year major events in non-ST-elevation acute coronary syndromes

BACKGROUND

The aim of this study was to define the utility of the combined measurement of troponin I, myoglobin, C-reactive protein, fibrinogen, and homocysteine to predict risk in non-ST elevation acute coronary syndromes.

METHODS

Troponin I, myoglobin, high-sensitivity C-reactive protein, fibrinogen, and homocysteine were measured in 557 consecutive patients admitted to our institution for non-ST elevation acute coronary syndrome. The risk for major events (death or nonfatal myocardial infarction) at first month and at first year follow-up was analyzed.

RESULTS

In a multivariate model adjusting for baseline characteristics and electrocardiographic changes, the only biomarkers related to major events at first month were C-reactive protein (P = .007) and myoglobin (P = .02), and at first year troponin I (P = .02), C-reactive protein (P = .03), and homocysteine (P = .04). The rate of major events depending on the number (0-5) of elevated biomarkers were at first month: 4.1%, 3.7%, 5.7%, 6.1%, 6.5%, and 30.8% (P < .0001), and at first year: 8.2%, 11.1%, 12.3%, 16.2%, 23.7%, and 50% (P < .0001). A simple score including the number of elevated biomarkers showed an adjusted risk of major events of 1.6 [1.3-1.9] at first month and of 1.4 [1.2-1.7] at first year.

CONCLUSIONS

Markers of myocardial damage, inflammation, and homocysteine analyzed separately provide prognostic information. The number of elevated biomarkers is an independent risk predictor of major events.

Relevance of post-methionine homocysteine and lipoprotein (a) in evaluating the cardiovascular risk in young CAD patients

BACKGROUND

Aims of our study were to evaluate the prevalence of high lipoprotein (a) [Lp(a)] and homocysteine levels - both in the fasting state (FHcy) and post-methionine (PMHcy) - in young coronary artery disease (CAD) patients, and to investigate the role of genetic and environmental factors for hyperhomocysteinaemia.

MATERIALS AND METHODS

We studied 140 patients with angiographically documented CAD (24 women </= 55 years and 116 men </= 50 years) and 140 healthy subjects as controls.

RESULTS

Both FHcy [13.2 (5.4-45.8) vs. 9.0 (5.1-24) micromol L(-1)); P < 0.0001] and PMHcy [(39.4 (9.0-66.4) vs. 25.2 (16.4-33.9); P < 0.0001] were significantly higher in patients than in controls. Lp(a) levels were significantly higher in patients than in controls (200 (3-1486) mg L(-1) vs. 97 (10-412) mg L(-1); P < 0.0001). At the multivariate analysis, adjusted for the classical cardiovascular risk factors and creatinine levels, the OR (95% CI) for CAD at young age significantly increased in the fourth quartile of the distribution of FHcy, PMHcy and Lp(a) levels [FHcy: 14.9 (4.1-58), P < 0.0001; PMHcy: 19.2 (4.0-86.3); P < 0.0001; Lp(a): 19.6 (4.7-78.6): < 0.0001]. Vitamin deficiencies were detected in 28/140 (20%) patients. The prevalence of the homozygous C677T (+/+) methylenetetrahydrofolatereductase genotype was higher, but not significantly different, in patients (22.8%) than in controls (18.6%). The allele frequency of the 844ins68 insertion variant in the cystathionine beta-synthase gene was 0.08 in the control group and 0.06 in the patient group.

CONCLUSIONS

Results of the present study indicate the usefulness of including fasting and post-methionine Hcy, and Lp(a) determination in the diagnostic panels of young CAD patients, in order to obtain a better assessment of their cardiovascular risk profile.

Risk factors for atherosclerotic vascular disease

Several controlled interventional trials have shown the benefit of anti-hypertensive and hypolipidaemic drugs for the prevention of coronary heart disease (CHD). International guidelines for the prevention of CHD agree in their recommendations for tertiary prevention and recommend lowering the blood pressure to below 140 mm/90 mm Hg and low density lipoprotein (LDL)-cholesterol to below 2.6 mmol/l in patients with manifest CHD. Novel recommendations for secondary prevention are focused on the treatment of the pre-symptomatic high-risk patient with an estimated CHD morbidity risk of higher than 20% per 10 years or an estimated CHD mortality risk of higher than 5% per 10 years. For the calculation of this risk, the physician must record the following risk factors: sex, age, family history of premature myocardial infarction, smoking, diabetes, blood pressure, total cholesterol, LDL-cholesterol, high-density lipoprotein (HDL)-cholesterol, and triglyceride. This information allows the absolute risk of myocardial infarction to be computed by using scores or algorithms which have been deduced from results of epidemiological studies. To improve risk prediction and to identify new targets for intervention, novel risk factors are sought. High plasma levels of C-reactive protein has been shown to improve the prognostic value of global risk estimates obtained by the combination of conventional risk factors and may influence treatment decisions in patients with intermediate global cardiovascular risk (CHD morbidity risk of 10%-20% per 10 years or CHD mortality risk of 2%-5% per 10 years).

