Postop troponin elevation, MI impact 5-year survival

SAN FRANCISCO – Postoperative troponin elevation and myocardial infarction both impact 5-year survival following vascular surgery procedures, the results of a large long-term study showed.

In fact, troponin elevation increased the hazard of death by 50% while myocardial infarction increased the hazard of death by nearly threefold, Dr. Jessica P. Simons reported at the annual meeting of the Society for Vascular Surgery. "Future studies are needed to assess the nature of this association as well as the utility of routine postoperative screening for myocardial ischemia," said Dr. Simons of the division of vascular and endovascular surgery at the University of Massachusetts, Worcester.

In a study that she presented on behalf of the Vascular Study Group of New England (VSGNE), Dr. Simons and her associates set out to determine the association of postoperative troponin elevation with long-term survival in patients undergoing vascular surgical procedures. "Postoperative myocardial infarction has been shown to impact short- and long-term mortality," she said. "In addition, troponin elevations have also been shown to negatively impact survival for a wide range of diagnoses. This has been seen in critical care medical literature and also in the general surgical population."

The researchers identified 16,363 VSGNE patients who underwent carotid revascularization, open AAA repair, endovascular AAA repair, or lower-extremity bypass between 2003 and 2011. The exposure variable of interest was postoperative myocardial ischemia, which was categorized as either no ischemia, troponin elevation, or myocardial infarction. The primary end point was survival during the first 5 years postoperatively. They used Kaplan-Meier analyses and Cox proportional hazards models to evaluate the effect of postoperative troponin elevation and myocardial infarction.

Of the 16,363 patients, 15,888 (97.1%) had no ischemia, 211 (1.3%) had troponin elevation, and 264 (1.6%) had myocardial infarction. When this was broken down by procedure type, open AAA had the highest rates of postoperative myocardial ischemia (9%), troponin elevation (3.9%), and myocardial infarction (5.1%), compared with carotid revascularization, endovascular aneurysm repair, and lower-extremity bypass.

The rate of 5-year survival for all procedures was 73% among those with no ischemia, 54% among those with troponin elevation, and 33% among those with myocardial infarction. This difference reached statistical significance with a P value of less than .0001. After adjusting for covariates, the researchers found a similar trend. In this analysis the rate of 5-year survival was 78% among those with no ischemia, 48% among those with troponin elevation, and 35% among those with myocardial infarction. This also reached statistical significance with a P value of less than .0001.

"We performed a subgroup analysis by procedure type, and the trend was the same across all procedure types," Dr. Simons said.

In Cox modeling the researchers found that postoperative ischemia in the form of a troponin elevation increased the hazard of death at 5 years by 45% (HR, 1.45; P =.01) while myocardial infarction nearly tripled the hazard of death (HR, 2.93; P =.0001).

"We have shown an association between postoperative myocardial ischemia and worse survival, but does postoperative myocardial ischemia worsen long-term survival, or does postoperative myocardial ischemia simply identify a high-risk subset of patients?" Dr. Simons asked. "If postoperative myocardial ischemia worsens long-term survival, then efforts should focus on better preoperative medical optimization and perioperative prevention of ischemia. If postoperative myocardial ischemia is simply identifying a high-risk subset of patients, then efforts should focus on better preoperative risk stratification and postoperative medical surveillance."

She concluded that postoperative myocardial ischemia, "whether a troponin elevation or a myocardial infarction, is associated with lower survival. This effect is seen across all procedure types and persists out to 5 years postoperatively."

Dr. Simons said she had no relevant financial disclosures.

[email protected]

SAN FRANCISCO – Postoperative troponin elevation and myocardial infarction both impact 5-year survival following vascular surgery procedures, the results of a large long-term study showed.

In fact, troponin elevation increased the hazard of death by 50% while myocardial infarction increased the hazard of death by nearly threefold, Dr. Jessica P. Simons reported at the annual meeting of the Society for Vascular Surgery. "Future studies are needed to assess the nature of this association as well as the utility of routine postoperative screening for myocardial ischemia," said Dr. Simons of the division of vascular and endovascular surgery at the University of Massachusetts, Worcester.

In a study that she presented on behalf of the Vascular Study Group of New England (VSGNE), Dr. Simons and her associates set out to determine the association of postoperative troponin elevation with long-term survival in patients undergoing vascular surgical procedures. "Postoperative myocardial infarction has been shown to impact short- and long-term mortality," she said. "In addition, troponin elevations have also been shown to negatively impact survival for a wide range of diagnoses. This has been seen in critical care medical literature and also in the general surgical population."

The researchers identified 16,363 VSGNE patients who underwent carotid revascularization, open AAA repair, endovascular AAA repair, or lower-extremity bypass between 2003 and 2011. The exposure variable of interest was postoperative myocardial ischemia, which was categorized as either no ischemia, troponin elevation, or myocardial infarction. The primary end point was survival during the first 5 years postoperatively. They used Kaplan-Meier analyses and Cox proportional hazards models to evaluate the effect of postoperative troponin elevation and myocardial infarction.

Of the 16,363 patients, 15,888 (97.1%) had no ischemia, 211 (1.3%) had troponin elevation, and 264 (1.6%) had myocardial infarction. When this was broken down by procedure type, open AAA had the highest rates of postoperative myocardial ischemia (9%), troponin elevation (3.9%), and myocardial infarction (5.1%), compared with carotid revascularization, endovascular aneurysm repair, and lower-extremity bypass.

