BMC Cardiovascular Disorders - Latest Articles

Increased Mortality among Survivors of Myocardial Infarction with Kidney Dysfunction: the Contribution of Gaps in the use of Guideline-Based Therapies

Pamela Peterson — 2009-07-08T00:00:00Z

Background: We assessed the degree to which differences in guideline-based medical therapy for acute myocardial infarction (AMI) contributes to the higher mortality associated with kidney disease. Methods: In the PREMIER registry, we evaluated patients from 19 US centers surviving AMI. Cox regression evaluated the association between estimated glomerular filtration rate (GFR) and time to death over two years, adjusting for demographic and clinical variables. The contribution of variation in guideline-based medical therapy to differences in mortality was then assessed by evaluating the incremental change in the hazard ratios after further adjustment for therapy. Results: Of 2426 patients, 26% had GFR>90, 44% had GFR=60-<90, 22% had GFR=30-<60, and 8% had GFR<30 ml/min/1.73m2. Greater degrees of renal dysfunction were associated with greater 2-year mortality and lower rates of guideline-based therapy among eligible patients. For patients with severely decreased GFR, adjustment for differences in guideline-based therapy did not significantly attenuate the relationship with mortality (HR 3.82, 95% CI 2.39-6.11 unadjusted; HR=3.90, 95% CI 2.42-6.28 after adjustment for treatment differences). Conclusions: Higher mortality associated with reduced GFR after AMI is not accounted for by differences in treatment factors, underscoring the need for novel therapies specifically targeting the pathophysiological abnormalities associated with kidney dysfunction to improve survival.

Younger age of escalation of cardiovascular risk factors in Asian Indian subjects

Rajeev Gupta — 2009-07-05T00:00:00Z

Background: Cardiovascular risk factors start early, track through the young age and manifest in middle age in most societies. We conducted epidemiological studies to determine prevalence and age-specific trends in cardiovascular risk factors among adolescent and young urban Asian Indians. Methods: Population based epidemiological studies to identify cardiovascular risk factors were performed in North India in 1999-2002. We evaluated major risk factors- smoking or tobacco use, obesity, truncal obesity, hypertension, dysglycemia and dyslipidemia using pre-specified definitions in 2051 subjects (male 1009, female 1042) aged 15-39 years of age. Age-stratified analyses were performed and significance of trends determined using regression analyses for numerical variables and Chi2 test for trend for categorical variables. Logistic regression was used to identify univariate and multivariate odds ratios (OR) for correlation of age and risk factors. Results: In males and females respectively, smoking or tobacco use was observed in 200 (11.8%) and 18 (1.4%), overweight or obesity (body mass index, BMI [greater than or equal to]25 kg/m2) in 12.4% and 14.3%, high waist-hip ratio, WHR (males >0.9, females >0.8) in 15% and 32.3%, hypertension in 5.6% and 3.1%, high LDL cholesterol (>130 mg/dl) in 9.4% and 8.9%, low HDL cholesterol (<40 mg/dl males, <50 mg/dl females) in 16.2% and 49.7%, hypertriglyceridemia (>150 mg/dl) in 9.7% and 6 %, diabetes in 1.0% and 0.4% and the metabolic syndrome in 3.4% and 3.6%. Significantly increasing trends with age for indices of obesity (BMI, waist, WHR), glycemia (fasting glucose, metabolic syndrome) and lipids (cholesterol, LDL cholesterol, HDL cholesterol) were observed (p for trend <0.01). At age 15-19 years the prevalence (%) of risk factors in males and females, respectively, was overweight/obesity in 7.6, 8.8; high WHR 4.9, 14.4; hypertension 2.3, 0.3; high LDL cholesterol 2.4, 3.2; high triglycerides 3.0, 3.2; low HDL cholesterol 8.0, 45.3; high total:HDL ratio 3.7, 4.7, diabetes 0.0 and metabolic syndrome in 0.0, 0.2 percent. At age groups 20-29 years in males and females, ORs were, for smoking 5.3, 1.0; obesity 1.6, 0.8; truncal obesity 4.5, 3.1; hypertension 2.6, 4.8; high LDL cholesterol 6.4, 1.8; high triglycerides 3.7, 0.9; low HDL cholesterol 2.4, 0.8; high total:HDL cholesterol 1.6, 1.0; diabetes 4.0, 1.0; and metabolic syndrome 37.7, 5.7 (p<0.05 for some). At age 30-39, ORs were- smoking 16.0, 6.3; overweight 7.1, 11.3; truncal obesity 21.1, 17.2; hypertension 13.0, 64.0; high LDL cholesterol 27.4, 19.5; high triglycerides 24.2, 10.0; low HDL cholesterol 15.8, 14.1; high total:HDL cholesterol 37.9, 6.10; diabetes 50.7, 17.4; and metabolic syndrome 168.5, 146.2 (p<0.01 for all parameters). Multivariate adjustment for BMI, waist size and WHR in men and women aged 30-39 years resulted in attenuation of ORs for hypertension and dyslipidemias. Conclusions: Low prevalence of multiple cardiovascular risk factors (smoking, hypertension, dyslipidemias, diabetes and metabolic syndrome) in adolescents and rapid escalation of these risk factors by age of 30-39 years is noted in urban Asian Indians. Interventions should focus on these individuals.

