'Angina' and normal coronary arteriograms: a follow-up study

Evaluation of serum sST2 and sCD40L values in patients with microvascular angina

OBJECTIVES

Coronary microvascular dysfunction plays a major role in the pathogenesis of microvascular angina (MVA). Along with endothelial dysfunction, microvascular atherosclerosis and inflammation seem to contribute to the development of coronary microvascular dysfunction. Serum soluble ST2 (sST2) and serum soluble CD40 ligand (sCD40L) are two biomarkers associated with inflammation and atherosclerosis. The aim of this study was to investigate the role of these biomarkers in the pathogenesis of MVA and determine their possible association with coronary microvascular dysfunction.

METHODS

A total of 152 patients were included in the study. Ninety-one patients with MVA {median age 56 years (40-79), of which 55 are women} and sixty-one controls {median age 52 (38-76), of which 29 are women} were included in the study. Serum concentration of sST2 and sCD40L were measured with a commercially available ELISA kit.

RESULTS

Serum sST2 (median 13.6 ng/ml; interquartile range (IQR), 3.5-63.8 ng/ml vs median 10.6 ng/ml; IQR, 2.9-34.2 ng/ml, p < 0.0005) and sCD40L (median 5.3 ng/ml; IQR, 0.5-20.6 ng/ml vs median 2.2 ng/ml; IQR, 0.7-10.8 ng/ml, p < 0.0005) were significantly higher in patients with MVA compared to controls. Analysis of the associations between these biomarkers and potential contributors of MVA revealed that serum sST2 showed a positive correlation with LDL-cholesterol (r = 0.19, p = 0.016) and serum sCD40L concentrations correlated positively with hs-CRP (r = 0.22, p = 0.005). In logistic regression analysis, sCD40L and hs-CRP but not sST2 were found to be significantly associated with MVA.

CONCLUSION

Higher serum concentrations of sST2 and sCD40L in MVA patients may be associated with inflammatory activation and coronary microvascular dysfunction. Larger studies are required for understanding their role in the pathogenesis of inflammatory and possibly fibrotic process in MVA patients.

Coronary endothelial dysfunction in non-obstructive coronary artery disease: Risk, pathogenesis, diagnosis and therapy

Up to half of patients with signs and symptoms of stable ischemic heart disease have non-obstructive coronary artery disease (NoCAD). Recent evidence demonstrates that two-thirds of patients with NoCAD have demonstrable coronary endothelial dysfunction represented by microvascular or diffuse epicardial spasm following acetylcholine challenge. Patients with coronary endothelial dysfunction are recognized to have significant health services use and morbidity as well as increased risk of developing flow-limiting coronary artery disease and myocardial events, including death. Currently, there are few centers that test for this etiology owing to lack of knowledge, limited evidence for treatment options and invasive diagnostic strategies. This article reviews the pathophysiology, epidemiology, diagnosis and treatment of coronary endothelial dysfunction as a subgroup of NoCAD.

Microvascular angina and the continuing dilemma of chest pain with normal coronary angiograms

Since initial reports over 4 decades ago, cases of patients with angina-like chest pain whose coronary angiograms show no evidence of obstructive coronary artery disease and who have no structural heart disease continue to be a common occurrence for cardiologists. Many features of this patient population have remained constant with successive reports over time: a female predominance, onset of symptoms commonly between 40 and 50 years of age, pain that is severe and disabling, and inconsistent responses to conventional anti-ischemic therapy. Because patients may have had abnormal noninvasive testing that led to performance of coronary angiography, investigators have sought to show an association of this syndrome with myocardial ischemia. Abnormalities in coronary flow and metabolic responses to stress have been reported by several groups, findings consistent with a microvascular etiology for ischemia and symptoms, but others have questioned the presence of ischemia, even in patients selected for abnormal noninvasive testing. Despite considerable efforts by many groups over 4 decades, the syndrome remains controversial with regard to pathophysiology, diagnosis, and management.

