Altered adrenergic activity in coronary arterial spasm: Insight into mechanism based on study of coronary hemodynamics and the electrocardiogram

alpha-Adrenergic receptors and coronary spasm: an elusive link.

“…In the period preceding episodes of ischemia, we could not detect signs of increased sympathetic activity to the heart such as an increase in heart rate or prolongation of the QT interval, as described by Ricci et al 4 We believe that the discrepancy between our results and those reported by these authors can be largely explained by methodologic differences. The finding of prolonged QT intervals before ischemia was probably related to the inability to accurately determine the onset of the ST segment by manual measurements.…”

“…After analog-to-digital conversion at 100 samples/sec, recordings from the lead showing the most evident changes during ischemia were processed by a computer program that we had developed and validated against standard reference techniques,69 with use of a 1OOOF Hewlett Packard computer. For the whole of each 24 hr tape the following parameters were calculated on a beat-bybeat basis: (1) heart rate, (2) ST-T positive and negative areas, (3) level of J point (J1), (4) ST segment level 80 msec after J point (J2), and (5) corrected QT interval (QT/VkR). The beatto-beat values of each derived parameter were averaged on 10 sec periods and plotted against time by a 2608A Hewlett Packard line printer.…”

Poor responsiveness of heart rate to treadmill exercise in vasospastic angina

“…In some patients with Prinzmetal's variant angina, the role of the autonomic nervous system in the pathophysiology of coronary spasm has been well established (Ricci et al, 1979;Yasue et al, 1974). Nevertheless, the predictive value of heart rate response to exercise in detecting the presence of vasospastic angina was unknown.…”

“…On the other hand, the role of the autonomic nervous system in the pathophysiology of coronary spasm has been well established in some patients with vasospastic angina (Ricci et al, 1979;Yasue et al, 1974). Autonomic nervous disturbance may contribute to a condition participating in provocation of coronary spasm.…”

Guía sobre el manejo de la angina estable. Versión resumida

“…En la mayoría de los casos es necesaria una terapia combinada con nitratos de acción prolongada y altas dosis de antagonistas del calcio para conseguir una mejoría de los síntomas. El papel de los bloqueadores beta es controvertido, aunque se ha informado de beneficios terapéuticos ocasionales 227 . El nicorandil, un activador de los canales de potasio, puede ser útil también en algunos pacientes con angina vasoespástica pertinaz 228 .…”