Ammar Sarwar

Publications of Ammar Sarwar

• Use of 100 kV versus 120 kV in cardiac dual source computed tomography: effect on radiation dose and image quality.

  Authors: Ron Blankstein, Michael A Bolen, Rodrigo Pale, Meagan K Murphy, Amar B Shah, Hiram G Bezerra, Ammar Sarwar, Ian S Rogers, Udo Hoffmann, Suhny Abbara, Ricardo C Cury, Thomas J Brady

  The international journal of cardiovascular imaging. 04/2011; 27(4):579-86.

  To evaluate the effective radiation dose and image quality resulting from use of 100 vs. 120 kV among patients referred for cardiac dual source CT exam (DSCT). Prospective data was collected on 294To evaluate the effective radiation dose and image quality resulting from use of 100 vs. 120 kV among patients referred for cardiac dual source CT exam (DSCT). Prospective data was collected on 294 consecutive patients referred for DSCT. For each scan, a physician specializing in cardiac CT chose all parameters including tube current and voltage, axial versus helical acquisition, and use of tube current modulation. Lower tube voltage was selected for thinner patients or when lower radiation was desired for younger patients, particularly females. For each study, image quality (IQ) was rated on a subjective IQ score and contrast (CNR) and signal-to-noise (SNR) ratios were calculated. Tube voltage of 100 kV was used for 77 (26%) exams while 120 kV was used for 217 (74%) exams. Use of 100 kV was more common in thinner patients (weight 166 lbs vs. 199 lbs, P < .001). The effective radiation dose for the 100 and 120 kV scans was 8.5 and 15.4 mSv respectively. Among scans utilizing 100 and 120 kV, there was no difference in exam indication, use of beta blockers, heart rate, scan length and use of radiation saving techniques such as prospective ECG triggering and tube current modulation. The IQ score was significantly higher for 100 kV scans. While 100 kV scans were found to have higher image noise then those utilizing 120 kV, the contrast-to-noise and signal-to-noise were significantly higher (SNR: 9.4 vs. 8.3, P = .02; CNR: 6.9 vs. 6.0, P = .02). In selected non-obese patients, use of low kV results in a substantial reduction of radiation dose and may result in improved image quality. These results suggest that low kV should be used more frequently in non-obese patients.

• Quantification of coronary stenosis by dual source computed tomography in patients: a comparative study with intravascular ultrasound and invasive angiography.

  Authors: Gudrun Feuchtner, Ricardo Loureiro, Hiram Bezerra, Jose A Rocha-Filho, Ammar Sarwar, Tobias Pflederer, Mohamed Marwan, Milena Petranovic, Christopher O Raffel, Thomas B Brady, Ik-Kyung Jang, Stephan Achenbach, Ricardo C Cury

  European journal of radiology. 01/2011; 81(1):83-8.

  To determine the accuracy of dual-source CT (DSCT) to quantify coronary stenosis compared to intravascular ultrasound (IVUS) and quantitative coronary angiography (QCA). 21 patients (23 vessels) wereTo determine the accuracy of dual-source CT (DSCT) to quantify coronary stenosis compared to intravascular ultrasound (IVUS) and quantitative coronary angiography (QCA). 21 patients (23 vessels) were examined with DSCT, IVUS and invasive coronary angiography. Coronary minimal luminal diameter (MLD) and area (MLA) were measured in cross-sectional multi-planar reformatted images perpendicular to the vessel long-axis. The vessel cross-sectional area stenosis (MLA/CSA ratio) was calculated. DSCT results were compared with IVUS and QCA. A good correlation between DSCT and IVUS was noted for diameter and area stenosis (r=0.69 and r=0.73), with an overestimation of MLD stenosis by DSCT (+9.1%) and an underestimation of MLA stenosis (-5.8%). For MLD and MLA, high correlation coefficients (r=0.78 and r=0.90, respectively) were found between DSCT and IVUS; and the bias was almost zero (-0.41 mm and +0.1mm(2), respectively). The correlation between DSCT and QCA was moderate (r=0.60) for MLD stenosis with minor overestimation by DSCT (+4.0%) and moderate (r=0.59) for MLD (bias, +0.01 mm). The cross-sectional area stenosis showed a moderate correlation (r=0.59) between DSCT and IVUS (+0.00). DSCT allows accurate quantification of coronary stenosis as compared to IVUS. An excellent correlation was found for the MLA between DSCT and IVUS.

