Prinzmetal's variant angina. Coronary arteriogram and left ventriculogram during angina attack induced by methacholine

Electrocardiographic poor R wave progression III. The normal variant

Electrocardiographic poor R wave progression (PRWR) is found in patients with anterior myocardial infarction, left ventricular hypertrophy and right ventricular hypertrophy, and is also seen in apparently normal individuals. Technical and constitutional factors that might contribute to PRWP in normal subjects were examined. Prospective analysis of the effect of precordial lead misplacement and respiratory variation on the surface ECG was performed in 68 hospitalized patients. Both false positive and false negative PRWP were created with superior and inferior lead position change respectively. The incidence and mechansim of true PRWP were analyzed by retrospective analysis of ECGs and records of 100 individuals with normal findings, and 50 additional individuals with mitral valve prolapse, at cardiac catheterization with coronary angiography. PRWP occurred in 8% (8/100) of normals and was not related to age, sex, height, weight, body surface area, ponderal index, thoracic skeletal abnormalities, ECG frontal axis, serum cholesterol, arterial blood pressure or mitral valve prolapse. In view of the voltage changes produced by alteration of lead placement, one tail of a normal distribution of null planes may account for PRWP in subjects without disease.

Syndrome of symptomatic coronary arterial spasm with nearly normal coronary arteriograms

The clinical manifestations of symptomatic coronary arterial spasm were analyzed in 30 patients whose coronary arteriograms demonstrated no fixed severe obstructions. The study group consisted of 14 men and 16 women (average age, 47 years). Angina at rest was invariable and it was usually typical in quality, location, duration and response to nitroglycerin. Exertional angina occurred in 23 percent and syncope with angina in 33 percent. Spontaneous remission of angina for at least 1 month occurred in 57 percent of patients. Prinzmetal's variant angina occurred in 77 percent of patients and only S-T segment depression or T wave changes during angina occurred in 23 percent. Major arrhythmias during ischemia developed in 47 percent. Exericse tests were positive in 24 percent. Myocardial infarction, probably due to coronary spasm, occurred in 7 percent of patients. Isosorbide dinitrate and propranolol were effective therapy in only 39 percent and 6 percent of patients, respectively. Nifedipine, a calcium flux antagonist, was effective in 80 percent of patients. Patients with normal coronary arteriograms who have clinical features suggestive of coronary arterial spasm should be considered for further investigation, including long-term electrocardiographic monitoring and provocative testing for spasm.

Coronary arterial spasm in angina at rest associated with transient ST-segment changes

In order to clarify the role of coronary arterial spasm in the pathogenesis of angina at rest, coronary arteriography was perforned during spontaneous chest pain or following intravenous administration of ergonovine maleate in 40 patients with angina at rest. Coronary vasospasm was demonstrated in 23 patients with ST-segment elevation during chest pain (group I), in 7 with ST-segment depression (group II), and in 4 with both ST-segment depression and elevation (group III). Complete spastic occlusion of the proximal or of the midportion of the left anterior descending artery was always associated with ST-segment elevation in anterior leads. In contrast, transient ST-segment depression in anterior leads was associated with diffuse narrowing of the left anterior descending artery with slow progression of the contrast medium, or complete occlusion of a small branch or of the distal segment of the left anterior descending artery. ST-segment elevation in inferior leads was associated with complete spastic occlusion or with significant spastic narrowing of the right coronary artery or of the circumflex artery. We conclude that coronary spasm can be demonstrated in a selected cohort of patients with angina at rest associated with transient ST-segment changes. In some cases the site and the severity of the spasm may produce varying degrees of ischemia, thus determining the direction of the ST-segment shift.

Contribution of dynamic vascular wall thickening to luminal narrowing during coronary arterial constriction

Available estimates of the ratio of wall thickness to luminal radius of human coronary arteries and certain geometrical assumptions were used to calculate the amounts of vascular smooth muscle shortening required to produce specific changes in luminal diameter for hypothetical "normal" and stenotic arteries. The results indicate that even modest mural thickening due to disease may act as a "lever" in translating physiologic degrees of medial smooth muscle shortening into critical luminal obstructions, providing the diseased segment maintains some pliability. The possibility of acute luminal occlusion occurring at stenotic sites as the result of "normal" vasomotion is illustrated. The appropriate use of the term coronary arterial "spasm" is discussed in light of these observations.

