Novedades en imagen cardiaca 2013

Cardiac imaging is a cornerstone of diagnosis in heart conditions, and an essential tool for assessing prognosis and establishing treatment decisions. This year, echocardiography stands out as a guide in interventional procedures and in choosing the size of the prosthesis. It is also proving to be a valuable technique in low-flow, low-gradient aortic stenosis. Three-dimensional echocardiography is advancing our knowledge of cardiac anatomy and valvular measurements. The parameters indicating tissue deformation have predictive power in valve disease and in the follow-up of drug-induced cardiotoxicity. Single-photon emission computed tomography and positron emission tomography are proving useful in ischemic heart disease and in the diagnosis of cardiac inflammation and infections. The role of computed tomography has been strengthened in noninvasive coronary angiography, the emergency room management of chest pain, assessment of chronic occlusions, and morphologic study of coronary plaque. Cardiac magnetic resonance imaging remains the gold standard for tissue characterization in ischemic heart disease and cardiomyopathies, and is assuming a greater role in stress studies and in the assessment of myocardial viability.     

Relationship of lipid oxidation with subclinical atherosclerosis and 10-year coronary events in general population

Objectives

To assess 1) the association of lipid oxidation biomarkers with 10-year coronary artery disease (CAD) events and subclinical atherosclerosis, and 2) the reclassification capacity of these biomarkers over Framingham-derived CAD risk functions, in a general population.

Methods

Within the framework of the REGICOR study, 4782 individuals aged between 25 and 74 years were recruited in a population-based cohort study. Follow-up of the 4042 who met the eligibility criteria was carried out. Plasma, circulating oxidized low-density lipoprotein (oxLDL) and oxLDL antibodies (OLAB) were measured in a random sample of 2793 participants.End-points included fatal and non-fatal acute myocardial infarction (AMI) and angina. Carotid intima-media thickness (IMT) in the highest quintile and ankle-brachial index <0.9 were considered indicators of subclinical atherosclerosis.

Results

Mean age was 50.0 (13.4) years, and 52.4% were women. There were 103 CAD events (34 myocardial infarction, 43 angina, 26 coronary deaths), and 306 subclinical atherosclerosis cases. Oxidized LDL was independently associated with higher incidence of CAD events (HR = 1.70; 95% Confidence Interval: 1.02–2.84), but not with subclinical atherosclerosis. The net classification index of the Framingham-derived CAD risk function was significantly improved when ox-LDL was included (NRI = 14.67% [4.90; 24.45], P = 0.003). No associations were found between OLAB and clinical or subclinical events. The reference values for oxLDL and OLAB are also provided (percentiles).

Conclusions

OxLDL was independently associated with 10-year CAD events but not subclinical atherosclerosis in a general population, and improved the reclassification capacity of Framingham-derived CAD risk functions.     

Association of Long-Term Exposure to Traffic-Related Air Pollution with Blood Pressure and Hypertension in an Adult Population–Based Cohort in Spain (the REGICOR Study)

Background: Long-term exposure to traffic-related air pollution may increase blood pressure (BP) and induce hypertension. However, evidence supporting these associations is limited, and they may be confounded by exposure to traffic noise and biased due to inappropriate control for use of BP-lowering medications.Objectives: We evaluated the associations of long-term traffic-related air pollution with BP and prevalent hypertension, adjusting for transportation noise and assessing different methodologies to control for BP-lowering medications.Methods: We measured systolic (SBP) and diastolic BP (DBP) at baseline (years 2003–2005) in 3,700 participants, 35–83 years of age, from a population-based cohort in Spain. We estimated home outdoor annual average concentrations of nitrogen dioxide (NO₂) with a land-use regression model. We used multivariate linear and logistic regression.Results: A 10-μg/m³ increase in NO₂ levels was associated with 1.34 mmHg (95% CI: 0.14, 2.55) higher SBP in nonmedicated individuals, after adjusting for transportation noise. Results were similar in the entire population after adjusting for medication, as commonly done, but weaker when other methods were used to account for medication use. For example, when 10 mmHg were added to the measured SBP levels of medicated participants, the association was β = 0.78 (95% CI: –0.43, 2.00). NO₂ was not associated with hypertension. Associations of NO₂ with SBP and DBP were stronger in participants with cardiovascular disease, and the association with SBP was stronger in those exposed to high traffic density and traffic noise levels ≥ 55 dB(A).Conclusions: We observed a positive association between long-term exposure to NO₂ and SBP, after adjustment for transportation noise, which was sensitive to the methodology used to account for medication.Citation: Foraster M, Basagaña X, Aguilera I, Rivera M, Agis D, Bouso L, Deltell A, Marrugat J, Ramos R, Sunyer J, Vila J, Elosua R, Künzli N. 2014. Association of long-term exposure to traffic-related air pollution with blood pressure and hypertension in an adult population–based cohort in Spain (the REGICOR study). Environ Health Perspect 122:404–411; http://dx.doi.org/10.1289/ehp.1306497     

