Major complications during spasm provocation tests with an intracoronary injection of acetylcholine

Do changes in intracoronary pressure aid coronary spasm diagnosis using the spasm provocation test?

BACKGROUND

Although the spasm provocation test (SPT) can diagnose coronary spasms, it would be helpful if it could also predict their occurrence.

AIM

To investigate whether coronary spasms can be predicted using changes in intracoronary artery pressure measured using a pressure wire during the SPT.

METHODS

Seventy patients underwent SPTs with pressure-wire measurement of intracoronary artery pressure. During each SPT, the pressure wire was advanced into the distal portion of the right coronary artery (RCA) and left anterior descending coronary artery, and the ratio of intracoronary pressure to aortic pressure (Pd/Pa) was monitored. Coronary spasm was defined as an arterial narrowing of > 90% in response to the administration of acetylcholine (ACh), with chest symptoms and/or ischemic electrocardiographic changes. ACh was administered to the RCA at low, moderate, or high doses of 20, 50, or 80 µg, respectively, and to the left coronary artery (LCA) at low, moderate, or high doses of 50, 100, or 200 µg, respectively. Coronary arteries with coronary spasms at low doses of ACh were defined as group L, and those with coronary spasms at moderate or high doses were defined as group MH. Those who did not occur coronary spasms at any ACh dose were designated as group N.

RESULTS

Among the 132 coronary arteries assessed using a pressure wire, there were 49 in group N, 25 in group L, and 58 in group MH. Baseline Pd/Pa was the lowest in group L (P = 0.001). The decrease in the Pd/Pa between baseline to low doses of ACh was lower in group MH than in group N (P < 0.001). A receiver-operating characteristics analysis showed that the cutoff baseline Pd/Pa value for predicting group L was 0.95, with a sensitivity of 0.600 (15/25) and a specificity of 0.713 (76/107) and that the cutoff value of Pd/Pa from baseline to low doses of ACh for predicting group MH was -0.04, with a sensitivity of 0.741 (43/58) and a specificity of 0.694 (34/49).

CONCLUSION

These findings suggest that indices of intracoronary pressure during SPT may be useful means for predicting the occurrence of coronary spasms.

Angina And Arrhythmia Symptoms Following Multiple Bee Stings: Kounis Syndrome

Kounis syndrome (KS) is an acute coronary syndrome including coronary spasm, acute myocardial infarction, and stent thrombosis preceded by an anaphylactic, anaphylactoid, allergic, or hypersensitivity injury. In this case presentation, we discussed Type I and Type II KS. Case 1 was a 72-y-old man who presented to the emergency department with allergic symptoms and chest pain that developed after multiple bee stings. Electrocardiography showed ST depression in the lateral leads. Case 2 was a 42-y-old woman who presented to the emergency department with complaints of chest pain, dizziness, and presyncope that developed after multiple bee stings. Mobitz Type II Block with right bundle branch block was observed in 42 beats·min^-1 in the electrocardiography. Both patients were first treated for allergic reaction. Although early percutaneous coronary intervention was performed for graft thrombosis in Case 1, a permanent pacemaker was inserted in Case 2. The patients were discharged without any complications. Increasing physician awareness towards the existence of KS can prevent fatal outcomes with early diagnosis and treatment.

A Practical Approach to Invasive Testing in Ischemia with No Obstructive Coronary Arteries (INOCA)

Up to 65% of women and approximately 30% of men have ischemia with no obstructive coronary artery disease (CAD; commonly known as INOCA) on invasive coronary angiography performed for stable angina. INOCA can be due to coronary microvascular dysfunction or coronary vasospasm. Despite the absence of obstructive CAD, those with INOCA have an increased risk of all-cause mortality and adverse outcomes, including recurrent angina and cardiovascular events. These patients often undergo repeat testing, including cardiac catheterization, resulting in lifetime healthcare costs that rival those for obstructive CAD. Patients with INOCA often remain undiagnosed and untreated. This review discusses the symptoms and prognosis of INOCA, offers a systematic approach to the diagnostic evaluation of these patients, and summarizes therapeutic management, including tailored therapy according to underlying pathophysiological mechanisms.

Acetylcholine Use in Modern Cardiac Catheterization Laboratories: A Systematic Review

BACKGROUND

The use of acetylcholine for the diagnosis of vasospastic angina is recommended by international guidelines. However, its intracoronary use is still off-label due to the absence of safety studies. We aimed to perform a systematic review of the literature to identify adverse events related to the intracoronary administration of acetylcholine for vasoreactivity testing to fill this gap.

METHODS AND RESULTS

We conducted a systematic review of observational studies and randomized controlled trials dealing with the intracoronary administration of acetylcholine. Articles were searched in MEDLINE (PubMed) using the MeSH strategy. Three independent reviewers determined whether the studies met the inclusion and exclusion criteria. A total of 434 articles were selected. Data concerning clinical characteristics, study population, acetylcholine dosage, and adverse effects were retrieved from the articles. Overall, 71,566 patients were included, of which only 382 (0.5%) developed one adverse event, and there were no fatal events reported (0%).

CONCLUSIONS

Intracoronary administration of acetylcholine in the setting of coronary spasm provocation testing is safe and plays a central role in the evaluation of coronary vasomotion disorders, making it worthy of becoming a part of clinical practice in all cardiac catheterization laboratories.

[Methergin pour le diagnostic de l'angor spastique : voie intraveineuse ou intracoronaire ?]

BACKGROUND

Vasospastic angina is an infrequent underlying cause of angina and is under-diagnosed. Ergonovine provocation tests can be performed via intravenous or intracoronary injections. Although the safety profile of intracoronary injection has been well documented, no study has yet compared the intracoronary and intravenous injections regarding the positivity rate of the test.

AIMS

This study sought to compare the positivity rate of intravenous versus intracoronary injection of ergonovine in the diagnosis of vasospastic angina.

METHODS

Between January 2010 and February 2018, 427 patients with suspected vasospastic angina underwent an ergonovine provocation test in 2 tertiary hospitals in France and were retrospectively included in this study. Injection was performed via the intravenous or the intracoronary route. The primary endpoint was the positivity rate of the test. Propensity score matching was used to account for confounding factors.

RESULTS

427 patients were included in the study. Mean age was 60.3 (+/- 12.4) years. There were 247 (58%) females and 97 (23%) smokers. The intracoronary route was used in 199 (47%) patients. The indication for the test was acute coronary syndrome for 121 (28%). No rhythmic complications or deaths were reported. After propensity-matching, the baseline characteristics of the 2 groups (148 patients in each) were comparable. The positivity rate was 24% in the intracoronary group and 9% in the intravenous group (OR [95%CI]: 3.2 [1.6, 6.4]).

CONCLUSIONS

Intracoronary injection of ergonovine is safe and associated with a positivity rate of the test three times higher compared to intravenous injection.

Intracoronary acetylcholine testing among 746 consecutive Japanese patients with angina-like chest pain and unobstructed coronary artery disease

Aims 

Intracoronary acetylcholine (ACh) testing is useful for the detection of epicardial spasm (ES) and coronary microvascular spasm (CMS). We retrospectively analysed the incidence of ES and CMS in consecutive Japanese patients with unobstructed coronary artery disease.

Methods and results

From January 1991 to February 2019, we performed intracoronary ACh testing of 1864 patients. Among these patients, a total of 746 consecutive patients (254 women, mean age 64 ± 11 years) who underwent first diagnostic angiography for suspected myocardial ischaemia and had unobstructed coronary arteries (<50%) were enrolled. Epicardial spasm was defined as ≥90% stenosis and usual chest symptoms and ischaemic ECG changes, while CMS was defined as <75% stenosis and usual chest symptoms and ischaemic ECG changes. We performed intracoronary ACh testing on both coronary arteries in 96% (716/746) of all subjects. Overall, ES was found in 329 patients (44%), whereas CMS was revealed in 40 patients (5%) including 4 patients with coexisting ES. In patients with ES, women made up 22%, and approximately three-quarters of the patients had resting chest pain. In contrast, women composed 65% (26/40) of those with CMS, and 15 patients with CMS had another chest symptom. Coronary microvascular spasm was frequently observed in the left coronary artery (LCA) but not the right coronary artery. Electrical cardioversion was necessary for two patients.

