Usefulness of accelerated exercise following mild hyperventilation for the induction of coronary artery spasm : comparison with an acetylcholine Test

Refractory vasospastic angina in a patient with autoimmune hepatitis managed by using combined non-invasive provocation tests: A case report

Corticosteroids have emerged as a feasible treatment option for patients with refractory vasospastic angina (VSA) who have an allergic disease or hypereosinophilia. However, reports on VSA following the administration of corticosteroids are scarce. Herein, we present the rare case of a 49-year-old Japanese man who developed VSA while receiving corticosteroids for treatment of autoimmune hepatitis. Invasive coronary angiography and pharmacological spasm provocation tests under oral prednisolone (20 mg) revealed multi-vessel spasms with ST elevation but no obstructed coronary arteries. To assess the effectiveness of the pharmacotherapy following a Ca2+ antagonist (benidipine) administration, we adopted non-invasive and non-pharmacological coronary vasospasm provocation tests (cold-pressor stress, isometric handgrip exercise, and hyperventilation). These tests revealed transient ST elevations with angina, which prompted us to add other vasodilators to control the high disease activity. These tests can be particularly valuable in cases where spasmogenicity fluctuates with changes in corticosteroid dosage during prolonged treatment of hepatitis.

Learning objective

Corticosteroids can induce vasospastic angina (VSA) and corticosteroid-induced VSA may relapse in a dose-dependent manner. Discontinuation of corticosteroids is often difficult, and long-term administration may be inevitable. Evaluation of the fluctuated spasmogenicity during long-term observation of autoimmune hepatitis may be crucial.

Noninvasive evaluation of dynamic microvascular dysfunction in ischemia and no obstructive coronary artery disease patients with suspected vasospasm

INTRODUCTION

In patients with ischemia and no obstructive coronary artery disease (INOCA), a dynamic coronary microvascular dysfunction (CMD) is frequent but difficult to capture by noninvasive means.The aim of our study was to assess dynamic CMD in INOCA patients with stress echocardiography after vasoconstrictive and vasodilator stimuli.

METHODS

In this prospective single-center study, we have enrolled 40 INOCA patients (age 56.3 ± 13 years, 32 women). All participants underwent stress echocardiography with hyperventilation (HYP), followed by supine bicycle exercise (HYP+EXE) and adenosine (ADO). Stress echocardiography included an assessment of regional wall motion abnormality (RWMA) and coronary flow velocity (CFV) in the distal left anterior descending (LAD) coronary artery.

RESULTS

HYP induced a 30% increase in rate pressure product (rest = 10 244 ± 2353 vs. HYP = 13 214 ± 3266 mmHg x bpm, P  < 0.001) accompanied by a paradoxical reduction in CFV (HYP< rest) in 21 patients (52%). HYP alone was less effective than HYP+EXE in inducing anginal pain (6/40, 15% vs. 10/40, 25%, P  = 0.046), ST segment changes (6/40, 15% vs. 24/40, 60%, P  < 0.001), and RWMA (6/40, 15% vs. 13/40, 32.5%, P  = 0.008). ADO-induced vasodilation was preserved (≥2.0) in all patients.

CONCLUSION

In patients with INOCA, a coronary vasoconstriction after HYP is common, in absence of structural CMD detectable with ADO. HYP+EXE test represents a more powerful ischemia inducer than HYP alone. Stress echocardiography with LAD-CFV may allow the noninvasive assessment of dynamic and structural coronary microcirculation during stress.

Stress Echo 2030: The Novel ABCDE-(FGLPR) Protocol to Define the Future of Imaging

With stress echo (SE) 2020 study, a new standard of practice in stress imaging was developed and disseminated: the ABCDE protocol for functional testing within and beyond CAD. ABCDE protocol was the fruit of SE 2020, and is the seed of SE 2030, which is articulated in 12 projects: 1-SE in coronary artery disease (SECAD); 2-SE in diastolic heart failure (SEDIA); 3-SE in hypertrophic cardiomyopathy (SEHCA); 4-SE post-chest radiotherapy and chemotherapy (SERA); 5-Artificial intelligence SE evaluation (AI-SEE); 6-Environmental stress echocardiography and air pollution (ESTER); 7-SE in repaired Tetralogy of Fallot (SETOF); 8-SE in post-COVID-19 (SECOV); 9: Recovery by stress echo of conventionally unfit donor good hearts (RESURGE); 10-SE for mitral ischemic regurgitation (SEMIR); 11-SE in valvular heart disease (SEVA); 12-SE for coronary vasospasm (SESPASM). The study aims to recruit in the next 5 years (2021-2025) ≥10,000 patients followed for ≥5 years (up to 2030) from ≥20 quality-controlled laboratories from ≥10 countries. In this COVID-19 era of sustainable health care delivery, SE2030 will provide the evidence to finally recommend SE as the optimal and versatile imaging modality for functional testing anywhere, any time, and in any patient.

