Sympathectomy as a treatment for refractory coronary artery spasm

Innervation of the coronary arteries and its role in controlling microvascular resistance

The coronary circulation plays a crucial role in balancing myocardial perfusion and oxygen demand to prevent myocardial ischemia. Extravascular compressive forces, coronary perfusion pressure, and microvascular resistance are involved to regulate coronary blood flow throughout the cardiac cycle. Autoregulation of the coronary blood flow through dynamic adjustment of microvascular resistance is maintained by complex interactions among mechanical, endothelial, metabolic, neural, and hormonal mechanisms. This review focuses on the neural mechanism. Anatomy and physiology of the coronary arterial innervation have been extensively investigated using animal models. However, findings in the animal heart have limited applicability to the human heart as cardiac innervation is generally highly variable among species. So far, limited data are available on the human coronary artery innervation, rendering multiple questions unresolved. Recently, the clinical entity of ischemia with non-obstructive coronary arteries has been proposed, characterized by microvascular dysfunction involving abnormal vasoconstriction and impaired vasodilation. Thus, measurement of microvascular resistance has become a standard diagnostic for patients without significant stenosis in the epicardial coronary arteries. Neural mechanism is likely to play a pivotal role, supported by the efficacy of cardiac sympathetic denervation to control symptoms in patients with angina. Therefore, understanding the coronary artery innervation and control of microvascular resistance of the human heart is increasingly important for cardiologists for diagnosis and to select appropriate therapeutic options. Advancement in this field can lead to innovations in diagnostic and therapeutic approaches for coronary artery diseases.

Refractory coronary vasospasm complicated by complete atrio-ventricular block during neck surgery: is there an indication for pacing?

Vasospastic angina is a clinical condition characterized by coronary artery spasm in angiographically normal coronary arteries. Vasospastic angina can often lead to ventricular arrhythmias, sudden cardiac death, or life-threatening bradyarrhythmias, such as high-degree atrioventricular block or asystole. We present the unusual case of a woman with depressive syndrome who underwent emergency surgery for hemostasis of a neck lesion that caused hemorrhagic shock after a suicide attempt. During surgery, the electrocardiogram revealed inferior and posterior ST-segment elevation, total atrioventricular block and torsades de pointes; the patient also suffered 4 minutes of cardiac arrest. A temporary pacemaker was placed. Coronary angiography showed right coronary artery vasospasm. Following a second similar episode after tracheostomy, a permanent pacemaker was implanted. The indication for definitive electrostimulation in such a context and the stimulation mechanisms of the carotid sinus underlying vasospasm constitute the interesting points of this clinical case. LEARNING OBJECTIVE: The indication for definitive electrostimulation in a context of recurrent episodes of high-degree atrioventricular block during vasospastic angina and the stimulation mechanisms of the carotid sinus underlying vasospasm constitute the interesting points of this clinical case.

Management of Coronary Artery Spasm

Calcium channel blockers (CCBs) are the first-line treatment for coronary artery spasm (CAS). When CAS-related angina symptoms are not well controlled by CCB therapy, long-acting nitrates or (where available) nicorandil can be added as second-line medications. In the case of CAS refractory to standard treatments, several other alternative drugs and interventions have been proposed, including the Rho-kinase inhibitor fasudil, anti-adrenergic drugs, neural therapies and percutaneous coronary interventions. In patients with syncope or cardiac arrest caused by CAS-related tachyarrhythmias, or even bradyarrhythmias, implantation of an ICD or pacemaker, respectively, should be considered according to the risk of recurrence and efficacy of vasodilator therapy.

Sympathectomy versus conventional treatment for refractory coronary artery spasm

BACKGROUND

There is no clear consensus on the potential efficacy and indications for sympathectomy to prevent recurrence of vasospasm in patients with refractory coronary artery spasm (CAS).

OBJECTIVE

To compare the clinical outcomes of sympathectomy with those of conventional treatment in patients with refractory CAS.

PATIENTS AND METHODS

Patients with refractory CAS were randomly assigned to sympathectomy group (n = 37) or conventional treatment group (n = 42). The primary end point was a composite of major adverse cardiac event (MACE) episodes (including cardiac death, nonfatal myocardial infarction, unstable angina, heart failure, and life-threatening arrhythmia), and the secondary end point was death from any cause within 24 months after randomization.

RESULTS

During the follow-up period of 24 months, the incidence of MACE in the sympathectomy and conventional treatment groups was 16.22 and 61.90%, respectively (P = 0.0001). All-cause death as the secondary end point occurred in zero and six (14.29%) patients, respectively (P = 0.0272). The Kaplan-Meier curve for MACE and all-cause death showed a significant between-group difference (log-rank test, P = 0.0013 and 0.0176, respectively).

