Effects of intracoronary injection of acetylcholine on coronary collateral circulation

To clarify the effect of intracoronary injection of acetylcholine on coronary collateral circulation, acetylcholine (20 and 50 μg) was injected directly into the donor artery of 5 patients with rest angina who had angiographically demonstrable collateral channels. Coronary spasm was defined as severe vasoconstriction (≥ 90% of luminal diameter) with chest pain and/or ischemic ST-segment changes. The intracoronary injection of acetylcholine induced spasm in all the 5 patients. The site of spasm was collateral vessels in 3, and the recipient coronary artery in 2 of the 5 patients. The spasm resolved spontaneously without administration of nitroglycerin. The contralateral intracoronary injection of acetylcholine also induced diffuse coronary spasm in 4 patients. These findings indicate that collateral vessels and recipient coronary arteries of the collateral circulation are susceptible to acetylcholine. Impaired relaxation and vasospastic responses to acetylcholine presumably due to endothelial dysfunction in the collateral and recipient coronary vessels may explain, at least in part, myocardial ischemia in patients with a well-developed collateral circulation. © 1993 Wiley-Liss, Inc.     

Induction of coronary artery spasm by intracoronary acetylcholine: comparison with intracoronary ergonovine.

To investigate the mechanism of coronary spasm, we compared the action of acetylcholine with that of ergonovine in 11 patients with vasospastic angina (group 1) and in 15 patients with chest pain (group 2). Coronary arteriography was performed immediately after the patients received intracoronary injections of titrated increments of each agent. In the patients in group 1 occlusive or near-occlusive (99% luminal narrowing) coronary spasm associated with angina and ischemic electrocardiographic ST changes was noted in nine of 11 patients receiving acetylcholine and in all 11 patients receiving ergonovine. The region and the degree of the most severe coronary spasm on coronary arteriograms evoked by the two agents were the same in nine of the 11 patients in group 1. In the other two patients in group 1, spontaneous focal coronary spastic stenosis in the baseline coronary arteriogram was relieved by the intracoronary injection of acetylcholine, and a focal coronary occlusive spasm in the same region was induced repeatedly by the subsequent intracoronary injection of ergonovine (paradoxic phenomenon). In contrast, occlusive or near-occlusive coronary spasm was not induced by either agent in any patient in group 2. These results suggest that the two provocative tests for coronary spasm that involve acetylcholine and ergonovine are clinically useful in the diagnosis of vasospastic angina, but testing with intracoronary ergonovine is needed when a spontaneous focal coronary spasm is relieved by the intracoronary injection of acetylcholine. The results also indicate that in many patients with vasospastic angina, nonspecific hypersensitivity to acetylcholine or ergonovine in a definite region of the coronary arteries generally plays an important role in the induction of coronary spasm.(ABSTRACT TRUNCATED AT 250 WORDS)     

Induction of coronary arterial spasm by intracoronary administration of acetylcholine in patients with vasospastic angina

To examine whether intracoronary injections of acetylcholine induce coronary artery spasm in patients with vasospastic angina, incremental doses (20, 30 and 50 micrograms) were injected directly into the coronary arteries in 12 patients with variant angina (Group A: rest angina with electrocardiographic ST-segment elevation during attacks), 19 with vasospastic angina (Group B: rest angina and/or effort angina with variable threshold in the treadmill exercise stress test), 11 with organic coronary artery stenosis but without angina (Group C), and 14 without coronary artery disease (Group D). A temporary cardiac pacemaker was positioned in the right ventricle. Coronary artery spasm was defined as severe vasoconstriction (greater than or equal to 90% of reduction in the luminal diameter) with chest pain and/or ischemic changes in the electrocardiogram. Intracoronary injection of acetylcholine induced spasm of at least one coronary artery in all 12 patients (100%) of Group A, in 18 (95%) of Group B, in two (18%) of Group C, and in two (14%) of Group D. Thus, the sensitivity of this method for inducing coronary spasm was 100% in group A, 95% in Group B, and 97% in Group A plus Group B. The specificity for inducing spasm was 86% in Group D, and 84% in Group C and Group D. When acetylcholine was injected separately into the left and right coronary arteries, spasm of both the coronary arteries was observed in two (40%) of Group A, in five (33%) of Group B, and none (0%) of Group C and Group D. Acetylcholine (20 micrograms) induced coronary spasm in 10 (83%) of Group A and only in nine (47%) of Group B.(ABSTRACT TRUNCATED AT 250 WORDS)     

