The Role of Epicardial Echocardiography in the Measurement of Transvalvular Flow Velocities During Aortic Valve Replacement

Difficult TEE Probe Placement: The Evidence, Troubleshooting Techniques, and a Guide to Alternative Monitoring Options for Intraoperative Physicians

Transesophageal echocardiography (TEE) imaging has become an essential component of many open and interventional cardiac procedures and has increasing use in monitoring for noncardiac procedures, partly because of an aging population. Whether expected or not, encountering difficulty when inserting the TEE probe presents the anesthesiologist with a conundrum. Repeated insertion attempts increase the risk of a serious complication; however, proceeding without TEE may be unacceptable to the proceduralist or surgeon. The aim of this review is to present the spectrum of complications possible with TEE, propose several evidence-based insertion tips, examine potential alternative cardiac imaging options, and finally, propose a roadmap for providers who encounter difficulty when placing a TEE probe.

Evaluation of tricuspid and pulmonary valves using epicardial and transesophageal echocardiography--a comparative study

OBJECTIVE

To compare measurements obtained by transesophageal echocardiography (TEE) and epicardial echocardiography (EE) for evaluation of the tricuspid valve (TV) and pulmonary valve (PV).

DESIGN

Prospective observational.

SETTING

University hospital.

PARTICIPANTS

Patients undergoing elective coronary artery bypass grafting with or without aortic valve replacement.

INTERVENTIONS

After routine intraoperative TEE, EE was performed to compare measurements obtained by the 2 methods.

MEASUREMENTS AND MAIN RESULTS

After institutional review board approval, 25 patients >18 years old were recruited. Biases with EE versus TEE for E and A waves were 11.9 cm/second (95% confidence interval [CI], 48.2 to -24.4) and 6.8 cm/second (95% CI, 28 to -15), respectively, and for E/A ratio was 0.08 (95% CI, 1.2 to -1). Pulmonary velocity bias was 57.94 cm/second (95% CI, 192.9 to -76.98), with higher values using EE. Bias for pulmonary trunk diameter was -0.31 cm (95% CI, 1.5 to -2.1). For quality of images, means were 2.4 (standard deviation [SD], 1.0) for EE and 2.3 (SD, 0.57) with TEE for TV and 2.4 (SD, 1.0) with EE and 2.5 (SD, 1.0) with TEE for PV. For the number of leaflets visualized, means were 2.2 (SD, 1.0) with EE and 2.5 (SD, 0.5) with TEE for TV and 2.5 (SD, 0.5) for EE and 1.3 (SD, 1.1) with TEE for PV.

CONCLUSIONS

There was good agreement for Doppler measurements across TVs; however, measurements across PVs were significantly higher with EE versus TEE. TV Doppler measurements were difficult to acquire even for surgeons experienced in epiaortic scanning.