[Independent role of C reactive protein to predict major events at one-month and at one-year in acute coronary syndrome without ST elevation]

BACKGROUND AND OBJECTIVE

We intended to determine whether C-reactive protein (CRP) provides independent prognostic information after a non-ST elevation acute coronary syndrome.

PATIENTS AND METHOD

We prospectively studied 630 consecutive patients admitted with a diagnosis of non-ST elevation acute coronary syndrome. Cut-off values were: troponin I > 1 ng/ml (n = 354; 56%) and CRP > 11 mg/l (n = 273; 43%).

RESULTS

Within a one-year follow-up period, 56 (9%) cardiac deaths, 85 (13%) myocardial infarctions (MI) and 127 (20%) first major events were detected. Patients with increased CRP showed higher rates of death at one-month (8% vs 1%), death at one-year (15% vs 4%), myocardial infarction at one-month (8% vs 4%), myocardial infarction at one-year (19% vs 9%), major events at one-month (15% vs 5%) and major events at one-year (30% vs 13%). In the multivariate analysis, once adjusted for baseline and electrocardiogram data and for myocardial damage markers, CRP was an independent predictor of death at one-month (odds ratio [OR] 4.6) and death at one-year (OR = 2.7), major events at one-month (OR = 1.8) and major events at one-year (OR = 1.8). Troponin I predicted MI at one-month (OR = 2.5) and MI at one-year (OR = 2.2).

CONCLUSIONS

CRP provided independent information to predict major events in non-ST elevation acute coronary syndromes. Troponin I was a more powerful predictor of MI than PCR. The analysis of CRP and myocardial damage markers in the short-term and long-term risk stratification seems worthy.

Effect of folic acid fortification of food on homocysteine-related mortality

PURPOSE

In 1998, the Food and Drug Administration mandated the fortification of food products with folic acid. The effect of this rule on mortality associated with homocysteine levels in patients with coronary artery disease is unknown.

METHODS

We studied 2481 consecutive patients with coronary artery disease who underwent coronary angiography between 1994 and 1999, and who had baseline homocysteine measurements and at least 2 years of follow-up. Patients were divided into prefortification (1994 to 1997, n = 1595) and postfortification (1998 to 1999, n = 886) groups, as well as classified based on baseline homocysteine levels (normal to low, intermediate, and high). Homocysteine levels were measured by fluorescence polarization immunoassay. Mortality was determined by telephone survey or from a national Social Security database or hospital records.

RESULTS

After implementation of the fortification rule, median homocysteine levels declined from 13.8 to 12.3 micromol/L (P <0.001), and the proportion of patients with high homocysteine levels (>15 micromol/L) decreased from 41% (n = 650) to 28% (n = 249) (P <0.001). Overall, homocysteine was a modest risk factor for mortality (adjusted relative risk [RR] = 1.03 per micromol/L; 95% confidence interval [CI]: 1.01 to 1.05; P = 0.006). There was no significant interaction between fortification status and homocysteine category with mortality (P for interaction = 0.85). Two-year mortality was reduced minimally (7.8% [n = 124] to 7.2% [n = 64]; RR = 0.93; 95% CI: 0.68 to 1.27; P = 0.63; adjusted RR = 0.97; 95% CI: 0.68 to 1.40), but was consistent with the expectation of a modest reduction in homocysteine levels.

CONCLUSION

Homocysteine is an independent, graded risk factor for mortality. Homocysteine levels decreased modestly after the fortification of food with folic acid, but the effects on mortality were minor and likely attributable to other factors, indicating the need for more aggressive measures to reduce homocysteine-associated cardiovascular risk.

Homocysteine Status and Polymorphisms of Methylenetetrahydrofolate Reductase Are Not Associated With Restenosis After Stenting in Coronary Arteries

Objective— We investigated the influence of elevated homocysteine plasma levels and 2 polymorphisms, 677C/T and 1298A/C, of the methylenetetrahydrofolate reductase (MTHFR) gene on the risk of restenosis after stenting in patients with symptomatic coronary artery disease.

Methods and Results— Homocysteine levels and MTHFR genotypes were determined in 800 consecutive patients treated with coronary artery stenting. Angiographic restenosis (≥50% diameter stenosis at 6-month follow-up) was present in 25.8% of the patients with low homocysteine levels (at or below the median of 11.6 μmol/L; n=400) and 24.1% of the patients with high homocysteine levels (>11.6 μmol/L; n=400; P =0.62). Rates of angiographic restenosis were 26.0%, 23.5%, and 26.9% in carriers of the 677CC, 677CT, and 677TT genotypes ( P =0.75), respectively, and 24.4%, 25.9%, and 24.0% in patients with the 1298AA, 1298AC, and 1298CC genotypes ( P =0.90), respectively. The need for restenosis-driven reintervention (clinical restenosis) was 18.8% in subjects with low homocysteine concentrations and 19.0% in subjects with high homocysteine concentrations during the first year after the intervention ( P =0.93). Rates of clinical restenosis were 19.5%, 17.1%, and 23.3% in carriers of the 677CC, 677CT, and 677TT genotypes ( P =0.37), respectively, and 17.6%, 18.6%, and 24.7% in patients with the 1298AA, 1298AC, and 1298CC genotypes ( P =0.27), respectively.

