Gender Differences in the Pursuit of Cardiac Electrophysiology Training in North America.

BACKGROUND: Despite the increase in the number of female physicians across most specialties within cardiology, <10% of clinical cardiac electrophysiology (EP) fellows are women. OBJECTIVES: This study sought to determine the factors that influence fellows-in-training (FITs) to pursue EP as a career choice and whether this differs by gender. METHODS: The authors conducted an online multiple-choice survey through the American College of Cardiology to assess the decision factors that influence FITs in the United States and Canada to pursue cardiovascular subspecialties. RESULTS: A total of 933 (30.5%) FITs completed the survey; 129 anticipated specializing in EP, 259 in interventional cardiology (IC), and 545 in a different field or were unsure. A total of 1 in 7 (14%) FITs indicated an interest in EP. Of this group, more men chose EP than women (84% vs 16%; P < 0.001). The most important factor that influenced FITs to pursue EP was a strong interest in the field. Women were more likely to be influenced by having a female role model (P = 0.001) compared with men. After excluding FITs interested in IC, women who deselected EP were more likely than men to be influenced by greater interest in another field (P = 0.004), radiation concerns (P = 0.001), lack of female role models (P = 0.001), a perceived "old boys' club" culture (P = 0.001) and discrimination/harassment concerns (P = 0.001). CONCLUSIONS: Women are more likely than men to be negatively influenced by many factors when it comes to pursuing EP as a career choice. Addressing those factors will help decrease the gender disparity in the field.

Intracardiac electrogram T-wave alternans/variability increases before spontaneous ventricular tachyarrhythmias in implantable cardioverter-defibrillator patients: a prospective, multi-center study.

BACKGROUND: T-wave alternans (TWA) increases before ventricular tachycardia (VT) or fibrillation (VF), suggesting that it may warn of VT/VF in implantable cardioverter-defibrillator patients. Recently, we described a method for measuring alternans and nonalternans variability (TWA/V) from electrograms (EGMs) stored in implantable cardioverter-defibrillators before VT/VF. The goal of this prospective, multicenter study was to determine whether EGM TWA/V was greater before VT/VF than at baseline. METHODS AND RESULTS: We enrolled 63 implantable cardioverter-defibrillator patients. TWA/V was computed from stored EGMs before spontaneous VT/VF and from sequential windows of 8 pairs of beats using 4 different control recordings: baseline rhythm, rapid pacing at 105 bpm, segments of ambulatory Holter EGMs matched to the time of VT/VF episodes, and EGMs before spontaneous supraventricular tachycardia. During follow-up, 28 patients had 166 episodes of VT/VF. TWA/V was greater before VT/VF (62.9 ± 3.1 µV; n = 28) than during baseline rhythm (12.8 ± 1.8 µV; P < 0.0001; n = 62), during rapid pacing (14.5 ± 2.0 µV; P < 0.0001; n = 52), before supraventricular tachycardia (27.5 ± 6.1 µV; P < 0.0001; n = 9), or during time-matched ambulatory controls (12.3 ± 3.5 µV; P < 0.0001; n = 16). By logistic regression, the odds of VT/VF increased by a factor of 2.2 for each 10-µV increment in TWA/V (P < 0.0001). CONCLUSIONS: In implantable cardioverter-defibrillator patients, EGM TWA/V is greater before spontaneous VT/VF than in control recordings. Future implantable cardioverter-defibrillators that measure EGM TWA/V continuously may warn patients and initiate pacing therapies to prevent VT/VF.

Single diagnostic pacing maneuver for supraventricular tachycardia.

BACKGROUND: Diagnostic supraventricular tachycardia (SVT) features and pacing maneuvers tend to be specific but insensitive. Therefore, diagnosis often requires the integration of multiple pieces of information and/or pacing maneuvers, which adds to the complexity of catheter ablation procedures. OBJECTIVE: The purpose of this study was to determine if a single diagnostic pacing maneuver, namely, ventricular overdrive pacing including a basal pacing site near the earliest atrial activation, provides a definitive SVT diagnosis in nearly all patients. METHODS: Sixty-seven consecutive patients with SVT undergoing catheter ablation at two institutions were prospectively studied. RESULTS: Overdrive ventricular pacing provided the correct diagnosis in 91% of all patients and in 100% of patients when pacing accelerated the atrium to the pacing cycle length. Fusion due to wavefront collision in the ventricles or distal conduction system was 73% sensitive and 100% specific for accessory pathway-mediated SVT. Basal pacing was superior to pacing from the right ventricular apex for distinguishing accessory pathway-mediated SVT from AV nodal reentrant tachycardia. CONCLUSION: Overdrive ventricular pacing is a highly effective single diagnostic pacing maneuver for sustained SVT. Basal pacing sites near the earliest atrial activation are superior to the right ventricular apex.

Clinical and electrophysiologic predictors of ventricular tachyarrhythmia recurrence in patients with implantable cardioverter defibrillators.

INTRODUCTION: Not all patients experience recurrent sustained ventricular tachyarrhythmias after placement of an implantable cardioverter defibrillator (ICD). We evaluated the clinical and electrophysiologic predictors of ventricular tachycardia (VT) and ventricular fibrillation (VF) recurrence following ICD implantation. METHODS AND RESULTS: Consecutive patients (n = 133) underwent 4 +/- 3 serial electrophysiologic studies (EPS) over 50 +/- 26 months following ICD implantation. Sustained VT/VF could always be induced during follow-up EPS in 49 patients; sustained VT/VF was sometimes induced during follow-up EPS in 47 patients; and sustained VT/VF could never be induced during follow-up EPS in 37 patients. Spontaneous VT/VF requiring ICD therapy occurred in 107 patients during follow-up. Patients with sustained VT/VF that was always inducible or sometimes inducible during follow-up experienced more frequent episodes of VT/VF following ICD implant (20.5, 95% CI 12.7-33.0; and 17.8, 95% CI 11.3-28.1 episodes/patient respectively; vs 3.0, 95% CI 2.0-4.6 episodes/patient for patients with VT/VF never induced, P < 0.001). Inducibility of sustained VT/VF post-ICD implant (P < 0.001) and sustained VT as the presenting arrhythmia (P = 0.02) were independent predictors of spontaneous VT/VF recurrence. CONCLUSION: Reproducibly inducible VT/VF following ICD implantation predicts a high probability of VT/VF recurrence and identifies a cohort of patients who experience frequent episodes of VT/VF over time. Persistent noninducibility of sustained VT/VF identifies a group of patients who experience no or very few episodes of VT/VF recurrence.