李飞
中国医学科学院阜外医院 心脏外科
Heart transplantation is currently the most effective treatment for end-stage heart failure; however, the shortage in donor hearts constrains the undertaking of transplantation. Mechanical circulatory support (MCS) technology has made rapid progress in recent years, providing diverse therapeutic options and alleviating the dilemma of donor heart shortage. The ventricular assist device (VAD), as an important category of MCS, demonstrates promising applications in bridging heart transplantation, destination therapy, and bridge-to-decision. VADs can be categorized as durable VADs (dVADs) and temporary VADs (tVADs), according to the duration of assistance. With the technological advancement and clinical application experience accumulated, VADs have been developed in biocompatible, lightweight, bionic, and intelligent ways. In this review, we summarize the development history of VADs, focusing on the mechanism and application status of dVADs in detail, and further discuss the research progress and use of VADs in China.
Journal of cardiovascular development and disease 2024
Purpose:To investigate myocardial remodeling using cardiac MRI (CMR) feature tracking (FT) and to explore the relationship between CMR parameters with outcomes in hypertrophic obstructive cardiomyopathy (HOCM) after myectomy.Materials and Methods:In this single-center retrospective study, patients with HOCM undergoing myectomy between 2011 and 2019 were included. Pre- and postmyectomy global and regional strains were compared. Healthy participants were included for comparison. Composite events were recorded at follow-up performed after a minimum of 12 months. The paired-samples t test was utilized to compare pre- and postmyectomy variables.Results:A total of 73 patients (44 years ± 14 [SD]; 45 men) were evaluated. Compared with preoperative parameters, global circumferential strain (CS) (-17.6% ± 4.4 vs -16.7% ± 3.9, P = .02) was impaired, but global longitudinal strain (LS) was improved (-9.3% ± 2.8 vs -10.8% ± 3.3, P < .001). Septal CS (-14.2% ± 4.0 vs -11.0% ± 4.4, P < .001) and septal radial strain (RS) (16.4% ± 10.6 vs 13.7% ± 9.5, P = .007) worsened, while septal LS (-8.1% ± 3.5 vs -10.2% ± 3.4, P < .001), lateral RS (40.1% ± 16.6 vs 54.4% ± 22.6, P < .001), lateral CS (-20.2% ± 4.1 vs -23.1% ± 4.8, P < .001), and lateral LS (-5.6% ± 5.6 vs -8.4% ± 5.2, P = .001) were improved. Sixteen of 73 patients (22%) experienced composite events after median follow-up of 39.1 months. Postoperative global CS provided the highest discrimination for composite event occurrence (area under the receiver operating characteristic curve, 0.73; 95% CI: 0.61, 0.83) with a cutoff of -16.7%. Patients with postoperative global CS greater than -16.7% had reduced event-free survival compared with those with postoperative global CS less than or equal to -16.7% (log-rank P = .002).Conclusion:CMR-FT analysis demonstrated longitudinal and lateral restorations, but impaired global CS, after myectomy in patients with HOCM; furthermore, increased global CS was associated with poorer outcomes.Keywords: MR Imaging, Cardiac, Outcomes Analysis, Comparative Studies, Surgery© RSNA, 2022 Supplemental material is available for this article.
