- Low hot pain threshold predicts shorter time to exercise-induced angina: results from the psychophysiological investigations of myocardial ischemia (PIMI) study. Sheps, D.S., McMahon, R.P., Light, K.C., Maixner, W., Pepine, C.J., Cohen, J.D., Goldberg, A.D., Bonsall, R., Carney, R., Stone, P.H., Sheffield, D., Kaufmann, P.G. J. Am. Coll. Cardiol. (1999)