Left Cardiac Sympathetic Denervation for Long QT Syndrome: 50 Years' Experience Provides Guidance for Management.

OBJECTIVES: This study sought to report our single-center experience with left cardiac sympathetic denervation (LCSD) for long QT syndrome (LQTS) since 1973. BACKGROUND: LCSD is still underutilized because clinicians are often uncertain whether to use it versus an implantable cardioverter-defibrillator (ICD). METHODS: We performed LCSD in 125 patients with LQTS (58% women, mean QT interval corrected for frequency [QTc] 527 ± 60 ms, 90% on beta blockers) with a follow-up of 12.9 ± 10.3 years. They were retrospectively divided into 4 groups according to the clinical/genetic status: very high risk (n = 18, symptomatic in the first year of life or with highly malignant genetics), with aborted cardiac arrest (ACA) (n = 31), with syncope and/or ICD shocks on beta blockers (n = 45), in primary prevention (n = 31). RESULTS: After LCSD, 17% in the very high risk group remained asymptomatic, compared with 52%, 47%, and 97% in the other 3 groups (P < 0.0001), with an overall 86% decrease in the mean yearly cardiac event rate (P < 0.0001). Among 45 patients with only syncope/ICD shocks before LCSD, none had ACA/sudden death as first symptom after LCSD and a 6-month post-LCSD QTc <500 ms predicted excellent outcome. Patients with a QTc ≥500 ms have a 50% chance of shortening it by an average of 60 ms. LCSD results are not affected by common genotypes. CONCLUSIONS: We provide definitive evidence for the long-term efficacy of LCSD in LQTS. The degree of antiarrhythmic protection is influenced by patient's specificity and amount of QTc shortening. This novel approach to the analysis of the outcome allows cardiologists to rationally decide and tailor their management strategies to the individual features of their patients.

Video-thoracoscopic left cardiac sympathetic denervation for long-QT syndrome.

BACKGROUND: Congenital long-QT syndrome represents the most common cardiac channelopathy and manifests as potentially lethal ventricular arrhythmias. Prevention strategies include beta-blockade pharmacotherapy, implantable cardioverter-defibrillators, and left cardiac sympathetic denervation, which can increase the threshold for ventricular fibrillation. Herein, we report our experience with video-assisted thoracoscopic left cardiac sympathetic denervation. METHODS: We performed a retrospective review of the electronic medical records of all patients with congenital long-QT syndrome who underwent video-assisted thoracoscopic left cardiac sympathetic denervation at our institution. RESULTS: From September 2009 to May 2016, 6 patients with a mean age of 30.5 years (range 20-47 years) underwent video-assisted thoracoscopic left cardiac sympathetic denervation for medically refractory long-QT syndrome. All patients had an uneventful recovery and were discharged 1-3 days after the operation. At a median follow-up of 14 months (range 12-60 months), 4 patients had no cardiac events while 2 experienced 1 episode of arrhythmic syncope and 1 episode of appropriate implantable cardioverter-defibrillator shock. Following surgery, the mean annual cardiac events in the study cohort decreased from 2.13 to 0.33 (p = 0.004) and the mean corrected QT interval reduced from 560 ms to 491 ms (p = 0.006). CONCLUSIONS: Video-assisted thoracoscopic left cardiac sympathetic denervation is a safe and effective therapy in patients with congenital long-QT syndrome who continue to suffer from recurrent life-threatening arrhythmias or frequent implantable cardioverter-defibrillator discharges despite maximum tolerated doses of beta blockers.

Left Cardiac Sympathetic Denervation Monotherapy in Patients With Congenital Long QT Syndrome.

BACKGROUND: Videoscopic left cardiac sympathetic denervation (LCSD) is an effective antifibrillatory, minimally invasive therapy for patients with potentially life-threatening arrhythmia syndromes like long QT syndrome (LQTS). Although initially used primarily for treatment intensification following documented LQTS-associated breakthrough cardiac events while on beta-blockers, LCSD as 1-time monotherapy for certain patients with LQTS requires further evaluation. We are presenting our early experience with LCSD monotherapy for carefully selected patients with LQTS. METHODS: Among the 1400 patients evaluated and treated for LQTS, a retrospective review was performed on the 204 patients with LQTS who underwent LCSD at our institution since 2005 to identify the patients where the LCSD served as stand-alone, monotherapy. Clinical data on symptomatic status before diagnosis, clinical, and genetic diagnosis, and breakthrough cardiac events after diagnosis were analyzed to determine efficacy of LCSD monotherapy. RESULT: Overall, 64 of 204 patients (31%) were treated with LCSD alone (37 [58%] female, mean QTc 466±30 ms, 16 [25%] patients were symptomatic before diagnosis with a mean age at diagnosis 17.3±11.8 years, 5 had [8%] ≥1 breakthrough cardiac event after diagnosis, and mean age at LCSD was 21.1±11.4 years). The primary motivation for LCSD monotherapy was an unacceptable quality of life stemming from beta-blocker related side effects (ie, beta-blocker intolerance) in 56/64 patients (88%). The underlying LQTS genotype was LQT1 in 36 (56%) and LQT2 in 20 (31%). There were no significant LCSD-related surgical complications. With a mean follow-up of 2.7±2.4 years so far, only 3 patients have experienced a nonlethal, post-LCSD breakthrough cardiac event in 180 patient-years. CONCLUSIONS: LCSD may be a safe and effective stand-alone therapy for select patients who do not tolerate beta-blockers. However, LCSD is not curative and patient selection will be critical when potentially considering LCSD as monotherapy.

