Phosphorylated CPI-17 and MLC2 as Biomarkers of Coronary Artery Spasm-Induced Sudden Cardiac Death.

Coronary artery spasm (CAS) plays an important role in the pathogeneses of various ischemic heart diseases and has gradually become a common cause of life-threatening arrhythmia. The specific molecular mechanism of CAS has not been fully elucidated, nor are there any specific diagnostic markers for the condition. Therefore, this study aimed to examine the specific molecular mechanism underlying CAS, and screen for potential diagnostic markers. To this end, we successfully constructed a rat CAS model and achieved in vitro culture of a human coronary-artery smooth-muscle cell (hCASMC) contraction model. Possible molecular mechanisms by which protein kinase C (PKC) regulated CAS through the C kinase-potentiated protein phosphatase 1 inhibitor of 17 kDa (CPI-17)/myosin II regulatory light chain (MLC2) pathway were studied in vivo and in vitro to screen for potential molecular markers of CAS. We performed hematoxylin and eosin staining, myocardial zymogram, and transmission electron microscopy to determine myocardial and coronary artery injury in CAS rats. Then, using immunohistochemical staining, immunofluorescence staining, and Western blotting, we further demonstrated a potential molecular mechanism by which PKC regulated CAS via the CPI-17/MLC2 pathway. The results showed that membrane translocation of PKCα occurred in the coronary arteries of CAS rats. CPI-17/MLC2 signaling was observably activated in coronary arteries undergoing CAS. In addition, in vitro treatment of hCASMCs with angiotensin II (Ang II) increased PKCα membrane translocation while consistently activating CPI-17/MLC2 signaling. Conversely, GF-109203X and calphostin C, specific inhibitors of PKC, inactivated CPI-17/MLC2 signaling. We also collected the coronary artery tissues from deceased subjects suspected to have died of CAS and measured their levels of phosphorylated CPI-17 (p-CPI-17) and MLC2 (p-MLC2). Immunohistochemical staining was positive for p-CPI-17 and p-MLC2 in the tissues of these subjects. These findings suggest that PKCα induced CAS through the CPI-17/MLC2 pathway; therefore, p-CPI-17 and p-MLC2 could be used as potential markers for CAS. Our data provide novel evidence that therapeutic strategies against PKC or CPI-17/MLC2 signaling might be promising in the treatment of CAS.

Ponatinib-Related Vasospastic Angina.

Tyrosine kinase inhibitors (TKIs) are essential drugs for chronic myeloid leukemia and Philadelphia chromosome-positive acute lymphoblastic leukemia. Cardiovascular or arteriothrombotic adverse events have been reported in patients treated with TKIs. We report 3 cases of Ponatinib-related vasospastic angina, in which prophylactic administration of nitrates or calcium channel blockers was effective.

A Case of Ventricular Fibrillation in Masked Long-QT Syndrome Coexisting with Coronary Vasospasm.

Although long-QT syndrome (LQTS) with a normal range QT interval at rest leads to fatal ventricular arrhythmias, it is difficult to diagnose. In this article, we present a rare case of a patient who suffered a cardiac arrest and was recently diagnosed with LQTS and coronary vasospasm. A 62-year-old man with no syncopal episodes had a cardiopulmonary arrest while running. During coronary angiography, vasospasm was induced and we prescribed coronary vasodilators, including calcium channel blockers. An exercise stress test was performed to evaluate the effect of medications and accidentally unveiled exercise-induced QT prolongation. He was diagnosed with LQTS based on diagnostic criteria. Pharmacotherapy and an implantable cardioverter defibrillator were used for his medical management. It is extremely rare for LQTS and coronary vasospasm to coexist. In cases of exercise-induced arrhythmic events, the exercise stress test might be helpful to diagnose underlying disease.

Predicting the response to acetylcholine in ischemia or infarction with non-obstructive coronary arteries: The ABCD score.

