Clinical significance of cold pressor testing in patients with ischemic heart disease

Thirty-four patients with chest pain were studied with intravenous digital subtraction angiography during cold pressure to quantitatively determine left ventricular ejection fraction (EF) and left ventricular regional wall motion (RWM). Thallium-201 exercise blood pool scanning was also undertaken in 32 patients. Coronary arteriography diagnosed 17 patients as having coronary artery disease (CAD) with significant stenosis. The remaining 17 patients were defined as normal controls (NC). Left ventricular EF was significantly lowered by cold pressure in the CAD group, but remained unchanged in the NC group. Exercise did not induce significant changes of EF in either group. Regional wall motion abnormality occurred at the time of cold pressure in 15 patients (88%) in the CAD group, and in 8 patients (47%) in the NC group. Exercise-induced RWM abnormality was seen in 14 patients (88%) in the CAD group and in only 3 patients (19%) in the NC group. Cold pressure in digital subtraction angiography had a high sensitivity in diagnosing CRD. A low specificity of cold pressure may be explained by chest pain syndrome included in this series. In patients with chest pain syndrome, the response to cold pressure may be different from that to exercise pressure. (Namekawa, K)