Left cardiac sympathetic denervation in the management of long QT syndrome and catecholaminergic polymorphic ventricular tachycardia: A meta-regression.

BACKGROUND: Left cardiac sympathetic denervation (LCSD) has been proposed as useful therapy for long QT syndrome (LQTS) and catecholaminergic polymorphic ventricular tachycardia (CPVT), in addition to anti-arrhythmic agents and implantable cardioverter defibrillators. This study aimed to assess the current evidence for LCSD and compare the open vs the video-assisted thoracoscopic surgery (VATS) approaches. METHODS: MEDLINE, Embase and Cochrane library databases were searched up to December 2018 for studies reporting the long-term outcomes of LCSD in LQTS, CPVT patients. The incidence of cardiac events (CEs) before and after surgery, the change in QTc interval, and surgical complications were pooled to estimate the efficacy of LCSD. Meta-regression was used to estimate the effects of surgical approach (open vs VATS) on outcomes following LCSD. RESULTS: Twenty-seven papers met our inclusion criteria (647 patients). VATS was used in 408 patients (63.1%), open surgery in 239 (36.9%). Mean follow-up was 32.3 ± 32.5 months. Postsurgery, 398/585 patients (68.0%) were free of CEs and QTc decreased from 522 ± 61.6 ms to 494 ± 52.3 ms. Meta-regression showed no differences between the two approaches in the incidence of CEs and surgical complications. VATS was associated with a smaller reduction in QTc (ß-coefficient -20.04, 95% CI -36.82 to -3.27, P = .019). CONCLUSIONS: LCSD was associated with a reduction in the incidence of CEs in LQTS, CPVT patients and in the duration of QTc. Open surgery was associated with a greater reduction in QTc. Due to the limitations that hindered our study, a randomized trial is warranted to fully establish LCSD safety and efficacy.

The Effect of Left Cardiac Sympathetic Denervation on Exercise in Patients With Long QT Syndrome.

OBJECTIVES: This study evaluated the effect of left cardiac sympathetic denervation (LCSD) on heart rate, cardiac contractility, and cardiopulmonary fitness in human subjects. BACKGROUND: The primary treatment for long QT syndrome (LQTS) is beta-blocker (BB) therapy, but some patients experience breakthrough cardiac events or intolerable side effects. LCSD provides a significant antifibrillatory, protective effect in LQTS. However, the effect of LCSD on cardiopulmonary fitness in humans has not been previously described. METHODS: A retrospective analysis of patients with LQTS and LCSD (2006 to 2017) who had both pre- and post-LCSD exercise stress tests (N = 55; 39 females; mean age at LCSD 22 ± 12 years; mean follow-up 5.1 ± 2.5 years; 36 patients with LQT1; 15 patients with LQT2). Forty patients (73%) were receiving BBs pre-LCSD. RESULTS: Mean peak heart rate before LCSD was 143 ± 23 beats/min, mean peak oxygen consumption (VO2) was 32 ± 10 ml/kg/min, and mean peak respiratory exchange ratio was 1.14 ± 0.12. There was no difference in peak heart rate, peak VO2, peak QTc, or respiratory exchange ratio pre- and post-LCSD. To evaluate the isolated effect of LCSD, the study performed a subset analysis of patients with LCSD monotherapy (n = 10) or no change in BB dose (n = 12). Patient-matched pre- and post-LCSD exercise testing showed no difference in heart rate, VO2, or left ventricular function following LCSD. CONCLUSIONS: LCSD provides increased protection from an LQTS-triggered event without negatively affecting peak heart rate, cardiopulmonary fitness, or cardiac contractility, as assessed by both treadmill exercise stress testing and echocardiography.

