Late Outcomes of Surgical Ablation for Inappropriate Sinus Tachycardia

Abstract

Background: Inappropriate sinus tachycardia (IST) is a rare clinical disorder characterized by an elevated resting heart rate and an exaggerated rate response to exercise or autonomic stress. Pharmacologic therapy and catheter ablation are considered first-line treatments for IST but can yield suboptimal relief of symptoms. The results of surgical ablation at our center were reviewed for patients with refractory IST.

Methods: Between 1987 and 2018, 18 patients underwent surgical sinoatrial (SA) node isolation for treatment-refractory IST. All 18 patients had previously failed pharmacologic therapy, and 15 patients had failed catheter ablation of the SA node.

Results: Ten patients underwent a median sternotomy, and 8 patients underwent a minimally invasive right thoracotomy. The SA node was isolated with the use of surgical incisions, cryoablation, or bipolar radiofrequency ablations. Sinus tachycardia was eliminated in 100% of patients in the immediate postoperative period. Long-term follow-up data were available for 17 patients, with a mean follow-up of 11.4 ± 7.9 years. At last follow-up, 100% of patients were free from recurrent symptomatic IST. More than 80% of patients were completely asymptomatic, whereas 3 patients reported occasional palpitations. Four patients were on β-blockers, and 5 patients required subsequent pacemaker implantation. All 8 patients who underwent minimally invasive isolation were in normal sinus rhythm at last follow-up, and only 1 patient complained of palpitations.

Conclusions: Surgical isolation of the SA node is a feasible treatment for IST refractory to pharmacologic therapy and catheter ablation. A minimally invasive surgical approach offers a less morbid alternative to traditional median sternotomy.

Copyright © 2019 The Society of Thoracic Surgeons. Published by Elsevier Inc. All rights reserved.

Figures

Figure 1.

Position of the bipolar radiofrequency clamp used to isolate the sinoatrial node and surrounding right atrial tissue. Reproduced from Kreisel and colleagues with permission from The Journal of Thoracic and Cardiovascular Surgery, Elsevier. See the Video for more details.

Figure 2.

(A) Inferior lead (II) of intraoperative electrocardiogram in patient 16 undergoing minimally invasive surgical ablation. A baseline electrocardiogram demonstrated an upright P-wave with a change in heart rate (HR) from 108 beats/min to 136 beats/min during the administration of isoproterenol. There was no reaction to isoproterenol after ablation, which led to an atrial rhythm with negative P-wave morphologic characteristics. (B) Twelve-lead electrocardiogram showing stable postoperative atrial escape rhythm. Note negative P-wave morphologic characteristics in inferior leads II, III, and aVF.

Figure 3.

Our general approach to patients with symptomatic sinus tachycardia. (CBC, complete blood count; CMP, comprehensive metabolic panel; ECG, electrocardiogram; H&P, history and physical; IST, inappropriate sinus tachycardia.)