BACKGROUND AND AIMS: Acetylcholine (ACh) provocation testing can detect vasomotor disorders in patients with ischemia and non-obstructed coronary arteries (INOCA) or myocardial infarction and non-obstructed coronary arteries (MINOCA). We aimed to derive and validate a simple risk score to predict a positive ACh test response. METHODS: We prospectively enrolled consecutive INOCA and MINOCA patients undergoing ACh provocation testing. Patients were split in two cohorts (derivation and validation) according to time of enrolment. The score was derived in 386 patients (derivation cohort) and then validated in 165 patients (validation cohort). RESULTS: 551 patients were enrolled, 371 (67.3%) INOCA and 180 (32.7%) MINOCA. ACh test was positive in 288 (52.3%) patients. MINOCA, myocardial bridge (MB), C-reactive protein (CRP) and dyslipidaemia were independent predictors of a positive ACh test in the derivation cohort. The ABCD (Acute presentation, Bridge, CRP, Dyslipidaemia) score was derived: 2 points were assigned to MINOCA, 3 to MB, 1 to elevated CRP and 1 to dyslipidaemia. The ABCD score accurately identified patients with a positive ACh test response with an AUC of 0.703 (CI 95% 0.652-0.754,p < 0.001) in the derivation cohort, and 0.705 (CI 95% 0.626-0.784, p < 0.001) in the validation cohort. In the whole population, an ABCD score ≥4 portended 94.3% risk of a positive ACh test and all patients with an ABCD score ≥6 presented a positive test. CONCLUSIONS: The ABCD score could avoid the need of ACh provocation testing in patients with a high score, reducing procedural risks, time, and costs, and allowing the implementation of a tailored treatment strategy. These results are hypothesis generating and further research involving larger cohorts and multicentre trials is needed to validate and refine the ABCD score.

Recurrent syncope due to ischemia with non-obstructive coronary artery disease: a case report.

BACKGROUND: Ischemia with non-obstructive coronary artery disease is a prevalent form of ischemic heart disease. The majority of ischemia with non-obstructive coronary artery disease cases are attributed to underlying factors such as coronary microvascular dysfunction (CMD) and/or coronary artery spasm. Ischemia with non-obstructive coronary artery disease can present with various clinical manifestations. Recurrent syncope is an atypical complaint in patients with ischemia with non-obstructive coronary artery disease. CASE PRESENTATION: This case report describes the presentation of a 58-year-old Chinese male patient who experienced repeated episodes of syncope. The syncope was found to be caused by concomitant coronary artery spasm and presumptive coronary microvascular dysfunctionc suggested by "slow flow" on coronary angiography. The patient was prescribed diltiazem sustained-release capsules, nicorandil, and atorvastatin. During the three-month follow-up conducted on our outpatient basis, the patient did not experience a recurrence of syncope. CONCLUSION: This study highlights the importance of considering ischemia with non-obstructive coronary artery disease as a potential cause of syncope in the differential diagnosis. It emphasizes the need for early diagnosis of ischemia with non-obstructive coronary artery disease to facilitate more effective management strategies.

Comparison of the Diagnostic Yield of Intracoronary Acetylcholine Infusion and Acetylcholine Bolus Injection Protocols During Invasive Coronary Function Testing.

Coronary endothelial dysfunction (CED) and coronary artery spasm (CAS) are causes of angina with no obstructive coronary arteries in patients. Both can be diagnosed by invasive coronary function testing (ICFT) using acetylcholine (ACh). This study aimed to evaluate the diagnostic yield of a 3-minute ACh infusion as compared with a 1-minute ACh bolus injection protocol in testing CED and CAS. We evaluated 220 consecutive patients with angina and no obstructive coronary arteries who underwent ICFT using continuous Doppler flow measurements. Per protocol, 110 patients were tested using 3-minute infusion, and thereafter 110 patients using 1-minute bolus injections, because of a protocol change. CED was defined as a <50% increase in coronary blood flow or any epicardial vasoconstriction in reaction to low-dose ACh and CAS according to the Coronary Vasomotor Disorders International Study Group (COVADIS) criteria, both with and without T-wave abnormalities, in reaction to high dose ACh. The prevalence of CED was equal in both protocols (78% vs 79%, p = 0.869). Regarding the endotypes of CAS according to COVADIS, the equivocal endotype was diagnosed less often in the 3 vs 1-minute protocol (24% vs 44%, p = 0.004). Including T-wave abnormalities in the COVADIS criteria resulted in a similar diagnostic yield of both protocols. Hemodynamic changes from baseline to the low or high ACh doses were comparable between the protocols for each endotype. In conclusion, ICFT using 3-minute infusion or 1-minute bolus injections of ACh showed a similar diagnostic yield of CED. When using the COVADIS criteria, a difference in the equivocal diagnosis was observed. Including T-wave abnormalities as a diagnostic criterion reclassified equivocal test results into CAS and decreased this difference. For clinical practice, we recommend the inclusion of T-wave abnormalities as a diagnostic criterion for CAS and the 1-minute bolus protocol for practicality.

