Incidence of Atrial Fibrillation as the Initial Manifestation of Cardiac Sarcoidosis: Insights From a Catheter Ablation Registry.

Background: Cardiac sarcoidosis (CS) is a rare form of arrhythmogenic cardiomyopathy; a delayed diagnosis can lead to significant consequences. Patients with clinically manifest CS often have minimal extracardiac involvement and thus frequently present initially to cardiology. Indeed, certain specific arrhythmic scenarios should trigger investigations for undiagnosed CS. Atrial fibrillation (AF) has been described as one of the presenting features of CS; however, the incidence of this presentation is not known. Methods: At our institution, cardiac computerized tomography is routinely performed prior to catheter ablation for AF. Noncardiac incidental findings are described by radiologists and are followed-up by interval investigations. We systematically reviewed noncardiac reports from 1574 consecutive patients in our prospective AF ablation registry. Specifically, we used text-scraping techniques to search on the following keywords: "adenopathy" and "sarcoidosis." Detailed chart review of identified cases was then performed to evaluate results of interval investigations and assess long-term outcomes. Results: Twenty of 1574 patients (1.3%) had noncardiac reports containing "adenopathy" and/or "sarcoidosis." After interval imaging and a follow-up period averaging 60 ± 35 months, only 2 patients of 1574 (0.13%) were diagnosed with CS. Four of 20 (20%) had a previous history of extracardiac sarcoidosis, and another 1 of 20 (5%) was subsequently diagnosed with extracardiac sarcoidosis. However, none of these 5 patients had evidence of cardiac involvement. Conclusions: CS is a rare finding among patients undergoing a first-time AF ablation. Our findings suggest that AF is an uncommon initial presentation of CS. Thus, investigations for CS in patients with AF are not warranted routinely, unless additional suggestive clinical features are present.

Contexte: La sarcoïdose cardiaque (SC) est une forme rare de cardiomyopathie arythmogène; un retard dans le diagnostic peut entraîner d'importantes conséquences. Les patients qui présentent une SC cliniquement manifeste ont souvent une atteinte extracardiaque minime, et consultent donc souvent d'abord en cardiologie. En effet, certains scénarios arythmiques précis devraient déclencher la recherche de signes d'une SC non diagnostiquée. La fibrillation auriculaire (FA) a été décrite comme un signe indicateur de SC; on ne connaît toutefois pas l'incidence de ce signe. Méthodologie: Dans notre établissement, la tomodensitométrie cardiaque est souvent réalisée avant une ablation par cathéter de la FA. Les découvertes non cardiaques fortuites sont décrites par les radiologues, puis font l'objet d'un suivi par des examens d'imagerie réalisés à intervalles déterminés. Nous avons systématiquement évalué les éléments non cardiaques signalés chez 1 574 patients consécutifs dans notre registre prospectif sur l'ablation de la FA. Nous avons utilisé des techniques de dépouillement du texte pour trouver les mots-clés suivants : « adenopathy ¼ (adénopathie) et « sarcoidosis ¼ (sarcoïdose). Un examen du dossier médical complet des cas retenus a été réalisé pour évaluer les résultats des examens de suivi et évaluer les résultats à long terme. Résultats: Parmi les 1 574 patients, 20 (1,3 %) présentaient des notes non cardiaques contenant les termes « adenopahy ¼ (adénopathie) ou « sarcoidosis ¼ (sarcoïdose). Après l'examen d'imagerie et une période de suivi d'une durée moyenne de 60 ±35 mois, seuls deux patients (0,13 %) ont reçu un diagnostic de SC. Quatre des 20 patients visés (20 %) présentaient des antécédents de sarcoïdose extracardiaque, et un patient sur 20 (5 %) a reçu un diagnostic de sarcoïdose extracardiaque à la suite de l'intervention. Toutefois, aucun de ces cinq patients ne montrait de signes d'atteinte cardiaque. Conclusions: La SC est une occurrence rare chez les patients qui subissent une première ablation de la FA. Nos constats indiquent que la FA est une présentation initiale peu commune de la SC. Aussi, la recherche de la SC chez les patients atteints de FA n'est pas justifiée dans une procédure de routine, à moins que d'autres caractéristiques cliniques pointant vers cette affection ne soient présentes.