Quantifying Long QT Syndrome in Obese Sleep Apnea Patients Undergoing Roux-en-Y Gastric Bypass Surgery.

Obstructive Sleep Apnea/Hypopnea Syndrome (OSAHS) is sleep-disordered breathing distinguished by repetitive cessation or reduction of airflow due to the collapse or narrowing of the upper airway during sleep with continued respiratory effort. A high level of incidence of OSAHS is correlated with obesity. Both severely obese patients and OSAHS patients manifest Long QT Syndrome (LQTS). It is reported that most obese patients undergoing weight reduction surgery positively reverse symptoms of LQST. Also, severely obese OSAHS undergoing the same surgery report alleviation of OSAHS symptoms. In this study, we presented preliminary results of the changes in QT and QTc intervals for obese OSAHS patients undergoing Roux-en-Y Gastric Bypass (RYGB) surgery and had their weight reduced, and were treated from OSAHS post-RYGB surgery. We developed an algorithm to detect the different waveforms in the ECG signal and calculated QT and QTc intervals. Results comparing the changes in the QT and QTc pre- and post-RYGB surgery for four apneic subjects (Aged 37.0 ± 8.9 years, Pre-RYGB BMI 51.7 ± 10.1 kg/m2, Post-RYGB BMI 35.6 ± 7.9 kg/m2) were contrasted with a control group of 3 non-apneic subjects (Aged 32.7 ± 7.0 years, Pre-RYGB BMI 50.8 ± 11.8 kg/m2, Post-RYGB BMI 31.6 ± 2.9 kg/m2) who underwent the same surgery. The results suggest that although the RYGB surgery is successful in weight loss and OSAHS symptoms reduction, apneic patients may continue to have non-reversible LQTS despite long-term weight reduction.

Thoracoscopic Sympathectomy for Long QT Syndrome. Literature Review and Case Study.

BACKGROUND: Multiple case studies have suggested that video-assisted thoracoscopic sympathectomy (VATS) reduces the occurrence and frequency of symptoms in long QT syndrome (LQTS) [1,2,3]. To date there has not been a literature review to report on the short-term and long-term outcomes of this procedure. Our primary aims are to review the literature findings on the clinical outcomes of VATS sympathectomy for long QT and present a local centre case report on the outcomes of T2-T5 sympathectomy. METHODS: Relevant articles were identified by a systematic search of PubMed, Cochrane and Scopus databases, from November 1985 to October 2015. A total of 520 patients from 21 publications were included for analysis and discussion in three main areas: presenting symptoms and indication for surgery, perioperative complications, and patient quality of life following surgery. Our case study reviews a 49-year-old female with recently diagnosed long QT syndrome and intolerance to beta blocker therapy successfully managed with T2-T5 thoracic sympathectomy. RESULTS: The most common presenting indication for operative management of long QT syndrome was syncope (208/520 patients) and tachyarrhythmia (207/520 patients). T1-T5 left sympathectomy was performed in 15/21 published reports (332/520 patients) with partial stellate removal or in its entirety. Follow-up of patients ranged from 1 month to 11 years. Four patients died in the postoperative period, from fatal arrhythmias. The most common postoperative findings were no symptoms (64/520 patients); tachyarrhythmia (55/520 patients), syncope (45/520 patients), and Horner's syndrome (13/520 patients with 27 patients reporting associated symptoms). Thirteen cases reported on the QTc changes post sympathectomy and 9/13 cases involving 220/520 patients showed marked QTc reduction following surgery. Mean preoperative QTc was 558ms and median 559ms. Mean postoperative QTc was 476ms and median 466ms. Our patient showed a marked reduction in QTc following surgery, with no evidence of arrhythmias and reduced beta blocker dependence. CONCLUSIONS: Surgical management of LQTS has historically involved a left cervicothoracic stellectomy removing stellate ganglia and typically part of the left thoracic sympathetic chain resulting in reduction in symptoms but increasing the risk of Horner's syndrome and intermittent temperature changes [4,5]. Surgical resection of the thoracic ganglia alone for management of LQTS is scarce in the literature. Short-term follow-up in our case study following a T2-T5 sympathectomy revealed reduction in symptoms, no requirement for beta blocker therapy and reduced QTc interval. Further follow-up using greater patient numbers will further support T2-T5 sympathectomy as an option for surgical management of LQTS.

Video-assisted thoracoscopic left cardiac sympathetic denervation for congenital long QT syndrome.

Left cardiac sympathetic denervation is an effective therapy for patients with congenital long QT syndrome resistant to beta-blocker therapy. In this video tutorial we describe a minimally invasive video-assisted thoracoscopic technique for performing left cardiac sympathetic denervation.