Ischemic stroke in prediabetic patients

To describe the clinical characteristics of first-ever ischemic stroke (IS) patients with prediabetes, and to compare them with diabetes mellitus (DM) and non-DM patient characteristics. Retrospective analysis of a prospective series of first-ever acute IS patients. Patients were classified as non-DM (HbA1c during admission <5.7 % and no previous evidence of 2 or more fasting glucose >126 mg/dL), prediabetes (HbA1c from 5.7 to 6.4 %), and DM (previous DM diagnosis or HbA1c ≥6.5 % independently of current blood glucose). Demographic and clinical characteristics were compared between the three groups, along with outcome data [early neurological deterioration (END), 3-month poor outcome, 3-month mortality, outcome after rtPA treatment]. No demographic differences were observed. Prediabetic patients had more arterial hypertension (p = 0.006) and higher waist circumference (p < 0.0001) than non-DM patients, and DM patients had more hypercholesterolemia (p < 0.0001), body mass index (p = 0.017), and coronary artery disease (p = 0.005) than prediabetics. There were differences in TOAST subtype distribution (p < 0.0001). There were no differences in rtPA treatment success rate between groups. Multivariate analysis adjusted by age and stroke severity showed that DM but not prediabetes is an independent factor associated with END and 3-month poor outcome. Prediabetic patients with IS exhibit an “intermediate” vascular risk factor profile between that of non-DM and DM patients. In contrast to DM patients, IS prognosis in patients with prediabetes is similar to non-DM patients.     

Long-Term Follow-up Assessment After the Arterial Switch Operation for Correction of Dextro-Transposition of the Great Arteries by Means of Exercise Myocardial Perfusion-Gated SPECT

The arterial switch operation (ASO) is the preferred technique for correcting transposition of the great arteries, but translocation and reimplantation of the coronary arteries can produce myocardial ischemia. This report aims to describe the authors’ experience with exercise single-photon emission computed tomography (SPECT) used to evaluate myocardial perfusion. Exercise-rest gated-myocardial perfusion SPECT was performed for 69 patients (49 boys; median age, 9 years; 5th percentile [6.4 years] to 95th percentile [15.6 years]), 64 of whom were asymptomatic 9.98 ± 3.20 years after ASO. During exercise testing, the patients reached 9.85 ± 3.05 metabolic equivalents (METs) and a median heart rate of 160 beats per minute (bpm), 5th percentile (106 bpm) to 95th percentile (196 bpm). Whereas 61 patients (88.41 %) had normal myocardial perfusion, 2 patients (2.9 %) had reversible defects, and 6 patients (8.7 %) had fixed defects. All the patients with perioperative ischemic complications (4/4, 100 %) had myocardial perfusion defects, whereas four patients (4/65, 6.15 %) without ischemic complications had abnormal perfusion (p = 0.0005). Age at the time of surgery did not differ significantly (p = 0.234) between the patients with perfusion defects and those with normal study results. No significant difference was observed between the patients who had an A coronary pattern (left coronary artery originating from the left sinus and the right coronary artery originating from the right sinus, n = 47) and those who had a non-A coronary pattern (n = 22) (p = 1). The high rate for normality of exercise myocardial perfusion in our study suggests that myocardial perfusion gated-SPECT should be reserved for patients who have experienced perioperative ischemic complications or those with symptoms, at least during the first 10 years after the surgery.     

Colour stainability of indirect CAD–CAM processed composites vs. conventionally laboratory processed composites after immersion in staining solutions

Objectives

The aim of this study was to determine, by using a spectrophotometer device, the colour stainability of two indirect CAD/CAM processed composites in comparison with two conventionally laboratory-processed composites after being immersed 4 weeks in staining solutions such as coffee, black tea and red wine, using distilled water as control group.

Methods

Two indirect CAD/CAM composites (Lava Ultimate and Paradigm MZ100) and two conventionally laboratory-processed composites (SR Adoro and Premise Indirect) of shade A2 were selected (160 disc samples). Colour stainability was measured after 4 weeks of immersion in three staining solutions (black tea, coffee, red wine) and distilled water. Specimen's colour was measured each week by means of a spectrophotometer (CIE L*a*b* system). Statistical analysis was carried out performing repeated ANOVA measurements and Tukey's HSD test to evaluate differences in ΔE₀₀ measurements between groups; the interactions among composites, staining solutions and time duration were also evaluated.

Results

All materials showed significant discoloration (p < 0.01) when compared to control group. The highest ΔE₀₀ observed was with red wine, whereas black tea showed the lowest one. Indirect laboratory-processed resin composites showed the highest colour stability compared with CAD/CAM resin blocks.

Conclusions

CAD/CAM processed composites immersed in staining solutions showed lower colour stability when compared to conventionally laboratory-processed resin composites.

Clinical significance

The demand for CAD/CAM restorations has been increasing; however, colour stainability for such material has been insufficiently studied. Moreover, this has not been performed comparing CAD/CAM processed composites versus laboratory-processed indirect composites by immersing in staining solutions for long immersion periods.