CONCLUSION

Compared with conventional treatment, sympathectomy significantly reduced the composite end point of MACE episodes and death from any cause in patients with refractory CAS by effectively preventing recurrence of vasospasm.

Intractable coronary fibromuscular dysplasia leading to end-stage heart failure and fatal heart transplantation

Coronary fibromuscular dysplasia is uncommon, and even rarer its unstable and recurrent course. We present the unique case of a 52‐year‐old woman who underwent in total 12 coronary angiographies and three percutaneous coronary intervention within 24 months because of repetitive acute coronary syndromes due to refractory spasm, dissection, restenosis all leading to end‐stage heart failure, and heart transplantation. The patient died 12 days after the heart transplantation complicated by intraoperative acute thrombotic occlusion of left anterior descending artery of the graft despite normal pretransplant coronary angiography. Autopsy of the recipient heart confirmed coronary fibromuscular dysplasia with massive intimal hyperplasia and restenosis.

[Prinzmetal angina. Questions of pathogenesis, clinic, diagnosis and treatment]

Current problems of Prinzmetal angina (vasospastic angina, variant angina) considers in this review. Attention is drawn to early diagnosis, which should be comprehensive, taking into account possible atypical courses and the development of complications. The important role of electrocardiographic monitoring (including using implantable recorders) is highlighted. It is emphasized that patients with cardiac arrhythmias, syncope are at high risk of developing sudden cardiac death. In this category of patients, it is recommended to timely determine the indications for implantation of a cardioverter - defibrillator. Authors consider the prospects of using new methods of treatment of angina pectoris.

Refractory Vasospastic Angina: When Typical Medications Don't Work

Vasospastic angina (VSA) is defined as spasm of the coronaries leading to transient constriction and eventual myocardial ischemia. VSA is treated typically with calcium-channel blockers (CCBs) and nitrates. However, there are times when the vasospasm is refractory to typical medications. When this occurs, unconventional treatment modalities may be employed for symptomatic relief. We present a case of a 48-year-old-male with a history of inferior ST-elevation myocardial infarction (STEMI) status post percutaneous coronary intervention (PCI) with drug-eluting stent (DES) to the distal right coronary artery (RCA), who presented with recurrent angina. The pain was described as pressure-like, substernal, radiating to both arms, and similar to his previous STEMI presentation. On presentation to the emergency room, he had an elevated serum troponin with no electrocardiogram (EKG) changes. He was taken to the cath lab where it was found that he revealed severe focal stenosis just proximal to the previously placed stent. Immediately after guidewire passage into the RCA, acute vasospasm developed, resulting in diffuse, severe stenosis, extending over previously normal segments to the proximal RCA, resolving with intracoronary nicardipine and nitroglycerin, including the initial focal stenosis. The patient was diagnosed with VSA. Unfortunately, despite optimal medical therapy, he developed refractory VSA, requiring the use of unconventional treatment methods. Our patient presented with a lesser-known phenomenon called refractory VSA, where intermittent vasospasm continues despite being on a combination of two medications. Treatment for VSA is well-documented, however, little data is available for refractory VSA.

Near-infrared Intraoperative Imaging of Thoracic Sympathetic Nerves: From Preclinical Study to Clinical Trial

The sympathetic nervous system controls and regulates the activities of the heart and other organs. Sympathetic nervous system dysfunction leads to disease. Therefore, intraoperative real-time imaging of thoracic sympathetic nerves (ITSN) would be of great clinical significance for diagnosis and therapy. The aim of this experimental study was to evaluate the feasibility and validity of intraoperative ITSN using indocyanine green (ICG).

METHODS

ITSN using ICG was performed on 10 rabbits to determine its feasibility. Animals were allocated to two groups. The rabbits in one group received the same dose of ICG, but were observed at different times. The rabbits in the other group were administered different doses of ICG, but were observed at the same time. Signal to background ratio (SBR) was measured in regions of interest in all rabbits. Furthermore, fifteen consecutive patients with pulmonary nodules were intravenously injected with ICG 24 h preoperatively and underwent near-infrared (NIR) fluorescence imaging (FI) thoracoscopic surgeries between July 2015 and June 2016. A novel self-developed NIR and white-light dual-channel thoracoscope system was used. SBRs of thoracic sympathetic nerves were calculated in all patients.

RESULTS

In the preclinical study, we were able to precisely recognize each rabbit's second (T2) to fifth (T5) thoracic ganglia on both sides of the spine using ITSN with ICG. In addition, we explored the relationship between SBR and the injection time of ICG and that between SBR and the dose of ICG. Using the novel dual-channel thoracoscope system, we were able to locate the ganglia from the stellate ganglion (SG) to the sixth thoracic ganglion (T6), as well as the chains between these ganglia in all patients with a high SBR value of 3.26 (standard deviation: 0.57). The pathological results confirmed our findings.