• Cardiac CT angiography for the diagnosis of mitral valve prolapse: comparison with echocardiography1.

  Authors: Gudrun M Feuchtner, Hatem Alkadhi, Christoph Karlo, Ammar Sarwar, Andreas Meier, Wolfgang Dichtl, Sebastian Leschka, Ron Blankstein, Juerg Gruenenfelder, Paul Stolzmann, Ricardo C Cury

  Radiology. 02/2010; 254(2):374-83.

  To evaluate the diagnostic performance of coronary computed tomographic (CT) angiography for the diagnosis of mitral valve prolapse (MVP). The retrospective case-controlled multicenter study protocolTo evaluate the diagnostic performance of coronary computed tomographic (CT) angiography for the diagnosis of mitral valve prolapse (MVP). The retrospective case-controlled multicenter study protocol was approved by the institutional review boards. The U.S. part of the study was HIPAA compliant. One hundred twelve patients who underwent electrocardiographically gated 64-section coronary CT angiography (n = 60) or dual-source coronary CT angiography (n = 52) and transthoracic echocardiography (TTE) were included. Fifty-three patients with MVP were matched for age and sex with 59 patients without MVP. CT images were analyzed on three-, two-, and four-chamber (CH) views by two independent observers. MVP was defined as a greater than 2-mm displacement of leaflets below the annulus plane and was subclassified as "billowing" (bowing) or "flail leaflet" (free leaflet margin displacement). Leaflet thickness was measured and defined as thickened if it was greater than 2 mm. The diagnostic performance of CT when three- and two-CH views were combined for the diagnosis of MVP was as follows: sensitivity, 96%; specificity, 93%; positive predictive value (PPV), 93%; and negative predictive value, 96%. On four-CH views, the excursion of billowing was higher than it was on three-CH views (P <.001), and the PPV of the four-CH view for diagnosis of MVP was 89%. The correlation between CT and TTE for excursion of billowing was high (r = 0.80-0.91). In a subset of 32 patients, the agreement between CT and TTE for differentiation of billowing (n = 13) and flail leaflet (n = 2) was 100%. Leaflet thickening was more prevalent in patients with MVP than it was in those without (71% vs 20%, P <.001), and correlation with TTE was good (r = 0.81 [anterior leaflet] and 0.77 [posterior leaflet]). Conclusion: The combined use of three- and two-CH views allows an accurate diagnosis of MVP at coronary CT angiography.

• Tuberculous pseudoaneurysms of the thoracic aorta: comprehensive evaluation by cardiovascular magnetic resonance.

  Authors: Ricardo Loureiro, Hiram G Bezerra, Ammar Sarwar, Rodrigo Pale, Stuart Houser, Ricardo C Cury

  Circulation. 12/2009; 120(24):e285-7.

• Direct comparison of rest and adenosine stress myocardial perfusion CT with rest and stress SPECT.

  Authors: David Okada, Brian Ghoshhajra, Ron Blankstein, Jose Rocha-Filho, Leonid Shturman, Ian Rogers, Hiram Bezerra, Ammar Sarwar, Henry Gewirtz, Udo Hoffmann, Wilfred Mamuya, Thomas Brady, Ricardo Cury

  Journal of nuclear cardiology : official publication of the American Society of Nuclear Cardiology. 11/2009;