Increase in R-wave amplitude during transient epicardial injury (Prinzmetal type)

An increase in QRS amplitude with S-T elevation occurs during the acute phase of myocardial infarction, coronary ligation and variant angina. Ischemic conduction delay, postulated as the cause, has not been well characterized. Six patients with transient chest pain, S-T elevation and increase in R-wave voltage also displayed concomitant shift of the frontal QRS axis toward the locus of injury. Electrocardiographic considerations suggest that regional ischemic block, not true hemiblock as has been suggested, offers the most inclusive explanation, providing previously neglected clinical confirmation of experimental observations.

The provocation of coronary artery spasm

On the basis of the overall experience, the provocation of coronary artery spasm with ergonovine is thought to be a highly sensitive and specific test for coronary artery spasm in Prinzmetal's variant angina. In spite of occasional complications, in experienced hands the procedure is considered to be safe. The challenge remains to determine the value of this and other provocative interventions in assessing the role of spasm in other aspects of ischemic heart disease, particularly in patients with critical atherosclerotic lesions.

Coronary hemodynamic effects of ergonovine maleate in human subjects

The coronary hemodynamic effects of ergonovine maleate were examined in 15 patients with a chest pain syndrome not thought to be variant angina. Ergonovine was given intravenously in sequential doses of 0.05, 0.1 and 0.25 mg while measurements were made of systemic hemodynamic variables, coronary sinus blood flow and coronary arteriovenous oxygen difference at intervals during the protocol. Coronary arterial diameters were measured from the 35 mm cineangiogram. Despite an increase in myocardial metabolic demand, as estimated with the heart-rate-blood pressure product, there was no apparent increase in coronary vascular resistance. In addition, there was a significant widening of the coronary arteriovenous oxygen difference in five of the seven patients in whom it could be measured. However, neither chest pain nor ischemic electrocardiographic changes were evoked. Although ergonovine also produced a diminution in epicardial coronary arterial diameters, this effect was not sufficient to explain the absence of appropriate coronary vasodilation. These results suggest that ergonovine may limit the normal vasodilatory response of the arteriolar bed to increases in myocardial metabolic demand.

Beneficial effects of intravenous glyceryl trinitrate in a case of Prinzmetal angina

A case is described of the successful use of intravenous glyceryl trinitrate in controlling ischaemia-induced high-grade ventricular ectopic activity occurring in a patient during a Prinzmetal angina attack. The intravenous form of glyceryl trinitrate is probably more effective than the sublingual form in controlling arrhythmias arising during acute ischaemic episodes because of prompt delivery of the drug to the coronary circulation where vasodilation occurs. In addition,the ability to control the quantity and rate of drug delivery with an intravenous infusion offers distinct advantages in cases of coronary spasm occurring during situations such as coronary arteriography where it can be administered with careful electrocardiographic and haemodynamic monitoring.

Variant angina pectoris: investigation of indexes of sympathetic nervous system function

One thousand forty-five spontaneous episodes of S-T segment elevation were observed in three patients over a total of 72 days of continuous electrocardiographic monitoring. Eighty-nine percent of episodes were asymptomatic; chest pain tended to occur with episodes longer than 3 minutes, and ventricular ectopy occurred almost exclusively with symptomatic episodes. Nitroglycerin regularly relieved angina or S-T elevation, or both. Plasma and urinary catecholamines and their metabolites were normal. Episodes of variant angina were not associated with a generalized increase in sympathetic outflow because serum catecholamine levels at the onset and termination of the S-T abnormalities were not elevated. Controlled trials of propranolol showed no significant beneficial effect. Propranolol significantly increased the length of episodes of S-T elevation in one patient, increasing ventricular irritability. The overall course of variant angina was quite variable, with spontaneous and long-lasting remissions, necessitating cautions interpretation of clinical trials.

