Bilateral remote ischemic conditioning in children: A two-center, double-blind, randomized controlled trial in young children undergoing cardiac surgery

Objective

The study objective was to determine whether adequately delivered bilateral remote ischemic preconditioning is cardioprotective in young children undergoing surgery for 2 common congenital heart defects with or without cyanosis.

Methods

We performed a prospective, double-blind, randomized controlled trial at 2 centers in the United Kingdom. Children aged 3 to 36 months undergoing tetralogy of Fallot repair or ventricular septal defect closure were randomized 1:1 to receive bilateral preconditioning or sham intervention. Participants were followed up until hospital discharge or 30 days. The primary outcome was area under the curve for high-sensitivity troponin-T in the first 24 hours after surgery, analyzed by intention-to-treat. Right atrial biopsies were obtained in selected participants.

Results

Between October 2016 and December 2020, 120 eligible children were randomized to receive bilateral preconditioning (n = 60) or sham intervention (n = 60). The primary outcome, area under the curve for high-sensitivity troponin-T, was higher in the preconditioning group (mean: 70.0 ± 50.9 μg/L/h, n = 56) than in controls (mean: 55.6 ± 30.1 μg/L/h, n = 58) (mean difference, 13.2 μg/L/h; 95% CI, 0.5-25.8; P = .04). Subgroup analyses did not show a differential treatment effect by oxygen saturations (pinteraction = .25), but there was evidence of a differential effect by underlying defect (pinteraction = .04). Secondary outcomes and myocardial metabolism, quantified in atrial biopsies, were not different between randomized groups.

Conclusions

Bilateral remote ischemic preconditioning does not attenuate myocardial injury in children undergoing surgical repair for congenital heart defects, and there was evidence of potential harm in unstented tetralogy of Fallot. The routine use of remote ischemic preconditioning cannot be recommended for myocardial protection during pediatric cardiac surgery.

Outcomes of manually modified microvascular plugs to pulmonary flow restrictors in various congenital heart lesions

Background

The development of microvascular plugs (MVPs) has enabled novel transcatheter deliverable endoluminal pulmonary flow restrictors (PFRs) with the potential to treat newborns and infants with life-threatening congenital heart diseases (CHDs) in a minimally invasive manner. We present our experience to evaluate the efficacy of this concept in controlling pulmonary blood flow in various CHDs.

Methods

Retrospective clinical data review of patients with CHD and pulmonary over-circulation who received bilateral PFRs percutaneously.

Results

Twenty-eight PFRs (7 MVP-5Q, 12 MVP-7Q, and 9 MVP-9Q) were finally implanted in 14 patients with a median age of 1.6 months (IQR, 0.9-2.3) and a median weight of 3.1 Kg (IQR, 2.7-3.6). Nine patients had large intra-cardiac left-to-right shunts (including 3 with fatal trisomy and palliative programs), 2 had borderline left ventricles, 2 had Taussig-Bing anomaly, and one had a hypoplastic left heart. Four patients had concomitant ductal stenting. Two MVP-5Qs were snare-removed and upsized to MVP-7Q. Patients experienced a significant drop in oxygen saturation and Qp/Qs. All patients were discharged from the ICU after a median of 3.5 days (IQR, 2-5.8) postoperative. Five patients had routine inter-stage catheterization and no device embolization or pulmonary branch distortion was seen. Fourteen (50%) PFRs were surgically explanted uneventfully on a median of 4.3 months (IQR, 1.2-6) post-implantation during biventricular repair in 6 patients and stage-2 palliation in one patient. The latter died 1 month post-operative from severe sepsis. Four patients are scheduled for surgical PFR removal and biventricular repair. Two patients with trisomy 18 died at 1 and 6.8 months post-procedure from non-cardiac causes. One patient with trisomy 13 is alive at 2.7 months post-procedure.

Conclusion

It is feasible to bespoke MVPs and implant them as effective PFRs in various CHDs. This approach enables staged left ventricular recruitment, comprehensive stage-2 or biventricular repair with lower risk by postponing surgeries to later infancy. Device explantation is uneventful, and the outcomes afterward are promising.

