The Reliability of the Routine Chest Roentgenogram for Determination of Heart Size Based on Specific Ventricular Chamber Evaluation at Postmortem

Cardiothoracic ratio in postmortem computed tomography: reliability and threshold for the diagnosis of cardiomegaly

“…The cardiothoracic ratio (CTR) is frequently used to determine cardiomegaly in plain film chest radiography (CXR) [1][2][3]. Although it has also been criticized [4,5], it continues to be the routine way radiologists assess cardiomegaly. CTR is calculated by dividing the maximum transverse diameter of the heart with the maximum thoracic diameter [6]; values lower or higher than 0.5 are defined as ''normal heart size'' and ''cardiomegaly'' respectively [2,[7][8][9].…”

Cardiothoracic ratio (CTR) measured on post-mortem computed tomography (PMCT) – Pre- and post-ventilation

“…The Danzer method for measuring CTR has been criticised by some practitioners [3,16] and some alterations to this method have been suggested [3,4,16,17].…”

Evaluating Cardiomegaly by Radiological Cardiothoracic Ratio as Compared to Conventional Echocardiography

“…It is very important to adequately evaluate cardiac dimensions in the clinical setting. Therefore, assessing heart size by measuring the cardiothoracic ratio (CTR) still remains as a useful diagnostic tool in chest radiography evaluation [1][2][3]. Chest radiography is an auxiliary diagnostic method that is widely utilized since it is easy to perform, readily available, inexpensive, and allows assessment of heart size and its changes over time.…”

“…In other words the CTR is calculated by dividing the cardiac diameter by the thoracic diameter as measured on postero-anterior chest radiography. A value of 50% (0.5) is generally considered to indicate the upper limit of normal [2][3][4][5][6]. However, there are some cardiac with known left ventricular systolic dysfunction [24].…”

“…Accurate determination of the heart size including the diameter of each of the four chambers of the heart is a very important measurement which helps physicians in evaluating the etiology of cardiomegaly. Although, echocardiography is commonly superior to chest radiography in providing a better assessment of heart chamber size, it has been shown a satisfactory correlation between the CTR and the heart size found at autopsy studies [2]. Though heart chamber size can be determined by chest radiography, the diagnosis can be made more accurately by other more expensive imaging modalities.…”