Long-term prognostic factors for cardiovascular events in patients with chest pain without diabetes mellitus nor significant coronary stenosis.

Chest pain is the most common symptom of coronary artery disease (CAD) and diabetes mellitus (DM) is a well-known single strongest risk factor for cardiovascular diseases. Thus, the impact of CAD nor DM on long-term clinical effects is reported widely, but the prognostic factors of non-DM patients presenting with chest pain without significant CAD are limited. A total of 1,046 patients with chest pain without DM and significant CAD who underwent coronary angiography (CAG) and acetylcholine (ACH) provocation tests were finally enrolled. Propensity score matching and multivariate Cox-proportional hazard ratio analysis were performed to adjust for baseline potential confounders. Major adverse cardiac and cerebrovascular events (MACCE) were defined as the composite of total death, myocardial infarction (MI), revascularization, stroke, and recurrent angina. This study aimed to evaluate the long-term prognostic factors for MACCE in patients with chest pain without DM and CAD up to 5 years. Coronary artery spasm (CAS) was the most common cause of chest pain. However, long-term MACCE of CAS was not worse than those of patients with chest pain without CAS when patients with CAS had subsequent optimal antianginal medication therapy. However, a recurrent chest pain remains a problem even with continuous antianginal medication therapy. Up to 5 years, the incidence of MACCE was in 7.3%, including recurrent angina 6.9%. Dyslipidemia (HR: 2.010, 95% CI 1.166-3.466, P = 0.012), mild-moderate (30-70%) coronary stenosis (HR: 2.369, 95% CI 1.118-5.018, P = 0.024), the use of aspirin (HR: 2.885, 95% CI 1.588-5.238, P < 0.001), and the use of nitrates (HR: 1.938, 95% CI 1.094-3.433, P = 0.023) were independent risk factors for MACCE. Among the patients with chest pain without DM and significant CAD, the incidence of MACE were rare, but recurrent angina was still a challenging problem who had treated with antianginal medications.

Vasospastic angina: a review on diagnostic approach and management.

Vasospastic angina (VSA) refers to chest pain experienced as a consequence of myocardial ischaemia caused by epicardial coronary spasm, a sudden narrowing of the vessels responsible for an inadequate supply of blood and oxygen. Coronary artery spasm is a heterogeneous phenomenon that can occur in patients with non-obstructive coronary arteries and obstructive coronary artery disease, with transient spasm causing chest pain and persistent spasm potentially leading to acute myocardial infarction (MI). VSA was originally described as Prinzmetal angina or variant angina, classically presenting at rest, unlike most cases of angina (though in some patients, vasospasm may be triggered by exertion, emotional, mental or physical stress), and associated with transient electrocardiographic changes (transient ST-segment elevation, depression and/or T-wave changes). Ischaemia with non-obstructive coronary arteries (INOCA) is not a benign condition, as patients are at elevated risk of cardiovascular events including acute coronary syndrome, hospitalization due to heart failure, stroke and repeat cardiovascular procedures. INOCA patients also experience impaired quality of life and associated increased healthcare costs. VSA, an endotype of INOCA, is associated with major adverse events, including sudden cardiac death, acute MI and syncope, necessitating the study of the most effective treatment options currently available. The present literature review aims to summarize current data relating to the diagnosis and management of VSA and provide details on the sequence that treatment should follow.

Diagnosis and treatment of epicardial coronary artery spasmVasospastic angina (VSA) refers to chest pain experienced as a consequence of a sudden narrowing of the epicardial coronary arteries. VSA can occur in patients with non-obstructive coronary arteries and obstructive coronary artery disease, with transient spasm causing chest pain and persistent spasm potentially leading to acute myocardial infarction. Reduced blood and oxygen supply in patients with non-obstructive coronary arteries is not a benign condition, as patients are at elevated risk of adverse cardiovascular events. These patients also experience impaired quality of life and associated increased healthcare costs. This review aims to summarise current data relating to the diagnosis of VSA and provides details on treatment strategies.