Monocytes and neutrophils expressing myeloperoxidase occur in fibrous caps and thrombi in unstable coronary plaques

Fabio Tavora — 2009-06-23T00:00:00Z

Background: Myeloperoxidase (MPO) -containing macrophages and neutrophils have been described at sites of plaque rupture. The presence of these cells in precursor lesions to acute rupture (thin cap atheroma, or vulnerable plaque) and within thrombi adjacent to ruptures has not been described, nor an association with iron-containing macrophages within unstable plaques. Methods: We studied 61 acute ruptures, 15 organizing ruptures, 31 thin cap fibroatheromas, and 28 fibroatheromas from 72 sudden coronary death victims by immunohistochemical and histochemical techniques. Inflammatory cells were typed with anti-CD68 (macrophages), anti-BP-30 (neutrophil bactericidal glycoprotein), and anti-MPO. Iron was localized by Mallory's Prussian blue stain. In selected plaques alpha smooth muscle actin (DAKO, Carpinteria, CA, clone M0851) was performed. Results: MPO positive cells were present in 79% of ruptured caps, 28% of thin cap fibroatheroma, and no fibroatheromas; neutrophils were present in 72% of ruptures, 8% of thin cap fibroatheromas, and no fibroatheromas. Iron containing foam cells were present in the caps of 93% of acute ruptures, of 85% of organizing ruptures, 20% of thin cap atheromas, and 10% of fibroatheromas. MPO positive cells were more frequent in occlusive than non-occlusive thrombi adjacent to ruptures (p = .006) and were more numerous in diabetics compared to non-diabetics (p = .002) Conclusion: Unstable fibrous caps are more likely to contain MPO-positive cells, neutrophils, and iron-containing macrophages than fibrous caps of stable fibroatheromas. MPO-positive cells in thrombi adjacent to disrupted plaques are associated with occlusive thrombi and are more numerous in diabetic patients.

Activation of calpain-1 in human carotid artery atherosclerotic lesions

Isabel Goncalves — 2009-06-18T00:00:00Z

Background: In a previous study, we observed that oxidized low-density lipoprotein-induced death of endothelial cells was calpain-1-dependent. The purpose of the present paper was to study the possible activation of calpain in human carotid plaques, and to compare calpain activity in the plaques from symptomatic patients with those obtained from patients without symptoms. Methods: Human atherosclerotic carotid plaques (n = 29, 12 associated with symptoms) were removed by endarterectomy. Calpain activity and apoptosis were detected by performing immunohistochemical analysis and TUNEL assay on human carotid plaque sections. An antibody specific for calpain-proteolyzed α-fodrin was used on western blots. Results: We found that calpain was activated in all the plaques and calpain activity colocalized with apoptotic cell death. Our observation of autoproteolytic cleavage of the 80 kDa subunit of calpain-1 provided further evidence for enzyme activity in the plaque samples. When calpain activity was quantified, we found that plaques from symptomatic patients displayed significantly lower calpain activity compared with asymptomatic plaques. Conclusion: These novel results suggest that calpain-1 is commonly active in carotid artery atherosclerotic plaques, and that calpain activity is colocalized with cell death and inversely associated with symptoms.

