No abstract

Transvenous stress atrial pacing (SAP) was performed in conjunction with two-dimensional echocardiography (2DE) and compared to radionuclide angiography (RNA) in 15 patients with coronary artery disease (CAD). In addition, 10 normal subjects underwent SAP-2DE only. The test was successful in 93.3 % of the CAD patients and in all normal subjects. Echocardiographie images of good quality were obtained at rest and throughout atrial pacing in all subjects. In normal subjects the ejection fraction (EF) increased from 62 ± 6.3 to 64 ± 7% during maximal SAP (p = NS). None showed wall motion abnormalities (WMA) at rest or during SAP. In the CAD group the EF decreased from 46.5 ± 11 to 30 ± 7% (p < 0.001) by SAP-2DE and from 47 ± 12 to 29 ± 10% (p < 0.001) by SAP-RNA. SAP-induced WMA or deterioration of previously diseased segments were detected in 92.8 % of the CAD patients by 2DE and in 71.4% by RNA. The overall sensitivity of the method was 87%; however, in those in whom SAP was successfuly completed, sensitivity and specificity of SAP-2DE in detecting CAD were 92.8 and 100%, respectively, by WMA criteria, while the sensitivity of RNA was 71.4%. According to EF criteria, the sensitivity of both 2DE and RNA was 92.8%. SAP-2DE was superior to SAP-RNA in localizing diseased vessels seen in coronary angiography. We conclude that SAP-2DE is a feasible and clinically applicable technique for the diagnosis of CAD and compares favorably with SAP-RNA. It is of particular value in patients who cannot perform dynamic exercise tests.