Measurements of wall shear stress and aortic pulse wave velocity in swine with familial hypercholesterolemia.

PURPOSE: To assess measurements of pulse wave velocity (PWV) and wall shear stress (WSS) in a swine model of atherosclerosis. MATERIALS AND METHODS: Nine familial hypercholesterolemic (FH) swine with angioplasty balloon catheter-induced atherosclerotic lesions to the abdominal aorta (injured group) and 10 uninjured FH swine were evaluated with a 4D phase contrast (PC) magnetic resonance imaging (MRI) acquisition, as well as with radial and Cartesian 2D PC acquisitions, on a 3T MR scanner. PWV values were computed from the 2D and 4D PC techniques, compared between the injured and uninjured swine, and validated against reference standard pressure probe-based PWV measurements. WSS values were also computed from the 4D PC MRI technique and compared between injured and uninjured groups. RESULTS: PWV values were significantly greater in the injured than in the uninjured groups with the 4D PC MRI technique (P = 0.03) and pressure probes (P = 0.02). No significant differences were found in PWV between groups using the 2D PC techniques (P = 0.75-0.83). No significant differences were found for WSS values between the injured and uninjured groups. CONCLUSION: The 4D PC MRI technique provides a promising means of evaluating PWV and WSS in a swine model of atherosclerosis, providing a potential platform for developing the technique for the early detection of atherosclerosis.

Current status of preventive cardiology training among United States cardiology fellowships and comparison to training guidelines.

We evaluated preventive cardiology education in United States cardiology fellowship programs and their adherence to Core Cardiovascular Training Symposium training guidelines, which recommend 1 month of training, faculty with expertise, and clinical experience in cardiac rehabilitation, lipid disorder management, and diabetes management as a part of the prevention curricula. We sent an anonymous survey to United States cardiology program directors and their chief fellow. The survey assessed the program curricula, rotation structure, faculty expertise, obstacles, and recommended improvements. The results revealed that 24% of surveyed programs met the Core Cardiovascular Training Symposium guidelines with a dedicated 1-month rotation in preventive cardiology, 24% had no formalized training in preventive cardiology, and 30% had no faculty with expertise in preventive cardiology, which correlated with fewer rotations in prevention than those with specialized faculty (p = 0.009). Fellows rotated though the following experiences (% of programs): cardiac rehabilitation, 71%; lipid management, 37%; hypertension, 15%; diabetes, 7%; weight management/obesity, 6%; cardiac nutrition, 6%; and smoking cessation, 5%. The program directors cited "lack of time" as the greatest obstacle to providing preventive cardiology training and the chief fellows reported "lack of a developed curriculum" (p = 0.01). The most recommended improvement was for the American College of Cardiology to develop a web-based curriculum/module. In conclusion, most surveyed United States cardiology training programs currently do not adhere to basic preventive cardiovascular medicine Core Cardiovascular Training Symposium recommendations. Additional attention to developing curricular content and structure, including the creation of an American College of Cardiology on-line knowledge module might improve fellowship training in preventive cardiology.

Lipid testing in patients with rheumatoid arthritis and key cardiovascular-related comorbidities: a medicare analysis.

OBJECTIVE: For patients with rheumatoid arthritis (RA) and comorbid cardiovascular disease (CVD), diabetes, or hyperlipidemia, annual lipid testing is recommended to reduce morbidity and mortality from comorbidities. Given trends encouraging complex patients to receive care in "medical homes," we examined associations between regularly seeing a primary care provider (PCP) and lipid testing in RA patients with cardiovascular-related comorbidities. METHODS: We performed a retrospective cohort study examining a 5% random USA Medicare sample (2004-06) of beneficiaries over 65 years old with RA and concomitant CVD, diabetes, or hyperlipidemia (n = 16,893). We examined the relationship between receiving lipid testing in 2006 and having at least 1 PCP visit per year in 2004, 2005, and 2006 using multivariate regression. RESULTS: Ninety percent of patients had prevalent CVD; 46% had diabetes, and 64% had hyperlipidemia. However, annual lipid testing was only performed in 63% of these RA patients. Thirty percent of patients saw a PCP less than once per year, despite frequent visits (mean >9) with other providers. Patients without at least 1 annual PCP visit were 16% less likely to have lipid testing. Increased age, complexity scores, hospitalization, and large town residence predicted decreased lipid testing. CONCLUSIONS: Despite comorbid CVD, diabetes, or hyperlipidemia, 30% of Medicare RA patients saw a PCP less than once per year, and 1 in 3 lacked annual lipid testing. Findings support advocating primary care visits at least once per year. Remaining gaps in lipid testing suggest the need for additional strategies to improve lipid testing in at-risk RA patients.

