Quantification of Right Ventricular Function Using Simultaneous Transthoracic and Transoesophageal Echocardiography

The hypothesis of this study that perioperative TOE is useful in quantifying RV function, and that the quantification methods used will correlate well to commonly used, well-studied TTE parameters obtained simultaneously, under the same loading conditions.

Assessment of RV function is of particular importance in the perioperative period. RV dysfunction can be due to a myriad of causes - myocardial ischemia, pulmonary embolism, pulmonary hypertension, congenital heart disease, or cardiomyopathy. The presence of RV failure can lead to difficulty in separation from cardiopulmonary bypass in cardiac surgical patients, and has been shown to be an independent predictor of mortality in high-risk cardiac surgery patients. Additionally, correct identification of RV dysfunction is crucial in order for the correct treatment to be administered. RV failure can lead to underfilling of the left ventricle, and mimic hypovolaemia with hypotension and an exaggerated stroke volume variation. In such a case, failure to diagnose RV dysfunction can wrongly lead to fluid loading and further worsening of right ventricular failure.

While evaluation of right heart function is well described in TTE studies, there is insufficient data at present to recommend a reliable method to quantify RV function using TTE.

In addition to traditional measurements of RV function, we hope to study the usefulness of speckle tracking and strain imaging in assessment of RV function, modalities of echocardiographic image analysis which have garnered increasing interest in recent years.