Pulmonary Valve Replacement in Tetralogy of Fallot: Procedural Volume and Durability of Bioprosthetic Pulmonary Valves

BACKGROUND

Robust data on changes in pulmonary valve replacement (PVR) procedural volume and predictors of bioprosthetic pulmonary valve (BPV) durability in patients with tetralogy of Fallot (TOF) are scarce.

OBJECTIVES

This study sought to assess temporal trends in PVR procedural volume and BPV durability in a nationwide, retrospective TOF cohort.

METHODS

Data were obtained from patient records. Robust linear regression was used to assess temporal trends in PVR procedural volume. Piecewise exponential additive mixed models were used to estimate BPV durability, defined as the time from implantation to redo PVR with death as a competing risk, and to assess risk factors for reduced durability.

RESULTS

In total, 546 PVR were performed in 384 patients from 1976 to 2021. The annual number of PVR increased from 0.4 to 6.0 per million population (P < 0.001). In the last decade, the transcatheter PVR volume increased by 20% annually (P < 0.001), whereas the surgical PVR volume did not change significantly. The median BPV durability was 17 years (Q1: 10-Q3: 10 years-not applicable). There was no significant difference in the durability of different BPV after adjustment for confounders. Age at PVR (HR: 0.78 per 10 years from <1 year; 95% CI: 0.63-0.96; P = 0.02) and true inner valve diameter (9-17 mm vs 18-22 mm HR: 0.40; 95% CI: 0.22-0.73; P = 0.003 and 18-22 mm vs 23-30 mm HR: 0.59; 95% CI: 0.25-1.39; P = 0.23) were associated with reduced BPV durability in multivariate models.

CONCLUSIONS

The PVR procedural volume has increased over time, with a greater increment in transcatheter than surgical PVR during the last decade. Younger patient age at PVR and a smaller true inner valve diameter predicted reduced BPV durability.

Cardiac Reoperation or Transcatheter Mitral Valve Replacement for Patients With Failed Mitral Prostheses

BACKGROUND

Evidence is limited regarding patient outcomes comparing redo surgical mitral valve replacement (redo SMVR) vs transcatheter mitral valve replacement (TMVR) for failed prostheses.

OBJECTIVES

The goal of this study was to compare the outcomes of redo SMVR vs TMVR in patients with failed prostheses, as well as evaluate the association between case volume and outcomes.

METHODS

Medicare beneficiaries aged ≥65 years who underwent redo SMVR or TMVR for failed mitral prostheses between 2016 and 2020 were included. The primary endpoint was mid-term (up to 3 years) major adverse cardiovascular events (MACE), including all-cause death, heart failure rehospitalization, stroke, or reintervention. Propensity score-matched analysis was used.

RESULTS

A total of 4,293 patients were included (redo SMVR: 64%; TMVR: 36%). TMVR recipients were older, with a higher comorbidity burden. In matched cohort (n = 1,317 in each group), mid-term risk of MACE was similar (adjusted HR: 0.92; 95% CI: 0.80-1.04; P = 0.2). However, landmark analysis revealed a lower risk of MACE with TMVR in the first 6 months (adjusted HR: 0.75; 95% CI: 0.63-0.88; P < 0.001) albeit with a higher risk beyond 6 months (adjusted HR: 1.28; 95% CI: 1.04-1.58; P = 0.02). Increasing procedural volume was associated with decreased risk of mid-term MACE after redo SMVR (P = 0.001) but not after TMVR (P = 0.3).

CONCLUSIONS

In this large cohort of Medicare beneficiaries with failed mitral prostheses, outcomes were similar between redo SMVR and TMVR at 3 years, with TMVR showing a lower initial risk but a higher risk of MACE after 6 months. These findings highlight the importance of striking a balance between surgical risk, anticipated longevity, and hospital expertise when selecting interventions.

Annual hospital procedural volume and outcome in extracorporeal membrane oxygenation for respiratory failure

BACKGROUND

The hospital mortality of patients suffering from pulmonary failure requiring venovenous extracorporeal membrane oxygenation (V-V ECMO) or extracorporeal carbon dioxide removal (ECCO₂ R) is high. It is unclear whether outcome correlates with a hospital's annual procedural volume.