Chiari zero malformation with syringobulbia

Chiari zero malformation is a relatively new and rare subtype of Chiari malformations. Most of the patients present with signs and symptoms of Chiari malformation without actual cerebellar tissue herniation, with or without syringomyelia. Furthermore, Chiari zero cases can be associated with syringobulbia in rare instances. We present a case of a 39-year-old patient diagnosed with Chiari zero associated with syringomyelia and syringobulbia.

Comparative analysis of surgical and percutaneous pulmonary valve implants over a 20-year period

OBJECTIVES

Since percutaneous pulmonary valve implantation (PPVI) was introduced to prolong the lifetime of surgically placed right ventricular to pulmonary artery conduits, valve technology has evolved and the indications for PPVI expanded to native and larger right ventricular outflow tracts. We explore how indications, patient populations and outcomes compare to surgical pulmonary valve replacement (PVR).

METHODS

This is a retrospective cohort study of PPVI and PVR procedures between 1998 and 2020 at a single UK centre. One hundred and twenty-eight patients underwent PPVI and 365 patients PVR. Primary outcome measures were survival, infective endocarditis and reintervention.

RESULTS

The most common indication for PVR was replacement of the native pulmonary valve for pulmonary regurgitation whereas PPVI was more commonly used to treat pulmonary stenosis in a previously placed bioprosthetic conduit or valve. Treatment indications for PPVI expanded over the study to include the native right ventricular outflow tract. Survival was similar for PPVI and PVR (92% PPVI and 96.8% PVR at 5 years; 85.8% PPVI and 95.1% PVR at 10 years). Preprocedural New York Heart Association class 3 and 4 was the most important predictor of poor outcome. Annualized infective endocarditis rate was significantly higher for the Melody PPVI (0.024 vs 0.0024/person/year for PVR, P < 0.05). Both groups showed significant symptomatic improvement postprocedure with remodelling of ventricular volumes and improvement in cardiac output. Long-term follow-up for PVR showed half of patients will need replacement at 10-15 years post-index procedure.

CONCLUSIONS

An increasing number of patients requiring PVR can now be treated percutaneously. A lifetime strategy for re-valving should be considered at the first valve implant.

The Ross-Konno operation for neonates and infants with severe aortic incompetence following treatment for critical aortic stenosis

OBJECTIVES

Aortic valve stenosis in neonates and infants is associated with congestive cardiac failure, and balloon or surgical valvuloplasty provides relief of stenosis. Occasionally severe aortic insufficiency necessitates urgent aortic valve replacement. We reviewed our experience with the Ross-Konno procedure in patients <1 year.

METHODS

Between October 2013 and May 2020, 36 patients underwent balloon (34) or surgical (2) aortic valvuloplasty for aortic stenosis. Six patients subsequently underwent a Ross-Konno procedure. The median age at operation was 55 (27-116) days and weight was 4.25 (2.5-12) kg. All patients were in severe cardiac failure and had a small aortic annulus with Z-score -3.1 (-1 to -4.4).

RESULTS

There were no early or late deaths. At the latest follow-up at 39 (13-60) months, ventricular function had improved in all patients and no patient was on anti-failure medication. On echocardiography, there wasno more than trivial aortic regurgitation and no left ventricular outflow tract obstruction. One patient required right ventricle to pulmonary artery conduit replacement and one patient had homograft stenting.

CONCLUSIONS

Despite the severe preoperative haemodynamic compromise, the urgent Ross-Konno procedure was associated with excellent operative survival and recovery of ventricular function. The need for reintervention to the pulmonary conduit remains a cause for concern.

Outcomes of extraskeletal vs. skeletal Ewing sarcoma patients treated with standard chemotherapy protocol

PURPOSE

To compare the outcomes of extraskeletal and skeletal Ewing sarcomas treated with standard chemotherapy protocol.

METHODS

We retrospectively collected data on primary localized skeletal and extraskeletal ES patients. Demographics and disease characteristics were compared between the two groups. The influence of presentation (skeletal vs. extraskeletal) on overall survival (OS) and local recurrence-free survival (LRFS) was assessed and compared by the log-rank test.

