Left bundle branch pacing after transcatheter aortic valve implantation. Initial experience of a center

Introduction

Permanent pacing is often needed in patients with severe aortic stenosis undergoing transcatheter aortic valve implantation (TAVI) due to new onset conduction disorders. Nevertheless, continuous right ventricular pacing may deteriorate left ventricular ejection fraction (LVEF) and lead to poor outcomes. Thus, in last years, more physiological forms of pacing, such as left bundle branch pacing (LBBP) have been developed to prevent pacing induced cardiomyopathy.

Purpose

The aim of our study is to describe the initial experience in our center, evaluate the safety and feasibility of LBBP after TAVI and describe electrophysiological outcomes in the first months of follow-up.

Methods

We designed a prospective registry that collected all patients from the TAVI program of our center who developed conduction abnormalities in the immediate postoperative and received LBBP. We analyzed baseline characteristics, complications and procedure time, electrophysiological parameters after the procedure and final QRS interval. During follow-up LVEF, electrophysiological parameters and adverse clinical events (readmissions for heart failure, cardiovascular mortality and all-cause of mortality) were also evaluated at 3rd, 6th and 12th month.

Results

Between January 2020 and January 2022, twenty patients who developed conduction abnormalities after TAVI underwent LBBP. Seven patients (35%) had a complete atrioventricular block, two patients (10%) alternating bundle branch block and 11 (55%) had a new left bundle branch block. HV electrophysiology study was performed in 8 patients, with a median value of 68ms (66–72).

Of the 20 patients, 3 out of 4 patients were male and had history of hypertension. 40% had previous ischemic heart disease and one patient had transthyretin cardiac amyloidosis. Median age was 79 years-old (76–83.5). Balloon-expandable prosthesis was implanted in 11 patients while 9 received a self-expandable prosthesis. Median basal LVEF was 59% (41.5–60) and median NTproBNP was 1722pg/ml (535–5848).

LBBP was successful in all of the 20 patients. The median time of the procedure was 60 minutes (45–80) without suffering any complications. The median QRS interval before the procedure was 155ms (140–158) and 116ms (105–125) post-implant.

To date, two patients have died of non-cardiac cause 3 and 8 months after LBBP. There have been no readmissions for heart failure. LVEF (pre and post-LBBP) and electrophysiological parameters post-implant and three-month follow-up are shown in Table 1.

Conclusions

In our experience, LBBP after TAVI is a safe and feasible procedure. Despite the small sample size and short follow-up period, our first results indicate stability of LVEF and pacemaker parameters.

Funding Acknowledgement

Type of funding sources: None.

Cardiac allograft vasculopathy and acute rejection surveillance in the same procedure through a single vascular access. High volume center experience

Introduction

Cardiac Allograft Vasculopathy (CAV) and Acute Rejection (AR) surveillance after a Heart Transplant (HT) is based on the performance of Coronary Angiography (CAG) that requires arterial access and Endomyocardial Biopsy, normally Ventricular Right (RV-EMB), which requires venous access. Depending on the clinical indication, HT patients are referred to the cath lab to perform both procedures in the same day. We evaluated the effectiveness and safety of performing a Left Ventricular Endomyocardial Biopsy (LV-EMB) and a CAG with a single artery access.

Methods

We retrospectively analyzed HT patients referred to cath lab for surveillance of AR and CAV on the same day between January 2018 and March 2021. We compared the procedures performed with two accesses (Group 1; CAG + RV-EMB) versus procedures made with a single artery access (Group 2; CAG + LV-EMB).

Results

121 Procedures were performed within the indicated period, 96 (79.3%) belong to the double access group and 25 (20.7%) to the single access group. All procedures were successful and without major complications. There were only 2 cases of insufficient sample, one for each group. Baseline characteristics in both groups and AR or CAV presence were similar (table). Total procedure time (52.00±15.30 vs 33.36±18.69min) and fluoroscopic time (10.70±4.89 vs 6.84±1.82 min) were significantly shorter in the single access group (p<0.001 in both). The most used arterial access in group 2 was the right radial artery (15; 60%) followed by the right femoral artery (5; 20%).

Conclusions

Performing an endomyocardial biopsy and coronary angiography through a single arterial access is as effective and safe as with double access, arterial and additional venous. Procedure time and fluoroscopic time is significantly less when it is performed through the same access.

Funding Acknowledgement

Type of funding sources: None.

Prospective evaluation of donor-derived cell-free DNA as a potential biomarker for cardiac allograft vasculopathy

Background

Cardiac allograft vasculopathy (CAV) remains a major cause of morbidity and mortality among long-term heart transplant (HT) recipients. There is clearly an unmet need for a noninvasive biomarker of CAV that could obviate the need to perform surveillance coronary angiograms in these patients.

