DISCUSSION
The main findings of this study demonstrate that catheter ablation can lead to a decrease in mean total psychiatric medications in PSVT patients that were being treated with psychiatric medications. Previous studies demonstrated that ablation improve subjective symptoms through scoring systems [7,8,10]. This is the first study that provides objective evidence that mean number of psychiatric medications significantly decrease in these patients.
Paroxysmal Supraventricular Tachycardia (PSVT) is defined as a clinical syndrome noted by the presence of regular and rapid tachycardia [1]. Palpitations, dyspnea, hyperventilation, syncope, sweating, chest pain, and anxiety are the most reported symptoms [2]. Our study demonstrated similar presentations with the most common complaint being palpitations. In a previous study, 67% of patients with PSVT had symptoms that were consistent with the diagnosis of panic disorder, based on the Diagnostic and Statistical Manual of Mental Disorders (DSM)-IV [6]. Per the updated DSM-V, the criteria remain similar and therefore PSVT could continue to remain mis-diagnosed as a panic or anxiety disorder [11].
It has been reported that anxiety may be exacerbated by PSVT episodes. The sudden onset of PSVT can trigger anxiety disorders in patients [3]. One study reported that anxiety disorder has been present in approximately 25% of patients with PSVT; interestingly, the same study reported that PSVT was unrecognized in over 50% of the time [6]. As anxiety levels increase, patients are at an increased risk for further PSVT [5,9]. Therefore, patients can often get caught between anxiety and panic attacks between episodes of PSVT. This confounds the clinical picture, leading to misdiagnosis, incorrect management and potentially escalating anti-anxiety medications.
Catheter ablation is a Class 1 recommendation for the treatment of PSVT based on the 2015 American College of Cardiology/ American Heart Association/ Heart Rhythm Society guidelines [1]. Ablation has a high success rate, greater than 93% dependent on the mechanism [12,13] with a minimal complication rate [12]. It is highly effective for eliminating further episodes of PSVT [14,15] and has been proven to be cost-effective when compared to chronic antiarrhythmic drug therapy [8, 16-19]. However, there has been less evidence on the effects of ablation on anxiety in patients with PSVT. Current studies utilized subjective scoring systems to demonstrate improvement in these psychiatric disorders. Yildrim et al utilized the WHOQOL-BRIEF domain scores [8, 20] and demonstrated a statistically significant improvement post-ablation. Papiashvilli et al utilized the State and Trait Anxiety Inventory (STATI) and found that PSVT patients had improved situational and general anxiety levels [7, 21]. The same group also utilized the Short Form health questionnaire (SF-36) and found significant improvement in physical, social, and emotional health scores after ablation [10, 22]. Our study further supports this data by providing objective evidence of the effect of PSVT ablation on anxiety disorders.
We examined the mean number of medications and found a significant decrease in the average number of psychiatric medications. We also examined different types of medications including SSRIs, SNRIs, anxiolytics such as bupropion, buspirone, and trazadone, benzodiazepines, and antipsychotics. These medications were chosen due to the current medical management of anxiety and panic disorders [23,24]. SSRIs and SNRIs are often the first line treatment for anxiety. Typically, one agent is chosen and titrated up to the maximum dose. If the medication does not provide a desired outcome, the patient is switched to another agent and the process is repeated. Cases that are refractory will be supplemented with other anxiolytics or benzodiazepines as needed [25]. If the anxiety is uncontrolled with the previous process, antipsychotics may be utilized [26]. Therefore, we wanted to look at the total number of psychiatric medications, as well as each individual subtype, as a measure of anxiety disorder severity. For patients with uncontrolled anxiety, we expect the average number of psychiatric medications to increase based on current guidelines. We found that patients with SVT ablation was associated with a decrease in the average number of psychiatric medications. Due to having similar symptoms, SVT may have been misdiagnosed as anxiety and panic disorders, leading to excessive psychiatric medications. Ablation then abated symptoms and may have led to decreased average number of psychiatric medications.
The main limitation of our study was the sample size. Other modes of managing anxiety, such as cognitive therapy, exist [27] but were not recorded. Larger prospective studies may be needed to further examine the relationship with psychiatric medications, cognitive therapy, and SVT ablation.