Implantable cardioverter defibrillator use in arrhythmogenic right ventricular cardiomyopathy in North America and Europe.

BACKGROUND AND AIMS: Implantable cardioverter-defibrillators (ICDs) are critical for preventing sudden cardiac death (SCD) in arrhythmogenic right ventricular cardiomyopathy (ARVC). This study aims to identify cross-continental differences in utilization of primary prevention ICDs and survival free from sustained ventricular arrhythmia (VA) in ARVC. METHODS: This was a retrospective analysis of ARVC patients without prior VA enrolled in clinical registries from 11 countries throughout Europe and North America. Patients were classified according to whether they received treatment in North America or Europe and were further stratified by baseline predicted VA risk into low- (<10%/5 years), intermediate- (10%-25%/5 years), and high-risk (>25%/5 years) groups. Differences in ICD implantation and survival free from sustained VA events (including appropriate ICD therapy) were assessed. RESULTS: One thousand ninety-eight patients were followed for a median of 5.1 years; 554 (50.5%) received a primary prevention ICD, and 286 (26.0%) experienced a first VA event. After adjusting for baseline risk factors, North Americans were more than three times as likely to receive ICDs {hazard ratio (HR) 3.1 [95% confidence interval (CI) 2.5, 3.8]} but had only mildly increased risk for incident sustained VA [HR 1.4 (95% CI 1.1, 1.8)]. North Americans without ICDs were at higher risk for incident sustained VA [HR 2.1 (95% CI 1.3, 3.4)] than Europeans. CONCLUSIONS: North American ARVC patients were substantially more likely than Europeans to receive primary prevention ICDs across all arrhythmic risk strata. A lower rate of ICD implantation in Europe was not associated with a higher rate of VA events in those without ICDs.

ß-blocker adherence among patients with congenital long QT syndrome: a nationwide study.

AIM: ß-blockers are the first line of treatment in patients with congenital long QT syndrome (cLQTS) (class I or II recommendation) in order to prevent malignant arrhythmias. Hence, we examined long-term ß-blocker adherence and associated risk factors among patients with cLQTS. METHODS AND RESULTS: Danish patients with cLQTS claiming a prescription for any ß-blocker after their cLQTS diagnosis were identified using data from nationwide registries and specialized inherited cardiac disease clinics (1995-2017). Patients were followed for up to 5 years. Treatment breaks >60 days were assessed (i.e. proxy for reduced adherence). Multivariable Cox regression was used to identify risk factors associated with breaks of >60 days in ß-blocker treatment. Overall, 500 out of 633 (79%) patients with cLQTS claimed at least one prescription for any ß-blocker after cLQTS diagnosis. During follow-up, 38.4% had a treatment break. Risk factors significantly associated with treatment breaks were implantable cardioverter defibrillator (ICD) [hazard ratio (HR) = 1.65, 95% confidence interval (CI): 1.08-2.53], ß-blocker side effects (HR = 2.69, 95% CI: 1.75-4.13), and psychiatric disease (HR = 1.63, 95% CI: 1.04-2.57). In contrast, patients presenting with ventricular tachycardia/syncope as cLQTS disease manifestation were less likely to have a treatment break compared with asymptomatic patients (HR = 0.55, 95% CI: 0.33-0.92). CONCLUSION: Reduced ß-blocker adherence was common with more than a third of patients having a treatment break >60 days after cLQTS diagnosis. Patients with psychiatric disease, self-reported ß-blocker side effects, and an ICD were more likely to display reduced adherence, whereas a severe cLQTS disease manifestation was associated with optimal ß-blocker adherence.

Complications of implantable cardioverter-defibrillator treatment in arrhythmogenic right ventricular cardiomyopathy.

