Validity of electron beam computed tomography for coronary artery disease: asystematic review and meta-analysis

Cardiovascular diagnosis in patients with rheumatoid arthritis, primary Sjögren's syndrome, systemic sclerosis and systemic lupus erhytematosus

Cardiovascular diseases (CVD) are the leading cause of death in the world and the most common type of comorbidity in patients with systemic lupus erythematosus (SLE), primary Sjögren's syndrome (SjS), systemic sclerosis (SSc), and rheumatoid arthritis (RA). Chronic inflammation in systemic rheumatic diseases can contribute to the development of CVD. Although risk factors for the CVD in the general population are well known, in patients with chronic rheumatic diseases risk factors for the CVD have not been specified as well as their connection with traditional risk factors, which would explain the increased incidence of CVD in these patients. Patients with chronic rheumatic diseases (RA, SLE, SjS and SSc) have an increased risk of developing both coronary and carotid atherosclerotic diseases. With the increase of the world's population suffering from rheumatoid autoimmune diseases, and thus increased morbidity and mortality, an adequate diagnostic strategy for the detection of coronary heart disease and risk stratification for their development is necessary. Functional techniques are readily available and can prove the presence of ischemia. In recent years, increasing attention has been paid to anatomical techniques that determine the degree of atherosclerosis. So far, a small number of studies are known that indicate the diagnostic accuracy and importance of functional and anatomical techniques in patients with autoimmune rheumatic diseases. The advantage of anatomical techniques is reflected in the direct visualization of either obstructive or non-obstructive (subclinical) coronary disease, allowing the detection of atherosclerosis in the early subclinical stage. However, information on the hemodynamic consequences of the detected changes remains unknown without functional testing. In asymptomatic patients with autoimmune rheumatic diseases, studies have shown an increased prevalence of silent ischemia and atherosclerosis and thus suggested early screening in the general population. Unfortunately, only a small number of prospective studies that have examined improved prognosis based on screening. Therefore, it is very important to conduct large prospective studies in terms of examining predictive markers of the occurrence and development of coronary heart disease in patients with autoimmune rheumatoid diseases.

Complement protein C3 and coronary artery calcium in middle-aged women with polycystic ovary syndrome and controls

Circulating complement protein C3 (C3) levels have been associated with coronary artery calcification (CAC) in women with systemic lupus erythematosus, but have yet to be evaluated in women with polycystic ovary syndrome (PCOS). We aimed to determine whether C3 levels were elevated in women with PCOS compared to controls and to quantify the association of C3 with cardiovascular disease (CVD) risk factors and CAC and if PCOS modified this association. This cross-sectional analysis included 132 women with PCOS and 155 controls, 35-62 years old, from the third visit of a case-control study. CAC was measured during the study visit, and circulating C3 was measured in stored sera. The presence of CAC and CAC categories (Agatston score 0, 1-9.9 and ≥ 10) were used for logistic and ordinal regression analysis, respectively. C3 levels were not significantly different between women with PCOS and controls. Among all women, C3 was associated with the presence of CAC and increasing CAC groups after adjusting for age, PCOS status and insulin or body mass index (BMI), all p<0.05. In addition, C3 was associated with the presence of CAC after adjusting for age, PCOS status, BMI, insulin and African American race, p=0.049. PCOS status did not modify these associations. In conclusion, circulating C3 levels may prove beneficial in identifying women at risk of CVD in women with PCOS and the general population.

Multicenter, Randomized Trial of Quantitative Pretest Probability to Reduce Unnecessary Medical Radiation Exposure in Emergency Department Patients With Chest Pain and Dyspnea

Background—

Use of pretest probability can reduce unnecessary testing. We hypothesize that quantitative pretest probability, linked to evidence-based management strategies, can reduce unnecessary radiation exposure and cost in low-risk patients with symptoms suggestive of acute coronary syndrome and pulmonary embolism.

