Real-time CMR Fourier Analysis for Temporospatial Characterization of Ventricular Wall Motion in Health and Disease

Background Cardiovascular magnetic resonance (CMR) has been largely dependent on retrospective cine for image acquisition. Real-time imaging, although inferior in image quality to retrospective cine, is advantageous in examining temporospatial behaviors of cardiac motion over a series of sequential cardiac cycles. The presented work is a proof-of-concept of assessing cardiac function quantitatively with novel temporospatial indices in real-time CMR. Methods Fourier analysis was introduced for temporospatial characterization of real-time CMR signals arising from ventricular wall motion. Two quantitative indices, temporal periodicity and spatial coherence, were provided for function assessment in the left ventricle (LV) and right ventricle (RV). We prospectively investigated these temporospatial indices in a CMR study with healthy volunteers and heart failure (HF) patients. Results Real-time images were collected and analyzed in 12 healthy volunteers during exercise and at rest, and also in 12 HF patients at rest. The statistics indicated that the healthy volunteers presented an increase of temporal periodicity due to ventricular response to exercise (resting-state 0.24 ± 0.037 vs. exercising-state 0.31 ± 0.040 in LV; resting-state 0.18 ± 0.030 vs. exercising-state 0.25 ± 0.038 in RV; P < 0.001 for both). The HF patients gave lower temporal periodicity (0.14 ± 0.021 for LV; 0.10 ± 0.014 for RV; P < 0.001 for both) than that in the healthy volunteers. The spatial coherence of LV and RV wall motion was also lower in the HF patients than that in the healthy volunteers (0.38 ± 0.040 vs 0.52 ± 0.039 for LV; 0.35 ± 0.035 vs. 0.50 ± 0.036 for RV; P < 0.001 for both). Both temporal periodicity and spatial coherence were found to be correlated to end-systolic volume (ESV) and ejection-fraction (EF) (R > 0.6, P < 0.001). However, the HF patients and healthy volunteers were well differentiated in the scatter plots of spatial coherence and temporal periodicity while they were mixed in those of ESV and EF. Conclusions Real-time CMR Fourier analysis enables a new approach to quantitative assessment of cardiac function with temporal periodicity and spatial coherence. The temporospatial characterization of real-time CMR images has the potential for intricate analysis of ventricular wall motion beyond conventional methods.

Accidental self-injection of intravenous epinephrine by healthcare personnel

Epinephrine is a key drug used in resuscitation, including advanced life support situations. A 28-year-old nurse inadvertently injected herself with an ampule of epinephrine and was brought to the emergency department. The injection caused a drop in blood pressure, pulmonary edema, and cardiac enzyme elevation. Upon further evaluation, echocardiography revealed left ventricular wall motion abnormality with reduced ejection fraction. The patient was diagnosed with stress-induced cardiomyopathy (SCMP) and was treated appropriately. After a short stay in the intensive care unit as the vital signs were affected, the patient was transferred to the ward on the second day of hospitalization and was well enough to be discharged on the fifth day. The treatment of SCMP induced by epinephrine is largely conservative with a symptomatic approach. In most cases, the outcome is favorable. Inappropriate drug use, accidental or otherwise, can pose a great risk. More stringent caution should be practiced by medical staff in handling medication to prevent serious medication-related accidents.

Left ventricular wall motion abnormality is associated with cryptogenic stroke

Background Left ventricular wall motion abnormality (LVWMA) unrelated to known cardiac risk factors is an uncertain risk for stroke. Aims We evaluated whether LVWMA was associated with cryptogenic stroke. Methods This retrospective, observational study included 4316 acute ischemic stroke patients, and the association between cryptogenic stroke and LVWMA was examined in comparison with other stroke subtypes. Results The prevalence of LVWMA was 10.0% in the study population. In a fully adjusted, binary logistic regression, LVWMA was independently associated with cryptogenic stroke compared with stroke from large artery atherosclerosis (odds ratio = 1.627, 95% confidence interval = 1.129–2.345), small vessel occlusion (odds ratio = 1.948, 95% confidence interval = 1.261–3.010), or other causes (odds ratio = 4.950, 95% confidence interval = 1.145–21.412). Meanwhile, the association of LVWMA with cryptogenic stroke was similar to the associations of LVWMA with cardioembolic stroke (odds ratio = 0.758, 95% confidence interval = 0.525–1.094) and stroke with two or more causes (odds ratio = 0.992, 95% confidence interval = 0.609–1.615). In multinomial regression, LVWMA had the strongest association with cardioembolic stroke, followed by cryptogenic stroke and stroke from two or more causes. The strength of the associations with LVWMA then decreased sequentially in patients with large artery atherosclerosis, small vessel occlusion, and other causes. Conclusions The association of LVWMA with cryptogenic stroke was comparable to that of LVWMA with cardioembolic stroke but stronger than that of LVWMA with non-cardioembolic stroke. LVWMA unrelated to known cardiac risk factors could be considered an independent risk factor for cryptogenic stroke.

Hazards of ventricular pre-excitation to left ventricular systolic function and ventricular wall motion in children: analysis of 25 cases

AimThe aim was to attach importance to the hazards of ventricular pre-excitation on left ventricular systolic function and size.MethodWe analysed the clinical, electrophysiological, and echocardiographic characteristics of the 25 cases with abnormal ventricular wall motion, left ventricular systolic dysfunction, or dilation with co-existing right-sided overt accessary pathways before and after ablation or medication during March 2011 and June 2017. Moreover, we compared the therapy effect between patients with ventricular pre-excitation-induced dilated cardiomyopathy and idiopathic dilated cardiomyopathy without ventricular pre-excitation.ResultAbnormal ventricular wall motion was demonstrated using M-mode echocardiography in 23 cases. The basal segments of the interventricular septum became thin and moved similarly to an aneurysm with typical bulging during end-systole, which was observed in 16 cases. Dilated cardiomyopathy was diagnosed in 14 cases. A total of 23 patients underwent successful ablations and received medications, and the other two patients received only oral medications because of young age. The prognosis of pre-excitation-induced dilated cardiomyopathy is better than idiopathic dilated cardiomyopathy. All the cases with abnormal ventricular wall motion demonstrated recovery of normal left ventricular ejection fraction and decreased left ventricular end-diastolic diameter through ablation.ConclusionVentricular pre-excitation caused by right-sided accessory pathways may result in abnormal ventricular wall motion, left ventricular systolic dysfunction, dilation, and even dilated cardiomyopathy. In some cases with dilated cardiomyopathy, ventricular pre-excitation may not be the cause of disease but a harmful factor which hampered the recovering of left ventricular systolic function. These conditions are indications for ablation with good prognosis.