Acute coronary vasospasm secondary to industrial nitroglycerin withdrawal

A Black employee exposed to industrial nitroglycerin (NG) in an explosives factory presented with severe precordial pain. The clinical presentation was that of significant transient anteroseptal and anterolateral transmural myocardial ischaemia which responded promptly to sublingual isosorbide dinitrate. Despite being removed from exposure to industrial NG and receiving therapy with longacting oral nitrates and calcium antagonists, the patient continued to experience repeated attacks of severe retrosternal pain, although transient myocardial ischaemia was not demonstrated electrocardiographically during these episodes. Cardiac catheterization revealed cl normal myocardial haemodynamic system and selective coronary arteriography delineated coronary arteries free from any obstructive lesions. An ergonovine (ergometrine) maleate provocative test failed to elicit coronary artery spasm, although this was undertaken while the patient was on nitrate and calcium-blocker therapy. Clinical records of previous significant constrictive pericarditis (probably due to tuberculosis) with resultant abnormalities on the ECG complicated the diagnosis. Evaluation was further hindered by the known 'variant pattern' seen on the ECGs of members of the Black population. We postulate that this patient's clinical features were a direct result of severe vasospasm affecting' the left coronary artery; it is also strongly suggested that withdrawal from contact with industrial NG precipitated this potentially lethal coronary vaso. spasm. The role played by industrial NG in ischaemic heart disease is reviewed, as well as the importance of the 'normal variant pattern' in the assessment of cardiac disease in Black patients. As far as we are aware this is the first time that the use of the ergonovine maleate provocative test has been documented in the industrial NG withdrawal syndrome

Endomyocardial biopsy: A review of the literature

A review of the literature relating to endomyocardial biopsy (EMB) is presented. This is considered important at this time since EMB is being utilized with increasing frequency, particularly for the diagnosis of myocarditis. The development of the technique is briefly outlined. Emphasis is placed on the clinical application of EMB in the various primary cardiomyopathies (dilated, hypertrophic, restrictive, and obliterative), the infiltrative secondary cardiomyopathies (amyloidosis, sarcoidosis, hemochromatosis), myocarditis, as well as such conditions as adriamycin cardiotoxicity, cardiac transplant rejection, and Kawasaki disease. More controversial application of EMB in primary mitral valve prolapse (Barlow's syndrome), idiopathic ventricular arrhythmias, and the elucidation of the enigmatic finding of angina with angiographically normal coronary arteries is detailed. Experience with immunological and biochemical investigation of biopsy material, as well as with virus isolation and drug assays in the myocardium, is alluded to. Complications encountered with the procedure are also discussed, and its future role is contemplated.Articl

Angina pectoris and acute myocardial infarction due to slow-flow phenomenon in nonatherosclerotic coronary arteries: A case report

A 51 year-old White woman with angina pectoris and nonatheromatous coronary artery disease is presented. Cardiac catheterization demonstrated a 'slow-flow phenomenon' in the left coronary artery accompanied by severe angina pectoris and anterolateral ST-degment elevation and culminating in an acute nontransmural myocardial infarction. At repeat coronary arteriography, ergonovine maleate provocation proved negative. This patient is unique, since the previously documented 6 cases with this coronary cineangiographic response did not exhibit angina pectoris or ECG evidence of myocardial ischemia during the 'slow-flow phenomenon', and none was complicated by an acute myocardial infarction. Various aspects of the pathophysiology of angina pectoris in this patient, including the recently described 'reduced vasodilator reserve' concept, are briefly outlined.Articl