Troponin T Elevation in Patient Undergoing Hip Fracture Surgery

Background: Patients undergoing hip fracture surgery are elderly and usually have co-morbidities; hence they are at risk for perioperative MI. Troponin is the gold standard for diagnosis of myocardial damage and currently the cornerstone of MI diagnosis. Perioperative troponin elevation is a poor prognosis factor. The significance of minor troponin elevation, detected by highly sensitivity troponin T assay, is unknown.

Objectives: To determine the frequency of perioperative troponin T elevation using highly sensitivity troponin T assay, and to determine the clinical significance of this elevation.

Methods: Serum Troponin T levels of patients undergoing hip fracture surgery will be tested prior to surgery 48 hrs and 72 hrs after surgery, using highly sensitivity troponin T assay.

Patients will be followed for 1 year. Primary outcomes- The number of patients with elevated troponin levels perioperatively and cardiac mortality at 3 months, 6 months and 1 year.

Background and Rational

Hip fractures are an important cause of morbidity and mortality in the elderly. Surgery (i.e. total hip fracture surgery or replacement) is associated with better outcome; however these elderly patients have other comorbidities which put them at risk for non surgical perioperative complications .

Peri-operative myocardial infarction (MI) is associated with increased mortality and morbidity . Peri-operative MI currently diagnosed by presence of either symptoms or ischemic ECG changes, together with an elevated troponin level as measured by conventional assay.

The new highly sensitive troponin T (HS Tn T) assay, permitting measurement of concentrations that are lower by a factor of 10 than those measurable with conventional assays .

Research Objectives

The fundamental objective of our research is to further elucidate the magnitude and clinical relevance of minor perioperative TnT elevations.

Our specific objectives are:

A.To determine what is the frequency of HS Tn T elevation in patients undergoing hip fracture surgery.

B.To determine whether the presence of perioperative Tn T elevation using the HS assay is associated with higher mortality and morbidity.

Primary end points:

1. The number of patients with elevated HS Tn T levels postoperatively.
2. Cardiac mortality at 3 moths, 6 months and 1 year.

Secondary end points:

1. Total mortality at 3 moths, 6 months and 1 year.
2. Hospitalization for ACS and/or CHF at 3 months, 6 months and 1 year.

Methods

Patients admitted with traumatic femoral neck fracture will be recruited if surgery is planned.

Clinical evaluation for symptoms and signs of myocardial ischemia will be performed prior to surgery and 24 hrs after surgery.

Serum Tn T levels will be tested prior to surgery 48 hrs and 72 hrs after surgery, using HS Tn T assay.

ECG monitoring will be performed prior to surgery and 24 hrs after surgery. Patients will be followed for 1 year.

Eligibility Criteria:
Inclusion Criteria:

* Patients older than 65 years, admitted with traumatic femoral neck fracture undergoing surgery

Exclusion Criteria:

* Patients who will not undergo surgery
* Patients whom clinical singes and baseline troponin (prior to surgery) will suggest an acute myocardial infarction
* Patient younger than 65 years