Acute thrombosis of the sinus node artery: arrhythmological implications

Sino-atrial nodal artery occlusion causing acute sinus node dysfunction after percutaneous coronary intervention: Case report and systematic review

BACKGROUND

New antithrombotic medications and improved stent designs have reduced branch occlusion, although the sino-atrial nodal artery (SANA) may still be occluded after a percutaneous coronary intervention (PCI), causing sinus node dysfunction (SND). Ischemic sinus nodes are usually asymptomatic but can cause sinus arrest sometimes requiring pacemaker placement. In rare cases, junctional escape rhythms, a manifestation of sinus exit blocks after PCI, can predict cardiogenic shock.

METHODS

We present a case study of a patient who underwent bifurcation PCI to the LMCA to the LCX but subsequently developed cardiogenic shock as a result of SND, a junctional escape rhythm required substantial inotropic support. This case offers an exemplification of a sparsely documented, yet infrequent manifestation of iatrogenic ischemic SND at an unorthodox site, the confluence of the LMCA-LCX. In addition, we conducted a comprehensive analysis of 22 scholarly works pertaining to the subject of sinus node dysfunction (SND) subsequent to PCI resulting from ischemia caused by stenosis or occlusion of the SANA.

RESULTS

RCA was responsible for 96.1% of SND cases, whereas LCX was responsible for 3.9%. SND was asymptomatic in 49.3% of cases and junctional escape rhythm in 37.6% of symptomatic cases. 28% needed a temporary transvenous pacemaker, while 7.8% needed a permanent one. Interventional management recanalized the SANA in 5.2% of patients, restoring flow.

CONCLUSION

Transient sino-atrial node ischemia after PCI can cause acute SND. Before stent implantation, doctors should consider SND. Complete plaque evaluation around the SANA is needed before choosing the best PCI procedure.

Uncommon Culprit Vessel of de Winter Electrocardiogram Pattern

This case report describes a patient in their 50s who presented to the emergency department with perspiration, persistent and squeezing chest pain, and chest distress that had persisted for 90 minutes without relief.

A case of atrial septal defect associated with anomalous sinoatrial node artery in pulmonary atresia with intact ventricular septum

An 11‐year‐old boy affected by pulmonary atresia with intact ventricular septum (AP‐IVS) was listed for percutaneous pulmonary valvuloplasty and closure of multi‐fenestrated atrial septal defect (ASD). Intra‐procedural transesophageal echocardiography arose the suspect of abnormal coronary artery pattern while selective angiography documented a single sinoatrial node artery (SANa) with an unusual retro‐aortic course. As consequence, we proceeded to effectively close the defects with a not self‐centering device placed in the most central side hole. This case supports the hypothesis that sometimes arrhythmic complication during ASD closure procedures might be due to unrecognized injury of the SANa.

ECG analysis in patients with acute coronary syndrome undergoing invasive management: rationale and design of the electrocardiography sub-study of the MATRIX trial

BACKGROUND

The twelve‑lead electrocardiogram (ECG) has become an essential tool for the diagnosis, risk stratification, and management of patients with acute coronary syndromes (ACS). However, several areas of residual controversies or gaps in evidence exist. Among them, P-wave abnormalities identifying atrial ischemia/infarction are largely neglected in clinical practice, and their diagnostic and prognostic implications remain elusive; the value of ECG to identify the culprit lesion has been investigated, but validated criteria indicating the presence of coronary occlusion in patients without ST-elevation are lacking; finally, which criteria among the multiple proposed, better define pathological Q-waves or success of revascularisation deserve further investigations.

METHODS

The Minimizing Adverse hemorrhagic events via TRansradial access site and systemic Implementation of AngioX (MATRIX) trial was designed to test the impact of bleeding avoidance strategies on ischemic and bleeding outcomes across the whole spectrum of patients with ACS receiving invasive management. The ECG-MATRIX is a pre-specified sub-study of the MATRIX programme which aims at analyzing the clinical value of ECG metrics in 4516 ACS patients (with and without ST-segment elevation in 2212 and 2304 cases, respectively) with matched pre and post-treatment ECGs.

