Vaibhav R. Vaidya

Stroke or transient ischemic attack in patients with transvenous pacemaker or defibrillator and echocardiographically detected patent foramen ovale

Background— A patent foramen ovale (PFO) may permit arterial embolization of thrombi that accumulate on the leads of cardiac implantable electronic devices in the right-sided cardiac chambers. We sought to determine whether a PFO increases the risk of stroke/transient ischemic attack (TIA) in patients with endocardial leads. Methods and Results— We retrospectively evaluated all patients who had endocardial leads implanted between January 1, 2000, and October 25, 2010, at Mayo Clinic Rochester. Echocardiography was used to establish definite PFO and non-PFO cohorts. The primary end point of stroke/TIA consistent with a cardioembolic etiology and the secondary end point of mortality during postimplantation follow-up were compared in PFO versus non-PFO patients with the use of Cox proportional hazards models. We analyzed 6075 patients (364 with PFO) followed for a mean 4.7±3.1 years. The primary end point of stroke/TIA was met in 30/364 (8.2%) PFO versus 117/5711 (2.0%) non-PFO patients (hazard ratio, 3.49; 95% confidence interval, 2.33–5.25; P<0.0001). The association of PFO with stroke/TIA remained significant after multivariable adjustment for age, sex, history of stroke/TIA, atrial fibrillation, and baseline aspirin/warfarin use (hazard ratio, 3.30; 95% confidence interval, 2.19–4.96; P<0.0001). There was no significant difference in all-cause mortality between PFO and non-PFO patients (hazard ratio, 0.91; 95% confidence interval, 0.77–1.07; P=0.25). Conclusions— In patients with endocardial leads, the presence of a PFO on routine echocardiography is associated with a substantially increased risk of embolic stroke/TIA. This finding suggests a role of screening for PFOs in patients who require cardiac implantable electronic devices; if a PFO is detected, PFO closure, anticoagulation, or nonvascular lead placement may be considered.

Reversing anticoagulant effects of novel oral anticoagulants: role of ciraparantag, andexanet alfa, and idarucizumab

Novel oral anticoagulants (NOACs) are increasingly used in clinical practice, but lack of commercially available reversal agents is a major barrier for mainstream use of these therapies. Specific antidotes to NOACs are under development. Idarucizumab (aDabi-Fab, BI 655075) is a novel humanized mouse monoclonal antibody that binds dabigatran and reverses its anticoagulant effect. In a recent Phase III study (Reversal Effects of Idarucizumab on Active Dabigatran), a 5 g intravenous infusion of idarucizumab resulted in the normalization of dilute thrombin time in 98% and 93% of the two groups studied, with normalization of ecarin-clotting time in 89% and 88% patients. Two other antidotes, andexanet alfa (PRT064445) and ciraparantag (PER977) are also under development for reversal of NOACs. In this review, we discuss commonly encountered management issues with NOACs such as periprocedural management, laboratory monitoring of anticoagulation, and management of bleeding. We review currently available data regarding specific antidotes to NOACs with respect to pharmacology and clinical trials.

Electrophysiologic Characteristics of Ventricular Arrhythmias Arising From the Aortic Mitral Continuity - Potential Role of the Conduction System

Catheter ablation of ventricular arrhythmia (VA) at the fibrous aortic mitral continuity (AMC) has been described, yet the nature of the arrhythmogenic substrate remains unknown.

Catheter ablation related mitral valve injury: the importance of early recognition and rescue mitral valve repair.

An increasing number of catheter ablations involve the mitral annular region and valve apparatus, increasing the risk of catheter interaction with the mitral valve (MV) complex. We review our experience with catheter ablation‐related MV injury resulting in severe mitral regurgitation (MR) to delineate mechanisms of injury and outcomes.

Endocavitary structures in the outflow tract: Anatomy and electrophysiology of the Conus Papillary Muscles

Catheter ablation is an increasingly used and successful treatment choice for right ventricular outflow tract (RVOT) arrhythmias. While the role of endocavitary structures and the regional morphology of the ventricular inflow tract and the right atrium as a cause for difficulty with successful ablation are well described, similar issues within the RVOT are not well understood. It is also not commonly appreciated that one of the papillary muscles is located within the proximal RVOT. We report 3 patients in which ventricular arrhythmia was targeted and ablated in the conus papillary muscle. The anatomic features, potential role of the fascicular conduction system, and unique challenges with mapping arrhythmia arising from this structure are discussed.