Arrhythmic Events and Mortality in Patients With Cardiogenic Shock on Inotropic Support: Results of the DOREMI Randomized Trial.

BACKGROUND: Inotropic support is widely used in the management of cardiogenic shock (CS). Existing data on the incidence and significance of arrhythmic events in patients with CS on inotropic support is at high risk of bias. METHODS: The Dobutamine Compared to Milrinone (DOREMI) trial randomized patients to receive dobutamine or milrinone in a double-blind fashion. Patients with and without arrhythmic events (defined as arrhythmias requiring intervention or sustained ventricular arrhythmias) were compared to identify factors associated with their occurrence, and to examine their association with in-hospital mortality and secondary outcomes. RESULTS: Ninety-two patients (47.9%) had arrhythmic events, occurring equally with dobutamine and milrinone (P = 0.563). The need for vasopressor support at initiation of the inotrope and a history of atrial fibrillation were positively associated with arrhythmic events, whereas predominant right ventricular dysfunction, previous myocardial infarction, and increasing left ventricular ejection fraction were negatively associated with them. Supraventricular arrhythmic events were not associated with mortality (relative risk [RR], 0.97; 95% confidence interval [CI], 0.68-1.40; P = 0.879) but were positively associated with resuscitated cardiac arrests and hospital length of stay. Ventricular arrhythmic events were positively associated with mortality (RR, 1.66; 95% CI, 1.13-2.43; P = 0.026) and resuscitated cardiac arrests. Arrhythmic events were most often treated with amiodarone (97%) and electrical cardioversion (27%), which were not associated with mortality. CONCLUSIONS: Clinically relevant arrhythmic events occur in approximately one-half of patients with CS treated with dobutamine or milrinone and are associated with adverse clinical outcomes. Five factors may help to identify patients most at risk of arrhythmic events.

Should they stay, or should they go: Do we need to remove the old cardiac implantable electronic device if a new system is required on the contralateral side?

Background: Ipsilateral approach in patients requiring cardiac implantable electronic device (CIED) revision or upgrade may not be feasible, primarily due to vascular occlusion. If a new CIED is implanted on the contralateral side, a common practice is to explant the old CIED to avoid device interaction. Objective: The purpose of this study was to assess a conservative approach of abandoning the old CIED after implanting a new contralateral device. Methods: We used an artificial intelligence algorithm to analyze postimplant chest radiographs to identify those with multiple CIEDs. Outcomes of interest included device interaction, abandoned CIED elective replacement indicator (ERI) behavior, subsequent programming changes, and explant of abandoned CIED. Theoretical risk of infection with removal of abandoned CIED was estimated using a validated scoring system. Results: Among 12,045 patients, we identified 40 patients with multiple CIEDs. Occluded veins were the most common indication for contralateral implantation (n = 27 [67.5%]). Fifteen abandoned CIEDs reached ERI, with 4 reverting to VVI 65. One patient underwent explant due to device interaction, and 2 required device reprogramming. Of 32 patients with an implantable cardioverter-defibrillator, 8 (25%) had treated ventricular arrhythmia. There were no failed or inappropriate therapies due to interaction. Eighteen patients (45%) had hypothetical >1% annual risk of hospitalization for device infection if the abandoned CIED had been explanted. Conclusion: In patients requiring new CIED implant on the contralateral side, abandoning the old device is feasible. This approach may reduce the risk of infection and concerns regarding abandoned leads and magnetic resonance imaging scans. Knowledge of ERI behavior is essential to avoid device interactions.

Outcomes of a comprehensive strategy during repeat atrial fibrillation ablation.