Purpose

Our aim was to evaluate the performance of Donor-derived Cell Free DNA (dd-cfDNA) as a biomarker of CAV.

Methods

We prospectively measured dd-cfDNA levels in all consecutive asymptomatic patients undergoing surveillance coronary angiography >1 year after HT at a single center, between Jan 2019 and Jan 2021. Endpoints included the association between dd-cfDNA levels and the presence CAV, according to ISHLT 2010 classification. Patients with history of acute cellular rejection ≥1R or antibody mediated rejection in the previous 6 months were excluded.

Results

We included 94 HT recipients, median age 57 years (IQR 50–67), 67% men, a median of 10.9 years after transplant. Coronary angiogram revealed CAV0, CAV1, CAV2 and CAV3 in 61%, 19%, 14% and 6% of patients, respectively. Median dd-cfDNA values for each CAV group were: CAV0 0.92% (IQR 0.46–2.0), CAV1 1.4% (0.38–2.8), CAV2 0.17% (0.07–0.52) and CAV3 0.24% (0.057–0.87); p=0.0535. Figure 1 summarizes baseline characteristics of the cohort and results.

Comparison of dd-cfDNA levels in patients with CAV0 and CAV1–2-3 did not show significant differences (0.92%, IQR 0.46–2.0 vs 0.46%, IQR 0.075–1.5, p=0.059) (Figure 2A), nor did the comparison between patients with stable CAV (no new coronary lesions since previous angiogram, n=77) and progressive CAV (patients with new coronary stenoses, n=17); median dd-cfDNA values were 0.735% (IQR 0.195–2.0) vs 0.9% (IQR 0.12–1.8), p=0.76 (Figure 2B). A subanalysis according to time after HT was also found non-significant: less than 5 years (p=0.95), 5 to 10 years (p=0.14) and more than 10 years after HT (p=0.16) (Figure 2C). The AUC ROC curve for the diagnosis of CAV revealed the lack of ability to predict the presence of any degree of CAV (AUC ROC = 0.38).

Conclusion

In our experience, dd-cfDNA did not perform as a useful biomarker to avoid surveillance coronary angiograms for CAV diagnosis.

Funding Acknowledgement

Type of funding sources: Other. Main funding source(s): Sociedad Madrileña de Trasplantes

Infective endocarditis after transcatheter aortic valve implantation

Introduction

Infective endocarditis (IE) is a potentially serious complication in patients with prosthetic heart valves. The objective of this study is to analyze and describe the incidence, baseline characteristics, risks factors and in-hospital evolution in IE after Transcatheter Aortic Valve Implantation (IE-TAVI).

Methods

All the TAVI implanted in our center since the beginning of the program have been included consecutively. Patients with a confirmed diagnosis of IE according to the “ESC Guidelines for the management of infective endocarditis” are identified and analyzed.

Results

331 TAVI have been implanted in our center from June 2009 to February 2021. IE-TAVI incidence in our series is 2.7% (n=9 cases). In baseline analysis, we observed that insulin dependent diabetes mellitus, Barthel Score and Pulmonary systolic pressure >50mmHg are significantly associated with the appearance of IE-TAVI (TABLE 1).

The most frequently microorganism is Enterococcus faecalis (44.4%; n=4) followed by Staphylococcus aureus (22.2%; n=2), Coagulase-negative staphylococci (22.2%; n=2) and Streptococcus viridans (11.1%; n=1).

77.8% of IE-TAVI (n=7) are Nosocomial IE or non-nosocomial healthcare-associated IE. 2 of them have been related to implantation (1 Enterococcus faecalis and 1 Coagulase-negative staphylococci) and 5 have been related to other interventions (2 after gastroscopy, 1 after percutaneous vascular intervention, 1 hemodialysis catheter infection and 2 unknown focus).

44.4% of IE-TAVI (n=4) were confirmed after performing Positron Emission Tomography (PET) scan. 3 cases (33.3%) were diagnosed with the initial Transthoracic Echocardiogram (TTE) and 2 cases (22.2%) were diagnosed after performing a Transesophageal Echocardiogram (TEE) (TABLE 2)

4 patients had an indication for surgery according to the ESC Guidelines (3 for persistent bacteremia and 1 for severe aortic regurgitation), but all were ruled out due to high surgical risk. Hospital mortality was 44.4% (n=4). The main predictor of hospital mortality was having an indication for surgery (p=0.028), which was present in 3 of the 4 deaths. The other death was due to digestive bleeding during hospitalization.

