Faculty Bibliography

This case report describes the occurrence of multiple coronary artery fistulae emptying into the left ventricle and includes a small communication into the left atrium. The initial diagnosis of a coronary artery fistula was made by standard and nonstandard transthoracic two-dimensional echocardiogram and Doppler interrogation. Later, multiple coronary fistulae communicating through a sinusoid and draining into the left-sided chambers were confirmed by angiography.

The clinical applicability of a method for quantifying pericardial effusion (PE) was studied. The pericardial and cardiac volumes were determined from border tracings of 2-dimensional echocardiograms fitted with 3-dimensional disk models. The PE volume was the difference between pericardial and cardiac volumes. A phantom study included 54 cases with different volumes and viewing geometry showed a correlation coefficient r = 0.98 and an accuracy of +/- 6%. A clinical study included 20 cases showing that the estimated PE volume correlated well with that drained surgically (between 100 mL and 1200 mL): y = 0.81 x + 120 mL; r = 0.91, P <.0001. The percent error, determined by the standard error of the estimate (114 mL) over mean (548 mL), was 20%. Intraobserver variability was 4% and interobserver variability 6%. The 3-dimensional disk method provides a quick and convenient way to quantify PE from 2-dimensional echocardiograms with acceptable accuracy and reproducibility.

To evaluate the sensitivity of the serum cardiac troponin I level in detecting stress test-induced myocardial ischemia, the authors conducted a prospective study including patients admitted for chest pain to the telemetry floor of Our Lady of Mercy Medical Center at Bronx, NY. Consecutive 134 telemetry patients that agreed to participate in this study were included. All of these patients had a nuclear stress test and were divided into various groups based on the prestress test probability of having coronary artery disease. To assess serum cardiac troponin I levels, blood samples were drawn before and after stress testing and compared with the stress test results. Overall, 30 patients (22%) had reversible perfusion defects on stress images, and none (0%) had increased serum cardiac troponin I levels. One patient of 18 patients (6%) in group C with negative stress test results had an elevated serum cardiac troponin I level after the stress test, but none of group A or group B patients had elevated troponin I levels. These data show that serum cardiac troponin I levels do not increase with stress test-induced myocardial ischemia.

Left ventricular ejection fractions (LVEF) are routinely measured and result in critical decision-making algorithms in cardiology. This study was conducted to compare the accepted standard two-dimensional (2-D) echocardiogram ejection fraction (EF(ECHO)) with single photon emission computed tomography rest ejection fraction (EF(SPECT)). Data were acquired and analyzed from 51 inpatients. EF(ECHO) was obtained using modified Simpson's rule in the four-chamber apical view, and gated EF(SPECT) was computed by an automated method (Siemens ICON software). Comparison between EF(ECHO) and EF(SPECT) was done by linear regression, Bland-Altman, and receiver operator characteristic (ROC) analyses. Linear regression analysis revealed EF(SPECT) = 1.12 x EF(ECHO) - 3.6%, r = 0.93, n = 51, P < 0.0001. Bland-Altman analysis showed that the limits of 95% confidence for the difference between EF(SPECT) and EF(ECHO) were - 12% to 18%. Ninety-eight percent of the datapoints were within the limits of confidence. The ROC analysis showed that the sensitivity and specificity for detecting abnormal EF (< or = 50%) were 85% and 86% with EF(SPECT), and 91% and 90% with EF(ECHO). This study showed good correlation as well as agreement between SPECT and two-dimensional echocardiograms in measuring EF.