Conclusions 

Coronary microvascular spasm was recognized in only 5% of consecutive Japanese patients with unobstructed coronary artery disease, whereas ES was revealed in 44% of those patients. Coronary microvascular spasm was often observed in women and in the LCA.

Coincidence between spontaneous and inducible coronary spasm: acetylcholine test is clinically valued for diagnosing coronary spasm

There is no report regarding the correlation between spontaneous documented coronary spasm and acetylcholine (ACh)-inducible spasm. We retrospectively analyzed the coincidence between angiographical spontaneous coronary spasm and ACh-inducible spasm in the same patients. We recruited 28 patients with 30 angiographical spontaneous coronary spasm in 6009 patients with diagnostic and follow-up coronary arteriography from Jan 1991 and Mar 2019 in the cardiac catheterization laboratory. We could perform intracoronary ACh testing in 19 patients with 20 vessels. ACh was injected in incremental dose of 20/50/100 μg into the left coronary artery and 20/50/80 μg into the right coronary artery. Positive spasm was defined as > 90% stenosis and ischemic ECG changes. Angiographical documented spontaneous coronary spasm was observed in 0.47% (28/6009) of patients with diagnostic and follow-up coronary angiography. Intracoronary administration of ACh reproduced 15 spontaneous coronary spasm and no provoked spasm was observed in the remaining 5 vessels due to the administration of nitroglycerine or under medications. Spasm-provoked sites by ACh tests and ACh-inducible spasm configurations were almost similar to spontaneous spasm. Coincidence of provoked spasm site (93.3% vs. 6.7%, p < 0.001) and spasm configuration (93.3% vs. 6.7%, p < 0.001) was markedly higher than discordance. Intracoronary ACh testing can reproduce spontaneous coronary artery spasm in 75% of vessels with almost similar sites and same morphological characteristics irrespective of the administration of nitroglycerine or vasodilators. ACh test is a reliable method to document coronary artery spasm in the clinic.

Bronchial Asthma and Rest Angina: Is It Safe to Perform Acetylcholine Spasm Provocation Tests in These Patients?

Objective Acetylcholine (ACh) use in patients with bronchial asthma (BA) is contraindicated. We examined the clinical usefulness and safety of ACh spasm provocation tests in rest angina patients with BA. Patients The study subjects were 495 rest angina patients (mean age: 64.4±10.9 years old, male: 81.0%). Organic stenosis was found in 69 patients (13.9%). Methods We investigated 495 rest angina patients who underwent ACh spasm provocation tests. ACh was injected in incremental doses of 20/50/100/200 μg into the left coronary artery and 20/50/80 μg into the right coronary artery. Provoked positive spasm was defined as transient ≥90% luminal narrowing and usual chest pain or ischemic electrocardiogram changes. Results Among 495 rest angina patients, 13 (2.6%) were complicated with BA. Eleven patients with BA were controlled under medications, and two patients had a history of medication for BA. The clinical characteristics were not markedly different between rest angina patients with and without BA. The rate of multi-vessel spasm was markedly higher in patients with BA than that in those without BA. No complications during ACh spasm provocation tests were recognized in rest angina patients with BA, whereas major complications in those without BA were observed in eight patients including two ventricular fibrillations, three non-sustained ventricular tachycardias, and three shocks. We were able to perform all 495 ACh spasm provocation tests without any irreversible complications, while electrical defibrillation was necessary for 2 patients without BA. Conclusion We were able to perform ACh spasm provocation tests in rest angina patients with BA irrespective of the off-label use of ACh.

Role of acetylcholine spasm provocation test as a pathophysiological assessment in nonobstructive coronary artery disease

Coronary angiography (CAG) sometimes shows nonobstructive coronary arteries in patients with suspected angina or acute coronary syndrome (ACS). The high prevalence of nonobstructive coronary artery disease (CAD) in those patients has recently been reported not only in Japan but also in Western countries, and is clinically attracting attention. Coronary spasm is considered to be one of the leading causes of both suspected stable angina and ACS with nonobstructive coronary arteries. Coronary spasm could also be associated with left ventricular dysfunction leading to heart failure, which could be improved following the administration of calcium channel blockers. Because we rarely capture spontaneous attacks of coronary spasm with electrocardiograms or Holter recordings, an invasive diagnostic modality, acetylcholine (ACh) provocation test, can be useful in detecting coronary spasm during CAG. Furthermore, we can use the ACh-provocation test to identify high-risk patients with coronary spasm complicated with organic coronary stenosis, and then treat with intensive care. Nonobstructive CAD includes not only epicardial coronary spasm but also microvascular spasm or dysfunction that can be associated with recurrent anginal attacks and poor quality of life. ACh-provocation test could also be helpful for the assessment of microvascular spasm or dysfunction. We hope that cardiologists will increasingly perform ACh-provocation test to assess the pathophysiology of nonobstructive CAD.

ST segment elevation in an adult chest pain patient: A case of coronary artery vasospasm

Chest pain is one of the most common symptoms of patients presenting to the emergency department (ED) in the United States, accounting for up to eight million cases annually. We present a 55-year-old male who was brought in to the ED with sudden onset chest pain and was found to have ST-segment elevations in the infero-lateral leads on electrocardiogram (ECG). These changes resolved with nitroglycerin. Coronary artery vasospasm was diagnosed as coronary angiogram was normal. Calcium channel blocker was prescribed with good symptom relief. The most important teaching point is, coronary vasospasm as a cause of ST-segment elevation is missed frequently and should be considered among the differentials in patients presenting with chest pain. Nitrates and/or calcium channel blockers along with avoidance of triggers can help in symptom management.

Pharmacological spasm provocation testing in 2500 patients: provoked spasm incidence, complications and cardiac events

Pharmacological spasm provocation tests such as acetylcholine (ACh) and ergonovine (ER) had been performed in the clinic. We retrospectively analyzed the incidence of provoked spasm, complications during testing and the cardiac events after these tests. From January 1991 and October 2018, we performed pharmacological spasm provocation tests in 2500 patients: 1810 ACh tests, 1232 ER tests, 542 both tests, and 310 ACh added after ER tests. ACh was injected in incremental doses of 20/50/100/200 μg into the LCA and 20/50/80 μg into the RCA. ER was administered as a total dose of 64 μg into the LCA and 40 μg into the RCA. When adding ACh after ER, the total dose was 50/80 μg into the RCA and 100/200 μg into the LCA. Positive spasm was defined as ≥ 90% stenosis and usual chest pain or ischemic ECG changes. Mean follow-up duration was 47.5 ± 29.9 months. Overall, provoked positive spasm was found in 1095 patients (43.8%). The incidence of positive provoked spasm during ACh testing was significantly higher than that during other tests (ACh: 48.7% vs. ER: 28.9%, Both: 24%, ACh added after ER: 33.5%, p < 0.001). Multiple spasms were remarkably more frequent during ACh testing compared with the other 3 types of testing (ACh: 28.2% vs. ER: 7.4%, Both: 4.1%, ACh added after ER: 13.2%, p < 0.001). No death or acute myocardial infarction was observed, while major complications during ACh testing were significantly more frequent than during ER testing. Readmission due to recurrent angina pectoris in spasm-positive patients was remarkably more frequent than in spasm-negative patients. The incidence of sudden cardiac death, ventricular fibrillation, and acute coronary syndrome were not different between the spasm-positive and spasm-negative groups during the follow-up periods. We could perform all spasm provocation tests without any irreversible complications. All sequential spasm provocation tests were useful for documenting coronary spasm.