Radiology. Cardiothoracic imaging 2022
This study aimed to assess the relationship between local mechanical stimuli and regional aortic tissue degeneration using fluid-structure interaction (FSI) analysis in patients with bicuspid aortic valve (BAV) disease. Nine patients underwent ascending aortic replacement were recruited. Tissues were collected to evaluate the pathology features in four regions, greater curvature (GC-region), posterior (P-region), anterior (A-region), and lesser curvature (LC-region). FSI analysis was performed to quantify vessel structural stress (VSS) and flow-induced parameters, including wall shear stress (WSS), oscillatory shear index (OSI), and particle relative residence time (RRT). The correlation between these biomechanical metrics and tissue degeneration was analyzed. Elastin in the medial layer and media thickness were thinnest and the gap between fibers was biggest in the GC-region, followed by the P-region and A-region, while the elastin and media thickness were thickest and the gap smallest in the LC-region. The collagen deposition followed a pattern with the biggest in the GC-region and least in the LC-region. There is a strong negative correlation between mean or peak VSS and elastin thickness in the arterial wall in the GC-region (r = -0.917; p = 0.001 and r = -0.899; p = 0.001), A-region (r = -0.748; p = 0.020 and r = -0.700; p = 0.036) and P-region (r = -0.773; p = 0.014 and r = -0.769; p = 0.015), and between mean VSS and fiber distance in the A-region (r = -0.702, p = 0.035). Moreover, strong negative correlation between mean or peak VSS and media thickness was also observed. No correlation was found between WSS, OSI, and RRT and aortic tissue degeneration in these four regions. These findings indicate that increased VSS correlated with local elastin degradation and aortic media degeneration, implying that it could be a potential biomechanical parameter for a refined risk stratification for patients with BAV.
Journal of biomechanics 2021
This study assesses the long-term outcomes of patients who suffered from self-expandable transcatheter heart valve (THV) embolized in the aorta in transcatheter aortic valve implantation (TAVI).We retrospectively reviewed the patients with self-expandable THV embolized in the aorta. Follow-up computed tomography was performed to assess the THV migration, struct fractures, and device-related aortic complications.Of the 539 TAVI patients, 11 suffered from self-expandable THV embolized in the aorta. Two patients underwent open-heart surgery to remove the embolized THVs in the ascending aorta. Embolized THVs were repositioned in the aortic arch distal to the left subclavian artery (n = 3) and the thoracic descending aorta (n = 6). Three patients died during a median follow-up time of 40 months. The remaining eight survivors presented with New York Heart Association functional class I or II at the last follow-up. Degeneration of embolized prostheses with thick leaflets and rolled cusp edges was observed in three patients. There was no evidence of valve migration, strut fracture, prosthesis-associated aortic complication, and thrombosis attached on embolized valve for all patients with THVs repositioned in the aorta.Self-expandable THV embolization can be effectively managed in TAVI. Although some embolized valves exhibited leaflet degeneration, the long-term safety of repositioning embolized self-expandable THV in the aorta is assured.
International heart journal 2021
Objective: To examine the early outcome of valve sparing aortic root replacement with reimplantation technique (David procedure) with partial upper sternotomy. Methods: From April 2016 to April 2020, 31 patients underwent valve sparing aortic root replacement under partial upper sternotomy at Vascular Surgery Center, Fuwai Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College. There were 28 males and 3 females, aging (44±13) years (range: 11 to 65 years). Preoperative aortic regurgitation was found greater than moderate in 15 patients, moderate in 6 patients and less than moderate in 10 patients. The diameter of aortic annulus was (26±3) mm (range: 21 to 34 mm), the diameter of aortic sinus was (51±6) mm (range: 41 to 68 mm), the diameter of ascending aorta was (43±8) mm (range: 26 to 62 mm). The preoperative ejection fraction was (65±4) % (range: 59% to 72%) and left ventricular end-diastolic diameter was (55±6) mm (range: 42 to 68 mm). All cases were treated with David Ⅰ procedure, including simple David procedure in 26 patients, David+ascending aorta and partial aortic arch replacement in 3 patients, David+thoracic endovascular aortic repair in 1 patient, David+stent elephant trunk implantation in 1 patient. Results: The operation time, cardiopulmonary bypass time and aortic cross-clamping time were (330±58) minutes (range: 214 to 481 minutes), (138±23) minutes (range: 106 to 192 minutes) and (108±17) minutes (range: 82 to 154 minutes), respectively. There were no death and serious complications (stroke, myocardial infarction, renal insufficiency, severe infection, etc.). The postoperative drainage volume within 24 hours was (314±145) ml (range: 130 to 830 ml). The intubation time was (14±3) hours (range: 8 to 21 hours), and the ICU time was (M(QR)) 2.1(1.5) days (range: 1.0 to 5.0 days). Eight patients had no blood transfusion, the proportion of red blood cell use was 9.7% (3/31), plasma use was 22.6% (7/31), and platelet use was 71.0% (22/31). The postoperative left ventricular ejection fraction was (62±4)% (range: 54% to 69%), and left ventricular end-diastolic diameter was (48±4) mm (range: 39 to 56 mm). After operation, aortic regurgitation was significantly improved, with no more than moderate regurgitation, small to moderate regurgitation in 3 patients, minor regurgitation in 3 patients, micro regurgitation in 12 patients and no regurgitation in 13 patients. The follow-up period was 3.5(6.1) months (range: 2.0 to 39.0 months). Echocardiographic follow-up data were obtained in 26 cases, including moderate regurgitation in 1 patient, small to moderate regurgitation in 9 patients, minor regurgitation in 5 patients, micro regurgitation in 6 patients and no regurgitation in 5 patients. There were no major adverse cardiovascular events and aortic events during the follow-up period. No patient was reoperated for aortic regurgitation. Conclusion: Valve sparing aortic root replacement under partial upper sternotomy is safe and feasible, and the early result is satisfactory.
