Search PubMed⌕ Search

Biomedical subjects

Matthew J Budoff

Publications and source records attributed to Matthew J Budoff.

At least 73 records · Page 4Linked to original sources
PubMed2004

Tracking progression of heart disease with cardiac computed tomography.

The ability to follow changes in atherosclerotic plaque burden over time should provide an accurate measure of efficacy for different cardiovascular therapies. Coronary calcifications are associated with atherosclerotic coronary artery plaque, and the amount of coronary calcifications has been shown to correlate with the overall coronary plaque burden. The presence and extent of coronary calcifications can be assessed noninvasively by monitoring the progression of coronary calcification with electron beam tomography. With annual progression rates of 22% to 52% and a median interscan variability of only 5% to 8%, this technology provides an opportunity to monitor patients to assess the clinical efficacy of medical therapies in studies as short as 1 year. Several studies have demonstrated that the successful pharmacologic reduction of low-density lipoprotein cholesterol significantly mitigated the progression of the calcium score. Studies using serial computed tomographic scans indicate that the annual progression of coronary calcium varies between 30% and 50% in symptomatic or high-risk individuals and from 0% to 20% in patients treated effectively with lipid-lowering medication. An increased rate of progression of coronary calcium seems to indicate a substantially increased risk for adverse cardiac events, suggesting that this modality can be used to monitor the efficacy of therapy.

Calcinosis↗
PubMed2003

Clinical utility of computed tomography and magnetic resonance techniques for noninvasive coronary angiography.

OBJECTIVE: The purpose of this study was to provide a comprehensive review of the literature relating to electron beam angiography (EBA), magnetic resonance angiography, and spiral computed tomography, currently the three most promising noninvasive methods to visualize obstructions in the coronary tree. BACKGROUND: Given the high costs and invasiveness of coronary angiography, there is increased interest in noninvasive coronary angiography, which has made great strides to become a clinically useful tool to augment conventional coronary angiography (CCA). METHODS: MEDLINE searches were performed to include all articles related to noninvasive angiography utilizing either magnetic resonance imaging (MRI), multi-row detector spiral computed tomography (MDCT), and electron beam tomography (EBT). Weighted analysis was performed to define the published sensitivity and specificity for each technique. RESULTS: Electron beam angiography (EBA) provides an overall sensitivity of 87% and specificity of 91% for the detection of obstructive coronary artery disease (CAD). Four-level MDCT data demonstrated an overall sensitivity of 59% and specificity of 89%, with higher accuracy in two recent studies of 16-level detector devices. Magnetic resonance angiography demonstrated sensitivity for detection of obstructive CAD of 77% and specificity of 71%. CONCLUSIONS: Noninvasive coronary angiography is a rapidly developing technique and currently not an alternative to CCA in all cases. All three methods are currently used clinically in certain centers with appropriate expertise. Selective use should prove both cost-effective and provide a safer, less-invasive method for patients to determine the need for medical versus revascularization therapy.

Coronary Disease↗
PubMed2003

Comparison of frequency of coronary artery calcium in healthy Hispanic versus non-Hispanic white men by electron beam computed tomography.

We recently demonstrated in subjects referred for the evaluation of cardiovascular disease that coronary atherosclerosis and coronary artery calcium (CAC) were reduced in Hispanics compared with non-Hispanic whites (NHWs). We now evaluate whether this ethnic disparity is present in a unselected healthy cohort of men. Despite the apparently worse risk factor profile, mean and median levels of CAC trended lower in Hispanic men, and the distribution of CAC scores differed from that of NHW (p <0.05), with fewer Hispanic subjects having CAC scores that are generally equated with extensive atherosclerotic burden (>400). These results demonstrate that healthy Hispanic men have reduced CAC compared with age-matched NHW men and this occurs despite evidence for a worse cardiovascular risk profile.

Aged↗
PubMed2003

Usefulness of aortic valve calcium scores by electron beam computed tomography as a marker for aortic stenosis.