The sensitivity of intracoronary injection of acetylcholine in inducing coronary spasm differs in patients with stable and unstable angina.

In an attempt to clarify the role of coronary artery spasm in the pathogenesis of unstable angina, acetylcholine (20 and 50 micrograms) was injected directly into the coronary arteries of 19 patients with unstable effort angina (group 1), 30 patients with unstable spontaneous angina (group 2), and 15 patients with stable effort angina due to coronary artery organic stenosis (greater than or equal to 75%) (group 3). Coronary spasm was defined as severe vasoconstriction (greater than or equal to 90% of luminal diameter) with chest pain and/or ischemic ST-segment changes. Intracoronary injection of acetylcholine induced spasm of at least one coronary artery in 19 patients (100%) of group 1 and 28 (93%) of group 2 but only 3 (20%) of group 3 (p less than 0.01). When acetylcholine was injected into the left and right coronary arteries separately, multivessel spasm (spasm of both coronary arteries) was induced in 5 of 12 (42%) patients of group 1 and in 9 of 23 (39%) patients of group 2. In contrast, intracoronary acetylcholine did not cause multivessel coronary spasm in any of 15 patients of group 3 (0%). These results suggest that coronary arteries in patients with unstable effort angina as well as spontaneous angina are susceptible to spasm and that coronary artery spasm may be responsible at least in part for the genesis of attacks in these patients.     

Usefulness of intracoronary injection of acetylcholine as a provocative test for coronary artery spasm in patients with vasospastic angina

Summary In order to examine both the sensitivity and specificity of coronary artery spasm induced by intracoronary injection of acetylcholine in patients with vasospastic angina, incremental doses of acetylcholine (20, 30, and 50 µg) were injected directly into each coronary artery in 21 patients with variant angina (group A), in 28 patients with other types of vasospastic angina (group B), and in 20 patients without any significant coronary artery disease (group C). Coronary artery spasm was defined as severe vasoconstriction (90% of reduction in luminal diameter) with chest pain and/or ischemic changes in the electrocardiogram. Intracoronary injection of acetylcholine induced spasm of at least one coronary artery in 20 patients (95%) of group A, in 27 patients (96%) of group B, and in only 2 patients (10%) of group C. The low dose of acetylcholine (20 µg) induced coronary spasm more frequently in group A patients (81%) than in group B patients (43%) (P<0.05). ST-segment elevation associated with anginal attacks was significantly (P<0.05) more frequent in group A (71%) than in group B (39%). When acetylcholine was injected separately into the left and right coronary arteries, spasm of both coronary arteries was observed in 7 out of 14 of group A (50%), in 8 out of 22 of group B (36%), and in none of the 20 of group C. We concluded that intracoronary injection of acetylcholine is a sensitive and reliable method for the induction of coronary spasm in patients with vasospastic angina as well as in those with variant angina.     

Pathogenesis of unstable angina with 0- or 1-vessel disease. Important role of coronary artery spasm.