Association of the interleukine-6 polymorphism with catheter-induced coronary artery spasm in Egyptians.

BACKGROUND: The role of coronary artery spasm (CAS) was extended beyond variant angina to ischemic heart disease in general, including effort angina, unstable angina, acute myocardial infarction (MI) and sudden death. It is difficult and cumbersome to examine CAS during coronary angiography. Risk factors for CAS include smoking and genetic polymorphisms. AIM: We aimed to investigate the association of the interleukin-6 (IL-6) polymorphism with catheter-induced CAS in Egyptian patients who undergo coronary angiography. METHODS: This is a case-control study. Two hundred patients with chronic coronary artery disease who underwent elective coronary angiography were included in the study. Patients were divided into two groups: the non-CAS group (100 patients) and the CAS group (100 patients). The subjects were genotyped to the -572 C>G (rs 1800796) polymorphism of the IL-6 gene by PCR-restriction fragment length polymorphism. RESULTS: We found that patients with CAS have more risk factors for atherosclerosis compared to those without CAS. Smoking, the IL-6 GG genotype, and the G allele were independent risk factors for CAS. CONCLUSION: We concluded that the GG genotype and G allele of the IL-6 gene are associated with CAS. Smoking, the GG genotype, and the G allele of the IL-6 gene are independent predictors of catheter-induced CAS.

Safety and potential usefulness of sequential intracoronary acetylcholine and ergonovine administration for spasm provocation testing.

BACKGROUND: Although guidelines recommend intracoronary acetylcholine (ACh) and ergonovine (ER) provocation testing for diagnosis of vasospastic angina, the feasibility and safety of sequential (combined) use of both pharmacological agents during the same catheterization session remain unclear. OBJECTIVES: In this study, we investigated the feasibility and safety of sequential intracoronary ACh and ER administration for coronary spasm provocation testing. METHODS: The study included 235 patients who showed positive results on ACh and ER provocation testing. Initial intracoronary ACh administration was followed by ER administration for left coronary artery (LCA) spasm provocation testing. Subsequently, the right coronary artery (RCA) was subjected to sequential ACh and ER administration for provocation testing. The primary outcome of the study was the safety of sequential intracoronary ACh and ER provocation testing, which was assessed based on a composite of all-cause death, sustained ventricular tachycardia and fibrillation, and cardiogenic shock. RESULTS: Even in patients with negative results on sequential intracoronary ACh and ER provocation testing in the LCA and only ACh administration into the RCA, additional administration of ER into the RCA showed a positive provocation test result in 33 of 235 (14.0%) patients; three (1.3%) patients developed adverse effects (cardiogenic shock occurred in all cases) during LCA provocation testing. We observed no deaths attributable to spasm provocation testing. CONCLUSION: Sequential administration of intracoronary ACh and ER was associated with a relatively low major complication rate and may be safe and potentially useful for diagnosis of vasospastic angina.

Safety and potential usefulness of novel coronary spasm provocation testing protocolCoronary spasm represents a subtype of ischemic heart disease, potentially leading to heart attack. Although guidelines recommend intracoronary administration of different pharmacological agents, acetylcholine (ACh) and ergonovine (ER), for coronary spasm provocation testing, the feasibility and safety of sequential (combined) use of both drugs are unclear. In the present study, we showed that sequential administration of intracoronary ACh and ER was associated with a relatively low major complication rate and may be safe and potentially useful for diagnosis of coronary vasospasm.

Sudden diffuse spasm of multiple coronary arteries: A case report.