This study was undertaken to determine whether aortic valve calcium (AVC) scores measured by electron beam tomography can identify patients with echocardiographically defined aortic stenosis. Electron beam tomography is increasingly being used to detect coronary artery calcium. AVC can also be measured on electron beam tomographic (EBT) scans obtained to screen for coronary calcium. Whether EBT AVC scores correlate with the presence of aortic stenosis, as assessed by echocardiography, is unknown. Results of this study suggest that AVC scores should be calculated routinely for coronary calcium screening EBT scans, and that patients with Agatston AVC scores above a certain level (e.g., >150) should be referred for echocardiography.

Aortic Valve↗
PubMed2003

Valvular and thoracic aortic calcium as a marker of the extent and severity of angiographic coronary artery disease.

BACKGROUND: The presence of calcified extracoronary structures as a useful indicator of underlying coronary artery disease (CAD) has not yet been established. The purpose of this study was to evaluate whether valvular and thoracic aortic calcification is associated with obstructive CAD. METHODS: We evaluated 99 patients who underwent both coronary angiography and electron beam tomography (EBT) coronary scanning. We identified the presence, absence, and amount of calcification in the aortic valve (AVC), mitral annulus (MAC), descending aorta (DAC), and ascending aorta (AAC). The extent of CAD was graded according to the number of vessels diseased (VD). RESULTS: Patients with multivessel disease (MVD) had a higher proportion of DAC. The presence of DAC significantly increased the specificity of EBT to detect CAD (58% with a calcium score >0 to 88% for calcium score>0 and DAC >0, P <.001). Both AAC and DAC were associated with a significantly higher rate of MVD in women (DAC, 63% in MVD vs 19% without, P <.01.; AAC, 65% vs 22%, P <.05). MAC had no relationship to either stenosis severity or the presence of obstructive CAD. AVC was the strongest predictor of the severity of CAD and predicted the presence of 3-vessel disease. CONCLUSION: AVC and thoracic aortic calcification as detected with EBT are associated with the angiographic extent and severity of CAD and add incremental diagnostic value to the coronary artery calcium score. MAC does not add incremental value.

Adult↗
PubMed2003

Electron beam CT versus helical CT scans for assessing coronary calcification: current utility and future directions.

BACKGROUND: Traditional risk factors for coronary artery disease predict the development of atherosclerosis; however, their ability to identify individual patients at risk of events is limited. METHODS: Coronary artery calcium (CAC) is a specific marker of atherosclerosis. It can be visualized and measured noninvasively by various imaging techniques, which may add incremental prognostic value to conventional coronary factors. RESULTS: The field of atherosclerosis imaging has expanded rapidly in the last decade, and technologies such as electron-beam computed tomography (EBCT) have contributed to our understanding of the prevalence of occult coronary artery disease and its consequences. Other modalities have been previously limited by the decreased temporal and spatial resolution and slower acquisition. Recent advances in helical CT (HCT) imaging with the development of multiple row detectors CT (MDCT) and improvements in the temporal resolution have renewed clinicians' interests in using this modality to evaluate CAC, although the scores obtained with MDCT may differ somewhat from those obtained with the EBCT technology. This study critically analyzes the literature comparing the utility of EBCT and HCT in detecting coronary calcium to identify individuals at increased risk for future coronary events. CONCLUSIONS: MDCT is a promising tool for coronary calcium scoring; however, more studies are needed comparing EBCT and MDCT, especially at lower CAC levels.

Calcinosis↗
PubMed2003

Measures of brachial artery distensibility in relation to coronary calcification.

