Tareq Alyousef

Soft tissue attenuation patterns in stress myocardial perfusion SPECT images: A comparison between supine and upright acquisition systems

BackgroundSoft tissue attenuation patterns and their interaction with body habitus and gender in Single Photon Emission Computed Tomography (SPECT)-myocardial perfusion imaging (MPI) of upright patient-position acquisition systems are not well described.MethodsIn a retrospective cross-sectional study, we compared the prevalence and patterns of soft tissue attenuation in two groups of normal SPECT-MPI studies acquired by supine (nxa0=xa0263) vs upright (nxa0=xa0212) acquisition systems.ResultsAttenuation patterns observed in the study population were: anterior (22.3%), inferior (51.6%) and lateral (18.1%). Anterior attenuation was significantly less in those imaged upright (6.1% vs 35.4%), Pxa0<xa0.001; particularly among women (9.5% vs 50.7%), Pxa0<xa0.001. Inferior attenuation was more common among women imaged upright (49.5% vs 13.5%), Pxa0<xa0.001; but was not affected by imaging position among men. Lateral attenuation was more prevalent in the upright group (24.1% vs 13.3%), Pxa0=xa0.002; and had a strong association with female gender (Pxa0<xa0.001) and BMIxa0≥xa030 (Pxa0<xa0.001).ConclusionsUpright SPECT-MPI acquisition is associated with a unique attenuation pattern which is vastly different than the supine position. Female gender strongly impacted this attenuation pattern, particularly obese women. Our study is the first to describe, in details, the attenuation patterns with upright imaging and is critical for the accurate interpretation of SPECT-MPI acquired with upright systems.

The Prognostic Value of Undetectable Highly Sensitive Cardiac Troponin I in Patients With Acute Pulmonary Embolism

BACKGROUNDnElevated cardiac troponin levels have been shown to be associated with adverse outcomes in patients with acute pulmonary embolism (PE). However, few data address the management implications of undetectable cardiac troponin I (cTnI) using a highly sensitive assay. We hypothesized that undetectable cTnI predicts very low in-hospital adverse event rates.nnnMETHODSnIn a retrospective cohort study, we classified patients with confirmed acute PE according to cTnI detectability into cTnI+ (≥ 0.012 ng/mL) and cTnI- (< 0.012 ng/mL) groups. The Pulmonary Embolism Severity Index (PESI) was used for clinical risk determination. The primary outcome was a composite of hard events defined as in-hospital death, CPR, or thrombolytic therapy. The secondary outcome was a composite of soft events defined as ICU admission or inferior vena cava filter placement.nnnRESULTSnAmong 298 consecutive patients with confirmed acute PE, 161 (55%) were cTnI+ and 137 (45%) cTnI-. No deaths occurred in the cTnI- group vs nine (6%) in the cTnI+ group (P = .004). No hard events were observed in the cTnI- group vs 15 (9%) in the cTnI+ group (P < .001). Soft events were observed at a lower rate in the cTnI- group (21[15%] vs 69 [43%], P < .001). Patients in the cTnI- group had a higher survival rate free of hard (P = .001) or soft (P < .001) events, irrespective of clinical risk. Furthermore, cTnI provided incremental prognostic value beyond clinical, ECG, and imaging data (P < .001).nnnCONCLUSIONSnHighly sensitive cTnI assay provides an excellent prognostic negative predictive value; thus, it plays a role in identifying candidates for out-of-hospital treatment of acute PE.

