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Background Severe aortic stenosis (AS) is increasing in the aging society and is a serious condition for anesthetic management. However, approximately one-third of patients with severe AS are asymptomatic. Echocardiography is the most reliable method to detect AS, but it takes time and is costly. Methods Data were obtained retrospectively from patients who underwent surgery and preoperative transthoracic echocardiography (TTE). LVH on ECG was determined by voltage criteria (Sv 1 + Rv 5 or 6 ≥3.5 mV) and/or the strain pattern in V 5 and V 6 . Severe AS was defined as a mean transaortic pressure gradient ≥40 mmHg or aortic valve area ≤1.0 cm 2 by TTE. Results Data for 470 patients aged 28–94 years old were obtained. One hundred and twenty-six patients had severe AS. LVH on ECG by voltage criteria alone was detected in 182 patients, LVH by strain pattern alone was detected in 80 patients and LVH by both was detected in 55 patients. Multivariable logistic analysis revealed that LVH by the strain pattern or voltage criteria, diabetes mellitus, and age were significantly associated with severe AS. The AUC for the ROC curve for LVH by voltage criteria alone was 0.675 and the cut-off value was 3.84 mm V, and the AUC for the ROC for age was 0.675 and the cut-off value was 74 years old. Conclusion Our study suggests that patients who are 74 years old or over with LVH on ECG, especially those with DM, should undergo preoperative TTE in order to detect severe AS.

Background In a patient with very long-chain acyl-Coenzyme A dehydrogenase (VLCAD) deficiency, metabolism of fatty acids is impaired and a supply of alternative energy is limited when glucose level is insufficient on starvation. Case presentation A 37-year-old woman with VLCAD deficiency was diagnosed with an ovarian cyst and was scheduled for laparoscopic ovarian cystectomy. Glucose was administered intravenously with the start of fasting. Anesthesia was induced with remifentanil, midazolam, and thiamylal, maintained with desflurane and remifentanil. Body temperature was maintained at 36.2–36.7 °C. During anesthesia, hypoglycemia did not occur, creatine kinase levels were in the normal range, and myoglobinuria was not detected. No shivering was observed after extubation. Conclusions Glucose was administered to avoid perioperative hypoglycemia. Body temperature was controlled to avoid shivering, which would otherwise increase skeletal muscle energy needs. Blood creatine kinase did not increase, and myoglobinuria was not detected; thus, rhabdomyolysis was unlikely to develop.

What is known and objective Propofol is the most commonly used intravenous anaesthetic worldwide and is considered to be safe for all ages. However, there have been some reports that propofol induces severe atrioventricular (AV) blocks in humans and some studies demonstrated that propofol suppressed the cardiac conduction system in animals. A precise mechanism by which the block is induced has not been elucidated yet in humans. The objective of this study was to investigate the effects of propofol on the cardiac conduction system and the cardiac autonomic nervous balance in children. Methods We enrolled 23 paediatric patients (age: 6‐15 years; males: 16, females: 7) who were scheduled to undergo radiofrequency catheter ablation (RFCA) under general anaesthesia. Anaesthesia was induced with 2 mg/kg propofol and 0.5 µg/kg/min remifentanil, and tracheal intubation was performed with the aid of 1 mg/kg rocuronium. Anaesthesia was maintained with 5‐7 mg/kg/h propofol and 0.2 µg/kg/min remifentanil during the RFCA. After the completion of the RFCA, anaesthesia was further maintained with 5 mg/kg/h propofol and 0.2 µg/kg/min remifentanil for at least 10 min (LC: low propofol concentration state), followed by the injection of 2 mg/kg propofol and the infusion of 10 mg/kg/h propofol for 10 min (HC: high propofol concentration state). The sinus node recovery time (SNRT), sinoatrial conduction time (SACT), atrial‐His (AH) interval and the His‐ventricular (HV) interval were measured at the end of both the LC and HC. Cardiac autonomic regulation was simultaneously assessed based on heart rate variability. Results and discussion Propofol significantly suppressed intrinsic cardiac HV conduction, but did not affect the SNRT, SACT or the AH interval. As HV blocks, which occur below the His bundle, are often life‐threatening, the HV conduction delay may be a cause of severe AV blocks induced by propofol. Propofol directly suppressed parasympathetic nerve activity, and sympathetic nerve activity was also suppressed. What is new and conclusion These results indicate that propofol suppresses the HV conduction and might help to elucidate the mechanism by which propofol causes lethal AV blocks.

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