Institutional volume and the effect of recipient risk on short-term mortality after orthotopic heart transplant

George J. Arnaoutakis, Timothy J. George, Jeremiah G. Allen, Stuart D. Russell, Ashish S. Shah, John Conte, Eric S. Weiss

Research output: Contribution to journalArticle

38 Citations (Scopus)

Abstract

Objective: We developed a validated 50-point recipient risk index predicting short-term mortality after orthotopic heart transplant (OHT). This study examined the relationship between institutional volume and recipient risk on post-OHT mortality. Methods: We used United Network for Organ Sharing (UNOS) data to identify primary OHT recipients between January 2000 and April 2010. Centers were stratified by mean annual volume. Preoperative Index for Mortality Prediction After Cardiac Transplantation risk scores were calculated for each patient with our validated 50-point system. Primary outcomes were 30-day and 1-year survivals. Multivariable logistic regression analysis included interaction terms to examine effect modification of risk and volume on mortality. Results: In all, 18,226 patients underwent transplant at 141 centers: 1173 (6.4%) recipients at low-volume centers (<7 procedures/y), 5353 (29.4%) at medium-volume centers (7-15 procedures/y), and 11,700 (64.2%) at high-volume centers (>15 procedures/y). Low center volume was associated with worse 1-year mortality (odds ratio, 1.58; 95% confidence interval, 1.30-1.92; P < .001). For 1-year survival, there was significant positive interaction between center volume and recipient risk score (odds ratio, 1.04; 95% confidence interval, 1.01-1.07; P = .02), indicating effect of risk on mortality at low-volume centers greater than from either variable analyzed individually. Among high-risk recipients (score ≥10), 1-year survival was improved at high-volume centers (high, 79%; medium, 75%; low, 64%). Conclusions: In analysis of UNOS data with our validated recipient risk index, institutional volume acted as an effect modifier on association between risk and mortality. High-risk patients had higher mortality at low-volume centers; differences dissipated among lower-risk recipients. These data support a mandate for high-risk transplants at higher-volume centers.

Original languageEnglish (US)
Pages (from-to)157-167.e1
JournalJournal of Thoracic and Cardiovascular Surgery
Volume143
Issue number1
DOIs
StatePublished - Jan 1 2012

Fingerprint

Transplants
Mortality
Information Dissemination
Survival
Odds Ratio
Confidence Intervals
Heart Transplantation
Logistic Models
Regression Analysis

All Science Journal Classification (ASJC) codes

  • Surgery
  • Pulmonary and Respiratory Medicine
  • Cardiology and Cardiovascular Medicine

Cite this

Arnaoutakis, George J. ; George, Timothy J. ; Allen, Jeremiah G. ; Russell, Stuart D. ; Shah, Ashish S. ; Conte, John ; Weiss, Eric S. / Institutional volume and the effect of recipient risk on short-term mortality after orthotopic heart transplant. In: Journal of Thoracic and Cardiovascular Surgery. 2012 ; Vol. 143, No. 1. pp. 157-167.e1.
@article{fd9adac10ac4496fbff1801cb27c3064,
title = "Institutional volume and the effect of recipient risk on short-term mortality after orthotopic heart transplant",
abstract = "Objective: We developed a validated 50-point recipient risk index predicting short-term mortality after orthotopic heart transplant (OHT). This study examined the relationship between institutional volume and recipient risk on post-OHT mortality. Methods: We used United Network for Organ Sharing (UNOS) data to identify primary OHT recipients between January 2000 and April 2010. Centers were stratified by mean annual volume. Preoperative Index for Mortality Prediction After Cardiac Transplantation risk scores were calculated for each patient with our validated 50-point system. Primary outcomes were 30-day and 1-year survivals. Multivariable logistic regression analysis included interaction terms to examine effect modification of risk and volume on mortality. Results: In all, 18,226 patients underwent transplant at 141 centers: 1173 (6.4{\%}) recipients at low-volume centers (<7 procedures/y), 5353 (29.4{\%}) at medium-volume centers (7-15 procedures/y), and 11,700 (64.2{\%}) at high-volume centers (>15 procedures/y). Low center volume was associated with worse 1-year mortality (odds ratio, 1.58; 95{\%} confidence interval, 1.30-1.92; P < .001). For 1-year survival, there was significant positive interaction between center volume and recipient risk score (odds ratio, 1.04; 95{\%} confidence interval, 1.01-1.07; P = .02), indicating effect of risk on mortality at low-volume centers greater than from either variable analyzed individually. Among high-risk recipients (score ≥10), 1-year survival was improved at high-volume centers (high, 79{\%}; medium, 75{\%}; low, 64{\%}). Conclusions: In analysis of UNOS data with our validated recipient risk index, institutional volume acted as an effect modifier on association between risk and mortality. High-risk patients had higher mortality at low-volume centers; differences dissipated among lower-risk recipients. These data support a mandate for high-risk transplants at higher-volume centers.",
author = "Arnaoutakis, {George J.} and George, {Timothy J.} and Allen, {Jeremiah G.} and Russell, {Stuart D.} and Shah, {Ashish S.} and John Conte and Weiss, {Eric S.}",
year = "2012",
month = "1",
day = "1",
doi = "10.1016/j.jtcvs.2011.09.040",
language = "English (US)",
volume = "143",
pages = "157--167.e1",
journal = "Journal of Thoracic and Cardiovascular Surgery",
issn = "0022-5223",
publisher = "Mosby Inc.",
number = "1",

}

Institutional volume and the effect of recipient risk on short-term mortality after orthotopic heart transplant. / Arnaoutakis, George J.; George, Timothy J.; Allen, Jeremiah G.; Russell, Stuart D.; Shah, Ashish S.; Conte, John; Weiss, Eric S.

