The Canadian WATCHMAN Registry for Percutaneous Left Atrial Appendage Closure.

Background: Access to left atrial appendage closure (LAAC) in Canada is limited, due to funding restrictions. This work aimed to assess Canadian clinical practice on patient selection, postprocedural antithrombotic therapy, and safety and/or efficacy with WATCHMAN device implantation. Methods: Seven Canadian centres implanting the WATCHMAN device participated in this prospective multicentre, observational registry. All procedures were done under general anesthesia with transesophageal echocardiography guidance. Patients were prospectively followed for 2years. The long-term stroke rate was compared with the expected rate based on the CHA2DS2-VASc score. Results: A total of 272 patients who underwent LAAC with the WATCHMAN device between December 2013 and August 2019 (mean age: 75.4 years [standard deviation {SD}: 8.75]; male, 63.2%; CHA2DS2-VASc score: 4.35 [SD: 1.64]; HAS-BLED score: 3.55 [SD: 0.94]) were included. Most patients (90.4%) had prior history of bleeding (major, 80.5%; minor, 21.7%). The WATCHMAN device was successfully implanted in 269 patients (98.9%), with a few procedure-related complications, including 5 pericardial effusions requiring drainage (1.8%), and 1 death (0.4%; 22 days post-LAAC from respiratory failure). Post-LAAC antithrombotic therapy included dual antiplatelet therapy in 70.6%, single antiplatelet therapy in 18.4%, and oral anticoagulation in 13.6%. During the follow-up period (mean: 709.7 days [SD: 467.2]), an 81.4% reduction of the ischemic stroke rate occurred, based on the expected rate from the CHA2DS2-VASc score (6.0% expected vs 1.1% observed). Device-related thrombus was detected in 1.8%. Conclusions: The majority of Canadian patients who underwent LAAC had oral anticoagulation contraindication due to prior bleeding, and most were safely treated with antiplatelet therapy post-LAAC, with a low device-related thrombus incidence. Long-term follow-up demonstrated that LAAC achieved a significant reduction in ischemic stroke rate.

Contexte: Au Canada, l'accès à la fermeture de l'appendice auriculaire gauche (FAAG) est limité en raison de restrictions quant au financement de cette intervention. Le présent rapport visait à évaluer les pratiques cliniques canadiennes sur la sélection des patients, le traitement antithrombotique après l'intervention et l'innocuité ou l'efficacité par l'implantation d'un dispositif WATCHMAN. Méthodologie: Sept centres canadiens procédant à l'implantation du dispositif WATCHMAN ont participé à ce registre observationnel, prospectif et multicentrique. Toutes les interventions ont été réalisées sous anesthésie générale avec guidage par échocardiographie transœsophagienne. Les patients ont par la suite été suivis de manière prospective pendant deux ans. Le taux d'AVC à long terme a été comparé au taux attendu, selon le score CHA2DS2-VASc. Résultats: Ont été inclus à l'étude 272 patients ayant subi une FAAG avec implantation d'un dispositif WATCHMAN entre décembre 2013 et août 2019 (âge moyen : 75,4 ans [écart-type {É.-T.} : 8,75]; hommes : 63,2 %; score CHA2DS2-VASc : 4,35 [É.-T. : 1,64]; score HAS-BLED : 3,55 [É.-T. : 0,94]). La plupart des patients (90,4 %) avaient des antécédents de saignements (majeurs : 80,5 %; mineurs : 21,7 %). Le dispositif WATCHMAN a bien été implanté chez 269 patients (98,9 %), avec quelques complications associées à l'intervention, dont cinq effusions péricardiques nécessitant un drainage (1,8 %) et un décès (0,4 %; 22 jours après la FAAG, en raison d'une insuffisance respiratoire). Le traitement antithrombotique après la FAAG comprenait une bithérapie antiplaquettaire dans 70,6 % des cas, une monothérapie antiplaquettaire dans 18,4 % des cas et une anticoagulothérapie orale dans 13,6 % des cas. Pendant la période de suivi (durée moyenne : 709,7 jours [É.-T. : 467,2]), on a noté une réduction de 81,4 % du taux d'AVC ischémique observé par rapport au taux attendu selon le score CHA2DS2-VASc (taux attendu : 6,0 %; taux observé : 1,1 %). Un thrombus associé au dispositif a été détecté dans 1,8 % des cas. Conclusions: La majorité des patients canadiens qui ont subi une FAAG présentaient des contre-indications à l'anticoagulothérapie orale en raison de leurs antécédents de saignements, et la plupart ont été traités de manière sécuritaire par des thérapies antiplaquettaires après la chirurgie, avec un faible taux d'incidence de thrombus associé au dispositif. Le suivi à long terme a montré que la FAAG permet d'obtenir une réduction importante du taux d'AVC ischémique.

