Saturday, March 29, 2014

Assessment of global myocardial perfusion reserve using cardiovascular magnetic resonance of coronary sinus flow at 3 Tesla.

BACKGROUND: Despite increasing clinical use, there is limited data regarding regadenoson in stress perfusion cardiovascular magnetic resonance (CMR). In particular, given its long half-life the optimal stress protocol remains unclear. Although Myocardial Perfusion Reserve (MPR) may provide additive prognostic information, current techniques for its measurement are cumbersome and challenging for routine clinical practice.The aims of this study were: 1) To determine the feasibility of MPR quantification during regadenoson stress CMR by measurement of Coronary Sinus (CS) flow; and 2) to investigate the role of aminophylline reversal during regadenoson stress-CMR.
METHODS: 117 consecutive patients with possible myocardial ischemia were prospectively enrolled. Perfusion imaging was performed at 1 minute and 15 minutes after administration of 0.4 mg regadenoson. A subgroup of 41 patients was given aminophylline (100 mg) after stress images were acquired. CS flow was measured using phase-contrast imaging at baseline (pre CS flow), and immediately after the stress (peak CS flow) and rest (post CS flow) perfusion images.
RESULTS: CS flow measurements were obtained in 92% of patients with no adverse events. MPR was significantly underestimated when calculated as peak CS flow/post CS flow as compared to peak CS flow/pre CS flow (2.43 +/- 0.20 vs. 3.28 +/- 0.32, p = 0.03). This difference was abolished when aminophylline was administered (3.35 +/- 0.44 vs. 3.30 +/- 0.52, p = 0.95). Impaired MPR (peak CS flow/pre CS flow <2) was associated with advanced age, diabetes, current smoking and higher Framingham risk score.
CONCLUSIONS: Regadenoson stress CMR with MPR measurement from CS flow can be successfully performed in most patients. This measurement of MPR appears practical to perform in the clinical setting. Residual hyperemia is still present even 15 minutes after regadenoson administration, at the time of resting-perfusion acquisition, and is completely reversed by aminophylline. Our findings suggest routine aminophylline administration may be required when performing stress CMR with regadenoson.

J Cardiovasc Magn Reson. 2014 Mar 27;16(1):24

Friday, March 21, 2014

Twenty four hour imaging delay improves viability detection by Tl-201 myocardial perfusion scintigraphy.

OBJECTIVE: Since twenty-four-hour imaging by Tl-201 myocardial perfusion scintigraphy has been introduced as an effective additional procedure, the aim of this study was to compare this method's result with only rest redistribution procedure in the diagnosis of myocardial viability.
METHODS: Thirty patients (Seven female, 23 male; mean: 59.8 ± 10.7, 55.8-63.8 years old) with diagnosis of coronary artery disease were involved in this study. All patients had anamnesis of previous myocardial infarction and/or total occlusion of any main artery in the coronary angiography. Myocardial perfusion scintigraphy with Tl-201 with rest four hour (early) redistribution and 24 hour delayed redistribution protocol were performed to all of the patients. The images were evaluated according to 17 segment basis by an experienced nuclear medicine physician and improvement of a segment by visual interpretation was considered as viable myocardial tissue.
RESULTS: Viability was found at 52 segments in the early redistribution images and additional 18 segments in the 24 hour delayed redistribution images on segment basis in the evaluation of 510 segments of 30 patients. On per patient basis, among the 26 patients who had viable tissue, 14 (54%) had additional improvement in 24 hour delayed images. Three (12%) patients had viable tissue in only 24 hour delayed images.
CONCLUSION: Delayed imaging in Tl-201 MPS is a necessary application for the evaluation of viable tissue according to considerable number of patients with additional improvement in 24 hour images in our study, which is restricted to the patients with myocardial infarct.

Rev Bras Cir Cardiovasc. 2013 Dec;28(4):498-503

Wednesday, March 19, 2014

Experience of low-dose aminophylline use to relieve minor adverse effects of dipyridamole

BACKGROUND: aminophylline is widely used to reverse dipyridamole-related adverse effects during stress myocardial perfusion imaging (MPI).

METHODS: 2,250 consecutive patients were evaluated.

RESULTS: No severe adverse events were observed. Low-dose (25 mg) aminophylline relieved symptoms in 98.8% of patients with mild adverse events. An additional 25 mg aminophylline reversed the moderate adverse events.

