Objectives In this study, we systematically assessed the diagnostic and prognostic value of absence of coronary artery calcification (CAC) in asymptomatic and symptomatic individuals. Background ...Presence of CAC is a well-established marker of coronary plaque burden and is associated with a higher risk of adverse cardiovascular outcomes. Absence of CAC has been suggested to be associated with a very low risk of significant coronary artery disease, as well as minimal risk of future events. Methods We searched online databases (e.g., PubMed and MEDLINE) for original research articles published in English between January 1990 and March 2008 examining the diagnostic and prognostic utility of CAC. Results A systematic review of published articles revealed 49 studies that fulfilled our criteria for inclusion. These included 13 studies assessing the relationship of CAC with adverse cardiovascular outcomes in 64,873 asymptomatic patients. In this cohort, 146 of 25,903 patients without CAC (0.56%) had a cardiovascular event during a mean follow-up period of 51 months. In the 7 studies assessing the prognostic value of CAC in a symptomatic population, 1.80% of patients without CAC had a cardiovascular event. Overall, 18 studies demonstrated that the presence of any CAC had a pooled sensitivity and negative predictive value of 98% and 93%, respectively, for detection of significant coronary artery disease on invasive coronary angiography. In 4,870 individuals undergoing myocardial perfusion and CAC testing, in the absence of CAC, only 6% demonstrated any sign of ischemia. Finally, 3 studies demonstrated that absence of CAC had a negative predictive value of 99% for ruling out acute coronary syndrome. Conclusions On the basis of our review of more than 85,000 patients, we conclude that the absence of CAC is associated with a very low risk of future cardiovascular events, with modest incremental value of other diagnostic tests in this very low-risk group.
Objectives This study aimed to test the hypothesis that metabolic activity within periodontal tissue (a possible surrogate for periodontal inflammation) predicts inflammation in a remote ...atherosclerotic vessel, utilizing18 F-fluorodeoxyglucose (FDG) positron emission tomography (PET) imaging. Background Several lines of evidence establish periodontal disease as an important risk factor for atherosclerosis. FDG-PET imaging is an established method for measuring metabolic activity in human tissues and blood vessels. Methods One hundred twelve patients underwent FDG-PET imaging 92 ± 5 min after FDG administration (13 to 25 mCi). Periodontal FDG uptake was measured by obtaining standardized uptake values from the periodontal tissue of each patient, and the ratio of periodontal to background (blood) activity was determined (TBR). Standardized uptake value measurements were obtained in the carotid and aorta as well as in a venous structure. Localization of periodontal, carotid, and aortic activity was facilitated by PET coregistration with computed tomography or magnetic resonance imaging. A subset of 16 patients underwent carotid endarterectomy within 1 month of PET imaging, during which atherosclerotic plaques were removed and subsequently stained with anti-CD68 antibodies to quantify macrophage infiltration. Periodontal FDG uptake was compared with carotid plaque macrophage infiltration. Results Periodontal FDG uptake (TBR) is associated with carotid TBR (R = 0.64, p < 0.0001), as well as aortic TBR (R = 0.38; p = 0.029). Moreover, a strong relationship was observed between periodontal TBR and histologically assessed inflammation within excised carotid artery plaques (R = 0.81, p < 0.001). Conclusions FDG-PET measurements of metabolic activity within periodontal tissue correlate with macrophage infiltration within carotid plaques. These findings provide direct evidence for an association between periodontal disease and atherosclerotic inflammation.
Cardiac magnetic resonance (CMR) has been shown to predict left ventricular (LV) recovery in patients after acute ST-segment elevation myocardial infarction. The purpose of this investigation was to ...determine the relative values of infarct transmurality and microvascular obstruction (MVO) using delayed enhancement CMR to predict LV recovery. We studied 17 patients (mean age 60 ± 10 years, 14 men) presenting with first acute ST-segment elevation myocardial infarction treated with primary percutaneous coronary intervention who underwent CMR within 6 days after presentation and again at 6 months. In total 680 myocardial segments were evaluated, of which 267 (39%) demonstrated delayed hyperenhancement (DHE) and 116 (18%) demonstrated MVO. Unadjusted odds ratio (OR) for any improvement in regional LV function with increasing DHE category (<50%, 51% to 75%, >75% transmurality) was 0.20 (95% confidence interval CI 0.13 to 0.30, p <0.0001), whereas it was 0.40 (95% CO 0.28 to 0.55, p <0.0001) with increasing MVO category (0, <50th, >50th percentile). However, when coadjusted together, the relation remained robust with regard to degree of transmurality of DHE (OR 0.21, 95% CI 0.13 to 0.36, p <0.0001), but the relation was lost for MVO (OR 0.90, 95% CI 0.58 to 1.40, p = 0.64). In conclusion, when using the delayed enhancement technique for assessment of DHE and MVO, degree of infarct transmurality appears to be a more powerful predictor of LV recovery by CMR.
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