Publications by authors named "Ahmed Aljizeeri"

26 Publications

  • Page 1 of 1

The prognostic role of cardiac positron emission tomography imaging in patients with sarcoidosis: A systematic review.

J Nucl Cardiol 2021 Aug 6;28(4):1545-1552. Epub 2021 Jul 6.

Houston Methodist Debakey Heart & Vascular Center, 6550 Fannin Street, Smith Tower - Suite 1801, Houston, TX, 77030, USA.

Purpose: Sarcoidosis is a multi-systemic inflammatory disease of unknown etiology. Cardiac sarcoidosis (CS) has been reported in as much as 25% of patients with systemic involvement. Fluorodeoxyglucose (FDG) positron emission tomography (PET) has a high diagnostic sensitivity/specificity in the diagnosis of CS. The aim of this review is to summarize evidence on the prognostic role of FDG PET.

Methods: Studies were identified by searching MEDLINE from inception to October 2020. Medical subject headings (MeSH) terms for sarcoidosis; cardiac and FDG PET imaging were used. Studies of any design assessing the prognostic role of FDG PET in patients with either suspected or confirmed cardiac sarcoidosis imaging done at baseline were included. Abnormal PET was defined as abnormal metabolism (presence of focal or focal-on-diffuse uptake of FDG) OR abnormal metabolism and a perfusion defect. Studies reporting any outcome measure were included. Pooled risk ratio for the composite outcome of MACE was done.

Results: A total of 6 studies were selected for final inclusion (515 patients, 53.4% women, 19.8% racial minorities.) Studies were institution based, retrospective in design and enrolled consecutive patients. All were observational in nature and published in English. All studies used a qualitative assessment of PET scans (abnormal FDG uptake with or without abnormal perfusion). Two studies assessed quantitative metrics (summed stress score in segments with abnormal FDG uptake, standardized uptake value and cardiac metabolic activity.) All studies reported major adverse cardiovascular events (MACE) as a composite outcome. After a mean follow up ranging from 1.4 to 4.1 years, there were a total of 105 MACE. All studies included death (either all-cause death or sudden cardiac death) and ventricular arrhythmia (ventricular tachycardia or ventricular fibrillation) as a component of MACE. Four of the six studies adjusted for several characteristics in their analysis. All four studies used left ventricular ejection fraction (LVEF). However, other adjustment variables were not consistent across studies. Five studies found a positive prognostic association with the primary outcome, two of which assessing right ventricular uptake.

Conclusion: Although available evidence indicates FDG PET can be used in the risk stratification of patients with CS, our findings show further studies are needed to quantify the effect in this patient group.
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http://dx.doi.org/10.1007/s12350-021-02681-zDOI Listing
August 2021

Myocardial Flow Reserve and Coronary Calcification in Prognosis of Patients With Suspected Coronary Artery Disease.

JACC Cardiovasc Imaging 2021 Mar 11. Epub 2021 Mar 11.

Houston Methodist DeBakey Heart & Vascular Center, Houston Methodist Hospital, Houston, Texas, USA. Electronic address:

Objectives: The aim of this analysis is to examine the incremental prognostic value of coronary artery calcium (CAC) score and myocardial flow reserve (MFR) in patients with suspected coronary artery disease (CAD) undergoing positron emission tomography (PET) myocardial perfusion imaging (MPI).

Background: Advances in cardiac PET and computed tomography imaging enabled the simultaneous acquisition of anatomic and physiological data for patients suspected of CAD.

Methods: Consecutive patients who underwent PET MPI and CAC score calculation at King Abdulaziz Cardiac Center, Riyadh, Saudi Arabia, between May 2011 and May 2018 were included in the study. MPI and CAC images were obtained in the same setting. The primary endpoint of the study was a composite of cardiac death and nonfatal myocardial infarction. Cox proportional hazard regression was used to assess the incremental prognostic value of CAC and MFR by sequentially adding the variables to a model that included clinical and PET variables.