BACKGROUND/PURPOSE: Atrial fibrillation (AF) recurs post-ablation in 30-40% of patients. The approach to a repeat ablation, beyond isolation of reconnected pulmonary veins (PVs), is not well established. We sought to prospectively assess outcomes and predictors of recurrence among consecutive patients who underwent repeat AF ablation with a standardized approach. METHODS: This was a single-center prospective study of consecutive patients who underwent repeat AF ablation. Our protocol consisted of six steps: PV re-isolation, ablation of left atrial low-voltage areas (LVAs), ablation of isoproterenol-induced non-PV triggers, electrophysiology study (EPS) and ablation of induced AVNRT/AVRT, ablation of induced clinical atrial flutters, and lastly empiric ablation as per operator discretion if no other ablation was performed. RESULTS: Among 725 AF ablations performed during the study period, 74 were repeat ablations. Of those undergoing repeat ablation, 53 (72%) had PV reconnection, 30 (41%) had LVAs, seven (10%) had non-PV triggers, five (7%) had AVNRT, and 15 (20%) had typical atrial flutter. Following repeat ablation, arrhythmia-free survival was 65% at 1 year. The absence of PV reconnection was the only factor independently associated with recurrence after repeat ablation (recurrence rate 71%, adjusted OR 7.91, 95% CI 2.31-27.16, p = 0.001). CONCLUSIONS: A comprehensive approach to repeat AF ablation including PV re-isolation, LVA ablation, non-PV trigger ablation, EPS, and flutter ablation was associated with a 65% 1-year arrhythmia-free survival. The absence of PV reconnection was the only independent predictor of arrhythmia recurrence. Further research is needed to identify therapies beyond PV isolation for patients undergoing repeat ablation.

Significant Valvular Dysfunction and Outcomes in Cardiogenic Shock: Insights From the Randomized DOREMI Trial.

BACKGROUND: Patients with cardiogenic shock (CS) suffer high rates of in-hospital mortality, with little evidence guiding management. The impact of valvular heart disease in patients with CS remains unclear. We therefore conducted a post hoc analysis of the randomized Dobutamine Compared to Milrinone (DOREMI) trial to determine the impact of valvular disease on outcomes in patients with CS. METHODS: We defined significant valvular disease as moderate to severe or greater valvular stenosis or regurgitation and divided participants into a group of those with significant valvular disease and those without. Our primary outcome was all-cause in-hospital mortality. Secondary endpoints included resuscitated cardiac arrest; cardiac transplantation or mechanical circulatory support; nonfatal myocardial infarction; stroke; initiation of renal replacement therapy; as well as changes in renal function, perfusion, and hemodynamics over time. RESULTS: One hundred eighty-nine (98.4%) participants from the DOREMI trial were included in our analysis, and 74 (39.2%) had significant valvular dysfunction. Thirty-six (48.7%) patients with valvular disease died in hospital, compared with 37 (32.2%) in the comparator group (relative risk, 1.5; 95% confidence interval 1.06-2.15; P = 0.02). Patients with aortic stenosis (2.42, 1.56-3.75; P < 0.01) and patients with mitral regurgitation (1.63, 1.1-2.43; P = 0.02) also had increased incidence of in-hospital mortality. There was no significant difference in any secondary outcomes among groups, apart from variances in mean arterial pressure observed in patients with valvular disease (P < 0.01). CONCLUSIONS: Significant valvular dysfunction is associated with increased in-hospital mortality in patients with CS. Randomized clinical trial data are needed to further elucidate the role of transcatheter valvular interventions as a therapeutic target in this population.

Investigating the treatment phenotypes of cardiac sarcoidosis: A prospective cohort study.

Introduction: Data indicates there are 4 main pulmonary sarcoidosis duration/treatment phenotypes: asymptomatic, acute (disease duration <1-2 years), chronic and advanced. There are no data about disease duration/treatment phenotypes of cardiac sarcoidosis patients. Our study had 2 main aims (i) to assess the response to corticosteroids and (ii) to assess the incidence of relapse after a one-year course of corticosteroids (thereby classifying patients as acute or chronic treatment phenotype). Methods: Consecutive, treatment naive patients with CS were prospectively recruited and treated with 0.5 mg/kg prednisone, to a maximum dose of 40 mg/day. Patients had a follow-up PET after 3-6 months of therapy (PET 2). In the responders (PET definition of response) the prednisone was then weaned and stopped after 12 months. Three months after stopping, the PET was repeated to look for disease relapse (PET 3). Results: Twenty-one consecutive patients were included, and all patients showed a reduction in cardiac FDG uptake after 3-6 months and 19/21 (90.5 %) met the PET definition of response. Of these, 12/19 (63.1 %) relapsed after prednisone was stopped. There were no serious adverse effects during the trial of therapy cessation and there were no later relapses in the 7 non-relapsers during over 4 years of subsequent follow-up. Conclusion: The initial response rate to prednisone was high with all patients showing a reduction in FDG uptake and 19/21 meeting a PET definition of >25 % response. Secondly, a trial of therapy discontinuation was able to classify 7/19 patients as acute treatment phenotype and 12/19 as chronic.