Leadless Pacemaker Implantation in a Patient With Hypoplasia of the Left Brachiocephalic Vein.

Venous anomalies are typically asymptomatic and may be discovered unexpectedly at the time of implantation of a cardiac implantable electronic device. We report a case of leadless pacemaker implantation in a patient with hypoplasia of the left brachiocephalic vein who had previously undergone multiple interventions for relapsing right-sided breast cancer. The prevalence and etiology of this anatomic variant remain unknown. However, awareness of its existence may prevent complications during left-sided interventions. such as placement of a central venous line or a cardiac implantable electronic device. Alternative diagnostics and implantation strategies are discussed.

Les anomalies veineuses sont généralement asymptomatiques et peuvent être découvertes de façon inattendue au moment de l'implantation d'un dispositif cardiaque électronique. Nous présentons un cas d'implantation d'un stimulateur cardiaque sans sonde chez une patiente atteinte d'hypoplasie de la veine brachiocéphalique gauche qui avait déjà subi de nombreuses interventions en raison de la rechute d'un cancer du sein du côté droit. On ignore la prévalence et l'étiologie de cette variante anatomique. Toutefois, la sensibilisation à son existence peut permettre de prévenir les complications durant les interventions du côté gauche telles que la pose d'un cathéter veineux central ou l'implantation d'un dispositif cardiaque électronique. Les autres diagnostics et stratégies d'implantation font l'objet de discussions.

Rate, Time Course, and Predictors of Implantable Cardioverter Defibrillator Infections: An Analysis From the SIMPLE Trial.

BACKGROUND: The number of implantable cardioverter defibrillator (ICD) infections is increasing due to an increased number of ICD implants, higher-risk patients, and more frequent replacement procedures, which carry a higher risk of infection. Reducing the morbidity, mortality, and cost of ICD-related infections requires an understanding of the current rate of this complication and its predictors. METHODS: The Shock Implant Evaluation Trial (SIMPLE) trial randomized 2500 ICD recipients to defibrillation testing or not. Over an average of 3.1 years, patients were seen every 6 months and examined for evidence of ICD infection, which was defined as requiring device removal and/or intravenous antibiotics. RESULTS: Within 24 months, 21 patients (0.8%) developed infection. Fourteen patients (67%) with infection presented within 30 days, 20 patients by 12 months, and only 1 patient beyond 12 months. Univariate analysis demonstrated that patients with primary electrical disorders (3 patients, P = 0.009) and those with a secondary prevention indication (13 patients, P = 0.0009) were more likely to develop infection. Among the 2.2% of patients who developed an ICD wound hematoma, 10.4% developed an infection. Among the 8.3% of patients requiring an ICD reintervention, 1.9% developed an infection. CONCLUSIONS: This cohort of ICD recipients at high-volume centres have a low risk of device-related infection. However; strategies to reduce wound hematoma and the need for ICD reintervention could further reduce the rate of infection.