Pulmonary embolism in patients with transvenous cardiac implantable electronic device leads

BACKGROUND Cardiac implantable electronic devices (CIEDs) are commonly associated with transvenous lead-related thrombi that can cause pulmonary embolism (PE). METHODS AND RESULTS We retrospectively evaluated all patients with transvenous CIED leads implanted at Mayo Clinic Rochester between 1 January 2000, and 25 October 2010. Pulmonary embolism outcomes during follow-up were screened using diagnosis codes and confirmed with imaging study reports. Of 5646 CIED patients (age 67.3 ± 16.3 years, 64% men, mean follow-up 4.69 years) 88 developed PE (1.6%), incidence 3.32 [95% confidence interval (CI) 2.68-4.07] per 1000 person-years [men: 3.04 (95% CI 2.29-3.96) per 1000 person-years; women: 3.81 (95% CI 2.72-5.20) per 1000 person-years]. Other than transvenous CIED lead(s), 84% had another established risk factor for PE such as deep vein thrombosis (28%), recent surgery (27%), malignancy (25%), or prior history of venous thromboembolism (15%). At the time of PE, 22% had been hospitalized for ≥ 48 h, and 59% had been hospitalized in the preceding 30 days. Pulmonary embolism occurred in 22% despite being on systemic anticoagulation therapy. Out of 88 patients with PE, 45 subsequently died, mortality rate 93 (95% CI 67-123) per 1000 person-years (hazard ratio 2.0, 95% CI 1.5-2.7, P < 0.0001). CONCLUSIONS Though lead-related thrombus is commonly seen in patients with transvenous CIED leads, clinical PE occurs with a low incidence. It is possible that embolism of lead thrombus is uncommon or emboli are too small to cause consequential pulmonary infarction.

Outflow Tract Ventricular Tachycardia Mapped to the Coronary Arteries: Anatomical Correlates and Management Strategies

The coronary cusps have been well described as a successful site for ablation in patients with symptomatic outflow tract ventricular tachycardia. The earliest site of activation is rarely found at the ostia or into the main coronary arteries. The exact anatomic substrate, diagnostic characteristics, and therapeutic approaches for such instances are poorly understood.

Burden of Arrhythmia in Pregnancy

Editorial, see p 590 Maternal morbidity and mortality in the United States continues to rise.1 Although supraventricular tachycardia (SVT) is considered the most frequent sustained arrhythmia in pregnancy, atrial fibrillation (AF) and ventricular arrhythmias are described with varying frequencies.2,3 A paucity of data exist regarding temporal trends of frequency and outcomes of arrhythmias in pregnancy-related hospitalizations. In this descriptive observational analysis of pregnancy-related hospitalizations from a large nationwide sample, we describe temporal trends in frequency of arrhythmias, comorbidities associated with arrhythmias, and the frequency of adverse maternal and fetal outcomes. The Agency for Healthcare Research and Quality created the nationwide inpatient sample, which includes discharge data from >1200 hospitals. Each entry comprises hospitalization for a single patient and is associated with a primary discharge diagnosis and up to 24 secondary diagnoses. Multiple prior studies have utilized the nationwide inpatient sample to study various conditions.3,4 The study population comprised all hospital discharges in pregnant women 18 to 50 years of age from January 1, 2000, to December 31, 2012. Discharge codes with pregnancy-related codes (International Classification of Diseases-9 codes 630–648) and delivery-related codes (International Classification of Diseases-9 codes 72–75, v27 and 650–659) were used. According to a previous publication,4 arrhythmias were identified with the following International Classification of Diseases-9 codes: AF 427.31, atrial flutter 427.32, SVT 427.0, ventricular fibrillation 427.41, ventricular flutter 427.42, and VT 427.1. Patients with any of these diagnoses were defined as any arrhythmia. Maternal and fetal adverse …

Ventricular premature contraction associated with mitral valve prolapse

BACKGROUND In patients with frequent premature ventricular contractions (PVCs), little is known about the profile of PVCs and the outcome of treatment in patients with mitral valve prolapse (MVP) compared to those without MVP. METHODS AND RESULTS Patients with documented PVCs between January 2001 and October 2012 were divided into 2 groups: MVP and non-MVP. The PVC characteristics, efficacy of therapy, and outcome were compared between the 2 groups. A total of 112 patients with MVP and 952 without MVP were identified. The frequency of PVCs was similar between the 2 groups (P>.05). In patients who underwent cardiac mapping, PVCs originating in papillary muscles (26.7% vs 2.3%; P<.001) and fascicle (13.3% vs 3.4%; P<.001) were more frequently seen in the MVP group than in the non-MVP group, which raises the difficulty of catheter ablation. The 2 groups had similar response to catheter ablation or medical therapy (P>.05). The survival rate was similar between the 2 groups (P=.95). CONCLUSION In patients with significant PVC burden, MVP patients had similar PVC frequency, treatment outcome, and survival rate to those without MVP.

Compatibility of Electroanatomical Mapping Systems with a Concurrent Percutaneous Axial Flow Ventricular Assist Device

Hemodynamic instability hinders activation and entrainment mapping during ventricular tachycardia ablation. The Impella 2.5 microaxial flow device (MFD; Abiomed Inc., Danvers, MA, USA) is used to prevent hemodynamic instability during electrophysiologic study. However, electromagnetic interference (EMI) generated by this device can preclude accurate electroanatomic mapping.