CONCLUSION

We were able to use ICG FI to distinguish thoracic sympathetic nerves during NIR thoracoscopic surgery. The technique may replace the rib-oriented method as standard practice for mapping the thoracic sympathetic nerves.

Acute Coronary Syndromes: The Way Forward From Mechanisms to Precision Treatment

Well into the 21st century, we still triage acute myocardial infarction on the basis of the presence or absence of ST-segment elevation, a century-old technology. Meanwhile, we have learned a great deal about the pathophysiology and mechanisms of acute coronary syndromes (ACS) at the clinical, pathological, cellular, and molecular levels. Contemporary imaging studies have shed new light on the mechanisms of ACS. This review discusses these advances and their implications for clinical management of the ACS for the future. Plaque rupture has dominated our thinking about ACS pathophysiology for decades. However, current evidence suggests that a sole focus on plaque rupture vastly oversimplifies this complex collection of diseases and obscures other mechanisms that may mandate different management strategies. We propose segmenting coronary artery thrombosis caused by plaque rupture into cases with or without signs of concomitant inflammation. This distinction may have substantial therapeutic implications as direct anti-inflammatory interventions for atherosclerosis emerge. Coronary artery thrombosis caused by plaque erosion may be on the rise in an era of intense lipid lowering. Identification of patients with of ACS resulting from erosion may permit a less invasive approach to management than the current standard of care. We also now recognize ACS that occur without apparent epicardial coronary artery thrombus or stenosis. Such events may arise from spasm, microvascular disease, or other pathways. Emerging management strategies may likewise apply selectively to this category of ACS. We advocate this more mechanistic approach to the categorization of ACS to provide a framework for future tailoring, triage, and therapy for patients in a more personalized and precise manner.

Thoracic Sympathectomy for Severe Refractory Multivessel Coronary Artery Spasm

Coronary artery spasm is a rare but potentially fatal disease. Herein, we report a case of recurrent ST-segment myocardial infarctions and ventricular fibrillation complicating severe multivessel coronary artery spasm successfully treated with bilateral thoracic surgical sympathectomy.

Thoracic sympathectomy: a review of current indications

BACKGROUND

Thoracic sympathetic ablation was introduced over a century ago. While some of the early indications have become obsolete, new ones have emerged. Sympathetic ablation is being still performed for some odd indications thus prompting the present study, which reviews the evidence base for current practice.

METHODS

The literature was reviewed using the PubMed/Medline Database, and pertinent articles regarding the indications for thoracic sympathectomy were retrieved and evaluated. Old, historical articles were also reviewed as required.

RESULTS AND CONCLUSIONS

Currently, thoracic sympathetic ablation is indicated mainly for primary hyperhidrosis, especially affecting the palm, and to a lesser degree, axilla and face, and for facial blushing. Despite modern pharmaceutical, endovascular and surgical treatments, sympathetic ablation has still a place in the treatment of very selected cases of angina, arrhythmias and cardiomyopathy. Thoracic sympathetic ablation is indicated in several painful conditions: the early stages of complex regional pain syndrome, erythromelalgia, and some pancreatic and other painful abdominal pathologies. Although ischaemia was historically the major indication for sympathetic ablation, its use has declined to a few selected cases of thromboangiitis obliterans (Buerger's disease), microemboli, primary Raynaud's phenomenon and Raynaud's phenomenon secondary to collagen diseases, paraneoplastic syndrome, frostbite and vibration syndrome. Thoracic sympathetic ablation for hypertension is obsolete, and direct endovascular renal sympathectomy still requires adequate clinical trials. There are rare publications of sympathetic ablation for primary phobias, but there is no scientific basis to support sympathetic surgery for any psychiatric indication.

Successful treatment using corticosteroids in a patient with refractory vasospastic angina and bronchial asthma

We report a 55-year-old female patient with refractory vasospastic angina and bronchial asthma treated successfully with corticosteroids. She was diagnosed with vasospastic angina by coronary angiography and the acetylcholine provocation test. Even after administration of oral vasodilators (benidipine, diltiazem, nicorandil, isosorbide mononitrate) she had recurrent chest pain with ST elevation. She had a history of bronchial asthma, so we added 30 mg/day of oral prednisolone. Her symptoms disappeared completely upon treatment. This case report suggests that corticosteroids are a therapeutic choice for patients with refractory vasospastic angina, especially for those with bronchial asthma. <Learning objective: We report a 55-year-old female patient with refractory vasospastic angina and bronchial asthma. Even after administration of oral vasodilators, she had recurrent chest pain with ST elevation. She had a history of bronchial asthma, so we added 30 mg/day of oral prednisolone. Her symptoms disappeared completely upon treatment. This case report suggests that corticosteroids are a therapeutic choice for patients with refractory vasospastic angina, especially for those with bronchial asthma.>.