Myocardial Ischemic Syndromes, Heart Failure Syndromes, Electrocardiographic Abnormalities, Arrhythmic Syndromes and Angiographic Diagnosis of Coronary Artery Spasm: Literature Review

In coronary artery spasm (CAS), an excess coronary vasoconstriction causing total or subtotal vessel occlusion could lead to syncope, heart failure syndromes, arrhythmic syndromes, and myocardial ischemic syndromes including asymptomatic myocardial ischemia, stable and unstable angina, acute myocardial infarction, and sudden cardiac death. Although the clinical significance of CAS has been underrated because of the frequent absence of symptoms, affected patients appear to be at higher risk of syncope, serious arrhythmias, and sudden death than those with classic Heberden's angina pectoris. Therefore, a prompt diagnosis has important therapeutic implications, and is needed to avoid CAS-related complications. While a definitive diagnosis is based mainly on coronary angiography and provocative testing, clinical features may help guide decision-making. We perform a literature review to assess the past and current state of knowledge regarding the clinical features, electrocardiographic abnormalities and angiographic diagnosis of CAS, while a discussion of mechanisms is beyond the scope of this review.

Clinical characteristics in patients with rest angina and hypoplastic right coronary artery

Hypoplastic coronary artery disease is a rare congenital abnormality reported to be associated with myocardial infarction and sudden cardiac death. Provoked positive spasm in the left circumflex coronary artery (LCX) with pharmacological spasm provocation tests was remarkably lower than other coronary arteries. We sometimes encountered patients with rest angina and hypoplastic right coronary artery (H-RCA). Among 5953 patients with diagnostic and follow-up coronary arteriography, we found 93 patients (1.6%) with H-RCA. During the same period, we could perform spasm provocation tests in 564 patients with rest angina including 13 patients with H-RCA and 249 patients with effort angina including 10 patients with H-RCA. Pharmacological spasm provocation tests were performed in 51 of 93 patients including 34 patients with ischemic heart disease (IHD) and 17 patients with non-IHD. Provoked spasm incidence in patients with IHD was higher than in those with non-IHD but not significant (52.9% vs. 29.4%, p = 0.1114). Provoked positive spasm in the LCX in patients with rest angina and H-RCA was significantly higher than that in those without H-RCA (69.2% vs. 23.4%, p < 0.001). Provoked spasm on both left anterior descending artery and LCX in patients with rest angina and H-RCA was also remarkably higher than in those without H-RCA (53.8% vs. 3.1%, p < 0,001). There were no clinical differences between patients with and without H-RCA rest angina. Two-vessel spasm (61.5% vs. 0%, p < 0.01) and LCX-provoked spasm (69.2% vs. o%, p < 0.01) were significantly higher in patients with H-RCA and rest angina than that in those with H-RCA and effort angina. In patients with rest angina and H-RCA, LCX-positive spasm was significantly higher and these patients may have a potential of high disease activity in the clinic as a coronary spastic angina.

[Vasospastic angina: An under-diagnosed pathology]

The clinical and physiopathological clinical entity known as spastic angina or variant angina has been long documented. It remains, however, an under-estimated condition, which is insufficiently diagnosed and explored. This pathology is associated with severe complications such as heart rhythm disorders, which may potentially result in ventricular fibrillation and cause sudden death. In Japan, this condition occurs more frequently and is better documented. Stimulation tests are also carried out more often and have a higher positivity rate than in France where vasospastic angina is less frequently reported and where provocation tests are associated with negative results and are, consequently, performed less often. In order to improve the detection of this pathology, its potential presence should be explored in patients with rest angina who experience chest pain in the second half of the night and also in instances of acute coronary syndrome with sudden death and no angiographically visible coronary artery disease. The diagnosis should be confirmed by means of ergonovine provocation tests. In order to enhance the sensitivity of these tests without increasing the risk of complications, injection of ergonovine should be preferably carried out via the intracoronary route. By increasing the frequency and sensitivity of these tests, this pathology, which responds well to medical treatment in many cases, could be amenable to therapeutic management as any other form of coronary artery disease.

Hemodynamic and autonomic effects of low-dose glyceryl trinitrate used to test endothelium-independent vasodilation of the brachial artery

Smooth muscle function is explored by sublingual glyceryl trinitrate (GTN) administration to compare with endothelium-dependent vasodilation of the brachial artery by flow-mediated-dilation (FMD). This study compared the hemodynamic and autonomic effects of the two most often used GTN dosages. In 80 essential hypertensive patients (HT) and 60 normotensive subjects (NT), FMD of the brachial artery and endothelium-independent response to sublingual GTN (25 μg and 400 μg) were evaluated by high-resolution ultrasound and automated image analysis. In 10 HT, muscle sympathetic nerve activity (MSNA) was also assessed by microneurography. HT showed significantly (p < .01) lower FMD (5.5 ± 3.3%) compared to NT (6.9 ± 2.2%). The response to GTN 25 μg tended to be lower (HT:7.2 ± 3.3%; NT:7.9 ± 2.9%; p = .06), whereas response to GTN 400 μg was similar (HT:14.3 ± 4.8%, NT:14.5 ± 4.7%, p = ns). Blood pressure (BP) reduction induced by GTN 400 μg (systolic-BP:-3.2 ± 7.7 mm Hg, diastolic-BP:-4.7 ± 5.0 mm Hg) was greater (p < .001) compared to GTN 25 μg (systolic-BP:-0.7 ± 5.8 mm Hg, diastolic-BP:-0.7 ± 4.4 mm Hg). Changes in heart rate were also greater (+5.6 ± 6.4 bpm versus -0.2 ± 5.4 bpm, p < .001). This behaviour was similar in either NT or HT. MSNA was significantly increased by GTN 400 μg (31 ± 7bursts/min to 41 ± 6bursts/min, p < .001) but not by 25 μg (33 ± 9bursts/min to 37 ± 11bursts/min, p = .19). In conclusion, the administration of low-dose GTN allows exploring endothelium-independent vasodilation in FMD protocols, inducing only modest hemodynamic and sympathetic responses.

Acetylcholine spasm provocation test by trans-radial artery and brachial vein approach

BACKGROUND

Temporary pace maker is necessary because of transient block or bradycardia during the intracoronary acetylcholine spasm provocation tests based on the Japanese Circulation Society guidelines.

OBJECTIVES

We examined the feasibility and safety of the acetylcholine spasm provocation test via the radial artery and brachial vein approach.

METHODS

We tried to perform the acetylcholine spasm provocation tests in 252 patients via the radial artery and brachial vein approach procedures during 5 years. Acetylcholine was injected in incremental doses of 20/50/80 μg into the right coronary artery (RCA) and 20/50/100/200 μg into the left coronary artery (LCA). Back-up pacing rate was set at 40 beats/min. Positive spasm was defined as transient ≥90% luminal narrowing and ischemic electrocardiographic change or usual chest pain.

RESULTS

The procedure success of radial artery and brachial vein access was 94.4% (238/252) and 93.3% (235/252), respectively. We performed 221 patients (87.7%) with acetylcholine tests by radial artery and brachial vein approach. We changed to the brachial approach due to the failures of radial artery access in 14 patients. We also changed to the femoral vein in 11 patients and internal jugular vein in two patients. Back-up pace maker rhythm was observed in 92.1% (232/252) of all study patients, while it was significantly higher in the RCA testing than that in the LCA tests (84.9% (191/225) vs. 52.2% (131/251), P < 0.001). No irreversible complication was found.

CONCLUSIONS

We recommend the radial artery and brachial vein approach for safety and convenience when performing the acetylcholine spasm provocation tests.

