Long-term complications following surgical patch closure of multiple muscular ventricular septal defects

Vascularization of PEGylated fibrin hydrogels increases the proliferation of human iPSC-cardiomyocytes

Studies have long sought to develop engineered heart tissue for the surgical correction of structural heart defects, as well as other applications and vascularization of this tissue has presented a challenge. Recent studies suggest that vascular cells and a vascular network may have regenerative effects on implanted cardiomyocytes (CM) and nearby heart tissue separate from perfusion of oxygen and nutrients. The goal of this study was to test whether vascular cells or a formed vascular network in a fibrin-based hydrogel would alter the proliferation of human iPSC-derived CM. First, vascular network formation in a slowly degrading PEGylated fibrin hydrogel was optimized by altering the cell ratio of human umbilical vein endothelial cells to human dermal fibroblasts, the inclusion of growth factors, and the total cell concentration. An endothelial to fibroblast ratio of 5:1 and a total cell concentration of 1.1 × 106 cells/mL without additional growth factors generated robust vascular networks while minimizing the number of cells required. Using this optimized system, human iPSC-derived CM were cultured on hydrogels without vascular cells, hydrogels with unorganized encapsulated vascular cells, or hydrogels with encapsulated vascular cells organized into networks for 7 days. CM proliferation and gene expression were assayed following 7 days of culture on the hydrogels. The presence of vascular cells in the hydrogel, whether unorganized or in vascular networks, significantly increased CM proliferation compared to an acellular hydrogel. Hydrogels with unorganized vascular cells resulted in lower CM maturity evidenced by decreased expression of cardiac troponin t (TNNT2), myosin light chain 7, and phospholamban compared to hydrogels without vascular cells and hydrogels with vascular networks. Altogether, this study details a robust method of forming rudimentary vascular networks in a fibrin-based hydrogel and shows that a hydrogel containing endothelial cells and fibroblasts can induce proliferation in adjacent CM, and these cells do not hinder CM gene expression when organized into a vascular network.

A review of the therapeutic management of multiple ventricular septal defects

BACKGROUND AND AIM

We showed in our anatomical review, ventricular septal defects existing as multiple entities can be considered in terms of three major subsets. We address here the diagnostic challenges, associated anomalies, the role and techniques of surgical instead of interventional closure, and the outcomes, including reinterventions, for each subset.

METHODS

We reviewed 80 published investigations, noting radiographic findings, and the results of clinical imaging elucidating the location, number, size of septal defects, associated anomalies, and the effect of severe pulmonary hypertension.

RESULTS

Overall, perioperative mortality for treatment of residual multiple defects has been cited to be between 0% and 14.2%, with morbidity estimated between 6% and 13%. Perioperative mortality is twice as high for perimembranous compared to muscular defects, with the need for reoperation being over four times higher. Perventricular hybrid approaches are useful for the closure of high anterior or apical defects. Overall, the results have been unsatisfactory. Pooled data reveals incidences between 2.8% and 45% for device-related adverse events. Currently, however, outcomes cannot be assessed on the basis of the different anatomical subsets.

CONCLUSIONS

We have addressed the approaches, and the results, of therapeutic treatment in terms of coexisting discrete defects, the Swiss-cheese septum, and the arrangement in which a solitary apical muscular defect gives the impression of multiple defects when viewed from the right ventricular aspect. Treatment should vary according to the specific combination of defects.

Use of Virtual Reality for Hybrid Closure of Multiple Ventricular Septal Defects

A 28-month-old girl with multiple ventricular septal defects previously underwent surgical and transcatheter attempts at repair. Three-dimensional models were created from cardiac magnetic resonance–derived images. Viewing the models in virtual reality allowed the team to precisely locate the defects and decide on a hybrid transcatheter and surgical approach to ensure successful repair. (Level of Difficulty: Advanced.)

Biventricular surgical repair of "Swiss Cheese" ventricular septal defects with two-patch and right ventricle apex excluding technique: preliminary experience and clinical results

Background

“Swiss Cheese” ventricular septal defects (VSDs) is a kind of rare and complex congenital heart defects and the surgical management remains controversial and a challenge. We reviewed our preliminary clinical experience on biventricular surgical repair of “Swiss Cheese” VSDs with two-patch and right ventricle apex excluding technique in 10 cases.