How often does the gut cause anginal pain?

Gastrointestinal disease imitates angina quite commonly and the oesophagus is usually responsible, both in patients presenting as emergencies and also in those who have been extensively investigated for apparent angina. A questionnaire study of 22 patients with oesophageal spasm and 15 patients with coronary artery disease failed to show any feature that discriminates reliably between these groups.

Is there an association between left bundle branch block and coronary slow flow in patients with normal coronary arteries?

Slow flow in angiographically normal coronary arteries is not a rarely seen problem. It is unknown whether it is related with conduction disorders. In this study we investigated the frequency of conduction disorders in patients with normal coronary artery and slow flow. The study included 36 (22 female; mean age 63 +/-11 years) patients who have normal coronary arteries and slow flow in coronary angiography. Patients' 12-lead electrocardiograms were analyzed for the presence of bundle branch block. Twenty-two of 36 patients (61%) demonstrated left bundle branch block. Twelve patients (33%) had normal intraventricular conduction. Only 2 of 36 patients (6%) had right bundle branch block. Microvascular disease has been implicated in coronary slow flow. However, according to the results of this study there is a close association between especially left bundle branch block and coronary slow flow. A causal relation should be sought between them with future studies.

Slow coronary flow: a distinct angiographic subgroup in syndrome X

Patients evaluated for chest pain with angiographically normal coronary arteries are usually labelled syndrome X. A portion of these patients may not have a cardiac cause for their symptoms. The authors aimed to study a subset within this group who showed the phenomenon of slow coronary flow (SCF) as evidenced by a slow antegrade progression of the dye on the coronary arteriogram to see if this could be used as a marker of myocardial ischemia. This observational study included 207 patients being evaluated for suspected coronary artery disease and found to have normal coronary angiograms. SCF was seen in 49 of these patients (23.7%) while the remaining 158 (76.3%) had normal coronary flow (NCF), as detected by the corrected thrombosis in myocardial infarction (TIMI) frame count method (TIMI frame count more than 2 SD of normal). Forty of the 49 patients (82%) in the SCF group had classical angina as compared with only 51 of the 158 patients (32%) in the NCF group (p<0.01). Also, a definitively positive exercise test was observed more commonly in the SCF group than in the NCF group (71% vs 42%, p < 0.01). The authors conclude that SCF patients constitute a definite subset within the wide spectrum of syndrome X and that the phenomenon of SCF could be used as a marker for myocardial ischemia.

Randomized trial of sertraline in patients with unexplained chest pain of noncardiac origin

BACKGROUND

Between 10% and 30% of patients with symptoms similar to angina and sufficient to justify cardiac catheterization are found to have normal coronary angiograms. Treatment of patients with chest pain with no apparent cardiac cause is a major clinical problem. Our hypothesis was that sertraline would reduce the severity of pain in patients with chest pain of noncardiac origin.

METHODS AND RESULTS

This was a single-site, double-blind, placebo-controlled study of the efficacy, tolerability, and safety of sertraline in the treatment of noncardiac chest pain in outpatients. Thirty patients were enrolled in the study. After 1 week of single-blind placebo washout, patients were randomly assigned in a double-blind fashion either to drug or placebo. The Beck Depression Inventory was administered at baseline and at completion of study. Daily pain diaries (visual analogue scale, rating pain on a scale of 1 to 10) were selfadministered and evaluated at baseline and at follow-up visits. Statistical measures were performed with an intention-to-treat approach. Patients who received sertraline over the course of the study showed a statistically significant reduction in pain compared with those who were receiving placebo.

CONCLUSIONS

The use of sertraline in patients with noncardiac chest pain produced clinically significant reduction of daily pain. These results suggest the need for further studies of the efficacy and tolerability of sertraline and other selective serotonin reuptake inhibitors in the long-term management of noncardiac chest pain.

17-beta-Estradiol therapy lessens angina in postmenopausal women with syndrome X

OBJECTIVES

We sought to investigate the hypothesis that estrogen replacement therapy ameliorates symptoms in postmenopausal women with syndrome X.

