Transcatheter pulmonic valve implantation: Techniques, current roles, and future implications

Right ventricular outflow tract (RVOT) obstruction is present in a variety of congenital heart disease states including tetralogy of Fallot, pulmonary atresia/stenosis and other conotruncal abnormalities etc. After surgical repair, these patients develop RVOT residual abnormalities of pulmonic stenosis and/or insufficiency of their native outflow tract or right ventricle to pulmonary artery conduit. There are also sequelae of other surgeries like the Ross operation for aortic valve disease that lead to right ventricle to pulmonary artery conduit dysfunction. Surgical pulmonic valve replacement (SPVR) has been the mainstay for these patients and is considered standard of care. Transcatheter pulmonic valve implantation (TPVI) was first reported in 2000 and has made strides as a comparable alternative to SPVR, being approved in the United States in 2010. We provide a comprehensive review in this space–indications for TPVI, detailed procedural facets and up-to-date review of the literature regarding outcomes of TPVI. TPVI has been shown to have favorable medium-term outcomes free of re-interventions especially after the adoption of the practice of pre-stenting the RVOT. Procedural mortality and complications are uncommon. With more experience, recognition of risk of dreaded outcomes like coronary compression has improved. Also, conduit rupture is increasingly being managed with transcatheter tools. Questions over endocarditis risk still prevail in the TPVI population. Head-to-head comparisons to SPVR are still limited but available data suggests equivalence. We also discuss newer valve technologies that have limited data currently and may have more applicability for treatment of native dysfunctional RVOT substrates.

Systematic review and meta-analysis of outcomes of anatomic repair in congenitally corrected transposition of great arteries

BACKGROUND

Treatment of congenitally corrected transposition of great arteries (cc-TGA) with anatomic repair strategy has been considered superior due to restoration of the morphologic left ventricle in the systemic circulation. However, data on long term outcomes are limited to single center reports and include small sample sizes.

AIM

To perform a systematic review and meta-analysis for observational studies reporting outcomes on anatomic repair for cc-TGA.

METHODS

MEDLINE and Scopus databases were queried using predefined criteria for reports published till December 31, 2017. Studies reporting anatomic repair of minimum 5 cc-TGA patients with at least a 2 year follow up were included. Meta-analysis was performed using Comprehensive meta-analysis v3.0 software.

RESULTS

Eight hundred and ninety-five patients underwent anatomic repair with a pooled follow-up of 5457.2 patient-years (PY). Pooled estimate for operative mortality was 8.3% [95% confidence interval (CI): 6.0%-11.4%]. 0.2% (CI: 0.1%-0.4%) patients required mechanical circulatory support postoperatively and 1.7% (CI: 1.1%-2.4%) developed post-operative atrioventricular block requiring a pacemaker. Patients surviving initial surgery had a transplant free survival of 92.5% (CI: 89.5%-95.4%) per 100 PY and a low rate of need for pacemaker (0.3/100 PY; CI: 0.1-0.4). 84.7% patients (CI: 79.6%-89.9%) were found to be in New York Heart Association (NYHA) functional class I or II after 100 PY follow up. Total re-intervention rate was 5.3 per 100 PY (CI: 3.8-6.8).

CONCLUSION

Operative mortality with anatomic repair strategy for cc-TGA is high. Despite that, transplant free survival after anatomic repair for cc-TGA patients is highly favorable. Majority of patients maintain NYHA I/II functional class. However, monitoring for burden of re-interventions specific for operation type is very essential.

Comparison of Transcatheter Pulmonic Valve Implantation With Surgical Pulmonic Valve Replacement in Adults (from the National Inpatient Survey Dataset)

