Cost of Thoracotomy Approach: An Analysis of the LATERAL Trial

Collection of economic data using UB-04s: Is it worth the effort? Evidence from two clinical trials

Cost collection using UB-04 forms for economic evaluation is challenging, as UB-04 collection is time and effort intensive and compliance is imperfect. Alternative data sources could overcome those challenges. The objective of this study is to determine the usefulness of UB-04 data in estimating hospital costs compared to clinical case report form (CRF) data. Health care utilization costs were compared from financial information in UB-04s and from an assignment process using CRF data, from the WRAP-IT (23 infections) and the Micra IDE trials (61 adverse events and 108 implants). Charge-based costs were calculated by multiplying charges in UB-04s and hospital-specific Cost-to-Charge ratios from the Centers for Medicare and Medicaid Services cost reports. The cost assignment process used clinical information to find comparable encounters in real world data and assigned an average cost. Paired difference tests evaluated whether both methods yield similar results. The mean difference in total infection related costs between methods in the WRAP-IT trial was $152 +/-$22,565. In the Micra IDE trial, the mean difference in total adverse event related costs between methods was -$355 +/-$8,298 while the mean difference in total implant related costs between methods was $-3,488 +/-$13,859. Wilcoxon tests and generalized linear models could not reject the difference in costs between methods in the first two cases. Cost assignment methods achieve results similar to costs obtained through UB-04s, without the additional investment in time and effort. The use of UB-04 information for services that are not mature in a health care system may present unexpected challenges, necessitating a tradeoff with other methods of cost assignment.

Sternum-Sparing Left Ventricular Assist Device Insertion Reduces Perioperative Transfusions and Blood Loss: A Single-Centre Canadian Experience

Background

Left ventricular assist devices (LVADs) improve survival and quality of life, as either destination therapy or a bridge to transplantation. Although less-invasive hemisternotomy approaches for LVAD implantation are well studied, only a paucity of data is available in the literature on sternum-sparing bilateral minithoracotomy (BMT). Our centre has one of Canada’s most extensive experiences with the BMT approach. Herein, we compared LVAD implantation via BMT with patients who received full median sternotomy or hemisternotomy.

Methods

A single-centre retrospective review of data from Foothills Medical Centre (Calgary, Canada) was performed. Patients underwent LVAD insertion from 2012 to 2019, receiving either BMT (n = 11) or sternotomy (full median sternotomy or upper hemisternotomy with left minithoracotomy; n = 38). Intraoperative and early postoperative outcomes were assessed.

Results

Patients who received BMT had significantly fewer transfusions of red blood cells, fresh frozen plasma, and platelets. The BMT group had lower chest-tube output in the first 12 hours. No significant differences occurred in ventilation time, intensive care unit length of stay, mortality, stroke, or reoperation for bleeding.

Conclusions

Outcomes suggest that sternum-sparing LVAD implantation is a feasible alternative to sternotomy, leading to less postoperative blood loss and transfusion in the early postoperative period. Less transfusion is particularly valuable in this patient population, to reduce antigen-related sensitization prior to transplantation. Additional study is needed to assess potential benefits related to right heart function, postoperative mobility, and re-entry for transplantation.

Impact of thoracotomy approach on right ventricular failure and length of stay in left ventricular assist device implants: an intermacs registry analysis

INTRODUCTION

Traditionally, implantation of Left Ventricular Assist Devices (LVADs) is performed via median sternotomy. Recently, less invasive thoracotomy approaches are growing in popularity as they involve less surgical trauma, potentially less bleeding, and may preserve right ventricular function. We hypothesized implantation of LVADs via thoracotomy has less perioperative right ventricular failure (RVF) and shorter postoperative length of stay (LOS).

METHODS

Continuous flow LVAD implants from Intermacs between February 6, 2014 - December 31, 2018 were identified. Patients implanted via thoracotomy were propensity matched in a 1:1 ratio with patients implanted via sternotomy. Outcomes were compared between sternotomy and thoracotomy approach and by device type (axial, centrifugal-flow with hybrid levitation (CF-HL), centrifugal-flow with full magnetic levitation devices (CF-FML)). The primary outcome was time to first moderate or severe RVF. Secondary outcomes included survival and LOS.

RESULTS

Overall 978 thoracotomy patients were matched with 978 sternotomy patients. Over the study period, 242 thoracotomy patients and 219 sternotomy patients developed RVF with no significant difference in time to first moderate to severe RVF by surgical approach overall (p = 0.27) or within CF-HL (p = 0.36) or CF-FML devices (p = 0.25). Survival did not differ by implant technique (150 deaths in thoracotomy group, 154 deaths in sternotomy group; p = 0.58). However, sternotomy approach was associated with a significantly shorter LOS (17 Vs 18 days, p = 0.009).

CONCLUSION

As compared to sternotomy, implantation of continuous flow LVADs via thoracotomy approach does not reduce moderate to severe RVF or improve survival but does reduce post-operative LOS. Device type did not influence outcomes and most centers did a small volume of thoracotomy implants.

