Novel Use of the Perceval Valve for Prosthetic Aortic Valve Endocarditis Requiring Root Replacement

The surgical management of aortic valve endocarditis can be challenging. Infection with abscess formation can destroy the root and annulus, making it difficult to anchor a valve conduit. In this article, we present a novel and efficient strategy for proximal aortic reconstruction. We used a Dacron tube graft and anchored it proximally with a running suture line deep in the left ventricular outflow tract. The coronary buttons were attached, and a Perceval valve was then deployed inside the neo-root to create a bio-Bentall.

Effect of 3D-Printed Hearts Used in Left Ventricular Outflow Tract Obstruction: A Multicenter Study

Objective:The purpose of this research was to explore the application value of a three-dimensional (3D)-printed heart in the operation for left ventricular outflow tract (LVOT) obstruction. Methods: From August 2019 to October 2021, 46 patients with LVOT obstruction underwent surgical treatment at Peking University International Hospital, Southwest Medical University Affiliated Hospital of Traditional Chinese Medicine and Guangyuan First People's Hospital. According to the treatment method, 22 cases were allocated to the experimental group and 24 cases to the control group . The operation time, cardiopulmonary bypass time, intraoperative blood loss, hospitalization time, postoperative ejection fraction (EF), left ventricular flow velocity (LVFV), LVOT pressure difference (LVP), postoperative interventricular septal thickness (IST), inner diameter of the left ventricular outflow tract (IDLV), systolic anterior motion (SAM), atrioventricular block rate, aortic regurgitation (AR) rate and surgical complication rate of the two groups were compared. Results: The operation time, cardiopulmonary bypass time, intraoperative blood loss, hospitalization time, LVP, postoperative IST, AR, SAM, and postoperative LVFV of the experimental group were significantly lower than those of the control group (P < 0.05). The IDLV was larger than that of the control group (P < 0.05). There was no significant difference in the postoperative EF, atrioventricular block rate or complication rate between the two groups (P > 0.05). Conclusion: A 3D-printed heart model for in vitro simulation surgery is conducive to formulating a more reasonable surgical plan and reducing surgical trauma and operation time, thereby promoting the recovery and maintenance of the heart.

Blood circulation changes associated with switching to non-invasive ventilation in COVID-19 patients

Background. Various methods of respiratory support in combination with prone positioning have been used during the COVID-19 pandemic. The effects of combination of these two factors on hemodynamics are of interest for clinical practitioners.The aim: to evaluate the effect of prone positioning on hemodynamics in COVID-19 patients depending on the method of respiratory support.Materials and methods. The study included 17 patients of both sexes diagnosed with COVID-19-associated community-acquired polysegmental viral and bacterial pneumonia with progressive respiratory failure. The study consisted of two stages. During the first stage, the patients were receiving respiratory support with humidified oxygen (3–7 liters per minute). The second stage was initiated after switching to noninvasive ventilation (NIV). The measurements were performed using a technique of volumetric compression oscillometry on a non-invasive hemodynamic monitoring system KAP CGosm-Globus (Russia).Results. The study showed that prone positioning in patients with severe COVID-19 when switching from oxygen therapy to NIV resulted in a change in the diastolic blood pressure difference module from 2.5 (1.0; 8.2) to 8.0 (5.7; 14.0) (p = 0.016). Escalation of respiratory support led to the changes in the left ventricular outflow tract velocity difference module from 11.5 (9.5; 34.2) to 31.0 (15.7; 42.0) (p = 0.049).Conclusions. Patients with community-acquired polysegmental viral and bacterial pneumonia associated with COVID-19 demonstrated changes in diastolic blood pressure and left ventricular outflow tract velocity as a result of prone positioning following switching from oxygen therapy to NIV.

Altered Intercellular Communication and Extracellular Matrix Signaling as a Potential Disease Mechanism in Human Hypertrophic Cardiomyopathy

Objectives: To understand Hypertrophic Cardiomyopathy-associated alterations in gene expression and intercellular communication at the single cell level in left ventricular outflow tract lesions. Background: Human hypertrophic cardiomyopathy (HCM) is considered a disorder of the sarcomere (i.e., cardiomyocytes) but the paradoxical association of nonmyocyte phenotypes such as fibrosis, mitral valve anomalies and microvascular occlusion is unexplained. Methods: To understand the interplay between cardiomyocyte and nonmyocyte cell types in human HCM, single nuclei RNA-sequencing (snRNA-seq) was performed on myectomy specimens from HCM patients with left ventricular outflow tract obstruction and control samples from donor hearts free of cardiovascular disease. Results: Clustering analysis identified a total of 34 distinct cell populations, which were classified into 10 different cell types based on marker gene expression. Differential gene expression analysis comparing HCM to Normal datasets revealed differences in sarcomere and extracellular matrix gene expression. Analysis of expressed ligand-receptor pairs across multiple cell types indicated profound disruption in HCM intercellular communication, particularly between cardiomyocytes and fibroblasts, fibroblasts and lymphocytes and involving integrin β1 and its multiple extracellular matrix (ECM) cognate ligands. Conclusions: These findings provide evidence for intercellular interactions in HCM that link sarcomere dysfunction with altered cardiomyocyte secretion of ECM ligands, altered fibroblast ligand-receptor interactions with a variety of cell types and increased fibroblast to lymphocyte signaling, which can further alter the ECM composition, disrupt cellular function and promote nonmyocyte phenotypes.