Improved mid-term stability of MR reduction with an increased number of clips after percutaneous mitral valve repair in functional MR

Background

Percutaneous mitral valve repair (PMVR) has evolved to be a standard procedure in suitable patients with mitral regurgitation (MR) not accessible for open surgery. Here, we analyzed the influence of the number and positioning of the clips implanted during the procedure on MR reduction analyzing also sub-collectives of functional and degenerative MR (DMR).

Results

We included 410 patients with severe MR undergoing PMVR using the MitraClip® System. MR and reduction of MR were analyzed by TEE at the beginning and at the end of the PMVR procedure. To specify the clip localization, we sub-divided segment 2 into 3 sub-segments using the segmental classification of the mitral valve.

Results

We found an enhanced reduction of MR predominantly in DMR patients who received more than one clip. Implantation of only one clip led to a higher MR reduction in patients with functional MR (FMR) in comparison to patients with DMR. No significant differences concerning pressure gradients could be observed in degenerative MR patients regardless of the number of clips implanted. A deterioration of half a grade of the achieved MR reduction was observed 6 months post-PMVR independent of the number of implanted clips with a better stability in FMR patients, who got 3 clips compared to patients with only one clip.

Conclusions

In patients with FMR, after 6 months the reduction of MR was more stable with an increased number of implanted clips, which suggests that this specific patient collective may benefit from a higher number of clips.

Outcomes of total anomalous pulmonary venous drainage repair in neonates and the impact of pulmonary hypertension on survival

Background

Mortality after repair of total anomalous pulmonary venous drainage (TAPVD) in neonates has remained high. Analysis of risk factors may help identify therapeutic targets to improve survival.

Methods

Retrospective analysis of all neonates who underwent simple TAPVD repair.

Results

Between 1973 and 2021, 175 neonates underwent TAPVD repair, at a median age of 6 days (interquartile range, 2-15 days) and a mean weight of 3.2 ± 0.6 kg. TAPVD was supracardiac in 42.3% of the patients (74 of 175), cardiac in 14.3% (25 of 175), infracardiac in 40% (70 of 175), and mixed type in 3.4% (6 of 175), with obstruction in 65.7% (115 of 175). Pulmonary hypertension (PHT) crisis occurred in 12% (21 of 175). Early mortality was 9.7% (17 of 175) and late mortality was 5.1% (8 of 158), with most deaths occurring within 1 year (75%; 6 of 8). Survival was 86.5% (95% CI, 80.3%-90.8%) at 1 year and 85.8% (95% CI, 79.6%-90.3%) at 5, 10, 15, and 20 years. Survival was lower in patients with obstructed TAPVD, patients with emergent surgery, and those with PHT crisis. PHT crisis (hazard ratio [HR], 4.93; 95% CI, 1.95-12.51; P = .001), urgency of surgery (HR, 2.51; 95% CI, 1.11-5.68; P = .027), and higher pulmonary artery pressure-to-systemic blood pressure percentage ratio (HR, 1.06; 95% CI, 1.01-1.11; P = .026) were identified as risk factors for mortality. Histopathological analysis of 17 patients (9.7%; 17 of 175) showed signs of pulmonary arterial hypertension with media hypertrophy in 58.8% (10 of 17).

Conclusions

Mortality after TAPVD repair occurred mainly within the first year of life. Urgency of surgery and persistent PHT appears to be risk factors for mortality. Lung biopsy might be useful for identifying patients at risk and guiding newer treatment modalities.

Nitric oxide and viral infection: Recent developments in antiviral therapies and platforms

Nitric oxide (NO) is a gasotransmitter of great significance to developing the innate immune response to many bacterial and viral infections, while also modulating vascular physiology. The generation of NO from the upregulation of endogenous nitric oxide synthases serves as an efficacious method for inhibiting viral replication in host defense and warrants investigation for the development of antiviral therapeutics. With increased incidence of global pandemics concerning several respiratory-based viral infections, it is necessary to develop broad therapeutic platforms for inhibiting viral replication and enabling more efficient host clearance, as well as to fabricate new materials for deterring viral transmission from medical devices. Recent developments in creating stabilized NO donor compounds and their incorporation into macromolecular scaffolds and polymeric substrates has created a new paradigm for developing NO-based therapeutics for long-term NO release in applications for bactericidal and blood-contacting surfaces. Despite this abundance of research, there has been little consideration of NO-releasing scaffolds and substrates for reducing passive transmission of viral infections or for treating several respiratory viral infections. The aim of this review is to highlight the recent advances in developing gaseous NO, NO prodrugs, and NO donor compounds for antiviral therapies; discuss the limitations of NO as an antiviral agent; and outline future prospects for guiding materials design of a next generation of NO-releasing antiviral platforms.