The role of brain natriuretic peptide in atrial fibrillation: a substudy of the Substrate Modification with Aggressive Blood Pressure Control for Atrial Fibrillation (SMAC-AF) trial.

BACKGROUND: Catheter ablation is an established therapy for atrial fibrillation but is limited by recurrence; efforts have been made to identify biomarkers that predict recurrence. We investigated the effect of baseline NT-proBNP on AF recurrence following catheter ablation in patients randomized to aggressive (< 120/80 mmHg) or standard blood pressure management (< 140/90 mmHg) in the Substrate Modification with Aggressive Blood Pressure Control trial (SMAC-AF). METHODS: The SMAC-AF study included 173 patients resistant or intolerant to at least one class I or III antiarrhythmic drug. We studied the effect of baseline NT-proBNP on the primary outcome of AF recurrence > 3 months post-ablation. RESULTS: Of the 173 patients, 88 were randomized to the aggressive cohort, and 85 into the standard group. The primary outcome occurred in 61.4% of those in the aggressive arm, versus 61.2% in the standard arm. In the aggressive group, logNT-proBNP predicted recurrence (HR 1.28, p = 0.04, adjusted HR 1.43, p = 0.03), while in the standard cohort, it did not (HR 0.94, p = 0.62, adjusted HR 0.83, p = 0.22). NT-proBNP ≥ 280 pg/mL also predicted occurrence in the aggressive (HR 1.98, p = 0.02) but not the standard cohort (HR 1.00, p = 1.00). CONCLUSION: We conclude that pre-ablation NT-proBNP may be useful in predicting recurrence in hypertensive patients and identifying patients who benefit from aggressive blood control and upstream therapies. TRIAL REGISTRATION: NCT00438113, registered February 21, 2007.

Milrinone as Compared with Dobutamine in the Treatment of Cardiogenic Shock.

BACKGROUND: Cardiogenic shock is associated with substantial morbidity and mortality. Although inotropic support is a mainstay of medical therapy for cardiogenic shock, little evidence exists to guide the selection of inotropic agents in clinical practice. METHODS: We randomly assigned patients with cardiogenic shock to receive milrinone or dobutamine in a double-blind fashion. The primary outcome was a composite of in-hospital death from any cause, resuscitated cardiac arrest, receipt of a cardiac transplant or mechanical circulatory support, nonfatal myocardial infarction, transient ischemic attack or stroke diagnosed by a neurologist, or initiation of renal replacement therapy. Secondary outcomes included the individual components of the primary composite outcome. RESULTS: A total of 192 participants (96 in each group) were enrolled. The treatment groups did not differ significantly with respect to the primary outcome; a primary outcome event occurred in 47 participants (49%) in the milrinone group and in 52 participants (54%) in the dobutamine group (relative risk, 0.90; 95% confidence interval [CI], 0.69 to 1.19; P = 0.47). There were also no significant differences between the groups with respect to secondary outcomes, including in-hospital death (37% and 43% of the participants, respectively; relative risk, 0.85; 95% CI, 0.60 to 1.21), resuscitated cardiac arrest (7% and 9%; hazard ratio, 0.78; 95% CI, 0.29 to 2.07), receipt of mechanical circulatory support (12% and 15%; hazard ratio, 0.78; 95% CI, 0.36 to 1.71), or initiation of renal replacement therapy (22% and 17%; hazard ratio, 1.39; 95% CI, 0.73 to 2.67). CONCLUSIONS: In patients with cardiogenic shock, no significant difference between milrinone and dobutamine was found with respect to the primary composite outcome or important secondary outcomes. (Funded by the Innovation Fund of the Alternative Funding Plan for the Academic Health Sciences Centres of Ontario; ClinicalTrials.gov number, NCT03207165.).

A virtual platform to deliver ambulatory care for patients with atrial fibrillation.

