CAR and CSTR Cardiac Computed Tomography (CT) Practice Guidelines: Part 2-Non-Coronary Imaging.

The cardiac computed tomography (CT) practice guidelines provide an updated review of the technological improvements since the publication of the first Canadian Association of Radiologists (CAR) cardiac CT practice guidelines in 2009. An overview of the current evidence supporting the use of cardiac CT in the most common clinical scenarios, standards of practice to optimize patient preparation and safety as well as image quality are described. Coronary CT angiography (CCTA) is the focus of Part I. In Part II, an overview of cardiac CT for non-coronary indications that include valvular and pericardial imaging, tumour and mass evaluation, pulmonary vein imaging, and imaging of congenital heart disease for diagnosis and treatment monitoring are discussed. The guidelines are intended to be relevant for community hospitals and large academic centres with established cardiac CT imaging programs.

CAR and CSTR Cardiac Computed Tomography (CT) Practice Guidelines: Part 1 Coronary CT Angiography (CCTA).

Imaging the heart is one of the most technically challenging applications of Computed Tomography (CT) due to the presence of cardiac motion limiting optimal visualization of small structures such as the coronary arteries. Electrocardiographic gating during CT data acquisition facilitates motion free imaging of the coronary arteries. Since publishing the first version of the Canadian Association of Radiologists (CAR) cardiac CT guidelines, many technological advances in CT hardware and software have emerged necessitating an update. The goal of these cardiac CT practice guidelines is to present an overview of the current evidence supporting the use of cardiac CT in various clinical scenarios and to outline standards of practice for patient safety and quality of care when establishing a cardiac CT program in Canada.

Prevalence and Functional Implication of Silent Coronary Artery Disease in Marathon Runners Over 40 Years of Age: The MATCH-40 Study.

BACKGROUND: Marathon participation is becoming increasingly popular among individuals ≥40 years of age. Little is known about the prevalence of subclinical coronary artery disease (CAD) and corresponding ischemia in this patient population. The study objectives are: (1) to characterize the prevalence of silent CAD in marathoners ≥ 40 years old using cardiac computed tomography angiography (CCT); and (2) if subclinical CAD was detected, to determine the functional significance of occult lesions by stress echocardiography (SE). METHODS: Marathoners aged ≥ 40 years who completed a full marathon between 2018 and 2019 were recruited to undergo a prospective CCT. Coronary artery stenosis was graded as zero, mild (1%-49%), moderate (50%-69%), or severe (> 70%). All study participants diagnosed with mild-to-severe atherosclerotic CAD on CCT further underwent functional imaging with exercise treadmill SE. RESULTS: A total of 65 individuals (53 ± 7 years, 65% males, 24 ± 3 kg/m2) underwent a prospective CCT within 12 months of marathon completion. Of the total study population, 13 participants (20%) were diagnosed with CAD, of whom 10 (77%) had mild disease, 1 (8%) had moderate disease, and 2 (15%) had severe disease by CCT. Despite the identification of subclinical CAD on CCT, none of the 13 patients had any evidence of inducible ischemia on SE. CONCLUSIONS: This is the first study to incorporate both CCT and SE in the evaluation of subclinical CAD in marathoners ≥40 years old. Although the overall prevalence of anatomic CAD was 20%, there was no evidence of functional ischemia in this highly competitive cohort.

CONTEXTE: Les marathons ont gagné en popularité auprès des individus âgés de 40 ans ou plus. On en sait toutefois peu sur la prévalence de la coronaropathie subclinique et de l'ischémie qui lui est associée dans cette population de patients. L'étude visait à 1) caractériser la prévalence de la coronaropathie silencieuse chez les marathoniens âgés de 40 ans ou plus à l'aide d'une angiographie cardiaque par tomodensitométrie (ACTDM) si une coronaropathie subclinique était détectée, à déterminer l'importance fonctionnelle des lésions occultes par une échocardiographie d'effort (EE). MÉTHODOLOGIE: Des marathoniens âgés de 40 ans ou plus ayant réalisé un marathon entre 2018 et 2019 ont été recrutés et soumis à une ACTDM prospective. Les sténoses des artères coronaires étaient classées selon une échelle allant de zéro, légère (1 à 49 %), modérée (50 à 69 %) à sévère (> 70 %). Tous les participants à l'étude ayant reçu un diagnostic de coronaropathie athéroscléreuse légère à sévère à la suite de l'ACTDM ont été soumis à une imagerie fonctionnelle avec EE sur tapis roulant. RÉSULTATS: Au total, 65 sujets (53 ± 7 ans, 65 % d'hommes, 24 ± 3 kg/m2) ont été soumis à une ACTDM prospective dans un délai de 12 mois à la suite de leur dernier marathon. Dans l'ensemble de la population à l'étude, 13 participants (20 %) ont reçu un diagnostic de coronaropathie; 10 (77 %) présentaient une maladie bénigne, 1 (8 %) présentait une maladie modérée et 2 (15 %) présentaient une maladie sévère selon l'ACTDM. Même si une coronaropathie subclinique a été diagnostiquée lors de l'ACTDM, aucun des 13 patients ne présentait de signe d'ischémie inductible à l'EE. CONCLUSIONS: Il s'agit de la première étude à utiliser l'ACTDM et l'EE pour évaluer la présence d'une coronaropathie chez des marathoniens âgés de 40 ou plus. Même si la prévalence globale de la coronaropathie anatomique était de 20 %, il n'y avait aucun signe d'ischémie fonctionnelle au sein de cette cohorte hautement compétitive.

Multimodality cardiac imaging of a double chambered right ventricle with intrapulmonary shunting: a case report.