  INTRODUCTION: We have recently described a technique for assessing myocardial perfusion using adenosine-mediated stress imaging (CTP) with dual source computed tomography. SPECT myocardial perfusionINTRODUCTION: We have recently described a technique for assessing myocardial perfusion using adenosine-mediated stress imaging (CTP) with dual source computed tomography. SPECT myocardial perfusion imaging (SPECT-MPI) is a widely utilized and extensively validated method for assessing myocardial perfusion. The aim of this study was to determine the level of agreement between CTP and SPECT-MPI at rest and under stress on a per-segment, per-vessel, and per-patient basis. METHODS: Forty-seven consecutive patients underwent CTP and SPECT-MPI. Perfusion images were interpreted using the 17 segment AHA model and were scored on a 0 (normal) to 3 (abnormal) scale. Summed rest and stress scores were calculated for each vascular territory and patient by adding corresponding segmental scores. RESULTS: On a per-segment basis (n = 799), CTP and SPECT-MPI demonstrated excellent correlation: Goodman-Kruskall gamma = .59 (P < .0001) for stress and .75 (P < .0001) for rest. On a per-vessel basis (n = 141), CTP and SPECT-MPI summed scores demonstrated good correlation: Pearson r = .56 (P < .0001) for stress and .66 (P < .0001) for rest. On a per-patient basis (n = 47), CTP and SPECT-MPI demonstrated good correlation: Pearson r = .60 (P < .0001) for stress and .76 (P < .0001) for rest. CONCLUSIONS: CTP compares favorably with SPECT-MPI for detection, extent, and severity of myocardial perfusion defects at rest and stress.

• Adenosine-induced stress myocardial perfusion imaging using dual-source cardiac computed tomography.

  Authors: Ron Blankstein, Leon D Shturman, Ian S Rogers, Jose A Rocha-Filho, David R Okada, Ammar Sarwar, Anand V Soni, Hiram Bezerra, Brian B Ghoshhajra, Milena Petranovic, Ricardo Loureiro, Gudrun Feuchtner, Henry Gewirtz, Udo Hoffmann, Wilfred S Mamuya, Thomas J Brady, Ricardo C Cury

  Journal of the American College of Cardiology. 09/2009; 54(12):1072-84.

  OBJECTIVES: This study sought to determine the feasibility of performing a comprehensive cardiac computed tomographic (CT) examination incorporating stress and rest myocardial perfusion imagingOBJECTIVES: This study sought to determine the feasibility of performing a comprehensive cardiac computed tomographic (CT) examination incorporating stress and rest myocardial perfusion imaging together with coronary computed tomography angiography (CTA). BACKGROUND: Although cardiac CT can identify coronary stenosis, very little data exist on the ability to detect stress-induced myocardial perfusion defects in humans. METHODS: Thirty-four patients who had a nuclear stress test and invasive angiography were included in the study. Dual-source computed tomography (DSCT) was performed as follows: 1) stress CT: contrast-enhanced scan during adenosine infusion; 2) rest CT: contrast-enhanced scan using prospective triggering; and 3) delayed scan: acquired 7 min after rest CT. Images for CTA, computed tomography perfusion (CTP), and single-photon emission computed tomography (SPECT) were each read by 2 independent blinded readers. RESULTS: The DSCT protocol was successfully completed for 33 of 34 subjects (average age 61.4 +/- 10.7 years; 82% male; body mass index 30.4 +/- 5 kg/m(2)) with an average radiation dose of 12.7 mSv. On a per-vessel basis, CTP alone had a sensitivity of 79% and a specificity of 80% for the detection of stenosis > or =50%, whereas SPECT myocardial perfusion imaging had a sensitivity of 67% and a specificity of 83%. For the detection of vessels with > or =50% stenosis with a corresponding SPECT perfusion abnormality, CTP had a sensitivity of 93% and a specificity of 74%. The CTA during adenosine infusion had a per-vessel sensitivity of 96%, specificity of 73%, and negative predictive value of 98% for the detection of stenosis > or =70%. CONCLUSIONS: Adenosine stress CT can identify stress-induced myocardial perfusion defects with diagnostic accuracy comparable to SPECT, with similar radiation dose and with the advantage of providing information on coronary stenosis.

• Diagnostic and prognostic value of absence of coronary artery calcification.