Background: There are little data on the use of virtual care for patients with arrhythmia. We evaluated a virtual clinic platform, in conjunction with specialist care, for patients with symptomatic atrial fibrillation (AF). Methods: This was a prospective, observational cohort study evaluating an online educational and treatment platform, with a randomized sub-study examining the use of an ambulatory single-lead electrocardiogram heart monitor (AHM). Follow-up was 6 months. The main outcome was patients' platform use; success was defined as 90% of patients using the platform at least once, and 75% using it at least twice. The primary outcome in the AHM sub-study was Atrial Fibrillation Symptom Severity (AFSS) score. Other outcomes included patient satisfaction questionnaires, quality of life, emergency department visits, and hospitalizations for AF. Results: We enrolled 94 patients between July 2018 and May 2019; 83% of patients logged in at least once and 54.3% more than once. Patients who were older, were male, or had new-onset AF were more likely to log in to the platform. Satisfaction scores were high; 70%-94% of patients responded favorably. Quality-of-life scores improved at 3 and 6 months. In the AHM sub-study (n = 71), those who received an AHM had lower AFSS scores (least square mean difference -2.52, 95% CI -4.48 to -0.25, P = .03). There was no difference in emergency department visits or hospitalizations. Conclusion: The online platform did not reach our feasibility target but was well received. Allocation of an AHM was associated with improved quality of life. Virtual AF care shows promise and should be evaluated in further research.

Atrial Arrhythmias in Clinically Manifest Cardiac Sarcoidosis: Incidence, Burden, Predictors, and Outcomes.

Background Recent data have suggested a substantial incidence of atrial arrhythmias (AAs) in cardiac sarcoidosis (CS). Our study aims were to first assess how often AAs are the presenting feature of previously undiagnosed CS. Second, we used prospective follow-up data from implanted devices to investigate AA incidence, burden, predictors, and response to immunosuppression. Methods and Results This project is a substudy of the CHASM-CS (Cardiac Sarcoidosis Multicenter Prospective Cohort Study; NCT01477359). Inclusion criteria were presentation with clinically manifest cardiac sarcoidosis, treatment-naive status, and implanted with a device that reported accurate AA burden. Data were collected at each device interrogation visit for all patients and all potential episodes of AA were adjudicated. For each intervisit period, the total AA burden was obtained. A total of 33 patients met the inclusion criteria (aged 56.1±7.7 years, 45.5% women). Only 1 patient had important AAs as a part of the initial CS presentation. During a median follow-up of 49.1 months, 11 of 33 patients (33.3%) had device-detected AAs, and only 2 (6.1%) had a clinically significant AA burden. Both patients had reduced burden after CS was successfully treated and there was no residual fluorodeoxyglucose uptake on positron emission tomography scan. Conclusions First, we found that AAs are a rare presenting feature of clinically manifest cardiac sarcoidosis. Second, AAs occurred in a minority of patients at follow-up; the burden was very low in most patients. Only 2 patients had clinically significant AA burden, and both had a reduction after CS was treated. Registration URL: https://www.clini​caltr​ials.gov; unique identifier NCT01477359.

Benefit of Implantable Cardioverter-Defibrillator Generator Replacement in a Primary Prevention Population-Based Cohort.

OBJECTIVES: This study investigated the benefit of an implantable cardioverter-defibrillator (ICD) generator replacement in patients who did not have an ongoing theoretical indication for ICD therapy at time of replacement. BACKGROUND: Primary prevention ICD therapy is known to reduce mortality in patients with cardiomyopathy and reduced left ventricular systolic function. The data describing outcomes after generator replacement are limited. METHODS: This was a retrospective cohort study following patients implanted with primary prevention ICD therapy from 2002 until 2015 who subsequently received a generator replacement. Patients with an ongoing theoretical indication for ICD therapy were defined as either left ventricular ejection fraction ≤35% or having had prior appropriate ICD therapy. Outcomes were mortality, appropriate ICD therapy and shock, inappropriate shock, and device and lead complications. RESULTS: A total of 614 patients were identified; 173 (28.2%) underwent a generator replacement and were followed for a mean of 2.9 years after replacement; 144 (83.2%) had an ongoing theoretical indication. Patients with no ongoing theoretical indication (n = 29, 16.7%) had lower mortality (hazard ratio [HR]: 0.39, 95% confidence interval [CI]: 0.15-1.00; p = 0.0495), appropriate shock rate (HR: 0.29, 95% CI: 0.09 to 0.96; p = 0.04), and appropriate ICD therapy rate (HR: 0.30, 95% CI: 0.12 to 0.77; p = 0.012) when compared with patients with ongoing theoretical indication. In the entire cohort, there were low rates of inappropriate shock (4.0%), device complication (5.1%), and lead complication (2.3%). CONCLUSIONS: In patients with primary prevention ICD therapy who underwent generator replacement, improved left ventricular ejection fraction and lack of prior appropriate ICD therapy at time of replacement were associated with a lower risk of mortality and incident ventricular arrhythmia.