Profile and predictor of health-related quality of life among hypertensive patients in south western Nigeria

Michael Ogunlana — 2009-06-17T00:00:00Z

Background: The health-related quality of life (HRQOL) of hypertensives may be influenced by blood pressure, adverse effects of drugs used to treat hypertension, or other factors, such as the labelling effect, or beliefs and attitudes about illness and treatment. There is paucity of information on the determinants of HRQOL among black hypertensives especially in the developing countries such as Nigeria. This study describes the HRQOL and its determinants among black patients diagnosed and treated for Hypertension in Nigeria. Methods: The study was a cross sectional in design that involved 265 hypertensive patients receiving treatment at the medical outpatient unit of the Federal Medical Centre Abeokuta, Nigeria. They were all consecutive patients that presented at the hospital during the period of the study who meet the inclusion criteria and consented to participate in the study. Demographic data, disease characteristics such as symptoms and signs and recent drug history were obtained from the patients and their hospital records as documented by the physician. The SF-36 questionnaire was administered once by interview to the participants to measure their HRQOL. Descriptive statistics was used in summarizing the demographic data and hypertension related histories of the participants. Multiple linear regression was used to model for the influence of socio demographic and clinical variables of the hypertensives on their HRQOL. Results: Physical functioning domain mean score was far below average (33.53 ± 29.65). Role physical and role emotional domains were a little above average (54.7 ± 40.4, 51.1 ± 40.6 respectively). Role Physical (p = 0.043), Role Emotional (p = 0.003), Vitality (p = 0.014) and Mental Health (p = 0.034) domain mean scores for patients with controlled BP were significantly higher than patients with uncontrolled BP. The overall HRQOL was significantly better in the group of hypertensives with controlled blood pressure (p = 0.014). Increasing blood pressure (p = 0.005) and symptom count (p < 0.001), the presence of stroke (p = 0.008) and visual impairment (p = 0.015) were significant negative predictors of the overall HRQOL. Conclusion: This study provides evidence for a model that links patients' status with regard to biology (blood pressure), symptoms, and functionality (HRQOL) and may prove useful in guiding follow-up of patients who receive treatment for hypertension. Identification of patient's symptoms, blood pressure, complication/comorbidity and changes in functioning may help clinicians increase their effectiveness in helping patients maintain adherent behaviour with drug and non drug interventions in chronic diseases such as hypertension.

Quick Identification of acute Chest pain patients - Study (QICS)

Hendrik Willemsen — 2009-06-15T00:00:00Z

Background: Patients with acute chest pain are often referred to the emergency ward and extensively investigated. Investigations are costly and could induce unnecessary complications, especially with invasive diagnostics. Nevertheless, chest pain patients have high mortalities. Fast identification of high-risk patients is crucial. Therefore several strategies have been developed including specific symptoms, signs, laboratory measurements, and imaging.Methods/DesignThe Quick Identification of acute Chest pain Study (QICS) will investigate whether a combined use of specific symptoms and signs, electrocardiography, routine and new laboratory measures, adjunctive imaging including electron beam (EBT) computed tomography (CT) and contrast multislice CT (MSCT) will have a high diagnostic yield for patients with acute chest pain. All patients will be investigated according a standardized protocol in the Emergency Department. Serum and plasma will be frozen for future analysis for a wide range of biomarkers at a later time point. The primary endpoint is the safe recognition of low-risk chest pain patients directly at presentation. Secondary endpoint is the identification of a wide range of sensitive predictive clinical markers, chemical biomarkers and radiological markers in acute chest pain patients. Chemical biomarkers will be compared to quantitative CT measurements of coronary atherosclerosis as a surrogate endpoint. Chemical biomarkers will also be compared in head to head comparison and for their additional value.DiscussionThis will be a very extensive investigation of a wide range of risk predictors in acute chest pain patients. New reliable fast and cheap diagnostic algorithm resulting from the test results might improve chest pain patients' prognosis, and reduce unnecessary costs and diagnostic complications.

