Right diaphragmatic paralysis following endocardial cryothermal ablation of inappropriate sinus tachycardia

Pregnancy-related inappropriate sinus tachycardia: A cohort analysis of maternal and fetal outcomes

Background

Little literature exists regarding the syndrome of inappropriate sinus tachycardia during pregnancy. We aimed to further understand the natural history of inappropriate sinus tachycardia in pregnancy, and to explore maternal and fetal outcomes.

Methods

A retrospective, observational cohort analysis of 19 pregnant women who presented with inappropriate sinus tachycardia.

Results

42% attended the emergency department on more than one occasion with symptoms of inappropriate sinus tachycardia; 32% required hospital admission and 26% required pharmacological therapy. There were no maternal deaths, instances of heart failure or acute coronary syndrome, and no thromboembolic or haemorrhagic complications during pregnancy. Rates of caesarean section were similar to the background rate of our unit (32% and 27%, respectively). Rates of induction were notably elevated (58% vs 25%).

Conclusion

Inappropriate sinus tachycardia in pregnancy is associated with high rates of hospitalization and induction of labour, which may not be mandatory given the clinical findings in this group of women.

Sinus node sparing novel hybrid approach for treatment of inappropriate sinus tachycardia/postural sinus tachycardia: multicenter experience

BACKGROUND

The ideal treatment of inappropriate sinus tachycardia (IST) and postural orthostatic tachycardia syndrome (POTS) still needs to be defined. Medical treatments yield suboptimal results. Endocardial catheter ablation of the sinus node (SN) may risk phrenic nerve damage and open-heart surgery may be accompanied by unjustified invasive risks.

METHODS

We describe our first multicenter experience of 255 consecutive patients (235 females, 25.94 ± 3.84 years) having undergone a novel SN sparing hybrid thoracoscopic ablation for drug-resistant IST (n = 204, 80%) or POTS (n = 51, 20%). As previously described, the SN was identified with 3D mapping. Surgery was performed through three 5-mm ports from the right side. A minimally invasive approach with a bipolar radiofrequency clamp was used to ablate targeted areas while sparing the SN region. The targeted areas included isolation of the superior and the inferior caval veins, and a crista terminalis line was made. All lines were interconnected.

RESULTS

Normal sinus rhythm (SR) was restored in all patients at the end of the procedure. All patients discontinued medication during the follow-up. After a blanking period of 6 months, all patients presented stable SR. At a mean of 4.07 ± 1.8 years, normal SN reduction and chronotropic response to exercise were present. In the 51 patients initially diagnosed with POTS, no syncope occurred. During follow-up, pericarditis was the most common complication (121 patients: 47%), with complete resolution in all cases. Pneumothorax was observed in 5 patients (1.9%), only 3 (1.1%) required surgical drainage. Five patients (1.9%) required a dual-chamber pacemaker due to sinus arrest > 5 s.

CONCLUSIONS

Preliminary results of this multicenter experience with a novel SN sparing hybrid ablation of IST/POTS, using surgical thoracoscopic video-assisted epicardial ablation combined with simultaneous endocardial 3D mapping may prove to be an efficient and safe therapeutic option in patients with symptomatic drug-resistant IST and POTS. Importantly, in our study, all patients had a complete resolution of the symptoms and restored normal SN activity.

Sinus Node Sparing Hybrid Thoracoscopic Ablation Outcomes in Patients with Inappropriate Sinus Tachycardia (SUSRUTA-IST) Registry

BACKGROUND

Medical treatment of inappropriate sinus tachycardia (IST) remains suboptimal. Radiofrequency sinus node (RF-SN) ablation has poor success and higher complication rates.

OBJECTIVE

We aimed to compare clinical outcomes of the novel SN sparing hybrid ablation technique with those of RF-SN modification for IST management.