AIMS: Treatment with implantable cardioverter-defibrillators (ICD) is a cornerstone for prevention of sudden cardiac death in arrhythmogenic right ventricular cardiomyopathy (ARVC). We aimed at describing the complications associated with ICD treatment in a multinational cohort with long-term follow-up. METHODS AND RESULTS: The Nordic ARVC registry was established in 2010 and encompasses a large multinational cohort of ARVC patients, including their clinical characteristics, treatment, and events during follow-up. We included 299 patients (66% males, median age 41 years). During a median follow-up of 10.6 years, 124 (41%) patients experienced appropriate ICD shock therapy, 28 (9%) experienced inappropriate shocks, 82 (27%) had a complication requiring surgery (mainly lead-related, n = 75), and 99 (33%) patients experienced the combined endpoint of either an inappropriate shock or a surgical complication. The crude rate of first inappropriate shock was 3.4% during the first year after implantation but decreased after the first year and plateaued over time. Contrary, the risk of a complication requiring surgery was 5.5% the first year and remained high throughout the study period. The combined risk of any complication was 7.9% the first year. In multivariate cox regression, presence of atrial fibrillation/flutter was a risk factor for inappropriate shock (P < 0.05), whereas sex, age at implant, and device type were not (all P > 0.05). CONCLUSION: Forty-one percent of ARVC patients treated with ICD experienced potentially life-saving ICD therapy during long-term follow-up. A third of the patients experienced a complication during follow-up with lead-related complications constituting the vast majority.

Pregnancies, ventricular arrhythmias, and substrate progression in women with arrhythmogenic right ventricular cardiomyopathy in the Nordic ARVC Registry.

AIMS: Women with arrhythmogenic right ventricular cardiomyopathy (ARVC) are at relatively lower risk of ventricular arrhythmias (VAs) than men, but the physical burden associated with pregnancy on VA risk remains insufficiently studied. We aimed to assess the risk of VA in relation to pregnancies in women with ARVC. METHODS AND RESULTS: We included 199 females with definite ARVC (n = 121) and mutation-positive family members without ascertained ARVC diagnosis (n = 78), of whom 120 had at least one childbirth. Ventricular arrhythmia-free survival after the latest childbirth was compared between women with one (n = 20), two (n = 67), and three or more (n = 37) childbirths. Cumulative probability of VA for each pregnancy (n = 261) was assessed from conception through 2 years after childbirth and compared between those pregnancies that occurred before (n = 191) or after (n = 19) ARVC diagnosis and in mutation-positive family members (n = 51). The nulliparous women had lower median age at ARVC diagnosis (38 vs. 42 years, P < 0.001) and first VA (22 vs. 41 years, P < 0.001). Ventricular arrhythmia-free survival after the latest childbirth was not related to the number of pregnancies. No pregnancy-related VA was reported among the family members. Women who gave birth after ARVC diagnosis had elevated risk of VA postpartum (hazard ratio 13.74, 95% confidence interval 2.9-63, P = 0.001), though only two events occurred during pregnancies. CONCLUSION: In women with ARVC, pregnancy was uneventful for the overwhelming majority and the number of prior completed pregnancies was not associated with VA risk. Pregnancy-related VA was primarily related to the phenotypical severity rather than pregnancy itself.

An Exploratory Analysis of Proprotein Convertase Subtilisin/Kexin Type 9 Inhibition and Aortic Stenosis in the FOURIER Trial.

Importance: Despite recent advances in treatment of severe aortic valve stenosis (AS), AS remains a life-threatening condition with no proven disease-modifying therapy. Low-density lipoprotein cholesterol (LDL-C) and lipoprotein(a) (Lp[a]) have been implicated in the pathobiology of AS. The proprotein convertase subtilisin/kexin type 9 inhibitor evolocumab reduces circulating LDL-C concentrations by 50% to 60% and Lp(a) by 20% to 30%. Objective: To determine whether evolocumab reduces the risk of AS events in patients with atherosclerotic cardiovascular disease. Interventions: Patients were randomized 1:1 to evolocumab or placebo. Design, Setting, and Participants: Exploratory analysis of the FOURIER trial, which enrolled 27 564 patients with stable atherosclerotic cardiovascular disease who were taking statin therapy at 1242 sites in 49 countries from February 2013 to November 2016. Patients were randomized to evolocumab or placebo and followed up for a median (interquartile range) of 2.2 (1.8-2.5) years. This post hoc analysis was performed from September 2019 to February 2020. Main Outcomes and Measures: Site-reported adverse events of new or worsening AS or aortic valve replacement (termed AS events). The adjusted risk of AS events was calculated with a multivariable model including concentrations of Lp(a) and LDL-C corrected for Lp(a) content, plus age, sex, diabetes, hypertension, current smoking, and estimated glomerular filtration rate. Evolocumab efficacy was tested using a Cox proportional hazards model. Results: Aortic stenosis events occurred in 63 patients (48 men [76%]; mean [SD] age, 69 [9] years) over a median of 2.2 years. Elevated Lp(a) concentration was associated with higher rates of AS events (adjusted hazard ratio [aHR], 1.55 [95% CI, 1.17-2.05] per SD; P = .002), including aortic valve replacement (aHR, 2.22 [95% CI, 1.38-3.58] per SD; P = .001), after multivariable adjustment. The corrected LDL-C concentration was not significantly associated with AS events (aHR, 1.23 [95% CI, 0.93-1.61] per SD; P = .14). The overall HR for AS events with evolocumab was 0.66 (95% CI, 0.40-1.09), with no apparent association in the first year (HR, 1.09 [95% CI, 0.48-2.47]) but an HR of 0.48 (95% CI, 0.25-0.93) after the first year of treatment. Conclusions and Relevance: In this exploratory analysis of the FOURIER trial, higher Lp(a) levels, but not Lp(a)-corrected LDL-C levels, were associated with a higher risk of subsequent AS events, including aortic valve replacement. Long-term therapy with evolocumab may reduce AS events, and this raises the possibility that specific pharmacologic lipid-lowering therapy could offer a means to prevent or slow the progression of AS. These exploratory findings merit further investigation with a dedicated randomized clinical trial. Trial Registration: ClinicalTrials.gov Identifier: NCT01764633.