BACKGROUND

Syndrome X (angina pectoris, positive findings on exercise electrocardiography and normal results on coronary angiography) frequently occurs in menopausal women. This observation, in conjunction with the known vasoactive properties of estrogens, suggests that estrogen depletion may contribute to the pathogenesis of syndrome X in some women.

METHODS

Twenty-five postmenopausal patients with syndrome X completed a double-blind, placebo-controlled study of the effect of 17-beta-estradiol cutaneous patches (100 micrograms/24 h) on the frequency of chest pain and on exercise tolerance. Patients were randomly assigned to receive either placebo or 17-beta-estradiol patches for 8 weeks and were then crossed over to the other treatment.

RESULTS

During the placebo phase, patients had a mean of 7.3 episodes of chest pain/10 days. A reduction to 3.7 episodes/10 days was observed during the 17-beta-estradiol phase (p < 0.05). No significant differences were observed between the effects of 17-beta-estradiol and placebo on exercise duration or the results of other cardiologic investigations.

CONCLUSIONS

Estrogen replacement reduces the frequency of chest pain and may be a useful new therapeutic option for treating postmenopausal women with syndrome X.

Cardiovascular syndromes X, endothelial dysfunction and insulin resistance

Cardiac Syndrome X (microvascular angina) and the more recently described metabolic Syndrome X (an epidemiological association between insulin resistance and atheroma, dyslipidaemia, and hypertension) may have more in common than the chance of their common sobriquet, in view of evidence that microvascular angina too is characterised by insulin resistance and endothelial dysfunction. The implications are discussed.

Dipyridamole technetium-99m Sestamibi imaging in the diagnosis of syndrome X

In a middle-aged woman with anginal chest pain and a normal-appearing angiogram, dypiridamole technetium-99m Sestamibi scintigraphy, a noninvasive method, provided the diagnosis of syndrome X and was used in follow-up to monitor the course of disease.

Coronary flow reserve and oesophageal dysfunction in syndrome X

The relative prevalence of abnormalities of coronary flow reserve and oesophageal function was ascertained in 32 syndrome X patients with typical angina chest pain, a positive exercise test, and normal coronary arteries. Coronary flow reserve in response to a hyperaemic dose of papaverine was measured using an intracoronary Doppler catheter positioned in the left anterior descending coronary artery. An abnormal coronary flow reserve was defined as being < 3.0. Patients were investigated for oesophageal dysfunction by manometry and 24-hour pH monitoring. Thirteen patients had an impaired coronary flow reserve (group 1) and 19 patients had a normal flow reserve (group 2). Eight of the 13 group 1 patients (62%) and 13 of the 19 group 2 patients (68%, p = NS) had evidence of oesophageal dysfunction on either manometry or pH studies. Therefore, a total of 26 (81%) syndrome X patients had either an abnormality of coronary flow reserve or oesophageal dysfunction suggesting that chest pain in these patients may be due to myocardial ischaemia or oesophageal dysfunction, thus confirming the heterogeneous nature of this syndrome. The prevalence of oesophageal abnormalities was independent of any abnormalities of coronary flow reserve.

Syndrome X--angina and normal coronary angiography

It is clear that angina pectoris with normal coronary arteries is a heterogeneous and ill-defined syndrome that encompasses different pathogenic entities. Differences in patient selection and in definition of 'syndrome X' has made comparison between different study groups rather difficult. Two decades of investigations have not revealed a specific cause of this syndrome. There is now a general belief that syndrome X probably encompasses several pathophysiological disease entities and the mechanisms involved in syndrome X remain to be fully elucidated.