In: Journal of Thoracic and Cardiovascular Surgery, Vol. 143, No. 1, 01.01.2012, p. 157-167.e1.

Research output: Contribution to journalArticle

TY - JOUR

T1 - Institutional volume and the effect of recipient risk on short-term mortality after orthotopic heart transplant

AU - Arnaoutakis, George J.

AU - George, Timothy J.

AU - Allen, Jeremiah G.

AU - Russell, Stuart D.

AU - Shah, Ashish S.

AU - Conte, John

AU - Weiss, Eric S.

PY - 2012/1/1

Y1 - 2012/1/1

N2 - Objective: We developed a validated 50-point recipient risk index predicting short-term mortality after orthotopic heart transplant (OHT). This study examined the relationship between institutional volume and recipient risk on post-OHT mortality. Methods: We used United Network for Organ Sharing (UNOS) data to identify primary OHT recipients between January 2000 and April 2010. Centers were stratified by mean annual volume. Preoperative Index for Mortality Prediction After Cardiac Transplantation risk scores were calculated for each patient with our validated 50-point system. Primary outcomes were 30-day and 1-year survivals. Multivariable logistic regression analysis included interaction terms to examine effect modification of risk and volume on mortality. Results: In all, 18,226 patients underwent transplant at 141 centers: 1173 (6.4%) recipients at low-volume centers (<7 procedures/y), 5353 (29.4%) at medium-volume centers (7-15 procedures/y), and 11,700 (64.2%) at high-volume centers (>15 procedures/y). Low center volume was associated with worse 1-year mortality (odds ratio, 1.58; 95% confidence interval, 1.30-1.92; P < .001). For 1-year survival, there was significant positive interaction between center volume and recipient risk score (odds ratio, 1.04; 95% confidence interval, 1.01-1.07; P = .02), indicating effect of risk on mortality at low-volume centers greater than from either variable analyzed individually. Among high-risk recipients (score ≥10), 1-year survival was improved at high-volume centers (high, 79%; medium, 75%; low, 64%). Conclusions: In analysis of UNOS data with our validated recipient risk index, institutional volume acted as an effect modifier on association between risk and mortality. High-risk patients had higher mortality at low-volume centers; differences dissipated among lower-risk recipients. These data support a mandate for high-risk transplants at higher-volume centers.

AB - Objective: We developed a validated 50-point recipient risk index predicting short-term mortality after orthotopic heart transplant (OHT). This study examined the relationship between institutional volume and recipient risk on post-OHT mortality. Methods: We used United Network for Organ Sharing (UNOS) data to identify primary OHT recipients between January 2000 and April 2010. Centers were stratified by mean annual volume. Preoperative Index for Mortality Prediction After Cardiac Transplantation risk scores were calculated for each patient with our validated 50-point system. Primary outcomes were 30-day and 1-year survivals. Multivariable logistic regression analysis included interaction terms to examine effect modification of risk and volume on mortality. Results: In all, 18,226 patients underwent transplant at 141 centers: 1173 (6.4%) recipients at low-volume centers (<7 procedures/y), 5353 (29.4%) at medium-volume centers (7-15 procedures/y), and 11,700 (64.2%) at high-volume centers (>15 procedures/y). Low center volume was associated with worse 1-year mortality (odds ratio, 1.58; 95% confidence interval, 1.30-1.92; P < .001). For 1-year survival, there was significant positive interaction between center volume and recipient risk score (odds ratio, 1.04; 95% confidence interval, 1.01-1.07; P = .02), indicating effect of risk on mortality at low-volume centers greater than from either variable analyzed individually. Among high-risk recipients (score ≥10), 1-year survival was improved at high-volume centers (high, 79%; medium, 75%; low, 64%). Conclusions: In analysis of UNOS data with our validated recipient risk index, institutional volume acted as an effect modifier on association between risk and mortality. High-risk patients had higher mortality at low-volume centers; differences dissipated among lower-risk recipients. These data support a mandate for high-risk transplants at higher-volume centers.

UR - http://www.scopus.com/inward/record.url?scp=83455164045&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=83455164045&partnerID=8YFLogxK

U2 - 10.1016/j.jtcvs.2011.09.040

DO - 10.1016/j.jtcvs.2011.09.040

M3 - Article

VL - 143

SP - 157-167.e1

JO - Journal of Thoracic and Cardiovascular Surgery

JF - Journal of Thoracic and Cardiovascular Surgery

SN - 0022-5223

IS - 1

ER -