Endoscopic ultrasound-guided pleural biopsy in the hands of the pulmonologist.

The use of the endobronchial ultrasound (EBUS) endoscope in the oesophagus, the so-called EUS-B procedure, for the diagnosis and staging of thoracic malignancy is quickly gaining ground. Pleural lesions located close to the oesophagus can be inaccessible to transthoracic biopsy and endoscopic procedures can be the only option. We here present two cases demonstrating that EUS-B-guided fine needle aspiration (EUS-B-FNA) of pleural lesions is possible. The first case demonstrates a EUS-B-FNA with malignant mesothelioma of a pleural lesion in a 70-year-old patient. In the second case, EUS-B-FNA diagnosed a pleural metastasis from adenoid cystic adenocarcinoma in a 75-year-old-patient. In conclusion, we hereby demonstrate that EUS-B-FNA from pleural lesions is feasible and appears to be safe.

Incidence, Predictors, and Success of Ventricular Tachycardia Catheter Ablation in Arrhythmogenic Right Ventricular Cardiomyopathy (from the Nordic ARVC Registry).

Catheter ablation may reduce ventricular tachycardia (VT) burden in arrhythmogenic right ventricular cardiomyopathy (ARVC) patients. However, little is known about factors predicting need for ablation. Therefore, we sought to investigate predictors and use of VT ablation and to evaluate the postprocedural outcome in ARVC patients. We studied 435 patients from the Nordic ARVC registry including 220 probands with definite ARVC according to the 2010 task force criteria and 215 mutation-carrying relatives identified through cascade screening. Patients were followed until first-time VT ablation, death, heart transplantation, or January 1st 2018. Additionally, patients undergoing VT ablation were further followed from the time of ablation for recurrent ventricular arrhythmias. The cumulative use of VT ablation was 4% (95% confidence interval [CI] 3% to 6%) and 11% (95% CI 8% to 15%) after 1 and 10 years. All procedures were performed in probands in whom cumulative use was 8% (95% CI 5% to 12%) and 20% (95% CI 15% to 26%). In adjusted analyses among probands, only young age predicted ablation. In patients undergoing ablation, risk of recurrent arrhythmias was 59% (95% CI 44% to 71%) and 74% (95% CI 59% to 84%) 1 and 5 years after the procedure. Despite high recurrence rates, the burden of ventricular arrhythmias was reduced after ablation (p = 0.0042). Young age, use of several antiarrhythmic drugs and inducibility to VT after ablation were associated with an unfavorable outcome. In conclusion, twenty percent of ARVC probands developed a clinical indication for VT ablation within 10 years whereas mutation-carrying relatives were without such need. Although the burden of ventricular arrhythmias decreased after ablation, risk of recurrence was substantial.

Atrial fibrillation as a clinical characteristic of arrhythmogenic right ventricular cardiomyopathy: Experience from the Nordic ARVC Registry.