RATIONALE: Diffuse multivessel coronary artery spasm (DMV-CAS) was defined as a severe and reversible diffuse spasm occurring in more than 2 major coronary arteries, which is rare in clinical practice. Due to a wide lesion scope, DMV-CAS often occurs in the form of complications. It is not easy to be clinically diagnosed because it is too brief to be caught. Here, we report a rare case of spontaneous subtotal occlusion of 3 major coronary arteries induced by Vasalva action, which was confirmed in real-time by CAG. PATIENT CONCERNS: A 68-year-old man had sudden chest pain after forced defecation during hospitalization. The electrocardiogram showed transient ST segment elevation of the inferior wall lead, inversion of the anterior wall, and lateral wall leads T waves. Emergency CAG revealed elongated vessel beds in 3 coronary arteries and multiple diffuse stenosis, but none of the coronary arteries were completely occlusive. DIAGNOSES: Diagnoses of DMV-CAS were made based on CAG findings and postmedication response. INTERVENTIONS: Nitroglycerin was administered in the coronary arteries. The anti-vasospasm, antiplatelet aggregation and lipid-regulating drugs were administered orally. OUTCOMES: The patient was discharged on the 7th day with complete resolution of symptoms and normalization of the electrocardiography findings. No ischemic events occurred during a follow-up for 5 months. LESSONS: This case highlights the identification of multivessel diffuse coronary spasm and acute myocardial infarction, and the prevention of CAS triggers, which requires the attention of clinicians.

Comparison of clinical outcomes in patients with mixed angina and pure vasospastic angina.

OBJECTIVE: This study investigated differences in clinical outcomes between mixed angina (MA) and pure vasospastic angina (PVA). METHODS: A total of 524 vasospastic angina patients who did or did not have >50% coronary artery stenosis from January 2005 to January 2021 were divided into two groups (Group 1: PVA, N  = 399; Group 2: MA, N  = 125) and then three groups [Group 1: PVA, N  = 399; Group 2: MA without percutaneous coronary intervention (PCI), N  = 67; Group 3: MA with PCI, N  = 58] for assessment. We recorded the incidence of major adverse cardiac and cerebrovascular events (MACCE: the composite of death, myocardial infarction, nonfatal stroke or rehospitalization) during 3-year clinical follow-up. RESULTS: Compared to the PVA group, there were significant differences in MACCE (20.8% vs. 11.8%, P  = 0.011) and rehospitalization (20.0% vs. 9.8%, P  = 0.002) in the MA group. Kaplan-Meier analysis showed that patients in the MA with PCI group had the highest cumulative incidence rate of MACCE during the 3-year follow-up (log-rank P  < 0.001). CONCLUSION: Compared with the PVA patients, MA patients had significantly worse clinical outcomes during long-term follow-up.

Coronary spasm and vasomotor dysfunction as a cause of MINOCA.

Increasing evidence has shown that coronary spasm and vasomotor dysfunction may be the underlying cause in more than half of myocardial infarctions with non-obstructive coronary arteries (MINOCA) as well as an important cause of chronic chest pain in the outpatient setting. We review the contemporary understanding of coronary spasm and related vasomotor dysfunction of the coronary arteries, the pathophysiology and prognosis, and current and emerging approaches to diagnosis and evidence-based treatment.

Atherosclerosis Vindicated: A Case of Chest Pain Due to Capecitabine-Induced Coronary Artery Spasm.

BACKGROUND Capecitabine and other 5-fluorouracil prodrugs are medications widely employed in treating solid tumors, including breast and colorectal cancer. However, they carry a notable risk for cardiotoxicity, including coronary vasospasm, possibly related to their impact on vascular endothelium and smooth muscle. CASE REPORT We present a case of a 45-year-old male with a pancreatic neuroendocrine tumor who developed exertional chest pain after starting capecitabine. Initial evaluations in the emergency department, including a 12-lead electrocardiogram and cardiac enzymes, were normal, but suspicion for coronary vasospasm persisted due to the temporal relationship with drug initiation and symptom characteristics. A graded exercise test reproduced his symptoms, accompanied by hyperacute peaked T waves and subsequent ST segment elevations in the inferior leads. Coronary angiography revealed patent coronary arteries, rendering provocative testing unnecessary due to a high clinical suspicion of capecitabine-induced vasospasm. Discontinuing the patient's medication was a more efficient approach than continuing additional cardiac workup while the drug was still administered. After multidisciplinary discussion, capecitabine was discontinued, leading to symptom resolution and a negative repeat graded exercise test. CONCLUSIONS This case underscores the potential for capecitabine to induce coronary artery vasospasm, emphasizing the importance of prompt medication cessation. Patients receiving capecitabine therapy and experiencing chest pain should undergo an evaluation with consideration of capecitabine-induced vasospasm in the differential diagnosis. Prompt recognition and medication cessation are critical to prevent serious cardiovascular complications including death. In our patient, discontinuing capecitabine resolved his symptoms, emphasizing the significance of discontinuing the causative drug and seeking alternative chemotherapy regimens.