Catheter-induced Spasm in the Proximal Right Coronary Artery

Objectives The clinical characteristics in patients with catheter-induced spasm in the proximal right coronary artery (RCA) are controversial. We performed a clinical analysis of catheter-induced spasm in the RCA. Methods We retrospectively analyzed 5,296 consecutive patients who underwent diagnostic or follow-up angiography during a 26-year period. During this period, we found 40 patients with catheter-induced spasm in the RCA. We compared the clinical characteristics and procedures of cardiac catheterization in patients with catheter-induced spasm in the RCA with those in patients without such spasm. Results The frequency of catheter-induced spasm in the RCA was 0.75% (40/5,296). We performed pharmacological spasm provocation tests in 36 of 40 patients after spasm relief. Positive spasm was observed in 32 patients (88.9%), and 25 patients (78.1%) had multiple spasms. The catheter procedures, including the approach sites (radial/brachial/femoral), catheter size (4/5/6Fr) and catheter type (Judkins right/Sones/Shared/Judkins left 3.5/Amplatz) were not markedly different between the two groups. A multivariate analysis showed that positive spasm [odds ratio (OR): 7.030, 95% confidence interval (CI): 1.920-25.700], a younger age (OR: 0.937, 95% CI: 0.910-0.965) and diabetes mellitus (OR: 0.278, 95% CI: 0.083-0.928) were the determinant factors for the catheter-induced spasm. Conclusion Approximately 80% of patients with catheter-induced spasm in the proximal RCA had coronary spastic angina. Positive provoked spasm was the most powerful determinant factor for catheter-induced spasm.

Differential incidence and morphology of provoked spasm between intracoronary acetylcholine and ergonovine testing: recommendation of supplementary use

When cardiologists diagnose patients with coronary spastic angina, Japanese Circulation Society (JCS) guidelines recommend the intracoronary injection of acetylcholine (ACh) and ergonovine (ER) as class I. However, the pharmacological difference between ACh and ER is controversial in the clinic. We performed both ACh and ER tests in the same 528 patients during 26 years. We investigated the provoked spasm configuration, spasm site, and clinical characteristics of provoked spasm between ACh and ER, retrospectively. We defined positive spasm as ≥90% luminal narrowing. Provoked positive spasm was observed in 161 right coronary arteries (RCA) including 83 ACh just positive, 35 ER just positive, and 43 both positive. In contrast, positive spasm was documented in 172 left coronary arteries (LCA) including 94 ACh just positive, 28 ER just positive, and 50 both positive. ACh provoked spasm more distally and diffusely, while ER induced spasm more proximally and totally or focally in the RCA. In the LCA, ACh provoked spasm more proximally, whereas ER induced spasm more distally. ER testing after the negative ACh tests of RCA and LCA documented new positive spasms in 10.3% (35/340) and 7.4% (28/376), respectively. Coronary artery trees may each have a sensitive receptor on each segment. We recommend the supplementary use of ACh and ER to document coronary artery spasm in the cardiac catheterization laboratory.

[Coronary spasm a diagnostic and therapeutic challenge]

Vasospastic angina is a clinical and physio-pathological entity, which has been documented for many years, but its diagnosis is under-estimated despite the fact that though inadequately considered and investigated. This condition is potentially serious and can sometimes trigger severe arrhythmia resulting in ventricular fibrillation and sudden death. This pathology has a higher incidence in Asia, where it is, therefore, better documented with provocative testing being carried out more frequently, while in France, these tests are not sufficiently performed probably due to the fact that they often produce negative findings. Provocative tests with Ergonovine injection should be performed via intra-coronary to improve its sensibility. Should this test become more sensitive and more routinely performed, this condition, which often responds well to medical treatment, could regain appropriate recognition as a coronary disease.

Impact of pharmacological spasm provocation test in patients with a history of syncope

Coronary artery spasm is involved in the pathogenesis of various cardiac disorders. We investigated patients with a history of syncope who underwent elective coronary angiography. We retrospectively analyzed 5781 consecutive patients who had diagnostic or follow-up angiography during a 26-year period. During this period, we found 95 patients with a history of syncope before elective coronary angiography. Pharmacological spasm provocation testing was performed in 64 patients with a history of syncope (<1 year). Positive pharmacological response was observed in 48 patients, while the remaining 16 patients had negative tests. Positive spasm was defined as a transient ≥90% narrowing with ischemic electrocardiographic changes. Among the 64 patients, definite coronary spastic angina (CSA) was found in 35 patients (54.7%) and suspected CSA was found in 13 patients (20.3%). Among the 35 patients with definite CSA, 22 patients (62.9%) had chest symptoms before syncope, but 13 (37.1%) had no chest symptom before syncope. No difference in clinical characteristics was observed between the two groups. Focal spasm during pharmacological spasm provocation tests was significantly higher in patients with chest symptoms than in those without chest symptoms before syncope (54.3 vs. 12.0%, p < 0.002). CSA was observed in 75.0% of patients with a history of syncope (<1 year). Thirteen patients with definite CSA had neither chest pain nor chest pressure before syncope. We should therefore investigate coronary artery spasm as a potential etiology in patients with a history of syncope.

The acetylcholine administration time plays the key role for provoked spasm in the spasm provocation test

BACKGROUND

Acetylcholine (ACh) was administered for 3min in the ENCORE study, while the Japanese Circulation Society guidelines recommended the 20s ACh injection as an ACh test.

OBJECTIVES

We compared the ischemic findings between ACh administration for 3min and ACh injection for 20s in the same patients and in the same ACh doses without administration of nitrates in the left coronary artery.

METHODS

We investigated 30 patients with ischemic heart disease (25 men, 67±10 years, ACh 50μg: 3, ACh 100μg: 9, ACh 200μg: 18) by the above two ACh injection procedures. Temporary pacemaker was inserted and set at the rate of 40/min. Positive provoked spasm was defined as transient ≥90% narrowing and typical chest symptoms or ischemic electrocardiographic (ECG) changes.

RESULTS

Provoked spasm was observed in 22 patients with ACh 20s injection, while 10 patients had provoked spasm by ACh 3min administration (73.3% vs. 33.3%, p<0.05). Ischemic ECG changes (50.0% vs. 23.3%, p<0.05) and chest symptoms (73.3% vs. 43.3%, p<0.05) were significantly higher with ACh 20s injection than ACh 3min administration. Pacemaker rhythm was recognized in 19 patients with ACh 20s injection, whereas 7 patients with ACh 3min administration had a pacemaker rhythm (63.3% vs. 23.3%, p<0.01). Maximal ST elevation by ACh 20s injection was significantly higher than that by ACh 3min administration (0.47±0.94 vs. 0.13±0.51, p<0.05), while maximal ST depression was not different between the two procedures. Coronary artery diameter after ACh 20s injection was significantly lower than that after ACh 3min administration in the left anterior descending artery.

CONCLUSIONS

ACh administration procedures (3min or 20s injection) may influence the ischemic findings in spasm provocation testing.

Overview of the pharmacological spasm provocation test: Comparisons between acetylcholine and ergonovine

The spasm provocation tests of ergonovine and acetylcholine have been employed in the cardiac catheterization laboratory. Ergonovine acts through the serotogenic receptors, while acetylcholine acts through the muscarinic cholinergic receptors. Different mediators may have the potential to cause different coronary responses. However, there are few reports concerning the coronary response between ergonovine and acetylcholine in the same patients. Acetylcholine is supersensitive for females; spasm provoked by ergonovine is focal and proximal, whereas provoked spasm by acetylcholine is diffuse and distal. We should use both tests as supplementary in the clinic because ergonovine and acetylcholine have self-limitations to induce coronary spasms during daily life. The maximal pharmacological doses, administration methods, and the angiographical positive definition are remarkably different for each institution in the world. We recommend the pharmacological spasm provocation tests as Class I in the guidelines in patients with vasospastic angina throughout the world.

Differential incidence and type of spasm according to coronary arterial location

BACKGROUND

We encounter a less provoked spasm in the left circumflex artery (LCX) by acetylcholine (ACh) testing compared with left anterior descending artery and right coronary artery (RCA) in the real world.

OBJECTIVES

We investigated the clinical characteristics of provoked spasm in the LCX by ACh testing.

METHODS

We retrospectively analyzed consecutive 1392 ACh testing over 20 years (1991-2011). The maximal ACh dose was 100 μg into the left coronary artery and 80 μg into the RCA. Positive spasm was defined as transient of more than or equal to 90% narrowing and usual chest symptoms or ischemic ECG changes.