Tissue Doppler imaging for diagnosis of coronary artery disease: a systematic review and meta-analysis

Global and regional left ventricular (LV) systolic dysfunction is a marker of coronary artery disease (CAD), which is conventionally assessed using two-dimensional echocardiography. Tissue Doppler imaging (TDI) has emerged as an adjunct tool in the diagnosis of regional wall motion abnormalities from CAD. We performed a systematic review and meta-analysis to assess the efficacy of TDI indices in the diagnosis of CAD. We searched MEDLINE and the Cochrane Library for controlled studies comparing TDI measurements in those with and without CAD as confirmed by coronary angiography. Meta-analyses of mean differences in TDI velocities between these populations were performed. Screening of titles and abstracts followed by full-text screening identified 8 studies. At rest, TDI was associated with a significant decrease in the pooled maximum systolic velocity among CAD patients compared to those without CAD [mean difference (MD): -0.66; 95% confidence interval (CI): -0.98 to −0.34]. There were no significant differences in maximum early and late diastolic velocities. Post-stress, TDI was associated with a significant decrease in maximum early diastolic velocity (MD: -1.91; 95% CI: -2.74 to −1.09) and maximum late diastolic velocity (MD: -1.57; 95% CI: -2.95 to −0.18) among CAD patients compared to those without CAD. There was no significant difference in maximum systolic velocity post-stress. Our results suggest that TDI may have a role in the evaluation of CAD. Future studies should evaluate the incremental value of TDI velocities over LV ejection fraction and two dimensional wall motion analysis in the detection of CAD and assessment of its severity. (Word Count: 249)

Soft Tissue Attenuation Patterns Associated with Upright Acquisition SPECT Myocardial Perfusion Imaging: A Descriptive Study

Background: Little is known about soft tissue attenuation artifacts when an upright patient-position SPECTmyocardial perfusion imaging (MPI) system is used. In this investigation we sought to describe the patterns and frequency of attenuation artifacts associated with this type of instruments and we explored the impact of gender and body habitus on these artifacts. Methods: In a cross-sectional study, we described the prevalence of various soft-tissue attenuation patterns in 212 normal SPECT-MPI studies acquired with an upright patient-position imaging system. Results: In these 212 normal, clinically-indicated, upright-acquisition SPECT-MPIs the attenuation patterns observed were: anterior (6.1%), inferior (63.7%) and lateral (24.1%). Though uncommon, anterior attenuation trended to being more prevalent among women [9.5% vs. 3.4%, P=0.07] and was independently associated with chest circumference. Lateral attenuation was more common among women [34.7% vs. 15.4%, p=0.001] and was strongly associated with obesity (p<0.001). Inferior attenuation was more prevalent among men than women (75.2% vs. 49.5% respectively, P<0.001). Conclusions: Soft-tissue attenuation artifacts are common in upright-acquisition SPECT-MPI. Recognizing the frequency of these attenuation patterns and their interaction with gender and body habitus is critical for the accurate interpretation of SPECT-MPI.

A Simple Validated Clinical Tool to Predict the Absence of Coronary Artery Disease in Patients With Systolic Heart Failure of Unclear Etiology

Coronary artery disease (CAD) is a major cause of systolic heart failure (HF). Identifying CAD as a cause of systolic HF has prognostic and treatment implications. Whether all patients with systolic HF of unclear etiology should undergo coronary angiography has been controversial. We sought to derive and validate a clinical prediction rule to exclude CAD as a cause of systolic HF. A derivation cohort was formed of consecutive patients who had undergone coronary angiography with a primary diagnosis of systolic HF of unclear etiology (ejection fraction <50%). Using multivariate logistic regression analysis, we derived a prediction rule for severe CAD (≥50% diameter stenosis in the left main, 3-vessel CAD, and 2-vessel CAD involving the proximal left anterior descending artery). The diagnostic performance of the defined prediction rule was prospectively validated in a separate cohort recruited from 2 institutions. Of the 124 patients in the derivation cohort, 27% had CAD, including 15% with severe CAD. The independent predictors of severe CAD included diabetes (odds ratio 5.1, pxa0= 0.005), electrocardiographic Q waves or left bundle branch block (odds ratio 3.8, pxa0= 0.02), and ≥2 nondiabetes risk factors: age (men ≥55 or women ≥65xa0years), dyslipidemia, hypertension, and tobacco use (odds ratio 4.8, pxa0= 0.02). Axa0prediction rule of having ≥1 independent predictor identified 97% of the patients with CAD and 100% of the patients with severe CAD. In the prospective validation cohort of 143 patients, the prediction rule had 98% sensitivity and 18% specificity for CAD but 100% sensitivity for severe CAD. In conclusion, a simple clinical prediction rule can accurately identify patients with CAD and eliminate the need for angiography in a substantial proportion of patients with systolic HF, with potentially significant cost savings and risk avoidance.

