Background The dilated phase of hypertrophic cardiomyopathy (HCM) has a poor prognosis. For correct recognition of such patients, we compared the findings in cardiac delayed enhancement (DE)-magnetic resonance imaging (MRI) between HCM and dilated cardiomyopathy (DCM) patients. Methods and Results Sixty-five patients (HCM 39, DCM 26) underwent gadolinium-DTPA–enhanced MRI. The HCM patients were divided into those with preserved (HCM-P, n=30) and those with impaired systolic function (HCM-I, n=9). DE-MRI demonstrated focal or diffuse DE at the left ventricular (LV) wall in 60% of HCM-P and 100% of HCM-I, but in only 12% of DCM. The DE distributed mainly septal to the anterior wall of LV, but the DE volume against whole LV muscle volume was much larger in HCM-I than in HCM-P and DCM (4.1 ± 6.1% in HCM-P, 14.6 ± 11.9% in HCM-I, and 0.8 ± 2.4% in DCM, means ± SD, P < .05). In HCM, there were weak but significant correlations between DE volume, and LV end-diastolic volume and LV end-systolic volume. In HCM-P, the percent of length shortening in the segments with DE was lower than that without DE. Conclusions The HCM patients had more DE than the DCM patients, and DE volume correlated to lower global and local LV function. DE-MRI may be useful to evaluate myocardial damage in HCM patients, and to differentiate the dilated phase of HCM from DCM.

In local and global disaster scenes, rapid recognition of victims’ breathing is vital. It is unclear whether the footage transmitted from small drones can enable medical providers to detect breathing. This study investigated the ability of small drones to evaluate breathing correctly after landing on victims’ bodies and hovering over them. We enrolled 46 medical workers in this prospective, randomized, crossover study. The participants were provided with envelopes, from which they were asked to pull four notes sequentially and follow the written instructions (“breathing” and “no breathing”). After they lied on the ground in the supine position, a drone was landed on their abdomen, subsequently hovering over them. Two evaluators were asked to determine whether the participant had followed the “breathing” or “no breathing” instruction based on the real-time footage transmitted from the drone camera. The same experiment was performed while the participant was in the prone position. If both evaluators were able to determine the participant’s breathing status correctly, the results were tagged as “correct.” All experiments were successfully performed. Breathing was correctly determined in all 46 participants (100%) when the drone was landed on the abdomen and in 19 participants when the drone hovered over them while they were in the supine position (p < 0.01). In the prone position, breathing was correctly determined in 44 participants when the drone was landed on the abdomen and in 10 participants when it was kept hovering over them (p < 0.01). Notably, breathing status was misinterpreted as “no breathing” in 8 out of 27 (29.6%) participants lying in the supine position and 13 out of 36 (36.1%) participants lying in the prone position when the drone was kept hovering over them. The landing points seemed wider laterally when the participants were in the supine position than when they were in the prone position. Breathing status was more reliably determined when a small drone was landed on an individual’s body than when it hovered over them.

Background: Conventional hands-on chest compression, in cardiopulmonary resuscitation, is often inadequate, especially when the rescuers are weak or have a small physique. Objectives: This study aimed to investigate the potential of leg-foot chest compression, with and without a footstool, during cardiopulmonary resuscitation. Methods and Results: We prospectively enrolled 21 medical workers competent in basic life support. They performed cardiopulmonary resuscitation on a manikin for 2 min using conventional hands-on compression (HO), leg-foot compression (LF), and leg-foot compression with a footstool (LF + FS). We analyzed the compression depths, changes in the rescuers’ vital signs, and the modified Borg scale scores after the trials. The compression depth did not differ between the cases using HO and LF. In the case of LF + FS, compression depths ⩾5 cm were more frequently observed (median, inter-quartile range: 93%, 81%–100%) than in HO (9%, 0%–57%, p < 0.01) and LF (28%, 11%–47%, p < 0.01). The increase in the heart rate or modified Borg scale scores, after the trials, did not differ between the HO and LF group; however, the values were the lowest in the case of LF + FS (49 ± 18 beats/min and 5 (4–7) in HO, 46 ± 18 and 6 (5–7) in LF, and 32 ± 11 and 2 (1–3) in LF + FS, respectively, p < 0.01). However, the increase in blood pressure, SpO₂, and respiratory rate were not different among each group. The increases in the heart rate and modified Borg scale scores negatively were correlated with the rescuers’ body size, in the case of HO and LF, but not LF + FS. Conclusion: LF can be used as an alternative to HO, when adequate HO is difficult. LF + FS could be used when rescuers are weak or have a small physique and when the victims are bigger than the rescuers.

Background: ECG interpretation is sometimes difficult due to baseline fluctuations and electrode detachments when placed on the subjects’ front side, leading to misinterpretation of the rhythms and phases of the cardiac cycle. We aimed to compare the differences in the wave amplitudes and respiratory variations between conventional ECG electrode positioning on the front side of patients and an alternative position on the backs of patients. Methods: Echocardiography was performed in 85 patients lying in the left lateral position. We attached the red electrode to the right clavicle, the yellow to the left clavicle, and the green to the left lateral abdomen on the front side of the patients; on the back, we attached the electrode to the right clavicle, the right upper posterior iliac spine, and the left upper posterior iliac spine. Results: The ECG monitor amplitudes were greater on the front side compared to the back side, but the BF-breath values were smaller on the back side (6.0 pixels) compared to the front side (10.5 pixels, p<0.05). The P wave amplitude divided by the BF-breath on the back side was greater than that seen on the front side (2.8 vs. 1.8, p<0.05), whereas the QRS amplitude divided by the BF-breath was 15.0 and 16.3, respectively (p=ns). Conclusion: As an alternative to front-side ECG monitoring, electrodes placed on the back can help avoid misinterpretation of the ECG rhythms and the phases of the cardiac cycle due to respiration during echocardiography.