Breathlessness in microvascular angina

In patients with microvascular angina (MA), there is some evidence from studies of plethysmography, that there are widespread microvascular abnormalities. In addition to exertional chest pain, all these patients complain of breathlessness, with no evidence of airways obstruction or resting left ventricular dysfunction. Progressive exercise testing was performed in 12 age and sex matched controls and 12 patients (three males), in whom the diagnosis of MA was established on the basis of exertional chest pain, abnormal thallium scans, and an attenuated myocardial flow response to a vasodilator challenge, with angiographically entirely normal epicardial vessels. Symptom limited exercise was performed with on line ventilation and expired gas analysis, measuring minute ventilation, oxygen consumption and carbon dioxide production and arterial blood gas values using a transcutaneous system. Anaerobic threshold was calculated by curve fitting a plot of oxygen consumption against carbon dioxide production. Compared to controls (49.7 +/- 7.3 SD% predicted maximum VO2) in patients with MA, the anaerobic threshold was reduced (41.6 +/- 5.82; P < 0.02) although still within accepted normal limits. Maximal (symptom limited) oxygen consumption, as a percentage of predicted, was reduced 60.73 +/- 16.51 compared to 87.21 +/- 5.2 (P < 0.003). The ventilatory response (VE/VCO2 l l-1 CO2 output) was significantly increased in the MA patients compared to controls (35.9 +/- 8.01 and 27.5 +/- 3.08, respectively; P < 0.02).(ABSTRACT TRUNCATED AT 250 WORDS)

EVALUATION OF NON-CARDIAC CHEST PAIN

A series of five cases of non-cardiac chest pain is being reported. In all cases, a detailed cardiac work up excluded coronary artery disease (CAD). Upper gastro-intestinal endoscopy was found to be useful. Gastro esophageal reflux disease (GERD) was diagnosed in three cases. The diagnosis of esophageal disease was clinical in the other two. All patients responded well to further treatment and have been followed up for six months to two years.

Imipramine in patients with chest pain despite normal coronary angiograms

BACKGROUND

Ten to 30 percent of patients undergoing cardiac catheterization because of chest pain are found to have normal coronary angiograms. Because these patients may have a visceral pain syndrome unrelated to myocardial ischemia, we investigated whether drugs that are useful in chronic pain syndromes might also be beneficial in such patients.

METHODS

Sixty consecutive patients underwent cardiac, esophageal, psychiatric, and pain-sensitivity testing and then participated in a randomized, double-blind, placebo-controlled three-week trial of clonidine at a dose of 0.1 mg twice daily (20 patients), imipramine at a dose of 50 mg nightly with a morning placebo (20 patients), or placebo twice daily (20 patients); this treatment phase was compared with an identical period of twice-daily placebo for all patients (placebo phase).

RESULTS

Thirteen (22 percent) of the 60 patients had ischemic-appearing electrocardiographic responses to exercise, 22 of the 54 tested (41 percent) had abnormal esophageal motility, 38 of 60 (63 percent) had one or more psychiatric disorders, and 52 of 60 (87 percent) had their characteristic chest pain provoked by right ventricular electrical stimulation or intracoronary infusion of adenosine. During the treatment phase, the imipramine group had a mean (+/- SD) reduction of 52 +/- 25 percent in episodes of chest pain, the clonidine group had a reduction of 39 +/- 51 percent, and the placebo group a reduction of 1 +/- 86 percent, all as compared with the placebo phase of the trial. Only the improvement with imipramine was statistically significant (P = 0.03). Repeat assessment of sensitivity to cardiac pain while the patients were receiving treatment showed significant improvement only in the imipramine group (P = 0.01). The response to imipramine did not depend on the results of cardiac, esophageal, or psychiatric testing at base line, or on the change in the psychiatric profile during the course of the study, which generally improved in all three study groups.

CONCLUSIONS

Imipramine improved the symptoms of patients with chest pain and normal coronary angiograms, possibly through a visceral analgesic effect.