In order to examine the possible role of coronary artery spasm in the pathogenesis of unstable angina, provocative testing for coronary spasm was performed in 43 patients with unstable angina who had 0- or 1-vessel disease. Coronary spasm was induced in 20 (65%) of 31 patients by hyperventilation testing (ST increases in 18, ST decreases in 2). Anginal attacks with either ST-segment elevation or ST-segment depression in patients without a significant organic stenosis were induced in 23 (55%) of 42 patients during treadmill exercise testing. Coronary artery spasm, showing severe (> or = 90%) vasoconstriction with angina and/or ischemic electrocardiographic ST-segment deviation, was also documented angiographically in 42 (98%) of 43 patients following intracoronary injection of acetylcholine. We conclude that dynamic coronary obstruction plays an important role in the genesis of attacks in patients with unstable angina who had 0- or 1-vessel organic coronary artery disease.     

Coronary spasm-induced acute myocardial infarction associated with intracoronary thrombosis]

A 63-year-old man was admitted with an acute anteroseptal myocardial infarction. Coronary angiography performed 3 hours after the onset of chest pain revealed 99% stenosis of the proximal left anterior descending coronary artery (LAD) with delayed filling and intraluminal thrombus distal to the stenosis. After the intracoronary injection of isosorbide dinitrate, the delayed filling disappeared and a subsequent intracoronary urokinase partially dissolved the thrombus. Repeat coronary angiography in the chronic phase disclosed 75% stenosis of the LAD and disappearance of the thrombus. Intracoronary acetylcholine provoked a coronary spasm at the stenotic site of the LAD, concomitantly with chest pain and ST-segment elevation in the anterior leads. The present case demonstrated that coronary spasm plays an important role in thrombus formation and acute myocardial infarction. To date, the concept has been postulated that a dynamic interaction between atherosclerosis, platelet aggregation and spasm may work to cause coronary thrombosis and subsequently lead to acute myocardial infarction. Our report shed light on the importance of coronary spasm in the pathogenesis of myocardial infarction.     

Sensitivity and specificity of intracoronary injection of acetylcholine for the induction of coronary artery spasm

Intracoronary injection of acetylcholine has been shown to induce coronary spasm in patients with variant angina. To examine its sensitivity and specificity, incremental doses of acetylcholine (20, 50 and 100 micrograms into the left coronary artery and 20 and 50 micrograms into the right coronary artery) were injected into the coronary artery or arteries in 70 patients with variant angina (Group 1) (mean age 57 years) and 93 patients without variant angina or angina at rest (Group 2) (mean age 54 years). Forty patients of the latter group had atypical chest pain, 16 cardiomyopathy, 14 arrhythmia, 11 valvular disease, 7 stable effort angina due to advanced coronary artery disease, 3 congenital heart disease and 2 hypertension. A temporary cardiac pacemaker set at 40 to 50 beats/min was positioned in the right ventricle. Coronary spasm was defined as total occlusion or severe vasoconstriction associated with chest pain or ischemic ST changes on the electrocardiogram or both. In Group 1, acetylcholine induced spasm in 63 (90%) of the 70 patients in the artery or arteries predicted to be responsible for spontaneous attacks. In Group 2, acetylcholine induced coronary spasm only in one patient with effort angina and advanced coronary artery disease although lesser degrees of vasoconstriction (less than or equal to 75% of the luminal diameter) occurred in most patients after acetylcholine (specificity of acetylcholine thus was 99%). In conclusion, intracoronary injection of acetylcholine is sensitive and reliable for the induction of coronary spasm.     

Biphasic changes (initial increase and late decrease) in coronary sinus venous oxygen saturation during anginal attacks induced by intracoronary acetylcholine in patients with variant angina.