BACKGROUND: Recent studies in arrhythmogenic right ventricular cardiomyopathy (ARVC) patients have drawn attention to atrial fibrillation (AF) as an arrhythmic manifestation of ARVC and as an indicator of atrial involvement in the disease progression. We aimed to assess the prevalence of AF in the Scandinavian cohort of ARVC patients and to evaluate its association with disease clinical manifestations. METHODS: Study sample comprised of 293 definite ARVC patients by 2010 Task Force criteria (TFC2010) and 141 genotype-positive family members (total n = 434, 43% females, median age at ARVC diagnosis 41 years [interquartile range (IQR) 28-52 years]). ARVC diagnostic score was calculated as the sum of major (2 points) and minor (1 point) criteria in all categories of the TFC2010. RESULTS: AF was diagnosed in 42 patients (10%): in 41 patients with definite ARVC diagnosis (14%) vs in one genotype-positive family member (1%), p < 0.001. The median age at AF onset was 51 (IQR 38-58) years. The prevalence of AF was related to the ARVC diagnostic score: it significantly increased starting with the diagnostic score 4 (2% in those with score 3 vs 13% in those with score 4, p = 0.023) and increased further with increased diagnostic score (Somer's d value is 0.074, p < 0.001). CONCLUSION: AF is seen in 14% of definite ARVC patients and is related to the severity of disease phenotype thus suggesting AF being an arrhythmic manifestation of this cardiomyopathy indicating atrial myocardial involvement in the disease progression.

Aetiologies and temporal trends of atrioventricular block in young patients: a 20-year nationwide study.

AIMS: To describe aetiologies and temporal trends in young patients with atrioventricular block (AVB). METHODS AND RESULTS: We identified all patients in Denmark, receiving their first pacemaker because of AVB before the age of 50 years between 1996 and 2015. Medical records were reviewed and clinical information and diagnostic work-up results were obtained to evaluate the aetiology. We used Poisson regression testing for temporal trends. One thousand and twenty-seven patients were identified, median age at time of implantation was 38 (interquartile range 25-45) years, 584 (56.9%) were male. The aetiologies were complications to cardiac surgery [n = 157 (15.3%)], congenital AVB [n = 93 (9.0%)], cardioinhibitory reflex [n = 52 (5.0%)], congenital heart disease [n = 43 (4.2%)], complication to radiofrequency ablation [n = 35 (3.4%)], cardiomyopathy [n = 31 (3.0%)], endocarditis [n = 18 (1.7%)], muscular dystrophy [n = 14 (1.4%)], ischaemic heart disease [n = 14 (1.4%)], sarcoidosis [n = 11 (1.1%)], borreliosis [n = 9 (0.9%)], hereditary [n = 6 (0.6%)], side-effect to antiarrhythmics [n = 6 (0.6%)], planned His-ablation [n = 5 (0.5%)], complication to alcohol septal ablation [n = 5 (0.5%)], and other known aetiologies [n = 11 (1.1%)]. The aetiology remained unknown in 517 (50.3%) cases. While the number of patients with unknown aetiology increased during the study period (P < 0.001), we observed no significant change in the number of patients with identified aetiology (P = 0.35). CONCLUSION: In a nationwide cohort, the aetiology of AVB was identified in only half the patients younger than 50 years referred for first-time pacemaker implantation. The number of patients with unknown aetiology increased during the study period. These findings indicate need for better insight into aetiologies of AVB and improved diagnostic work-up guidelines.

Primary Prevention of Sudden Cardiac Death With Implantable Cardioverter-Defibrillator Therapy in Patients With Arrhythmogenic Right Ventricular Cardiomyopathy.

Implantable cardioverter-defibrillator (ICD) therapy remains a corner stone of sudden cardiac death (SCD) prevention in patients with arrhythmogenic right ventricular cardiomyopathy (ARVC). We aimed to assess predictors of appropriate ICD therapies in the Scandinavian cohort of ARVC patients who received ICD for primary prevention of SCD. Study group comprised of 79 definite ARVC patients by 2010 Task Force criteria (60% male, age at ICD implant 39 ± 14 years) who were enrolled in the Nordic ARVC Registry and received an ICD for primary SCD prevention. The primary end point of appropriate ICD shock or death from any cause was assessed and compared with 137 definite ARVC patients who received ICD for secondary SCD prevention (74% male, age at ICD implant 42 ± 15 years). In the study group, 38% were ≤35 years of age at baseline, 25% had nonsustained ventricular tachycardia, and 29% had syncope at baseline. Major repolarization abnormality (hazard ratio = 4.00, 95% confidence interval 1.30 to 12.30, p = 0.015) and age ≤35 years (hazard ratio = 4.21, 95% confidence interval 1.49 to 11.85, p = 0.001) independently predicted the primary end point. The outcome did not differ between the primary prevention patients with either of these risk factors and the secondary prevention cohort (2% to 4% annual event rate) whereas patients without risk factors did not have any appropriate ICD shocks during follow-up. In conclusion, young age at ARVC diagnosis and major repolarization abnormality independently predict ICD shocks or death in the primary prevention ICD recipients and associated with the event rate similar to the one observed in the secondary prevention cohort. Our data indicate the benefit of ICD for primary prevention in patients with any of these risk factors.

