Cardiac Sympathetic Denervation: Procedure and Follow-Up in LQTS

Patients with congenital or acquired long QT syndrome face a constant threat of malignant ventricular arrhythmias triggered by surges in sympathetic activity. Beta-blockers remain the cornerstone of therapy, yet a meaningful subset of individuals continue to experience breakthrough events, syncope, or sudden cardiac death despite optimal medical management. Over several decades, left cardiac sympathetic denervation has emerged as a powerful adjunctive strategy for these high-risk patients.

In Australia, families dealing with channelopathies are often managed through multidisciplinary clinics in tertiary centres such as Royal Prince Alfred Hospital in Sydney, The Alfred in Melbourne, or the Royal Adelaide Hospital. These hubs coordinate genetic testing, electrophysiology consultation, and surgical referral, which is especially important for those living in regional areas of New South Wales or Queensland where access to subspecialists requires travel. The Australian Therapeutic Goods Administration oversees the devices and pharmacotherapies used, while Medicare supports many of the investigations through rebates.

The operation is most often performed as a minimally invasive video-assisted thoracoscopic procedure, sparing patients the morbidity of a large thoracotomy. When undertaken by an experienced thoracic surgeon working alongside a cardiac electrophysiologist, it can significantly blunt the sympathetic input that drives torsades de pointes and arrhythmic storms. This article outlines the physiological rationale, patient selection, operative steps, recovery, and long-term surveillance required to achieve the best possible outcomes.

Readers who manage these patients, whether in a quaternary referral hospital in Perth or in a private cardiology practice in Brisbane, will find practical guidance grounded in contemporary evidence. The aim is to support clinicians in counselling families, coordinating care, and recognising when referral for sympathetic denervation is appropriate.

The Physiological Basis for Sympathetic Modulation

The sympathetic nervous system exerts a profound influence on ventricular repolarisation, and its overactivity can precipitate torsades de pointes in susceptible individuals. In long QT syndrome, particularly genotypes 1 and 2, abrupt catecholamine surges during exercise, emotion, or auditory stimuli can trigger arrhythmic storms that are not fully suppressed by beta-blockade alone. Reducing noradrenaline release at the level of the stellate ganglion lowers this trigger burden.

Left cardiac sympathetic denervation achieves this by interrupting post-ganglionic sympathetic fibres that travel through the lower half of the left stellate ganglion and the first four thoracic ganglia. Removal of this neural input decreases the release of noradrenaline at the ventricular myocardium without producing the systemic side effects of high-dose pharmacological antiadrenergic therapy. The right-sided chain is generally left intact to preserve vagal reflexes and sinus node function.

Australian clinicians often cite the work of Schwartz and colleagues when explaining the concept to patients, and local protocols at institutions such as Westmead Hospital mirror international consensus. The physiological rationale is reinforced by holter monitoring and exercise testing, which frequently show reduced arrhythmic burden after denervation in appropriately selected individuals.

Selecting Candidates and Preparing for Surgery

Referral for sympathetic denervation is generally considered in patients who remain symptomatic despite maximally tolerated beta-blocker therapy, those with a history of cardiac arrest or recurrent syncope, and individuals who experience ICD shocks despite optimal device programming. Some families pursue surgery as a bridge to reduce shocks in younger patients, including children in whom device implantation carries particular challenges.

Pre-procedural assessment includes a thorough review of the genotype where known, ambulatory monitoring, exercise stress testing, and a careful review of medications. Drugs that prolong the QT interval, including certain antibiotics and antiemetics, are reviewed against the Australian Medicines Handbook and discontinued where feasible. Anaesthesia consultation addresses airway considerations and the use of agents such as propofol and remifentanil that have favourable electrophysiological profiles.

Genetic counselling is offered to first-degree relatives, an important step given the autosomal dominant inheritance pattern of many variants. In Australia, this is often provided through clinical genetics services attached to tertiary paediatric or cardiology departments, with Medicare rebates available for genetic testing when criteria are met. Families are counselled about the expected reduction in events rather than the guarantee of a cure, which is critical for informed consent.

Surgical Technique and Intraoperative Management

The procedure is typically performed under general anaesthesia with single-lung ventilation through a double-lumen endotracheal tube. The patient is positioned supine with the left shoulder elevated, and two or three port sites are used for thoracoscopic access. The surgeon identifies the left stellate ganglion and the thoracic sympathetic chain, removing the lower half of the stellate ganglion along with the T2 to T4 ganglia.