RESULTS

Positive provoked spasm was recognized in 622 patients (44.7%) including 456 RCA spasms, 448 left anterior descending artery spasms, and 176 LCX spasms. LCX-provoked spasm was significantly lower than other vessels (P<0.001). LCX-provoked spasm was observed in 176 patients, of whom 113 patients (64.2%) had triple-vessel spasm, 46 patients (26.1%) had double-vessel spasm, and 17 patients (9.7%) had single-vessel spasm. More than 90% patients with LCX-provoked spasm had multiple spasms. Of 17 patients with LCX single-vessel spasm, 15 patients (88.2%) had focal spasm.

CONCLUSION

Under a maximal ACh dose of 100 μg into the left coronary artery, LCX-provoked spasm was significantly lower than other vessels and more than 90% of patients had multiple spasms.

Overview of the Acetylcholine Spasm Provocation Test

The acetylcholine (ACh) spasm provocation test proposed by Yasue, Okumura et al more than a quarter-century ago has become a popular method for induction of coronary spasm. This test is safe and has a low rate of complications. However, it may be limited in its ability to document attacks in daily life because previously it was the gold-standard method for diagnosing active variant angina. There may be some clinical issues to modify for the next generation of cardiologists. A maximal ACh dose of 50/100 µg in the right coronary artery/left coronary artery is recommended in the Japanese Circulation Society guidelines. We often experienced the usefulness of a maximal ACh dose of 80/200 µg for the induction of coronary spasm in some cases with low or moderate disease activity. It may be necessary to reconsider the maximal ACh dose as a modified method for today's real-world clinical practice. In young patients with rest angina, intracoronary injection of ACh is less sensitive for diagnosis; in these cases, we recommend performing sequential spasm provocation tests. Especially in female patients, to document coronary artery spasm we recommend performing ACh tests first, instead of ergonovine tests, due to the supersensitivity of ACh. We also recommend supplementary use of ACh and ergonovine. This review summarizes our experiences with the ACh spasm provocation test over a period of 24 years. We have found it to be a reliable and useful method for contributing a variety of clinical information and recommend it to the next generation of cardiologists.

Serious cardiac complications in coronary spasm provocation tests using acetylcholine or ergonovine: analysis of 21 512 patients from the diagnosis procedure combination database in Japan

BACKGROUND

Previous studies on complications with coronary spasm provocation tests were based on small sample sizes or were limited to high-volume centers. The risk of provocation tests using acetylcholine (ACH) or ergonovine (ER) remains to be fully examined by a large-scale multicenter study.

HYPOTHESIS

ACH provocation tests are associated with a higher rate of serious cardiac complications than ER tests.

METHODS

Using the Diagnosis Procedure Combination database in Japan, we identified patients aged ≥20 years who underwent a pharmacological provocation test during coronary angiography. We assessed the composite outcome of cardiac complications requiring urgent procedures (defibrillation, chest compression, intra-aortic balloon pumping, or extracorporeal membrane oxygenation) or death on the day of the provocation test, and compared the outcome between ACH and ER tests.

RESULTS

Of 21 512 eligible patients in 602 hospitals, 10 628 (49.4%) underwent an ACH test and 10 884 (50.6%) underwent an ER test. The composite outcome occurred in 141 (0.7%) patients. The ACH group was significantly more likely to have the composite outcome than the ER group (0.9% vs 0.4%, P < 0.001). The propensity-score analyses showed consistent results (propensity score-matched, 0.9% vs 0.4%, P = 0.003; inverse probability-weighted, 0.8% vs 0.4%, P < 0.001). In a multivariable logistic regression analysis, ACH tests were significantly associated with a higher rate of the composite outcome than ER tests (odds ratio: 1.75, 95% confidence interval: 1.13-2.69, P = 0.011).

CONCLUSIONS

This retrospective cohort study suggested that ACH tests were associated with a higher rate of cardiac complications than ER tests.

Stable angina pectoris

The stable coronary artery disease (SCAD) population is a heterogeneous group of patients both for clinical presentations and for different underlying mechanisms. The recent European Society of Cardiology guidelines extensively review SCAD from its definition to patients' diagnostic and therapeutic management. In this review, we deal with five topics that, in our opinion, represent the most intriguing, novel and/or clinically relevant aspects of this complex coronary condition. Firstly, we deal with a peculiar SCAD population: patients with angina and 'normal' coronary arteries. Secondly, we reinforce the clinical importance of a diagnostic approach based on the pretest probability of disease. Thirdly, we review and critically discuss the novel pharmacological therapies for SCAD patients. Finally, we analyse the results of the most recent clinical trials comparing revascularization versus optimal medical therapy in SCAD patients and review the currently recommended use of intracoronary functional evaluation of stenosis.

One of six patients with non-ischemic heart disease exhibit provoked coronary spasms: non-ischemic heart disease associated with ischemia?

OBJECTIVE

The majority of cardiologists do not perform spasm provocation tests in patients with non-ischemic heart disease (non-IHD) or non-obstructive coronary artery disease (non-ob-CAD). We herein examined the frequency of provoked spasms in non-IHD and non-ob-CAD patients, including those with atypical chest pain (Aty), valvular heart disease (Val), hypertrophic cardiomyopathy (HCM), congestive heart failure (CHF), and others (Oth).

METHODS & RESULTS

We performed acetylcholine (ACh) spasm provocation tests over a period of 22 years (1991-2012) among 1,440 patients, including 981 IHD and 459 non-IHD subjects. A total of 43 patients with significant organic stenosis were excluded, and the remaining 416 patients with non-IHD or non-ob-CAD disease were assessed. ACh was injected in incremental doses of 20/50/80 μg into the right coronary artery (RCA) and 20/50/100/(200) μg into the left coronary artery (LCA). Positive coronary spasms were defined as transient luminal narrowing of >99%. Positive coronary spasms were noted in 17.3% of the non-IHDs patients (72/416), compared to 11.4% (15/132), 19% (8/42), 16.7% (5/30), 23.9% (16/67), and 19.3% (28/145), in the patients in the Aty, Val, HCM, CHF, and Oth groups, respectively. The rate of positive provoked spasms was higher in men than women, although not significantly [20.6% (46/223) vs. 13.4% (26/193), ns], and significantly higher in the late period (2001-2012) than in the early period (1991-2000) (36.8% vs. 7.0%, p<0.001).

CONCLUSION

Physicians should perform spasm provocation tests in patients with IHD as well as non-IHD with non-ob-CAD, as one of six non-IHD patients in this study exhibited provoked coronary spasms.

Gender differences in sensitivity of acetylcholine and ergonovine to coronary spasm provocation test

We examined the sex difference concerning the coronary artery response between ACh and ER in this study. We already reported the difference of coronary response between acetylcholine (ACh) and ergonovine (ER). We performed both ACh and ER tests of 461 patients (male 294 patients, female 167 patients, mean age 64.4 ± 11.3 years) during 23 years. Positive coronary spasm was defined as >99 % transient luminal narrowing with usual chest pain and/or ischemic ECG changes. Firstly, ACh was administered in incremental doses of 20/50/(80) μg into the RCA and 20/50/100/(200) μg into the LCA over 20 s. Secondly, ER was administered in a total dose of 40 μg into the RCA and of 64 μg into the LCA over 2-4 min. Intracoronary injection of ACh and ER provoked spasm in 221 patients consisting of 160 male patients and 61 female patients. In female patients, the spasm provoked by ACh was almost perfect except in two patients (59 patients, 96.7 %), while ER provoked spasm in only 20 patients (32.8 %). In male patients, provoked spasm by ACh (129 patients, 80.6 %) was significantly higher than ER (97 patients, 60.6 %). As a spasm provocation test, ACh is more sensitive than ER in both sexes and especially in females. We may select two pharmacological agents by sex differences to provoke coronary artery spasm in the cardiac catheterization laboratory in the future.