Low density lipoprotein binds to proprotein convertase subtilisin/kexin type-9 (PCSK9) in human plasma and inhibits PCSK9-mediated low density lipoprotein receptor degradation.

Proprotein convertase subtilisin/kexin type-9 (PCSK9) is a secreted protein that binds to the epidermal growth factor-like-A domain of the low density lipoprotein receptor (LDLR) and mediates LDLR degradation in liver. Gain-of-function mutations in PCSK9 are associated with autosomal dominant hypercholesterolemia in humans. Size-exclusion chromatography of human plasma has shown PCSK9 to be partly associated with undefined high molecular weight complexes within the LDL size range. We used density gradient centrifugation to isolate LDL in plasma pooled from 5 normolipidemic subjects and report that >40% of total PCSK9 was associated with LDL. Binding of fluorophore-labeled recombinant PCSK9 to isolated LDL in vitro was saturable with a K(D) ∼ 325 nM. This interaction was competed >95% by excess unlabeled PCSK9, and competition binding curves were consistent with a one-site binding model. An N-terminal region of the PCSK9 prodomain (amino acids 31-52) was required for binding to LDL in vitro. LDL dose-dependently inhibited binding and degradation of cell surface LDLRs by exogenous PCSK9 in HuH7 cells. LDL also inhibited PCSK9 binding to mutant LDLRs defective at binding LDL. These data suggest that association of PCSK9 with LDL particles in plasma lowers the ability of PCSK9 to bind to cell surface LDLRs, thereby blunting PCSK9-mediated LDLR degradation.

Evaluation of dose-related effects of aspirin on platelet function: results from the Aspirin-Induced Platelet Effect (ASPECT) study.

BACKGROUND: The antiplatelet effect of aspirin is attributed to platelet cyclooxygenase-1 inhibition. Controversy exists on the prevalence of platelet resistance to aspirin in patients with coronary artery disease and effects of aspirin dose on inhibition. Our primary aim was to determine the degree of platelet aspirin responsiveness in patients, as measured by commonly used methods, and to study the relation of aspirin dose to platelet inhibition. METHODS AND RESULTS: We prospectively studied the effect of aspirin dosing on platelet function in 125 stable outpatients with coronary artery disease randomized in a double-blind, double-crossover investigation (81, 162, and 325 mg/d for 4 weeks each over a 12-week period). At all doses of aspirin, platelet function was low as indicated by arachidonic acid (AA)-induced light transmittance aggregation, thrombelastography, and VerifyNow. At any 1 dose, resistance to aspirin was 0% to 6% in the overall group when AA was used as the agonist, whereas it was 1% to 27% by other methods [collagen and ADP-induced light transmittance aggregation, platelet function analyzer (PFA-100)]. Platelet response to aspirin as measured by collagen-induced light transmittance aggregation, ADP-induced light transmittance aggregation, PFA-100 (81 mg versus 162 mg, P < or = 0.05), and urinary 11-dehydrothromboxane B2 was dose-related (81 mg versus 325 mg, P = 0.003). No carryover effects were observed. CONCLUSIONS: The assessment of aspirin resistance is highly assay-dependent; aspirin is an effective blocker of AA-induced platelet function at all doses, whereas higher estimates of resistance were observed with methods that do not use AA as the stimulus. The observation of dose-dependent effects despite nearly complete inhibition of AA-induced aggregation suggests that aspirin may exert antiplatelet properties through non-cyclooxygenase-1 pathways and deserves further investigation.