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We previously found the frequency distribution of the left ventricular (LV) effective afterload elastance ([E.sub.a]) of arrhythmic beats to be nonnormal or non-Gaussian in contrast to the normal distribution of the LV end-systolic elastance ([E.sub.max]) in canine in situ LVs during electrically induced atrial fibrillation (AF). These two mechanical variables determine the total mechanical energy [systolic pressure-volume area (PVA)] generated by LV contraction when the LV end-diastolic volume is given on a per-beat basis. PVA and [E.sub.max] are the two key determinants of the LV [O.sub.2] consumption per beat. In the present study, we analyzed the frequency distribution of PVA during AF by its [chi square], significance level, skewness, and kurtosis and compared them with those of other major cardiodynamic variables including [E.sub.a] and [E.sub.max]. We assumed the volume intercept ([V.sub.o]) of the end-systolic pressure-volume relation needed for [E.sub.max] determination to be stable during arrhythmia. We found that PVA distributed much more normally than [E.sub.a] and slightly more so than [E.sub.max] during AF. We compared the [chi square], significance level, skewness, and kurtosis of all the complex terms of the PVA formula. We found that the complexity of the PVA formula attenuated the effect of the considerably nonnormal distribution of [E.sub.a] on the distribution of PVA along the central limit theorem. We conclude that mean (SD) of PVA can reliably characterize the distribution of PVA of arrhythmic beats during AF, at least in canine hearts. end-systolic elastance; effective afterload elastance; frequency distribution; normality

A comprehensive equation defining the force of restitution and potentiation in terms of two preceding beat intervals was used in a computer simulation approximating the contractilities of irregular arrhythmic beats. The relationship among the different parameters under investigation was similar to the results of an experimental procedure previously undertaken. This suggests that mechanical restitution and potentiation are responsible for the variable contractilities observed in arrhythmia.

Objectives: The aim of this study was to measure the diaphragm volume using three-dimensional computed tomography (3D-CT) and verify its validity., Design: This was a retrospective study of existing samples., Methods: Participants comprised five male patients, aged 65-70 years, who underwent preoperative chest CT (with a slice thickness of 0.5 mm) before coronary artery bypass surgery. The diaphragm was selectively extracted using a workstation to reconstruct a stereoscopic image, and the total muscle volume was measured. To confirm the accuracy and reproducibility of diaphragm muscle volume measurements on CT, all cases were measured three times by two observers, and intraclass correlation coefficients (ICCs) and interobserver correlations were determined., Results: Observers #1 and #2 reported an average diaphragm volume of 256.7±33 cm 3 and 259.3±36 cm 3 , respectively. The ICC analyses yielded Cronbach's alphas of 0.992 and 0.981 from both observers, and the interobserver correlation was 0.991. The ICC of a single measurement and the average measurement was 0.984 (95% confidence interval: 0.998-0.884) and 0.992 (95% confidence interval: 0.999-0.939), respectively., Conclusions: To our knowledge, this study is the first to standardize the method for measuring the total diaphragm volume and examine the reproducibility and validity of the new method. The diaphragm could be selectively extracted and reconstructed. Measurement of the total diaphragm muscle volume using a workstation to reconstruct a stereoscopic image is feasible and highly reproducible. This technique can be reliably employed to evaluate diaphragm volume, thickness, and morphology., Competing Interests: The authors declare that there are no conflicts of interest., (© 2022 The Juntendo Medical Society.)

A 49-year-old female patient with a symptom of dysphagia underwent endoscopic ultrasonography (EUS) of the upper gastrointestinal tract, which incidentally revealed a tumor compressing the esophagus from outside. Transthoracic echocardiography performed after EUS showed a giant tumor in the left atrium. The tumor, measuring 75×68×43 mm, weighing 105 g was successfully removed, and pathologically diagnosed as myxoma. Her symptom disappeared completely. When performing clinical studies, it is important to pay every attention not to miss any abnormal findings beyond the scope of targeted areas. We also mentioned an ambiguity of the term," giant" regarding the size and weight of myxoma.

Background: Rapid mobilization and rehabilitation after CABG has a potential benefit of reducing both costs and pulmonary complications (such as atelectasis and pulmonary embolism). Moreover, it improves the patient's emotional recovery. We performed fast-track cardiac anesthesia aiming toward early rehabilitation., Methods: Patients undergoing CABG surgery (total, 140: on-pump 97, off-pump 43) were studied. Anesthesia was induced and maintained with low doses of fentanyl and propofol. The outcome of our perioperative management was retrospectively reviewed on the basis of clinical records., Results: The duration of the operation was 282 +/- 71 min. Anesthesia time was 353 +/- 72 min. The doses of fentanyl and propofol were 11.9 +/- 2.9 microg x kg(-1) and 16.8 +/- 5.4 mg x kg(-1), respectively. Time to extubation was 213 +/- 676 min, and the percentage of cases extubated within 3 h was 82%. As for outcome, the percentages of first oral intake, first rising from bed, and first gait performed on postoperative day 1 were 92%, 78%, 61%, respectively. The period of ICU stay was 2 days (median value). There were no perioperative complications related to early rehabilitation., Conclusions: We can safely manage fast-track cardiac anesthesia and perioperative management aiming toward early rehabilitation after CABG surgery.