Impact of a correct breathing stereotype on pulmonary minute ventilation, blood gases and acid-base balance in post-myocardial infarction patients

STUDY OBJECTIVE

The aim of the study was to evaluate the impact of a long-term (6-month) correct breathing stereotype on minute ventilation, capillary blood gases and acid-base balance in post-myocardial infarction patients.

METHODS

Fifty-five men (age 57.2 +/- 12.5) were examined 2 months later after myocardial infarction. Spirometry and assessment of acid-base balance and capillary blood gases were performed at rest and repeated after 10 days and 6 months. Breathing correction was taught over 5 days. A session for the control and maintenance of the correct breathing skills was hosted once a month (during the 6-month period).

RESULTS

Changes of minute ventilation, capillary blood gases and acid-base balance were revealed in 55% of patients 2 months later after myocardial infarction. Twenty patients (group I) were randomly selected for breathing correction while 10 patients made up the control group (group II). After breathing correction minute ventilation significantly decreased (18.5 +/- 5.5 versus 9.8 +/- 2.5 l/min), oxygen ventilatory equivalent decreased (39.8 +/- 5.2 versus 22.5 +/- 3.8), partial pressure of blood carbon dioxide increased (33.2 +/- 1.7 versus 44.2 +/- 2.5 mmHg), plasma bicarbonate concentration augmented (19.1 +/- 2.2 versus 24.5 +/- 1.8 mmol/l), base excess normalized (-2.90 +/- 2.5 versus +1.3 +/- 2.1 mmol/l), and pH shifted to more alkaline value (7.36 +/- 0.01 versus 7.43 +/- 0.02).

CONCLUSIONS

A long-term correct breathing stereotype improved respiratory function and could be an additional measure in rehabilitation programmes for post-myocardial infarction patients.

Approximately half of patients with coronary spastic angina had pathologic exercise tests

OBJECTIVES

We examined the clinical usefulness of treadmill exercise tests (TETs) in diagnosing coronary spastic angina (CSA).

METHODS

We performed the TETs and 24-h Holter monitoring in 300 CSA patients consisting of 152 patients with rest angina, 77 patients with effort angina, and 71 patients with rest and effort angina. Organic stenosis (>75%) was observed in 44 patients. Multiple spasms were recognized in 204 patients (68%).

RESULTS

Positive TETs were recognized in 113 patients (38%) and borderline was observed in 30 patients (10%). Positive response was significantly higher in patients with organic stenosis than those without fixed stenosis (63.6% vs. 33.2%, p<0.001). Moreover, ST elevation was more frequent in patients with organic stenosis than those without fixed stenosis (27.3% vs. 1.2%, p<0.001). Positive response in patients with effort angina (46.8%) was higher than those in patients with rest angina (33.6%) and rest and effort angina (36.6%), but not significant. Positive response was not different between single spasm and multiple spasms. In all 300 patients, ST segment elevation was observed in only four patients (1.3%) on the 24-h Holter monitoring.

CONCLUSIONS

TET was useful in documenting ischemia in patients with CSA. More than a third of patients with CSA had positive TETs. Moreover, we obtained the pathologic TET response in approximately half of patients with CSA.

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.

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.

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.

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.

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.

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.

Severe spontaneous three-vessel coronary artery spasm

Coronary artery spasm is usually defined as a focal constriction of a coronary artery segment, reversible, and causing myocardial ischaemia by coronary blood flow restriction. Sometimes this condition is not focal and can compromise all the coronary tree. This is a very rarely described event. Generally, coronary vasospasm may occur spontaneously or induced, either physically by catheter, physiological manoeuvres (hyperventilation), or by pharmacological agents. It may also occur with or without underlying atheromatous coronary disease. The mechanism of coronary spasm remains unclear but endothelial dysfunction seems to be the main triggering factor in all causes.

Need for documentation of guidelines for coronary artery spasm: an investigation by questionnaire in Japan

BACKGROUND

Because there are no guidelines concerning coronary spasm in Japan, the present study examined the current status of the spasm provocation test.