Results: A total of 4,008 patients (mean age 59.7 ± 11.6 years, 55% women) were included in the analysis. Risk factors were prevalent (77.6% hypertension, 58.1% diabetes). In total, 35.9% of the cohort had CAC of 0, 16.5% had CAC ≥400, and 43.9% had MFR <2. Over a median follow up of 1.9 years, 130 (3.2%) patients had cardiac death/nonfatal myocardial infarction. CAC and MFR score added incremental prognostic value over clinical and perfusion variables (base model: c-index 0.8137; Akaike information criterion [AIC]: 1,865.877; p = 0.0011; CAC model: c-index = 0.8330; AIC: 1,850.810; p = 0.045 vs. base model; MFR model: c-index = 0.8279; AIC: 1,859.235; p = 0.024). Combining CAC and MFR did not enhance risk prediction (c-index = 0.8435; AIC: 1,846.334; p = 0.074 vs. MFR model; p = 0.21 vs. CAC model.) CONCLUSIONS: In this large cohort of patients referred for PET MPI, both CAC and MFR independently added incremental prognostic value over clinical and MPI variables. Although combining both may have synergetic prognostic effect, this relation was not shown in multivariable model of this analysis.
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http://dx.doi.org/10.1016/j.jcmg.2021.01.024DOI Listing
March 2021

Left ventricular mass on positron emission tomography: Validation against cardiovascular magnetic resonance.

J Nucl Cardiol 2021 Feb 24. Epub 2021 Feb 24.

Houston Methodist Debakey Heart & Vascular Center, Houston Methodist Hospital, Houston, TX, USA.

Background: Left ventricular hypertrophy (LVH) is an important clinical finding that is independently associated with mortality and cardiovascular events. We aimed to assess the interstudy variability of LV mass quantitation between PET and CMR.

Methods: Patients who underwent both PET and CMR within 1 year were identified from prospective institutional registries. LV mass on PET was compared against LV mass on CMR using several statistical measures of agreement.

Results: A total of 105 patients (mean age 60 ± 14 years, 67.6% male) were included. The median (interquartile range, IQR) duration between CMR and PET was 47 (11-154) days. The median (IQR) LV mass values were 168.0 g (126.0-202.0) on CMR and 174.0 g (150.0-212.0) with PET (absolute mean difference 29.42 ± 25.3). There was a good correlation (Spearman ρ = 0.81, P < 0.001; Intraclass Correlation Coefficient 0.78, 95% CI 0.70-0.85, P < 0.001) with moderate limits of agreement (95% limits of agreement - 63.78 to 83.7.) Results were consistent, albeit with moderate correlation, in subgroups of patients with LVH, in patients with myocardial infarction, in patients with LV ejection fraction < 50%, and those with limited image quality. LV mass on PET tended to be underestimated at high values compared to CMR.

Conclusion: We demonstrate good correlation and reproducibility of LV mass quantitation by PET against the reference standard of CMR across a wide range of normal and diseased hearts with a tendency of PET to underestimate mass at higher mass values.
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http://dx.doi.org/10.1007/s12350-021-02537-6DOI Listing
February 2021

Non-invasive Cardiac Imaging During the Coronavirus Disease 2019 (COVID-19) Pandemic: A Statement from the Cardiac Imaging Working Group of the Saudi Heart Association.

J Saudi Heart Assoc 2020 18;32(5):6-10. Epub 2020 May 18.

King Abdulaziz Cardiac Center, Ministry of National Guard-Health Affairs, Riyadh, Saudi Arabia.

COVID-19 pandemic has led to major changes in the delivery of medical care around the globe. Many investigations and elective procedures had to be rescheduled to decrease the risk of spreading the infection. Non-invasive cardiac imaging studies are requested to guide appropriate cardiac care in a variety of urgent, semi-urgent, and elective procedures. This position statement of the Cardiac Imaging Working Group of the Saudi Heart Association provides guidance into the protection of healthcare personnel, assessment of the indications of the imaging studies, and highlights consideration before, during, and after the study.
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http://dx.doi.org/10.37616/2212-5043.1029DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7735958PMC
May 2020

Automation in Nuclear Cardiology: Time for Flurpiridaz to Join the Club.

J Nucl Cardiol 2020 Nov 17. Epub 2020 Nov 17.