Complete definite positive spasm on acetylcholine spasm provocation tests: comparison of clinical positive spasm

In the clinical grounds, patients with ≥90 % luminal narrowing during acetylcholine (ACh) testing had variable response. We investigated ischemic findings and chest symptoms in patients with ≥90 % luminal narrowing when performing ACh tests, retrospectively. We performed 763 ACh tests over 13 years (2001-2013). We analyzed chest symptoms and positive ischemic ECG changes during ACh tests. More than 90 % luminal narrowing was found in 441 patients (57.8 %) including 355 patients in the right coronary artery (RCA) and 363 patients in the left coronary artery (LCA). Chest symptom was observed in 386 patients (87.5 %) including 293 patients in the RCA and 304 patients in the LCA. ST elevation was found in 161 patients including 110 in the RCA and 85 patients in the LCA, while ST depression was recognized in 146 patients including 119 patients in the RCA and 117 patients in the LCA. Three quarter of patients with ≥90 % luminal narrowing had significant ischemic ECG changes, whereas two-third of patients with ≥90 % luminal narrowing complained usual chest pain accompanied with significant ischemic ECG changes. Unusual chest symptom was complained in 7.3 % patients with ≥90 % luminal narrowing. Neither chest symptom nor ECG changes were found in 30 patients (6.8 %) with ≥90 % luminal narrowing. A third of these patients had ischemic findings on non-invasive tests before catheterization and six patients had subtotal or total occlusion. We should realize some limitation to define positive coronary spasm based on the ischemic ECG change and chest symptom during ACh tests.

Safety and optimal protocol of provocation test for diagnosis of multivessel coronary spasm

We examined the safety of acetylcholine (ACh) and ergonovine (ER) tests retrospectively and investigated the optimal protocol of provocation test for diagnosis of multivessel coronary spasm. We performed 1546 ACh tests and 1114 ER tests during 23 years. ACh was injected in incremental doses of 20/50/80 μg into the right coronary artery (RCA) and of 20/50/100/200 μg into the left coronary artery (LCA) over 20 s. ER was administered in total doses of 40 μg into the RCA and of 64 μg into the LCA over 2-4 min. When a coronary spasm was induced and did not resolve spontaneously within 3 min after the completion of ACh/ER injection, or when hemodynamic instability due to coronary spasms occurred, 2.5-5.0 mg of nitrate was administered into the responsible vessel. To relive provoked spasm, it is necessary to administer nitrate in 31 cases by ACh and in 76 cases by ER (2.0 vs. 6.8 %, p < 0.01) before another vessel attempts. Multivessel spasms were often observed in LCA testing than in RCA testing on both agents [ACh: 78.6 % (11/14) vs. 11.8 % (2/17), p < 0.001, ER: 37.8 % (14/37) vs. 20.5 % (8/39), ns]. Even after the administration of nitrates, positive coronary spasm was obtained in 21.1 % by ACh and 52.9 % by ER tests on another coronary artery. No irreversible complications were recognized on both tests. We should firstly perform spasm provocation tests in the LCA and we may be able to diagnose another vessel spasm by performing the complete spasm provocation tests after the administration of nitrates to relieve provoked spasm in the first attempt.

Maximal acetylcholine dose of 200 μg into the left coronary artery as a spasm provocation test: comparison with 100 μg of acetylcholine

As a spasm provocation test of acetylcholine (ACH), incremental dose up (20/50/100 μg) into the left coronary artery (LCA) is recommended in the guidelines established by Japanese Circulation Society. Recently, Ong et al. reported the ACOVA study which maximal ACH dose was 200 μg in the LCA. We compared the angiographic findings between ACH 100 μg and ACH 200 μg in the LCA and also examined the usefulness and safety of ACH 200 μg in Japanese patients without variant angina. As a spasm provocation test, we performed intracoronary injection of ACH 200 μg after ACH 100 μg in 88 patients (55 males, 68.4 ± 11.7 years old) including 59 ischemic heart disease (IHD) patients and 29 non-IHD patients. Positive spasm was defined as >99 % transient stenosis (focal spasm) or 90 % severe diffuse vasoconstriction (diffuse spasm). Positive spasm by ACH 200 μg was significantly higher than that by ACH 100 μg (36 pts: 40.9 % vs. 17 pts: 19.3 %, p < 0.01). Diffuse distal spasm on the left anterior descending artery was more recognized in ACH 200 μg than in ACH 100 μg (30.7 vs. 13.6 %, p < 0.01). In 29 rest angina patients, positive spasm by ACH 200 μg (19 pts) was significantly higher than that by ACH 100 μg (7 pts) (65.5 vs. 24.1 %, p < 0.01). No serious irreversible complications were found during ACH 200 μg. Administration of ACH 200 μg into the LCA was safe and useful. We may reexamine the maximal ACH dose into the LCA.

Severity of myocardial fatty acid dysmetabolism induced by coronary spasm does not differ with Thrombolysis in Myocardial Infarction (TIMI) grade during intracoronary acetylcholine provocation tests

Whether additional intracoronary acetylcholine (ACH) injections are required for severe coronary spasm without limited coronary flow in the ACH provocation test remains unclear. We used (123)I-β-methyl-iodophenyl pentadecanoic acid ((123)I-BMIPP) to identify myocardial ischemic memory to compare the severity of myocardial fatty acid dysmetabolism among Thrombolysis in Myocardial Infarction (TIMI) grade flow.Thirteen hypertensive volunteers (mean age, 69.5 years) and 37 patients with VSA (mean age, 62.8 years) were enrolled. The patients with VSA were stratified according to TIMI flow grades of 3 (90% luminal narrowing; n = 12) or TIMI 0-2 (≥ 99% or total occlusion; n = 25) during ACH provocation tests. Two weeks after cardiac catheterization, (123)I-BMIPP myocardial scintigraphic images were obtained at 15 minutes (early) and at 4 hours (delayed) after tracer injection. The heart-to-mediastinum (H/M) ratio and washout rates (WR) were calculated from planar images.The TIMI 3 and TIMI 0-2 groups had significantly lower early and delayed H/M ratios than controls but the difference did not reach significance between the two groups (Early: 2.7 ± 0.5 versus 2.3 ± 0.4 and 2.2 ± 0.3, P = 0.024; Delayed: 2.4 ± 0.4 versus 1.8 ± 0.3 and 1.8 ± 0.3, P = 0.001). The washout rate was greater for TIMI 0-2 than the controls.The severity of myocardial fatty acid dysmetabolism did not differ between TIMI 3 and TIMI 0-2 coronary spasms. Additional ACH might not be required considering safety and the severity of coronary spams with TIMI 3 grade flow.

Spasm provocation tests performed under medical therapy: a new approach for treating patients with refractory coronary spastic angina on emergency admission

Objective There are no objective methods for evaluating the severity of vasospasms in patients with refractory coronary spastic angina (R-CSA) under adequate medical therapy. We examined whether spasm provocation tests performed under adequate medication are useful for evaluating the severity of disease in R-CSA patients on emergency admission. Methods and Results We performed spasm provocation tests before and after the administration of medical therapy in eight R-CSA patients, including one ventricular fibrillation survivor (VF-S) and seven patients with unstable angina (UAP) on emergency readmission. We also performed these tests only after medical therapy on urgent admission in four R-CSA patients, including two patients with UAP, one patient with VF-S and one patient with acute coronary syndrome. All 12 R-CSA patients had been medicated with ≥ 2 vasodilator drugs. Positive coronary spasms were defined as >99% transient narrowing. The coronary artery spasms disappeared in three patients under medication, and mitigation of vasospasticity was observed in three patients. In these six cases we continued the same medications. Meanwhile in two patients, we recommended a consultation for psychosomatic medicine. In contrast, the remaining six R-CSA patients exhibited higher levels of vasospasticity, irrespective of the administration of aggressive medical therapy, in which the doses of vasoactive drugs were increased in order to suppress coronary artery spasms. Conclusion In some R-CSA patients on emergency admission, performing spasm provocation tests under medical therapy is useful for determining the subsequent treatment strategy. Therefore, this test may become a new tool in the treatment of R-CSA.

Provocative testing for coronary reactivity and spasm

Coronary spasm is an important and often overlooked etiology of chest pain. Although coronary spasm, or Prinzmetal's angina, has been thought of as benign, contemporary studies have shown serious associated adverse outcomes, including acute coronary syndrome, arrhythmia, and death. Definitive diagnosis of coronary spasm can at times be difficult, given the transience of symptoms. Numerous agents have been historically described for provocative testing. We provide a review of published data for the role of provocation testing in the diagnosis of coronary spasm.