BACKGROUND: Brachial artery measures of arterial distensibility have been demonstrated to be independent risk factors for development of heart disease. These measures have been suggested as reflecting the endothelial function or atherosclerotic burden; however, they have not been compared with levels of subclinical atherosclerosis. This study sought to compare measures of brachial artery distensibility to subclinical atherosclerosis as measured by electron beam tomography (EBT). METHODS: Brachial artery pulse waveform data were collected using the DynaPulse 2000A (Pulse Metric, Inc., San Diego, CA). Distensibility measurements were taken on 201 healthy adults and compared with levels of coronary artery calcification (CAC) as measured by EBT. Laboratory values, risk factors, blood pressure (BP), and heart rate measurements were also obtained. We then compared the results of the brachial artery measurements to measures of standard risk factors and CAC. RESULTS: Multivariate analysis was performed, revealing that brachial artery measures were the strongest predictor of CAC. For women, brachial artery (BA) resistance was the strongest independent predictor of log CAC score (r = 0.373, P =.004). For men, BA distensibility was the only independent predictor of calcium scores (P =.012). We then divided the patients into quintiles of calcium score. Patients in the top quintile had a mean BA distensibility that was significantly higher than those of the lowest quintile (P =.02). CONCLUSIONS: Stiffer vessels with decreased distensibility were seen in subjects with higher levels of coronary artery calcium. Therefore, noninvasive measures of distensibility are useful in measuring subclinical vascular changes related to arteriosclerosis. This noninvasive measure might provide a simple and inexpensive method to identify patients with significant atherosclerotic burden.

Age Factors↗
PubMed2003

Aortic atherosclerosis detected with electron-beam CT as a predictor of obstructive coronary artery disease.

RATIONALE AND OBJECTIVES: Several studies have demonstrated an association between coronary and aortic atherosclerosis. Aortic atherosclerosis is easily quantified by means of electron-beam computed tomography (CT). The aim of this study was to evaluate the usefulness of measurement of aortic atherosclerosis with electron-beam CT as an independent predictor of obstructive coronary artery disease (CAD). MATERIALS AND METHODS: Ninety-seven patients (67 men, 30 women; mean age, 61 years +/- 12) were enrolled and underwent electron-beam CT with and without contrast material. Coronary artery calcification was quantified with nonenhanced electron-beam CT by means of Agatston score. CAD was defined as luminal narrowing of the coronary artery by at least 70%, as measured with electron-beam angiography. Aortic atherosclerosis was quantified by measuring raised lesions of the aortic wall (plaque) and wall thickening (volume and thickness) in the midportion of the descending thoracic aorta (10 contiguous sections), as depicted at contrast material-enhanced CT angiography. RESULTS: Aortic plaque and calcification were detected only in patients who were at least 58 years old. The presence of aortic plaque was predictive of obstructive CAD, independent of coronary artery calcification. The sensitivity of aortic plaque (raised lesions) for obstructive CAD was 89% in patients at least 58 years old, and the specificity was 63%. Aortic calcification had a sensitivity of 56% and a specificity of 72% for diagnosis of obstructive CAD. CONCLUSION: This study demonstrated that aortic plaque detected with contrast-enhanced electron-beam CT was a more consistent predictor of obstructive CAD than other independent aortic variables. Aortic calcification depicted on nonenhanced CT images was highly specific for obstructive CAD.

Adult↗
PubMed2003

Measurement of the RT interval on ECG records during electron-beam CT.

RATIONALE AND OBJECTIVES: The R wave of the electrocardiogram is used widely as a trigger for cardiac imaging. This study was designed to determine the optimal interval between the R wave and end systole for triggering of electron-beam computed tomography (CT) in a group of patients with various heart rates who are undergoing assessment for coronary artery calcification. MATERIALS AND METHODS: A total of 862 consecutive asymptomatic patients referred for screening with electron-beam CT for coronary artery calcification were enrolled in the study. Patients' R-R, RT, and PR intervals were measured by using the software of the CT console computer. Correlation coefficients were computed and linear regression analyses were performed for all intervals measured. Results were analyzed according to patient age (three subgroups), sex (two subgroups), and heart rate (nine subgroups). Separate formulas for calculating the length of RT intervals in men and in women were developed. RESULTS: After correction for heart rate, a significant difference was found in mean RT and PR intervals between women and men, with the mean intervals in women being longer (P < .001). No significant difference was found in these intervals within the three age-defined subgroups (< or = 40, 41-60, and >60 years; P > .05). However, significant negative correlations were found between heart rates and the lengths of all measured intervals. The results of statistical analysis indicate that most of the variation in the R-R interval with different heart rates occurred in diastole and that the duration of systole was relatively constant. CONCLUSION: For optimal cardiac imaging, triggering should take place in late systole, avoiding the RT interval variability that occurs in diastole.

