Carotid sinus reflex in patients undergoing coronary angiography: relationship of degree and location of coronary artery disease to response to carotid sinus massage.

Heart rate and blood pressure responses during and after carotid sinus massage were examined in 66 patients just before coronary angiography. A significant relationship was found between heart rate and blood pressure responses and (1) angina pectoris class, (2) total coronary artery disease score and (3) presence of high-grade (> 90%) stenosis of any of the three major coronary arteries. Only patients with contraction abnormalities of the anterolateral left ventricular region had greater cardionhibitory responses than patients with normal left ventricular angiograms. Among patients with normal left ventricular angiograms, those with more than 50% stenosis of one or more vessels had significantly (p < 0.01) greater responses than those with no or minimal coronary artery disease. All 21 hypersensitive (asystole longer than 3 seconds) patients had significant multivessel coronary artery stenoses or single-vessel high-grade stenosis (greater than or equal to 90%) proximal to the atrioventricular nodal artery. None of the 11 patients with normal coronary arteries had an exaggerated response to carotid sinus massage. These data support the association of an exaggerated response to carotid sinus massage in the presence of symptomatic coronary artery disease and suggest that the magnitude of response is influenced by the severity of the disease.