Methods and Results—

This was a prospective, 4-center, randomized controlled trial of decision support effectiveness. Subjects were adults with chest pain and dyspnea, nondiagnostic ECGs, and no obvious diagnosis. The clinician provided data needed to compute pretest probabilities from a Web-based system. Clinicians randomized to the intervention group received the pretest probability estimates for both acute coronary syndrome and pulmonary embolism and suggested clinical actions designed to lower radiation exposure and cost. The control group received nothing. Patients were followed for 90 days. The primary outcome and sample size of 550 was predicated on a significant reduction in the proportion of healthy patients exposed to >5 mSv chest radiation. A total of 550 patients were randomized, and 541 had complete data. The proportion with >5 mSv to the chest and no significant cardiopulmonary diagnosis within 90 days was reduced from 33% to 25% ( P =0.038). The intervention group had significantly lower median chest radiation exposure (0.06 versus 0.34 mSv; P =0.037, Mann–Whitney U test) and lower median costs ($934 versus $1275; P =0.018) for medical care. Adverse events occurred in 16% of controls and 11% in the intervention group ( P =0.06).

Conclusions—

Provision of pretest probability and prescriptive advice reduced radiation exposure and cost of care in low-risk ambulatory patients with symptoms of acute coronary syndrome and pulmonary embolism.

Clinical Trial Registration—

URL: http://www.clinicaltrials.gov . Unique identifier: NCT01059500.

Plasma levels of advanced glycation endproducts are associated with type 1 diabetes and coronary artery calcification

Background

Advanced glycation endproducts (AGEs) may play a role in the development of coronary artery calcification (CAC) in type 1 diabetes (T1DM). We studied plasma AGEs in association with T1DM and CAC, and whether or not the latter association could be explained by low-grade inflammation (LGI) or endothelial dysfunction (ED).

Methods

We studied 165 individuals with and 169 without T1DM. CAC was quantified in a CAC score based on CT-scanning. Plasma levels of protein-bound pentosidine, N^ϵ-(carboxymethyl)lysine (CML) and N^ϵ-(carboxyethyl)lysine (CEL) were measured with HPLC/UPLC with fluorescence detection or tandem-mass spectrometry. Tetrahydropyrimidine (THP) was measured with ELISA, as were HsCRP, and sVCAM-1 and vWF, as markers for LGI and ED, respectively. Associations were analyzed with ANCOVA and adjusted for age, sex, BMI, waist-to-hip ratio, smoking, blood pressure, lipid profile, eGFR and T1DM.

Results

Individuals with T1DM had higher plasma levels of pentosidine, CML and THP compared with controls; means (95% CI) were 0.69 (0.65-0.73) vs. 0.51 (0.48-0.54) nmol/mmol LYS, p < 0.001; 105 (102–107) vs. 93 (90–95) nmol/mmol LYS, p < 0.001; and 126 (118–134) vs. 113 (106–120) U/mL, p = 0.03, respectively. Levels of pentosidine were higher in individuals with T1DM with a moderate to high compared with a low CAC score, means (95% CI) were 0.81 (0.70-0.93) vs. 0.67 (0.63-0.71) nmol/mmol LYS, p = 0.03, respectively. This difference was not attenuated by adjustment for LGI or ED.

Conclusions

We found a positive association between pentosidine and CAC in T1DM. These results may indicate that AGEs are possibly involved in the development of CAC in individuals with T1DM.

The impact of vitamin D deficiency on diabetes and cardiovascular risk

PURPOSE OF REVIEW

To review the association between vitamin D deficiency and diabetes and cardiovascular risk.

RECENT FINDINGS

Vitamin D deficiency is newly recognized as a common condition of increasing prevalence worldwide. Clinically, vitamin D has an established role in calcium and bone metabolism and has recently been shown to be associated with increased risk of developing type 1 and type 2 diabetes mellitus and cardiovascular disease (CVD), as well as with cardiovascular risk factors such as hypertension and obesity. The molecular mechanisms of these associations remain incompletely understood. The active metabolite of vitamin D regulates transcription of multiple gene products with antiproliferative, prodifferentiative, and immunomodulatory effects. Although vitamin D deficiency is frequently unrecognized clinically, laboratory measurement is easy to perform and treatment of vitamin D deficiency is relatively well tolerated and inexpensive. Limited, yet promising, results of proof-of-concept intervention studies of using vitamin D in diabetes will be presented.

