Diagnostic accuracy of Visipaque enhanced coronary computed tomographic angiography: a prospective multicenter trial.

BACKGROUND: Although several studies have shown promise for noninvasive angiography by coronary computed tomographic angiography (CCTA), few prospective multicenter trials have been conducted. This study evaluated the diagnostic accuracy of Visipaque enhanced CCTA to detect obstructive coronary stenosis compared with quantitative coronary angiography (QCA). PATIENTS AND METHODS: Three sites prospectively enrolled 77 patients (58.1% men, 54 years) with chest pain referred for invasive coronary angiography (ICA). Patients underwent CCTA (Lightspeed VCT/Visipaque 320) before ICA. CCTAs were graded on a 15-segment American Heart Association model by a CCTA core lab with blinded readers for the presence of obstructive stenosis (>50% or >70%); ICAs were independently graded for %stenosis by QCA, considered the reference standard. The efficacy of CCTA was assessed including all vessel segments for per-patient and per-vessel analyses. RESULTS: A total of 46 more than 50% stenoses in 27 (35%) patients, and 31 more than 70% stenoses in 20 (26%) patients, were identified by QCA. Per-patient and per-vessel efficacy of CCTA compared with QCA yielded sensitivities of 85% and specificities of 90 and 95%, respectively. CONCLUSION: This study shows the high accuracy of CCTA to reliably detect more than 50% and more than 70% stenoses in low-probability to intermediate-probability chest pain patients being referred for ICA. The high negative predictive values observed (92-100%) indicate that CCTA is also an effective noninvasive alternative to exclude obstructive coronary stenosis.

Motivational effects of coronary artery calcium scores on statin adherence and weight loss.

AIM: The aim of this study was to assess the effect on adherence to statin therapy and assess the effect of beneficial changes in behavior that resulted in weight loss in patients who underwent coronary artery calcium (CAC) scoring with cardiac computed tomography. BACKGROUND: Despite convincing data demonstrating the benefits of HmGCoA inhibitors for both primary and secondary prevention of coronary heart disease, they remain underused. Also, despite convincing data demonstrating the benefits of weight loss for both primary and secondary prevention of coronary heart disease, it remains difficult to motivate behavioral changes resulting in weight loss. In this study, we assess whether higher CAC scores are associated with increased compliance with statin medication and whether higher CAC scores are associated with beneficial lifestyle behaviors resulting in weight loss. METHODS: We retrospectively analyzed patients that had undergone baseline CAC testing and returned for a follow-up scan. All patients had weight documented and were administered a questionnaire regarding compliance to medications. The primary endpoint was measurable weight loss between visit one and visit two and the self-reported compliance to statin use. RESULTS: The study population with data regarding statin compliance consisted of 2608 individuals (72% men, mean age 58±8 years) who were followed for a mean of 4.1±3.2 years after an initial CAC scan. Overall, statin compliance was lowest (27.4%) among those with CAC=0, and gradually increased with higher CAC scores (1-99, 39.2%; 100-399, 53.6%; ≥400, 58.8%; P<0.001 for trend). In the group analyzed for weight loss the study population consisted of 1078 individuals (68% men, mean age 60±8 years) who were followed for a mean of 4.1±3.2 years after an initial CAC scan. CONCLUSION: Overall, behavioral modification resulting in weight loss was lowest (19.8%) among those with CAC=0, and gradually increased with higher CAC scores (1-99, 23.4%; 100-399, 30.8%; ≥400, 33.6%; P<0.001 for trend). In addition to being a robust risk stratification tool, a higher rate of adherences with statin therapy was observed in patients with higher CAC scores.

Coronary calcium: new insights, recent data, and clinical role.

Calcium artery calcium (CAC) scoring has become an integral part in the era of preventive cardiology, it has been extensively studied and been validated as a powerful tool for cardiovascular risk assessment in conjunction with other traditional well established scoring systems such as Framingham risk score. In addition, CAC testing has found its way into emergency department algorithms assessing low to intermediate risk patients presenting with chest pain, this strategy was recently adopted by the UK NICE guidelines, confidently ruling out cardiac origin of chest pain. Several studies have demonstrated that risk assessment using CAC was motivational to patients leading to better adherence to their preventive practices as well as to medications. Accordingly, this test has several recommendations for use by national and international guidelines.

CTA in the evaluation of acute chest pain syndromes. Should more widespread use be advocated?

INTRODUCTION: With the advent of CT more than 3 decades ago, we have seen rapid evolution of this technology, so that we are now able to noninvasively accurately image the coronary arterial tree. This has opened up a debate as to the role of this imaging modality in our day-to-day evaluation of acute coronary syndromes. Much recent literature has focused on whether in the acute setting this modality should be incorporated into current evaluation and treatment guidelines. AREAS COVERED: A comprehensive review of a literature illustrating the utility of CTA in the acute care setting is presented. The paper goes on to address the benefits and challenges of implementation of CTA in the evaluation of acute chest pain syndromes. Alternative guidelines and insights on future directions are presented. EXPERT OPINION: In this current era where CAD, and more specifically acute chest pain syndromes, remains as a large part of ED visits and also healthcare costs, CTA will play an important role in the diagnosis and treatment of individuals. It remains only a matter of time when this will be implemented in our guidelines, in light of the recent literature and ever improving CTA protocols.