CONTEXTE: L'incidence des cas d'infection du défibrillateur cardioverteur implantable (DCI) augmente en raison du nombre accru d'implantations, de l'emploi de ces dispositifs chez des patients exposés à un risque très élevé et de l'augmentation de la fréquence des interventions de remplacement, qui sont associées à un plus grand risque d'infections. Pour parvenir à réduire la morbidité, la mortalité et les coûts associés aux infections liées à un DCI, il faut connaître la fréquence de cette complication et les facteurs qui permettent de la prédire. MÉTHODOLOGIE: Lors de l'essai S hock Impl ant E valuation Trial (SIMPLE), 2 500 patients ayant reçu un DCI ont été répartis aléatoirement en deux groupes, l'un subissant des tests de défibrillation et l'autre, non. Sur une période de 3,1 ans en moyenne, les patients ont été vus en consultation tous les 6 mois et examinés à la recherche de signes d'infection du DCI, définie comme étant une infection exigeant le retrait du dispositif et/ou l'administration d'antibiotiques par voie intraveineuse. RÉSULTATS: Au total, 21 patients (0,8 %) ont présenté une infection dans les 24 mois suivant l'implantation. Quatorze patients (67 %) ont présenté une infection dans les 30 jours suivant l'intervention; à 12 mois, 20 patients avaient présenté une infection. Un seul patient a présenté une infection plus de 12 mois après l'intervention. Les résultats d'une analyse univariée ont démontré qu'une infection était plus probable chez les patients qui présentaient un trouble électrique primaire (3 patients, p = 0,009) et chez ceux qui avaient reçu un dispositif en prévention secondaire (13 patients, p = 0,0009). Parmi les patients qui présentaient un hématome après l'implantation du DCI (2,2 %), 10,4 % ont présenté une infection. Parmi les patients qui ont eu besoin d'une nouvelle intervention relative au DCI (8,3 %), 1,9 % ont présenté une infection. CONCLUSIONS: Les patients de cette cohorte ayant reçu un DCI dans des établissements à haut volume étaient exposés à un faible risque d'infection du défibrillateur. Des stratégies visant à réduire les hématomes et la nécessité d'une nouvelle intervention sur les DCI pourraient toutefois contribuer à réduire encore plus la fréquence des infections.

Cardiac Implantable Electronic Device Infection: Detailed Analysis of Cost Implications.

BACKGROUND: Infections of cardiac implantable electronic devices (CIED) are associated with significant morbidity and mortality. Despite many preventive measures, this condition is associated with significant costs for the health care system. METHODS: We retrospectively analyzed all infection cases referred for lead extraction at a single university hospital over 1 year (2015-2016). We then calculated all costs related to the infection episode per patient using hospital databases and charts review. RESULTS: Thirty-eight patients with CIED infections (29% women-mean age 71 ± 14 years) were referred for lead extraction (27 pocket infections, 11 endocarditis). Devices were mainly pacemakers (60%). When the pathogen was identified, Staphylococcus aureus methicillin sensitive was the main cause. Extraction was performed in all but 3 cases (92%). One death occurred in the nonextracted group. Respective durations of hospitalization and intravenous and antibiotic administration for patients undergoing extraction were 21 and 36 days. The calculated mean total cost for CIED infection management was CAD$29,907 (median: 26,879; range: CAD$4,827-$62,585). Mean hospital charges were CAD$12,291, accounting for 41% of the total costs. CONCLUSIONS: This study represents the first analysis of the direct costs associated with lead extraction in Canada. Device infections are associated with significant costs and increased morbidity. Any preventive measure will have a significant impact on the economic burden of the health care system and patient outcome after lead extraction.

Combined administration of quinidine and propafenone for atrial fibrillation: the CAQ-PAF study.