Long-term effects of smoking and smoking cessation on exercise stress testing: three-year outcomes from a randomized clinical trial.

BACKGROUND: The long-term effects of smoking and smoking cessation on markers of cardiovascular disease (CVD) prognosis obtained during treadmill stress testing (TST) are unknown. The purpose of this study was to evaluate the long-term effects of smoking cessation and continued smoking on TST parameters that predict CVD risk. METHODS: In a prospective, double-blind, randomized, placebo-controlled trial of 5 smoking cessation pharmacotherapies, symptom-limited TST was performed to determine peak METs, rate-pressure product (RPP), heart rate (HR) increase, HR reserve, and 60-second HR recovery, before and 3 years after the target smoking cessation date. Relationships between TST parameters and treatments among successful abstainers and continuing smokers were evaluated using multivariable analyses. RESULTS: At baseline, the 600 current smokers (61% women) had a mean age of 43.4 (SD 11.5) years and smoked 20.7 (8.4) cigarettes per day. Their exercise capacity was 8.7 (2.3) METs, HR reserve was 86.6 (9.6)%, HR increase was 81.1 (20.9) beats/min, and HR recovery was 22.3 (11.3) beats. Cigarettes per day and pack-years were independently and inversely associated with baseline peak METs (P < .001), RPP (P < .01, pack-years only), HR increase (P < .05), and HR reserve (P < .01). After 3 years, 168 (28%) had quit smoking. Abstainers had greater improvements than continuing smokers (all P < .001) in RPP (2,055 mm Hg beats/min), HR increase (5.9 beats/min), and HR reserve (3.7%), even after statistical adjustment (all P < .001). CONCLUSIONS: Smokers with a higher smoking burden have lower exercise capacity, lower HR reserve, and a blunted exercise HR response. After 3 years, TST improvements suggestive of improved CVD prognosis were observed among successful abstainers.

Ambulatory activity associations with cardiovascular and metabolic risk factors in smokers.

BACKGROUND: We examined the association between ambulatory activity and biological markers of health in smokers. METHODS: Baseline data from 985 subjects enrolled in a pharmacologic smoking cessation trial were examined. Body size, blood pressure, total cholesterol (TC), low density lipoprotein cholesterol (LDL-C), total and small LDL particles, LDL size, high density lipoprotein cholesterol, triglycerides (TG), C-reactive protein (CRP), creatinine, fasting glucose, and hemoglobin A1c were assessed in relation to pedometer-assessed ambulatory activity, as was the odds of metabolic syndrome and CRP > 3 mg/L. Effect modification by gender was examined. RESULTS: Only waist circumference was lower with greater steps/day in the men and women combined (P(trend) < 0.001). No other significant relationships were noted in men, while women with ≥ 7500 steps/day had lower weight, BMI, CRP, TG, total, and small LDL particles compared with those with < 7500 steps/day. These women also had 62% and 43% lower odds of metabolic syndrome and elevated CRP, respectively, compared with the less active women. Adjustment for BMI attenuated all the associations seen in women. CONCLUSIONS: Greater ambulatory activity is associated with lower levels of metabolic and cardiovascular risk factors in female smokers which may, in part, be mediated by a reduction in BMI.