Houston Methodist DeBakey Heart & Vascular Center, Houston Methodist Hospital, 6550 Fannin Street, Smith Tower - Suite 1801, Houston, TX, 77030, USA.

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http://dx.doi.org/10.1007/s12350-020-02421-9DOI Listing
November 2020

Coronary artery disease in patients with human immunodeficiency virus infection.

J Nucl Cardiol 2021 Apr 20;28(2):510-530. Epub 2020 Aug 20.

Department of Cardiology and Nuclear Cardiovascular Imaging Laboratory, New York Medical College, Westchester Medical Center, 100 Woods Road, Valhalla, NY, 10595, USA.

The life expectancy of people infected with human immunodeficiency virus (HIV) is rising due to better access to combination anti-retroviral therapy (ART). Although ART has reduced acquired immune deficiency syndrome (AIDS) related mortality and morbidity, there has been an increase in non-AIDS defining illnesses such as diabetes mellitus, hypercholesterolemia and coronary artery disease (CAD). HIV is a disease marked by inflammation which has been associated with specific biological vascular processes increasing the risk of premature atherosclerosis. The combination of pre-existing risk factors, atherosclerosis, ART, opportunistic infections and coagulopathy contributes to rising CAD incidence. The prevalence of CAD has emerged as a major contributor of morbidity in these patients due to longer life expectancy. However, ART has been associated with lipodystrophy, dyslipidemia, insulin resistance, diabetes mellitus and CAD. These adverse effects, along with drug-drug interactions when ART is combined with cardiovascular drugs, result in significant challenges in the care of this group of patients. Exercise tolerance testing, echocardiography, myocardial perfusion imaging, coronary computed tomography angiography and magnetic resonance imaging help in the diagnosis of CAD and heart failure and help predict cardiovascular outcomes in a manner similar to non-infected individuals. This review will highlight the pathogenesis and factors that link HIV to CAD, presentation and treatment of HIV-patients presenting with CAD and review briefly the cardiac imaging modalities used to identify this entity and help prognosticate future outcomes.
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http://dx.doi.org/10.1007/s12350-020-02280-4DOI Listing
April 2021

Myocardial Perfusion Imaging Using Positron Emission Tomography.

Methodist Debakey Cardiovasc J 2020 Apr-Jun;16(2):114-121

HOUSTON METHODIST DEBAKEY HEART & VASCULAR CENTER, HOUSTON METHODIST HOSPITAL, HOUSTON, TEXAS.

Coronary artery disease (CAD), also known as ischemic heart disease, is a major cause of morbidity and mortality worldwide, and timely noninvasive diagnosis of clinical and subclinical CAD is imperative to mitigate its burden on individual patients and populations. Positron emission tomography (PET) is a versatile tool that can perform relative myocardial perfusion imaging (MPI) with high accuracy; furthermore, it provides valuable information about the coronary microvasculature using rest and stress myocardial blood flow (MBF) and coronary flow reserve (CFR) measurements. Several radiotracers are approved by the US Food and Drug Administration to help with MPI, MBF, and CFR evaluation. A large body of evidence indicates that evaluation of the coronary microcirculation using MBF and CFR provides strong diagnostic and prognostic data in a multitude of patient populations. This review describes the technical aspects of PET compared to other modalities and discusses its clinical uses for diagnosis and prognosis of coronary arterial epicardial and microcirculatory disease.
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http://dx.doi.org/10.14797/mdcj-16-2-114DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7350808PMC
September 2020

Prevalence and predictors of frailty in a high-income developing country: A cross-sectional study.

Qatar Med J 2019 23;2019(3):20. Epub 2020 Jan 23.

Houston Methodist DeBakey Heart & Vascular Center, Houston, Texas, USA.