METHODS AND RESULTS

Questionnaires concerning the number of cases of coronary angiography, percutaneous coronary intervention, and invasive/non-invasive spasm provocation tests over 3 years (2001-2003) and the status of spasm provocation tests were sent to members of the Japanese Circulation Society in 120 cardiology hospitals in the Chugoku and Shikoku areas. Completed surveys were returned from 45 hospitals, giving a collection rate of 38%. As a spasm provocation agent, acetylcholine tests were performed in 29 hospitals, and ergonovine tests in 18 hospitals. Non-invasive spasm provocation tests were performed in only 9 hospitals (20%). In total, 5,267 patients underwent acetylcholine spasm provocation test (2,387 patients) or ergonovine spasm provocation test (2,880 patients) and vasospastic angina was diagnosed in 1,663 (2.4%) patients. Invasive spasm provocation tests were performed in 7.8% of patients with diagnostic catheterization and the spasm-positive rate was 31.6%. The difference among hospitals concerning the number of invasive spasm provocation tests was remarkable, and the angiographic spasm-positive standard and acetylcholine/ergonovine dose varied among the hospitals.

CONCLUSIONS

Guidelines on coronary spasm in Japan are essential to overcome the current differences between institutions.

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.

Coronary vasospasm and the regulation of coronary blood flow

Under physiologic conditions, epicardial arteries contribute minimally to coronary vascular resistance. However, in the presence of endothelial dysfunction, stimuli that normally produce vasodilation may instead cause constriction. Examples include neural release of acetylcholine or norepinephrine, platelet activation and production of serotonin and thrombin, and release of local factors such as bradykinin. This shift from a primary endothelial-mediated vasodilator influence to one of endothelial dysfunction and unchecked vasoconstriction is precisely the milieu in which coronary vasospasm is observed. This condition, which typically occurs during periods of relatively sedentary activity, is associated with focal and transient obstruction of an epicardial arterial segment resulting in characteristic echocardiographic changes and symptoms of myocardial ischemia. This review highlights the current understanding of mechanisms regulating the coronary circulation during health and examines the pathophysiologic changes that occur with coronary spasm. Genetic and other predisposing conditions are addressed, as well as novel therapies based on recent mechanistic insights of the coronary contractile dysfunction associated with coronary spasm.

Did the Widespread Use of Long-Acting Calcium Antagonists Decrease the Occurrence of Variant Angina?

BACKGROUND

We have not often encountered variant angina (VA) since the use of long-acting calcium antagonists (L-CAs) became widespread.

OBJECTIVES

This study examined the frequency of VA retrospectively.

METHODS

and results: We diagnosed angiographically confirmed coronary spastic angina (CSA) in 349 consecutive patients using selective spasm provocation tests from January 1991 to December 2002. During this period, 3,148 diagnostic cardiac catheterizations and 1,515 selective spasm provocation tests were performed. Seventy-four of these 349 patients (21.2%) had VA. Coronary spasms were defined as transient luminal narrowings of > 99%, and VA was defined as an ST elevation during spontaneous attacks or noninvasive stress tests. We classified the 12 years of the study into four periods of 3 years each. No tendency to decrease for the ratio of the number of patients with CSA and the number of selective spasm provocation tests was observed among the four time periods (18%, 24%, 32%, and 23%, respectively). However, the number of patients with VA (28, 33, 9, and 4) and the VA/CSA ratio (32%, 28%, 14%, and 5%, respectively) in the four group significantly decreased. The frequency of administration of calcium antagonists (CAs) before hospital admission (49% vs 33%, respectively; p < 0.05) was significantly higher in the last time period (from 2000 to 2002) than in the first period (from 1991 to 1993). L-CAs were administered in > 90% of CSA patients who had been medicated with CAs before hospital admission in the last period (from 2000 to 2002), while L-CAs were administered in only 20% in the former period (from 1991 to 1993). The administration of statins and angiotensin-converting enzyme inhibitors/angiotensin receptor blockers before hospital admission gradually increased according to the period passed, but not significantly.

CONCLUSION

The frequency of VA has decreased in Japan, possibly due to the widespread use of therapy with L-CAs.

Coronary flow reserve in patients with vasospastic angina: correlation between coronary flow reserve and age or duration of angina

OBJECTIVES

This study sought to assess the coronary flow reserve (CFR) in patients with pure vasospastic angina (VSA).