CONCLUSION: aminophylline at 25 mg IV is sufficient to relieve nearly all dipyridamole-related adverse events observed during stress MPI.

J Nucl Cardiol. 2014 Mar 14

Monday, March 17, 2014

Inappropriate utilization of SPECT myocardial perfusion imaging on the USA-Mexico border.

BACKGROUND: The ASNC published revised "Appropriate Use Criteria" for SPECT MPI in 2009.

METHODS: 420 SPECT MPI studies were evaluated.

RESULTS: 86% were appropriate and 14% inappropriate. Younger females were more likely to have an inappropriate test. Diabetics and patients with chest pain were less likely to have an inappropriate test. Community primary care providers were less likely than community cardiologists to order an inapproprate test.

CONCLUSIONS: young women are more likely to have an inappropriate nuclear myocardial perfusion imaging scan compared to other demographic groups. Cardiologists were more likely to order inappropriate tests compared to primary care providers.

J Nucl Cardiol. 2014 Mar 14;

Friday, March 14, 2014

Optimisation of reconstruction-reprojection-based motion correction for cardiac SPECT.

OBJECTIVE: Cardiac motion is a challenging cause of image artefacts

METHODS: Two slightly different implementations of reconstruction-reprojection-based motion correction techniques were optimised for effective, good-quality motion correction and then compared with each other. The first of these methods (Method 1) was the traditional reconstruction-reprojection motion correction algorithm, where the motion correction is done in projection space, whereas the second algorithm (Method 2) performed motion correction in reconstruction space.

RESULTS: Method 2 performed slightly better overall than Method 1, but the difference between the two implementations was small. The execution time for Method 2 was much longer than for Method 1, which limits its clinical usefulness. The mutual information cost function gave clearly the best results for all three motion sets for both correction methods. Three iterations were sufficient for a good quality correction using Method 1.

CONCLUSIONS: The traditional reconstruction-reprojection-based method with three update iterations and mutual information cost function is a good option for motion correction in clinical myocardial perfusion SPECT.

Ann Nucl Med. 2014 Mar 6

Thursday, March 13, 2014

Myocardial Tissue Perfusion Predicts the Evolution of Fragmented QRS

BACKGROUND: Fragmented QRS complex (fQRS) is associated with worse outcomes in several cardiovascular conditions.

METHODS: 401 consecutive patients with STEMI underwent primary PCI. Patients were categorized into two subgroups according to persistence or new-onset of fQRS (Group 1) and absence or resolution of fQRS (Group 2).

RESULTS: Patients in group 1 showed older age, higher rate of smoking, lower HDL-cholesterol, lower LVEF, higher angina-to-door time, higher TIMI frame count, and high rate of patients with MBG <3 compared to patients with group 2 (P < 0.05). In correlation analysis, LVEF showed positive correlation with myocardial blush grade (MBG, r = 0.448, P < 0.001) and negative correlation with the number of leads with fQRS (r = -0.335, P < 0.001). In multivariate regression analysis, new-onset or persistance of fQRS after primary PCI is significantly associated with MBG, peak CK-MBl, pre-PCI fQRS, and smoking.

CONCLUSION: Our findings showed that despite complete ST-segment resolution in all patients, fQRS is independently associated with impaired microvascular myocardial perfusion. So, fQRS, as a simple and easily available noninvasive marker, may be useful in stratification of high-risk patients with increased extent of infarcted myocardium who underwent primary PCI.

Ann Noninvasive Electrocardiol. 2014 Mar 4

COMMENT: not surprisingly, smoking was associated with higher risk

Tuesday, March 11, 2014

The use of a learning community and online evaluation of utilization for SPECT myocardial perfusion imaging.

This study found that a self-directed quality improvement web based community in conjunction with a software quality improvement program was able to reduce "inappropriate" ordering of tests by 50% within a year. JACC Cardiovasc Imaging. 2013 Jul;6(7):823-9

COMMENT: it appears from this study that all that's needed nowadays is a computer to decide what tests you need. Why even see a doctor? 

Sunday, March 9, 2014

Evaluation of Suspected Ischemic Heart Disease in Symptomatic Women.