Frailty is a state of vulnerability and a decreased physiological response to stressors. As the population ages, the prevalence of frailty is expected to increase. Thus, identifying tools and resources that efficiently predict frailty among the Saudi population is important. We aimed to describe the prevalence and predictors of frailty among Saudi patients referred for cardiac stress testing with nuclear imaging. We included 876 patients (mean age 60.3 ± 11 years, women 48%) who underwent clinically indicated cardiac nuclear stress testing between January and October 2016. Fried Clinical Frailty Scale was used to assess frailty. Patients were considered frail if they had a score of four or higher. Multivariate adjusted logistic regression models were used to determine the independent predictors of elderly frail patients. In this cohort, the median age of the included patients was 61 years, and the prevalence of frailty was 40%. The frail patients were older, more frequently women, and had a higher body mass index. Additionally, frailty was associated with a higher prevalence of cardiovascular risk factors: hypertension (85% vs. 70%) and diabetes (75% vs. 60%). In a fully adjusted logistic regression model, women, hypertension, and obesity (BMI ≥ 30 kg/m) were independent predictors of elderly frail patients. With the aging of the Saudi population, frailty prevalence is expected to increase. Elderly, obesity, hypertension, and female gender are risk factors of frailty. Interventions to reduce frailty should be focused on this high-risk population.
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http://dx.doi.org/10.5339/qmj.2019.20DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6977005PMC
January 2020

The role of cardiac imaging in the management of non-ischemic cardiovascular diseases in human immunodeficiency virus infection.

J Nucl Cardiol 2020 06 12;27(3):801-818. Epub 2019 Mar 12.

Houston Methodist DeBakey Heart & Vascular Center, Houston Methodist Hospital, 6565 Fannin Street, Smith-19, Houston, TX, 77030, USA.

Infection with human immunodeficiency virus (HIV) has become the pandemic of the new century. About 36.9 million people are living with HIV worldwide. The introduction of antiretroviral therapy in 1996 has dramatically changed the global landscape of HIV care, resulting in significantly improved survival and changing HIV to a chronic disease. With near-normal life expectancy, contemporary cardiac care faces multiple challenges of cardiovascular diseases, disorders specific to HIV/AIDS, and those related to aging and higher prevalence of traditional risk factors. Non-ischemic cardiovascular diseases are major components of cardiovascular morbidity and mortality in HIV/AIDS. Non-invasive cardiac imaging plays a pivotal role in the management of these diseases. This review summarizes the non-ischemic presentation of the HIV cardiovascular spectrum focusing on the role of cardiac imaging in the management of these disorders.
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http://dx.doi.org/10.1007/s12350-019-01676-1DOI Listing
June 2020

Coronary artery calcium score to guide hypertension therapy!

Atherosclerosis 2019 03 25;282:162-164. Epub 2019 Jan 25.

Houston Methodist Debaky Heart and Vascular Center, Houston, TX, USA. Electronic address:

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http://dx.doi.org/10.1016/j.atherosclerosis.2019.01.014DOI Listing
March 2019

Utility of cardiac magnetic resonance in recurrent myocarditis.

J Saudi Heart Assoc 2017 Jul 22;29(3):214-218. Epub 2016 Oct 22.

Advanced Cardiac Imaging, King Abdulaziz Cardiac Center, Ministry of National Guard-Health Affairs, Riyadh, bSaudi Arabia.

We report a 26-year-old man who presented to the emergency department four times within a 4-year period with recurrent myocarditis. His presentations were characterized by chest pain, elevated troponin I, and normal coronary angiography. Endomyocardial biopsy showed nonspecific inflammatory process. Laboratory workup including viral screening and autoimmune markers were negative. Cardiac magnetic resonance imaging showed evidence of recurrent myocarditis with progressive appearance of new areas of myocardial delayed enhancement seen in each admission.
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http://dx.doi.org/10.1016/j.jsha.2016.08.002DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5475349PMC
July 2017

Assessment of myocardial blood flow and coronary flow reserve with positron emission tomography in ischemic heart disease: current state and future directions.

Heart Fail Rev 2017 07;22(4):441-453

Ministry of National Guard, Health Affairs, King Saud bin Abdulaziz University for Health Sciences, King Abdullah International Medical Research Center, King Abdulaziz Cardiac Center, Riyadh, Saudi Arabia.