METHODS AND RESULTS

The phasic flow velocities of both spasm-positive and spasm-negative coronary arteries of the left anterior descending artery (LAD) were recorded at rest and during hyperaemia (50 microg of adenosine triphosphate infusion intracoronary) using a 0.014 inch, 15 MHz Doppler guide wire in 42 patients with pure VSA and acetylcholine (ACh)-induced coronary artery spasms (20-100 microg), and 23 controls with normal coronary arteries without ACh-induced vasospasm. These 42 patients had 16 vessels with focal spasms (>99%), 17 vessels with diffuse spasms (>90%) in the LAD, and nine vessels with ACh-induced spasms in the right coronary artery, but not the LAD. Coronary flow reserve was obtained from the ratio of the hyperaemic/baseline time-averaged peak velocity. Coronary flow reserve did not differ between patients with VSA and the controls (2.9+/-0.8 versus 3.2+/-0.7, NS). Moreover, CFR did not differ among the four cases (focal: 2.8+/-0.7; diffuse: 3.0+/-0.9; non spasm: 2.9+/-0.7 versus controls: 3.2+/-0.7, respectively, NS). Coronary flow reserve in vessels with proximal spasms was significantly higher than that in vessels with mid or distal spasms (3.4+/-0.8 versus 2.6+/-0.6, 2.6+/-0.9, p<0.05). The only significant correlation was between CFR and age (p=0.0275) or the duration of angina before admission (p=0.0405).

CONCLUSIONS

There was no difference in CFR in patients with ACh-induced spasms between the spasm-positive and spasm-negative vessels. Moreover, CFR was maintained normally in vessels with diffuse spasms, as in those with focal spasms. The most important determinant factors for CFR in patients with VSA were age and the duration of angina before admission.

Induction of coronary artery spasm by two pharmacological agents: comparison between intracoronary injection of acetylcholine and ergonovine

BACKGROUND AND OBJECTIVES

There have been few studies comparing the clinical usefulness for the induction of coronary artery spasm (CAS) between acetylcholine (ACh) and ergonovine (ER). This study is designed: (1) to examine the duration of effect after intracoronary injection of ACh on the responsible vessels using a 0.014 inch, 15 MHz Doppler guide wire, and (2) to evaluate the efficacy of two pharmacological agents, ACh and ER, for the induction of CAS in patients with <50% stenosis in the cardiac laboratory.

METHODS

Phasic coronary flow velocity patterns were recorded at rest and during ACh tests in 22 patients with normal or near-normal coronary arteries. The tip of the guide wire was placed on the proximal right coronary artery (RCA) and mid-left anterior descending artery. We measured the time required to baseline level of average peak velocity after intracoronary injection of ACh. We performed selective intracoronary administration of both ER and ACh in the same 171 patients (106 men, 65 women, mean age of 62+/-10 years) with <50% stenosis. Under no medication, ACh was injected first in incremental doses of 20, 50, and 80 microg into the RCA and of 20, 50, and 100 microg into the left coronary artery (LCA). Ten minutes later, ER was administered at 10 microg/min for four minutes for a maximal dose of 40 microg on the RCA and at 16 microg/min over four minutes for a total dose of 64 microg on the LCA. Positive spasm was defined as > or =99% luminal narrowing.

RESULTS

The time-averaged peak velocity returned to baseline after intracoronary injection of ACh within 10 minutes in all 120 procedures, consisted of 19 with positive spasm (RCA (n=10): 245+/-33 s; LCA (n=9): 351+/-187 s) and 101 with negative spasm (RCA (n=48): 155+/-62 s, LCA (n=53): 248+/-106 s). In the overall results, there was no difference concerning the incidence of provoked spasm between the two pharmacological agents (ACh: 33% versus ER: 32%, NS). Coronary spasms were induced by either pharmacological agent in 134 vessels. Concordance in this study was 94% in all vessels, whereas the remaining 6% of vessels were different from each other. The non-concordance rate of the right coronary artery was significantly higher than that of the left coronary artery (10% versus 4%, p<0.01). However, ER provoked more focal spasms, whereas ACh provoked more diffuse and distal spasms, compared with each other. Seventy-four (55%) of the 134 vessels had coronary spasms in the same coronary arteries. Concordance of both provoked spasm sites and spasm configurations in the same coronary artery was observed in only 18 (13%) vessels. No serious or irreversible complications were observed during the two sequential tests.