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

To elucidate the pathophysiologic mechanism of coronary arterial spasm, the hypothesis was examined that underlying alterations in sympathetic activity may account for this syndrome in some patients. Observations were directed to alterations in coronary arterial hemodynamics and the electrocardiogram. Spasm of the left anterior descending coronary artery produced a mean increase in coronary vascular resistance of 107 percent (P less than 0.05) in four patients in whom coronary sinus blood flow was measured with the thermodilution technique. The alpha adrenergic blocking agent phentolamine, given intravenously, acutely reversed coronary spasm and its clinical manifestations in eight patients and reduced coronary resistance. In four patients, administration of the long-acting oral alpha blocking agent phenoxybenzamine (20 to 80 mg/day) caused disappearance of symptoms during a follow-up period of 3 to 12 months. Transient prolongation of the corrected Q-T interval preceded spontaneous or ergonovine maleate-provoked coronary spasm in 11 patients with variant angina pectoris, whereas no significant change in the Q-T interval followed ergonovine administration in 27 control patients with atypical chest pain who did not have coronary spasm. T wave inversions in the resting electrocardiogram were normalized by isoproterenol infusion in one patient and by long-term phenoxybenzamine treatment in four patients with variant angina pectoris. These Q-T and T wave changes are analogous to those described with unilateral or asymmetric stellate ganglion stimulation in animals. These observations suggest that alterations in the sympathetic nervous system that are consistent with asymmetric stellate ganglion activity and transient alpha adrenergic receptor stimulation can presage the development of coronary arterial spasm in some patients with variant angina pectoris.

Prinzmetal's variant angina associated with subarachnoid hemorrhage: A case report

Prinzmetal's variant of angina occurred in a 48-year-old man who sustained two attacks of subarachnoid hemorrhage within 10 days. The first anginal pain started at the same time that the second cerebrovascular accident developed, but subsequent anginal episodes were not accompanied by other symptoms or signs that indicated new development of subarachnoid hemorrhage. Twelve days later, when nuchal rigidity was fairly improved, the episodes of chest pain ended. A vasospasm of the large coronary arteries--probably due to the derangement of the autonomic nervous system caused by subarachnoid hemorrhage--was presumed to contribute to the occurrence of the variant angina. Based on this case and on review of the literature, we propose that coronary arterial spasm is one of several causes of the cardiac changes seen in subarachnoid hemorrhage.

Exertional angina pectoris caused by coronary arterial spasm: effects of various drugs

In four patients with exertional angina induced by arm exercise, coronary arteriograms taken before, during and after the attack demonstrated that spasm appeared in the large coronary artery supplying the area of myocardium shown to be ischemic in the electrocardiogram during the attack. The spasm disappeared with subsidence of the attack after administration of nitroglycerin. Anginal attacks induced by treadmill exercise were not suppressed by propranolol, 60 mg orally, in two of the four patients. However, such attacks were suppressed in all patients by oral administration of diltiazem (90 mg, four patients) or nifedipine (20 mg, three patients) or intramuscular injection of phentolamine (0.2 mg/kg body weight, three patients). It is concluded that coronary arterial spasm can be induced by exercise and can cause exertional angina in some patients. Diltiazem and nifedipine, calcium antagonistic drugs, prevent spasm.

Treatment of variant angina pectoris with perhexilene maleate

Three patients with variant angina pectoris resistant to therapy with nitrates and propranolol were treated with perhexilene maleate. Two patients had normal coronary arteries with documented coronary artery spasm, while the third patient had a fixed coronary artery obstruction. In all three patients, attacks of variant angina pectoris disappeared following institution of therapy with perhexilene maleate. When the dose of this drug was decreased to 100 mg per day or less, symptoms reappeared in all patients. Reinstitution of therapeutic doses of perhexilene maleate once again resulted in complete control of symptoms. Perhexilene maleate is therefore a useful agent for the treatment of variant angina pectoris.