Methods

From May 2014 to December 2019, a series of 10 patients (M/F = 3/7) were admitted in our center. Nine cases underwent one-stage surgical repair with two-patch and right ventricle apex excluding technique and 1 case received two-stage surgical repair with the same technique. Surgical repair was done with cardiopulmonary bypass (CPB) in all cases. Two fresh autologous pericardium patches were used to close defects of the outflow tract area and the apex trabecular area respectively and as a result, the right ventricular apex was excluded from the right ventricular inflow tract.

Results

All operations were successful. Median CPB time and aortic clamping time were 96 min and 68 min respectively. Delayed chest closure was performed in 2 cases within 48–72 h postoperatively. The Median time of mechanical ventilation and ICU stay were 131.3 h and 8 days respectively. Median length of hospital stay after operation was 11 (9–42) days. There was no mortality and major complication except for 2 cases of ventilator associated pneumonia. There was no death and major complication during a median follow-up time of 3.2 years.. The latest echocardiography results showed the left and right heart function was normal in all the cases.

Conclusions

Biventricular surgical repair of “Swiss Cheese” VSDs with two-patch of fresh autologous pericardium and right ventricle apex excluding technique in infants is safe and feasible with favorable early and mid-term results. Long term results need to be evaluated with more cases.

Correction of simple congenital heart defects by right axillary thoracotomy in adults

BACKGROUND

Right axillary thoracotomy has been performed for open-heart procedures as a more aesthetic alternative to standard median sternotomy. This study aimed to evaluate the efficacy and safety of right axillary thoracotomy for the correction of simple congenital heart defects in adults.

METHODS

Between January 2014 and December 2017, the clinical data of 180 adults who underwent right axillary thoracotomy for simple congenital heart defects were compared with the data of a paired group of 192 adults who underwent median sternotomy.

RESULTS

Compared with the median sternotomy group, the right thoracotomy group showed shorter operative time, postoperative mechanical ventilation time, and postoperative hospitalization duration, as well as less drainage and transfusion volumes (P < .05). Aortic cross-clamping time, cardiopulmonary bypass time, and length of intensive care unit stay were similar between groups. No mortality or significant residual defects were reported in either group during follow-up. In total, 172 patients (95.6%) in the right thoracotomy group and 134 patients (69.8%) in the median sternotomy group were satisfied with their cosmetic results (P < .01).

CONCLUSIONS

A right axillary thoracotomy is as safe and effective as a median sternotomy for the correction of simple congenital heart defects in adults. With lower trauma and better cosmetic results, this procedure provides a good alternative to the standard median sternotomy.

Outcomes of Patients Undergoing Surgical Management of Multiple Ventricular Septal Defects

Surgical treatment of multiple ventricular septal defects (VSDs) has advanced significantly in recent years, yet remains technically challenging. With high rates of complications and reoperations, we sought to assess the outcomes of patients undergoing a variety of management techniques for multiple VSDs. From 1988 to 2015, 157 consecutive patients underwent surgical management of multiple VSDs at a median age of 2.2 months (2 days-16 years). Sixty-nine patients (44%) had exclusively multiple VSDs, 62 patients (39%) had multiple VSDs with concomitant intracardiac anomalies, and 26 patients (17%) had multiple VSDs with aortic arch anomalies. The predominant techniques used at the initial operations were patch closure (84 patients), pulmonary artery band (83 patients), suture closure (37 patients), and sandwich technique (13 patients). Eighteen patients underwent ventriculotomies. There were 3 hospital deaths (2%). Mean follow-up time was 8.6 ± 6 years (1 day-22 years). Four patients died during follow-up, whereas freedom from reoperations was 52% (95% confidence interval 42-61%) at 16 years. Freedom from reoperation was significantly lower in the 1988-2002 era than in the post-2002 era (38% vs 73%, P = 0.016). Pacemaker implantation was ultimately required in 9% (14 of 150) of patients. No deleterious impact of a ventriculotomy could be detected. Surgical treatment of multiple VSDs can be performed with excellent short- and long-term survival, and normal late functional outcome, however, carries a significant rate of reoperation. The recent inclusion of absorbable pulmonary artery bands and the sandwich technique appear safe and are useful adjuncts in these patients.