Positron emission tomography (PET) is a versatile imaging technology that allows assessment of myocardial perfusion, both at a spatially relative scale and also in absolute terms, thereby enabling noninvasive evaluation of myocardial blood flow (MBF) and coronary flow reserve (CFR). Assessment of MBF using FDA-approved PET isotopes, such as Rb and N-ammonia, has been well validated, and several software packages are currently available, thereby allowing for MBF evaluation to be incorporated into routine workflow in contemporary nuclear laboratories. Incremental diagnostic and prognostic information provided with the knowledge of MBF has the potential for widespread applications. Improving the ability to identify the true burden of obstructive epicardial coronary stenoses and allowing for noninvasive assessment of coronary micro circulatory function can be achieved with MBF assessment. On the other hand, attenuated CFR has been shown to predict adverse cardiovascular prognosis in a variety of clinical settings and patient subgroups. With expanding applications of MBF, this tool promises to provide unique insight into the integrity of the entire coronary vascular bed beyond what is currently available with relative perfusion assessment. This review intends to provide an in-depth discussion of technical and clinical aspects of MBF assessment with PET as it relates to patients with ischemic heart disease.
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http://dx.doi.org/10.1007/s10741-017-9625-4DOI Listing
July 2017

Finding a gatekeeper to coronary angiography: a step in the right direction.

Eur Heart J Cardiovasc Imaging 2017 09;18(9):978-979

King Abdulaziz Cardiac Center, King Abdulaziz Medical City, Ministry of National Guard-Health PO Box 22490, Riyadh 11426, Riyadh, Saudi Arabia.

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http://dx.doi.org/10.1093/ehjci/jex100DOI Listing
September 2017

Postinfectious glomerulonephritis with a broken heart: A case report study.

Saudi J Kidney Dis Transpl 2017 May-Jun;28(3):615-620

Department of Medicine, King Abdulaziz Medical City, Riyadh, Saudi Arabia.

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http://dx.doi.org/10.4103/1319-2442.206470DOI Listing
July 2019

Cardiac magnetic resonance imaging in heart failure: where the alphabet begins!

Heart Fail Rev 2017 07;22(4):385-399

Divsions of Cardiology and Advanced Cardiac Imaging, King Abdulaziz Cardiac Center, King Abdulaziz Medical City (Riyadh), Ministry of National Guard - Health Affairs, P.O. Box 22490, Riyadh, 11426. Mail Code: 1413, Kingdom of Saudi Arabia.

Cardiac Magnetic Resonance Imaging has become a cornerstone in the evaluation of heart failure. It provides a comprehensive evaluation by answering all the pertinent clinical questions across the full pathological spectrum of heart failure. Nowadays, CMR is considered the gold standard in evaluation of ventricular volumes, wall motion and systolic function. Through its unique ability of tissue characterization, it provides incremental diagnostic and prognostic information and thus has emerged as a comprehensive imaging modality in heart failure. This review outlines the role of main conventional CMR sequences in the evaluation of heart failure and their impact in the management and prognosis.
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http://dx.doi.org/10.1007/s10741-017-9609-4DOI Listing
July 2017

Cardiac computed tomography in current cardiology guidelines.

J Cardiovasc Comput Tomogr 2015 Nov-Dec;9(6):514-23. Epub 2015 Sep 28.

Advanced Cardiac Imaging, King Abdulaziz Cardiac Center, Ministry of National Guard - Health Affairs, Riyadh, Saudi Arabia; King Saud bin Abdulaziz University for Health Sciences, Saudi Arabia.

Practice guidelines issued by professional societies significantly impact cardiology practice throughout the world. They increasingly incorporate cardiac CT imaging. This review systematically analyzes clinical practice guidelines issued by the American College of Cardiology Foundation (ACCF)/American Heart Association (AHA) and the European Society of Cardiology (ESC) as well as the multi-societal appropriateness criteria in their latest versions as of September 1st, 2015, in order to identify the extent to which they include recommendations to use cardiac CT in specific clinical situations.
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http://dx.doi.org/10.1016/j.jcct.2015.09.003DOI Listing
September 2016

Importance of Reference Muscle Selection in Quantitative Signal Intensity Analysis of T2-Weighted Images of Myocardial Edema Using a T2 Ratio Method.