METHODS

This is a multicenter prospective registry comparing the SN sparing hybrid ablation strategy with RF-SN modification. The hybrid procedure was performed using an RF bipolar clamp, isolating superior vena cava/inferior vena cava with the creation of a lateral line across the crista terminalis while sparing the SN region (identified by endocardial 3-dimensional mapping). RF-SN modification was performed by endocardial and/or epicardial mapping and ablation at the site of earliest atrial activation.

RESULTS

Of the 100 patients (hybrid ablation group, n = 50; RF-SN group, n = 50), 82% were women, and the mean age was 22.8 years. Normal sinus rhythm and rate were restored in all patients in the hybrid group (vs 84% in the RF-SN group; P = .006). Hybrid ablation was associated with significantly better improvement in mean daily heart rate and peak 6-minute walk heart rate compared with RF-SN ablation. The RF-SN group had a significantly higher rate of redo procedures (100% vs 8%; P < .001), phrenic nerve injury (14% vs 0%; P = .012), lower acute pericarditis (48% vs 92%; P < .0001), permanent pacemaker implantation (50% vs 4%; P < .0001) than did the hybrid ablation group.

CONCLUSION

The novel sinus node sparing hybrid ablation procedure appears to be more efficacious and safer in patients with symptomatic drug-resistant IST with long-term durability than RF-SN ablation.

Sinus Node Sparing Novel Hybrid Approach for Treatment of Inappropriate Sinus Tachycardia/Postural Orthostatic Sinus Tachycardia With New Electrophysiological Finding

The ideal treatment of Inappropriate Sinus Tachycardia (IST) and Postural Orthostatic Tachycardia Syndrome (POTS) still needs to be defined. Medical treatment yields suboptimal results, endocardial ablation of the sinus node (SN) may risk phrenic nerve damage and open heart surgery may be accompanied by unjustified invasive risks. We describe our first experience of 50 consecutive patients (41 females, 22.83 ± 3.91 years) having undergone a novel hybrid thoracoscopic ablation for drug resistant IST (n = 39, 78%) or POTS (n = 11, 22%). The SN was identified with the help of 3D mapping. Surgery was performed through 3 (5 mm) ports from the right side. A minimally invasive approach with a radio frequency bipolar clamp was utilized to a new target sparing the SN region, to isolate the superior and the inferior caval veins, and a crista terminalis line was made. All lines were interconnected. Normal SR was restored in all patients at the end of the procedure. All patients discontinued medication during the follow-up. After a blanking period of 6 months all patients presented stable SR. At a mean of 28.4 ± 1.2 months, normal SN ruction and chronotropic response to exercise was present. In the 11 patients initially diagnosed with POTS, no syncope occurred. During the follow-up, pericarditis was the most common complication (39 patients; 78%) with complete resolution in all cases. In conclusions the preliminary results of our first experience with a SN sparing novel hybrid ablation of IST/POTS, using surgical thoracoscopic video-assisted epicardial ablation combined with concomitant endocardial 3D mapping may prove an efficient and safe therapeutic option in patients with symptomatic drug resistant IST and POTS. Importantly, in our study all patients had a complete resolution of the symptoms and restored normal SN activity.

Minimally invasive thoracoscopic surgery is an effective approach for treating inappropriate sinus tachycardia

INTRODUCTION

Inappropriate sinus tachycardia (IST) is characterized by increased heart rate out of proportion to normal physiologic demand. IST ablation is challenging for the electrophysiology community due to the epicardial location of the sinus node and the risk of phrenic nerve (PN) injury during catheter ablation. In this study, we investigated the safety and efficacy of a minimally invasive thoracoscopic surgery for elimination of IST.

METHODS

Patients with IST who failed medical therapy or endocardial ablation underwent minimally invasive thoracoscopic epicardial ablation. Epicardial activation mapping was performed to identify the earliest activation site and any possible migration of earliest activation along the lateral right atrium. The PN in each patient was protected by a pericardial retraction suture.