METHODS

Data on all V-V ECMO and ECCO₂ R cases treated from 2007 to 2019 was retrieved from the German Institute for Medical Documentation and Information. Comorbidities and outcomes were assessed by DRG, OPS, and ICD codes. The study population was divided into 5 groups depending on annual hospital V-V ECMO and ECCO₂ R volumes (<10 cases; 10-19 cases; 20-29 cases; 30-49 cases; ≥50 cases). Primary outcome was hospital mortality.

RESULTS

A total of 25,096 V-V ECMO and 3,607 ECCO₂ R cases were analyzed. V-V ECMO hospitals increased from 89 in 2007 to 214 in 2019. Hospitals handling <10 cases annually increased especially (64 in 2007 to 149 in 2019). V-V ECMO cases rose from 807 in 2007 to 2,597 in 2019. Over 50% were treated in hospitals handling ≥30 cases annually. Hospital mortality was independent of the annual hospital procedural volume (55.3%; 61.3%; 59.8%; 60.2%; 56.3%, respectively, p=0.287). We detected no differences when comparing hospitals handling <30 cases to those with ≥30 annually (p=0.659). The numbers of ECCO₂ R hospitals and cases has dropped since 2011 (287 in 2007 to 48 in 2019). No correlation between annual hospital procedural volume and hospital mortality was identified (p=0.914).

CONCLUSION

The number of hospitals treating patients requiring V-V ECMO and V-V ECMO cases rose from 2007 to 2019, while ECCO₂ R hospitals and their case numbers decreased. We detected no correlation between annual hospital V-V ECMO or ECCO₂ R volume and hospital mortality.

The Bigger the Better? Center Volume Dependent Effects on Procedural and Functional Outcome in Established Endovascular Stroke Centers

Background

Mechanical thrombectomy (MT) rates for the treatment of acute ischaemic stroke due to large vessel occlusion are steadily increasing, but are delivered in heterogenic settings. We aim to investigate effects of procedural load in centers with established MT-structures by comparing high- vs. low-volume centers with regard to procedural characteristics and functional outcomes.

Methods

Data from 5,379 patients enrolled in the German Stroke Registry Endovascular Treatment (GSR-ET) between June 2015 and December 2019 were compared between three groups: high volume: ≥180 MTs/year, 2,342 patients; medium volume: 135-179 MTs/year, 2,202 patients; low volume: <135 MTs/year, 835 patients. Univariate analysis and multiple linear and logistic regression analyses were performed to identify differences between high- and low-volume centers.

Results

We identified high- vs. low-volume centers to be an independent predictor of shorter intra-hospital (admission to groin puncture: 60 vs. 82 min, β = -26.458; p < 0.001) and procedural times (groin puncture to flow restoration: 36 vs. 46.5 min; β = -12.452; p < 0.001) after adjusting for clinically relevant factors. Moreover, high-volume centers predicted a shorter duration of hospital stay (8 vs. 9 days; β = -2.901; p < 0.001) and favorable medical facility at discharge [transfer to neurorehabilitation facility/home vs. hospital/nursing home/in-house fatality, odds ratio (OR) 1.340, p = 0.002]. Differences for functional outcome at 90-day follow-up were observed only on univariate level in the subgroup of primarily to MT center admitted patients (mRS 0-2 38.5 vs. 32.8%, p = 0.028), but did not persist in multivariate analyses.

Conclusion

Differences in efficiency measured by procedural times call for analysis and optimization of in-house procedural workflows at regularly used but comparatively low procedural volume MT centers.

Impact of Hospital Procedural Volume on Outcomes After Endovascular Revascularization for Critical Limb Ischemia

OBJECTIVES

The aim of this study was to evaluate the interaction between hospital endovascular lower extremity revascularization (eLER) volume and outcomes after eLER for critical limb ischemia (CLI).

BACKGROUND

There is a paucity of data on the relationship between hospital procedural volume and outcomes of eLER for CLI.

METHODS

The authors queried the Nationwide Readmission Database (2013-2015) for hospitalized patients who underwent eLER for CLI. Hospitals were divided into tertiles according to annual eLER volume: low volume (<100 eLER procedures), moderate volume (100-550 eLER procedures), and high volume (>550 eLER procedures). Stepwise multivariable regression models were used. The main outcomes were in-hospital mortality and 30-day readmission with major adverse limb events, defined as the composite of amputation, acute limb ischemia, or repeat revascularization.