Coronary Artery Spasm During Pulsed Field vs Radiofrequency Catheter Ablation of the Mitral Isthmus.

Importance: In treating atrial fibrillation, pulsed field ablation (PFA) is a novel energy modality with comparable efficacy to conventional thermal ablation, such as radiofrequency ablation (RFA), but with the benefit of some preferentiality to myocardial tissue ablation. Studies have demonstrated important safety advantages, including the absence of esophageal injury or pulmonary vein stenosis and only rare phrenic nerve injury. However, there is emerging evidence of coronary artery vasospasm provoked by PFA. Objective: To compare the incidence and severity of left circumflex arterial vasospasm between PFA and RFA during adjacent ablation along the mitral isthmus. Design, Setting, and Participants: This prospective cohort study enrolled consecutive adult patients receiving first-ever PFA or RFA of the mitral isthmus during catheter ablation of atrial fibrillation in 2022 with acute follow-up at a single referral European center. Exposure: A posterolateral mitral isthmus line was created using either a multielectrode pentaspline PFA catheter (endocardial ablation) or a saline-irrigated RFA catheter. Simultaneous diagnostic coronary angiography was performed before, during, and after catheter ablation. Nitroglycerin was planned for spasm persisting beyond 20 minutes or for significant electrocardiographic changes. Main Outcomes and Measures: The frequency and severity of left circumflex arterial vasospasm was assessed and monitored, as were time to remission and any need for nitroglycerin administration. Results: Of 26 included patients, 19 (73%) were male, and the mean (SD) age was 65.5 (9.3) years. Patients underwent either PFA (n = 17) or RFA (n = 9) along the mitral isthmus. Coronary spasm was observed in 7 of 17 patients (41.2%) undergoing PFA: in 7 of 9 (77.8%) when the mitral isthmus ablation line was situated superiorly and in 0 of 8 when situated inferiorly. Conversely, coronary spasm did not occur in any of the 9 patients undergoing RFA. Of 5 patients in whom crossover PFA was performed after RFA failed to achieve conduction block, coronary spasm occurred in 3 (60%). Most instances of spasm (9 of 10 [90%]) were subclinical, with 2 (20%) requiring nitroglycerin administration. The median (range) time to resolution of spasm was 5 (5-25) minutes. Conclusion and Relevance: When creating a mitral isthmus ablation line during catheter ablation of atrial fibrillation, adjacent left circumflex arterial vasospasm frequently occurred with PFA and not RFA but was typically subclinical.

Endoscopic Thoracic Sympathectomy in the Treatment of Vasospastic Angina Resistant to Medical Therapy.

BACKGROUND: In this study, we aimed to investigate the clinical follow-up results of endoscopic thoracic sympathectomy (ETS) in the treatment of vasospastic angina (VSA) resistant to maximal medical therapy. METHODS: A total of 80 patients with VSA who presented to our hospital between 2010 and 2022 were included in our study. Among them, 6 patients who did not respond to medical therapy underwent ETS. In-hospital and long-term clinical outcomes of patients who underwent ETS were recorded. RESULTS: The median age of the patients with VSA was 57 [48-66] years, and 70% of the group were males. In the ETS group, compared to the non-ETS group, higher numbers of hospital admissions and coronary angiographies were observed before ETS (median 6 [5-6] versus 2 [1-3], P <.001; median 5 [3-6] versus 2 [1-3], P =.004, respectively). Additionally, while 2 patients (33.3%) in the ETS group had implantable cardioverter defib-rillator (ICD), only 2 patients (2.7%) in the non-ETS group had ICD (P =.027). Out of the 6 patients who underwent ETS, 2 were females, with a median age of 56 [45-63] years. Four patients underwent successful bilateral ETS, while 2 patients underwent unilateral ETS. During the follow-up period after ETS, only 3 patients experienced sporadic attacks (once in 28 months, twice in 41 months, and once in 9 years, respectively), while no attacks were observed in 3 patients during their median follow-up of 7 years. CONCLUSION: It appears that ETS is effective in preventing VSA attacks without any major complications.