Long-term follow-up of patients initially diagnosed with syndrome X

The clinical course of 30 patients (27 women and 3 men) diagnosed with syndrome X (angina pectoris, positive exercise test and normal coronary arteries) was evaluated during 5-year follow up. Patients were divided at the control examination into 2 groups according to the median value of the heart rate/blood pressure product variation from rest to the first stage of a modified Bruce protocol, as follows: group 1 < or = 1,050 (n = 15) and group 2 > 1,050 mm Hg x beats/min (n = 15). All patients were followed at 6-month intervals during a mean follow-up of 60 +/- 8 months. During follow-up, chest pain was unchanged in 20 patients, decreased in severity and frequency in 9 (7 in group 1, and 2 in group 2), and disappeared in 1 in group 2; 3 patients in group 1 had prolonged episodes of anginal chest pain (> 30 minutes) that needed hospitalization. In group 2, 7 patients developed systemic hypertension, 4 had a progression of exercise-induced left bundle branch block to constant left bundle branch block, and 4 continued to develop rate-dependent block during exercise, but at a reduced heart rate. In the latter 8 patients, left ventricular ejection fraction at rest during follow-up decreased significantly from 61 +/- 6% to 51 +/- 8% (p < 0.02).(ABSTRACT TRUNCATED AT 250 WORDS)

Anginal pain of esophageal origin: clinical presentation, prevalence, and prognosis

Since 1768, when Heberden recognized a relationship of angina pectoris with eating, the close resemblance between angina-like pain of esophageal and cardiac origin has led to diagnostic confusion, with the role of the esophagus being, in turn, over- and underemphasized as a cause of symptoms. Although the classic features of angina do not distinguish the origin of the pain, certain other symptoms may identify esophageal pain. These include an inconsistent correlation of exercise with pain, periods of prolonged remission, provocation of pain by posture, association with other esophageal symptoms, relief by antacids, radiation of pain down the right arm and into the back, occurrence of pain at night, continuation of pain as a background ache, and relief from nitroglycerine delayed by 10 minutes or longer. However, while certain symptoms may alert the clinician to the possibility that angina-like pain is due to esophageal disease, no single symptom or combination of symptoms is infallible; there is no alternative to careful assessment. Esophageal disease accounts for the greatest number of patients with chest pain of unknown origin. The prevalence of angina-like esophageal pain in unselected emergency admissions with suspected myocardial infarction is 10-20%. Approximately one third or more of patients with angina and normal coronary arteries have esophageal problems. We have followed patients with angina-like esophageal pain for 9 years. Although prognosis remains good, confirming the original noncardiac diagnosis, greater than 80% of patients continue to have chest pain of undiminished intensity, and half are limited in their ability to work. Reassurance appeared to have one beneficial result: Patients were less likely to consult a physician after a positive diagnosis had been made.

Twenty-four-hour esophageal pH monitoring: the most useful test for evaluating noncardiac chest pain

STUDY OBJECTIVE

To compare the diagnostic capabilities of traditional esophageal tests (manometry and provocative testing with acid and edrophonium) and 24-hour esophageal pH monitoring in identifying an esophageal cause of chest pain.

DESIGN

A prospective study of 100 consecutive patients referred by cardiologists to the esophageal laboratory for evaluation of esophageal causes of chest pain.

SETTING

Tertiary-referral university hospital.

METHODS

Esophageal manometry performed with 10 wet swallows of water. Acid perfusion (0.1 N hydrochloric acid) and edrophonium (80 micrograms/kg intravenously) tests were placebo-controlled with a positive study defined as replication of typical chest pain. Esophageal pH monitoring identified (1) abnormal acid exposure times in the upright, supine, or combined position, and (2) correlation between symptoms and acid reflux, i.e., symptom index. The esophagus was identified as "probably" contributing to chest pain only if the acid or edrophonium test was positive or if there was a positive correlation between symptoms and acid reflux during pH monitoring.

RESULTS

Esophageal manometry was abnormal in 32 patients (32%), but patients were asymptomatic during the study. The acid perfusion test was positive in 18 of 95 patients (19%), and the edrophonium test was positive in 15 of 78 patients (19%). Abnormal acid exposure times were found in 48 patients (48%). Of the 83 patients with spontaneous chest pain during 24-hour pH testing, 37 patients (46%) had abnormal reflux parameters and 50 patients (60%) had a positive symptom index (mean positive score 56%, range 6% to 100%).