Care is taken to preserve the upper portion of the stellate ganglion to minimise the risk of Horner syndrome, though transient ptosis and miosis can still occur. The use of intraoperative neuromonitoring and meticulous haemostasis is essential, particularly in young patients with delicate tissues. The pleural space is usually drained with a small-bore chest tube, which is removed within twenty-four to forty-eight hours.

Coordination with electrophysiology colleagues allows intraoperative mapping where indicated, particularly in patients undergoing concurrent ablation for ventricular arrhythmias. Recent reviews of epicardial ablation techniques provide useful parallels in surgical planning, even when catheter and surgical approaches are not combined in the same session.

Immediate Post-Operative Care and Early Recovery

After surgery, patients are typically monitored in a high-dependency unit for the first twenty-four hours with continuous telemetry. Pain control is achieved with a combination of intercostal blocks, paracetamol, and short courses of opioids, reflecting the increasing emphasis on opioid stewardship in Australian hospitals. Early mobilisation is encouraged, and most patients are discharged within three to five days once chest drains are removed and mobility is restored.

Complications are uncommon but include pneumothorax, chylothorax, haemothorax, transient Horner syndrome, and rare neuralgia. Patients and families are educated about warning signs such as increasing shortness of breath or fever, with clear instructions on when to present to their local emergency department. For those living in rural South Australia or Western Australia, this often involves a documented plan for transfer to a tertiary centre.

Beta-blocker therapy is generally continued throughout the perioperative period, although dosing may be temporarily adjusted on the morning of surgery and reintroduced as soon as oral intake is established. Device interrogation is performed before discharge to confirm appropriate detection and therapy settings, particularly in patients with previously implanted ICDs.

Long-Term Follow-Up and Surveillance

Long-term follow-up combines cardiology review, genetic counselling, and device interrogation at intervals guided by individual risk. Most Australian clinicians schedule visits every six to twelve months, with additional review after any change in medication, after pregnancy, or following a syncopal event. Ambulatory monitoring and periodic exercise testing are used to gauge ongoing arrhythmia burden and the adequacy of therapy.

Patients are encouraged to maintain a healthy lifestyle, including adequate hydration and avoidance of triggering activities during hot summer months when electrolyte shifts can occur. Sports participation is discussed individually, with most patients cleared for recreational activity, though competitive endurance sport may be restricted in certain genotypes. Schools and workplaces are briefed on the individual's condition and emergency management plan.

Education about drug safety remains a lifelong priority. Families are provided with updated lists of contraindicated medications and instructed to verify any new prescription through their pharmacist or cardiologist. Many Australian patients use the national electronic health record to share this information with treating clinicians in different states, particularly when travelling between Sydney and Perth for work or family reasons.

Outcomes, Integration, and the Broader Arrhythmia Landscape

When performed by experienced teams, left cardiac sympathetic denervation reduces cardiac events by approximately seventy to ninety per cent in appropriately selected patients, with the greatest benefit seen in those with recurrent ICD shocks and in younger cohorts. It does not eliminate the need for ongoing beta-blocker therapy, nor does it replace the defibrillator in patients who meet criteria for one. Instead, it serves as a complementary layer of protection that lowers the frequency of triggering events.

The procedure also has a role in the broader landscape of arrhythmia management, including selected patients with catecholaminergic polymorphic ventricular tachycardia and those with arrhythmogenic conditions complicated by structural heart disease. Coordinated decision-making across specialties is essential, particularly when patients develop additional cardiovascular conditions over their lifetime. The journal's recent examination of TAVR arrhythmia outcomes illustrates how rhythm considerations extend well beyond the channelopathies and into valvular heart disease.

For Australian patients and clinicians, the message is that sympathetic denervation is no longer a last-resort measure but a well-established component of the modern LQTS toolkit. Timely referral, careful patient selection, and structured follow-up are the pillars of success, and the procedure should be discussed whenever breakthrough events occur despite optimised medical therapy.

Readers are invited to explore the journal's themed collections on cardiac sympathetic denervation, submit their own research through the online portal, or contact the editorial office with questions about themed issues and special supplements. The Asia Pacific Heart Rhythm Society and Japanese Heart Rhythm Society host regular educational symposia in the region, providing further opportunities for engagement and collaboration.