Evaluation of Suspected Ischemic Heart Disease in Symptomatic Women.
Can J Cardiol. 2013 Sep 28;
Authors: Shaw LJ, Tandon S, Rosen S, Mieres JH

There is a wealth of evidence about the role of a variety of diagnostic testing modalities to define coronary artery disease (CAD) risk in women presenting for evaluation of suspected myocardial ischemia. The exercise electrocardiogram (ECG) is the core index procedure, which can define risk in women capable of performing maximal exercise. Stress imaging, using echocardiography or myocardial perfusion single-photon emission computed tomography/positron emission tomography, is useful for symptomatic women with an abnormal resting ECG or for those who are functionally disabled. For women with low-risk stress imaging findings, there is a very low risk of CAD events, usually < 1%. There is a gradient relationship between the extent and severity of inducible abnormalities and CAD event risk. Women at high risk are those defined as having moderate to severely abnormal wall motion or abnormal perfusion imaging findings. In addition to stress imaging, the evidence of the relationship between CAD extent and severity and prognosis has been clearly defined with coronary computed tomographic angiography. In women, prognosis for those with mild but nonobstructive CAD is higher when compared with those without any CAD. The current evidence base clearly supports that women presenting with chest pain can benefit from one of the commonly applied diagnostic testing modalities.

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Assessing clinical impact of myocardial perfusion studies: ischemia or other prognostic indicators?

Assessing clinical impact of myocardial perfusion studies: ischemia or other prognostic indicators?
Curr Cardiol Rep. 2014 Apr;16(4):465
Authors: Miller TD, Askew JW, Herrmann J

One of the major strengths of nuclear myocardial perfusion imaging (MPI) is the robust prognostic databases from observational studies demonstrating significantly different outcomes in patients with low-risk vs high-risk scans. The severity of the MPI defect can be semi-quantitated using the summed stress score (SSS) and summed difference score (SDS). SSS is more strongly associated with mortality, whereas SDS is the better predictor of subsequent coronary angiography and revascularization. The strength of MPI variables as prognostic indicators decreases when adjusted for prognostically important clinical and stress test variables. Nonetheless, most studies of general patient populations have demonstrated that MPI adds incremental prognostic value to clinical and stress test information. In contrast to these positive results from observational studies, the application of MPI ischemia as a treatment guide in several recent trials (DIAD, WOMEN, COURAGE, BARI 2D, STICH) has largely failed to identify patient subsets with improved outcome. This issue will continue to be investigated in the ongoing PROMISE and ISCHEMIA trials.

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Friday, March 7, 2014

Advanced imaging of cardiac sarcoidosis.

Advanced imaging of cardiac sarcoidosis.
J Nucl Med. 2014 Jan;55(1):99-106
Authors: Schatka I, Bengel FM

Sarcoidosis is a systemic granulomatous disease of unknown etiology. Cardiac involvement may occur, leading to an adverse outcome. Although early treatment to improve morbidity and mortality is desirable, sensitive and accurate detection of cardiac sarcoidosis remains a challenge. Accordingly, interest in the use of advanced imaging such as cardiac MR and PET with (18)F-FDG is increasing in order to refine the clinical workup. Although the field is still facing challenges and uncertainties, this article presents a summary of clinical background and the current state of diagnostic modalities and treatment of cardiac sarcoidosis.

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Assessment of myocardial perfusion with MRI using a modified dual bolus method.

Assessment of myocardial perfusion with MRI using a modified dual bolus method.
Physiol Meas. 2014 Feb 27;35(4):533-547
Authors: Husso M, Sipola P, Kuittinen T, Manninen H, Vainio P, Hartikainen J, Saarakkala S, Töyräs J, Kuikka J