CONCLUSIONS

Acid reflux is a common and potentially treatable cause of noncardiac chest pain. Traditional esophageal tests usually miss this diagnosis. Twenty-four-hour esophageal pH monitoring with symptom correlation is the single best test for evaluating patients with noncardiac chest pain.

Acid perfusion test and 24-hour esophageal pH monitoring with symptom index. Comparison of tests for esophageal acid sensitivity

The acid perfusion (Bernstein) test and esophageal pH monitoring are the two most popular tests for identifying esophageal acid sensitivity in difficult cases of reflux disease. Therefore, we prospectively compared these test results in 75 consecutive noncardiac chest pain patients who had both an acid perfusion test and chest pain during 24-hr pH testing. A positive acid perfusion test was defined by the replication of the patient's typical chest pain twice by the acid infusion. Esophageal pH testing identified abnormal amounts of acid reflux and correlated symptoms with acid reflux--the "symptom index." Fifteen patients (20%) had a positive acid perfusion test while 45 patients (59%) had a positive symptom index (range 6-100%). Only 9/34 (26%) patients with abnormal reflux had a positive acid perfusion test. Although it had excellent specificity (83-94%), the acid perfusion test had poor sensitivity (32-46%) when compared to the symptom index regardless of the percent positive cutoff level. The best positive predictive value for the acid perfusion test was 87%, but this occurred when the test sensitivity was 32%. Modifying the end point of a positive acid perfusion test to include heartburn improves the sensitivity (52-67%) while markedly compromising specificity and positive predictive value. Thus, esophageal pH monitoring correlating symptoms with acid reflux is superior to the acid perfusion test for identifying an acid sensitive esophagus in patients with noncardiac chest pain.

Syndrome X and hyperventilation

The cardiorespiratory responses to exercise and forced hyperventilation were measured in 17 unselected patients with syndrome X (angina, positive exercise test, normal coronary arteriogram, no other cardiovascular disease) and compared with those in 15 healthy subjects. Forced hyperventilation produced hypocapnia and metabolic alkalosis but no chest pain or electrocardiographic change. Patients with syndrome X showed reduced maximum oxygen consumption with an increased respiratory exchange ratio at peak exercise, confirming that exercise was limited by skeletal muscle perfusion--and thus that the increase in cardiac output with exercise is limited in syndrome X as in heart failure. Arterial carbon dioxide tension (PCO2) homoeostasis during exercise was normal but the ventilatory cost of carbon dioxide excretion was increased in syndrome X (as in heart failure). End tidal PCO2 measurements correlated only poorly with arterial PCO2 in individual patients with syndrome X, providing a possible explanation for previous reports, based on end tidal PCO2 of inappropriate hyperventilation. Patients with syndrome X did not show inappropriate hyperventilation but they did show hyperventilation that was appropriate to maintain normal arterial PCO2 in the face of reduced cardiac reserve.

Prospective study on prevalence of esophageal chest pain in patients referred on an elective basis to a cardiac unit for suspected myocardial ischemia

The prevalence of esophageal chest pain was studied prospectively in patients referred on an elective basis to a cardiac unit for suspected myocardial ischemia. A group of 248 consecutive patients without previously documented heart disease was admitted for elective diagnostic coronary angiography. The clinical history classified 185 patients as having anginal pain and the coronary angiogram was normal in 48 of them. In 37 of these 48 patients full esophageal testing was performed including 24-hr intraesophageal pH and pressure recordings with indication of chest pain episodes as well as a number of esophageal provocation tests, ie, acid perfusion, edrophonium stimulation, balloon distension, and ergonovine stimulation, all performed under continuous esophageal manometric and electrocardiographic monitoring. In 19 of these 37 patients, the familiar chest pain could be reproduced by esophageal provocative testing without ischemic ST-T segment alterations; six of these 19 patients had also a positive 24-hr pH and pressure recording. These data strongly suggest an esophageal origin of chest pain in half the patients with typical angina and a normal coronary angiogram.