In order to evaluate the effects of intracoronary acetylcholine on coronary resistance vessels, oxygen saturation in coronary sinus blood was continuously measured to compare its dynamic changes during intracoronary injection of acetylcholine in both patients with variant angina and control subjects. Group 1 consisted of 6 patients without coronary artery disease. Group 2 consisted of 10 patients with variant angina and spasm in the left anterior descending coronary artery. A fiberoptic reflection oximetry system was used for the continuous measurement of coronary sinus venous oxygen saturation. Acetylcholine (20 micrograms) was injected directly into the left coronary artery over 30 s. In the group 1 patients, coronary sinus venous oxygen saturation was increased from 39 +/- 2% (mean +/- SEM) to 54 +/- 3% at 30 s, continuously climbed to 70 +/- 3% at 60 s and then gradually decreased to 53 +/- 5% at 120 s after the initiation of intracoronary injection of acetylcholine. In contrast, in the group 2 patients, coronary sinus venous oxygen saturation was transiently increased from 39 +/- 2% to 56 +/- 4% at 30 s, reversed, decreased to 52 +/- 4% at 60 s and then rapidly decreased to 36 +/- 3% at 120 s with the onset of chest pain associated with electrocardiographic ischemic changes. Coronary arteriography during attacks demonstrated a total or subtotal occlusion of the left anterior descending coronary artery due to severe spasm in all of the 10 patients. The extent of increases in coronary sinus venous oxygen saturation at 30 s after acetylcholine injection was not significantly different between the two groups (group 1: 15 +/- 4%, group 2: 17 +/- 3%). Heart rate, blood pressure and rate-pressure product were essentially unchanged at 30 s after intracoronary injection of acetylcholine in both groups. These data suggest that in control adult humans, coronary blood flow was increased through dilatation of resistance vessels by acetylcholine, while in patients with variant angina, coronary blood flow was transiently increased by dilatation of resistance vessels, after which it was suddenly decreased by spasm of an epicardial artery induced by this agent. Relaxant responses to acetylcholine of coronary resistance vessels appear to be preserved well in patients with variant angina.     

Supersensitivity of coronary arteries in variant angina to spasm induced by intracoronary acetylcholine

Acetylcholine (20 to 100 micrograms) was infused directly into coronary arteries in 10 patients with variant angina (group A), 13 subjects without coronary artery disease (group B) and 8 patients with significant organic coronary artery stenosis (greater than or equal to 50%) but without variant angina (group C) during coronary arteriography, to clarify the action of this agent on coronary arteries. Temporary pacing was performed at a demand heart rate of 40 beats/min while bradyarrhythmia developed. Coronary arteriography after administration of acetylcholine showed coronary vasoconstriction in all 10 patients (100%) of group A. Angina accompanied by electrocardiographic ischemic changes in 9 of 10 (90%, 7 ST-segment elevation and 2 depression) was provoked during this test. In the patients of group B, acetylcholine also induced vasoconstriction in 8 of 22 (36%) coronary arterial systems examined, chest pain in 3 (14%) and ST-segment deviation in none (0%). In the patients of group C, acetylcholine induced vasoconstriction in 3 of 9 (33%), chest pain in 2 (22%) and ST-segment depression in 1 (11%). No definite coronary artery dilation induced by acetylcholine was noted. Coronary vasoconstriction (p less than 0.05), electrocardiographic ischemic findings (p less than 0.01) and chest pain (p less than 0.01) were induced significantly more frequently in group A than in both groups B and group C. No significant difference was found between group B and group C. The coronary arteries in the patients with variant angina seem to be more susceptible to acetylcholine than those of patients without variant angina irrespective of the presence of significant atherosclerosis.     

乙酰胆碱诱发冠状动脉痉挛试验中缓慢型心律失常的原因探讨

目的探讨乙酰胆碱诱发冠状动脉痉挛试验中缓慢型心律失常的发生原因。方法64例因静息性胸痛而接受冠状动脉造影的患者,排除具有缺血意义的病变后进行乙酰胆碱试验,术中连续记录心电图变化,比较痉挛组和非痉挛组缓慢型心律失常情况,并选择冠状动脉痉挛合并缓慢型心律失常的25例患者分别在冠状动脉内注射硝酸甘油及静脉注射阿托品后重复乙酰胆碱试验,观察冠状动脉痉挛和心律失常的变化情况。结果乙酰胆碱试验痉挛组(46例)和非痉挛组(18例)缓慢型心律失常的发生率无差异(P>0.05),痉挛组中14例经过冠状动脉内注射硝酸甘油后重复乙酰胆碱试验均未能诱发痉挛,但12例仍出现缓慢型心律失常,另11例静脉注射阿托品后重复乙酰胆碱试验均未诱发冠状动脉痉挛,仅1例出现缓慢型心律失常。结论乙酰胆碱试验中的缓慢型心律失常可能与乙酰胆碱的药理作用有关而与冠状动脉痉挛无关。     