RESULTS

Among 145,785 hospitalizations for eLER for CLI, 5,199 (3.6%) were at low-volume eLER hospitals, 27,857 (19.1%) at moderate-volume eLER hospitals, and 112,728 (77.3%) at high-volume eLER hospitals. On multivariable analysis, there was no difference with regard to in-hospital mortality among moderate-volume hospitals (adjusted odds ratio [OR]: 0.78; 95% CI: 0.60-1.01) and high-volume hospitals (adjusted OR: 0.84; 95% CI: 0.64-1.05) compared with low-volume hospitals. There was lower risk of in-hospital major amputation (adjusted OR: 0.82; 95% CI: 0.70-0.96) and minor amputation at high- versus low-volume hospitals. The length of hospital stay was shorter and discharges to nursing facilities were fewer among moderate- and high-volume hospitals compared with low-volume hospitals. Compared with low-volume hospitals, eLER for CLI at high-volume hospitals had a lower risk for 30-day readmission with major adverse limb events (adjusted OR: 0.83; 95% CI: 0.70-0.99), while there was no difference among moderate-volume hospitals (adjusted OR: 0.92; 95% CI: 0.77-1.10).

CONCLUSIONS

This nationwide observational analysis suggests that annual eLER volume does not influence in-hospital mortality after eLER for CLI. However, high eLER volume (>550 eLER procedures) was associated with better rates of limb preservation after eLER for CLI.

Mitral valve repair rates in degenerative mitral valve disease correlate with surgeon and hospital procedural volume

STUDY AIM

To determine the relationship between surgeon and hospital procedural volume, and mitral valve repair rates and 30-day mortality for degenerative mitral regurgitation (MR), in Australian cardiac surgical centers.

METHODS

A total of 4420 patients who underwent elective surgery for degenerative MR between January 2008 and December 2017 in the Australian and New Zealand Society of Cardiac and Thoracic Surgeons Database were retrospectively included. Univariate and multivariate regression analyses examined surgeon and hospital procedural volumes for associations with repair rate and mortality.

RESULTS

Repair rates varied widely by caseload; from 62.57% to 79.53% for lowest to highest volume surgeons; and from 54.56% to 77.54% for lowest to highest volume hospitals. Compared to surgeons performing ≤5 procedures/annum, surgeons performing 10.1-20/annum were more likely to repair the valve (odds ratio [OR] 2.40, 95% confidence interval [CI] 1.09-5.28, p = .03), particularly if performing more than 20/annum (OR 2.88, 95% CI 1.09-7.60, p = .03). Compared to hospitals performing ≤10/annum, those performing any number of procedures more than 10 demonstrated an increased likelihood of repair (caseload 10.1-20/year OR 1.96, 95% CI 1.25-3.07, p = .003) though odds did not increase above this threshold. Low incidence of 30-day mortality (63 of 4414, 1.43%) limited analysis of contributing variables; procedural volume did not confer a survival benefit.

CONCLUSIONS

Surgeon and hospital caseload were significantly associated with repair rates of degenerative MR. A threshold minimum of 10 procedures annually for surgeons and hospitals should be utilized to maximize repair rates, and ideally of 20 for surgeons. Mortality was low and may not be significantly impacted by procedural volume.

Impact of the COVID-19 pandemic on interventional cardiology fellowship training in the New York metropolitan area: A perspective from the United States epicenter

Background

The healthcare burden posed by the coronavirus disease 2019 (COVID‐19) pandemic in the New York Metropolitan area has necessitated the postponement of elective procedures resulting in a marked reduction in cardiac catheterization laboratory (CCL) volumes with a potential to impact interventional cardiology (IC) fellowship training.

Methods

We conducted a web‐based survey sent electronically to 21 Accreditation Council for Graduate Medical Education accredited IC fellowship program directors (PDs) and their respective fellows.

Results

Fourteen programs (67%) responded to the survey and all acknowledged a significant decrease in CCL procedural volumes. More than half of the PDs reported part of their CCL being converted to inpatient units and IC fellows being redeployed to COVID‐19 related duties. More than two‐thirds of PDs believed that the COVID‐19 pandemic would have a moderate (57%) or severe (14%) adverse impact on IC fellowship training, and 21% of the PDs expected their current fellows' average percutaneous coronary intervention (PCI) volume to be below 250. Of 25 IC fellow respondents, 95% expressed concern that the pandemic would have a moderate (72%) or severe (24%) adverse impact on their fellowship training, and nearly one‐fourth of fellows reported performing fewer than 250 PCIs as of March 1st. Finally, roughly one‐third of PDs and IC fellows felt that there should be consideration of an extension of fellowship training or a period of early career mentorship after fellowship.

