In acute situations such as non-ST-elevation infarction (NSTEMI) or relevant coronary artery disease (CAD) CMR does not yet play a key role due to its lengthy protocols. fSENC is a new CMR technique which may detect subclinical signs of myocardial damage by measuring myocardial strain (change in length/ unit length). A whole-heart coverage is generated in 6 heart-beats and the information obtained is converted into a colour-coded map. fSENC does not require major post-processing, long breath-holds and the administration of contrast agents/medication.
In this observational study fSENC is assessed in patients with chest pain and its capability to differentiate between an ischemic cause (NSTEMI, significant CAD), an underlying non-ischemic cardiac disease and non-cardiac chest pain. Additionally, we aim to identify the affected coronary arteries in the ischemic cohort. With fSENC it could be possible to successfully diagnose patients with suspected AMI in <1h after admission and also gain diagnostic information regarding the underlying pathology.
Patients with chest pain and an initial hscTnT level between 5pg/ml and 52 pg/ml are recruited. These patients then undergo an fSENC-CMR before 2nd hscTnT measurement. Additionally, a stress-induced fSENC-image is acquired (1-minute hyperventilation, followed by a single breath-hold). This breathing manoeuvre leads to an increase in oxygenation through vasodilation, therefore identifying ischemic areas. The fSENC analysis is later compared to the patient’s final diagnosis and therapy.
So far 50 patients have been analysed by fSENC in this observational study (26 female, aged 57 ± 18). fSENC correctly identified 7 patients suffering from NSTEMI or significant CAD and their affected coronary arteries. 42 other patients were safely ruled-out by fSENC which was consistent with the serial hscTnT results. In 11 patients fSENC was able to detect generalized impaired myocardial deformation, implying an underlying cardiac disease (hypertrophic cardiomyopathy, myocarditis). fSENC currently exhibits a sensitivity of 100% and specificity of 97,7% for correct rule-in/-out of an ischemic cause.
At this stage fSENC allows correct identification of patients suffering from myocardial infarction and their affected coronary arteries. Additionally, fSENC can safely rule-out patients with chest pain but no underlying ischemic cause. This novel technique is a rapid additional diagnostic tool which assesses myocardial function non-invasively without radiation exposure.