CONCLUSIONS

This study represents a unique opportunity to further investigate the role of ECGs in the diagnosis and risk stratification of ACS patients with or without ST-segment deviation, as well as to assess whether the radial approach and bivalirudin may affect post-treatment ECG metrics and patterns in a large contemporary ACS population.

Transient sinus arrest due to sinus node artery thrombus after revascularisation of the left circumflex artery

We present a case of sinus arrest and junctional escape rhythm from sinus node artery (SNA) thrombus in a 55-year-old man after revascularisation of right coronary and proximal circumflex arteries for infero-posterior wall ST-segement elevation myocardial infarction (STEMI). Sinus arrest from occlusion of the SNA is uncommon. The ensuing bradycardia may have haemodynamic consequences requiring temporary pacing but is almost always self-limited.

Atrial fibrillation, an epiphenomenon of acute Stanford type-A aortic dissection with suspected intimo-intimal intussusception

Supraventricular arrhythmias can sometimes be "only" epiphenomena appearing during acute hypoxia, pneumonia, pulmonary embolism, and thrombosis. Indeed, atrial fibrillation is not rare in acute aortic dissection as it is estimated in about one half of patients and may be secondary to a perfusion deficit of the sinoatrial node artery.

Mechanism underlying impaired cardiac pacemaking rhythm during ischemia: A simulation study

Ischemia in the heart impairs function of the cardiac pacemaker, the sinoatrial node (SAN). However, the ionic mechanisms underlying the ischemia-induced dysfunction of the SAN remain elusive. In order to investigate the ionic mechanisms by which ischemia causes SAN dysfunction, action potential models of rabbit SAN and atrial cells were modified to incorporate extant experimental data of ischemia-induced changes to membrane ion channels and intracellular ion homeostasis. The cell models were incorporated into an anatomically detailed 2D model of the intact SAN-atrium. Using the multi-scale models, the functional impact of ischemia-induced electrical alterations on cardiac pacemaking action potentials (APs) and their conduction was investigated. The effects of vagal tone activity on the regulation of cardiac pacemaker activity in control and ischemic conditions were also investigated. The simulation results showed that at the cellular level ischemia slowed the SAN pacemaking rate, which was mainly attributable to the altered Na+-Ca2+ exchange current and the ATP-sensitive potassium current. In the 2D SAN-atrium tissue model, ischemia slowed down both the pacemaking rate and the conduction velocity of APs into the surrounding atrial tissue. Simulated vagal nerve activity, including the actions of acetylcholine in the model, amplified the effects of ischemia, leading to possible SAN arrest and/or conduction exit block, which are major features of the sick sinus syndrome. In conclusion, this study provides novel insights into understanding the mechanisms by which ischemia alters SAN function, identifying specific conductances as contributors to bradycardia and conduction block.

Proximal complete occlusion of right coronary artery presenting with precordial ST-segment elevation: A case report

BACKGROUND

It is well known that cardiologists empirically judge the culprit lesion of acute ST-segment elevation myocardial infarction (STEMI) according to the corresponding electrocardiographic leads. However, In addition to the obstruction of left anterior descending (LAD) coronary artery, rare cases with the occlusion of proximal right coronary artery (RCA) and/or isolated right ventricular (RV) branch showed the ST-segment elevation in precordial leads V1-V3 as well.

CASE SUMMARY

We reported a patient complaining of acute chest pain and suffering ventricular fibrillation (VF) on admission. The electrocardiogram (ECG) showed mild ST-segment elevation in precordial leads V1-V3 and V4R. Bedside echocardiography displayed normal left ventricular ejection fraction and slight RV dilation. Proximal occlusion of nondominant RCA was confirmed by coronary angiography and urgent percutaneous coronary intervention (PCI) to RCA successfully resolved the chest pain and ST-segment elevation.