Ambulatory cardiac single-photon emission computed tomography at the primary care physician's office: a descriptive study.

Ambulatory cardiac single-photon emission computed tomography stress testing for the evaluation of coronary artery disease at the primary care physicians office is increasingly utilized without data supporting its safety. In this 2-year prospective pilot study of 1266 consecutive stress-myocardial perfusion imaging studies done in the primary care physicians office using a mobile nuclear cardiology laboratory, adverse events were mild and rare. There were no recorded events of myocardial infarction, serious arrhythmias, severe bronchospasm, hospitalization, or death. This suggests that this practice is safe in this population with these providers. This finding may not apply to a higher-risk population. Further evaluation of referral appropriateness and long-term prognostic value is needed.

The long-term prognostic value of highly sensitive cardiac troponin I in patients with acute pulmonary embolism

In patients with acute pulmonary embolism (PE), detectable levels of cardiac troponin I (cTnI) using a highly sensitive assay have been associated with increased in‐hospital mortality. We sought to investigate the impact of detectable cTnI on long‐term survival following acute PE.

Safety of endoscopic procedures after acute myocardial infarction: A systematic review

BACKGROUNDnThe management of patients who develop gastrointestinal (GI) bleeding after acute myocardial infarction (MI) is difficult due to concerns about possible cardiovascular complications. Gastroenterologists are often reluctant to perform endoscopic procedures despite urgent indications. We performed a systematic review of the literature to determine the safety of endoscopic procedures after MI.nnnMETHODSnWe searched MEDLINE, EMBASE and the Cochrane Central Register of Controlled trials for controlled clinical trials or case series examining the diagnostic efficacy and complications of esophagogastroduodenoscopy (EGD), colonoscopy and flexible sigmoidoscopy after MI. Title and abstract screening was followed by full-text review with subsequent data extraction of included studies.nnnRESULTSnA total of seven studies met inclusion criteria. Four studies evaluated safety and efficacy of EGD after MI. The reported complication rate ranged between 1-8%, with a large predominance of minor complications. We found one study addressing safety of flexible sigmoidoscopy that reported minor complications in two patients. We also identified one study addressing the safety of colonoscopy after MI, which showed a complication rate of 9%. Most of these complications were minor. A decision analysis was also included in this review.nnnCONCLUSIONSnOur review demonstrated that endoscopic procedures are safe and beneficial in stable patients with GI bleeding after recent MI and should be performed without a requisite delay. Unstable patients should undergo endoscopic procedures only in the intensive care setting, after stabilization and with close monitoring.

Tele-Cardiology in the Syrian War

![Figure][1] nnnn![Figure][1] nn![Figure][1] nnBefore the Syrian civil war started in 2011, Syria had relatively modern medical facilities and advanced cardiac care, especially in the majorxa0cities. Although rural areas might have been underserved, most of them were still within a 90

Bioprosthetic Mitral Valve Thrombosis Complicating Antiphospholipid Antibody Syndrome, Successfully Treated with Thrombolysis

The incidence of bioprosthetic valve thrombosis and related embolic complications is extremely rare, obviating the need for long‐term anticoagulation. As a result, experience in the diagnosis and treatment of bioprosthetic valve thrombosis is fairly limited. We report the first case of antiphospholipid antibody syndrome presenting as bioprosthetic mitral valve thrombosis, 15 months after valve replacement, and successfully treated with thrombolytic therapy.