Conclusions

IE-TAVI is a serious disease with high in-hospital mortality. Insulin dependent diabetes mellitus, Barthel Score and Pulmonary systolic pressure >50mmHg are risk factors for IE-TAVI. PET-scan is the imaging test of choice when there were no echocardiographic findings. The main predictor of mortality is having an indication for surgery according to the ESC Guidelines.

Funding Acknowledgement

Type of funding sources: None.

Clinical outcomes of percutaneous coronary intervention in coronary allograft vasculopathy from single center experience

Background/Introduction

Cardiac allograft vasculopathy (CAV) is a leading cause of morbidity and mortality of heart transplant recipients. Percutaneous coronary intervention (PCI) is an alternative to medical treatment, however long-term data from large multicenter studies are scarce.

Purpose

To review clinical characteristics and outcomes of CAV undergoing PCI in our heart transplant series.

Methods

We analysed retrospectively 52 heart transplant recipients with CAV who underwent PCI from 2004 to 2020. Surveillance angiography was performed in 90% of stents. Stent restenosis (SR), stent thrombosis (ST), target lesion revascularization (TLR) and patient survival are reported.

Results

During study period, 124 lesions were treated. Primary success was obtained in 99% of lesions. Mean angiographic follow up was 37±47 months. A total of 31 (25%) stents presented events during follow-up: 24 SR, 7 ST. There were no differences between bare-metal stent (BMS) and drug-eluting stent (DES). We performed 16 (12.9%) TLR. There was no association between clinical and lesion-related features and TLR. Post-PCI survival was 75.3% at 5 and 55.7% at 10 years.. Cytomegalovirus (CMV) infection before development of CAV decreased survival in univariable analysis (p<0.016).

Conclusions

PCI with stent in CAV can be performed with high rates of primary success and low rate of complications, similar to non-transplant patients. Our series suggest that CMV infection can have negative impact in post-PCI survival, but further studies are needed.

Funding Acknowledgement

Type of funding source: None

Serum periostin is not related to asthma predictive index

BACKGROUND

In contrast to adult asthmatic patients, studies on the role of serum periostin levels in schoolchildren with asthma are still conflictive, and very few studies have been performed in pre-schoolers. The aim of this study was to compare serum periostin levels in recurrent wheezer pre-schoolers according to their asthma predictive index (API) condition.

METHODS

We performed a case-control study enrolling pre-schoolers with recurrent wheezing episodes (>3 episodes confirmed by physician) presented at one paediatric clinic in Santiago, Chile. The population was divided according to stringent API criteria into positive or negative.

RESULTS

In a one-year period, 60 pre-schoolers were enrolled. After excluding 12 (due to not fulfilment of inclusion criteria or refusal of blood sample extraction), 48 remaining pre-schoolers (27 males, age range from 24 to 71 months) completed the study; 34 were API positive and 14 were API negative. There were no significant differences in demographics between groups. The level of serum periostin levels for pre-schoolers with positive API and negative API were (median 46.7 [25.5-83.1] and 67.5 [20.5-131.8], p=0.9, respectively). The area under the curve for the serum periostin levels for predict positive API was 0.5, 95% CI [0.29-0.70], p=0.9. No significant correlation between serum periostin levels and peripheral blood eosinophils was found.

CONCLUSION

Serum periostin levels were no significantly different between wheezer pre-schoolers with positive and negative API. More studies are needed to confirm this finding.

Helicobacter pylori infection is associated with an altered gastric microbiota in children

The intestinal microbiome in early life influences development of the mucosal immune system and predisposition to certain diseases. Because less is known about the microbiome in the stomach and its relationship to disease, we characterized the microbiota in the stomachs of 86 children and adults and the impact of Helicobacter pylori infection on the bacterial communities. The overall composition of the gastric microbiota in children and adults without H. pylori infection was similar, with minor differences in only low abundance taxa. However, the gastric microbiota in H. pylori-infected children, but not infected adults, differed significantly in the proportions of multiple high abundance taxa compared with their non-infected peers. The stomachs of H. pylori-infected children also harbored more diverse microbiota, smaller abundance of Firmicutes, and larger abundance of non-Helicobacter Proteobacteria and several lower taxonomic groups than stomachs of H. pylori-infected adults. Children with restructured gastric microbiota had higher levels of FOXP3, IL10, and TGFβ expression, consistent with increased T-regulatory cell responses, compared with non-infected children and H. pylori-infected adults. The gastric commensal bacteria in children are altered during H. pylori infection in parallel with more tolerogenic gastric mucosae, potentially contributing to the reduced gastric disease characteristic of H. pylori-infected children.