The effects of ergonovine maleate on coronary arterial size

Changes in coronary arterial size due to ergonovine maleate are described and quantitated in 90 patients--18 with typical angina pectoris, 56 with atypical chest pain, nine with variant angina pectoris, and seven heart transplant (allograft) recipients. We observed two angiographic changes in the diameter of coronary arteries: 1) spasm, which was characterized by occlusion or marked (greater than 85%) focal or diffuse vessel narrowing, or 2) relatively mild and diffuse vessel narrowing, which was interpreted as the normal pharmacologic response to the drug. Serial bolus injections of 0.05 mg, 0.10 mg and 0.25 mg of ergonovine maleate produced diffuse narrowing of the diameter of coronary arteries of 10 +/- 1.5%, 16 +/- 1.4% and 20 +/- 1.3% (mean +/- SEM), respectively, in the 72 patients with anginal syndromes who did not develop coronary spasm. The degree of coronary arterial narrowing was the same in heart transplant recipients and in patients with normally innervated hearts who did not develop coronary spasm. We believe the normal pharmacologic response to ergonovine maleate was due to a direct vasoconstrictor action of the drug; this action was independent of neural control extrinsic to the heart.

Role of large arteries in regulation of cerebral blood flow in dogs

Previous studies have demonstrated a significant pressure gradient from carotid artery to pial or middle cerebral arteries. This pressure gradient suggests that large cerebral arteries contribute to cerebral resistance. We have tested the hypothesis that large cerebral arteries contribute to regulation of cerebral blood flow during changes in blood gases and arterial pressure. Microspheres were used to measure brain blood flow in anesthetized dogs. Resistance of large cerebral arteries was estimated by determining the pressure gradient between common carotid and wedged vertebral artery catheters. Systemic hypercapnia and hypoxia dilated large cerebral arteries, and hypocapnia constricted large cerebral arteries. Resistance of large arteries was 0.6+/-0.1 (mean +/- SE) mm Hg per ml/min per 100 g during normocapnia. During hypercapnia and hypoxia, large artery resistance decreased significantly to 0.2 +/- 0.03 and 0.3 +/- 0.05, respectively. During hypocapnia large artery resistance increased significantly to 1.0 +/- 0.1. In other experiments, we found that large cerebral arteries participate in auto-regulatory responses to hemorrhagic hypotension. When arterial pressure was reduced from 110 to 58 mm Hg, autoregulation maintained cerebral blood flow constant, and resistance of large cerebral arteries decreased significantly from 1.0 +/- 0.2 to 0.6 +/- 0.1 mm Hg per ml/min per 100 g. In absolute terms, we calculated that 20-45% of the change in total cerebral resistance during these interventions was accounted for by changes in large artery resistance. These studies indicate that large cerebral arteries, as well as arterioles, participate actively in regulation of cerebral blood flow during changes in arterial blood gases and during autoregulatory responses to hemorrhagic hypotension.

ST-segment elevation during recovery from exercise. A new manifestation of Prinzmetal's variant angina

Four patients underwent exercise testing because of a history of pain in the chest; all four developed marked elevation of the S-T segment only during recovery after exercise. Three of the four patients showed ST-segment depression during exercise, but ST-segment elevation was absent until two or more minutes after cessation of exercise. ST-segment elevation after exercise was accompanied by hypotension in three patients and by ventricular arrhythmias in one. Subsequent coronary angiographic studies revealed normal or minimally diseased coronary arteries in two patients and significant coronary lesions in the other two. Review of the literature shows that contrary to the prevailing belief, over half of the patients with Prinzmetal's variant angina have electrocardiographic changes diagnostic of ischemia during exercise testing. Over half of the patients with abnormal findings on tests during exercise display ST-segment elevation as a manifestation of ischemia; however, delayed ST-segment elevation of the type seen in these four patients is distinctly uncommon, having previously been described in only three individual case reports. The pathophysiology of this response is uncertain but may relate to rapid alterations in the autonomic balance during recovery after exercise.