  Authors: Ammar Sarwar, Leslee J Shaw, Michael D Shapiro, Ron Blankstein, Udo Hoffman, Ricardo C Cury, Suhny Abbara, Thomas J Brady, Matthew J Budoff, Roger S Blumenthal, Khurram Nasir

  JACC. Cardiovascular imaging. 07/2009; 2(6):675-88.

  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: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.

• Contrast-enhanced cine cardiac MR detects impairment of coronary microvascular perfusion in patients after acute myocardial infarct

  Authors: Ricardo Loureiro, Hiram Bezerra, Joalbo Andrade, Chun-Ho Yun, Ammar Sarwar, Michael Bolen, Thomas Brady, Ricardo Cury

  Journal of Cardiovascular Magnetic Resonance. 01/2009;

• Myocardial salvage by contrast-enhanced cine MR imaging: validation study against conventional T2 edema imaging and angiographic estimates of myocardium at risk during acute myocardial infarction

  Authors: Ricardo Loureiro, Hiram Bezerra, Joalbo Andrade, Chun-Ho Yun, Ammar Sarwar, Michael Bolen, Ricardo Cury

  Journal of Cardiovascular Magnetic Resonance. 01/2009;

• Distal radius in adolescent girls with anorexia nervosa: trabecular structure analysis with high-resolution flat-panel volume CT.

  Authors: Miriam A Bredella, Madhusmita Misra, Karen K Miller, Ijad Madisch, Ammar Sarwar, Arnold Cheung, Anne Klibanski, Rajiv Gupta

  Radiology. 12/2008; 249(3):938-46.

  PURPOSE: To examine trabecular microarchitecture with high-resolution flat-panel volume computed tomography (CT) and bone mineral density (BMD) with dual-energy x-ray absorptiometry (DXA) inPURPOSE: To examine trabecular microarchitecture with high-resolution flat-panel volume computed tomography (CT) and bone mineral density (BMD) with dual-energy x-ray absorptiometry (DXA) in adolescent girls with anorexia nervosa (AN) and to compare these results with those in normal-weight control subjects. MATERIALS AND METHODS: The study was approved by the institutional review board and complied with HIPAA guidelines. Informed consent was obtained. Twenty adolescent girls, 10 with mild AN (mean age, 15.9 years; range, 13-18 years) and 10 age- and sex-matched normal-weight control subjects (mean age, 15.9 years; range, 12-18 years) underwent flat-panel volume CT of distal radius to determine apparent trabecular bone volume fraction (BV/TV), apparent trabecular number (TbN), apparent trabecular thickness (TbTh), and apparent trabecular separation (TbSp). All subjects underwent DXA of spine, hip, and whole body to determine BMD and body composition. The means and standard deviations (SDs) of structure parameters were calculated for AN and control groups. Groups were compared (Student t test). Linear regression analysis was performed. RESULTS: AN subjects compared with control subjects, respectively, showed significantly lower mean values for BV/TV (0.37% +/- 0.05 [SD] vs 0.46% +/- 0.03, P = .0002) and TbTh (0.31 mm +/- 0.03 vs 0.39 mm +/- 0.03, P < .0001) and higher mean values for TbSp (0.54 mm +/- 0.13 vs 0.44 mm +/- 0.04, P = .02). TbN was lower in AN subjects than in control subjects, but the difference was not significant (1.17 mm(-3) +/- 0.15 vs 1.22 mm(-3) +/- 0.07, P = .43). There was no significant difference in BMD between AN and control subjects. BMD parameters showed positive correlation with BV/TV and TbTh in the control group (r = 0.55-0.84, P = .05-.01) but not in AN patients. CONCLUSION: Flat-panel volume CT is effective in evaluation of trabecular structure in adolescent girls with AN and demonstrates that bone structure is abnormal in these patients compared with that in normal-weight control subjects despite normal BMD. SUPPLEMENTAL MATERIAL: http://radiology.rsnajnls.org/cgi/content/full/249/3/938/DC1.

• Quantitative Analysis of Intraventricular Dyssynchrony Using Wall Thickness by Multidetector Computed Tomography.