Clinical implications of provocation tests for coronary artery spasm: safety, arrhythmic complications, and prognostic impact: multicentre registry study of the Japanese Coronary Spasm Association

AIMS

Provocation tests of coronary artery spasm are useful for the diagnosis of vasospastic angina (VSA). However, these tests are thought to have a potential risk of arrhythmic complications, including ventricular tachycardia (VT), ventricular fibrillation (VF), and brady-arrhythmias. We aimed to elucidate the safety and the clinical implications of the spasm provocation tests in the nationwide multicentre registry study by the Japanese Coronary Spasm Association.

METHODS AND RESULTS

A total of 1244 VSA patients (M/F, 938/306; median 66 years) who underwent the spasm provocation tests were enrolled from 47 institutes. The primary endpoint was defined as major adverse cardiac events (MACEs). The provocation tests were performed with either acetylcholine (ACh, 57%) or ergonovine (40%). During the provocation tests, VT/VF and brady-arrhythmias developed at a rate of 3.2 and 2.7%, respectively. Overall incidence of arrhythmic complications was 6.8%, a comparable incidence of those during spontaneous angina attack (7.0%). Multivariable logistic regression analysis demonstrated that diffuse right coronary artery spasm (P < 0.01) and the use of ACh (P < 0.05) had a significant correlation with provocation-related VT/VF. During the median follow-up of 32 months, 69 patients (5.5%) reached the primary endpoint. The multivariable Cox proportional hazard model revealed that mixed (focal plus diffuse) type multivessel spasm had an important association with MACEs (adjusted hazard ratio, 2.84; 95% confidence interval, 1.34-6.03; P < 0.01), whereas provocation-related arrhythmias did not.

CONCLUSION

The spasm provocation tests have an acceptable level of safety and the evaluation of spasm type may provide useful information for the risk prediction of VSA patients.

Therapeutic procedures for coronary vasospasm-induced polymorphic ventricular tachycardia

Coronary vasospasm is an unusual cause of angina and myocardial ischemia, with the potential to provoke acute myocardial infarction, malignant cardiac arrhythmias, and sudden cardiac death. The diagnosis is largely clinical and requires a high index of suspicion. Provocation studies are rarely performed due to the risks of the procedure and the relatively low incidence of disease. A subset of patients does not respond to conventional medical therapy and a paucity of evidence exists to guide therapy. While generally believed a multifocal phenomenon, there have been reports of successful treatment of focal, refractory vasospasm with coronary stent implantation. Furthermore, consideration of an implantable cardioverter defibrillator is warranted when vasospasm is complicated by lethal ventricular arrhythmias.

High prevalence of a pathological response to acetylcholine testing in patients with stable angina pectoris and unobstructed coronary arteries. The ACOVA Study (Abnormal COronary VAsomotion in patients with stable angina and unobstructed coronary arteries)

OBJECTIVES

This study aimed at determining the prevalence of epicardial and microvascular coronary spasm in patients with anginal symptoms, despite angiographically normal coronary arteries.

BACKGROUND

Despite a typical clinical presentation with exercise-related anginal symptoms (chest pain or dyspnea) with or without occasional attacks of resting chest pain suggestive of coronary artery disease, 40% of patients undergoing diagnostic angiography have normal or "near" normal coronary arteriograms. Many of these patients are given a diagnosis of noncardiac chest pain, and some are considered to have microvascular angina. However, we speculate that abnormal coronary vasomotion (reduced vasodilatation with exercise = reduced coronary flow reserve and/or vasospasm at rest) might also represent a plausible explanation for the symptoms of the patient.

METHODS

This was a prospective study in 304 consecutive patients (50% men, mean age 66 ± 10 years) with exertional anginal symptoms undergoing diagnostic angiography. A total of 139 patients (46%) had ≥50% coronary artery disease in at least 1 coronary artery, 21 patients (7%) had luminal narrowings ranging from >20% to 49%, and 144 patients (47%) had normal coronary arteries or only minimal irregularities (<20% diameter reduction).

RESULTS

One hundred twenty-four patients of the latter (86%) underwent intracoronary acetylcholine (ACH) testing, which elicited coronary spasm in 77 patients (62%), 35 patients (45%) with epicardial spasm (≥75% diameter reduction with reproduction of the symptoms of the patient) and 42 patients (55%) with microvascular spasm (reproduction of symptoms, ischemic electrocardiographic changes, and no epicardial spasm).

CONCLUSIONS

Nearly 50% of patients undergoing diagnostic angiography for assessment of stable angina had angiographically normal or near normal coronary arteriograms. The ACH test triggered epicardial or microvascular coronary spasm in nearly two-thirds of these patients. Our results suggest that abnormal coronary vasomotion plays a pathogenic role in this setting and that the ACH test might be useful to identify patients with cardiac symptoms, despite normal coronaries. (Abnormal Coronary Vasomotion in Patients With Suspected CAD But Normal Coronary Arteries; NCT00921856).

Enhanced Rho-kinase activity in circulating neutrophils of patients with vasospastic angina: a possible biomarker for diagnosis and disease activity assessment

OBJECTIVES

The aim of this study was to examine whether Rho-kinase activity is systemically enhanced in patients with vasospastic angina (VSA) and, if so, whether a noninvasive diagnostic method could be developed to improve practice.

BACKGROUND

The activated Rho-kinase pathway plays a central role in the molecular mechanism of coronary vasospasm in animal models and patients with VSA. Recently, it has been reported that Rho-kinase activity in circulating leukocytes is associated with various diseases.

METHODS

Fifty-three consecutive patients with chest pain who underwent acetylcholine provocation testing for coronary spasm were examined. Patients were divided into 2 groups depending on their response to the test: VSA (n = 33) and non-VSA (n = 20) groups. Venous blood samples were collected to measure Rho-kinase activity in circulating neutrophils, determined by the extent of phosphorylation of myosin-binding subunit (MBS), a substrate of Rho-kinase.

RESULTS

Rho-kinase activity was significantly higher in the VSA group than in the non-VSA group (phosphorylated MBS/total MBS ratio 1.33 ± 0.37 vs. 0.95 ± 0.22, p < 0.001). In the VSA group, no correlation was noted between Rho-kinase activity and high-sensitivity C-reactive protein, smoking, or accumulated number of coronary risk factors. After the 3-month medical treatment, Rho-kinase activity in the VSA group was significantly decreased to 1.08 ± 0.31 (p < 0.001). On receiver-operating characteristic curve analysis, a phosphorylated MBS ratio of 1.18 was identified as the best cutoff level to predict the diagnosis of VSA.

CONCLUSIONS

These results indicate that Rho-kinase activity in circulating neutrophils is enhanced in patients with VSA and may be a useful biomarker for diagnosis and disease activity assessment of the vasospastic disorder.

Vasospastic angina pectoris complicated by acute myocardial infarction and complete atrioventricular block

Background. A prolonged coronary artery spasm with interruption of coronary blood flow can lead to myocardial necrosis and increase of cardiospecific enzymes and can be complicated with cardiac rhythm disturbances, syncopc, or even sudden cardiac death. Case report. A 55-year old male felt a severe retrosternal pain when exposing himself to cold weather. The pain lasted for 20 minutes and was followed by the loss of conscience. Electrocardiogram (ECG) showed a complete antrioventricular (AV) block with nodal rhythm and marked elevation of ST segment in inferior leads. Electrocardiogram was soon normalized, but serum activities of cardiospecific enzymes were increased. Coronarography showed normal findings for the left coronary artery and a narrowing at the middle part of the right coronary artery, which disappeared after intracoronary application of nitroglycerine. The following therapy was prescribed: Diltiazem, Amlodipin, Isosorbid mononitrate, Molisdomin, Atrovastatin, Aspirin and Nitroglycerine spray. After 7 months medicaments were abandoned and the patient experienced again reccurent chest pain episodes at rest. Transitory ST segment elevation was recorded in inferior leads of ECG, but without increase of cardiospecific enzymes serum activities. After restoration of the medicament therapy anginal episodes ceased. Conclusion. Coronary dilators in maximal doses can prevent attacks of vasospastic angina.

