[Clinical and angiographic study and pathogenic mechanism of Prinzmetal's angina. Apropos of 31 cases]

31 patients presenting with Prinzmetal variant angina were divided into three groups according to their angiographic appearances. Group I comprised 9 patients with normal or coronary arteries with lesions less than 50% narrowing. Group II comprised 12 patients with single vessel disease. Group III comprised the other 10 patients with significant lesions on two or all three principal arteries. No clinical or electrocardiographical differences were found between the groups as to age, sex or the clinicapresentation of the chest pain. Most patients with normal or nearly normal coronary arteries had normal electrol cardiogrammes between attacjs (8 out of 9) and electrical changes mainly over the inferior wall (8 out of 9). Exercise electrocardiography reproduced ST elevation in 4 of the 9 patients but, in contrast to the patients in the other two groups, never ST depression. However, these features are not specific for patients in Group I as they were observed in 4 patients in the other two groups. Spontaneous or induced coronary spasm were observed in 27 patients, confirming its role as the mechanism of Prinzmetal angina, whatever the anatomical appearance of the coronary tree.

Coronary artery spasm--a case with fatal outcome

The case of a 45-year-old man with nocturnal angina and angiographically verified spontaneous spasm of the left anterior descending and left circumflex coronary arteries is described. The patient died suddenly one month after investigation, despite treatment with a beta-blocker and nitroglycerin. Other forms of pharmacological treatment should be tried in such patients.

[Methyl-ergometrin maleate test during coronary arteriography in spontaneous chest pain]

This coronary spasm provocation test with methyl-ergometrine maleate was carried out during coronary arteriography in 47 patients presenting with spontaneous chest pain. Coronary spasm was triggered in 16 cases, reproducing the chest pain in 11 patients, and accompanied by electrical changes in 15 cases, 12 subepicardial ischaemias and 3 subendocardial ischaemias. This test is not without danger to the patient as arrhythmias and conduction defects were recorded in 6 cases although the spasm was readily reversible on injection of intravenous glyceryl trinitrate. Of 7 patients with Prinzmetal variant angina, the test was positive 6 times, in three of which on pre existing severe organic lesions, so confirming the mechanism of this syndrome and the reliability of the test. Of 40 patients presenting with spontaneous chest pain, 10 had a positive test. In 2 of these cases the chest pain was subsequently observed with subepicardial ischaemic electrical changes, so confirming the screening value of this test. In the 7 cases where coronary spasm gave rise to electrical changes with or without pain, the logical diagnosis would appear to be spastic angina. In the 30 cases where the test was negative the subsequent outcome did not provide any proof in favour of a coronary origin of the chest pain.

Recurrence of Prinzmetal angina seven years following aortocoronary bypass surgery: a clinical and angiographic follow-up

A patient with Prinzmetal angina and ST segment elevation in the anterior ECG leads became asymptomatic after a 50% left anterior descending coronary artery stenosis was bypassed. However, seven years later Prinzmetal angina recurred but with ST segment elevation in the inferior ECG leads. Although the coronary bypass graft had remained patent, the proximal and distal left anterior descending coronary artery was occluded. No significant stenosis was present in the right coronary artery. Perhexiline maleate controlled his symptoms but when the drug was stopped because of side effects an acute inferior myocardial infarction occurred.

Variant forms of angina pectoris

3 patients with different clinical and electrocardiographic manifestations of coronary artery spasm are discussed. All 3 patients had anginal attacks at rest. In addition, 2 of these patients, who did not have significant preexisting narrowing of their coronary arteries, also had anginal pain related to exercise. During pain, 1 patient showed ST-segment elevation, the other ST-segment depression, while the third showed ST-segment depression shortly followed by ST-elevation on the electrocardiogram. At coronary angiography, spontaneous or induced spasm of one of the major coronary arteries could be demonstrated in all 3 patients. In 2 cases, sublingual nitroglycerin failed to completely relieve the spasm. This raises the question whether a residual stenosis after NTG conclusively proves a fixed organic narrowing. It is concluded that the clinical spectrum of spasm of the coronary arteries is wider than was originally reported by Prinzmetal and coworkers. Clinical and electrocardiographic manifestations are probably dependent on the site and severity of the spasm, which may cause different degrees of myocardial ischemia.

[Intimal coronary fibrous dysplasia and Prinzmetal's angina]

It is currently considered as exceptional for there to be arterial pathology other than atheroma in Prinzmetal angina. The authors have found five cases of coronary fibrous dysplasia in the literature. They add a case, in a woman, of intimal fibrous dysplasia diffusely involving the three main coronary vessels. Coronary arteriography showed that spasm of the right coronary artery was the cause of attacks with the clinical and electrocardiographic features of Prinzmetal angina. The whole coronary tree was otherwise normal angiographically and also macroscopically at autopsy. The dysplasia was only discovered by histological study of serial sections of the three coronary vessels. Histological examination showed no evidence of an atheromatous lesion. The authors place these coronary artery lesions within the general classification of arterial fibrous dysplasias. It remains hypothetical whether there is a relationship between the occurrence of spasm and this very special histological feature of the coronary artery wall.

[Short-term localized myocardial ischaemia and its consequences in Prinzmetal angina pectoris (author's transl)]

In a 45-year-old female patient with Prinzmetal angina pectoris coronary angiograms and a 201thallium scintigram were performed during an ergotamine-induced episode of angina. The spontaneous and the ergotamine-induced attacks were characterized by transient ST elevation in the posterior wall ECG leads. The coronary angiogram during the attack showed spasm of the circumflex branch of the left coronary artery. In the 201thallium scintigram a large defect in myocardial thallium uptake was noticed in the posterior wall of the left ventricle. Angina and ECG abnormalities disappeared within 4 minutes. However, the scintigraphic defect disappeared only after 6 hours. The slow recovery of myocardial thallium uptake is thought to represent an alteration of the myocardium after a brief 4 minute interruption of regional coronary arterial blood flow. The diagnostic approach in patients with Prinzmetal angina is discussed.