Conclusions

The COVID‐19 pandemic has caused a significant reduction in CCL procedural volumes that is impacting IC fellowship training in the NY metropolitan area. These results should inform professional societies and accreditation bodies to offer tailored opportunities for remediation of affected trainees.

Operative volume and outcomes of cerebrovascular neurosurgery in children

OBJECTIVE The impact of procedural volume on the outcomes of cerebrovascular surgery in children has not been determined. In this study, the authors investigated the association of operative volume on the outcomes of cerebrovascular neurosurgery in pediatric patients. METHODS The authors performed a cohort study of all pediatric patients who underwent a cerebrovascular procedure between 2003 and 2012 and were registered in the Kids' Inpatient Database (KID). To control for confounding, the authors used multivariable regression models, propensity-score conditioning, and mixed-effects analysis to account for clustering at the hospital level. RESULTS During the study period, 1875 pediatric patients in the KID underwent cerebrovascular neurosurgery and met the inclusion criteria for the study; 204 patients (10.9%) underwent aneurysm clipping, 446 (23.8%) underwent coil insertion for an aneurysm, 827 (44.1%) underwent craniotomy for arteriovenous malformation resection, and 398 (21.2%) underwent bypass surgery for moyamoya disease. Mixed-effects multivariable regression analysis revealed that higher procedural volume was associated with fewer inpatient deaths (OR 0.58; 95% CI 0.40-0.85), a lower rate of discharges to a facility (OR 0.87; 95% CI 0.82-0.92), and shorter length of stay (adjusted difference -0.22; 95% CI -0.32 to -0.12). The results in propensity-adjusted multivariable models were robust. CONCLUSIONS In a national all-payer cohort of pediatric patients who underwent a cerebrovascular procedure, the authors found that higher procedural volume was associated with fewer deaths, a lower rate of discharges to a facility, and decreased lengths of stay. Regionalization initiatives should include directing children with such rare pathologies to a center of excellence.

Procedural volume and outcomes with radial or femoral access for coronary angiography and intervention. J Am Coll Cardiol. 2014;63:954-963. [PMID: 24269362 DOI: 10.1016/j.jacc.2013.10.052]

OBJECTIVES

The study sought to evaluate the relationship between procedural volume and outcomes with radial and femoral approach.

BACKGROUND

RIVAL (RadIal Vs. femorAL) was a randomized trial of radial versus femoral access for coronary angiography/intervention (N = 7,021), which overall did not show a difference in primary outcome of death, myocardial infarction, stroke, or non-coronary artery bypass graft major bleeding.

METHODS

In pre-specified subgroup analyses, the hazard ratios for the primary outcome were compared among centers divided by tertiles and among individual operators. A multivariable Cox proportional hazards model was used to determine the independent effect of center and operator volumes after adjusting for other variables.

RESULTS

In high-volume radial centers, the primary outcome was reduced with radial versus femoral access (hazard ratio [HR]: 0.49; 95% confidence interval [CI]: 0.28 to 0.87) but not in intermediate- (HR: 1.23; 95% CI: 0.88 to 1.72) or low-volume centers (HR: 0.83; 95% CI: 0.52 to 1.31; interaction p = 0.021). High-volume centers enrolled a higher proportion of ST-segment elevation myocardial infarction (STEMI). After adjustment for STEMI, the benefit of radial access persisted at high-volume radial centers. There was no difference in the primary outcome between radial and femoral access by operator volume: high-volume operators (HR: 0.79; 95% CI: 0.48 to 1.28), intermediate (HR: 0.87; 95% CI: 0.60 to 1.27), and low (HR: 1.10; 95% CI: 0.74 to 1.65; interaction p = 0.536). However, in a multivariable model, overall center volume and radial center volume were independently associated with the primary outcome but not femoral center volume (overall percutaneous coronary intervention volume HR: 0.92, 95% CI: 0.88 to 0.96; radial volume HR: 0.88, 95% CI: 0.80 to 0.97; and femoral volume HR: 1.00, 95% CI: 0.94 to 1.07; p = 0.98).

CONCLUSIONS

Procedural volume and expertise are important, particularly for radial percutaneous coronary intervention. (A Trial of Trans-radial Versus Trans-femoral Percutaneous Coronary Intervention [PCI] Access Site Approach in Patients With Unstable Angina or Myocardial Infarction Managed With an Invasive Strategy [RIVAL]; NCT01014273).