Relation between systemic hypertension and pain perception.

To test the hypothesis that hypertension diminishes pain perception, a study was made that evaluated the relation between arterial blood pressure and thermal pain perception in human subjects. The average mean arterial pressure in all 20 men studied (10 hypertensive, 10 normotensive) proved to be significantly related to both thermal pain threshold (p = 0.05) and tolerance (p = 0.003). The difference between normotensive and hypertensive groups in baseline and posttest plasma levels of beta endorphin was also significant (p = 0.02) and indicated an interaction between endogenous opioids and blood pressure. Other recent studies of hypertension in relation to hypalgesia were also reviewed. An increased pain threshold was found in hypertensive versus normotensive rats. In cats, electrical stimulation of vagal afferent nerves (cardiopulmonary baroreceptors) suppresses nociceptive responses, and both pharmacologic elevation of blood pressure and vascular volume expansion produce antinociception. Together with preliminary findings in human studies, these results indicate an interaction between pain-controlling and cardiovascular regulatory functions that is probably mediated by the baroreceptor system.

Prognostic value of exercise echocardiography in women in the community setting.

Treadmill stress echocardiography was performed in 1,136 women with known or suspected coronary artery disease whose clinical course was then evaluated a mean of 33 months later (range 12 to 60). The strongest predictor of an adverse outcome was the presence of a resting or an exercise-induced wall motion abnormality.

Prediction of cardiac mortality after myocardial infarction: the role of maximal treadmill stress echocardiography.

Patients frequently undergo low-level exercise treadmill testing after acute myocardial infarction (MI) and, in the absence of inducible ischemia, a maximal test several weeks later. This study examines 203 patients who had 2-dimensional echocardiography before and after a maximal Bruce protocol exercise treadmill test performed 4 to 6 weeks after MI. The subjects were followed for a mean of 43 months (range 1 to 77 months). Predictors of cardiac mortality by multivariate or univariate analysis included an ejection fraction < or =40%, diabetes, age > or=70 years, and ischemia by exercise echocardiography but not by electrocardiography. Therefore, standard electrocardiographic monitoring during exercise treadmill testing 6 weeks after MI fails to predict cardiac mortality. The addition of pre-exercise and post-exercise treadmill stress echocardiography to readily available clinical parameters identifies those patients at greatest risk for cardiac death (resting ejection fraction < or=40%) and detects residual exercise-induced ischemia that may be of additional prognostic value.