A Hakeem, F Shaheen, H Shafi, T Gojwari, S Rasool
A Hakeem, F Shaheen, H Shafi, T Gojwari, S Rasool. Spontaneous coronary artery dissection: Imaging with 64 Slice CT Scan. The Internet Journal of Radiology. 2009 Volume 12 Number 1.
Spontaneous coronary artery dissection is being increasingly detected with more liberal use of diagnostic modalities like coronary catheterization. The unique demographic features of this cohort of patients like younger age and lack of traditional risk factorsmake prompt diagnosis vital part of the management. Use of latest a non-invasive imaging modality like 64 slice CT in the diagnosis of these patients together withincreasingly successful treatment with drugs shall go in along way in ensuringconservative management of most these patients.
Spontaneous coronary artery dissection usually affects young people
predominantly pre-menopausal females with absence of coronary risk factors like,
smoking, increased cholesterol, hypertention etc. One subset of patients of SCAD occurs
during pregnancy or within few weeks of delivery whereas the other subset constitutes
patients both male and female with majority being females and usually without any
traditional risk factors of coronary artery disease.
A 48 year old premonopausal female with no evident risk factors of ischemic heart
disease presented with acute chest pain. ECG revealed acute anterior wall infarct without
any significant heamodynamic abnormality. Patient was thrombolysed and put on
conservative therapy including antiplatelet drugs, clopidogril and beta blockers. In view
of the clinical features, acute coronary syndrome was suspected. As the patient’s
condition was improving she was reluctant to undergo coronary catheterization. In view
of improving conditions, patient was offered CT coronary angiography. CT angiography
was conducted using 64 slice MDCT (Somatom Sensation 64, Siemens, Germany) using
70 ml of non-ionic contrast with 30 ml of saline chase and retrospective ECG gating. 3D
rendering showed focal thickening of LM (Fig1).
Multiplanar reconstructions revealed spiral dissection of left main coronary artery extending into the left anterior descending coronary artery (Fig 2&3).
Multiphase reconstruction with functional study
of left ventricle showed hypo kinetic anterior wall.
No intramural thrombus formation was seen. No congenital anomaly of coronary origin
was revealed. The patient is asymptomatic on six months follow-up.
Spontaneous coronary artery dissection is rare cause of acute coronary syndrome and
presents usually in patients without any risk factors associated with coronary artery
disease. One subset of patients is pregnancy related wherein SCAD occurs during
pregnancy or within few weeks postpartum. (1).Other subset of patients includes both
female and male patients with predominance of the female patients again without any risk
factors. The patients usually present with acute coronary syndrome of MI or angina. In a
series of 5400 cases of suspected IHD undergoing coronary angiography ,primary SCAD
was found in 23 cases,12 in RCA,10 in LAD and one in LCX.(2). In another series (3),
10 patients were detected in three year period, most of whom were premonopausal
women. All of these patients survived on follow-up with full recovery in 7 patients on
medical therapy. Thayer JO et al (4) reported 85 cases of SCAD in a review of literature
till 1987. Another series of 5054 angiograms revealed 5 case of coronary dissection all of
whom were women of premonopausal age. (5).Most of these patients were treated
conservatively with drugs and were found to be asymptomatic on follow-up at 22 months
to 3.8 years. In two large series (2&6), most of patients with SCAD had single vessel
involvement of RCA followed by LAD. Few patients needed acute intervention like
PTCA(2&7) and further smaller number needed CABG. Most of the case reports of
spontaneous coronary artery dissection have been found on conventional
angiography.There are few reports of diagnosis of coronary artery dissection by MDCT
using 64 slice CT scan (8)and one report of diagnosis by Intravascular Ultrsonography(9).