RESULTS

A total of 120 patients were included; 29 (24%) had extraskeletal and 91 (76%) had skeletal ES. All patients received vincristine, doxorubicin, and cyclophosphamide alternating with ifosfamide and etoposide (VDC-IE) chemotherapy, with a plan for local control at week 12. At a median follow-up of 38 months, there was no difference in OS between skeletal and extraskeletal ES; 5-year OS 70% and 67% respectively, p = 0.96. Patients with extraskeletal ES had inferior 5-year LRFS compared to skeletal ES; 74% vs. 83%; p = 0.042. Local recurrence occurred at a higher frequency in the extraskeletal group; 28% vs. 11%, p = 0.034, although more extraskeletal patients received adjuvant radiotherapy; 73% vs. 36%, p = 0.01. Among patients who underwent surgery (n = 76), there was no difference in R0 resection rate (skeletal: 89%, extraskeletal: 86%, p = 0.52, or good ( ≥ 90%) tumor necrosis; skeletal: 54%, extraskeletal: 38%, p = 0.31.

CONCLUSION

Patients with localized extraskeletal ES have comparable OS outcomes to patients with skeletal ES utilizing the standard VDC-IE chemotherapy. However, extraskeletal patients are at significantly higher risk for local recurrence.

The circumferential loading of a direct cardiac compression assist device

Heart disease is the developed world's largest killer. Transplantation of the failing heart remains the most effective treatment currently employed, but demand far exceeds donor supply. In a bid to address this imbalance, the use of mechanical circulatory support has been explored since the mid-1960s. This paper utilizes one such device, which achieves assistance by mechanically compressing the epicardial surface of the failing heart. The circumferential normal loading of the device is investigated, showing how frictional effects inherent to the device's operation affect localized surface pressure. Results showed that as distance from the device's actuator increased, assistive systolic force reduced, whilst device constriction to ventricular filling detrimentally increased. Active device relaxation was shown to limit the diastolic effect outlined above, providing the simulated diseased heart with an improved cardiac output. The results also raise questions concerning device in-vivo positioning and short-comings with the current heart simulator.

Combined severe pectus excavatum correction and aortic root replacement in Marfan's syndrome

A 23-year-old man with Marfan's syndrome was admitted for repair of annulo-aortic ectasia and severe pectus excavatum. A submammary skin incision approach followed by bilateral subperichondrial resection of abnormal costal cartilages was performed. The left intercostal muscles and perichondrial sheaths were divided 2 inches lateral to the sternum in a parasternal fashion to place the retractor. The aortic root was replaced with a 23-mm St. Jude's composite graft (St. Jude Medical, Inc, St. Paul, MN). Chest wall reconstruction was completed with a high sternal osteotomy and support of the sternum was made with Gortex strips (W.L. Gore & Associates, Inc, Flagstaff, AZ). The patient made an uneventful recovery.

Mini-sternotomy for aortic valve surgery

In the recent years more and more efforts have been made widely to introduce new techniques in the minimally invasive cardiac surgery. At our Department and the Linköping University Hospital, Cardiothoracic Surgery Department, from August 1996 to January 1997, aortic valve surgery was performed in 23 adult patients (9 female, 14 male), age 28-86 years (mean age 62.5 years). Twenty-two patients had aortic valve replacement, among these, in 3 cases concomitant aortic annulus dilatation was made and in one case reduction-plasty of the dilated ascending aorta. In another one case resection of a sub-aortic membrane was performed. The operations and postoperative period were free of complications in all patients. Following an average 36 hours intensive care all patients were discharged after an average of 11.2 day hospital stay. The authors introduce the new surgical technique and present its advantages and disadvantages. Mini-sternotomy has less detrimental structural and functional effects on the thorax. Moreover, due to its minimal surgical trauma, this less invasive technique reduces patient morbidity, hospital stay and cost of care. Since mini-sternotomy is a safe and advantageous technique, the authors recommend applying this new technique in most of aortic valve operations.