Follow-up study of morbidity in patients with angina pectoris and normal coronary angiograms and the value of investigation for esophageal dysfunction

A postal questionnaire was used to assess the symptoms, use of medical facilities, and employment status of patients with angina pectoris and normal coronary angiograms following cardiac catheterization. In a retrospective study of 187 patients, 66 had left ventricular dysfunction demonstrated by abnormal regional wall motion and 121 had normal left ventricular function. At follow-up twelve to forty-six months following catheterization, 89% with left ventricular dysfunction and 82% with normal ventricular function had continued to experience chest pain. There was no significant change in the admission rate to hospital because of chest pain or the proportion of patients who were working, after catheterization as compared with before, in either group. Some patients with left ventricular regional wall motion abnormalities appeared to have progressive left ventricular dysfunction. In a prospective study of 63 patients, detailed investigation of esophageal function was performed. Twenty-two patients had left ventricular wall motion abnormalities. The majority of the 41 patients with normal left ventricular wall motion had esophageal abnormalities that were treated appropriately. At follow-up six to twenty-four months following catheterization significantly fewer patients with normal left ventricular function continued to experience chest pain compared with those with left ventricular dysfunction. Following catheterization the hospital admission rate fell significantly and the proportion of patients working increased significantly in the group with normal left ventricular function. The hospital admission rate and employment status of patients with left ventricular dysfunction did not change significantly following angiography. These findings suggest, therefore, that investigation for and treatment of esophageal dysfunction should be performed in patients with angina pectoris, normal coronary angiograms, and normal left ventricular function.

Syndrome X

The problem of anginalike chest pain with normal coronary arteriographic findings is briefly reviewed. This common clinical presentation (ca. 20% of patients investigated by coronary arteriography) is usually due to noncardiac causes (e.g., thoracic root or esophageal pain) but may represent myocardial ischemia attributable to reduced coronary dilator capacity downstream from the epicardial vessels and of unknown pathogenesis--Syndrome X (? less than 0.1% of such patients).

Chest pain: relationship of psychiatric illness to coronary arteriographic results

Seventy-four patients with chest pain and no prior history of organic heart disease were interviewed with a structured psychiatric interview immediately after coronary arteriography. The majority of patients with both negative and positive coronary angiographies had undergone previous exercise tolerance tests, but the patients with angiographic coronary artery disease were significantly more likely to have had positive results on a treadmill test. Patients with chest pain and negative coronary arteriograms were significantly younger; more likely to be female; more apt to have a higher number of autonomic symptoms (tachycardia, dyspnea, dizziness, and paresthesias) associated with chest pain, and more likely to describe atypical chest pain. Patients with chest pain and normal coronary arteriographic results also had significantly higher psychologic scores on indices of anxiety and depression and were significantly more likely to meet criteria of the Diagnostic and Statistical Manual of Mental Disorders, third edition, for panic disorder (43 percent versus 6.5 percent), major depression (36 percent versus 4 percent), and two or more phobias (36 percent versus 15 percent) than were patients with chest pain and a coronary arteriography study demonstrating coronary artery stenosis.