Rationale for targeted rather than population based screening with C-reactive protein using the National Health and Nutrition Examination Survey (1999 to 2002).

C-reactive protein (CRP) is the most well-studied inflammatory marker for the prediction of coronary artery disease. It was hypothesized that population-wide screening would have minimal impact but that a target population might be identified for whom CRP testing could be appropriate. The National Health and Nutrition Examination Survey (NHANES; 1999 to 2002) included 7,399 subjects who represented 171 million United States residents aged 20 to 79 years. Subjects were risk stratified according to National Cholesterol Education Program Adult Treatment Panel III guidelines. Subjects with CRP levels >3 mg/L then had their risk profiles adjusted by adding 1 risk factor and multiplying their Framingham risk scores by 1.5. Subjects had their low-density lipoprotein (LDL) cholesterol goals adjusted as necessary and were then recategorized as above or below their CRP-adjusted LDL cholesterol goal. LDL cholesterol goals were met initially by 67.8% (116 +/- 8 million) of United States residents, and 64.8% (111 +/- 8 million) achieved their LDL cholesterol goals after CRP adjustment. Thus, 5.3 +/- 1.1 million of the population (3.1 +/- 0.1%) had their risk modified in a clinically meaningful way by CRP adjustment. Targeting the screening to 2 groups, those with 1 risk factor and LDL cholesterol levels 130 to 159 mg/dl and those with moderately high risk and LDL cholesterol levels 100 to 129 mg/dl, we were able to identify all 5.3 million by screening only 14.8 million, achieving a screening yield of 35%. In conclusion, population-based screening with CRP provided a clinical impact for only 3.1% of United States residents. Patients with 1 risk factor and LDL cholesterol levels of 130 to 159 mg/dl and those with moderately high risk and LDL cholesterol levels of 100 to 129 mg/dl represent high-yield subgroups for routine CRP screening.

Medical records as sources of data on cardiovascular disease events in persons with diabetes.

PURPOSE: The aim of this study is to evaluate medical records as a source of data on cardiovascular disease over a 20-year interval. METHODS: Participants in a population-based cohort of persons with Type 1 diabetes were asked whether they had been told by a doctor that they had several specific cardiovascular events. In addition, they were asked when and where they were hospitalized for myocardial infarction, stroke, surgical procedures, and for other conditions and procedures. The medical care institution was contacted to obtain copies of the relevant hospitalization. RESULTS: Overall, the confirmation of the self-reported events was 86.0% when medical records were obtained. Percent confirmed varied with the diagnosis. Reports of poor circulation in the lower extremities were confirmed in 42.6%, stroke was confirmed in 70%, and coronary bypass surgery was confirmed in 100% of cases. The success of obtaining medical records was greater for those events that were reported to have occurred more recently than those reported further in the past, especially when 10 or more years had elapsed. CONCLUSION: Medical record confirmation of reported cardiovascular events in persons with Type 1 diabetes was high for some events when medical records could be obtained but was lower for "poor circulation" to the legs and stroke possibly related to the lack of specificity of our questions, to incorrect attribution of symptoms by the respondent, or to inaccurate recall of a physician's examination. Medical record confirmation was better for more recent than past events. Therefore, when hard copy documentation is needed, it should be sought within 10 years of the event.

Web-based resources for medical nutrition education.

The World Wide Web is a valuable source of nutrition and health information, but the time and effort required to take advantage of this resource may stand in the way of routine use in medical education and practice. The Nutrition Academic Award (NAA) has produced numerous examples of Web-based nutrition resources, including nutrition assessment tools, patient education materials, and presentations and curricula for professional education. The University of Wisconsin Medical Nutrition Handbook provides evidence-based nutrition care guides for common clinical problems, including obesity, diabetes, hypertension, lipid disorders, and the metabolic syndrome. Incorporation of these resources into medical practice may increase the provision of effective nutrition care.

Office systems for heart disease prevention.