  Authors: Quynh A Truong, Jagmeet P Singh, Christopher P Cannon, Ammar Sarwar, Khurram Nasir, Angelo Auricchio, Francesco F Faletra, Antonio Sorgente, Cristina Conca, Tiziano Moccetti, Mark Handschumacher, Thomas J Brady, Udo Hoffmann

  JACC. Cardiovascular imaging. 11/2008; 1(6):772-781.

  OBJECTIVES: We sought to determine the feasibility of cardiac computed tomography (CT) to detect significant differences in the extent of left ventricular dyssynchrony in heart failure (HF) patientsOBJECTIVES: We sought to determine the feasibility of cardiac computed tomography (CT) to detect significant differences in the extent of left ventricular dyssynchrony in heart failure (HF) patients with wide QRS, HF patients with narrow QRS, and age-matched controls. BACKGROUND: The degree of mechanical dyssynchrony has been suggested as a predictor of response to cardiac resynchronization therapy. There have been no published reports of dyssynchrony assessment with the use of CT. METHODS: Thirty-eight subjects underwent electrocardiogram-gated contrast-enhanced 64-slice multidetector CT. The left ventricular endocardial and epicardial boundaries were delineated from short-axis images reconstructed at 10% phase increments of the cardiac cycle. Global and segmental CT dyssynchrony metrics that used changes in wall thickness, wall motion, and volume over time were assessed for reproducibility. We defined a global metric using changes in wall thickness as the dyssynchrony index (DI). RESULTS: The DI was the most reproducible metric (interobserver and intraobserver intraclass correlation coefficients >/=0.94, p < 0.0001) and was used to determine differences between the 3 groups: HF-wide QRS group (ejection fraction [EF] 22 +/- 8%, QRS 163 +/- 28 ms), HF-narrow QRS (EF 26 +/- 7%, QRS 96 +/- 11 ms), and age-matched control subjects (EF 64 +/- 5%, QRS 87 +/- 9 ms). Mean DI was significantly different between the 3 groups (HF-wide QRS: 152 +/- 44 ms, HF-narrow QRS: 121 +/- 58 ms, and control subjects: 65 +/- 12 ms; p < 0.0001) and greater in the HF-wide QRS (p < 0.0001) and HF-narrow QRS (p = 0.005) groups compared with control subjects. We found that DI had a good correlation with 2-dimensional (r = 0.65, p = 0.012) and 3-dimensional (r = 0.68, p = 0.008) echocardiographic dyssynchrony. CONCLUSIONS: Quantitative assessment of global CT-derived DI, based on changes in wall thickness over time, is highly reproducible and renders significant differences between subjects most likely to have dyssynchrony and age-matched control subjects.

• Calcified Plaque: Measurement of Area at Thin-Section Flat-Panel CT and 64-Section Multidetector CT and Comparison with Histopathologic Findings.

  Authors: Ammar Sarwar, Johannes Rieber, Eline A Q Mooyaart, Sujith K Seneviratne, Stuart L Houser, Fabian Bamberg, O Christopher Raffel, Rajiv Gupta, Mannudeep K Kalra, Homer Pien, Hang Lee, Thomas J Brady, Udo Hoffmann

  Radiology. 09/2008;

  The purpose of this study was to assess the blooming artifacts in ex vivo coronary arteries at multidetector computed tomography (CT) and flat-panel-volume CT by comparing measured areas of calcifiedThe purpose of this study was to assess the blooming artifacts in ex vivo coronary arteries at multidetector computed tomography (CT) and flat-panel-volume CT by comparing measured areas of calcified plaque with respect to the reference standard of histopathologic findings. Three ex vivo hearts were scanned with multidetector CT and flat-panel-volume CT after institutional review board approval. The area of calcified plaque was measured at histopathologic examination, multidetector CT, and flat-panel-volume CT. The plaque area was overestimated at multidetector CT by 400% (4.61/1.15) on average, and the predicted difference between the measurements was significant (3.46 mm(2), P = .018). The average overestimation of plaque area at flat-panel-volume CT was twofold (214% [2.18/1.02]), and the predicted difference was smaller (1.16 mm(2), P = .08). The extent of the blooming artifact in visualizing calcified coronary plaque is reduced by using flat-panel-volume CT. (c) RSNA, 2008.