Video-Assisted Thoracoscopic Left Cardiac Sympathetic Denervation in Chinese Patients with Long QT Syndrome.

Long QT syndrome is a rare but potentially lethal cardiac channelopathy. The primary aim of the study was to investigate the long-term effects of video-assisted thoracoscopic (VATS) left cardiac sympathetic denervation (LCSD) in Chinese patients with long QT syndrome.VATS-LCSD was performed in eight Chinese patients with LQTS. Twelve-lead ECGs and 24-hour Holter monitoring ECGs were recorded before and after surgery. The medical charts were reviewed to obtain patient data, and the patients who had been lost to follow-up were contacted through telephone.The average QTc was shortened from 534 ± 52.7 to 503 ± 43.7 ms (P = 0.030) 24 hours post-surgery and down to 486 ± 34.8 ms (P = 0.021) 1 week post-surgery, with the heart rate unchanged. The average QT dispersion was reduced from 67 ± 17.5 to 21 ± 3.9 ms (P < 0.001) 24 hours post-surgery and remained shortened 1 week later (30 ± 8.1 ms, P < 0.001). Moreover, the 24-hour ECG showed that the QTc was shortened from 552 ± 95.9 to 497 ± 19.7 ms at the minimum heart rate (P = 0.008), and was decreased from 594 ± 144 to 495 ± 74.1 ms at the maximum heart rate (P= 0.04), while the minimum and maximum heart rates were comparable before and after surgery. No death was observed during the follow-up period and the clinical symptoms improved in all patients. The annual event rate decreased from 4 ± 3.50 to 0.63 ± 1.37 events/year (P = 0.034) after surgery.These findings indicate that LCSD shortens the QTc, with the heart rate remaining unchanged. QTd might be a useful parameter for evaluating the efficacy of VATS-LCSD. LCSD could improve patients' life quality by reducing cardiac events.

Cardiac transplantation in children and adolescents with long QT syndrome.

BACKGROUND: Long QT syndrome (LQTS) is a potentially lethal, yet highly treatable, cardiac channelopathy. Cardiac transplantation has been reported anecdotally for patients with severe LQTS refractory to standard therapies. OBJECTIVE: The purpose of this study was to evaluate the incidence of and risk factors for cardiac transplantation in children evaluated and treated in an LQTS specialty center. METHODS: This was a retrospective review of 349 children with LQTS (mean age at diagnosis, 8.0 ± 5.7 years; mean corrected QT interval, 469 ± 51 ms; long QT syndrome type 1 [LQT1] in 46%, LQT2 in 31%, and LQT3 in 9%) evaluated from 2000 to 2013. A subset analysis was performed on patients referred for cardiac transplantation. RESULTS: Only 3 patients (0.9%; all LQT3; 2 female) underwent cardiac transplantation at ages 4, 11, and 17 years. Overall, 90 of 349 (26%) were symptomatic (exhibited LQTS-associated cardiac events) before LQTS diagnosis, including those who ultimately underwent transplant. Age at sentinel event was associated with transplantation (3 of 26 [12%] with an event at <1 year of life were transplanted vs 0 of 64 with an event after age 1; P = .02). Genotype was also a risk factor (3 of 32 patients with LQT3 were transplanted [9.4%] vs 0 of 270 patients with LQT1 or LQT2; P = .001). Before transplant, all patients had recurrent ventricular fibrillation-terminating shocks despite combination drug therapy and bilateral sympathetic denervation. All transplanted patients are alive at follow-up. CONCLUSION: Cardiac transplantation is seldom necessary for the management of LQTS. However, patients with LQT3 and in utero/neonatal expressivity are at higher risk of treatment failure and refractory ventricular arrhythmias with standard therapy, and cardiac transplantation should be considered for this malignant subset of LQTS.

Video-Assisted Thoracoscopic Left Cardiac Sympathetic Denervation in Patients with Hereditary Ventricular Arrhythmias.