The effect on cardiovascular risk factors of migration from rural to urban areas in Peru: PERU MIGRANT Study

J. Jaime Miranda — 2009-06-08T00:00:00Z

Background: Mass-migration observed in Peru from the 1970s occurred because of the need to escape from politically motivated violence and work related reasons. The majority of the migrant population, mostly Andean peasants from the mountainous areas, tends to settle in clusters in certain parts of the capital and their rural environment could not be more different than the urban one. Because the key driver for migration was not the usual economic and work-related reasons, the selection effects whereby migrants differ from non-migrants are likely to be less prominent in Peru. Thus the Peruvian context offers a unique opportunity to test the effects of migration.Methods/DesignThe PERU MIGRANT (PEru's Rural to Urban MIGRANTs) study was designed to investigate the magnitude of differences between rural-to-urban migrant and non-migrant groups in specific CVD risk factors. For this, three groups were selected: Rural, people who have always have lived in a rural environment; Rural-urban, people who migrated from rural to urban areas; and, Urban, people who have always lived in a urban environment.DiscussionOverall response rate at enrolment was 73.2% and overall response rate at completion of the study was 61.6%. A rejection form was obtained in 282/323 people who refused to take part in the study (87.3%). Refusals did not differ by sex in rural and migrant groups, but 70% of refusals in the urban group were males. In terms of age, most refusals were observed in the oldest age-group (>60 years old) in all study groups. The final total sample size achieved was 98.9% of the target sample size (989/1000). Of these, 52.8% (522/989) were females. Final size of the rural, migrant and urban study groups were 201, 589 and 199 urban people, respectively. Migrant's average age at first migration and years lived in an urban environment were 14.4 years (IQR 10–17) and 32 years (IQR 25–39), respectively.This paper describes the PERU MIGRANT study design together with a critical analysis of the potential for bias and confounding in migrant studies, and strategies for reducing these problems. A discussion of the potential advantages provided by the case of migration in Peru to the field of migration and health is also presented.

The Stroke Outcomes Study 2 (SOS2): a prospective, analytic cohort study of depressive symptoms after stroke.

Kate Hill — 2009-06-01T00:00:00Z

Background: Mood disorder is recognised as an important and common problem after stroke but little is known about the longer term effects of mood on functional outcomes. This protocol paper describes the Stroke Outcomes Study 2 (SOS2), a research study conducted in two large acute NHS Trusts in the North of England, which was designed to investigate the impact of early depressive symptoms on outcomes after an acute stroke.Methods and designSOS2 was a prospective cohort study that aimed to recruit patients in the first few weeks after a stroke, and to follow them up at regular intervals for one year thereafter in order to describe the trajectory of psychological symptoms and study their impact on physical functional recovery. Measures of mood and function were completed at baseline (approximately 3 weeks) and at four follow-up time-points: approximately 9, 13, 26 and 52 weeks after the index stroke.DiscussionRecruiting patients to research studies soon after an acute stroke is difficult. Mortality following stroke is approximately 30% and in the region of half the patients that survive the initial event are significantly disabled. Together these factors reduced the number of patients available to participate in SOS2 but once recruited to the study the drop-out rate was relatively low. During the recruitment period over 6000 admissions for stroke or query stroke were screened for eligibility. A cohort of 592 study participants was finally achieved.