• Cardiac magnetic resonance imaging for the evaluation of ventricular function.

  Authors: Ammar Sarwar, Michael D Shapiro, Suhny Abbara, Ricardo C Cury

  Seminars in roentgenology. 08/2008; 43(3):183-92.

• Musculoskeletal applications of flat-panel volume CT.

  Authors: Benjamin Reichardt, Ammar Sarwar, Soenke Bartling, Arnold Cheung, Michael Grasruck, Christianne Leidecker, Miriam Bredella, Thomas Brady, Rajiv Gupta

  Skeletal radiology. 05/2008;

  Flat-panel volume computed tomography (fpVCT) is a recent development in imaging. We discuss some of the musculoskeletal applications of a high-resolution flat-panel CT scanner. FpVCT has four mainFlat-panel volume computed tomography (fpVCT) is a recent development in imaging. We discuss some of the musculoskeletal applications of a high-resolution flat-panel CT scanner. FpVCT has four main advantages over conventional multidetector computed tomography (MDCT): high-resolution imaging; volumetric coverage; dynamic imaging; omni-scanning. The overall effective dose of fpVCT is comparable to that of MDCT scanning. Although current fpVCT technology has higher spatial resolution, its contrast resolution is slightly lower than that of MDCT (5-10HU vs. 1-3HU respectively). We discuss the efficacy and potential utility of fpVCT in various applications related to musculoskeletal radiology and review some novel applications for pediatric bones, soft tissues, tumor perfusion, and imaging of tissue-engineered bone growth. We further discuss high-resolution CT and omni-scanning (combines fluoroscopic and tomographic imaging).

• Anomalous left inferior pulmonary vein crossing midline and draining via common ostium with right inferior pulmonary vein.

  Authors: Ammar Sarwar, Khurram Nasir, Michael D Shapiro, Suhny Abbara

  Journal of cardiovascular electrophysiology. 03/2008; 19(2):223.

• Hepatic steatosis is associated with a greater prevalence of coronary artery calcification in asymptomatic men.

  Authors: Raul D Santos, Khurram Nasir, Raquel D Conceição, Ammar Sarwar, Jose A M Carvalho, Roger S Blumenthal

  Atherosclerosis. 11/2007; 194(2):517-9.

• Combined effect of high low-density lipoprotein cholesterol and metabolic syndrome on subclinical coronary atherosclerosis in white men without clinical evidence of myocardial ischemia.

  Authors: Catherine Y Campbell, Khurram Nasir, Ammar Sarwar, Romeu S Meneghelo, Jose A M Carvalho, Roger S Blumenthal, Raul D Santos

  The American journal of cardiology. 09/2007; 100(5):840-3.

  High low-density lipoprotein (LDL) cholesterol and the presence of metabolic syndrome (MS) are established risk factors for clinical and subclinical cardiovascular disease (CVD). However, theHigh low-density lipoprotein (LDL) cholesterol and the presence of metabolic syndrome (MS) are established risk factors for clinical and subclinical cardiovascular disease (CVD). However, the relative contribution to CVD risk of MS and high LDL cholesterol is not well defined. Therefore, the aim was assess the relative risk for the presence of coronary artery calcification (CAC) with metabolic syndrome (MS) compared with that of moderate or high LDL cholesterol. A total of 440 consecutive asymptomatic men (mean age 46 +/- 7 years, range 29 to 65) presenting for CVD risk stratification were studied. MS was defined using National Cholesterol Education Program Adult Treatment Panel III criteria (n = 112; 24%). Moderate LDL cholesterol was defined as 130 to 159 mg/dl, and high LDL cholesterol as >/=160 mg/dl (n = 76; 17%). Overall, CAC was observed in 190 men (40%). The prevalence of CAC >0 was lowest in MS-negative men with LDL cholesterol <130 (35%) or 130 to 159 mg/dl (34%) and highest in MS-positive men with LDL cholesterol >/=160 mg/dl (80%). MS-positive men with LDL cholesterol of 130 to 159 mg/dl had CAC prevalence similar to that of MS-negative men with LDL cholesterol >/=160 mg/dl (54% vs 57%, respectively). This relation persisted with additional adjustment for age, smoking status, and cholesterol-lowering medication. In logistic regression analyses, the odds ratio for CAC >0 was highest in MS-positive men combined with high LDL cholesterol. In conclusion, these results suggest that the risk of CAC in asymptomatic men with moderate or high LDL cholesterol is magnified in persons with MS.