CONCLUSION

Undoubtedly, coronary angiography is usually the definite measurement for the diagnosis of culprit lesion. However, bedside echocardiography, ST-segment features in left and right precordial leads, and heart rate will be the additional information for judging ST-segment elevation in precordial leads V1-V3 resulting from occlusion of RCA or LAD.

Biology of the Sinus Node and its Disease

The sinoatrial node (SAN) is the normal pacemaker of the heart and SAN dysfunction (SND) is common, but until recently the pathophysiology was incompletely understood. It was usually attributed to idiopathic age-related fibrosis and cell atrophy or ischaemia. It is now evident that changes in the electrophysiology of the SAN, known as electrical remodelling, is an important process that has been demonstrated in SND associated with heart failure, ageing, diabetes, atrial fibrillation and endurance exercise. Furthermore, familial SND has been identified and mutations have been characterised in key pacemaker genes of the SAN. This review summarises the current evidence regarding SAN function and the pathophysiology of SND.

Sinus dysfunction after stent implantation in the right coronary artery immediately recovered after reflow in the sinus node artery

A 67-year-old man who had a history of syncope was admitted because of effort angina. The sinus node (SN) was the single blood supply from the right coronary artery (RCA). After we implanted 2 everolimus-eluting stents for RCA, slow-flow occurred and the SN artery was occluded, and junctional escape rhythm was sustained. After the wiring to the occluded SN artery, junctional escape rhythm immediately recovered to sinus rhythm, and the patient achieved continuous sinus rhythm and stable hemodynamics. Given that acute SN ischemia is a possible cause of sinus dysfunction, careful choice of a percutaneous coronary intervention strategy should be taken into consideration if the SN artery is the single blood supply from the RCA and if syncopal history is present.

Atrial coronary artery occlusion during elective percutaneous coronary angioplasty

BACKGROUND

Atrial arteries arise from the right and left circumflex coronary arteries and they may be accidentally occluded during percutaneous coronary angioplasty; however, this complication is not well known. The aim of our study was to analyze the incidence and risk factors of accidental atrial branch occlusion (ABO) during elective angioplasty.

METHODS AND MATERIALS

Clinical records and coronary angiography of 200 patients undergoing elective angioplasty were retrospectively analyzed. Atrial branches were identified and in each vessel we measured the luminal diameter, flow grade, and the location of atherosclerotic plaques. Patients were allocated either into the ABO group if atrial branch flow fell from TIMI grades 2-3 to 0-1 after procedure or in the non-ABO group if TIMI flow was preserved.

RESULTS

Atrial branch occlusion occurred in 43 (21.5%) patients. The atrial branch diameter was larger in non-ABO than in ABO group (1.29mm, SD 0.33 versus 0.97mm, SD 0.22, p=<0.0001). Plaques at atrial branch origin were present in 93% of ABO group, only in 31.8% of non-ABO (p≤0.0001). Predictors of ABO were a cut-off vessel diameter of 1.00mm (ROC 77% sensitivity and 67.5% specificity, p≤0.0001), the presence of atherosclerotic plaque at the ostium of atrial branch and maximal inflation pressure during stenting.

CONCLUSIONS

The occurrence of ABO is frequent after elective angioplasty of right or circumflex coronary arteries in an experienced interventional center. Risk factors were the diameter and the presence of ostial plaques in the atrial branches, and the maximal inflation pressure during stenting.