Biomed Res Int 2015 21;2015:232649. Epub 2015 Jun 21.

CMR Centre, Montreal Heart Institute, University of Montreal, Montreal, QC, Canada H1T 1C8 ; Stephenson CMR Centre, Libin Cardiovascular Institute of Alberta, University of Calgary, Calgary, AB, Canada T2N 2T9.

Objectives: The purpose of our study was to identify the suitability of various skeletal muscles as reference regions for calculating the T2 SI ratio for a semiautomated quantification of the extent of myocardial edema with T2-weighted images.

Methods: Thirty-four patients with acute myocardial infarction (MI) were enrolled. The extent of myocardial edema was determined by T2 SI ratio map, using 4 different muscles as reference: major and minor pectoralis, serratus anterior, teres minor-infraspinatus, and subscapularis. The size of myocardial edema as visually quantified was used as the standard of truth. The control group consisted of 15 patients with chronic MI. Intra- and interobserver variability were assessed.

Results: Due to poor image quality four patients were excluded from the analysis. In acute MI patients, serratus anterior muscle showed the strongest correlation with the visual analysis (r = 0.799; P < 0.001) and low inter- and intraobserver variability, while the other muscles resulted in a significant interobserver variability. In contrast, the use of other muscles as a reference led to overestimating edema size.

Conclusions: In acute MI patients, serratus anterior resulted to be the most reliable and reproducible muscle for measuring the extent of myocardial edema.
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http://dx.doi.org/10.1155/2015/232649DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4491384PMC
April 2016

Erratum to: Assessment of left ventricular ejection fraction using low radiation dose computed tomography.

J Nucl Cardiol 2016 06;23(3):422

Division of Cardiology, University of Ottawa Heart Institute, 40 Ruskin Street, Ottawa, ON, K1Y 4W7, Canada.

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http://dx.doi.org/10.1007/s12350-015-0211-7DOI Listing
June 2016

Assessment of left ventricular ejection fraction using low radiation dose computed tomography.

J Nucl Cardiol 2016 06 22;23(3):414-21. Epub 2015 May 22.

Division of Cardiology, University of Ottawa Heart Institute, 40 Ruskin Street, Ottawa, ON, K1Y 4W7, Canada.

Background: Cardiac CT is a non-invasive modality with the ability to estimate LVEF. However, given its limited temporal resolution and radiation, there has been initial resistance to use CT to measure LVEF. Developing an accurate, fast, low radiation dose protocol is desirable.

Objective: The objective of this study is to demonstrate that a 'low radiation dose' 64 slice cardiac computed tomography (CT) protocol is feasible and can accurately measure left ventricular ejection fraction (LVEF) while delivering a radiation dose lower than radionuclide angiography (RNA).

Methods: Patients undergoing RNA were prospectively screened and enrolled to undergo a 'low-dose' 64 slice CT LVEF protocol. LVEF measures, duration of each study and radiation dose between CT and RNA were compared.

Results: A total of 77 patients (mean age = 61.8 ± 12.2 years and 58 men) were analyzed. The mean LVEF measured by CT and RNA were 41.9 ± 15.2% and 39.4 ± 13.9%, respectively, (P = 0.154) with a good correlation (r = 0.863). Bland-Altman plot revealed a good agreement between the CT and RNA LVEF (mean difference of -2.4). There was good agreement between CT LVEF and RNA for identifying patients with LVEF ≤30% (kappa = 0.693) and LVEF ≥50% (kappa = 0.749). The mean dose estimated effective dose for CT and RNA were 4.7 ± 1.6 and 9.5 ± 1.0 mSv, respectively. The mean CT LVEF imaging duration (4:32 ± 3:05 minutes) was significantly shorter than the RNA image acquisition time (9:05 ± 2:36 minutes; p < 0.001).

Conclusion: The results of our study suggest that low-dose CT LVEF protocol is feasible, accurate, and fast while delivering a lower radiation dose than traditional RNA.
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http://dx.doi.org/10.1007/s12350-015-0123-6DOI Listing
June 2016

Obesity and coronary artery calcification: Can it explain the obesity-paradox?