CONCLUSIONS

As a spasm provocation test, there were no differences between ACh and ER. We recommend the supplementary use of these two pharmacological agents for the induction of CAS in the cardiac laboratory, if available.

Limitations of medical therapy in patients with pure coronary spastic angina

OBJECTIVES

To assess the efficacy of medication for the treatment of pure coronary spastic angina, 71 consecutive patients with this diagnosis who had undergone coronary arteriography in a hospital with a follow-up of at least 2 years were studied.

METHODS AND RESULTS

All 71 patients without significant organic stenosis were treated with long-acting calcium antagonists. The disappearance of chest pain attacks while receiving medical therapy was observed in 27 patients (38%), whereas the remaining 44 patients (62%) had chest pain attacks. Of special interest, 30 patients had more than one attack per month irrespective of the administration of calcium antagonists or isosorbide dinitrate. Medical treatment showed a good response in female patients (63% vs 31%, respectively; p < 0.05) and those with ST-segment elevation during selective spasm provocation tests (63% vs 30%, respectively; p < 0.05). In contrast, patients with a longer history of chest pain attacks before hospital admission and those with diffuse spasms (77% vs 34%, respectively; p < 0.01) had poor responses to medical treatment. In this study, neither sudden death nor acute myocardial infarction was observed during the follow-up periods.

CONCLUSION

The limitations of medical therapy, including the administration of long-acting calcium antagonists, were observed in 30 of 71 patients (42%) with pure coronary spastic angina. Medical treatment was effective in only 38% of patients with pure coronary spastic angina in Japan.

Intracoronary administration of a thromboxane A2 synthase inhibitor relieves acetylcholine-induced coronary spasm

This study sought to clarify the effectiveness of intracoronary administration of a thromboxane (TX) A2 synthase inhibitor, Ozagrel Na, to relieve coronary spasms induced by intracoronary injection of acetylcholine (ACh). An ACh spasm provocation test was performed in 92 consecutive patients with coronary spastic angina using incremental doses of 20, 50, and 80 microg into the right coronary artery, and 20, 50, and 100 microg into the left coronary artery within 20s. A coronary spasm was defined as TIMI 0 or 1 flow and an intracoronary injection of 20 mg Ozagrel Na was administered when it was provoked. Within 2 min of the administration of the TXA2 synthase inhibitor, ACh-induced coronary spasms were relieved (TIMI 3 flow) in 88.1% of procedures without complications. In only 4 cases (4.3%), it took more than 3 min to relieve the coronary spasms. Intracoronary administration of 20mg Ozagrel Na when ACh-induced spasms occurred, shortened the spasm relief time in all 7 patients (200 +/- 59s vs 111 +/- 23s, p < 0.01), improved the maximal ST segment elevation in 5 of them (3.9 +/- 3.7 mm vs 0.7 +/- 1.5 mm, p < 0.05), and stopped chest pain in 4 patients. In 4 patients who had ACh-induced coronary spasm of the left anterior descending artery, the TXB2 concentration in the coronary sinus decreased after intracoronary administration of Ozagrel Na into the left coronary artery (463 +/- 562 vs 96 +/- 45, p < 0.01). In conclusion, intracoronary administration of a TXA2 synthase inhibitor can relieve ACh-induced coronary spasms by inhibiting TXA2 synthesis in the local coronary circulation.

New protocol to detect coronary spastic angina without fixed stenosis

A new combined test, accelerated exercise following mild hyperventilation (HV), was examined to determine whether it is effective at detecting a positive response in patients with pharmacologically-induced coronary vasospasm and near normal coronary arteries. Fifty-eight consecutive patients who underwent both triple non-invasive spasm provocation tests and diagnostic coronary angiography were enrolled. They all had pharmacologically-induced coronary vasospasms and no significant organic stenosis. In these patients, an HV test was performed first, followed by a treadmill exercise test (TET), and finally the new combined test under no medication within 3 days. Of the 58 patients, positive responses were observed in 9 patients to the HV, in 15 to the TET, and in 35 to the newly combined test. The remaining 21 patients had negative responses although the triple sequential tests were perfomed. Thus, the sensitivities of the HV test, TET, and newly combined test were 16% (9/58), 26% (15/58), and 63% (35/56), respectively. Forty-six subjects with near normal coronary arteries and no ACh-provoked spasm served as controls. None of these subjects had positive responses to any of these three tests, and thus their specificity was all 100%. No serious or irreversible complications were seen in this study. We recommend this newly-combined protocol for the induction of coronary artery spasm in patients with vasospastic angina pectoris and without significant stenosis as a diagnostic tool.