Disruption of coronary vasomotor function: the coronary spasm syndrome

Abnormal coronary vasoconstriction, or coronary spasm, can be the result of several factors, including local and neuroendocrine aberrations. It can manifest clinically as a coronary syndrome and plays an important role in the genesis of myocardial ischemia. Over the past half century, coronary angiography allowed the in vivo demonstration of spasm in patients who fit the initial clinical description of the condition as reported by Prinzmetal et al. Several clinical, basic, and more recently, genetic studies have provided insight into the pathogenesis, manifestations, and therapy of this condition. It is not uncommonly encountered in patients with coronary syndromes and absence of clearly pathologic lesions on angiography. Provocation tests utilizing pharmacologic and nonpharmacologic stimuli combined with imaging (echocardiography or coronary angiography) can help make the correct diagnosis. The use of calcium channel blockers and long-acting nitrates is currently considered standard of care and the overall prognosis appears to be good. The recent discovery of genetic abnormalities predisposing to abnormal spasm of the coronaries has stimulated interest in the development of targeted therapies for the management of this condition.

Coronary abnormal response has increased in Japanese patients: analysis of 17 years' spasm provocation tests in 2093 cases

BACKGROUND

Abnormal coronary response on acetylcholine test is observed in patients with early coronary atherosclerosis.

OBJECTIVES

We analyzed retrospectively the abnormal response rate during 17 years of spasm provocation tests in 2093 consecutive patients.

METHODS

We performed 2093 spasm provocation tests, consisting of 1198 acetylcholine tests and 895 ergonovine tests, between January 1991 and December 2007. Spasm provocation test was mainly performed in patients with ischemic heart disease. Abnormal response was defined as transient >90% luminal narrowing during spasm provocation tests. We classified these 17 years into two periods: former period from January 1991 to December 2000, and the latter period from January 2001 to December 2007. In the former period, 1300 spasm provocation tests were performed and 793 spasm provocation tests were done in the latter period.

RESULTS

The incidences of hypertension, dyslipidemia, and diabetes mellitus were significantly increased in the latter period. The values of total cholesterol, triglycerides, and fasting blood sugar were also significantly increased in the latter period. The frequency of abnormal response in the latter period was significantly higher than that in the former period (46.0% vs. 33.2%, p<0.05). The frequency of abnormal coronary response to acetylcholine in the latter period was significantly higher than that in the former period (60.0% vs. 34.0%, p<0.01), whereas there was no difference concerning abnormal response of ergonovine between the two periods (31.9% vs. 30.7%, ns).

CONCLUSIONS

In Japanese patients, abnormal coronary response to acetylcholine has increased and coronary endothelial dysfunction is suggested to have progressed.

Vasospastic heart failure: multiple spasm may cause transient heart failure?

BACKGROUND

There have been no reports concerning the correlation between heart failure and coronary artery spasm.

METHODS AND RESULTS

From January 2000 to December 2007, 201 patients with heart failure were hospitalized at our institution. We could perform coronary arteriography and spasm provocation tests in 37 (22 men, 67±11 years) out of 201 patients with heart failure before discharge. Atrial fibrillation was observed in 13 patients (35%). After controlling heart failure and 24h cessation of vasoactive drugs, pharmacological spasm provocation tests were performed. Positive spasm was defined as >90%. Coronary spasm was observed in 12 patients (32%) and multiple spasm was recognized in 10 (83%) out of 12 patients. Though ejection fraction on admission was not different between the two groups (42±18% vs. 43±11%, ns), left ventricular end-diastolic and end-systolic dimension after medical therapy over 1 year was significantly smaller in patients with positive spasm than that in patients with negative spasm. There was no difference concerning medications except the administration of nitrate and nicorandil between two groups.

CONCLUSIONS

Coronary artery spasm, especially multiple spasm, may cause transient heart failure in a small part of unknown origin heart failure in Japan.

Recommendations for performing acetylcholine tests safely: STOP dangerous complications induced by acetylcholine tests (STOP DCIAT)

OBJECTIVES

We examined some recommendations for performing acetylcholine (ACh) tests safely.

METHODS AND RESULTS

We performed 1000 ACh tests from 1991 to December 2004. ACh was injected in incremental doses of 20/50/80 microg into the RCA and of 20/50/100 microg into the LCA. During these periods, we encountered various major/minor complications; 12 ventricular tachycardia (1.2%) necessary one dc, one ventricular fibrillation (0.1%) necessary dc, 3 shock like the left main stem spasm (0.3%), one cardiac tamponade necessary surgical drainage (0.1%), and 164 Paf (164/959:17.1%) necessary administration of antiarrhythmic agents to sinus rhythm in about one third patients (31.7%). We did not experience irreversible severe complications, such as acute myocardial infarction or death.

RECOMMENDATIONS

(1) Stand by direct current with pasting, (2) Thump version when ventricular tachycardia or fibrillation occurred, (3) Over infusion to avoid hypovolemia, (4) Perform angiography before complete spasm provocation if a severe spasm, (5) Drainage if cardiac tamponade occurred, (6) Cibenzoline or disopyramid administration when ACh induced paroxysmal atrial fibrillation, (7) Incremental ACh dose up should be performed, (8) Administer small amount of noradrenaline if shock observed and (9) Test shot should be performed before 1-min angiography.

CONCLUSIONS

We recommend STOP DCIAT for performing ACh tests safely.

A long-acting calcium antagonist over one year did not improve BMIPP myocardial scintigraphic imagings in patients with pure coronary spastic angina

BACKGROUND

Calcium antagonists (Ca) have been effective in reducing angina attacks in patients with variant angina. However, there are no reports regarding the effectiveness of Ca on myocardial fatty acid metabolic images in patients with pure coronary spastic angina (CSA).

OBJECTIVES

This study sought to examine the correlation between myocardial fatty acid metabolic images and the medical treatment of Ca in patients with pure CSA.

METHODS AND RESULTS

This study included 35 consecutive patients (28 men, mean age of 66 +/- 10 years) with angiographically confirmed coronary spasm and no fixed stenosis. Long-acting Ca was administered to all 35 patients. Isosorbide dinitrate /nicorandil/another Ca/beta-bloker were administered when chest pain was not controlled. Using an iodinated fatty acid analogue, 15-(p-[iodine-123]iodophenyl)-3-(R,S)methylpentadecanoic acid (BMIPP), myocardial scintigraphies with intravenous adenosine triphosphate infusion were performed before cardiac catheterization and 12 mo after medical therapy. According to the medical control states, these 35 patients were classified into 3 groups; response (disappearance of angina attacks, 12 pts, 60 +/- 11 years), partial response (angina attacks < 4/mo, 12 pts, 67 +/- 10 years), and no response to therapy (angina attacks > or = 4/mo, 11 pts, 71 +/- 6 years). Reduced BMIPP uptake was observed in 24 (69%) of 35 patients before the treatment. Reduced BMIPP uptake was also found in 18 patients (51%) after 12 mo. Normal BMIPP uptake after 12 mo therapy was observed in about half (response: 42%, partial response: 58%, no response: 45%) of patients among the 3 groups. There was no difference regarding the value of washout rate (WOR) (response; 10 +/- 7 (before), 14 +/- 8% (12 mo)), partial response; 11 +/- 7, 10 +/- 5%, no response; 13 +/- 9, 14 +/- 8%) among the 3 groups. The defect scores of BMIPP in the three groups were not different during at least one year medical therapy. No difference regarding the distribution of other medical therapies (angiotensin converting enzyme inhibitors/angiotensin receptor blockers/beta-blockers/statins) was found. The administration of Ca and isosorbide dinitrate/nicorandil and 2 Ca was significantly higher in the poor than in the good control patients.

CONCLUSIONS

Long-acting Ca over one year did not improve myocardial fatty acid metabolic images in patients with pure CSA. This may be related to silent ischemia.