Angiographic and pathologic correlations in Prinzmetal variants angina

The coronary-arteriographic and pathologic findings in a case of Prinzmetal's angina are reported. Right coronary arteriograms performed in the absence of pain showed only minor stenotic changes, whereas those performed during an anginal attack revealed a spastic occlusion involving almost the entire vessel. Anatomic examination revealed obstructive lesions of the right coronary artery, more pronounced at the site where spasm had started, due to concentric atherosclerotic thickening of the inner wall, whereas the elastic fibers and the muscular ring of the tunica media were preserved. These findings suggest (1) the need for great caution before assuming on purely angiographic bases that spasm may affect a normal coronary artery and (2) the possibility that spasm occurs in a markedly diseased and stenotic segment of a coronary artery as long as the contractile tissue of the tunica media is preserved.

[Current indications of coronary arteriography in coronary artery disease (with the exception of acute myocardial infarction) (author's transl)]

The indications of coronary arteriography have multiplied in recent years. Therapeutic indications have followed knowledge of the good results of revascularisation surgery. Initially limited to severe stable angina improved little or not at all by major anti-angina agents, they have been extended, in the view of many, to include various types of unstable angina where, in addition to the symptomatic improvement obtained, an attempt is made to decrease the incidence of myocardial infarction and of long term mortality. Indications relative to determination of the extent of disease may be preventive: the fear of severe coronary lesions on the basis of effort test results, the fear of a second infarction immediately following a primary lesion, or as a virtually routine examination in young individuals in order to better assess the degree of disease and to guide treatment. Diagnostic indication should be rare.

Alternans of the ST segment in Prinzmetal's angina

Alternans of the elevated ST segment (STEA) was found in 8 of 21 patients (38%) with Prinzmetal's variant angina. In addition to STEA, all eight patients had varying cardiac arrhythmias: multiple premature ventricular depolarizations in eight, ventricular tachycardia in five, and ventricular fibrillation in three. There was no consistent temporal relationship between the occurrence of STEA and the cardiac arrhythmias. Alternans occurred during periods when no arrhythmias were present. All eight patients underwent coronary angiography. Spontaneous coronary artery spasm was documented angiographically in three patients including two who had minimal or no coronary atherosclerotic disease. Six patients had severe, fixed, occlusive coronary artery disease. Possible mechanisms for STEA include: 1) failure of regions of myocardium to depolarize on alternate beats due to variation in conduction and refractoriness between ischemic and nonischemic zones of myocardium, and 2) electrical alternans of the transmembrane action potential during phase 2 and 3 (repolarization) caused by changes in the rate and extent of electrolyte transfer across cell membranes during ischemia. It is postulated that STEA is an electrocardiographic sign in the surface ECG of a dysequilibrium of refractory periods during ischemia and reflects an unstable electrical state of the myocardium.

[Prinzmetal's angina. Histological study of peroperative coronary specimens. Apropos of 2 cases]

The results of histological examination of two coronary artery biopsy specimens removed at operation are presented. There were unusual findings, especially of a highly cellular and oedematous fibroblastic endarteritis, of the lack of calcification, and of the presence of marked medial sclerosis. These unusual histological findings are the result of solitary variable stenoses of the coronary arterial tree, and very different from the histological findings in the atheromatous lesions which are usually found when Prinzmetal's angina is super-imposed on lesions which are multiple and diffuse.

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.

[Concomitant Prinzmetal angina and coronary angina. Angiographic study in 13 patients (author's transl)]

Is coronary spasm the explanation for the paroxysmal myocardial ischaemia of Prinzmetal angina? Although considered adventurous two or three years ago, this hypothesis has been supported by the publication of approximately 15 cases in which the cause and effect relationship seemed to be proven by spasm seen on coronary arteriography at the same time as a typical attack. The authors report 13 cases of this type (the first of which was published in 1972). Spasm occurred in a normal coronary system in 3 cases, whilst in 2 cases there were only non-stenotic plaques of atheroma. In 8 cases, spasm occurred at the site of or distant from a significant atheromatous lesion. In 8 cases, spasme involved the right coronary whilst in 3 cases the A.I.V. was affected and in 2, two of the three main coronary trunks. In the light of their experience, the authors stress two points: --in many cases, nitroglycerine alone is not sufficient to relieve the spasm, and only the in situ injection of papaverine had a constant effect; --it is essential to opacify both coronary systems during a typical attack in order to obtain proof of spasm.

Technetium-99m stannous pyrophosphate myocardial scintiphotos in patients admitted to rule out acute myocardial infarction

Technetium-99m stannous pyrophosphate (Tc-PYP) cardiac scintiphotos were performed on 101 of 221 patients admitted to the Coronary Care Unit to rule out acute myocardial infarction (AMI). Criteria were defined for the diagnosis of AMI, variant angina and unstable angina. 42 patients were diagnosed as having had an AMI. 22 patients had transmural and 20 patients had nontransmural AMI. 40 of the 42 patients with AMI (95%) had positive scintophotos; 2 (5%) had negative scintiphotos. 59 patients did not have an AMI; (97%) had negative scintiphotos. Four of these 59 patients had variant angina; all had negative scintiphotos. Seven of these 59 patients had unstable angina; 2 had positive scintiphotos. Tc-PYP scintiphotos have high sensitivity and specificity and are accurate in correctly classifying patients as having or not having AMI.

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.