Quantification of regional myocardial blood flow (rMBF) with first-pass magnetic resonance imaging (FP-MRI) requires two contrast agent injections (dual bolus technique), inducing error in the determined rMBF if the injections differ. We hypothesize that using input and residue curves of the same injection would be more reliable. We aim to introduce and evaluate a novel method to correct the high concentration arterial input function (AIF) for determination of rMBF. Sixteen patients with non-Hodgkin's lymphoma were examined before and after chemotherapy. The input function was solved by correcting initial high concentration AIF using the ratio of low and high contrast AIF areas, normalized by corresponding heart rates (modified dual bolus method). For comparison, the scaled low contrast AIF was used as an input function (dual bolus method). Unidirectional transfer coefficient K(trans) was calculated using both methods. K(trans)-values determined with the dual bolus (0.81 ± 0.32 ml g(-1) min(-1)) and modified dual bolus (0.77 ± 0.42 ml g(-1) min(-1)) methods were in agreement (p = 0.21). Mean K(trans)-values increased from 0.76 ± 0.43 to 0.89 ± 0.55 ml g(-1) min(-1) after chemotherapy (p = 0.17). The modified dual bolus technique agrees with the dual bolus technique (R2 = 0.899) when the low and high contrast injections are similar. However, when this is not the case, the modified dual bolus technique may be more reliable.

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Assessing the Prognostic Implications of Myocardial Perfusion Studies: Identification of Patients at Risk vs Patients who May Benefit from Intervention?

Assessing the Prognostic Implications of Myocardial Perfusion Studies: Identification of Patients at Risk vs Patients who May Benefit from Intervention?
Curr Cardiol Rep. 2014 Apr;16(4):472
Authors: Cremer P, Hachamovitch R

Stress myocardial perfusion imaging (MPI) has a well-established role in improving risk stratification. Recent analyses, compared with older data, suggest that the yield of stress MPI has decreased. In part, this trend relates to testing patients with heterogeneous, but improved, risk factor modification. In this setting, positron emission tomography with myocardial flow reserve enhances risk stratification as it reflects the end result of atherosclerosis. Recent studies have also emphasized the clinical impact of incremental risk stratification by assessing net reclassification improvement (NRI). Previous retrospective studies have favored an ischemic threshold to select patients that benefit from revascularization, but this finding has not been corroborated in randomized trials. However, no large randomized trial has directly tested a strategy of revascularization for patients with at least a moderate amount of ischemia at risk. Unfortunately, even when faced with a significantly abnormal MPI result, subsequent action is too often absent.

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Quantitative three-dimensional cardiovascular magnetic resonance myocardial perfusion imaging in systole and diastole.

Quantitative three-dimensional cardiovascular magnetic resonance myocardial perfusion imaging in systole and diastole.
J Cardiovasc Magn Reson. 2014 Feb 24;16(1):19
Authors: Motwani M, Kidambi A, Sourbron S, Fairbairn TA, Uddin A, Kozerke S, Greenwood JP, Plein S

BACKGROUND: Two-dimensional (2D) perfusion cardiovascular magnetic resonance (CMR) remains limited by a lack of complete myocardial coverage. Three-dimensional (3D) perfusion CMR addresses this limitation and has recently been shown to be clinically feasible. However, the feasibility and potential clinical utility of quantitative 3D perfusion measurements, as already shown with 2D-perfusion CMR and positron emission tomography, has yet to be evaluated. The influence of systolic or diastolic acquisition on MBF estimates, diagnostic accuracy and image quality is also unknown for 3D-perfusion CMR. The purpose of this study was to establish the feasibility of quantitative 3D-perfusion CMR for the detection of coronary artery disease (CAD) and to compare systolic and diastolic estimates of myocardial blood flow (MBF).
METHODS: Thirty-five patients underwent 3D-perfusion CMR with data acquired at both end-systole and mid-diastole. MBF and myocardial perfusion reserve (MPR) were estimated on a per patient and per territory basis by Fermi-constrained deconvolution. Significant CAD was defined as stenosis >=70% on quantitative coronary angiography.
RESULTS: Twenty patients had significant CAD (involving 38 out of 105 territories). Stress MBF and MPR had a high diagnostic accuracy for the detection of CAD in both systole (area under curve [AUC]: 0.95 and 0.92, respectively) and diastole (AUC: 0.95 and 0.94). There were no significant differences in the AUCs between systole and diastole (p values >0.05). At stress, diastolic MBF estimates were significantly greater than systolic estimates (no CAD: 3.21 +/- 0.50 vs. 2.75 +/- 0.42 ml/g/min, p < 0.0001; CAD: 2.13 +/- 0.45 vs. 1.98 +/- 0.41 ml/g/min, p < 0.0001); but at rest, there were no significant differences (p values >0.05). Image quality was higher in systole than diastole (median score 3 vs. 2, p = 0.002).
CONCLUSIONS: Quantitative 3D-perfusion CMR is feasible. Estimates of MBF are significantly different for systole and diastole at stress but diagnostic accuracy to detect CAD is high for both cardiac phases. Better image quality suggests that systolic data acquisition may be preferable.

