TY - JOUR
T1 - Post-mortem cardiac magnetic resonance parameters in normal and diseased conditions
AU - Femia, Giuseppe
AU - Langlois, Neil
AU - Raleigh, Jim
AU - Perumal, Sunthara Rajan
AU - Semsarian, Christopher
AU - Puranik, Rajesh
PY - 2021
Y1 - 2021
N2 - Background: Post-mortem cardiac magnetic resonance (CMR) is a non-invasive alternative to conventional autopsy. At present, diagnostic guidelines for cardiovascular conditions such as hypertrophic cardiomyopathy have not been established. We correlated post-mortem CMR images to definite conventional autopsy findings and hypothesed that elevated T2-weighted signal intensity and RV to LV area ratios can identify myocardial infarction and pulmonary emboli respectively. Methods: For this unblinded pilot sub-study, we selected cases from the original blinded study that compared post-mortem imaging to conventional autopsy in patients referred for coronial investigation between October 2014 to November 2016. Three groups of scans were selected based on the cause of death identified by conventional autopsy: non-cardiovascular causes of death with no structural cardiac abnormality i.e., control cases, acute/subacute myocardial infarction and pulmonary emboli. Left ventricular (LV) wall thickness, LV myocardial signal intensity and ventricular cavity areas were measured. Results: Fifty-six scans were selected [39 (69.6%) males]: 37 (66.1%) controls, eight (14.3%) acute/ subacute myocardial infarction and eleven (19.6%) pulmonary emboli. The median age was 61 years [Interquartile range (IQR) 50–73] and the median time from death to imaging and autopsy was 2 days (IQR 2–3) and 3 days (IQR 3–4). The septal and lateral walls were thicker {15 mm [13–17] and 15 mm [14–18]} on post-mortem CMR than published ante-mortem measurements. Areas of acute/subacute myocardial infarction had significantly higher T2-weighted signal intensity (normalised to skeletal muscle) compared to normal myocardium in those who died from other causes {2.5 [2.3–3.0.] vs. 1.9 [1.8–2.3]; P<0.001}. In cases with pulmonary emboli, there was definite RV enlargement with a larger indexed RV to LV area ratio compared to those who died from other causes {2.9 [2.5–3.0] vs. 1.8 [1.5–2.0]; P<0.001}. Conclusions: We present potential post-mortem CMR parameters to identify important cardiovascular abnormalities that may be beneficial when conventional autopsy cannot be performed. In patients without cardiovascular disease, LV wall thickness was found to be unreliable in diagnosing hypertrophic cardiomyopathy without histological and/or genetic testing. Elevated T2 signal intensity and RV to LV area ratios may be useful markers for acute/subacute myocardial infarction and pulmonary emboli. Larger studies will be necessary to define cut-offs.
AB - Background: Post-mortem cardiac magnetic resonance (CMR) is a non-invasive alternative to conventional autopsy. At present, diagnostic guidelines for cardiovascular conditions such as hypertrophic cardiomyopathy have not been established. We correlated post-mortem CMR images to definite conventional autopsy findings and hypothesed that elevated T2-weighted signal intensity and RV to LV area ratios can identify myocardial infarction and pulmonary emboli respectively. Methods: For this unblinded pilot sub-study, we selected cases from the original blinded study that compared post-mortem imaging to conventional autopsy in patients referred for coronial investigation between October 2014 to November 2016. Three groups of scans were selected based on the cause of death identified by conventional autopsy: non-cardiovascular causes of death with no structural cardiac abnormality i.e., control cases, acute/subacute myocardial infarction and pulmonary emboli. Left ventricular (LV) wall thickness, LV myocardial signal intensity and ventricular cavity areas were measured. Results: Fifty-six scans were selected [39 (69.6%) males]: 37 (66.1%) controls, eight (14.3%) acute/ subacute myocardial infarction and eleven (19.6%) pulmonary emboli. The median age was 61 years [Interquartile range (IQR) 50–73] and the median time from death to imaging and autopsy was 2 days (IQR 2–3) and 3 days (IQR 3–4). The septal and lateral walls were thicker {15 mm [13–17] and 15 mm [14–18]} on post-mortem CMR than published ante-mortem measurements. Areas of acute/subacute myocardial infarction had significantly higher T2-weighted signal intensity (normalised to skeletal muscle) compared to normal myocardium in those who died from other causes {2.5 [2.3–3.0.] vs. 1.9 [1.8–2.3]; P<0.001}. In cases with pulmonary emboli, there was definite RV enlargement with a larger indexed RV to LV area ratio compared to those who died from other causes {2.9 [2.5–3.0] vs. 1.8 [1.5–2.0]; P<0.001}. Conclusions: We present potential post-mortem CMR parameters to identify important cardiovascular abnormalities that may be beneficial when conventional autopsy cannot be performed. In patients without cardiovascular disease, LV wall thickness was found to be unreliable in diagnosing hypertrophic cardiomyopathy without histological and/or genetic testing. Elevated T2 signal intensity and RV to LV area ratios may be useful markers for acute/subacute myocardial infarction and pulmonary emboli. Larger studies will be necessary to define cut-offs.
UR - https://hdl.handle.net/1959.7/uws:66469
U2 - 10.21037/cdt-20-948
DO - 10.21037/cdt-20-948
M3 - Article
SN - 2223-3652
VL - 11
SP - 373
EP - 382
JO - Cardiovascular Diagnosis and Therapy
JF - Cardiovascular Diagnosis and Therapy
IS - 2
ER -