Propafenone and its 5-hydroxy metabolite exhibit different electrophysiological properties. Objectives of the CAQ-PAF study were (1) to develop a strategy favoring propafenone instead of 5-hydroxypropafenone in plasma following oral administration of propafenone and (2) to evaluate the potential of low-dose quinidine to chronically inhibit CYP2D6. Patients (n = 102) with atrial fibrillation received propafenone 150 mg 3 times daily with either quinidine 100 mg twice daily or placebo. Throughout the study (follow-up, 199 ± 155 days), quinidine successfully inhibited CYP2D6: propafenone concentrations were 3 times higher in patients receiving quinidine (1033 ± 611 ng/mL vs 328 ± 229 ng/mL; P < .001). Moreover, 80% (n = 10) of patients with propafenone levels greater than 1500 ng/mL were in sinus rhythm at 1 year. In contrast, recurrence of atrial fibrillation occurred in 22 of 23 patients with propafenone levels less than 1000 ng/mL (P < .0001). Thus, chronic inhibition of CYP2D6 is achievable with low-dose quinidine in humans. Increased plasma levels of propafenone may be highly beneficial to prevent recurrence of atrial fibrillation.

Catheter ablation for cardiac arrhythmias: a 14-year experience with 5330 consecutive patients at the Quebec Heart Institute, Laval Hospital.

BACKGROUND: Catheter ablation is a curative treatment with excellent success and minimal complication rates for patients with supraventricular or ventricular arrhythmias. METHODS: The acute outcomes and complications of all catheter ablation procedures for supraventricular and ventricular arrhythmias performed at the Quebec Heart Institute (Sainte-Foy, Quebec) during a 14-year period from January 1, 1993, to December 31, 2006, were prospectively assessed. The ablation procedures were classified according to the arrhythmias induced using standard electrophysiological techniques and definitions. Immediate success and complication rates were prospectively included in the database. RESULTS: A total of 5330 patients had catheter ablation performed at the Institute during the period assessed. The mean (+/- SD) age of patients was 50 +/- 18 years (range four to 97 years), and 2340 patients (44%) were men. Most of the patients were younger than 75 years (group 1), and 487 (9%) were 75 years of age and older (group 2). Indications for ablations were as follows: atrioventricular nodal re-entry tachycardia (AVNRT) in 2263 patients, accessory pathways in 1147 patients, atrioventricular node ablation in 803 patients, typical atrial flutter in 377 patients and atrial tachycardia in 160 patients; 580 patients had other ablation procedures. The overall success rates were 81% for atrial tachycardia, 92% for accessory pathways or flutter, and 99% for AVNRT or atrioventricular node ablation. There was no difference in the success rates of the younger (group 1) and older (group 2) patients. Seventy-seven patients (1.4%) had complications, including 11 major events (myocardial infarction in one patient, pulmonary embolism in three patients and permanent pacemaker in seven patients). In patients undergoing AVNRT ablation, two had a permanent pacemaker implanted immediately after the procedure and three had a permanent pacemaker implanted at follow-up. CONCLUSIONS: The results confirm that radiofrequency ablation is safe and effective, supporting ablation therapy as a first-line therapy for the majority of patients with cardiac arrhythmias.

The Brugada syndrome in Canada: a unique French-Canadian experience.

UNLABELLED: The Brugada syndrome (BS) is a clinical entity involving cardiac sodium channelopathy, typical electrocardiogram (ECG) changes and predisposition to ventricular arrhythmia. This syndrome is mainly recognized by specialized cardiologists and electrophysiologists. Data regarding BS largely come from multicentre registries or Asian countries. The present report describes the Quebec Heart Institute experience, including the clinical characteristics and prognosis of native French-Canadian subjects with the Brugada-type ECG pattern. METHODS AND RESULTS: BS has been diagnosed in 35 patients (mean age 51 +/- 12 years) at the Quebec Heart Institute since 2001. Patients were referred from primary care physicians for ECG abnormalities, syncope or ventricular arrhythmia, or were diagnosed incidentally on an ECG obtained for other purposes. The abnormal ECG was recognized after a syncopal spell in four patients and during family screening in four patients. All of the others were incidental findings following a routine ECG. No patient had a family history of sudden cardiac death at younger than 45 years of age. In this population, right bundle branch block pattern with more than 2 mm ST segment elevation in leads V1 to V3 was recorded spontaneously in 25 patients and was induced by sodium blockers in 10 patients. The sodium channel blocker test was performed in 21 patients and was positive in 18 patients (86%). An electrophysiological study was performed in 20 of 35 patients, during which ventricular fibrillation was induced in five patients; three of the five patients were previously asymptomatic. An implantable cardioverter-defibrillator was implanted in six of 35 patients (17%), including three of four patients with a history of syncope. A loop recorder was implanted in three patients. After a mean follow-up of 36 +/- 18 months, one patient died from a noncardiac cause and one patient (with a history of syncope) received an appropriate shock from his implantable cardioverter-defibrillator. No event occurred in the asymptomatic population. CONCLUSIONS: BS is present in the French-Canadian population and is probably under-recognized. Long-term prognosis of individuals with BS, especially in sporadic, asymptomatic cases, needs to be clarified.