• Utility of cardiovascular magnetic resonance to predict left ventricular recovery after primary percutaneous coronary intervention for patients presenting with acute ST-segment elevation myocardial infarction.

  Authors: Michael D Shapiro, Koen Nieman, Khurram Nasir, Cesar H Nomura, Ammar Sarwar, Maros Ferencik, Suhny Abbara, Udo Hoffman, Herman K Gold, Ik-Kyung Jang, Thomas J Brady, Ricardo C Cury

  The American journal of cardiology. 08/2007; 100(2):211-6.

  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 toCardiac 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.

• Gender differences in coronary arteries and thoracic aorta calcification.

  Authors: Khurram Nasir, Ariel Roguin, Ammar Sarwar, John A Rumberger, Roger S Blumenthal

  Arteriosclerosis, thrombosis, and vascular biology. 06/2007; 27(5):1220-2.

• Measuring subclinical atherosclerosis: is homocysteine relevant?

  Authors: Ahmad B Sarwar, Ammar Sarwar, Boaz D Rosen, Khurram Nasir

  Clinical chemistry and laboratory medicine : CCLM / FESCC. 02/2007; 45(12):1667-77.

  OBJECTIVES: We systematically reviewed published studies looking at the relationship between total serum homocysteine (tHcy) and subclinical markers of atherosclerosis, such as carotid intimal-medialOBJECTIVES: We systematically reviewed published studies looking at the relationship between total serum homocysteine (tHcy) and subclinical markers of atherosclerosis, such as carotid intimal-medial thickness (C-IMT), coronary artery calcium (CAC) and ankle-brachial index (ABI) in asymptomatic individuals. We analyzed these studies to examine this relationship as well as to guide future avenues of investigation by identifying studies that will help in the inclusion of tHcy levels in current guidelines on atherosclerotic disease management. BACKGROUND: tHcy has been known to be associated with clinically evident atherosclerotic disease. However, tHcy is not incorporated in current guidelines for diagnosis of subclinical disease in high-risk asymptomatic individuals. METHODS: We searched online databases (e.g., PUBMED, MEDLINE) for published articles assessing the relationship between tHcy and C-IMT, CAC and ABI. We limited the studies to asymptomatic populations, and excluded any study including symptomatic patients or individuals with a history of coronary, peripheral or cerebrovascular disease. RESULTS: A systemic review of 19 articles revealed a significant association between elevated levels of tHcy and subclinical markers of atherosclerosis in asymptomatic individuals in most studies. Mean tHcy levels were consistently found to be higher in men compared to women. A total of 12 studies showed a significant association between tHcy and other risk markers of atherosclerosis, even after adjusting for age, sex and conventional risk factors. There were seven studies in unique populations that showed no significant relationship. We also observed that studies lowering baseline tHcy levels did not lead to an improvement in C-IMT, CAC or ABI scores. This might indicate that tHcy has a stronger role as a marker of atherosclerotic disease than as a risk factor for the same. CONCLUSIONS: Based on our review, we conclude that there is a significant association between the subclinical atherosclerotic process and tHcy, and it shows potential as a cheap marker for risk stratification of asymptomatic patients. However, future studies further elucidating this association and elaborating the exact role of tHcy in the atherosclerotic disease process are required. The results of these studies suggest the incorporation of plasma tHcy levels in future risk reduction protocols for identification of individuals at higher risk of atherosclerotic events, and thus to categorize them for more aggressive treatment with established preventive and therapeutic measures.