BACKGROUND: Left cardiac sympathetic denervation (LCSD) has been underutilized in patients with hereditary ventricular arrhythmia syndromes such as congenital long QT syndrome (LQTS) and catecholaminergic polymorphic ventricular tachycardia (CPVT). The purpose of this study was to investigate the safety and efficacy of video-assisted thoracoscopic (VATS) LCSD in such patients. METHODS: Fifteen patients (four men, 24.6 ± 10.5 years old) who underwent VATS-LCSD between November 2010 and January 2015 for hereditary ventricular arrhythmia syndromes at Kyungpook National University Hospital were enrolled in this study. The safety and efficacy of VATS-LCSD were evaluated by periprocedural epinephrine tests and assessing the development of complications and cardiac events during follow-up. RESULTS: Fourteen patients with LQTS and one patient with CPVT underwent VATS-LCSD. Six and one patients developed ventricular tachyarrhythmia during preprocedural and postprocedural epinephrine test, respectively (P = 0.063). No serious complications such as Horner syndrome, pneumothorax, or bleeding developed after LCSD. Mean hospital stay after VATS-LCSD was 3.7 ± 1.5 days. During a mean follow-up of 927 ± 350 days, one LQTS patient and one CPVT patient, neither of whom manifested tachyarrhythmia during post-LCSD epinephrine test, developed torsades de pointes and syncope, respectively. The annual event rates of six patients who were symptomatic during the period preceding LCSD decreased from 0.97 to 0.19 events/year (P = 0.045). CONCLUSIONS: VATS-LCSD was a safe, and effective procedure for patients with hereditary ventricular tachycardia syndrome, with no serious adverse events and with short hospital stay.

Quality of life after videoscopic left cardiac sympathetic denervation in patients with potentially life-threatening cardiac channelopathies/cardiomyopathies.

BACKGROUND: Left cardiac sympathetic denervation (LCSD) provides an additive or potentially alternative treatment option for patients with life-threatening cardiac channelopathies/cardiomyopathies. OBJECTIVE: We sought to examine the effects of LCSD on quality of life (QOL). METHODS: From November 2005 to May 2013, 109 patients who underwent LCSD were subsequently sent postoperative QOL surveys. RESULTS: Of 109 patients, 8 (7%) could not be contacted. Of the remaining 101 patients, 62 returned surveys (response rate 61%). There were an average of 4.1 ± 1.8 self-reported side effects immediately after LCSD. The most common anticipated side effects included unilateral hand dryness, color or temperature variance between sides of the face, and abnormal sweating. Although parent-reported pediatric physical QOL scores were lower than national norms, there were no differences in psychosocial QOL or disability scores (P = .09 and .33, respectively). QOL scores for adult patients were not significantly different from a US normative sample. Adult LCSD patients reported less disability than a US normative sample (P < .01). There was no correlation between QOL scores and the presence of anticipated side effects. However, among the subset of pediatric patients who continued to receive ventricular fibrillation-terminating implantable cardioverter-defibrillator shocks after LCSD, there was a correlation between their disability scores and the number of reported shocks (Spearman correlation = 0.56). The majority of patients/parents reported that they were very or somewhat satisfied with their surgery (or their child's surgery) and would definitely or probably recommend LCSD to another patient. CONCLUSION: Despite the anticipated side effects associated with LCSD, patients are satisfied with their surgery and indicate that they would recommend the surgery to another patient.

Physical and Psychological Consequences of Left Cardiac Sympathetic Denervation in Long-QT Syndrome and Catecholaminergic Polymorphic Ventricular Tachycardia.

BACKGROUND: Left cardiac sympathetic denervation reduces risk in long-QT syndrome (LQTS) and catecholaminergic polymorphic ventricular tachycardia. Side effects and patient satisfaction have not been systematically analyzed in patients who underwent left cardiac sympathetic denervation. Aims of this study included documenting physical and psychological consequences and patient satisfaction after left cardiac sympathetic denervation in LQTS or catecholaminergic polymorphic ventricular tachycardia. METHODS AND RESULTS: Patients with LQTS (N=40) and catecholaminergic polymorphic ventricular tachycardia (N=7) underwent video-assisted thoracoscopic left cardiac sympathetic denervation, with a median follow-up of 29 months (range, 1-67 months). Clinical records were reviewed; 44 patients completed a telephone survey. Of 47 patients (53%), 25 were preoperatively symptomatic (15 syncope, 7 near-drowning, and 3 resuscitated sudden death). Indications for left cardiac sympathetic denervation included ß-blocker intolerance (15; 32%) or nonadherence (10; 21%) and disease factors (18; 38%; catecholaminergic polymorphic ventricular tachycardia [6], near-drowning [2], exertional syncope [1], symptoms on therapy [2], LQT3 [1], QTc>520 ms [6]). Other indications were competitive sports participation (2), family history of sudden death (1), and other (1). Median QTc did not change among patients with LQTS (461±60 to 476±54 ms; P=0.49). Side effects were reported by 42 of 44 (95%). Twenty-nine patients (66%) reported dryness on left side, 26 (59%) a Harlequin-type (unilateral) facial flush, 24 (55%) contralateral hyperhidrosis, 17 (39%) differential hand temperatures, 5 (11%) permanent and 4 (9%) transient ptosis, 5 (11%) thermoregulation difficulties, 4 (9%) a sensation of left arm paresthesia, and 3 (7%) sympathetic flight/fright response loss. Majority of the patients were satisfied postoperatively: 38 (86%) were happy with the procedure, 33 (75%) felt safer, 40 (91%) recommended the procedure to others, and 40 (91%) felt happy with their scar appearance. CONCLUSIONS: Despite significant morbidity resulting from left cardiac sympathetic denervation, patients with LQTS and CPVT have high levels of postoperative satisfaction.