Continuous recording of coronary sinus oxygen saturation during atrial pacing in patients with coronary artery disease or with syndrome X

Coronary sinus oxygen saturation was measured continuously during incremental atrial pacing in 34 patients undergoing cardiac catheterisation. In eleven patients with normal coronary arteriograms, negative exercise tests, and no ST segment depression on the electrocardiogram, an increase in the rate of atrial pacing transiently decreased coronary sinus oxygen saturation but within 20 s oxygen saturation returned to the control value. In six patients with coronary artery disease ST segment depression developed during atrial pacing. The coronary sinus oxygen saturation fell and remained reduced until pacing was discontinued. The size of the fall of coronary sinus oxygen saturation increased with increasing heart rate. In seven patients with coronary artery disease the ST segments were unaltered during atrial pacing and coronary sinus oxygen saturation did not fall. Ten patients with syndrome X were studied. In six ST segment depression developed on atrial pacing. In five, three of whom developed ST segment depression, the changes in coronary sinus oxygen saturation during atrial pacing were similar to those observed in patients without any evidence of coronary artery disease. In three, all of whom developed ST segment depression, coronary sinus oxygen saturation gradually increased throughout the period of atrial pacing. In two patients coronary sinus oxygen saturation fell in a manner similar to that observed in patients with obstructive coronary artery disease who developed ST segment depression on pacing. Thus regulation of coronary blood flow in normal persons in response to an increase of heart rate is rapid. Oxygen extraction across the coronary bed can increase by up to 30% and a persistent increase in oxygen extraction is an indicator of myocardial ischaemia. The term "syndrome X" does not describe a homogeneous group of patients but in the majority coronary sinus oxygen saturation does not fall despite symptoms and changes on the electrocardiogram, indicating that inadequate coronary blood flow is not the dominant mechanism.

Exertional gastro-oesophageal reflux: a mechanism for symptoms in patients with angina pectoris and normal coronary angiograms

During 24 hour oesophageal pH monitoring 52 patients who had angina pectoris and normal coronary angiograms underwent exercise testing, as far as their symptoms allowed, on a treadmill to determine whether gastro-oesophageal reflux occurred during exertion. In 11 patients the 24 hour oesophageal pH score was abnormally high; 10 of these showed exertional gastro-oesophageal reflux, and in nine this was associated with their usual chest pain. A further 13 patients had a normal 24 hour pH score but had exertional reflux coincident with chest pain during exercise testing. The mean lower oesophageal sphincter pressure in both of these groups of patients was appreciably lower than that in 28 patients who had a normal 24 hour pH score and no exertional reflux. These findings suggest that exertional gastro-oesophageal reflux accounts for the symptoms of a large proportion of patients who have angina pectoris and normal coronary angiograms and that oesophageal pH monitoring during exercise testing on a treadmill enables this group of patients to be identified.

The oesophagus as a cause of recurrent chest pain: which patients should be investigated and which tests should be used?

Investigations of the oesophagus were undertaken in 50 consecutive patients who presented with recurrent chest pain thought to be non-cardiac in origin after cardiological assessment. An oesophageal disorder was demonstrated in 60%, gastro-oesophageal reflux and diffuse oesophageal spasm being the two commonest entities. However, routine contrast radiology and upper gastrointestinal endoscopy revealed abnormalities in only a minority of patients. Patients with non-cardiac chest pain of uncertain origin should initially undergo endoscopy. If no major abnormalities are detected radionuclide oesophageal transit studies, oesophageal manometry, and ambulatory monitoring of oesophageal pH should be carried out.

Anxiety and depression in patients with chest pain referred for exercise testing

Anxiety and depression were measured in 87 consecutive patients (65 males, 22 females) with chest pain before diagnostic exercise treadmill testing. Chest pain was assessed as typical or atypical of angina by an independent observer. Fifty exercise tests were positive; thirty-seven were negative (including nineteen submaximal). Patients with negative tests had significantly higher scores for anxiety and higher depression scores than those with positive tests. 12% of patients with positive tests were women compared with 43% with negative tests. 27 patients (73%) with negative tests had atypical pain compared with 6 (12%) with positive tests. Depressed patients walked for a significantly shorter time. The probability of a negative test in patients without anxiety or depression who had typical pain was 8% in males and 32% in females; the probability of a negative test in patients who were both anxious and depressed and had atypical pain was 97% in males and 99% in females. Diagnostic exercise testing in patients with both affective symptoms and atypical chest pain may be unhelpful, misleading, and uneconomical.