T. Barton

Transthoracic Echocardiography Is Still Useful in the Initial Evaluation of Patients With Suspected Infective Endocarditis: Evaluation of a Large Cohort at a Tertiary Referral Center

OBJECTIVES To examine the sensitivity of contemporary transthoracic echocardiography (TTE) for the detection of vegetation, abscess cavity, or prosthetic valve dehiscence (Vg) in patients with suspected infective endocarditis (IE) and to identify whether a relatively normal initial TTE finding can be effectively used as a rule out test, obviating the need for transesophageal echocardiography (TEE). PATIENTS AND METHODS We evaluated clinical, microbiological, and echocardiographic data for all patients with suspected IE referred for both TTE and TEE between January 1, 2005, and December 31, 2010. Patients were stratified into 3 groups by baseline TTE findings: negative TTE (native valves with less than or equal to mild regurgitation and no Vg), equivocal TTE (no Vg but prosthetic valve or greater than mild native valvular regurgitation), and positive TTE (Vg detected). RESULTS We studied 622 consecutive patients (68% male; mean ± SD age, 62 ± 17 years), including 256 with Staphylococcus aureus bacteremia (SAB). The presence of Vg was confirmed by TEE in 141 patients (23%). The TTE had low sensitivity for the detection of Vg (58%). A total of 271 patients (44%) had an initial negative TTE. Of these, TEE demonstrated Vg in only 8 patients (negative predictive value [NPV] of negative TTE, 97%). The negative TTE group included 132 patients with SAB, only 6 of whom had Vg (NPV, 95%). Of 265 patients with equivocal TTE, Vg was demonstrated in 51 (19%). CONCLUSION In a hospital population with clinically suspected IE, TTE had low sensitivity for the detection of Vg; however, a negative initial TTE was a common finding, with a high NPV, even in the setting of SAB. A TEE may be avoided in many patients with suspected IE.

Feasibility of exercise stress echocardiography for cardiac risk assessment in chronic kidney disease patients prior to renal transplantation

Pharmacologic stress testing is utilized in preference to exercise stress echocardiography (ESE) for cardiac risk evaluation in potential renal transplant recipients due to the perceived lower feasibility of ESE for achieving adequate workload and target heart rate (THR) in this population.

The Impact of Increased Pulmonary Velocity on Estimated Pulmonary Artery Pressure During Exercise Stress Echocardiography

Background: Assessing pulmonary artery pressure (PAP) during stress echocardiography (ESE) is recommended for patients with dyspnoea and valvular heart disease. Right ventricular systolic pressure (RVSP) equals PAP in the absence of significant right ventricular outflow tract gradient/obstruction. When reporting resting transthoracic echocardiograms, the antegrade pulmonary gradient is routinely subtracted from RVSP when the pulmonary velocity (PV)≥ 1.5m/s (9mmHg), however this correction has not been applied during ESE despite increased pulmonary flow associated with exercise. We evaluated the impact of increased PV with exercise on estimated PAP. Methods: We prospectively evaluated 114 consecutive patients referred for ESE (mean age 55, female 47%). Peak pulmonary and tricuspid velocities (TV) were obtained pre and post-exercise. RVSPwas calculatedwhere an adequate TR Doppler envelope was obtained. Results: PV was obtained in all patients preand post-exercise. PV increased from 1.03± 0.46m/s to 1.57± 1.0m/s post-exercise (p 1.5m/s, mean peak corrected PAP was significantly lower than if uncorrected (31.2± 9.3mmHg vs 43.6± 9.7mmHg, p 40mmHg (15% vs 60%, p= 0.003) and PAP>50mmHg (5% vs 25%, p= 0.07). Conclusions: In a cohort of patients undergoing ESE, a significant proportion of patients had a PV>1.5m/s postexercise.Correcting for PV resulted in a significantly lower calculatedPAPpost-exercise suggesting that current practise may overestimate PAP with exercise.