Clinical diagnosis
Case 181
【Progress】
He was suspected to have coronary disease. Unfortunately, we did not have expert physicians of cardiologist and cardiac surgeon. Then, he was transported to the hospital where he was able to get the service of investigating cardiac diseases.
【Discussion】
Pericardium consists of external fibrous membrane and internal serous membrane (1). There is usually fluid of less than 50ml in pericardial space of a normal person (1, 2). It functions to protect heart and to facilitate cardiac motion by reducing its friction. Pericardium covers great vessels as well. Namely, it covers heart plus 2 or 3 cm of the base of great vessels before bifurcation, forming sinus and recess (2-7).
Great vessels mean arterial tubes and venous tubes. Ascending aorta and pulmonary artery belong to arterial tubes. Pulmonary veins, superior vena cava and inferior vena cava belong to venous tubes. Each great vessel has the pericardial fluid surrounding its origin.
In the pericardium space, there are two sinuses: transvers sinus and oblique sinus (1, 2). Transvers sinus exists at behind the base of ascending aorta and pulmonary artery and at anterior to superior vena cava in frontal view. It exists at between right and left pulmonary arteries in axial view and extends around the base of arterial tubes, forming recess: inferior and superior ascending aorta recess, pulmonary artery recess. Oblique sinus exists at between right and left pulmonary veins in an axial view and extends around the base of venous tubes: pulmonary vein recess, IVC recess and post cava (SVC) recess.
Recess is further divided into small spaces depending on the sites surrounding the great vessel (2-7). For example, ascending aorta recess is divided into anterior superior aortic recess, posterior superior aortic recess, right superior aortic recess. Posterior superior aortic recess is often encountered on usual thoracic CT. These sinus and recess appear in case of peri-cardiac effusion. For diagnostic radiologists, it is imperative to differentiate these recess and sinus from lymphadenopathy, bronchogenic cyst and peri-cardiac cyst.
In our case, thoracic CT was taken in order to check aortic dissection. It showed small spaces along with ascending aorta. The CT values of these spaces were below 10HU, indicating not hematoma but water density. As a result, the small spaces surrounding ascending aorta were posterior superior aortic recess, anterior superior aortic recess and right superior aortic recess. Laboratory test revealed that the value of Troponin which elevate in case of myocardial infarction was normal, while BNP which elevate in case of cardiac failure was high indicative of mild cardiac stress burden. Thoracic CT was useful to check atheromatous change of coronary artery and to deny aortic intimal dissection.
【Summary】
We present a sixty six-year-old male presented in our hospital for thoracic pain, back pain and palpitation. Thoracic CT showed small spaces along with base of ascending aorta, mimicking intimal dissection of ascending aorta. CT values of these spaces indicate less than 10 HU. As a result, these small spaces were posterior superior aortic recess, anterior superior aortic recess and right superior aortic recess. It is in borne in mind that pericardium has transvers sinus and oblique sinus. Each sinus has several recesses surrounding the base of great vessels. Transvers sinus exists at between right and left pulmonary arteries and extends around the base of arterial tubes, forming recess. Oblique sinus exists at between right and left pulmonary veins in an axial view and extends around the base of venous tubes.
【References】
1.Choe YH, et al. The anatomy of the pericardial space: a study in cadavers and patients. AJR 1987; 149:693 –697
2.Truong MT, et al. Anatomy of Pericardial Recesses on Multidetector CT: Implications for Oncologic Imaging. American Journal of Roentgenology. 2003;181: 1109-1113.
3.Groell R, Schaffler GJ, Rienmueller R. Pericardial sinuses and recesses: findings at electrocardiographically triggered electron-beam CT. Radiology 1999; 212:69 –73
4.Levy-Ravetch M, et al. CT of the pericardial recesses. AJR 1985; 144:707 –71
5.Vesely TM, et al. Cross-sectional anatomy of the pericardial sinuses, recesses, and adjacent structures. Surg Radiol Anat 1986; 8:221 –227
6.Choi YW, et al. The “high-riding” superior pericardial recess: CT findings. AJR 2000; 175:1025 –1028
7.Glazer HS, et al. Pitfalls in CT recognition of mediastinal lymphadenopathy. AJR 1985; 144:267 –274
2020.2.19