Takotsubo syndrome following radiofrequency ablation of atrial fibrillation in a patient with coronary artery anomaly: a case report

Case Report and Literature Review of an Anomalous Course of the Left Main Coronary Artery (LMCA) Arising From the Right Sinus of Valsalva (RSV) Presenting as Takotsubo Cardiomyopathy

Takotsubo cardiomyopathy (TC) mimics myocardial infarction with symptoms like chest pain, electrocardiogram (EKG) changes, and elevated troponin levels, although it typically features normal coronary arteries upon angiography. While often asymptomatic, coronary artery anomalies (CAAs) can cause intermittent vasospasm and endothelial dysfunction, potentially inducing TC. We report the case of a 74-year-old female with a history of hypertension, hyperlipidemia, and peripheral artery disease, who presented with sudden onset chest pain. Initial EKG and elevated troponin suggested myocardial infarction. However, coronary angiography revealed an anomalous left main coronary artery (LMCA) originating from the right coronary artery (RCA), with no significant stenosis. Subsequent transthoracic echocardiography indicated TC, with the left ventricular ejection fraction improving from 35-40% to 60-65% within days. Cardiac computed tomography angiography (CCTA) revealed that the anomalous LMCA originated from the common trunk at the right sinus of Valsalva (RSV), which further continued as a large, dominant RCA. The LMCA branched into a small to moderate left anterior descending artery (LAD) and a non-dominant left circumflex artery (LCx). The LMCA followed a prepulmonic/anterior course, while the LCx took an interarterial course between the aorta and pulmonary artery. The patient was referred for further surgical evaluation. We conclude that the CAA was an incidental finding and was not related to underlying TC. Although rare, this case suggests a possible correlation between CAAs and a predisposition to stress-induced cardiomyopathy, warranting further investigation.

The Intrinsic Cardiac Nervous System: From Pathophysiology to Therapeutic Implications

The cardiac autonomic nervous system (CANS) plays a pivotal role in cardiac homeostasis as well as in cardiac pathology. The first level of cardiac autonomic control, the intrinsic cardiac nervous system (ICNS), is located within the epicardial fat pads and is physically organized in ganglionated plexi (GPs). The ICNS system does not only contain parasympathetic cardiac efferent neurons, as long believed, but also afferent neurons and local circuit neurons. Thanks to its high degree of connectivity, combined with neuronal plasticity and memory capacity, the ICNS allows for a beat-to-beat control of all cardiac functions and responses as well as integration with extracardiac and higher centers for longer-term cardiovascular reflexes. The present review provides a detailed overview of the current knowledge of the bidirectional connection between the ICNS and the most studied cardiac pathologies/conditions (myocardial infarction, heart failure, arrhythmias and heart transplant) and the potential therapeutic implications. Indeed, GP modulation with efferent activity inhibition, differently achieved, has been studied for atrial fibrillation and functional bradyarrhythmias, while GP modulation with efferent activity stimulation has been evaluated for myocardial infarction, heart failure and ventricular arrhythmias. Electrical therapy has the unique potential to allow for both kinds of ICNS modulation while preserving the anatomical integrity of the system.

Ischemia-induced ventricular proarrhythmia and cardiovascular autonomic dysreflexia after cardioneuroablation

BACKGROUND

Cardioneuroablation (CNA) is an attractive treatment of vasovagal syncope. Its long-term efficacy and safety remain unknown.

OBJECTIVE

The purpose of this study was to develop a chronic porcine model of CNA to examine the susceptibility to ventricular tachyarrhythmia (ventricular tachycardia/ventricular fibrillation [VT/VF]) and cardiac autonomic function after CNA.

METHODS

A percutaneous CNA model was developed by ablation of left- and right-sided ganglionated plexi (n = 5), confirmed by histology. Reproducible bilateral vagal denervation was confirmed after CNA by extracardiac vagal nerve stimulation (VNS) and histology. Chronic studies included 16 pigs randomized to CNA (n = 8) and sham ablation (n = 8, Control). After 6 weeks, animals underwent hemodynamic studies, assessment of cardiac sympathetic and parasympathetic function using sympathetic chain stimulation and direct VNS, respectively, and proarrhythmic potential after left anterior descending (LAD) coronary artery ligation.

RESULTS

After CNA, extracardiac VNS responses remained abolished for 6 weeks despite ganglia remaining in ablated ganglionated plexi. In the CNA group, direct VNS resulted in paradoxical increases in blood pressure, but not in sham-ablated animals (CNA group vs sham group: 8.36% ± 7.0% vs -4.83% ± 8.7%, respectively; P = .009). Left sympathetic chain stimulation (8 Hz) induced significant corrected QT interval prolongation in the CNA group vs the sham group (11.23% ± 4.0% vs 1.49% ± 4.0%, respectively; P < .001). VT/VF after LAD ligation was more prevalent and occurred earlier in the CNA group than in the control group (61.44 ± 73.7 seconds vs 245.11 ± 104.0 seconds, respectively; P = .002).

CONCLUSION

Cardiac vagal denervation is maintained long-term after CNA in a porcine model. However, chronic CNA was associated with cardiovascular dysreflexia, diminished cardioprotective effects of cardiac vagal tone, and increased susceptibility to VT/VF in ischemia. These potential long-term negative effects of CNA suggest the need for rigorous clinical studies on CNA.

Multicenter retrospective database evaluation of Takotsubo syndrome in subjects undergoing catheter ablation for atrial fibrillation

Background

Intracardiac catheter ablation for atrial fibrillation with pulmonary vein isolation may result in Takotsubo syndrome (TS), but the frequency, predisposing factors (age, sex, mental health disorders), and outcomes are currently unknown. This study sought to assess the frequency, predisposing factors, and outcomes of subjects who underwent intracardiac catheter ablation for atrial fibrillation with pulmonary vein isolation and were diagnosed with TS.

Methods

This was a retrospective observational cohort study utilizing TriNetX® electronic health record (EHR) data. We included subjects aged older than 18 years who underwent intracardiac catheter ablation for atrial fibrillation with pulmonary vein isolation. The study population was divided into two groups (no TS diagnostic code presence and TS diagnostic code presence). We analyzed the distributions of age, sex, race, diagnostic codes, common terminology procedures (CPT), and vasoactive medication codes and examined mortality rate within 30 days.

Results

We included 69,116 subjects. Of these, 27 (0.04%) had a TS diagnostic code, the cohort was comprised mostly of females [17 (63.0%)], and 1 (3.7%) death within 30 days was reported. There were no significant differences in age and frequency of mental health disorders between those patients in TS and non-TS cohorts. Adjusting for age, sex, race, ethnicity, patient regionality, and mental health disorder diagnostic code, those patients who developed TS had a significantly higher odds of dying in 30 days after catheter ablation compared to those without TS (OR = 15.97, 95% CI: 2.10-121.55, p = .007).

Conclusions

Approximately 0.04% of subjects who underwent intracardiac catheter ablation of atrial fibrillation by pulmonary vein isolation had a subsequent diagnostic code of TS. Further study is needed to determine whether there are predisposing factors associated with the development of TS in subjects who undergo catheter ablation of atrial fibrillation by pulmonary vein isolation.