Outcome of clinical management in relatives of sudden cardiac death victims.

BACKGROUND: International guidelines recommend clinical assessment of the surviving first-degree relatives of sudden cardiac death (SCD) victims to identify a probable cause of death and protect surviving relatives. Only few studies have reported the outcome of clinical management and follow-up of relatives to SCD victims. METHODS: We performed a retrospective cohort study of the clinical and genetic assessment of surviving relatives of SCD victims referred to the Clinic of Inherited Cardiac Diseases at Aarhus University Hospital, Denmark, between 1995 and 2016. We studied clinical and autopsy findings on all cases of SCD among children and adults. Relatives were followed for adverse cardiovascular events including cardiac hospitalization, new-onset heart failure, coronary heart disease, malignant syncope or documented malignant ventricular arrhythmias, and death. RESULTS: We included 292 relatives of 56 SCD victims. During a median (interquartile range) follow-up of 3.3 (1.6-4.7) years twelve relatives experienced an adverse cardiovascular event of which only five were related to the inherited cardiac disease in the family. One developed dilated cardiomyopathy and one tachycardia induced heart failure, five suffered from ventricular tachycardia or a malignant syncope and received a secondary prophylactic Implantable Cardioverter Defibrillator, three had a coronary heart disease event and two died from old age. CONCLUSION: Relatives of SCD victims have a low rate of adverse cardiac events when guideline-based assessment and care is applied.

Heart transplantation in arrhythmogenic right ventricular cardiomyopathy - Experience from the Nordic ARVC Registry.

OBJECTIVE: There is a paucity of data on heart transplantation (HTx) in patients with arrhythmogenic right ventricular cardiomyopathy (ARVC), and specific recommendations on indications for listing ARVC patients for HTx are lacking. In order to delineate features pertinent to HTx assessment, we explored the pre-HTx characteristics and clinical history in a cohort of ARVC patients who received heart transplants. METHODS: Data from 31 ARVC/HTx patients enrolled in the Nordic ARVC Registry, transplanted between 1988 and 2014 at a median age of 46years (14-65), were compared with data from 152 non-transplanted probands with Definite ARVC according to 2010 Task Force Criteria from the same registry. RESULTS: The HTx patients were younger at presentation, median 31 vs. 38years (p=0.001). There was no difference in arrhythmia-related events. The indication for HTx was heart failure in 28 patients (90%) and ventricular arrhythmias in 3 patients (10%). During median follow-up of 4.9years (0.04-28), there was one early death and two late deaths. Survival was 91% at 5years after HTx. Age at first symptoms under 35years independently predicted HTx in our cohort (OR=7.59, 95% CI 2.69-21.39, p<0.001). CONCLUSION: HTx in patients with ARVC is performed predominantly due to heart failure. This suggests that current 2016 International Society for Heart and Lung Transplantation heart transplant listing recommendations for other cardiomyopathies could be applicable in many cases when taking into account the haemodynamic consequences of right ventricular failure in conjunction with ventricular arrhythmia.

Truncating plakophilin-2 mutations in arrhythmogenic cardiomyopathy are associated with protein haploinsufficiency in both myocardium and epidermis.