Continuous intracoronary nitroglycerin infusion for spasm after angioplasty

A patient with reversible coronary artery spasm superimposed on fixed atherosclerotic coronary disease was treated with percutaneous transluminal angioplasty. The procedure successfully dilated the atherosclerotic lesion. However, 20 minutes later, the patient developed coronary artery spasm at the angioplasty site. Sublingual nitroglycerin, sublingual nifedipine, intravenous nitroglycerin, and repeated boluses of intracoronary nitroglycerin alleviated episodes of spasm, but failed to prevent recurrence. The patient was successfully treated with a continuous intracoronary infusion of nitroglycerin. Patients with coronary artery spasm in addition to fixed obstructive coronary disease may be at higher risk for spasm after percutaneous transluminal angioplasty. Continuous intracoronary infusion of nitroglycerin may be an effective therapy for recurrent coronary artery spasm occurring in the catheterization laboratory.     

A case of vasospastic angina presenting Brugada-type ECG abnormalities.

An electrophysiological study and a provocative test of coronary artery spasm was attempted in a 68-year-old man who was having syncopal attacks and chest pain. His electrocardiogram had the characteristics of Brugada syndrome and ventricular fibrillation (VF) was induced by programmed electrical stimulation. ST-segment elevation became exaggerated by procainamide, which could not prevent the induction of VF. Coronary angiography revealed no stenotic lesions, and spasm in the left coronary artery was induced by intracoronary administration of acetylcholine with similar chest pain to that experienced before. Under treatment with diltiazem and flecainide, which suppressed the induction of VF, the patient experienced no recurrence of symptoms despite persistent ST-segment elevation. No previous reports have described coronary spasm associated with Brugada-type ECG abnormalities, and patients with syncope should be evaluated carefully.     

Coronary arteriographic findings during early hours of acute myocardial infarction: response to intracoronary injection of nitrates

We performed coronary arteriography and gave intracoronary injection of nitrates within 8 hours after the onset of symptoms of acute myocardial infarction in eighteen patients. Improved distal filling or patency of the total occluded coronary artery after intracoronary injection of nitrates occurred in 4 of 18 patients. In one of four patients the first intracoronary nitrates injection failed to release the initial total occlusion, but after intracoronary Urokinase administration, the second nitrates injection succeeded to dilate the completely occluded coronary artery. Coronary arteriography was again performed in sixteen patients in the chronic stage (4-15 weeks after the onset of acute myocardial infarction) and ergonovine maleate was injected intravenously in seven patients. Focal spasm was induced by ergonovine injection in three patients in one of whom intracoronary nitrates failed to release the complete obstruction in the acute stage. We conclude that coronary spasm as well as intracoronary thrombosis plays an important role in the production of acute myocardial infarction.     

Intracoronary verapamil for reversal of refractory coronary vasospasm during percutaneous transluminal coronary angioplasty

Coronary artery spasm unresponsive to intracoronary nitroglycerin was observed in eight patients undergoing percutaneous transluminal coronary angioplasty for unstable ischemic symptoms (unstable angina or recent nontransmural infarction, or both). All patients manifested eccentric lesions angiographically with the right coronary artery involved in four, circumflex artery in two and left anterior descending in two. Severe coronary spasm was documented angiographically in all patients after angioplasty and resulted in symptomatic and electrocardiographic evidence of ischemia. Multiple sites of spasm were present in the dilated vessel in three patients. Coronary artery spasm persisted despite the infusion of large doses of intracoronary nitroglycerin (200 to 2,000 micrograms, mean 850 micrograms) over 10 min. Administration of intracoronary verapamil (1 to 1.5 mg over 10 min) resulted in complete relief of spasm with restoration of brisk anterograde flow in all patients. These findings suggest that intracoronary verapamil may be a useful agent for the relief of coronary spasm occurring in the setting of coronary angioplasty.     