Adult↗
PubMed2003

Comparison of LV mass and volume measurements derived from electron beam tomography using cine imaging and angiographic imaging.

PURPOSE: To estimate the variation of left ventricular (LV) mass and volume measurement with cine and angiography by electron beam tomography (EBT). METHOD AND MATERIALS: Sixty-three consecutive patients (41 men, 22 women; age range 46-91) referred for cardiac imaging for clinical indications underwent cine and coronary artery electron beam angiography (EBA) studies on the same day. The cine images consisted of 144 images (12 slices/level x 12 levels), taken 12 frames/s for a full cardiac cycle. The EBA images consisted of 50-70 slices triggered at end-systole, with an acquisition time of 100 ms/slice. Slice thickness was 8 mm for the cine images and 1.5 mm for the EBA images. A total volume of 120-180 ml of nonionic contrast was used for each subject. The LV mass (myocardial tissue volume), LV cavity volume and total LV volume (tissue + cavity) measurements were completed using the software from the EBT computer console (G.E., S. San Francisco, CA). RESULTS: The LV mass, cavity volume and total LV volumes at end-systole were 124.11 g, 45.66 and 163.86 ml when derived from the cine images and 130.74 g, 41.31 and 165.82 ml when derived from the EBA images. There were no significant differences between the cine and EBA-derived measurements, however the EBA-derived measurements showed slightly larger LV mass (mean 6.63 g), smaller cavity volume (mean -4.35 ml) and larger total LV volume (mean 1.96 ml, all p > 0.05) than did the cine-derived measurements. Based on case-by-case observations, these differences appear to be related to the higher spatial resolution of the thinner EBA images which allows better discrimination between papillary and trabecular muscle and LV. This leads to slightly smaller cavity size estimations and greater LV mass measurements. There was significant correlation between cine and EBA-derived measurements. Formulas were developed for relating the measurements made from the two modalities as follows: For LV mass: EBA value = 0.91 x cine value + 17.09, R = 0.95, p < 0.001; For LV cavity volume: EBA value = 1.06 x cine value - 6.91, R = 0.96, p < 0.001; For total LV volume: EBA value = 0.98 x cine value + 5.09 in ml, p < 0.001. The mean differences in measurements using the two modalities were 8.1, 18.2 and 6.5% for LV mass, LV cavity volume and total LV volume, respectively. CONCLUSION: Both cine and EBA images were useful for measuring LV mass and volume with good intertest agreement. Cardiac volume and mass measurements derived from cine EBT studies probably slightly underestimate LV mass and overestimate LV volume.

Aged↗
PubMed2003

Relation of coronary artery calcium to left ventricular mass and geometry in patients with essential hypertension.

