Clinical Observational Study Investigating the Role of Diastolic Dysfunction in Determining Abnormal Cardiorespiratory Exercise Testing Parameters in Patients Undergoing Major Surgery

REASON FOR STUDY

Major non-cardiac surgery has a high degree of morbidity and mortality. Recently, suitable measurements of a patient's preoperative cardiorespiratory reserve, performed non-invasively by cardiopulmonary exercise testing, have been shown to be predictive of outcome following non-cardiac surgery. Although the exact mechanisms behind poor reserve in this population are unknown, poor cardiac function and particularly diastolic dysfunction are likely to be important.

AIMS

The aim of the present study is to investigate the role of diastolic dysfunction in determining poor cardiorespiratory reserve in elderly patients undergoing major non-cardiac surgery. This will provide suitable information to inform a further therapeutic preoperative interventional study.

OBJECTIVES AND METHODS

1. To determine the presence and severity of diastolic dysfunction, measured by preoperative transthoracic echocardiogram, in a series of elderly surgical patients undergoing major elective non-cardiac surgery
2. To investigate the relationship between diastolic dysfunction and poor cardiorespiratory function during and following exercise measured by non-invasive testing including cardiopulmonary exercise testing, non-invasive blood pressure measurements and biochemical analysis
3. To determine whether patients with poor diastolic dysfunction are likely to have worse outcomes following major surgery compared with those who show no evidence of diastolic dysfunction. Outcomes will be measured in terms of length of hospital stay and early postoperative morbidity (validated scoring system) and mortality.