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Wednesday, March 5, 2014

Noncalcified Coronary Plaque Volumes in Healthy People with a Family History of Early-Onset Coronary Artery Disease.

Noncalcified Coronary Plaque Volumes in Healthy People with a Family History of Early-Onset Coronary Artery Disease.
Circ Cardiovasc Imaging. 2014 Feb 27;
Authors: Kral BG, Becker LC, Vaidya D, Yanek LR, Qayyum R, Zimmerman SL, Dey D, Berman DS, Moy TF, Fishman EK, Becker DM

BACKGROUND: -Although age and sex distributions of calcified plaque (CCP) have been well described in the general population, noncalcified plaque (NCP) distributions remain unknown. This is important because NCP is a putative precursor for clinical CAD and could serve as a sentinel for aggressive primary prevention, especially in higher risk populations. We examined the distributions of NCP and CCP in healthy 30-74 year old individuals from families with early-onset coronary artery disease (CAD).
METHODS AND RESULTS: -Participants in the GeneSTAR family study (N=805), mean age 51.1 ± 10.8 years, 56% female, were screened for CAD risk factors and for coronary plaque using dual-source CT angiography. Plaque volumes (mm(3)) were quantified using a validated automated method. The prevalence of coronary plaque was 57.8% in males and 35.8% in females (p<0.0001). NCP volume increased with age (p<0.001) and was higher in males than females (p<0.001). Although NCP, as a percent of total plaque, was inversely related to age (p<0.01), NCP accounted for most of the total plaque volume at all ages, especially in males and females <55 years (>70% and >80%, respectively). Higher Framingham risk was associated with the number of affected vessels (p<0.01) but 44% of males and 20.8% of females considered intermediate risk had left main and/or 3-vessel disease involvement.
CONCLUSIONS: -The majority of coronary plaque was noncalcified, particularly in younger individuals. These findings support the importance of assessing family history and suggest that early primary prevention interventions may be warranted at younger ages in families with early onset CAD.

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Monday, March 3, 2014

Correlation between transient ischemic dilatation (TID) and coronary artery disease in Saudi male patients.

Correlation between transient ischemic dilatation (TID) and coronary artery disease in Saudi male patients.
J Saudi Heart Assoc. 2014 Jan;26(1):1-5
Authors: Aldhilan A, Syed GM, Suleiman I, Al Zaibag M, Fielding H

OBJECTIVE: A high transient ischemic dilatation ratio (TID) for the left ventricle (LV) from a gated myocardial perfusion imaging (G-MPI) study is widely believed to be associated with significant coronary artery disease (CAD). We have investigated the relationship between TID and CAD for our male Saudi Arabian patient population.
METHODS: In this retrospective study, all male Saudi Arabian patients who underwent a two-day G-MPI study using Tc99m MIBI during the year 2011 having a TID ⩾ 1.20 were included. Quantitative perfusion and gated parameters were obtained using Cedar Sinai's AutoQuant software version 3.0, 2003, Means of summed stress scores, summed rest scores and summed difference scores (SSS, SRS, SDS, respectively), stress and rest ejection fraction (EF) were calculated. Visual interpretation was performed to classify the perfusion as normal, fixed, mixed (fixed and reversible defects), single reversible or multiple reversible defects. Coronary angiograms were assessed as normal with no CAD, single vessel, two-vessel or three-vessel disease. Correlations between the TID and other parameters were studied using analysis of variance (ANOVA) with IBM-SPSS version 20.
RESULTS: A total of 52 male patients had a high TID of ⩾1.20 (mean 1.30 ± 0.13). Ten patients had a SSS of 0-3 and 16 were classified as normal by visual assessment. Stress EF (mean 50.4 ± 12%) was lower than the rest EF (mean 56.6 ± 12.8%) with the difference being statistically significant (Students paired t-test, p = 0.001). Angiography results were available in 44 patients, 3 having a normal angiogram, 24 having three vessel disease, 7 having two vessel disease and 10 having one vessel disease. Five patients with normal perfusion and SSS = 0-3 had CAD as seen on a coronary angiography. CAD on coronary angiography showed a significant correlation with perfusion abnormalities as assessed by visual interpretation (p = 0.002). TID showed a significantly correlation with both perfusion abnormalities (p = 0.009), as assessed by visual interpretation, and with Summed difference scores, SDS (p = 0.000).
CONCLUSION: A high TID on G-MPI was a very sensitive indicator of significant CAD. In patients with normal perfusion and high TID further workup is warranted.