The rate of 5-year survival for all procedures was 73% among those with no ischemia, 54% among those with troponin elevation, and 33% among those with myocardial infarction. This difference reached statistical significance with a P value of less than .0001. After adjusting for covariates, the researchers found a similar trend. In this analysis the rate of 5-year survival was 78% among those with no ischemia, 48% among those with troponin elevation, and 35% among those with myocardial infarction. This also reached statistical significance with a P value of less than .0001.

"We performed a subgroup analysis by procedure type, and the trend was the same across all procedure types," Dr. Simons said.

In Cox modeling the researchers found that postoperative ischemia in the form of a troponin elevation increased the hazard of death at 5 years by 45% (HR, 1.45; P =.01) while myocardial infarction nearly tripled the hazard of death (HR, 2.93; P =.0001).

"We have shown an association between postoperative myocardial ischemia and worse survival, but does postoperative myocardial ischemia worsen long-term survival, or does postoperative myocardial ischemia simply identify a high-risk subset of patients?" Dr. Simons asked. "If postoperative myocardial ischemia worsens long-term survival, then efforts should focus on better preoperative medical optimization and perioperative prevention of ischemia. If postoperative myocardial ischemia is simply identifying a high-risk subset of patients, then efforts should focus on better preoperative risk stratification and postoperative medical surveillance."

She concluded that postoperative myocardial ischemia, "whether a troponin elevation or a myocardial infarction, is associated with lower survival. This effect is seen across all procedure types and persists out to 5 years postoperatively."

Dr. Simons said she had no relevant financial disclosures.

[email protected]

SAN FRANCISCO – Postoperative troponin elevation and myocardial infarction both impact 5-year survival following vascular surgery procedures, the results of a large long-term study showed.

In fact, troponin elevation increased the hazard of death by 50% while myocardial infarction increased the hazard of death by nearly threefold, Dr. Jessica P. Simons reported at the annual meeting of the Society for Vascular Surgery. "Future studies are needed to assess the nature of this association as well as the utility of routine postoperative screening for myocardial ischemia," said Dr. Simons of the division of vascular and endovascular surgery at the University of Massachusetts, Worcester.

In a study that she presented on behalf of the Vascular Study Group of New England (VSGNE), Dr. Simons and her associates set out to determine the association of postoperative troponin elevation with long-term survival in patients undergoing vascular surgical procedures. "Postoperative myocardial infarction has been shown to impact short- and long-term mortality," she said. "In addition, troponin elevations have also been shown to negatively impact survival for a wide range of diagnoses. This has been seen in critical care medical literature and also in the general surgical population."

The researchers identified 16,363 VSGNE patients who underwent carotid revascularization, open AAA repair, endovascular AAA repair, or lower-extremity bypass between 2003 and 2011. The exposure variable of interest was postoperative myocardial ischemia, which was categorized as either no ischemia, troponin elevation, or myocardial infarction. The primary end point was survival during the first 5 years postoperatively. They used Kaplan-Meier analyses and Cox proportional hazards models to evaluate the effect of postoperative troponin elevation and myocardial infarction.

Of the 16,363 patients, 15,888 (97.1%) had no ischemia, 211 (1.3%) had troponin elevation, and 264 (1.6%) had myocardial infarction. When this was broken down by procedure type, open AAA had the highest rates of postoperative myocardial ischemia (9%), troponin elevation (3.9%), and myocardial infarction (5.1%), compared with carotid revascularization, endovascular aneurysm repair, and lower-extremity bypass.

The rate of 5-year survival for all procedures was 73% among those with no ischemia, 54% among those with troponin elevation, and 33% among those with myocardial infarction. This difference reached statistical significance with a P value of less than .0001. After adjusting for covariates, the researchers found a similar trend. In this analysis the rate of 5-year survival was 78% among those with no ischemia, 48% among those with troponin elevation, and 35% among those with myocardial infarction. This also reached statistical significance with a P value of less than .0001.

"We performed a subgroup analysis by procedure type, and the trend was the same across all procedure types," Dr. Simons said.

In Cox modeling the researchers found that postoperative ischemia in the form of a troponin elevation increased the hazard of death at 5 years by 45% (HR, 1.45; P =.01) while myocardial infarction nearly tripled the hazard of death (HR, 2.93; P =.0001).

"We have shown an association between postoperative myocardial ischemia and worse survival, but does postoperative myocardial ischemia worsen long-term survival, or does postoperative myocardial ischemia simply identify a high-risk subset of patients?" Dr. Simons asked. "If postoperative myocardial ischemia worsens long-term survival, then efforts should focus on better preoperative medical optimization and perioperative prevention of ischemia. If postoperative myocardial ischemia is simply identifying a high-risk subset of patients, then efforts should focus on better preoperative risk stratification and postoperative medical surveillance."

She concluded that postoperative myocardial ischemia, "whether a troponin elevation or a myocardial infarction, is associated with lower survival. This effect is seen across all procedure types and persists out to 5 years postoperatively."

Dr. Simons said she had no relevant financial disclosures.

[email protected]