Int J Cardiovasc Imaging 2015 Jun 19;31(5):1063-70. Epub 2015 Mar 19.

Department of Medicine, University of Ottawa, Ottawa, Canada.

The inverse relationship between obesity and adverse cardiovascular outcomes has been coined the 'obesity-paradox'. We sought to determine the relationship between measures of obesity [body mass index (BMI), body surface area (BSA) and body fat percentage (BF%)] and coronary artery calcification (CAC). We retrospectively analyzed patients who underwent CAC using the Agatston score. Baseline demographics were collected and BMI, BSA and BF% were calculated. A two-stage regression modeling approach was used to evaluate the association between BMI, BSA, BF% and Agatston score. Of the 6661 patients [mean age = 57.1 ± 10.8 years, men = 54.3%, median Agatston score = 14 (0, 163)], 0.1% were underweight, 21.3% had normal BMI, 39.1% were overweight and 39.4% were obese. The mean BMI, BSA and BF% were 29.6 ± 6.1 kg/m(2), 1.97 ± 0.25 m(2) and 37 ± 10 %, respectively. There was an independent association between the presence of CAC and BMI (5 kg/m(2) increments) (OR 1.05, CI 1.00-1.11, P = 0.038) and BF% (OR 2.38, CI 1.05-5.41, P = 0.038). Neither BMI categories nor large BSA independently predicted the presence of CAC. BF% predicted the extent of CAC in men but not in women, and higher BF% was associated with higher category of CAC severity in men only. BMI and BF% were independent predictors of the presence of CAC. BF% was associated with the extent of CAC and higher BF% was associated with higher category of CAC severity in men only. These results suggest that further study is needed to better understand the obesity-paradox.
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http://dx.doi.org/10.1007/s10554-015-0643-9DOI Listing
June 2015

Unroofed coronary sinus atrial septal defect: diagnosis by multimodality cardiac imaging.

Echocardiography 2014 Aug 25;31(7):E228-9. Epub 2014 Mar 25.

Division of Cardiology, University of Ottawa Heart Institute, Ottawa, Ontario, Canada.

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http://dx.doi.org/10.1111/echo.12588DOI Listing
August 2014

Integrating anatomical and functional imaging for the assessment of coronary artery disease.

Expert Rev Cardiovasc Ther 2013 Oct;11(10):1301-10

Department of Medicine (Cardiology), University of British Columbia, Canada.

Coronary artery disease (CAD) is a leading cause of morbidity and mortality. Invasive cardiac angiography with fractional flow reserve measurement allows for the anatomical and functional assessment of CAD. Given the invasive nature of invasive cardiac angiography and the risks of procedure-related complications, research has focused upon noninvasive methods for anatomical and functional measures of CAD. As such, there is growing interest in the development of hybrid imaging because it may provide incremental diagnostic information over each imaging modality alone. We will provide an overview of the evidence to date on the anatomical and functional stratification of CAD and current hybrid techniques.
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http://dx.doi.org/10.1586/14779072.2013.837755DOI Listing
October 2013

No cardioprotective benefit of ischemic postconditioning in patients with ST-segment elevation myocardial infarction.

J Interv Cardiol 2013 Oct;26(5):482-90

Department of Cardiac Sciences and Libin Cardiovascular Institute of Alberta, University of Calgary, Calgary, Alberta, Canada.

Background: Postconditioning is a potential cardioprotective strategy that has demonstrated conflicting and variable reductions in infarct size in human trials.

Objectives: To determine whether postconditioning could increase the extent of myocardial salvage in patients with acute ST-segment elevation myocardial infarction undergoing primary percutaneous coronary intervention (PPCI).

Methods: One hundred two patients (aged 57 ± 11 years; 88% male) were randomly assigned to a postconditioning or standard protocol. Cardiovascular magnetic resonance imaging was performed 3 days after PPCI to measure the volumetric extent of myocardial necrosis and the area at risk.