Swedish snuff and incidence of cardiovascular disease.A population-based cohort study

Ellis Janzon — 2009-05-27T00:00:00Z

Background: The relationship between smoking and an increased incidence of cardiovascular diseases is well known. Whether smokeless tobacco (snuff) is related to myocardial infarction (MI) or stroke is still controversial. Aim of this study was to explore whether snuff users have an increased incidence of MI or stroke. Methods: A total of 16 754 women and 10 473 men (aged 45–73 years), without history of cardiovascular disease (CVD), belonging to the population-based "Malmö Diet and Cancer" study were examined. Incidence of MI and stroke were monitored over 10.3 years. Results: Snuff was used by 737 (7.0%) men and 75 (0.4%) women, respectively. Among men, snuff was significantly associated with low occupation level, single civil status, high BMI and with current and former smoking. In women, snuff was associated with lower systolic blood pressure. A total of 964 individuals (3.5%), i.e.544 men (5.3%) and 420 (2.5%) women suffered a MI during the follow-up period. The corresponding numbers of incident stroke cases were 1048, i.e. 553 men (5.3%) and 495 (3.0%) women, respectively. Snuff was not associated with any statistically significant increased risk of MI or stroke in men or women. The relative risks (RR) in male snuff users compared to non-users were 1.05 (95% confidence interval (CI): 0.8–1.4, p = 0.740) for incident MI and 0.97 (0.7–1.4, p = 0.878) for stroke, after taking age and potential confounders into account. In women none of the 420 (2.5%) women who were snuff users had a MI and only one suffered a stroke during the follow-up. Conclusion: Several life-style risk factors were more prevalent in snuff-users than in non-users. However, the present study does not support any relationship between snuff and incidence of cardiovascular disease in men.

Reproducibility of wrist home blood pressure measurement with position sensor and automatic data storage

Sakir Uen — 2009-05-27T00:00:00Z

Background: Wrist blood pressure (BP) devices have physiological limits with regards to accuracy, therefore they were not preferred for home BP monitoring. However some wrist devices have been successfully validated using etablished validation protocols. Therefore this study assessed the reproducibility of wrist home BP measurement with position sensor and automatic data storage. Methods: To compare the reproducibility of three different(BP) measurement methods: 1) office BP, 2) home BP (Omron wrist device HEM- 637 IT with position sensor), 3) 24-hour ambulatory BP(24-h ABPM) (ABPM-04, Meditech, Hun)conventional sphygmomanometric office BP was measured on study days 1 and 7, 24-h ABPM on study days 7 and 14 and home BP between study days 1 and 7 and between study days 8 and 14 in 69 hypertensive and 28 normotensive subjects. The correlation coeffcient of each BP measurement method with echocardiographic left ventricular mass index was analyzed. The schedule of home readings was performed according to recently published European Society of Hypertension (ESH)- guidelines. Results: The reproducibility of home BP measurement analyzed by the standard deviation as well as the squared differeces of mean individual differences between the respective BP measurements was significantly higher than the reproducibility of office BP (p < 0.001 for systolic and diastolic BP) and the reproducibility of 24-h ABPM (p < 0.001 systolic BP, p = 0.127 diastolic BP). The reproducibility of systolic and diastolic office versus 24-h ABPM was not significantly different (p = 0.80 systolic BP, p = 0.1 diastolic BP). The correlation coefficient of 24-h ABMP (r = 0.52) with left ventricular mass index was significantly higher than with office BP (r = 0.31). The difference between 24-h ABPM and home BP (r = 0.46) was not significant. Conclusion: The short-term reproducibility of home BP measurement with the Omron HEM-637 IT wrist device was superior to the reproducibility of office BP and 24- h ABPM measurement. Furthermore, home BP with the wrist device showed similar correlations to targed organ damage as recently reported for upper arm devices. Although wrist devices have to be used cautious and with defined limitations, the use of validated devices with position sensor according to recently recommended measurement schedules might have the potential to be used for therapy monitoring.