BACKGROUND: Double chambered right ventricle (DCRV) is a relatively rare congenital heart disease, characterized by the abnormal division of the right ventricle into a high-pressure inlet and low-pressure outlet by anomalous muscle bundles. Extra-cardiac right-to-left shunts may present with clinical symptoms in adulthood and should be sought in patients with previous cavo-pulmonary shunt procedures. CASE PRESENTATION: We report a case of DCRV in a 29 year old Caucasian male presenting in adulthood with a right-to-left shunt secondary to venous collaterals, following cavopulmonary anastomosis for congenital pulmonary atresia and hypoplastic right ventricle. CONCLUSION: Multimodality cardiac imaging using echocardiography, cardiac CT, cardiac MRI and cardiac catheterization is often required for complete characterization of complex congenital heart anomalies in adulthood.

Multimodality imaging of aortic dimensions: comparison of transthoracic echocardiography with multidetector row computed tomography.

BACKGROUND: With recent advances in multimodality cardiac imaging, a number of methods exist for the noninvasive assessment of aortic disease. Although multidetector row computed tomography (MDCT) remains the gold standard for aortic measurements, there are a number of limitations including radiation and contrast-induced nephropathy. Transthoracic echocardiography (TTE) is an alternative to MDCT for providing accurate anatomic assessment of aortic root and ascending aorta dimensions. OBJECTIVES AND METHODS: To determine the accuracy of two-dimensional (2D) TTE for determining aortic measurements in comparison to MDCT, a retrospective study of individuals with varying aortic root and ascending aorta dimensions was performed. RESULTS: There were 116 patients (77 males, mean age 49 ± 12 years) in total. The maximum aortic diameters by 2D TTE were 26.1 ± 4.3 mm (annulus), 32.4 ± 5.6 mm (sinuses), 30.1 ± 5.9 mm (sinotubular [ST] junction), and 33.4 ± 7.3 mm (ascending aorta). The maximum aortic diameters by MDCT were 30.1 ± 4.1 mm (annulus), 35.8 ± 5.8 mm (sinuses), 33.2 ± 5.9 mm (ST junction), and 37.4 ± 7.6 mm (ascending aorta). There was good to excellent correlation between 2D TTE and MDCT at all four levels of the aorta (annulus: r = 0.84; sinuses: r = 0.93; ST junction: r = 0.93; ascending aorta: r = 0.88). There was a consistent underestimation of aortic measurements obtained by 2D TTE when compared to MDCT. CONCLUSION: 2DTTE is a feasible, accurate, and reproducible method for the noninvasive assessment of thoracic aortic diameters as compared to MDCT.

Multimodality imaging of anomalous pulmonary veins.

Partial anomalous pulmonary venous connection (PAPVC) is an extremely rare congenital condition where one or more of the pulmonary veins are connected to the venous circulation. Although initially suspected with unexplained right ventricular enlargement on transthoracic echocardiography (TTE), cardiac MRI is able to delineate the anatomical variant. We present a case of a 65-year-old male diagnosed with left sided PAPVC using multimodality cardiac imaging.

Utility of balanced steady-state free precession MR venography in the diagnosis of lower extremity deep venous thrombosis.

OBJECTIVE: The purpose of this study was to determine the sensitivity and specificity of balanced steady-state free precession MR venography in the diagnosis of lower extremity deep venous thrombosis. SUBJECTS AND METHODS: After undergoing lower extremity ultrasound because of suspicion of deep venous thrombosis, 64 patients were prospectively recruited to undergo balanced steady-state free precession MR venography with ultrasound as the reference standard. Ultrasound images were independently interpreted by two blinded ultrasound radiologists, and MR venograms were independently interpreted by two blinded MRI radiologists. The sensitivity, specificity, positive predictive value, and negative predictive value of MR venography were calculated for the diagnoses of all deep venous thrombosis, acute thrombi, and thrombosis of the popliteal, femoral, and common femoral veins individually. Proximal extent, thrombus age, ancillary findings, and interobserver agreement calculated with the Cohen kappa test were evaluated for ultrasound and MRI. The McNemar test was used to evaluate for statistical differences in diagnostic accuracy. RESULTS: MR venography had a sensitivity of 94.7%, specificity of 100%, positive predictive value of 100%, and negative predictive value of 97.7% for the diagnosis of all thrombi. For acute thrombi, the MR venography and ultrasound results were completely concordant. MR venography depicted greater proximal extent in five of 18 cases in which thrombosis was found. The MR venographic findings agreed completely with the ultrasound findings in determination of thrombus age. For both ultrasound and MR venography, interobserver agreement was 100% on a per-patient basis. No statistical difference was identified in the diagnostic performance of the two techniques. CONCLUSION: Balanced steady-state free precession MR venography is highly accurate in the diagnosis of lower extremity deep venous thrombosis.

Computed tomographic scan evaluation of pulmonary blastomycosis.

BACKGROUND: Blastomycosis is an uncommon granulomatous pulmonary and extrapulmonary infectious disease caused by the thermally dimorphic fungus Blastomyces dermatitidis. Diagnosis may be delayed or difficult because of varied presentation. The characteristics of blastomycosis on computed tomographic (CT) scan of the chest are not well characterized. METHODS: The images from 34 chest CT scans from patients with confirmed pulmonary blastomycosis were retrospectively reviewed. RESULTS: The most common CT findings were air bronchograms in 22 patients (65%), consolidation in 21 patients (62%), nodules (smaller than 3 cm) in 21 patients (62%) and lymph node enlargement (mediastinal and hilar nodes combined) in 12 patients (35%). Only four patients (12%) had a miliary pattern. CONCLUSIONS: A specific abnormality characteristic of pulmonary blastomycosis was not identified on CT scanning. The diagnosis can only be made in the context of a high index of clinical suspicion with histological or culture confirmation.