Rest angina with transient S-T segment elevation. Correlation of clinical features with coronary anatomy

In 44 consecutive patients with angina at rest associated with transient S-T segment elevation, clinical features were correlated with angiographic coronary anatomy. Patients were divided into three groups depending on the number of major vessels having greater than or equal to 70 per cent luminal narrowing: Group I = no or minimal disease (six patients); group II = single vessel disease (13 patients); and group III = multiple vessel disease (25 patients). The following features did not differ significantly among groups I, II or III: age, sex, risk factors, time from onset of episodes of pain at rest to study or arrhythmias during ischemic episodes. Patients in group III were more likely to have angina on effort (p less than 0.001) and an abnormal base line electrocardiogram (p less than 0.001) than patients in groups I or II. However, the absence of these features did not separate patients in group I from those in group II. In patients with angina at rest associated with transient S-T segment elevation, clinical features identify patients with multiple vessel disease but do not allow differentiation of patients with no or minimal coronary disease from patients with single vessel disease.

Coronary arterial spasm and Prinzmetal's variant form of angina induced by hyperventilation and Tris-buffer infusion

Vigorous hyperventilation was induced for five minutes immediately after a five-minute infusion of 100 ml of Tris-buffer (pH 10) in nine patients with Prinzmetal's variant angina. In eight of the patients, chest pain with ischemic changes in the electrocardiogram occurred during this procedure or within five minutes after it ended. Coronary arterial spasm appeared after the procedure and disappeared after the administration of nitroglycerin in all four patients in whom coronary cinearteriography was performed. This was evident both before and after the procedure and after sublingual administration of nitroglycerin (0.6 mg). The oral administration of 90 mg of diltiazem, a calcium antagonistic drug, two hours before, completely suppressed the attack induced by the procedure in all of the five patients who received this drug. We conclude that hyperventilation plus Tris-buffer infusion induces coronary arterial spasm and anginal attack in patients with Prinzmetal's variant angina and that diltiazem suppresses these reactions.

Angiographic evidence of myocardial squeezing accompanying tachyarrhythmia as a possible cause of myocardial infarction

The coronary arteriogram of a 52-year-old man with Basedow's disease and who was suffering from myocardial infarction following rapid atrial fibrillation, showed severe myocardial squeezing without organic stenosis. Angiographically, the functional obstructive lesion was always observed both at systole and diastole during atrial pacing, 150 beats per minute, and suggests that myocardial squeezing may be the cause of myocardial infarction following tachyarrhythmia.

Myocardial ischaemia in migraine sufferers taking ergotamine

Two cases of acute myocardial ischaemia precipitated by oral ergotamine therapy for migraine are described from patients with no previous history of ischaemic heart disease. The relevant literature is briefly reviewed.

The injury-vasospasm hypothesis of ischemic heart disease, revisited

The injury-vasospasm hypothesis of IHD was discussed in relation to coronary artery autoregulation and the anoxic-feedback mechanism. Observations in the recent literature, not usually attributed to spasm, were examined in light of this phenomenon. This includes reperfusion models of experimental AMI, the association of AMI with myocarditis, and findings in AMI and SCD as necrotic microlesions, prodromata, and epicardial arterial plaque rupture and hemorrhage. The disparity between the severity of coronary disease and the occurrence of the various types of IHD suggest that atherosclerosis itself does not precipitate attacks of chest pain. It was emphasized that plaque rupture due to spasm might help induce CAT. With exercise, the possible importance of the autoregulatory system was explored in the prevention and induction of AMI and SCD, and the improvement of AP. The role of spasm in IHD should be defined.

Provocative testing for coronary arterial spasm: rationale, risk and clinical illustrations

Two cases of Prinzmetal's variant angina are presented in which coronary spasm was documented by electrocardiographic evidence obtained in the coronary care unit during provocative testing with ergonovine maleate after the arteriographic demonstration of anatomically normal coronary arteries. The rationale and risks of provocative testing for spasm in patients with chest pain and anatomically normal coronary arteries are reviewed. The advantages of performing provocative testing in the coronary care unit after arteriography rather than in the catheterization laboratory during coronary arteriography are discussed.