BACKGROUND: There is a close relationship between left ventricular hypertrophy and cardiovascular diseases that are observed in hypertension. In this study, the amount of coronary artery calcium, which is an indicator of atherosclerosis, has been measured and its relationship with left ventricular hypertrophy and geometry and other traditional risk factors has been investigated. DESIGN: A total of 249 (104 females, 145 males) hypertensive asymptomatic patients, without diabetes with an average age of 55.09 +/- 11.32 years were included in the study. Left ventricular mass of the patients was measured with M-mode echocardiography and coronary artery calcium with electron beam tomography. The average age of the patients who had calcium in their coronary arteries (CAC+) was 59.99 +/- 9.85 years, and the average age of the ones without calcium (CAC-) was 49.29 +/- 10.19 years. RESULTS: Mean left ventricular mass index (LVMI) was measured as 130.18 +/- 43.24 g/m2 in CAC+ patients and as 108.47 +/- 29.09 g/m2 in CAC- patients. These two groups did not differ in terms of the parameters such as total cholesterol, high-density lipoprotein cholesterol (HDL-C), low-density lipoprotein cholesterol (LDL-C), triglyceride and uric acid levels, the presence of early coronary disease in the family and smoking. Patients who had calcium in their coronary arteries (CAC+) were more obese (P < 0.004). In the logistic regression analysis, we demonstrated that body mass index and age were the factors affecting the presence and amount of calcification seen in coronary arteries in left ventricular hypertrophy. In the analysis performed by taking left ventricular hypertrophy into consideration, mean calcium scores of the patients with normal remodeling, concentric remodeling, eccentric hypertrophy and concentric hypertrophy were 50.9 +/- 187.4, 68.6 +/- 159.3, 92.2 +/- 160.2 and 315.4 +/- 760.6, respectively. In the patients with concentric left ventricular hypertrophy (LVH), the mean calcium scores of the coronary arteries and the rate of being CAC+ were significantly high, although these patients were also older. After linear regression, the relationship between concentric LVH and coronary artery calcium (CAC) was still significant. CONCLUSION: In conclusion, left ventricular hypertrophy that is observed in hypertension is an important risk factor for sub-clinical atherosclerosis. Concentric left ventricular hypertrophy is a more important risk factor than other geometric patterns.

Adult↗
PubMed2003

Sensitivity to detect small coronary artery calcium lesions with varying slice thickness using electron beam tomography.

RATIONALE AND OBJECTIVE: To estimate the sensitivity to find small coronary artery calcium lesions with use of different slice widths with electron beam tomography. MATERIALS AND METHODS: Two studies were performed. Study 1 utilized double scanning of a stationary cork phantom with three different slice thickness (1.5, 3, and 6 mm). Fifty different calcific lesions (all <20 mm2 in area) fitted in 10 cork coronary arteries were utilized. The calcium foci area, peak value and score were measured and compared. In group 2, 30 patients underwent coronary artery calcium (CAC) screen studies. Each patient was scanned with both 3-mm and 6-mm scan widths in a same study time. Lesions with < 20 mm2 of area of CAC were measured on both 3-mm and 6-mm images. The mean and peak Hounsfield unit measure, and Agatston score were compared between both images. RESULTS: In the cork study, the sensitivity to detect small calcium foci were 96% (48/50), 82% (41/50), and 34% (17/50) in images with 1.5-, 3-, and 6-mm slice thickness, respectively. There is a smaller value in mass, and calcium volume in 6-mm images than 1.5-mm and 3-mm images ( P< 0.001). There was no significant difference between the true value and measured value from 1.5-mm and 3-mm images. In the human study, 18 (30%) of 60 CAC lesions with an area < 20 mm2 defined on 3 mm images were not visible on 6-mm images. Sensitivity of small lesions (P< 5 mm2) was 48% using 6-mm slices. There was a smaller value in CAC area, mean and peak Hounsfield units and score measured from 6-mm images, as compared with 3 mm slices ( P< 0.05). CONCLUSION: Thinner slice imaging has a higher sensitivity to detect small calcium focus. There was no significant change in score between 3 mm and 1.5 mm on the cork phantom study. However, the use of 6-mm slices should be discouraged, as this protocol both underestimates calcific mass and misses a significant number of calcific lesions in both a phantom and human study.

Calcinosis↗
PubMed2002

Continuous probabilistic prediction of angiographically significant coronary artery disease using electron beam tomography.

