Diagnostic accuracy of standard axial 64-slice chest CT compared to cardiac MRI for the detection of cardiomyopathies

Abstract

Objective: To assess the diagnostic accuracy of standard axial chest CT compared with cardiac MRI for cardiomyopathies. Methods: The standard axial 64-slice chest CTs of 49 patients with cardiomyopathies and 27 controls were blindly assessed for the presence of a cardiomyopathy by two independent readers. Qualitative and quantitative analysis included assessment of: (i) interatrial septal thickness, (ii) left atrial diameter, (iii) myocardial hypertrophy, thinning or fat, (iv) myocardial and papillary muscle calcification, (v) papillary muscle thickness, (vi) calcified coronary artery segments, (vii) left ventricular (LV) diameter, (viii) interventricular septal thickness and (ix) right ventricular diameters. Cardiac MRI was the gold standard. Results: There were 21 (42.9%) dilated, 16 (32.7%) hypertrophic, 8 (16.3%) ischaemic and 4 other (8.2%) (LV non-compaction 3 2, amyloid, idiopathic restrictive) patients with cardiomyopathies. An LV diameter of 47 mm, interventricular septal thickness of 14 mm and coronary artery/papillary muscle calcification on axial chest CT best distinguished dilated, hypertrophic and ischaemic cardiomyopathies from controls, respectively; kappa 5 0.45 (moderate interobserver agreement). The sensitivity (95% confidence interval), specificity, positiveand negative-predictive values (95% confidence interval) and diagnostic accuracy of chest CT in diagnosing cardiomyopathies were 68% (52-83), 100%, 100%, 66% (55-85) and 80%, respectively. Conclusion: Cardiomyopathies may be detected on standard chest CT with good sensitivity and high specificity. Advances in knowledge: It is useful to assess for an underlying cardiomyopathy on standard chest CT, especially in a patient with unexplained dyspnoea.

Diagnostic Accuracy of Sex-Specific Chest CT Measurements Compared With Cardiac MRI Findings in the Assessment of Cardiac Chamber Enlargement

“…LV transverse diameter has been previously investigated for the identification of LVE [4][5][6]. In two previous studies in which echo-cardiography was used as the reference standard [4,5], the investigators recommended LV transverse diameter thresholds of 55-56 mm for detection of LVE, which are similar to the threshold values identified in our study.…”

“…In two previous studies in which echo-cardiography was used as the reference standard [4,5], the investigators recommended LV transverse diameter thresholds of 55-56 mm for detection of LVE, which are similar to the threshold values identified in our study. A smaller study of LV transverse diameter on CT in a population of patients with cardiomyopathy and MRI as the reference standard [6] showed that an LV transverse diameter threshold of 47 mm had specificity of 100% and sensitivity of 47% for the diagnosis of dilated cardiomyopathy. In contrast to these studies in which LV transverse diameter was measured at the midventricular level, in our study the largest transverse diameter was measured at any level to maximize sensitivity.…”

“…For evaluation of LV enlargement (LVE), the maximum LV transverse diameter based on visual evaluation was measured perpendicular to the LV long-axis and interventricular septum, from LV septal to LV lateral endocardial blood pool border [4][5][6] (Fig. 2F).…”

“…In clinical practice, however, nongated chest CT is performed with much higher frequency. Only a few previous studies have evaluated measurements made at nongated chest CT for the detection of chamber enlargement in comparison with echocardiography [4,5,7] and cardiac MRI [6].…”

Toraks Bilgisayarlı Tomografi ve Koroner Bilgisayarlı Tomografi Anjiografide Atriyum ve Ventrikül Ölçümlerin Uyumluluğunun Değerlendirilmesi

“…As a result of our study, it was shown that the measurements of cardiac chambers in coronary CTA and non-ECG-gated, unreformed contrast-enhanced thoracic CT are perfectly compatible with each other. In the literature, there are several studies evaluating the dimensions of the heart chambers with coronary CTA (18)(19) or with non-ECG-gated thoracic CT (20) . However, in the English literature review, there was no study which was measured the diameter and area of the cardiac chambers in thoracic CT and coronary CTA and comparing them with each other.…”