The effect of esmolol on corrected-QT interval, corrected-QT interval dispersion changes seen during anesthesia induction in hypertensive patients taking an angiotensin-converting enzyme inhibitor / Efeito de esmolol sobre o intervalo QT corrigido e alterações da dispersão do intervalo QT corrigido observadas durante a indução da anestesia em pacientes hipertensos que receberam um inibidor da enzima conversora de angiotensina / Efecto del esmolol sobre el intervalo QT corregido y alteraciones de la dispersión del intervalo QT corregido observadas durante la inducción de la anestesia en pacientes hipertensos que recibieron un inhibidor de la enzima convertidora de la angiotensina

BACKGROUND AND OBJECTIVES: The importance of minimizing the exaggerated sympatho-adrenergic responses and QT interval and QT interval dispersion changes that may develop due to laryngoscopy and tracheal intubation during anesthesia induction in the hypertensive patients is clear. Esmolol decreases the hemodynamic response to laryngoscopy and intubation. However, the effect of esmolol in decreasing the prolonged QT interval and QT interval dispersion as induced by laryngoscopy and intubation is controversial. We investigated the effect of esmolol on the hemodynamic, and corrected-QT interval and corrected-QT interval dispersion changes seen during anesthesia induction in hypertensive patients using angiotensin converting enzyme inhibitors. METHODS: 60 ASA I-II patients, with essential hypertension using angiotensin converting enzyme inhibitors were included in the study. The esmolol group received esmolol at a bolus dose of 500 mcg/kg followed by a 100 mcg/kg/min infusion which continued until the 4th min after intubation. The control group received 0.9% saline similar to the esmolol group. The mean blood pressure, heart rate values and the electrocardiogram records were obtained as baseline values before the anesthesia, 5 min after esmolol and saline administration, 3 min after the induction and 30 s, 2 min and 4 min after intubation. RESULTS: The corrected-QT interval was shorter in the esmolol group (p = 0.012), the corrected-QT interval dispersion interval was longer in the control group (p = 0.034) and the mean heart rate was higher in the control group (p = 0.022) 30 s after intubation. The risk of arrhythmia frequency was higher in the control group in the 4-min period following intubation (p = 0.038). CONCLUSION: Endotracheal intubation was found to prolong corrected-QT interval and corrected-QT interval dispersion, and increase the heart rate during anesthesia induction with propofol in hypertensive patients using angiotensin ...

JUSTIFICATIVA E OBJETIVO: É óbvia a importância de minimizar as respostas simpatoadrenérgicas exageradas e o intervalo QT e a dispersão do intervalo QT que podem ocorrer por causa de laringoscopia e intubação traqueal durante a indução da anestesia em pacientes hipertensos. Esmolol diminui a resposta hemodinâmica à laringoscopia e à intubação. Porém, o efeito de esmolol sobre a redução do intervalo QT prolongado e a dispersão do intervalo QT induzida pela laringoscopia e intubação é controverso. Pesquisamos o efeito de esmolol sobre a hemodinâmica e o intervalo QT corrigido e as alterações da dispersão do intervalo QT observadas durante a indução da anestesia em pacientes hipertensos que receberam inibidores da enzima conversora de angiotensina (IECA). MÉTODOS: Foram incluídos no estudo 60 pacientes, estado físico ASA I-II, com hipertensão arterial essencial e que receberam IECA. O grupo esmolol recebeu uma dose em bolus de 500 mcg kg-1, seguida por infusão contínua de 100 mcg kg-1 min-1 até o quarto minuto após a intubação. O grupo controle recebeu solução salina a 0,9%, semelhantemente ao grupo esmolol. Os valores da pressão arterial média e da frequência cardíaca e os registros do eletrocardiograma foram obtidos durante a fase inicial pré-anestesia, cinco minutos após a administração de esmolol e solução salina, três minutos após a indução e 30 segundos, dois minutos e quatro minutos após a intubação. RESULTADOS: O intervalo QT corrigido foi menor no grupo esmolol (p = 0,012), o intervalo de dispersão do intervalo QT corrigido foi maior no grupo controle (p = 0,034) e a frequência cardíaca média foi maior no grupo controle (p = 0,022) 30 segundos após a intubação. O risco da frequência de arritmia foi maior no grupo controle no quarto minuto após a intubação (p = 0,038). CONCLUSÃO: Descobrimos que a intubação traqueal prolonga o intervalo e a dispersão do intervalo QT corrigido e aumenta a frequência cardíaca durante a indução da ...