Coronary heart disease in marathon runners

Six highly trained marathon runners developed myocardial infarction. One of the two cases of clinically diagnosed myocardial infarction was fatal, and there were four cases of angiographically-proven infarction. Two athletes had significant arterial disease of two major coronary arteries, a third had stenosis of the anterior descending and the fourth of the right coronary artery. All these athletes had warning symptoms. Three of them completed marathon races despite symptoms, one athlete running more than 20 miles after the onset of exertional discomfort to complete the 56 mile Comrades Marathon. In spite of developing chest pain, another athlete who died had continued training for three weeks, including a 40 mile run. Two other athletes also continued to train with chest pain. We conclude that the marathon runners studied were not immune to coronary heart disease, nor to coronary atherosclerosis and that high levels of physical fitness did not guarantee the absence of significant cardiovascular disease. In addition, the relationship of exercise and myocardial infarction was complex because two athletes developed myocardial infarction during marathon running in the absence of complete coronary artery occlusion. We stress that marathon runners, like other sportsmen, should be warned of the serious significance of the development of exertional symptoms. Our conclusions do not reflect on the possible value of exercise in the prevention of coronary heart disease. Rather we refute exaggerated claims that marathon running provides complete immunity from coronary heart disease.

Prinzmetal's angina

A 23-year-old man had Prinzmetal's variant angina. After strenuous exercise and isoprenaline infusion the electrocardiogram remained normal and the patient asymptomatic. Coronary angiography gave normal results which remained normal after administration of ergometrine. An injection of methacholine induced an attack.

Myocardial imaging in a patient with reproducible variant angina

A unique case is presented of variant angina pectoris with reproducible chest pain and S-T segment elevation in the immediate postexercise period and with normal coronary arteries. Coronary arterial spasm was deomnstrated with arteriography after intravenous administration of ergonivine maleate. Thallium-201 imaging during the pain reproducibility demonstrated malperfusion in the region supplied by the artery with documented spasm.

Clinical syndrome of variant angina with normal coronary arteriogram

We compared patients with variant angina (ST-segment elevation during pain) who had normal or near normal coronary arteriograms (Group 1) with 20 in whom variant angina occurred in the presence of obstructive coronary lesions (Group 2). A long history of nonexertional angina without angina of effort or previous infarction was the rule in Group 1, whereas recent-onset unstable angina preceded by effort angina and infarction predominated in Group 2 (P less than 0.001). Normal electrocardiograms at rest, with ischemic ST-segment elevation in the inferior leads, and ischemia-induced heart block and bradycardia, characterized Group 1, whereas abnormal electrocardiograms, ischemic involvement or fibrillation were more common in Group 2 (P less than 0.001). Variant angina with normal coronary arteriogram generally has a benign course and is probably unrelated to atherosclerosis.

Spectrum of coronary arterial spasm. Clinical, angiographic and myocardial metabolic experience in 29 cases

A relationship of coronary arterial spasm to variant angina pectoris, subendocardial ischemia, major ventricular arrhythmias and myocardial infarction has been demonstrated. In 29 patients, spasm was angiographically observed in normal-appearing coronary arteries (7 patients) as well as superimposed on various degrees of coronary atherosclerotic obstruction (22 patients). All patients experienced an atypical anginal syndrome;16 patients also experienced typical exertional angina. Coronary spasm appeared to be a major contributory factor in eight occurrences of myocardial infarction and in 11 incidents of ventricular tachycardia, ventricular fibrillation and heart block. Coronary spasm in the 29 cases was distributed in the following fashion: left main trunk, 6 cases; right main trunk, 12 cases; proximal left anterior descending artery, 13 cases; proximal circumflex artery, 1 case; distal left anterior descending artery, 1 case; and distal circumflex artery, 2 cases. In 5 cases coronary spasm was noted at multiple sites.

Coronary artery spasm: the effect of cardiovascular laboratory premedication practice

Eighty-four university cardiovascular laboratories responded to a questionnaire concerning premedication practice and observation of noncatheter-induced coronary artery spasm during routine coronary angiography. Half of the laboratories stated that they had not observed the phenomenon. The data suggest that premedication practice may account in part for the relative rarity of this phenomenon.