24578594 [PubMed]
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Sites of latest mechanical activation as assessed by SPECT myocardial perfusion imaging in ischemic and dilated cardiomyopathy patients with LBBB.

Sites of latest mechanical activation as assessed by SPECT myocardial perfusion imaging in ischemic and dilated cardiomyopathy patients with LBBB.
Eur J Nucl Med Mol Imaging. 2014 Feb 28;
Authors: Lin X, Xu H, Zhao X, Chen J

OBJECTIVE: Sites of latest mechanical activation (SOLA) have been recognized as optimal left-ventricular (LV) lead positions for cardiac resynchronization therapy (CRT). This study was aimed to investigate SOLA in ischemic cardiomyopathy (ICM) and dilated cardiomyopathy (DCM) patients with left bundle branch block (LBBB).
METHODS: Sixty-four consecutive LBBB patients (47 DCM, 17 ICM), who met the standard indications for CRT and underwent resting SPECT myocardial perfusion imaging (MPI), were selected. Phase analysis was used to assess LV dyssynchrony and SOLA. The Emory Cardiac Toolbox was used to measure perfusion defects. LV dyssynchrony and SOLA were compared between the DCM patients with wide (≥150 ms) and moderate (120-150 ms) QRS durations (QRSd). The relationship between SOLA and perfusion defects was analyzed in the ICM patients.
RESULTS: The DCM patients with wide QRSd had significantly more LV dyssynchrony than those with moderate QRSd. Lateral SOLA were significantly more frequent in the DCM patients with wide QRSd than those with moderate QRSd (96 % vs. 62 %, p = 0.010). In the ICM patients, SOLA were either in the scar segments (82 %) or in the segments immediately adjacent to the scar segments (18 %), regardless of QRSd.
CONCLUSION: Lateral SOLA were more frequent in the DCM patients with wide QRSd than those with moderate QRSd. Such relationship was not observed in the ICM patients, where SOLA were associated with scar location rather than QRSd. These findings support the use of SPECT MPI to aid the selection of potential CRT responders and guide LV lead placement.

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Computed Tomography Assessment of Hemodynamic Significance of Coronary Artery Disease: CT Perfusion, Contrast Gradients by Coronary CTA, and Fractional Flow Reserve Review.

Computed Tomography Assessment of Hemodynamic Significance of Coronary Artery Disease: CT Perfusion, Contrast Gradients by Coronary CTA, and Fractional Flow Reserve Review.
J Thorac Imaging. 2014 Feb 26;
Authors: Loewe C, Stadler A

The need for functional estimation of the relevance of stenosis to guide appropriate treatment in coronary artery disease has recently been shown. Invasive coronary angiography (CA) with invasive measurement of the pressure gradient in patients with coronary stenoses becomes the method of choice for treatment decision-making in invasive cardiology. Coronary computed tomography angiography (CCTA) was established several years ago as a noninvasive alternative to invasive CA; it is used primarily to exclude coronary artery disease and has shown a very high negative predictive value in this regard. During the last several years, in an effort to obtain functional information, CCTA has received much attention. The rationale for this is that with the functional information provided by CT, the positive predictive value for "relevant" stenoses should be improved. In this article, the history and limitations of anatomic grading of coronary stenoses will be discussed. Furthermore, shifts in the treatment paradigm in modern cardiology will be introduced, as well as an overview of the currently used invasive methods to assess the "relevance" of stenosis. The current role and still-existing limitations of CCTA, as well as the systematic problems in comparing CA and CCTA, are addressed. As CCTA is a highly innovative technique, new innovations are currently under clinical evaluation, including myocardial perfusion imaging, attenuation gradient measurement, and assessment of fractional flow reserve with CT. This review article will mainly focus on the technical background of these techniques and the status of their clinical implementation and will attempt to provide some suppositions about the possible future role of these new innovations.