Conclusions— Elevated levels of homocysteine and 2 polymorphisms of the MTHFR gene are not associated with restenosis after stenting in coronary arteries.

Depression and cardiovascular disease: mechanisms of interaction

This article explores the relationship between depression and cardiovascular disease from a mechanistic standpoint. Depression and cardiovascular disease are two of the most prevalent health problems in the United States and are the two leading causes of disability both in the United States and worldwide. Although depression is a known risk factor for the development of cardiovascular disease, as well as an independent predictor of poor prognosis following a cardiac event, the mechanistic relationship between the two remains unclear. Depression is associated with changes in an individual's health status that may influence the development and course of cardiovascular disease, including noncompliance with medical recommendations, as well as the presence of cardiovascular risk factors such as smoking and hypertension. In addition, depression is associated with physiologic changes, including nervous system activation, cardiac rhythm disturbances, systemic and localized inflammation, and hypercoagulability, that negatively influence the cardiovascular system. Further, stress may be an underlying trigger that leads to the development of both depression and cardiovascular disease. This article reviews seven potential mechanisms for the relationship between depression and cardiovascular disease and presents the available evidence surrounding each mechanism. Finally, future directions for research are discussed.

Homocysteine and atherothrombosis: diagnosis and treatment

Hyperhomocysteinemia has long been recognized as a risk factor for cardiovascular disease. Many cross-sectional and retrospective case-control studies have shown an association between elevated total homocysteine levels and coronary, peripheral, and cerebral vascular disease; prospective studies, however, have been inconsistent. Overall, there is evidence to suggest a modest association between elevated homocysteine levels and cardiovascular disease risk. Folate supplementation has been shown to reduce plasma homocysteine even when levels are in the normal range. Clinical studies suggest that lowering plasma homocysteine may improve endothelial dysfunction, a marker of atherothrombotic risk. The long-term effects of folate supplementation on homocysteine levels and cardiovascular disease risk await the results of ongoing clinical trials. However, several recent studies suggest a benefit for reduction of plasma homocysteine levels, as individuals with lower homocysteine have reduced cardiovascular event rates.

Secondary prevention with folic acid: effects on clinical outcomes

OBJECTIVES

We sought to conduct a randomized trial with folic acid 0.5 mg/day in a patient population with stable coronary artery disease (CAD).

BACKGROUND

Folic acid has favorable effects on vascular endothelium and lowers plasma homocysteine levels. In addition, homocysteine appears to be an independent risk factor for atherosclerotic disease. However, the value of folic acid in secondary prevention had seldom been tested.

METHODS

In this open-label study, 593 patients were included; 300 were randomized to folic acid and 293 served as controls. Mean follow-up time was 24 months. At baseline all patients had been on statin therapy for a mean of 3.2 years.

RESULTS

In patients treated with folic acid, plasma homocysteine levels decreased by 18%, from 12.0 +/- 4.8 to 9.4 +/- 3.5 micromol/l, whereas these levels remained unaffected in the control group (p < 0.001 between groups). The primary end point (all-cause mortality and a composite of vascular events) was encountered in 31 (10.3%) patients in the folic acid group and in 28 (9.6%) patients in the control group (relative risk 1.05; 95% confidence interval: 0.63 to 1.75). In a multifactorial survival model with adjustments for clinical factors, the most predictive laboratory parameters were, in order of significance, levels of creatinine clearance, plasma fibrinogen, and homocysteine.

CONCLUSIONS

Within two years, folic acid does not seem to reduce clinical end points in patients with stable coronary artery disease (CAD) while on statin treatment. Homocysteine might therefore merely be a modifiable marker of disease. Thus, low-dose folic acid supplementation should be treated with reservation, until more trial outcomes become available.

Total plasma homocysteine and restenosis after percutaneous coronary angioplasty: current evidence

BACKGROUND

Restenosis after percutaneous coronary angioplasty (PTCA) remains an important limitation of this procedure.

AIM

To assess the relationship between homocysteine levels and restenosis after PTCA, and discuss the potential benefit of homocysteine-lowering therapy.

METHOD

MEDLINE-based literature review.

RESULTS

The conflicting literature on the association between homocysteine levels and restenosis after PTCA can partially be explained by differences in methodology. Depending on the type of studies considered, a pooling of data resulted in a 22%-36% risk reduction of restenosis in lesions exposed to low homocysteine levels. The strongest reduction was found in balloon-only treated lesions (42%), while only a trend (14%) was seen in stented lesions. Based on the only available trial, homocysteine-lowering therapy yielded a 54% restenosis rate reduction, 76% in balloon-only treated lesions and 31% in stented lesions. Furthermore, homocysteine-lowering therapy provided a significant clinical benefit with a 40% relative reduction in major adverse events at 6 months' follow-up.

CONCLUSIONS

This review suggests that plasma homocysteine is a modifiable risk factor for restenosis, which when lowered improves outcome after PTCA. This inexpensive treatment with virtually no side-effects could therefore be considered as adjunctive therapy for patients undergoing PTCA, while awaiting results from further studies.