Zhonghua wai ke za zhi [Chinese journal of surgery] 2021
Divergence-free smoothing with wall treatment (DFSwt) method is proposed for processing with four-dimensional (4D) flow magnetic resonance imaging (MRI) data of blood flows to enhance the quality of flow field with physical constraints. The new method satisfies the no-slip wall boundary condition and applies wall function of velocity profile for better estimating the velocity gradient in the near-wall region, and consequently improved wall shear stress (WSS) calculation against the issue of coarse resolution of 4D flow MRI. In the first testing case, blood flow field obtained from 4D flow MRI is well smoothed by DFSwt method. A great consistency is observed between the post-processed 4D flow MRI data and the computational fluid dynamics (CFD) data in the interested velocity field. WSS has an apparent improvement due to the proposed near-wall treatment with special wall function comparing to the result from original 4D flow MRI data or the DFS-processed data with no wall function. The other five cases also show the same performance that smoothed velocity field and improved WSS estimation are achieved on 4D flow MRI data optimized by DFSwt. The improvements will benefit the study of hemodynamics regarding the determination of location or the potential possibility of lesions.
Medical & biological engineering & computing 2021
INTRODUCTION:Primary benign right ventricular tumours are rare. They can cause significant mortality without appropriate and timely treatment. We investigated surgical treatment and survival characteristics for right ventricular tumours.MATERIALS AND METHODS:From 2007 to 2017, 21 patients with primary benign right ventricular tumours who underwent tumour resection were retrospectively reviewed. Clinical findings and follow-up results were analysed.RESULTS:Thirteen men and eight women were enrolled, with a mean age of 42.3 ± 15.3 years. The most frequent histotypes were myxoma, haemangioma and papillary fibroelastoma. Eight patients underwent concomitant tricuspid valvuloplasty and one had tricuspid valve replacement. No major adverse events or death occurred during the perioperative period. One patient with haemangioma underwent partial tumour resection; however, the tumour regressed gradually during follow-up. Within the 10-year follow-up period (mean 4.8 ± 2.6 years), the recurrence-free and overall survival rates were 81.0% and 85.7%, respectively.CONCLUSIONS:Tumour resection for primary benign right ventricular tumours is safe and effective, and has a good prognosis. Tricuspid valvuloplasty or tricuspid valve replacement may be necessary for the resection of right ventricular tumours to improve the haemodynamics. Haemangiomas naturally undergo spontaneous regression.