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Testosterone deficiency syndrome and cardiovascular health: An assessment of beliefs, knowledge and practice patterns of general practitioners and cardiologists in Victoria, BC.

Testosterone deficiency syndrome and cardiovascular health: An assessment of beliefs, knowledge and practice patterns of general practitioners and cardiologists in Victoria, BC.
Can Urol Assoc J. 2014 Jan;8(1-2):30-3
Authors: Wallis CJ, Brotherhood H, Pommerville PJ

INTRODUCTION: Testosterone deficiency syndrome (TDS) has been shown to be an independent cardiovascular risk factor and a predisposing factor for metabolic syndrome. As general practitioners and cardiologists primarily care for these patients, we sought to assess their knowledge, beliefs and practice patterns with respect to TDS and cardiac health.
METHODS: We distributed a questionnaire to all 20 cardiologists and a cohort of 128 family practitioners in Victoria, British Columbia. Of the 13 questions, 10 assessed knowledge and beliefs on TDS and 3 assessed current practice patterns.
RESULTS: Most respondents believed that TDS is a medical condition (66.7%) and could negatively affect body composition (62%), but a similar majority was unsure whether it was a cardiac risk factor (66.7%). While most believed that testosterone replacement therapy (TRT) could improve exercise tolerance (62%), most were unsure if it was beneficial in cardiac patients. Cardiologists were significantly less likely to believe that TRT was beneficial in preventing recurrent myocardial infarction and improving myocardial perfusion (p = 0.0133, 0.00186, respectively). The vast majority (88%) did not screen cardiac patients for TDS. If a patient was identified as having TDS, only10% of those surveyed would refer these patients to a urologist.
CONCLUSION: Despite its prevalence in cardiac patients, TDS is not well-understood by general practitioners and cardiologists; they lack knowledge on its deleterious cardiovascular effects. In their role as men's health advocates, urologists should educate our colleagues regarding the correlation between TDS and cardiovascular mortality and risk factors. Limitations of this study include small sample size and restricted geographic scope.

24578740 [PubMed]
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Combined Supine and Prone Myocardial Perfusion Single-Photon Emission Computed Tomography With a Cadmium Zinc Telluride Camera for Detection of Coronary Artery Disease.

Combined Supine and Prone Myocardial Perfusion Single-Photon Emission Computed Tomography With a Cadmium Zinc Telluride Camera for Detection of Coronary Artery Disease.
Circ J. 2014 Feb 25;
Authors: Nishiyama Y, Miyagawa M, Kawaguchi N, Nakamura M, Kido T, Kurata A, Kido T, Ogimoto A, Higaki J, Mochizuki T

Background: Myocardial perfusion SPECT (MPS) traditionally requires the patient to be in the supine position, but diaphragmatic attenuation of the inferior wall reduces test specificity. The aim of this study was to assess the feasibility of combined MPS in the supine and prone positions using a novel cadmium zinc telluride (CZT) camera. Methods and Results: A total of 276 consecutive patients with suspected/known coronary artery disease (CAD) who underwent single-day (99m)Tc-tetrofosmin or (99m)Tc-sestamibi stress/rest CZT SPECT, were enrolled in the study. Seventy-six underwent coronary angiography. Five-minute scan in the supine (S) position and thereafter in the prone (P) position produced images that were visually interpreted to obtain summed stress (SSS) and rest (SRS) scores. A combined stress score (C-SSS) was calculated by grouping anterior perfusion defects observed during supine imaging with inferior half segments observed during prone imaging. The SSS for the supine, prone, and combined protocols were 9±8, 7±8, and 7±8, respectively (P<0.0001). The SRS were 5±8, 4±7, and 6±7, respectively (P=0.005). The area under the ROC curve for the S-SSS, P-SSS, and C-SSS scores was 0.815 (95% CI: 0.713-0.917), 0.813 (0.711-0.914), and 0.872 (0.783-0.961), respectively. Corresponding sensitivities and specificities for detecting CAD were 87% and 50%, 80% and 77%, and 85% and 82%, respectively. C-SSS had significantly better specificity and accuracy than S-SSS (P<0.05). Conclusions: Combined imaging with a CZT camera is suitable for routine clinical MPS and provides greater diagnostic accuracy than supine imaging alone.

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