BACKGROUND: Arrhythmogenic cardiomyopathy (AC) is a hereditary cardiac condition associated with ventricular arrhythmias, heart failure, and sudden death. The disease is most often caused by mutations in the desmosomal gene for plakophilin-2 (PKP2), which is expressed in both myocardial and epidermal tissue. This study aimed to investigate protein expression in myocardial tissue of patients with AC carrying PKP2 mutations and elucidate whether keratinocytes of the same individuals exhibited a similar pattern of protein expression. METHODS AND RESULTS: Direct sequencing of 5 AC genes in 71 unrelated patients with AC identified 10 different PKP2 mutations in 12 index patients. One patient, heterozygous for a PKP2 nonsense mutation, developed severe heart failure and underwent cardiac transplantation. Western blotting and immunohistochemistry of the explanted heart showed a significant decrease in PKP2 protein expression without detectable amounts of truncated PKP2 protein. Cultured keratinocytes of the patient showed a similar reduction in PKP2 protein expression. Nine additional PKP2 mutations were investigated in both cultured keratinocytes and endomyocardial biopsies from affected individuals. It was evident that PKP2 mutations introducing a premature termination codon in the reading frame were associated with PKP2 transcript and protein levels reduced to ≈50%, whereas a missense variant did not seem to affect the amount of PKP2 protein. CONCLUSIONS: The results of this study showed that truncating PKP2 mutations in AC are associated with low expression of the mutant allele and that the myocardial protein expression of PKP2 is mirrored in keratinocytes. These findings indicate that PKP2 haploinsufficiency contributes to pathogenesis in AC.

Mutations in Danish patients with long QT syndrome and the identification of a large founder family with p.F29L in KCNH2.

BACKGROUND: Long QT syndrome (LQTS) is a cardiac ion channelopathy which presents clinically with palpitations, syncope or sudden death. More than 700 LQTS-causing mutations have been identified in 13 genes, all of which encode proteins involved in the execution of the cardiac action potential. The most frequently affected genes, covering > 90% of cases, are KCNQ1, KCNH2 and SCN5A. METHODS: We describe 64 different mutations in 70 unrelated Danish families using a routine five-gene screen, comprising KCNQ1, KCNH2 and SCN5A as well as KCNE1 and KCNE2. RESULTS: Twenty-two mutations were found in KCNQ1, 28 in KCNH2, 9 in SCN5A, 3 in KCNE1 and 2 in KCNE2. Twenty-six of these have only been described in the Danish population and 18 are novel. One double heterozygote (1.4% of families) was found. A founder mutation, p.F29L in KCNH2, was identified in 5 "unrelated" families. Disease association, in 31.2% of cases, was based on the type of mutation identified (nonsense, insertion/deletion, frameshift or splice-site). Functional data was available for 22.7% of the missense mutations. None of the mutations were found in 364 Danish alleles and only three, all functionally characterised, were recorded in the Exome Variation Server, albeit at a frequency of < 1:1000. CONCLUSION: The genetic etiology of LQTS in Denmark is similar to that found in other populations. A large founder family with p.F29L in KCNH2 was identified. In 48.4% of the mutations disease causation was based on mutation type or functional analysis.

CT-guided needle lung biopsy is possible during apneic oxygenation: a case series.

BACKGROUND: It can be difficult to perform CT guided biopsy of small pulmonary nodules especially if the position is behind a costa or close to the diaphragm and respiratory movements may hamper the procedure. During apneic oxygenation with a pulmonary standstill these movements can be hindered. METHODS: Six patients with decreased lung function and suspicious lung nodules are presented. Under general anesthesia including a muscle relaxant and a cuffed tube in the trachea CT guided biopsy was prepared. Just before the biopsy the ventilation mode was switched to a continuous positive airway pressure of 5-10 cm H2O, maintaining 100% oxygen delivery without ventilation. If the position of the lung nodule was inconvenient for biopsy the pressure was increased to up to 17 cm H2O to expand the lungs to a better biopsy position. After retrieving the biopsy controlled ventilation was re-established and a finishing control CT-scan was performed. Blood gas analyses were performed with few minutes interval. RESULTS: All biopsies were diagnostic. All patients survived the procedure with no major complications, but 3 patients developed pneumothorax. The length of apneic oxygenation was median 10 minutes (8-10 minutes). No major changes in vital parameters were observed, and in all patients the peripheral oxygen saturation was 100% throughout the procedure. The arterial oxygen tension rose to very high values and the lowest pH was 7.18. CONCLUSIONS: It is possible to perform lung biopsies in selected patients with decreased lung function during apneic oxygenation in at least 10 minutes in a safe way.

Long QT interval in Turner syndrome--a high prevalence of LQTS gene mutations.