Clinical and angiographical characteristics of acetylcholine- induced spasm: relationship to dose of intracoronary injection of acetylcholine

OBJECTIVES

The purpose of this study was to clarify clinical and angiographical characteristics of acetylcholine (ACh)-induced spasm in the right and left coronary artery.

METHODS AND RESULTS

We performed 557 consecutive procedures of spasm provocation tests of ACh from January 1991 to December 2000 in patients without significant stenosis. ACh was injected in incremental doses of 20, 50 and 80 microg into the right coronary artery and in incremental doses of 20, 50 and 100 microg into the left coronary artery if spasm had not been provoked. Coronary spasm was defined as positive with more than 99% transient luminal narrowing. Proximal spasm was defined as that of segments 1, 2, 5, 6, 7 and 11 and distal spasm as that of segments 3, 4, 8, 9, 12, 13 and 14. Low-ACh-dose-induced spasms showed the clinical findings and angiographical characteristics of higher incidence of variant angina, proximal spasms, focal spasms, more ST elevation and ischemic heart disease. In contrast, angiographical characteristics of high-Ach-dose-induced spasms were distal spasms and diffuse spasms and there was less variant angina and less ST elevation.

CONCLUSIONS

Lower ACh doses induced spasms more proximally and focally in the coronary artery, while higher doses of ACh provoked spasms more distally and diffusely.

Magnesium deficiency in patients with recent myocardial infarction and provoked coronary artery spasm

This study sought to clarify the relationship between magnesium (Mg) deficiency and coronary artery spasm provoked by pharmacologic agents in patients with a recent acute myocardial infarction (AMI). Twenty-three consecutive patients suffering from AMI were investigated with a Mg retention test (Mg: 0.1 mmol/kg for 4 h) in both the acute phase (within I week (3+/-2 days) of onset) and the subacute phase (3-4 weeks (24+/-6 days) of the onset). Early coronary arteriography was performed in all patients. Coronary stenosis in the infarct-related artery was less than 90% in all patients in the subacute phase. The spasm provocation test was performed in the subacute phase and coronary spasm was defined as transient subtotal or total occlusion in association with angina or electrocardiographic ST-segment deviation. Coronary artery spasm was provoked in only 13 of the 23 patients. Compared with the control subjects (12 patients without coronary artery disease or coronary spasm), the 24-h Mg retention was significantly higher in patients with AMI (acute phase: 78+/-27%, subacute phase: 66+/-32%, vs control: 48+/-12%, p<0.05). In the subacute phase, the 24-h Mg retention decreased in patients without coronary spasm (43+/-26%), but a high level of Mg retention was still observed in patients with coronary spasm (84+/-25%). There was no difference in the serum concentrations of Mg, calcium and phosphorus between the 2 groups on both phases. In conclusion, both Mg deficiency and provoked coronary artery spasm were noted in more than half of the Japanese patients with a recent AMI, suggesting a close association between Mg deficiency and AMI.

New non-invasive protocol for detection of coronary spastic angina with significant organic stenosis

OBJECTIVES

This study sought to determine whether a newly-combined test, accelerated exercise following mild hyperventilation (HV) is more beneficial to detect ischaemic evidence in patients with pharmacology-induced coronary artery spasm (CAS) and luminal narrowing of > 75% than classic methods.

METHODS AND RESULTS

Forty consecutive patients who all had luminal narrowing of > 75% but < 90% and pharmacology-induced coronary vasospasms of fixed lesions were involved in this study. In these patients, initial HV test, followed by treadmill (TM) exercise test and lastly the newly combined test were performed on three consecutive days. Of the 40 patients, firstly six, secondarily 16 and lastly 32 had positive responses to the HV test, TM exercise test, and newly combined test, respectively. The remaining six patients (15%) had negative results, although the triple sequential tests were performed. Thus, sensitivity of the HV test, the TM exercise test, and the newly combined test was 15% (6/40), 40% (16/40), and 84% (32/38), respectively. Specificity of the three tests were all 100% (46/46). Non-sustained ventricular tachycardia and hypotension were observed in two (5%) patients. However, no serious or irreversible complications were encountered in this study.

CONCLUSIONS

We recommend the newly combined protocol rather than the classic tests for the detection of ischaemic evidence in patients with coronary spastic angina and fixed stenosis.