A rare case of myocardial infarction related to diagnostic intravascular ultrasound

A 71-year-old man underwent intracoronary stent implantation for acute inferior myocardial infarction (MI). Immediately after diagnostic intravascular ultrasound (IVUS) at 8 months' follow-up, an acute occlusion of the sinus node (SN) artery appeared, which developed sinus arrest with junctional escape rhythm. The serum level of high-sensitivity troponin T (TpT) was markedly elevated on the day after the procedure (2.1-32.5 ng/l), which was indicative of MI related to IVUS. Under continuous intravenous infusion of unfractionated heparin, the escape rhythm changed to lower atrial rhythm on the 4th day, and recovered to sinus rhythm on the 14th day. Coronary angiography (CAG) on 15th day showed a recanalization of the SN artery, but optical coherence tomography identified that disrupted plaque and white thrombus still existed in the ostium of the SN artery. The patient was discharged on maintenance anticoagulation therapy. We hypothesized from this case that IVUS-related myocardial injury may exist without clinical problems. Our retrospective investigation showed that the median levels of high-sensitivity TpT in 20 patients who underwent CAG and subsequent diagnostic IVUS significantly increased from 0.6 (interquartile range 0.3-1.1) to 1.6 (0.7-3.6) ng/l (P < 0.05), suggesting that IVUS may induce very low levels of myocardial injury. In conclusion, we experienced a rare case of IVUS-related MI caused by an acute occlusion of the SN artery. This case reaffirms that we should pay more attention to manipulation of IVUS catheters.

Anatomy of the sinoatrial nodal branch in Korean population: imaging with MDCT

Objective

To evaluate, on a retrospective basis, the anatomic characteristics of the arterial supply to the sinoatrial node (SAN) in the Korean population using an ECG-gated multi-detector CT (MDCT).

Materials and Methods

The electrocardiographic-gated MDCTs of 500 patients (258 men and 242 women; age range, 17-83 years; mean age, 58.6 ± 12.04 years) were analyzed retrospectively. In each case, the SAN artery (arteries) was named according to a special nomenclature with regard to origin, course, and termination.

Results

A total of 516 SAN arteries were visualized in 496 patients. The SAN was supplied by a single artery in 476 (96.4%) cases and by 2 arteries in 18 (3.6%) cases. The SAN originated from the right coronary artery in 265 (53.4%) cases and from the left circumflex in 213 (43%) cases.

Conclusion

This study can provide basic data on variations of the SAN artery in the Korean population.

Sinus arrest following right coronary artery stent implantation

Sinus arrest rarely occurs during acute myocardial infarction involving the right coronary artery (RCA) and sinus node (SN) artery. We report a rare case of sinus arrest caused by SN artery occlusion following RCA stenting. A 56-year-old woman with a significant history of RCA stenosis with prior bare metal stenting, presented to the emergency department with anginal chest pain. Initial work up showed significant elevation of cardiac troponin T with T-wave inversion in the inferior leads on electrocardiogram (ECG). Coronary angiography revealed a 90% stenosis of midportion of the RCA, mild occlusion in the left anterior descending coronary and left circumflex coronary arteries. Stenting was performed on the RCA lesion. Immediately after undergoing those interventions, thrombosis developed and occluded SN artery. Electrocardiogram showed junctional escape rhythm without P waves at a heart rate of 30 beats per minute, suggesting sinus arrest. The clot in the SN artery was identified and thrombectomy was performed. Neither symptoms nor hypotension were identified during this arrhythmia. Six days later, normal sinus rhythm began to appear on EKG with improving heart rate, and patient still remained completely hemodynamically stable. Pre-discharge exercise stress test had shown 50% predicted heart rate without ST segment change. Sinus node dysfunction is commonly related to degenerative processes, and rarely caused by thrombosis in the SN artery. In our case, we emphasize the potential complication of sinus arrest after RCA stent implantation.

Subocclusion of the sinus node artery during coronary angioplasty: arrhythmological considerations

We report the case of a 58-year-old man who developed atrial fibrillation as a result of iatrogenic subocclusion of a diseased sinus node artery, originating from the left circumflex artery (LCx), occurring during LCx stenting, suggestive of an ischemic etiology of sinus node dysfunction.