Comparative sensitivity of intracoronary injection of acetylcholine for the induction of coronary spasm in patients with various types of angina pectoris

To elucidate the possible contribution of coronary artery spasm to the pathogenesis of angina pectoris, coronary arterial responses to intracoronary injection of acetylcholine were examined in patients with various types of angina pectoris. Coronary artery spasm with chest pain and/or electrocardiographic ischemic changes was angiographically demonstrated in 50 (85%) of 59 patients with angina pectoris. The sensitivity for coronary spasm was 92% (24 of 26) in patients with rest angina, 100% (16 of 16) in patients with both rest and effort angina, and 59% (10 of 17) in patients with effort angina, while it was only 6% (1 of 16) in patients without coronary artery disease. When patients with effort angina were subdivided according to the variability of anginal threshold for exertional angina, the sensitivity for coronary spasm was as high as 90% (9 out of 10) in patients with variable-threshold angina. In contrast, coronary spasm was less frequently (p less than 0.05) induced in patients with fixed-threshold angina (1 of 7, 14%). These results suggest that coronary arteries in patients with angina pectoris are quite susceptible to acetylcholine except in those patients with stable exercise tolerance or anginal threshold. Thus coronary artery spasm appears to play a significant role for the pathogenesis of angina pectoris in a large proportion of patients with effort angina as well as in patients with rest angina.     

Acute myocardial infarction showing total occlusion of right coronary artery and thrombus formation of left anterior descending artery

A 33-year-old Japanese man had an attack of chest pain associated with ST-segment elevation in the inferolateral leads on his electrocardiogram. Emergency coronary angiography showed total obstruction in the mid right coronary artery (RCA) and a movable thrombus in the proximal left anterior descending artery (LAD). We performed emergency percutaneous transluminal coronary angioplasty (PTCA) for the RCA lesion. The operation was successful and we then conducted intracoronary thrombolysis (ICT) with tisokinase 6,400,000 IU for the LAD thrombus. Its size was reduced by ICT. He had an uneventful hospital course. After 1 month, repeat coronary angiography showed no significant stenosis in the RCA nor thrombus in the LAD. A coronary spasm provocation test was performed using acetylcholine. Coronary spasm in the LAD was induced by an intracoronary injection of 100 microg acetylcholine. In this case, we observed a unique condition suggesting simultaneous double coronary artery occlusion.     

New combined spasm provocation test in patients with rest angina: intracoronary injection of acetylcholine after intracoronary administration of ergonovine

The incidence of provoked coronary spasm with the standard single spasm provocation test has been relatively low in patients with rest angina. The present study examined the clinical usefulness of a newly designed spasm provocation test, an intracoronary injection of acetylcholine (ACh) following an ergonovine (ER) test, in patients with rest angina who demonstrated low disease activity and atypical chest pain. Triple sequential spasm provocation tests were performed in 24 patients with atypical chest pain who had no ischemia and in 40 patients with rest angina who had distinct ischemia. Initially, an ACh test (20-100 microg) and then an ER test (40-64 microg) were performed and then, if no spasm was provoked, an intracoronary injection of ACh was given after the ER test to evaluate coronary spasm. Coronary spasm was defined as total or subtotal occlusion. In the 24 patients with atypical chest pain, no spasm was provoked by intracoronary injection of either ACh or ER, but coronary spasms were induced in 2 patients using the new method, with the remaining 22 not experiencing spasm (specificity of new method, 92%). In the 40 patients with rest angina, intracoronary injection of ACh induced coronary spasm in 22 patients (group I) and 6 (group II) demonstrated spasm with intracoronary injection of ER. Coronary spasm was not induced by either the ACh test or the ER test in 12 patients (group III). The intracoronary administration of ACh after the ER test provoked spasm in 11 of 12 patients. Diffuse spasms were provoked in 10 of 11 patients. In patients with rest angina, the frequency of chest pain attacks in 1 month experienced by patients in group III (0.8+/-0.8) was significantly lower than that of patients in group I (7.0+/-5.3, p<0.01) or II (3.5+/-2.3, p<0.05). No serious or irreversible complications related to this new combined method were observed. In conclusion, this method was safe and reliable for the induction of coronary spasm in patients with rest angina who may have low disease activity.     