Results: With similar time-to-reperfusion (170 ± 84 minutes in the postconditioning group vs. 150 ± 70 minutes in the standard group, P = 0.22), the myocardial salvage index was not significantly different between the postconditioned group and the control group, averaging 42 ± 22% vs. 33 ± 21%, respectively (P = 0.08). Furthermore, postconditioning was not associated with a smaller infarct size compared to controls (13 ± 7 g/m(2) vs. 15 ± 8 g/m(2), respectively, P = 0.18).

Conclusions: Postconditioning does not significantly increase myocardial salvage or reduce infarct size in patients with STEMI undergoing PPCI. However, the possibility of a more modest impact of postconditioning cannot be excluded with our sample size.
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http://dx.doi.org/10.1111/joic.12064DOI Listing
October 2013

CT vs SPECT: CT is the first-line test for the diagnosis and prognosis of stable coronary artery disease.

J Nucl Cardiol 2013 Jun;20(3):465-72

Department of Medicine (Cardiology), University of Ottawa Heart Institute, 40 Ruskin Street, Ottawa, ON, K1Y 4W7, Canada.

Non-invasive cardiac imaging is pivotal in the diagnosis and prognosis of patients with stable CAD. Nuclear SPECT, PET, stress echocardiography and more recently cardiac magnetic resonance imaging have been utilized with excellent diagnostic accuracy. However, along with their inherent individual limitations, most modalities detect ischemia but lack the ability to define coronary anatomy or evaluate for subclinical atherosclerosis. A modality that not only accurately diagnoses obstructive CAD and also facilitates early identification of non-obstructive CAD may be of interest because it may allow for earlier aggressive risk factor modification and primary prevention. Cardiac computerized tomographic angiography (CCTA) has the potential to accurately detect or exclude luminal stenosis, as well as identify and quantify subclinical atherosclerosis in the absence if luminal narrowing. However CCTA, being a relatively a new modality, has less supporting evidence when compared to more mature modalities such as SPECT. Therefore, the question that begs to be addressed is whether CCTA can be utilized as a first line test in establishing the diagnosis and prognosis of CAD.
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http://dx.doi.org/10.1007/s12350-013-9690-6DOI Listing
June 2013

Atrial remodeling in newly diagnosed drug-naive hypertensive subjects.

Echocardiography 2013 Jul 30;30(6):627-33. Epub 2013 Jan 30.

Division of Cardiology, UBC, Vancouver General Hospital, Vancouver, British Columbia,, Canada.

Background: Systemic hypertension is a major risk factor for heart disease and stroke. Data regarding temporal relationship of left atrial (LA) remodeling to onset of hypertension are sparse. We aimed to quantitate LA structural and functional remodeling in newly diagnosed hypertensive patients.

Method: We prospectively identified 380 patients with newly diagnosed systemic hypertension naive to drug therapy, and 380 age-matched control subjects without any history or evidence of hypertension. History or evidence of prior cardiovascular events, congenital or valvular heart disease, and renal dysfunction were exclusion criteria. Prevalence of LA enlargement, LA mechanical dysfunction expressed in total emptying fraction, left ventricular (LV) diastolic dysfunction, LV hypertrophy, and their interrelationships were assessed.

Results: Of the 380 newly diagnosed hypertensive patients, 285 (75%) had LA enlargement, 308 (81%) had LA mechanical dysfunction, and 19 (5%) had LVH. Diastolic dysfunction was present in 334 (88%) of the patients. Compared to the controls, the hypertensive group had larger maximal, minimal, and pre-A LA volumes (all P < 0.001). Total and active LA emptying fraction were significantly reduced (both P < 0.001). Total LA emptying fraction was strongly associated with systolic blood pressure [per 10 mmHg, HR 0.94 (0.89-0.98); P < 0.001], with stepwise decrease in LA emptying fraction of 6%, 10%, and 16% from the lowest (141-150 mmHg) to the top tertile of systolic blood pressure (>160 mmHg).

Conclusion: In this drug-naive cohort with newly diagnosed hypertension, LA structural and functional remodeling, and LV diastolic dysfunction were common findings prior to initiation of drug treatment. LVH was uncommon. Impairment of LA mechanical function was evident even in the mildly hypertensive subgroup.
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http://dx.doi.org/10.1111/echo.12119DOI Listing
July 2013
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