Can the cold pressor test predict future cardiovascular events in patients without demonstrated ischemic heart disease by SPECT?

ObjectiveTo assess whether a cold pressor test (CPT) could help identify patients at a high risk of cardiovascular events in a population without known coronary artery disease (CAD) with a normal myocardial perfusion scintigraphy (MPS).MethodsOur population consisted of 870 patients with a mean age of 59.3 years with several CAD risk factors, having been referred for an MPS. The CPT was performed between the third day and fifth day after the MPS.ResultsThe CPT was positive in 38.2% of the patients. After a mean 40-month follow-up, the patients were contacted to check for cardiac death, non-fatal myocardial infarction, and myocardial revascularization procedures. The event-free survival rates were 98.1% and 90.4% after a negative or positive CPT, respectively (p = 0.0001). The positive CPT group exhibited a fourfold increased risk of CV events. All CV events in the negative CPT group occurred after a 30-month follow-up. The risk of CV events was 4.5 times higher in diabetic patients.ConclusionA positive CPT in patients with a negative MPS could help identify a subgroup of patients at a higher risk of developing symptomatic CAD.Practice implicationsOur results suggest that after a normal post-exercise MPS, patients should undergo a CPT.