RESULTS

From 1 January 2000 to 15 June 2018, 10 patients (eight females and two males) underwent minimally invasive thoracoscopic IST ablation. Mean age of the patients was 36.7 ± 12.5 years. Mean baseline sinus rate was 113.8 ± 21.8 beats per minute. After surgery, the mean heart rate significantly decreased to 79.8 ± 8.2 at postoperative day 1 and to 75.8 ± 8.1 at day 30 (both P < .001). No in-hospital death, stroke, or PN injury occurred. One patient required reintubation, one patient developed postoperative pericarditis, and another patient had a pulmonary embolus. Median follow-up was 6 months (range, 1-50). Freedom from reintervention was 88% at 6 months.

CONCLUSION

Minimally invasive thoracoscopic ablation for IST is a safe and effective approach that preserves the phrenic nerve. Due to the possibility of IST activation site migration, continued follow-up after surgery is required.

Inappropriate sinus tachycardia in pregnancy: a benign phenomena?

The syndrome of inappropriate sinus tachycardia (IST) is a well-described and generally benign condition outside pregnancy. There is, however, little information in the literature about IST during pregnancy and nothing about the likely mechanism in such cases. Equally there is a paucity of information about the effects on maternal and fetal well-being in patients who develop IST during pregnancy. Here, we describe the case of a woman who developed IST for the first time during pregnancy. We have first given a brief clinical summary of events and then follow this with the patient's personal account which she has written herself specifically for this case report. We believe that this case highlights some of the important issues associated with the condition when it occurs during pregnancy. We hope that the publication of this case report will increase the awareness of IST during pregnancy. This is important as we believe that the correct diagnosis and understanding of the condition and its consequences will allow clinicians to manage women afflicted by the condition empathetically and appropriately.

Strategies for phrenic nerve preservation during ablation of inappropriate sinus tachycardia

BACKGROUND

Radiofrequency (RF) ablation can alleviate drug-refractory inappropriate sinus tachycardia (IST). However, phrenic nerve (PN) injury and other complications limit its use.

OBJECTIVE

The purpose of this study was to characterize the maneuvers used to avoid PN injury and the long-term clinical outcomes.

METHODS

The study consisted of a retrospective analysis of consecutive patients who underwent ablation for IST.

RESULTS

RF ablation was performed on 13 consecutive female patients with drug-refractory IST. Eleven patients exhibited PN capture at desired ablation sites. In 1 patient, PN capture was not continuous throughout the respiratory cycle and ventilation holding sufficed to avoid PN injury. In 10 patients, pericardial access (PA) and balloon insertion was required. Initially (n = 4) a posterior PA was used, which was replaced by an anterior PA in the subsequent 6 cases. PA to optimal balloon positioning time was significantly lower in anterior vs posterior PA (16.3 ± 6 minutes vs 58 ± 21.3 minutes, P = .01), as was fluoroscopy time (15.66 ± 16.72 min vs 35.9 ± 1.8 min, P = .03). RF ablation successfully reduced sinus rate to <90 bpm in 13 of 13 patients. Procedure times and total RF times were not significantly different in anterior vs posterior PA. Major complications occurred in 2 patients, including unremitting pericardial bleeding requiring open-chested repair in 1 patient and sinus pauses mandating pacemaker implantation in the other patient. Long-term symptom control after follow-up of 811 ± 42 days was successful in 84.6%.

CONCLUSION

Ventilation holding and/or pericardial balloon insertion are frequently warranted in IST ablation. Anterior PA appears to facilitate the procedure over posterior PA.

Catheter ablation of inappropriate sinus tachycardia

Catheter ablation for inappropriate sinus tachycardia (IST) is recommended for patients symptomatic for palpitations and refractory to other treatments. The current approach consists in sinus node modification (SNM), achieved by ablation of the cranial part of the sinus node to eliminate faster sinus rates while trying to preserve chronotropic competence. This approach has a limited efficacy, with a very modest long-term clinical success. To overcome this, proper patient selection is crucial and an epicardial approach should always be considered. This brief review will discuss the current role and limitations of catheter ablation in the management of patients with IST.