JUSTIFICACIÓN Y OBJETIVO: Es evidente la importancia que tiene minimizar las respuestas simpatoadrenérgicas exageradas y el intervalo QT y la dispersión del intervalo QT que pueden ocurrir a causa de la laringoscopia e intubación traqueal durante la inducción de la anestesia en pacientes hipertensos. El esmolol disminuye la respuesta hemodinámica a la laringoscopia y a la intubación. Sin embargo, su efecto sobre la reducción del intervalo QT prolongado y la dispersión del intervalo QT inducida por la laringoscopia e intubación es controvertido. Investigamos el efecto del esmolol sobre la hemodinámica y el intervalo QT corregido, y las alteraciones de la dispersión del intervalo QT observadas durante la inducción de la anestesia en pacientes hipertensos que recibieron inhibidores de la enzima convertidora de la angiotensina. MÉTODOS: Fueron incluidos en el estudio 60 pacientes, estado físico ASA I-II, con hipertensión arterial esencial y que recibieron inhibidores de la enzima convertidora de la angiotensina. El grupo esmolol recibió una dosis en bolos de 500 mcg/kg, seguida de infusión continua de 100 mcg/kg/min hasta el cuarto minuto después de la intubación. El grupo control recibió una solución salina al 0,9%, de forma similar al grupo esmolol. Los valores de la presión arterial media y de la frecuencia cardíaca y los registros del electrocardiograma fueron obtenidos durante la fase inicial preanestésica, 5 min después de la administración del esmolol y la solución salina, 3 min después de la inducción, y 30 s, 2 min y 4 min después de la intubación. RESULTADOS: El intervalo QT corregido fue menor en el grupo esmolol (p = 0,012), el intervalo de dispersión del intervalo QT corregido fue mayor en el grupo control (p = 0,034) y la frecuencia cardíaca media fue mayor en el grupo control (p = 0,022) 30 s después de la intubación. El riesgo de la frecuencia de arritmia fue mayor en el grupo control en el cuarto minuto después de la intubación ...

Effects on repolarization using dynamic QT interval monitoring in long-QT patients following left cardiac sympathetic denervation.

BACKGROUND: Videoscopic left cardiac sympathetic denervation (LCSD) is an adjunct therapy for reduction of arrhythmia-induced events in patients with long-QT syndrome (LQTS). LCSD reduces LQTS-triggered breakthrough cardiac events. The temporal effects of QTc changes post-LCSD have not been studied. METHODS: We utilized continuous QTc monitoring on 72 patients with LQTS. We evaluated acute and long-term QTc changes in comparison to 12-lead ECG-derived QTc values prior to surgery, 24 hours postsurgery, and at follow up ≥3 months. RESULTS: Seventy-two patients underwent LCSD at our institution (46% male, mean age at LCSD was 14 ± 10 years). The mean baseline, pre-LCSD QTc was 505 ± 56 ms, which had decreased significantly at ≥3 months post-LCSD to 491 ± 40 ms (P = 0.001). QTc monitoring revealed that the majority of the cohort (53/72; 74%) had a transient increase >30 ms in QTc from baseline, with an average maximum increase of 72 ± 30 ms. Resolution within 10 ms of baseline or less occurred in 57% (30/53) at 24 hours post-LCSD. CONCLUSIONS: Although LQTS patients may have a paradoxically increased QTc post-LCSD, the effects are transient in most patients. Importantly, no patients experienced any arrhythmias in the postoperative setting related to this transient rise in QTc.

Surgical cardiac denervation therapy for treatment of congenital ion channelopathies in pediatric patients: a contemporary, single institutional experience.