There are no large reports of comparative outcomes of transcatheter pulmonic valve implantation (TPVI) and surgical pulmonic valve replacement (SPVR). Prospective studies are unlikely to be feasible in the future also. Thus, we utilized a large adult inpatient database to compare the two with respect to temporal trends, in hospital outcomes and costs. Data from the National Inpatient Sample database from 2003 to 2014 was analyzed to extract patients who underwent TPVI and SPVR using unique ICD 9-CM codes. In-hospital outcomes and charges were then analyzed. All charges were converted to 2018 dollars and a loss of wages analysis was performed using the Bureau of Labor Statistics published median weekly wages. A total of 8,449 and 555 SPVR and TPVI discharges were identified. 5.8% SPVR procedures were done in rural setting versus 1.8% of TPVI. Complications including in-hospital mortality (2.3 vs 0.9%; p = 0.02) were higher in SPVR group. Length of stay was significantly shorter for the TPVI group (1 vs 5 days; p <0.001), which also contributed to lower loss of wages ($1028.57 vs $6042.86; p <0.001) with similar hospital charges. In conclusion, volumes of both TPVI and SPVR are increasing across adult hospitals in the United States, reflecting an overall increase in the adult congenital heart disease population. TPVI offers improved short-term outcomes and decreased loss of wages through shorter recovery time in this real-world database analysis.

Ischemic Evaluation in Patients Presenting with Hypertensive Emergency / Urgency and Acute Systolic Heart Failure: Is Coronary Angiography Required for all?

BACKGROUND

Patients presenting with hypertensive urgency / emergency (HUE) often have systolic heart failure(SHF). Coronary angiography is routinely done for these patients to rule out obstructive coronary artery disease (Obs-CAD). We performed a retrospective study to investigate predictors of ObsCAD in this population.

METHODS

Patients who underwent angiography to investigate SHF and had hospital admission(s) for HUE in the preceding 6 months were included in the study. Chart review was performed to obtain demographic, clinical and imaging / angiographic data. A risk score was formulated based on multivariable logistic regression analysis.

RESULTS

205 patients [age 58.9 ± 14.4 years; 62.4% male; 39.5% diabetic; median EF 25% (Inter Quartile Range: 11)] were included in the study. 33.1% patients (n = 68) had obs-CAD. Patients with obs-CAD were older, diabetic, more likely to have a history of stroke, echocardiographic regional wall motion abnormalities (RWMA) while African Americans were less likely to have obs-CAD. On multivariable analysis, only non-African American race (OR: 2.18; CI: 1.08-4.4) and RWMA (OR: 5.62; CI: 2.47-12.81) remained significant predictors of obs-CAD. A risk score (RANDS) from 0 to 9 was formulated which had a c-statistic of 0.75 with a sensitivity and specificity of 84% and 53% for predicting obsCAD respectively.

CONCLUSION

Our results suggest that only a minority of patients with HUE and SHF have obs-CAD. A simple risk score may be used to stratify this population and lower risk individuals may be screened with non-invasive testing instead of invasive catheterization. These results should be validated in large registry populations.

Transcatheter Pulmonary Valve Implantation: A Comprehensive Systematic Review and Meta-Analyses of Observational Studies

BACKGROUND

Transcatheter pulmonary valve implantation is approved for the treatment of dysfunctional right ventricle to pulmonary artery conduits. However, the literature is limited because of a small patient population, and it does not reflect changing procedural practice patterns over the last decade.

METHODS AND RESULTS

A comprehensive search of Medline and Scopus databases from inception through August 31, 2016 was conducted using predefined criteria. We included studies reporting transcatheter pulmonary valve implantation in at least 5 patients with a follow-up duration of 6 months or more. In 19 eligible studies, 1044 patients underwent transcatheter pulmonary valve implantation with a pooled follow-up of 2271 person-years. Procedural success rate was 96.2% (95% confidence intervals [CI], 94.6-97.4) with a conduit rupture rate of 4.1% (95% CI, 2.5-6.8) and coronary complication rate of 1.3% (95% CI, 0.7-2.3). Incidence of reintervention was 4.4 per 100 person-years overall (95% CI, 3.0-5.9) with a marked reduction in studies reporting ≥75% prestenting (2.9 per 100 person-years [95% CI, 1.5-4.3] versus 6.5/100 person-years [95% CI, 4.6-8.5]; P<0.01). Pooled endocarditis rate was 1.4 per 100 person-years (95% CI, 0.9-2.0).

CONCLUSIONS

Our study provides favorable updated estimates of procedural and follow-up outcomes after transcatheter pulmonary valve implantation. Widespread adoption of prestenting has improved longer-term outcomes in these patients.