Efficiency of ergonovine echocardiography in detecting angiographically assessed coronary vasospasm

Diagnostic and Prognostic Value of Ergonovine Echocardiography for Noninvasive Diagnosis of Coronary Vasospasm

OBJECTIVES

This study sought to obtain large-scale evidence supporting the clinical usefulness of ergonovine echocardiography.

BACKGROUND

The role of noninvasive ergonovine provocation testing with echocardiographic monitoring of ventricular wall motion (ergonovine echocardiography) needs to be defined.

METHODS

Clinical data of patients who underwent ergonovine echocardiography in 3 tertiary referral hospitals in South Korea were analyzed.

RESULTS

Ergonovine echocardiography was performed in 14,012 patients (mean age 52.8 ± 11.1 years; 6,213 [44.3%] women) after exclusion of significant coronary arterial stenosis by functional (treadmill or perfusion scan, n = 9,824) or anatomic test (invasive or computerized tomographic coronary angiography, n = 4,188). Premature termination developed in 0.4% (n = 51), and a positive result was observed in 2,144 patients (15.3%), with variable frequencies according to the diagnosis (acute coronary syndrome [38.2%], variant angina [31.8%], effort angina [14.9%], aborted sudden cardiac death [17.6%], syncope [9.9%]). There was no mortality or development of myocardial infarction during the test. During median follow-up of 11.4 (interquartile range: 7.2 to 15.8) years, death of any cause and cardiovascular death occurred in 494 and 143 patients, respectively. The 10-year overall (96.7 ± 0.2% vs. 91.5 ± 0.6%; p < 0.0001) and cardiovascular mortality-free (99.2 ± 0.1% vs. 96.7 ± 0.4%; p < 0.0001) survival rates were lower in patients with positive ergonovine echocardiography. Regarding patients with positive test results, the functional test group and the anatomic test group did not show a significant difference in the survival rates. After adjustment of age and male sex, a positive test was an independent risk factor associated with all-cause mortality (hazard ratio: 1.879, 95% confidence interval: 1.548 to 2.280; p < 0.001) and cardiovascular death (hazard ratio: 2.903, 95% confidence interval: 2.061 to 4.089; p < 0.001).

CONCLUSIONS

Ergonovine echocardiography for coronary vasospasm diagnosis could be safely performed even without angiographic documentation of fixed coronary stenosis depending on the clinical presentation, and provided important prognostic implication. Ergonovine echocardiography can replace the invasive spasm provocation testing, which has been overlooked unfairly.

Thrombus and Plaque Erosion Characterized by Optical Coherence Tomography in Patients With Vasospastic Angina

INTRODUCTION AND OBJECTIVES

Vasospastic angina (VSA) can result in endothelial damage and thrombus formation. The aim of this study was to evaluate the incidence of thrombus and plaque characteristics at coronary spasm segments compared with nonspasm segments by using optical coherence tomography (OCT) in patients with suspected VSA.

METHODS

One hundred and eighty-three patients with suspected VSA were enrolled in this study. The ergonovine provocation test was performed in all patients for the diagnosis of VSA except in patients with spontaneous spasm. All target lesions were analyzed by OCT. Plaque erosion was defined as the presence of attached thrombus overlying an intact fibrous cap and visualized plaque on multiple adjacent OCT frames.

RESULTS

One hundred and nine spasm segments (93 patients) were compared with 55 nonspasm segments (39 patients). Thrombus was more frequently seen at spasm segments than at nonspasm segments (28.4% vs 7.3%; P = .026) and thrombus size was larger at spasm segments than at nonspasm segments (0.26 ± 0.50 mm² vs 0.04 ± 0.01 mm²; P = .023). Thin-cap fibroatheroma was more frequently seen at nonspasm segments than at spasm segments (16.4% vs 1.8%; P = .006). Plaque erosion was more prevalent at spasm segments than at nonspasm segments (25.7% vs 5.4%; P = .001).

CONCLUSIONS

Thrombus and plaque erosion were more common at spasm segments than at nonspasm segments assessed by OCT in patients with suspected VSA. These findings suggest the potential benefit and treatment role of antiplatelet therapy in vasospastic angina.

Normal angiogram in acute coronary syndromes: the underestimated role of alternative substrates of myocardial ischemia

The study is aimed at evaluating the real incidence of normal coronary arteries and the role of alternative substrates of myocardial ischemia in patients with acute coronary syndrome (ACS) but with no coronary artery disease (CAD) in a real world secondary care public hospital. The medical records of 941 patients undergoing coronary arteriography for ACS within 48 h of onset between January 1st 2000 and November 1st 2003 were critically reviewed. In 70 patients (7.4%, 35 males, mean age 60 +/- 17.2 years) no CAD was documented. Alternative substrates of acute myocardial ischemia included coronary artery anomalies (7 patients, 10%), coronary spasm (10 patients, 14.3%), spontaneous coronary dissection (2 patients, 2.8%), paradoxical embolism through a patent foramen ovale (4 patients, 5.7%), embolism from left atrium or calcified aortic valve (4 patients, 5.7%), imbalance between oxygen demand and supply (20 patients, 28.5%), mitral valve prolapse (11 patients, 15.7%). No alternative substrates were found in 12 patients (17.1%). Patients with no CAD are more frequently female and younger. Absence of CAD is an uncommon finding in patients undergoing coronary artery angiography for ACS.