Annals of the Royal College of Surgeons of England 2021
OBJECTIVE:Our study aimed to evaluate short- and long-term outcomes of patients who required emergent conversion from transcatheter aortic valve implantation (TAVI) to open surgery. Besides, the reasons and procedural settings of emergent cardiac surgery (ECS) were also reported.METHODS:We retrospectively reviewed the patients who underwent TAVI in our institution between 2012 and 2019 and collected the clinical data of cases who converted from TAVI to bail-out surgery. Telephone and outpatient follow-ups were performed.RESULTS:Of 516 TAVI patients, 20 required ECS, and the bail-out surgery occurred less frequently with the increase in TAVI volume. The most common reason for conversion was left ventricular perforation (7/20, 35.0%). Thirty-day mortality was 35.0% in ECS patients. Kaplan-Meier survival curves showed that the cumulative survival rate was 65.0% at 1 year, 50.1% at 5 years in all ECS patients, and 77.1% at 5 years in patients who survived over 30 days after conversion.CONCLUSION:Although the bail-out operation was performed immediately after TAVI abortion, ECS still associated with high 30-day mortality. The long-term survival benefit was seen in patients surviving from bail-out surgery. An experienced TAVI team is of crucial importance in avoiding ECS-related life-threatening complications and providing effective salvage surgery.
Annals of thoracic and cardiovascular surgery : official journal of the Association of Thoracic and Cardiovascular Surgeons of Asia 2021
PURPOSE:The dilation of proximal arch (PArc) was suspected to develop as a result of valve-related hemodynamics or in consequence to the upward extension of the ascending aorta (AAo) dilation. We aimed to investigate the one that could be the possible contributing factor in patients with bicuspid aortic valve (BAV).METHODS:All enrolled BAV patients underwent four-dimensional flow magnetic resonance imaging. Contour-averaged circumferential wall shear stress (WSScirc,avg) and the diameter of the middle of AAo (mid-AAo) were compared between the patients with and without PArc dilation. Additionally, we analyzed the correlation between WSScirc,avg and aortic diameter at PArc section, as well as the correlation between the diameter of mid-AAo and that of PArc.RESULTS:No significant difference was observed in WSScirc,avg at PArc section between the patients with and without PArc dilation (P = .621). However, the diameter of mid-AAo in the patients who suffered PArc dilation was higher than those without it (P = .007). In addition, the aortic diameter did not correlate with the WSScirc,avg at PArc level (R = -0.068, P = .701). The correlation was observed between PArc diameter and mid-AAo diameter (R = 0.521, P = .002).CONCLUSION:Hemodynamics may not contribute to the development of PArc dilation. PArc diameter correlated with mid-AAo diameter, indicating PArc dilation may be secondary to the upward extension of AAo dilation. The influence of AAo dilation extending upward could be treated by AAo replacement; hence, a selective approach to transverse PArc replacement might be appropriate.
The heart surgery forum 2020
BACKGROUND:Valve-related hemodynamics and intrinsically regulated matrix proteases are 2 determined pathogenetic factors associated with medial elastin degeneration in bicuspid aortopathy. This study analyzed the association between elastic fiber deterioration and the 2 pathogenetic factors in ascending and root morphotypes, aiming to elucidate the etiological heterogeneity between the 2 morphotypes.METHODS:Four-dimensional flow cardiac magnetic resonance was used to measure the regional wall shear stress (WSS) on the ascending aorta, and matrix metalloproteinase (MMP) expression was assessed by immunoblotting. After histopathology analysis of aortic tissue, we assessed whether elevated regional WSS and increased MMP expression corresponded with medial elastin thinning.RESULTS:Increased regional WSS corresponded with medial elastin thinning in both morphotypes. Increased expression of different MMP isoforms corresponded with medial elastin degeneration in bicuspid aortopathy. The significantly increased expression of MMP-2 corresponded with a decrease of elastic fiber thickness in the ascending morphotype (P = .046), whereas elastic fiber thinning was associated with high levels of MMP-3 expression (P = .012) in the root morphotype. No association was observed between regional WSS and MMP expression.CONCLUSION:There is no difference in the effect of valve-related hemodynamics between ascending and root morphotype, and MMPs are not involved in the process of elastic fiber degeneration induced by increased WSS. The increased expression of different MMP isoforms was observed in the context of elastic fiber degeneration between the 2 morphotypes, implying that heterogeneity between them is revealed in the different intrinsic pathway of medial elastin degradation.
The heart surgery forum 2020
