Chamberlain Papers Highlight Impactful Research

Quality standards for lung cancer surgery, optimal timing between myocardial infarction (MI) and coronary artery bypass grafting (CABG) surgery, and initial results from the bifurcated Y-graft Fontan procedure are featured in three of the most important scientific abstracts accepted to the STS 52nd Annual Meeting program.

Each year, the J. Maxwell Chamberlain Memorial Papers kick off the meeting’s scientific sessions and honor Dr. Chamberlain, who has been called “the most important influence in the formation of The Society of Thoracic Surgeons.” Don’t miss the 2016 presentations, which begin at 7:15 a.m. this morning in Exhibit Halls 2-3 as part of the General Session.

Most Centers Miss Key Lung Cancer Surgery Quality Indicators

Many lung cancer patients may not receive optimal surgical care. New research shows that the vast majority of institutions meet one or two quality standards for the surgical treatment of stage 1 non-small-cell lung cancer, but few institutions meet four key indicators.

Pamela P. Samson, MD

“We found that meeting all four quality measures decreased a patient’s risk of mortality by 60%,” said lead author Pamela P. Samson, MD, General Surgery Resident at Washington University School of Medicine in St. Louis. “Many patients were meeting at least two quality measures during our study years of 2004 to 2013. However, when we looked at the number of patients meeting all four quality measures in the treatment of their stage 1 non-small-cell lung cancer (NSCLC), only 22.5% received what could be called optimal care. The bar needs to be raised, especially when meeting it conveys such a significant survival advantage for patients.”

On behalf of Dr. Samson, Varun Puri, MD, senior author of the study and Associate Professor of Surgery at Washington University, will present the 2016 J. Maxwell Chamberlain Memorial Paper for General Thoracic Surgery, “Quality Measures in Clinical State 1 Non-Small-Cell Lung Cancer: Improved Performance in Associated With Improved Survival.” The study was based on 146,908 surgeries for clinical stage I NSCLCs abstracted from the National Cancer Data Base (NCDB).

Surgeries were evaluated on four quality measures established by STS, the National Comprehensive Cancer Network, the American College of Surgeons Commission on Cancer, and American College of Chest Physician guidelines. The measures included performing an anatomical lung resection, surgery within 8 weeks of diagnosis, achieving an R0 resection, and pathologic evaluation of 10 or more lymph nodes. Socioeconomic factors were associated with a greater likelihood of receiving all four quality measures, as was receiving care at an academic medical center, Dr. Samson said.

“We hope that when attendees see these results, they will think about their own institutions and practices and find ways to help more patients meet these quality measures,” Dr. Samson said. “For example, at our own institution, many patients received delayed surgery by this criteria, and we are actively working to improve that. Nationally, we also are concerned with increasing lymph node sampling and decreasing the significant number of patients who are still getting wedge resections, which are seen as oncologically inferior surgeries for lung cancer. These gaps are not evident until you probe national databases, like the NCDB, your own institutional database, and practice patterns. Therefore, we believe this study can be a starting point for the discussion both nationally and locally to improve surgical quality and patient survival.”

Study Suggests Reducing MI to Surgery Timing

The second Chamberlain paper being presented this morning generally supports current trends toward reducing the waiting time between MI and CABG surgery. An analysis of data from 3,060 CABG patients within the Northern New England Cardiovascular Disease Study Group Cardiac Surgery Registry found no difference in either crude or adjusted mortality rates in patients operated on 1-2 days, 3-7 days, or 8-21 days after MI. Patients operated on in <1 day had significantly higher mortality compared to those operated on 3-7 days after MI. Patients who received their CABG 8-21 days after MI had more comorbidities and slightly higher mortality.

Elizabeth L. Nichols, MS

“The timing between MI and CABG has been debated for a long time, but there are few data on outcomes with multiple discrete timing intervals of surgery,” said lead author Elizabeth L. Nichols, MS, a PhD candidate at The Dartmouth Institute in Lebanon, N.H. “These results help inform how to provide the best quality care for our patients, while not adding any unnecessary wait times between MI and surgery.”

The Chamberlain Paper for Adult Cardiac Surgery, “Optimal Timing Between Myocardial Infarction and Coronary Artery Bypass Grafting: Impact on In-Hospital Mortality,” compared in-hospital mortality rates. The study excluded emergency and shock patients, as well as patients operated on less than 6 hours following their MI, to create a more uniform cohort.

In-hospital mortality was highest in patients operated on less than 1 day after MI. There was no difference in mortality for surgeries performed 1-2 days and 3-7 days after MI, and a non-significant increase was seen in mortality for surgeries performed 8-21 days after MI.

“We would like to see more data, as always,” Nichols said, “and we would like clinicians to be mindful about how long they wait between MI and CABG. For patients who are stable, we may not have to wait 5 days but can consider operating earlier, while it may be worth waiting for high-risk patients.”

Early Results Are Positive for Bifurcated Y-Graft Fontan Procedure

Initial clinical results suggest that the latest revision of the Fontan procedure using a bifurcated Y-graft is safe and produces reasonable results. The new procedure is based on computer modeling that predicts improved flow dynamics by directing the inferior vena caval flow to the right and left pulmonary arteries using separate graft limbs.

Kirk R. Kanter, MD

The Chamberlain Paper for Congenital Heart Surgery, “Clinical Experience With the Bifurcated Y-Graft Fontan Procedure,” recounts the experience with a heterogeneous group of children operated on between August 2010 and May 2015. Early pleural effusions were common, but there were no long-term recurrences, said lead author Kirk R. Kanter, MD, Professor of Surgery at Emory University School of Medicine in Atlanta. There were two deaths in the group, one from ongoing liver failure in a patient with preoperative liver dysfunction and one relentless heart failure.

“Computer modeling predicts that a Y-graft is more energy efficient than the straight tube procedure that is usually used,” Kanter said. “We have followed 45 children for just over 2 years and have found that it is a safe procedure and not inferior to the standard Fontan. This is a slightly bigger operation and may not be necessary for everyone, but there are certainly patients for whom it is better.”