- In a retrospective study of 7,365 matched pairs of patients who underwent cardiac transplantation, survival was significantly reduced in patients who had a prior history of sternotomy compared with those who did not
- Subgroup analysis suggested that the difference in survival was largely explained by differences in early postoperative mortality
- Among patients with a history of prior sternotomy, those who had prior cardiac transplant had a greater risk of long term mortality than those who received a left ventricular assist device (LVAD) or had previous cardiac surgery
- In a separate matched comparison, there was no significant difference in overall survival between patients with no prior history of sternotomy and those with a history of LVAD therapy
Increasingly often, cardiac transplantation is performed in patients who have a history of cardiac surgery, which may complicate both the procedure and the postoperative course. In particular, cardiac transplants performed via a reoperative sternotomy might have poorer short- and long-term outcomes, but the evidence on this is mixed.
Many studies of this issue have had small sample sizes and reported only on single-institution experience, and few have attempted to stratify the type of previous cardiac intervention. By reviewing nationwide data, Mauricio A. Villavicencio-Theoduloz, MD, director of Lung Transplantation and ECMO in the Division of Cardiac Surgery; Gregory D. Lewis, MD, medical director of the Cardiology ICU and Mechanical Circulatory Support Program; Serguei Melnitchouk, MD, MPH, co-director of the Heart Valve Program; George Tolis, MD, cardiac surgeon; David A. D'Alessandro, MD, surgical director of Heart Transplantation and Ventricular Assist Devices, and colleagues have more definitively linked prior sternotomy to worse survival after cardiac transplantation. Their findings appear in the European Journal of Cardio-Thoracic Surgery.
The researchers collected data from the United Network for Organ Sharing on patients who received a heart transplant in the U.S. between January 2005 and June 2017. After propensity matching, 7,365 pairs of patients—one with and one without prior sternotomy—were analyzed. Of the patients who had the previous sternotomy, 32% had received a left ventricular assist device (LVAD), 6% had received a previous heart transplant and 61% had their previous cardiac operation for other reasons. The median follow-up time was four years, and 25% of patients were followed for more than seven years.
On multivariate analysis, prior sternotomy was associated with an increased risk of post-transplant mortality, both overall and according to the reason for the prior sternotomy:
- Receipt of LVAD: 19% increased risk of death
- Receipt of prior heart transplant: 68% increased risk of death
- Other reasons: 13% increased risk of death
A history of previous mediastinal radiation was associated with an 82% increased risk of death after transplant. Other risk factors were obesity, diabetes and pretransplant creatinine ≥1.4 mg/dL.
In a subgroup analysis, the researchers included only patients who survived the first year after transplant. Overall, among these patients, there was no significant difference in post-transplant survival between those with and without prior sternotomy.
It is likely that the difference in survival after cardiac transplantation with or without prior sternotomy is largely attributable to the difference in early postoperative survival and does not persist over time. The difference in early survival is likely explained by the increased technical complexity and perioperative morbidity associated with a reoperative field.
History of Mediastinal Radiation
History of mediastinal radiation was associated with the greatest risk of post-transplant mortality in the primary analysis. The researchers analyzed 31 patients with such a history. Mediastinal radiation was associated with worse long-term survival regardless of whether the patient had prior sternotomy. Patients with a history of mediastinal radiation and prior sternotomy had especially poor outcomes.
Primary Transplant vs. Transplant After LVAD
Because so many patients nowadays are bridged to transplant with an LVAD, the research group analyzed 3,384 patients without prior sternotomy and 3,384 matched patients who received an LVAD prior to cardiac transplantation. There was no significant difference between these groups in long-term survival.
The protective effects of LVAD therapy may counteract or even outweigh the risk of increased operative complexity associated with reoperative sternotomy and LVAD explantation. These findings are extremely encouraging.
Physicians and surgeons are advised to consider medication, rather than LVAD therapy, as a bridge to transplant for medically stable patients whose demographic and clinical characteristics predict shorter time on the waitlist. Such characteristics include blood type AB, female gender and body mass index under 23 kg/m2.
Learn more about cardiac surgery at Mass General
Refer a patient to the Mass General Heart Center