OBJECTIVES: QT-interval prolongation of unknown aetiology is common in Turner syndrome. This study set out to explore the presence of known long QT mutations in Turner syndrome and to examine the corrected QT-interval (QTc) over time and relate the findings to the Turner syndrome phenotype. METHODS: Adult women with Turner syndrome (n = 88) were examined thrice and 68 age-matched healthy controls were examined once. QTc was measured by one blinded reader (intra-reader variability: 0.7%), and adjusted for influence of heart rate by Bazett's (bQTc) and Hodges's formula (hQTc). The prevalence of mutations in genes related to Long QT syndrome was determined in women with Turner syndrome and a QTc >432.0 milliseconds (ms). Echocardiographic assessment of aortic valve morphology, 24-hour blood pressures and blood samples were done. RESULTS: The mean hQTc in women with Turner syndrome (414.0 ± 25.5 ms) compared to controls (390.4 ± 17.8 ms) was prolonged (p<0.001) and did not change over time (416.9 ± 22.6 vs. 415.6 ± 25.5 ms; p =0.4). 45,X karyotype was associated with increased hQTc prolongation compared to other Turner syndrome karyotypes (418.2 ± 24.8 vs. 407.6 ± 25.5 ms; p = 0.055). In women with Turner syndrome and a bQTc >432 ms, 7 had mutations in major Long QT syndrome genes (SCN5A and KCNH2) and one in a minor Long QT syndrome gene (KCNE2). CONCLUSION: There is a high prevalence of mutations in the major LQTS genes in women with TS and prolonged QTc. It remains to be settled, whether these findings are related to the unexplained excess mortality in Turner women. CLINICAL TRIAL REGISTRATION: NCT00624949. https://register.clinicaltrials.gov/prs/app/action/SelectProtocol/sid/S0001FLI/selectaction/View/ts/3/uid/U000099E.

Mutated desmoglein-2 proteins are incorporated into desmosomes and exhibit dominant-negative effects in arrhythmogenic right ventricular cardiomyopathy.

Arrhythmogenic right ventricular cardiomyopathy (ARVC) is a hereditary cardiac condition associated with ventricular arrhythmias, heart failure, and sudden death. The most frequent ARVC genes encode desmosomal proteins of which mutations in desmoglein-2 (DSG2), account for 10%-20% of cases. This study aimed to investigate how DSG2 mutations contribute to the pathogenesis of ARVC. Initial mutation analysis of DSG2 in 71 probands identified the first family reported with recessively inherited ARVC due to a missense mutation. In addition, three recognized DSG2 mutations were identified in 12 families. These results and further mutation analyses of four additional desmosomal genes indicated that ARVC caused by DSG2 mutations is often transmitted by recessive or digenic inheritance. Because desmosomal proteins are also expressed in skin tissue, keratinocytes served as a cell model to investigate DSG2 protein expression by Western blotting, 2D-PAGE, and liquid chromatography-mass spectrometry. The results showed that heterozygous mutation carriers expressed both mutated and wild-type DSG2 proteins. These findings were consistent with the results obtained by immunohistochemistry of endomyocardial biopsies and epidermal tissue of mutation carriers, which indicated a normal cellular distribution of DSG2. The results suggested a dominant-negative effect of the mutated DSG2 proteins because they were incorporated into the desmosomes.

Amiodarone significantly decreases atrial fibrillation in patients undergoing surgery for lung cancer.

BACKGROUND: Postoperative atrial fibrillation occurs in 5% to 65% of patients undergoing thoracic surgery. Although postoperative atrial fibrillation often is regarded as a temporary, benign, operation-related problem, it is associated with a twofold to threefold increase in risk of adverse events, including transient or permanent stroke, acute myocardial infarction, and death. METHODS: A total of 254 consecutively eligible enrolled patients undergoing surgery for lung cancer were included in this randomized, controlled, double-blinded trial. Patients received 300 mg of amiodarone or placebo intravenously over 20 minutes immediately after surgery and an oral dose of 600 mg of amiodarone or placebo twice daily during the first 5 postoperative days. RESULTS: The patients in the amiodarone prophylaxis group had a reduction in the risk of atrial fibrillation of 23% (12 to 31); number needed to treat was 4.4 (3.1 to 7.8). A total of 38 in the control group and 11 in the amiodarone group experienced atrial fibrillation (p<0.001). Adverse effects were observed in 10 patients equally distributed in both trial arms. CONCLUSIONS: Postoperative prophylaxis with a high dose of oral amiodarone after an intravenous bolus infusion is a safe, practical, feasible, and effective regimen for patients with lung cancer undergoing surgery. It significantly reduced the incidence of postoperative atrial fibrillation.