ABSTRACT
@#The cardiac conduction system (CCS) is a set of specialized myocardial pathways that spontaneously generate and conduct impulses transmitting throughout the heart, and causing the coordinated contractions of all parts of the heart. A comprehensive understanding of the anatomical characteristics of the CCS in the heart is the basis of studying cardiac electrophysiology and treating conduction-related diseases. It is also the key of avoiding damage to the CCS during open heart surgery. How to identify and locate the CCS has always been a hot topic in researches. Here, we review the histological imaging methods of the CCS and the specific molecular markers, as well as the exploration for localization and visualization of the CCS. We especially put emphasis on the clinical application prospects and the future development directions of non-destructive imaging technology and real-time localization methods of the CCS that have emerged in recent years.
ABSTRACT
@#Although extracorporeal membrane oxygenation (ECMO) has been in existence since the 1970s as a means of supporting respiratory or cardiac function, early application of this technology was plagued by high complication rates. Peripheral veno-arterial extracorporeal membrane oxygenation (V-A ECMO) causes higher left ventricular end-diastolic pressure, pulmonary edema, left ventricular distention, ventricular arrhythmia, low coronary perfusion, myocardial ischemia, substantial thrombus formation within left ventricule cavity and even multiple organ dysfunction. Mechanical left ventricular decompression is required to treat these related complications. In this article, we reviewed the problems associated with left ventricular decompression supported by peripheral V-A ECMO in patients with cardiogenic shock.
ABSTRACT
@#Objective To explore the mechanism of volume-related mitral regurgitation (MR) from the anatomy of mitral valve. Methods A total of 32 patients with ventricular septal defect (VSD) combined MR meeting inclusion criteria in West China Hospital from September 2018 to November 2019 were enrolled in this study. The direction relative to the cardiac axis: the deviation of the MR bundle along the left atrial wall was eccentric, otherwises it was central. There were 23 patients of VSD and eccentric MR (EMR, a VSD-EMR group), including 10 males and 13 females aged 21 (10, 56) months, and 9 patients of VSD and central MR (CMR, a VSD-CMR group), including 4 males and 5 females aged 26 (12, 87) months. Besides, 9 healthy children were enrolled in a control group, including 4 males and 5 females aged 49 (15, 72) months. All patients underwent transthoracic echocardiography (TTE) examination at 2 weeks before surgery and 6 months after surgery, respectively, The MR degree, end-diastolic volume (EDV), end-systolic volume (ESV), stroke volume (SV), ejection fraction (EF), antero-posterior diameter (AP), annulus circumference (AC), commissural diameter (CD) were assessed. Results Before operation, EDV, ESV, SV, AP, AC and CD in the VSD-EMR and VSD-CMR groups were significantly larger or longer than those in the control group (P<0.05); after operation, EDV, ESV, SV, AP and CD decreased compared with those before operation (P<0.05), but there was no significant difference compared with the control group (P>0.05). Compared with the control group, AC was slightly decreased (P<0.05). There was no significant difference in EF between and within groups before and after operation (P>0.05). The improvement rate of MR was 78.9%(15/19) in the VSD-EMR group and 100.0% (9/9) in the VSD-CMR group. Conclusion After unloading of volume, the valve structure is back to normal except AC. The improvement rate of MR in the VSD-EMR group is lower than that in the VSD-CMR group, which may indicate that the mechanism of VSD-EMR is more complicated.