BACKGROUND: Congenital ion channel disorders, including congenital long QT syndrome (LQTS), cause significant morbidity in pediatric patients. When medication therapy does not control symptoms or arrhythmias, more invasive treatment strategies may be necessary. This study examines our institution's clinical experience with surgical cardiac denervation therapy for management of these arrhythmogenic disorders in children. METHODS: An institutional review board-approved retrospective review identified ten pediatric patients with congenital ion channelopathies who underwent surgical cardiac denervation therapy at a single institution between May 2011 and April 2014. Eight patients had a diagnosis of congenital LQTS, two patients were diagnosed with catecholaminergic polymorphic ventricular tachycardia (CPVT). All patients underwent sympathectomy and partial stellate ganglionectomy via video-assisted thoracoscopic surgery (VATS). RESULTS: Six of the ten patients had documented ventricular arrhythmias preoperatively, and 70% of the patients had preoperative syncope. The corrected QT interval decreased in 75% of patients with LQTS following sympathectomy. Postoperative arrhythmogenic symptoms were absent in 88% of congenital LQTS patients, but both patients with CPVT continued to have symptoms throughout the duration of follow-up. All patients were alive after a median follow-up period of 10 months. CONCLUSIONS: Surgical cardiac denervation therapy via VATS is a useful treatment strategy for congenital LQTS patients who fail medical management, and its potential benefit in the management of CPVT is unclear. A prospective comparison of the efficacy of surgical cardiac denervation therapy and implantable cardioverter-defibrillator use in congenital ion channelopathies is timely and crucial.

The safety of modern anesthesia for children with long QT syndrome.

BACKGROUND: Patients with long QT syndrome (LQTS) may experience a clinical spectrum of symptoms, ranging from asymptomatic, through presyncope, syncope, and aborted cardiac arrest, to sudden cardiac death. Arrhythmias in LQTS are often precipitated by autonomic changes. This patient population is believed to be at high risk for perioperative arrhythmia, specifically torsades de pointes (TdP), although this perception is largely based on limited literature that predates current anesthetic drugs and standards of perioperative monitoring. We present the largest multicenter review to date of anesthetic management in children with LQTS. METHODS: We conducted a multicentered retrospective chart review of perioperative management of children with clinically diagnosed LQTS, aged 18 years or younger, who received general anesthesia (GA) between January 2005 and January 2010. Data from 8 institutions were collated in an anonymized database. RESULTS: One hundred three patients with LQTS underwent a total of 158 episodes of GA. The median (interquartile range) age and weight of the patients at the time of GA was 9 (3-15) years and 30.3 (15.4-54) kg, respectively. Surgery was LQTS-related in 81 (51%) GA episodes (including pacemaker, implantable cardioverter-defibrillator, and loop recorder insertions and revisions and lead extractions) and incidental in 77 (49%). ß-blocker therapy was administered to 76% of patients on the day of surgery and 47% received sedative premedication. Nineteen percent of patients received total IV anesthesia, 30% received total inhaled anesthesia, and the remaining 51% received a combination. No patient received droperidol. There were 5 perioperative episodes of TdP, all in neonates or infants, all in surgery that was LQTS-related, and none of which was overtly attributable to anesthetic regimen. Thus the incidence (95% confidence interval) of perioperative TdP in incidental versus LQTS-related surgery was 0/77 (0%; 0%-5%) vs 5/81 (6.2%; 2%-14%). CONCLUSIONS: With optimized perioperative management, modern anesthesia for incidental surgery in patients with LQTS is safer than anecdotal case report literature might suggest. Our series suggests that the risk of perioperative TdP is concentrated in neonates and infants requiring urgent interventions after failed first-line management of LQTS.

Left thoracoscopic sympathectomy for cardiac denervation in patients with life-threatening ventricular arrhythmias.

BACKGROUND: We reported the outcomes of a single-institution experience using video-assisted thoracoscopic left cardiac sympathetic denervation as an adjunctive therapeutic technique in pediatric and young adult patients with life-threatening ventricular arrhythmias. METHODS: We conducted a retrospective clinical review of all patients who underwent left cardiac sympathetic denervation by means of video-assisted thoracoscopic surgery at our institution. From August 2000 to December 2011, 24 patients (13 with long QT syndrome, 9 with catecholaminergic polymorphic ventricular tachycardia, and 2 with idiopathic ventricular tachycardia) were identified from the cardiology database and surgical records. RESULTS: There were no intraoperative complications. The median postoperative length of stay was 2 days (range, 1-32 days). There were no major perioperative complications. Longer-term follow-up was available in 22 of 24 patients at a median follow-up of 28 months (range, 4-131 months). Sixteen (73%) of the 22 patients experienced a marked reduction in their arrhythmia burden, with 12 (55%) becoming completely arrhythmia free after sympathectomy. Six (27%) of the patients were nonresponsive to treatment; each had persistent symptoms at follow-up. CONCLUSIONS: Video-assisted thoracoscopic left cardiac sympathetic denervation can be safely and effectively performed in most patients with life-threatening ventricular arrhythmias. This minimally invasive procedure is a promising adjunctive therapeutic option that achieves a beneficial response in most symptomatic patients. These results support the inclusion of thoracoscopic cardiac sympathetic denervation among the treatment armamentarium in all patients with ventricular arrhythmias refractive to conventional medical therapy.