Prediction of the recurrence of atrial fibrillation after cardioversion in the Atrial Fibrillation Follow-up Investigation of Rhythm Management (AFFIRM) study.

BACKGROUND: The early recurrence of atrial fibrillation (AF) after cardioversion and the need for frequent cardioversions to maintain sinus rhythm are important clinical features of AF management. METHODS: We evaluated patients in the AFFIRM study whose qualifying episode of AF lasted > or = 48 hours and was terminated by cardioversion. Clinical, electrocardiographic, and echocardiographic risk factors associated with AF recurrence within 2 months of cardioversion and > or = 2 cardioversions during the first year were identified using multivariate analysis in 1293 eligible patients. RESULTS: The risk factors for the recurrence of AF within 2 months of cardioversion were no coronary artery disease and an electrocardiographic lead II P-wave duration of > 135 milliseconds. In the subset of patients not taking antiarrhythmic drug therapy, the multivariate risk factors were no coronary artery disease, second or greater episode of AF, left ventricular ejection fraction < 0.50, and mitral valve thickening. Significant risk factors for the need for > 2 cardioversions in the first year in patients taking antiarrhythmic medication were left atrial diameter > 4.5 cm and mitral valve thickening. The overall sensitivity and specificity of these parameters for recurrence and repeated cardioversion are low. CONCLUSION: There are several risk factors for difficulty maintaining sinus rhythm after cardioversion of persistent AF. The clinical predictive value of these factors is low, and they probably should not be used to justify withholding rhythm control efforts in patients who might benefit from sinus rhythm.

Comparison of management patterns and clinical outcomes in patients with atrial fibrillation in Canada and the United States (from the analysis of the Atrial Fibrillation Follow-up Investigation of Rhythm Management [AFFIRM] database).

Little is known about differences in practice patterns or outcomes in the management of patients who have atrial fibrillation in Canada compared with those in the United States (US). We evaluated the effect that the country of enrollment may have on the management patterns and clinical outcomes in patients who participated in the AFFIRM study. Three thousand four hundred patients came from the US and 660 from Canada. In the US, patients were more likely to have a history of coronary artery disease (39% vs 35%, p = 0.03), hypertension (72% vs 67%, p = 0.01), or congestive heart failure (24% vs 18%, p = 0.0002). More US participants were <65 years of age (25% vs 19%, p = 0.003). Although at randomization the use of warfarin was comparable, during follow-up Canadians were more likely to be treated with warfarin and to be therapeutically anticoagulated. Mortality rate at 5 years was higher in US patients (24% vs 16%, p = 0.001), and the composite end point (death, disabling stroke, major bleeding, cardiac arrest, or anoxic encephalopathy) was also higher in US patients (30% vs 22%, p = 0.0005). Even after adjusting for known differences in baseline characteristics, the risk of death was lower in Canada (hazard ratio 0.70, p = 0.02). In conclusion, in the AFFIRM study, US subjects were more likely to have preexisting cardiovascular diseases despite being younger (<65 years old) than those in Canada. Effective warfarin therapy was more commonly employed in Canada. After correcting for the known differences in baseline characteristics, Canadian patients who had atrial fibrillation had a lower mortality risk.