Left atrial infarction: a case report and review of the literature

The majority of cardiac related deaths are due to ischemic heart disease, with the most common clinical scenario being severe coronary artery atherosclerosis resulting in left ventricular myocardial infarction. However, infarction of other cardiac chambers does occur, and often has specific clinical associations. We report a case of a 70-year-old man who suffered from left atrial infarction that resulted in a transmural rupture of his left atrium. The patient had a history of rheumatic heart disease, mitral valve stenosis, and severe atherosclerotic coronary artery disease. Four days before death, he underwent mitral valve replacement and left circumflex coronary artery bypass. Two days later, he developed atrial fibrillation. On the day of death, he had decreased mental status, questionable seizure activity, hematemesis, ventricular tachycardia, and eventually asystole. At autopsy, he had significant hemopericardium with a fibrinous pericarditis and bilateral hemothoraces (total blood volume: 1250 mL). A 0.1 to 0.2 cm left atrial transmural defect was identified. The prosthetic mitral valve was free of vegetations, and completely intact. Similarly, the left circumflex artery bypass graft was completely patent and unremarkable. Severe calcific atherosclerosis was of his native left circumflex and left main coronary arteries. Microscopic examination revealed acute myocardial infarction of the left atrium at the rupture site. The anatomy of atrial circulation as well as the pathology and consequences of atrial infarction are discussed.

Anatomical investigation of the sinus node artery using dual-source computed tomography

BACKGROUND

Few investigators have studied the anatomy of the sinus node artery (SNA) using noninvasive imaging modalities, so the objective of this study was to visualize the in-vivo 3-dimensional anatomical relations of the SNA using dual-source computed tomography (DSCT).

METHODS AND RESULTS

In the 101 patients included in this study, the visualization rate, anatomical type and diameter of the SNA, the distance between the orifice and coronary artery, and the terminal type of SNA were recorded. The visualization rate was 95.2% (96/101). Of 96 patients, 106 SNAs were detected among which 51 (48.1%, 51/106) originated from the right coronary artery, 52 (49.1%, 52/106) from the left circumflex artery, and 3 (2.7%, 3/106) from other branches. There were 3 types of SNA: right (n = 52), left (n = 45), and posterior (n = 9). The distance between the orifice of the right SNA and the right coronary sinus was 14.2+/-15.2 mm, for the left SNA it was 5.5+/-3.5 mm, and for the posterior SNA, 33.7+/-12.8 mm. The average diameter was 1.27+/-0.29 mm. The SNA approached the nodal tissue by 1 of 3 routes: retrocaval (51.5%), precaval (25.2%), or pericaval (22.3%).

CONCLUSION

The SNA can be visualized in vivo using DSCT, which is important for preoperative knowledge of its origin, course, termination, and anatomical type.

Prolonged sinus node dysfunction caused by obstruction of the sinus node artery occurring during coronary stenting

We report a unique case with prolonged sinus node dysfunction caused by accidental occlusion of the sinus node artery occurring during coronary stenting for a proximal right coronary lesion.

Sinus arrest caused by occlusion of the sinus node artery during percutaneous coronary intervention for lesions of the proximal right coronary artery

We examined the frequency of side-branch occlusion of the sinus node (SN) artery and of the subsequent sinus arrest in 80 consecutive patients who underwent percutaneous coronary intervention (PCI) for proximal right coronary artery (RCA) lesions. Side-branch occlusion of the SN artery occurred during PCI in 14 (17.5%) patients. Sinus arrest with junctional escape rhythm developed in 4 (28.6%) of these 14 patients. Temporary ventricular pacing was performed for one patient. The junctional escape rhythm disappeared in all of the patients within 3 days of the SN artery occlusion. The frequency of a single blood supply to the SN by the SN artery originating from the RCA did not differ significantly between the patients with and without sinus arrest (4/4 [100%]) vs 9/10 [90%]). In conclusion, although side-branch occlusion of the SN artery often occurs during PCI for proximal RCA lesions, where the SN artery originated, it does not always produce sinus arrest even in cases of a single blood supply to the SN by the SN artery originating from the RCA. Even though sinus arrest is caused by the occlusion of the SN artery, this bradyarrhythmia seems to disappear in the short term.