BACKGROUND: We sought to incorporate electron beam tomography-derived calcium scores in a model for prediction of angiographically significant coronary artery disease (CAD). Such a model could greatly facilitate clinical triage in symptomatic patients with no known CAD. METHODS AND RESULTS: We examined 1851 patients with suspected CAD who underwent coronary angiography for clinical indications. An electron beam tomographic scan was performed in all patients. Total per-patient calcium scores and separate scores for the major coronary arteries were added to logistic regression models to calculate a posterior probability of the severity and extent of angiographic disease. These models were designed to be continuous, adjusted for age and sex, corrected for verification bias, and independently validated in terms of their incremental diagnostic accuracy. The overall sensitivity was 95%, and specificity was 66% for coronary calcium to predict obstructive disease on angiography. With calcium scores >20, >80, and >100, the sensitivity to predict stenosis decreased to 90%, 79%, and 76%, whereas the specificity increased to 58%, 72%, and 75%, respectively. The logistic regression model exhibited excellent discrimination (receiver operating characteristic curve area, 0.842+/-0.023) and calibration (chi2 goodness of fit, 8.95; P=0.442). CONCLUSIONS: Electron beam tomographic calcium scanning provides incremental and independent power in predicting the severity and extent of angiographically significant CAD in symptomatic patients, in conjunction with pretest probability of disease. This algorithm is most useful when applied to an intermediate-risk population.

Adult↗
PubMed2002

HMG CoA reductase inhibitor (statin) and aortic valve calcium.

There is no known pharmacological therapy for calcific aortic valvular sclerosis or stenosis. Because leaflet calcification occurs in areas of lipoprotein deposition, we hypothesised that 3-hydroxy-3-methylglutaryl-coenzyme A (HMG COA) reductase inhibitors (statins) might slow aortic valve calcium (AVC) accumulation. We retrospectively identified 65 patients who had undergone two electron-beam computed tomography scans at a mean (SD) interval of 2.5 (1.6) years. 28 (43%) patients were receiving statins. Patients who were treated with statins had a 62-63% lower median rate of AVC accumulation (p=0.006) and 44-49% fewer statin patients had definite AVC progression (p=0.043). These findings suggest that statins may decrease AVC accumulation.

Aortic Valve↗
PubMed2002

Ethnic differences in coronary atherosclerosis.

OBJECTIVES: The study was done to evaluate whether ethnic differences exist in the prevalence of coronary artery calcification (CAC), and to determine whether differences in calcification correlate with the degree of coronary obstruction. BACKGROUND: Electron beam tomography (EBT) can be used to quantitate the amount of CAC and assist in prognostication of future cardiac events. It is unclear whether ethnic differences in coronary mortality are related to differences in the prevalence of coronary obstruction and CAC. METHODS: A total of 782 symptomatic subjects underwent both EBT and angiography. A 50% luminal narrowing defined an angiographic obstruction. RESULTS: We observed substantial ethnic differences in prevalence of both CAC and angiographic stenosis. In whites (n = 453), prevalence of CAC (score >0) was 84%, and significant obstruction on angiogram was 71%. Compared with whites, blacks (n = 108) had a significantly lower prevalence of CAC (62%, p < 0.001) and angiographic disease (49%, p < 0.01). Hispanics (n = 177) also had a lower prevalence of CAC (71%, p < 0.001) and angiographic obstruction (58%, p < 0.01). Asians (n = 44) were not significantly different in regard to CAC (73%, p = 0.06) or angiographic stenosis (64%, p = 0.30). These ethnic differences remained after simultaneously controlling (by use of multiple logistic regression) for age, gender and cardiac risk factors. CONCLUSIONS: As compared with whites, blacks and Hispanics had significantly lower prevalence of CAC and obstructive coronary disease. Ethnic differences in risk-factor profiles do not explain these differences. This study demonstrated that whites have a higher atherosclerotic burden than blacks and Hispanics, independent of risk-factor differences among symptomatic patients referred for angiography.

Adult↗