Effect of patient visualization of coronary calcium by electron beam computed tomography on changes in beneficial lifestyle behaviors.

Despite convincing data demonstrating the benefits of aspirin (ASA), exercise, and dietary changes for both primary and secondary prevention of coronary heart disease, they remain underused. In this study, we assess whether higher coronary artery calcium (CAC) scores determined by electron beam computed tomography (EBCT) are associated with beneficial lifestyle behaviors in asymptomatic individuals. A total of 980 asymptomatic patients referred for EBCT risk assessment by their primary physician were sent a survey questioning them about health behaviors. We evaluated long-term ASA utilization, exercise, and dietary changes based on CAC using multivariable analysis. The study population consisted of 980 individuals (78% men, mean age 60 +/- 8 years) who were followed for a mean of 3 +/- 2 years after an initial EBCT scan. Overall, ASA initiation was lowest (29%) among those with CAC = 0, and gradually increased with higher CAC scores (1 to 99, 55%; 100 to 399, 61%; > or =400, 63%; p <0.001 for trend). Similarly, dietary changes and exercise were lowest (33% and 44%, respectively) among those with CAC = 0 and gradually increased with higher CAC scores (1 to 99, 40%; 100 to 399, 58%; > or =400, 56%; p <0.001 for trend for dietary changes; and 1 to 99, 62%; 100 to 399, 63%; > or =400, 67%; p <0.001 for trend for exercise). In multivariable analysis, greater baseline CAC was strongly associated with initiation of ASA therapy, dietary changes, and increased exercise. In conclusion, in addition to risk stratification of asymptomatic individuals, determination of CAC may also improve utilization of ASA therapy and behavioral modification.

Right precordial leads and lead aVR at exercise electrocardiography: does it change test results?

BACKGROUND: A recent study on exercise testing (ET) suggested that ST-segment changes in the right precordial leads (RPL) may increase its sensitivity substantially. However, this study looked at a highly selected population of patients who all underwent thallium-201 scintigraphy and coronary angiography. The present study evaluated the clinical utility of ST-segment changes in the RPL and lead aVR in an unselected population of patients undergoing ET. METHODS: A total of 906 consecutive patients who received ET were included in the study. ET was done using the Bruce Protocol with a 12-lead electrocardiogram (ECG) substituting V(4)R and V(6)R for V(1) and V(6). Leads V(1) and V(6) were selected for omission as these two leads hardly ever manifest changes in isolation. Substituting two leads would obviate the need for a more complex recording system, thus improving clinical utility. RESULTS: On the basis of horizontal/downsloping ST-segment depression (STD) of 1.0 mm or more (the usually accepted criterion for a positive ET), 159 (17.5%) patients had a positive ET. In those patients with a negative ET (545 patients), 4 patients (0.7%) manifested STD and 5 patients (0.9%) manifested ST-segment elevation (STE) in leads V(4)R and/or V(6)R, respectively. Of note, 44.7% of the positive ET group had STE in lead aVR. CONCLUSION: The use of ST-segment changes in RPL during exercise stress testing does not appreciably change the test results of a standard ET. If one was to consider an additional marker, STE in aVR may be more useful, as it shows a stronger correlation with positive tests and does not require the recording of additional leads.

Visualizing coronary calcium is associated with improvements in adherence to statin therapy.

BACKGROUND: Many patients lack motivation to control cardiovascular risk factors and clinicians have long sought ways to activate apathetic patients. Despite significant and consistent data on the benefits of lipid-lowering agents to reduce cardiovascular events, adherence and utilization of these agents remains low. We evaluated whether visualization of coronary calcium would positively affect patients' adherence rates. METHODS: We evaluated patients who underwent electron beam tomography (EBT) coronary calcium evaluation at least 1 year prior with a survey questioning them about health behaviors. Patients filled out baseline and follow-up questionnaires relating to lifestyle modifications, including statin utilization, diet, exercise, tobacco cessation and vitamin/antioxidant utilization. RESULTS: The study population consisted of 505 individuals on statin therapy on baseline who were followed for a mean of 3 +/- 2 years. Overall the statin compliance was lowest (44%) among those with CAC score in the first quartile (0-30), whereas 91% of individuals with baseline CAC score in the fourth quartile (>or= 526) adhered to statin therapy. In multivariable analysis, after adjusting for cardiovascular risk factors, age, and gender, higher baseline CAC scores were strongly associated with adherence to statin therapy. CONCLUSIONS: In addition to risk stratification for the asymptomatic person, patients visualizing coronary artery calcium may improve utilization and adherence to lipid-lowering therapy. Outcome studies and randomized trials need to be done to quantify the true value and cost-effectiveness of this approach.