Is there a role for provocation testing to diagnose coronary artery spasm?

Spontaneous coronary artery spasm is an important cause of morbidity both in patients with coronary artery disease and in those with variant angina. A number of pharmacological agents have been identified which can provoke coronary artery spasm in susceptible patients. The role of provocation testing in the clinical diagnosis of coronary spasm is controversial. This is reflected by variations in the clinical use of provocation testing between specialist cardiac centres. Provocation testing appears to be a sensitive method of identifying patients with variant angina and active disease but such patients can often be diagnosed clinically. The specificity is less clear. There is little evidence that altering patient therapy on the basis of a positive test modifies prognosis. There may be a role for provocation testing in rare patients with refractory disease to identify a target site for coronary stenting. A more widespread use of these tests in patients with undiagnosed chest pain syndromes would not currently be recommended.

Prognostic implication of ergonovine echocardiography in patients with near normal coronary angiogram or negative stress test for significant fixed stenosis

OBJECTIVES

The goal of this study was to assess the prognostic value of ergonovine echocardiography (Erg Echo) for diagnosis of coronary vasospasm (CVS) in patients without significant fixed coronary stenosis.

MATERIAL AND METHODS

Medical records of 650 patients who underwent Erg Echo were reviewed. Before Erg Echo, absence of significant fixed coronary stenosis was confirmed by invasive coronary angiography (CAG) in 316 patients (49%) or by noninvasive confirmation of negative treadmill or normal myocardial perfusion scan in 334 patients (51%). The cardiac events after Erg Echo were tabulated and these included cardiac death, myocardial infarction (MI), readmission due to intractable chest pain.

RESULTS

The average age was 54 +/- 10 years, with 223 women and 427 men. Erg Echo was positive in 237 patients (36%), for whom long-acting calcium channel blocker and nitrates were prescribed. During follow-up (46 +/- 23 months), cardiac events developed in 13% (30 of 237) of the positive Erg Echo group and 3% (14 of 413) of the negative Erg Echo group (P <.001). Incidence of cardiac death was higher in the positive Erg Echo group (3.4% vs 0.7%, P =.022). The 5-year survival rate (93% +/- 3% vs 99% +/- 1%, P =.013) and event-free survival rate (94% +/- 2% vs 77% +/- 6%, P <.001) were significantly lower in the positive Erg Echo group. Smoking (hazards ratio 6.3; 95% CI 1.7-23.5) and multivessel spasm (hazards ratio 37.2, 95% CI, 8.1 to 170.4) were independent factors associated with cardiac death and/or MI.

CONCLUSION

Erg Echo for noninvasive diagnosis of CVS in the differential diagnosis of chest pain provides useful prognostic information for patients without significant fixed coronary stenosis and can play a role as a cost-effective diagnostic strategy in these selected patients.

Safety of ergot stress echocardiography for non-invasive detection of coronary vasospasm

BACKGROUND

The safety of ergonovine/ergometrine stress testing for coronary vasospasm when performed outside the cardiac catheterization laboratory (cath lab) has been questioned vigorously.

AIM

To assess the tolerability and safety of ergonovine/ergometrine stress testing performed in the echocardiographic laboratory (echo lab).

METHODS

We retrospectively reviewed the data prospectively collected in the echo lab of the Institute of Clinical Physiology from 1 January 1985 to 1 June 2000, from 587 tests performed on 573 patients (either ergonovine or ergometrine stress echocardiography testing). By selection, all patients had a history of chest pain, consistent with vasospastic angina, negative exercise stress testing or stress echocardiography (with dipyridamole, dobutamine or exercise), and normal or near normal resting left ventricular function. Ergonovine or ergometrine maleate was injected up to a total cumulative dosage of 0.35 mg, under continuous 12-lead electrocardiographic and two-dimensional echocardiographic monitoring.

RESULTS

There were no deaths, myocardial infarctions, ventricular fibrillations or third degree AV blocks. One patient had non-sustained ventricular tachycardia associated with transient ST segment elevation 30 min after the test. Three patients had second degree AV block associated with a positive echocardiography test that was promptly reversed by nitrates administration. Transient regional myocardial dysfunction occurred in 79 patients (13%). Limiting ischaemia-independent side effects were present in 17 patients (3%): hypotension in one, arterial hypertension in five, non-sustained ventricular tachycardia in two and nausea or vomiting in ten. The test was well tolerated and echocardiograms were interpretable in 97% of the tests performed.

CONCLUSION

Pharmacological stress echocardiography with either ergonovine or ergometrine is well tolerated and can be performed with relatively low risk in the echo lab in properly selected patients in whom coronary vasospasm is suspected.