Sex differences in outcomes following less-invasive left ventricular assist device implantation

Background

Worse outcomes in women compared to men undergoing left ventricular assist device (LVAD) implantation remain an underestimated problem in heart failure (HF) patients. With device miniaturization, less-invasive LVAD implantation techniques have gained relevance, but their impact on outcomes in women is unknown. This study investigates sex-related differences in patients undergoing LVAD implantation through less-invasive procedures.

Methods

This retrospective single-center cohort study included patients who underwent isolated LVAD implantation between 2011 and 2018 through less-invasive techniques. Propensity score matching (PSM) was utilized to balance preoperative heterogeneity. Primary endpoint was two-year survival, and secondary endpoints included long-term survival, surgical outcomes and postoperative adverse events.

Results

Baseline analysis of 191 patients (females 18.3%) showed differences in terms of age [female (median, 52; IQR, 47-61); male (median, 58.5; IQR, 49-66); P=0.005], underlying diagnosis (P<0.001), INTERMACS profile (P=0.009), history of previous cardiac surgery (P=0.049) and preoperative creatinine values [female (median, 110; IQR, 71-146); male (median, 126; IQR, 9-168); P=0.049]. Over a follow-up of 460.68 patient-years, Kaplan-Meyer analysis showed better survival in females (P=0.027) and a similar probability of cardiac transplantation (P=0.288). After PSM, females showed higher needs for intraoperative fresh frozen plasma (P=0.044) and platelets (P=0.001) but comparable postoperative outcomes. No sex-related differences were noticed regarding two-year outcomes, long-term survival and adverse events. LVAD-related infections remained the most common complication with males experiencing more pump infections than women (P=0.050).

Conclusions

Patients receiving less-invasive LVAD implantation do not show significant sex-related differences in short and long-term outcomes and survival. Prospective studies are needed to evaluate the role of less-invasive techniques in reducing sex-based disparities after LVAD implantation.

Lateral Thoracotomy for Ventricular Assist Device Implantation: A Meta-Analysis of Literature

The use of lateral thoracotomy (LT) for implanting left ventricular assist devices (LVADs) is worldwide increasing, although the available evidence for its positive effects compared with conventional sternotomy (CS) is limited. This systematic review and meta-analysis analyzes the outcomes of LT compared with CS in patients undergoing implantation of a centrifugal continuous-flow LVAD. Four databases and 1,053 publications were screened until December 2019. Articles including patients undergoing implantation of a centrifugal continuous-flow LVAD through LT were included. A meta-analysis to compare LT and CS was performed to summarize evidences from studies including both LT and CS patients extracted from the same population. Primary outcome measure was in-hospital or 30-day mortality. Eight studies reporting on 730 patients undergoing LVAD implantation through LT (n = 242) or CS (n = 488) were included in the meta-analysis. Left thoracotomy showed lower in-hospital/30-day mortality (odds ratio [OR]: 0.520, 95% confidence interval [CI]: 0.27-0.99, p = 0.050), shorter intensive care unit (ICU) stay (mean difference [MD]: 3.29, CI: 1.76-4.82, p < 0.001), lower incidence of severe right heart failure (OR: 0.41; CI: 0.19-0.87, p = 0.020) and postoperative right ventricular assist device (RVAD) implantation (OR: 0.27, CI: 0.10-0.76, p = 0.010), fewer perioperative transfusions (MD: 0.75, CI: 0.36-1.14, p < 0.001), and lower incidence of renal failure (OR: 0.45, CI: 0.20-1.01, p = 0.050) and device-related infections (OR: 0.45, CI: 0.20-1.01, p = 0.050), respectively. This meta-analysis demonstrates that implantation of a centrifugal continuous-flow LVAD system via LT benefits from higher short-term survival, less right heart failure, lower postoperative RVAD need, shorter ICU stay, less transfusions, lower risk of device-related infections and kidney failure. Prospective studies are needed for further proof.

Expert Consensus Paper: Lateral Thoracotomy for Centrifugal Ventricular Assist Device Implant

BACKGROUND

The increasing prevalence of heart failure has led to the expanded use of left ventricle assist devices (VADs) for end-stage heart failure patients worldwide. Technological improvements witnessed the development of miniaturized VADs and their implantation through less traumatic non-full sternotomy approaches using a lateral thoracotomy (LT). Although adoption of the LT approach is steadily growing, a lack of consensus remains regarding patient selection, details of the surgical technique, and perioperative management. Furthermore, the current literature does not offer prospective randomized studies or evidence-based guidelines for LT-VAD implantation.

METHODS

A worldwide group of LT-VAD experts was convened to discuss these key topics openly. After a PubMed search and review with all authors, a consensus was reached and an expert consensus paper on LT-VAD implantation was developed.

RESULTS

This document aims to guide clinicians in the selection of patients suitable for LT approaches and preoperative optimization. Details of operative techniques are described, with an overview of hemisternotomy and bilateral thoracotomy approaches. A review of the best surgical practices for placement of the pump, inflow cannula, and outflow graft provides advice on the best surgical strategies to avoid device malpositioning while optimizing VAD function. Experts' opinions on cardiopulmonary bypass, postoperative management, and approaches for pump exchange and explant are presented. This review also emphasizes the critical need for multidisciplinary teams and specific training.

CONCLUSIONS

This expert consensus review provides a compact guide to LT for VAD implantation, from patient selection through intraoperative tips and postoperative management.