The provision of heart disease prevention services in primary care is currently inadequate, but can be improved with the establishment of a practice system. The system process involves all members of the practice in a clearly defined, well-organized approach to patient care. An initial review of patient care services will help practices identify prevention areas that they would like to improve by defining protocols, roles, and routines within the practice. Once established, the prevention system can improve patient care and satisfaction of practice staff and physicians, but requires on-going assessment, modification, and commitment.

Postprandial lipoprotein changes in patients taking antiretroviral therapy for HIV infection.

OBJECTIVE: Dyslipidemia is common among patients receiving antiretroviral therapy for HIV infection. The purpose of this study was to determine whether postprandial lipemia contributes to the dyslipidemia observed in HIV-positive patients taking antiretroviral therapy. METHODS AND RESULTS: A standardized fat load was administered to 65 subjects (group 1 35 HIV-positive subjects receiving protease inhibitors [PIs]; group 2 20 HIV-positive subjects not receiving PIs; group 3 10 HIV-negative controls). Serum triglycerides, retinyl palmitate, and lipoproteins were measured using enzymatic and nuclear magnetic resonance spectroscopic techniques. Compared with HIV-negative controls, peak postprandial retinyl palmitate and large very low-density lipoprotein (VLDL) levels occurred later in both HIV-positive groups, and a delayed decrease in serum triglycerides was observed. However, postprandial areas under the curve (AUCs) for triglycerides, retinyl palmitate, chylomicrons, and large VLDL were similar. Postprandial AUCs for intermediate-density lipoproteins (IDLs) and low-density lipoproteins (LDLs) were higher in group 1 than groups 2 and 3 (all P<0.035). CONCLUSIONS: Postprandial clearance of triglyceride-rich lipoproteins is delayed in HIV-positive individuals receiving antiretroviral therapy. Compared with HIV-positive individuals not on PIs, those taking PIs do not have increased postprandial triglyceride-rich lipoproteins but do have increased postprandial IDLs and LDLs. An oral fat load was administered to 55 HIV-positive and 10 HIV-negative individuals. Postprandial clearance of triglyceride-rich lipoproteins was delayed in HIV-positive individuals. Compared with HIV-positive subjects not on PIs, those taking PIs do not have increased postprandial triglyceride-rich lipoproteins but do have increased postprandial intermediate-density and low-density lipoproteins.

Vascular age: integrating carotid intima-media thickness measurements with global coronary risk assessment.

BACKGROUND: An imaging test that quantifies atherosclerotic burden and that can be integrated with existing risk stratification paradigms would be a very useful clinical tool. HYPOTHESIS: Measurement of carotid intima-media thickness (CIMT) is feasible in a clinical setting. Such measurements can be integrated into coronary risk assessment models. METHODS: Carotid intima-media thickness was measured by B-mode ultrasound in 82 consecutive patients without manifest atherosclerotic vascular disease. The values were used to determine "vascular age" (VA) based on nomograms from the Atherosclerosis Risk in Communities study. Vascular age was substituted for chronological age and standard and vascular age-adjusted 10-year coronary heart disease (CHD) risk estimates were compared. RESULTS: The mean chronological age was 55.8 +/- 9.0 years. The mean VA using CIMT was 65.5 +/- 18.9 years (p < 0.001). The Framingham 10-year hard CHD risk estimate was 6.5 +/- 4.9%. Substituting CIMT-derived VA for chronological age increased the 10-year CHD risk estimate to 8.0 +/- 6.8% (p < 0.001). Of 14 subjects initially at intermediate risk, 5 (35.7%) were reclassified as higher risk and 2 (14.3%) were reclassified as lower risk. Significant predictors of reclassification were tobacco use, high-density lipoprotein cholesterol, systolic blood pressure, and low-density lipoprotein cholesterol. CONCLUSIONS: Measurement of CIMT, a noninvasive estimate of current atherosclerotic burden, is feasible in a clinical setting and can be integrated into CHD risk assessment models. Determining VA using CIMT values may help individualize the age component of population-based CHD risk estimates. This strategy should be tested in a large trial with hard clinical endpoints.