SUMMARY

The high prevalence of vitamin D deficiency and plausible molecular mechanisms linking this to diabetes and cardiovascular risk suggest treatment of vitamin D deficiency to prevent and/or treat diabetes is a promising field to explore.

Nonacute coronary syndrome anginal chest pain

Anginal chest pain is one of the most common complaints in the outpatient setting. While much of the focus has been on identifying obstructive atherosclerotic coronary artery disease (CAD) as the cause of anginal chest pain, it is clear that microvascular coronary dysfunction (MCD) can also cause anginal chest pain as a manifestation of ischemic heart disease, and carries an increased cardiovascular risk. Epicardial coronary vasospasm, aortic stenosis, left ventricular hypertrophy, congenital coronary anomalies, mitral valve prolapse, and abnormal cardiac nociception can also present as angina of cardiac origin. For nonacute coronary syndrome (ACS) stable chest pain, exercise treadmill testing (ETT) remains the primary tool for diagnosis of ischemia and cardiac risk stratification; however, in certain subsets of patients, such as women, ETT has a lower sensitivity and specificity for identifying obstructive CAD. When combined with an imaging modality, such as nuclear perfusion or echocardiography testing, the sensitivity and specificity of stress testing for detection of obstructive CAD improves significantly. Advancements in stress cardiac magnetic resonance imaging enables detection of perfusion abnormalities in a specific coronary artery territory, as well as subendocardial ischemia associated with MCD. Coronary computed tomography angiography enables visual assessment of obstructive CAD, albeit with a higher radiation dose. Invasive coronary angiography remains the gold standard for diagnosis and treatment of obstructive lesions that cause medically refractory stable angina. Furthermore, in patients with normal coronary angiograms, the addition of coronary reactivity testing can help diagnose endothelial-dependent and -independent microvascular dysfunction. Lifestyle modification and pharmacologic intervention remains the cornerstone of therapy to reduce morbidity and mortality in patients with stable angina. This review focuses on the pathophysiology, diagnosis, and treatment of stable, non-ACS anginal chest pain.

Microvolt T-wave alternans as a predictor of mortality and severe arrhythmias in patients with left-ventricular dysfunction: a systematic review and meta-analysis

BACKGROUND

Studies have demonstrated that the use of implantable cardioverter defibrillators (ICDs) is effective for the primary prevention of arrhythmic events but due to imposing costs, there remains a need to identify which patients will derive the greatest benefit. Microvolt T-wave alternans (MTWA) has been proposed to assist in this stratification.

METHODS

We systematically searched the literature using MEDLINE, EMBASE, Current Contents, the Cochrane Library, INAHTA, and the Web of Science to identify all primary prevention randomized controlled trials and prospective cohort studies with at least 12 months of follow-up examining MTWA as a predictor of mortality and severe arrhythmic events in patients with severe left-ventricular dysfunction. The search was limited to full-text English publications between January 1990 and May 2007. The primary outcome was a composite of mortality and severe arrhythmias. Data were synthesized using Bayesian hierarchical models.

RESULTS

We identified no trials and 8 published cohort studies involving a total of 1,946 patients, including 332 positive, 656 negative, 84 indeterminate, and 874 non-negative (which includes both positive and indeterminate tests) MTWA test results. The risk of mortality or severe arrhythmic events was higher in patients with a positive MTWA compared to a negative test (RR = 2.7, 95% credible interval (CrI) = 1.4, 6.1). Similar results were obtained when comparing non-negative MTWA to a negative test.

CONCLUSION

A positive MTWA test predicts mortality or severe arrhythmic events in a population of individuals with severe left ventricular dysfunction. However, the wide credible interval suggests the clinical utility of this test remains incompletely defined, ranging from very modest to substantial. Additional high quality studies are required to better refine the role of MTWA in the decision making process for ICD implantation.