Coronary vasospastic activity at sites of percutaneous transluminal coronary angioplasty: evaluation using intracoronary acetylcholine administration]

To investigate coronary vasospastic activity after percutaneous transluminal coronary angioplasty (PTCA), we performed intracoronary injection of acetylcholine in 55 patients, mean 3.3 months after successful PTCA. Coronary spasm was defined as transient total or subtotal occlusion of the PTCA sites. Sixty-nine lesions of the 55 patients were examined to determine whether spasm was provoked by incremental doses of acetylcholine. Restenosis was defined as coronary luminal narrowing of > or = 50% after nitroglycerin or isosorbide dinitrate. Twenty of the 55 patients (36%) and 23 of the 69 lesions (33%) had coronary spasm. There was no correlation between the incidence of coronary spasm and the interval from PTCA to the acetylcholine test. The spasm was provoked in 17 lesions of the 50 non-restenotic lesions (34%) and was also provoked in 6 of the 19 restenotic lesions (32%). On the other hand, restenoses occurred in 6 of the 23 spastic lesions (26%) and in 13 of the 43 non-spastic lesions (28%). There was no correlation between the incidence of coronary spasm and the occurrence of restenoses. Twenty-four patients had undergone acetylcholine provocative test before PTCA. Among these 24 patients, 11 had coronary spasm before PTCA, and 7 had coronary spasticity after PTCA. Four patients who had positive evidence of coronary spasm before PTCA did not show negative spasm after PTCA. On the other hand, 3 patients who did not show evidence of coronary spasm showed positive evidence of coronary spasm after PTCA.(ABSTRACT TRUNCATED AT 250 WORDS)     

Multivessel coronary spasm in patients with variant angina: a study with intracoronary injection of acetylcholine

Multivessel coronary spasm has been described but its incidence in patients with variant angina still remains unclear. Thirty-three patients with variant angina were studied during coronary angiographic examination with selective intracoronary injection of acetylcholine (ACh). In all but three patients, the location of ischemia during attack was determined by the electrocardiographic findings, by exercise 201Tl myocardial scintigraphy, and by two-dimensional echocardiography during a hyperventilation test, and the coronary artery (or arteries) responsible for the attack was predicted before the study. ACh induced spasm of at least one coronary artery in all but one patient. ACh induced spasm of both the left and right coronary arteries (i.e., multivessel coronary spasm) in 24 patients: in two of the four patients who were predicted to have spasm of the left coronary artery, in six of the 11 predicted to have spasm of the right coronary artery, in 13 of the 15 predicted to have spasm of both the left and right coronary arteries, and in three of the three in whom coronary artery responsible for attack had not been predicted. This ACh-induced spasm of the left and right coronary arteries occurred separately and no patients showed hemodynamic instability during attack. In one patient in whom multivessel coronary spasm had been predicted and ACh failed to induice coronary spasm, ergonovine maleate (0.2 mg) induced spasm of both the left and right coronary arteries simultaneously, resulting in severe prolonged hypotension. Nineteen of the 25 patients in whom multivessel coronary spasm was documented showed angiographically normal or nearly normal coronary arteries after administration of nitroglycerin.(ABSTRACT TRUNCATED AT 250 WORDS)