Safety of catheter ablation for atrial fibrillation in the octogenarian population.

INTRODUCTION: Catheter ablation (CA) has been shown to be an effective treatment for atrial fibrillation (AF). The complication rates and outcomes among octogenarians remain poorly studied. We aimed to compare trends, morbidity, and mortality associated with CA for AF among octogenarians versus those less than 80 years old. METHODS: Using weighted sampling from the National Inpatient Sample database, we identified patients with a primary diagnosis of AF and a primary procedure of CA (2004-2013). Our primary outcome was mortality. Secondary outcomes included incidence of major and minor complications. RESULTS: Among 86,119 patients who underwent CA for AF, 3,482 were 80 years old or older. Complications were significantly more frequent in octogenarians; [16.2% (564 of 3,482) versus 9.8% (8,092 of 82,637), P < 0.001]. Of note, there was no significant difference for the composite of major complications; [3.6% (124 of 3482) in octogenarians versus 2.8% (2286 of 82637), P = 0.20]. The total mortality rate was not significant in a multivariate regression analysis (odds ratio [OR], 0.96; 95% confidence interval [CI], 0.35-2.64; P = .94). The presence of chronic renal failure (OR, 4.19; 95% CI, 2.75-6.36; P < 0.001), anemia (OR, 1.75; 95% CI, 1.03-2.97; P = .04), and chronic pulmonary disease (OR, 1.75; 95% CI, 1.11-2.62; P = .015) were predictors of major complications in octogenarians. CONCLUSION: Catheter ablation for AF in octogenarians does not confer a higher mortality risk than in those less than 80 years old. The procedure is associated with a higher rate of overall complications but there was no difference in terms of major complications or death. The presence of anemia, CKD or pulmonary disease were predictors of major complications in octogenarians.

Atrioventricular dyssynchrony from empiric device settings is common in cardiac resynchronization therapy and adversely impacts left ventricular morphology and function.

BACKGROUND: Echocardiographic atrioventricular (AV) optimization after cardiac resynchronization therapy (CRT) is uncommon due to time constraints and the use of vendor-specific device algorithms. It remains unclear whether optimization of mitral inflow velocities can still be useful. We aimed to investigate post implantation left ventricular (LV) inflow patterns to determine the incidence of AV dyssynchrony from empirically set devices. METHODS: This was a retrospective study of patients undergoing CRT using empiric device settings. Forty-eight patients with clinical, echocardiographic, and pacemaker follow-up were grouped by their post implantation LV filling pattern. Baseline characteristics and echocardiographic measurements were compared with post implantation findings at median 6.3 months (interquartile range [IQR], 3.9-17.0). RESULTS: Twenty-four patients demonstrated AV dyssynchrony (Group 1) after CRT, and 24 patients did not (Group 2). Group 1 patients had less LV reverse remodeling compared to Group 2 patients (ΔLV end-diastolic volume: -3.6 mL vs -49.5 mL, P<.05; ΔLV end-systolic volume: -16.9 mL vs -53.5 mL, P<.05) and did not experience significant improvements in LV outflow tract velocity time integral, stroke volume, or LV ejection fraction. There were no differences in new-onset atrial fibrillation, heart failure readmissions, or mortality between groups. CONCLUSION: Our study suggests that up to 50% of patients with empiric device settings have AV dyssynchrony at 6 months despite atrioventricular delay optimization (AVO) algorithms. As AV dyssynchrony is common and has proven to be modifiable, a strategic approach to Doppler echocardiography-guided AVO after CRT is warranted, particularly in nonresponders where the LV filling pattern is fused or truncated.

Simulations of gravitational stress on normovolemic and hypovolemic men and women.

BACKGROUND: Earth-based simulations of physiologic responses to space mission activities are needed to develop prospective countermeasures. To determine whether upright lower body positive pressure (LBPP) provides a suitable space mission simulation, we investigated the cardiovascular responses of normovolemic and hypovolemic men and women to supine and orthostatic stress induced by head-up tilt (HUT) and upright LBPP, representing standing in lunar, Martian, and Earth gravities. METHODS: Six men and six women were tested in normovolemic and hypovolemic (furosemide, intravenous, 0.5 mg x kg(-1)) conditions. Continuous electrocardiogram, blood pressure, segmental bioimpedance, and stroke volume (echocardiography) were recorded supine and at lunar, Martian, and Earth gravities (10 degrees, 20 degrees, and 80 degrees HUT vs. 20%, 40%, and 100% bodyweight upright LBPP), respectively. Cardiovascular responses were assessed from mean values, spectral powers, and spontaneous baroreflex parameters. RESULTS: Hypovolemia reduced plasma volume by approximately 10% and stroke volume by approximately 25% at supine, and increasing orthostatic stress resulted in further reductions. Upright LBPP induced more plasma volume losses at simulated lunar and Martian gravities compared with HUT, while both techniques induced comparable central hypovolemia at each stress. Cardiovascular responses to orthostatic stress were comparable between HUT and upright LBPP in both normovolemic and hypovolemic conditions; however, hypovolemic blood pressure was greater during standing at 100% bodyweight compared to 80 degree HUT due to a greater increase of total peripheral resistance. CONCLUSIONS: The comparable cardiovascular response to HUT and upright LBPP support the use of upright LBPP as a potential model to simulate activity in lunar and Martian gravities.

Response to cardiac resynchronization therapy in non-ischemic cardiomyopathy is unrelated to medical therapy.

INTRODUCTION: Current guidelines recommend at least 3 months of guideline-directed medical therapy (GDMT) for patients with a new onset of non-ischemic cardiomyopathy (NICM) and left bundle branch block (LBBB) prior to cardiac resynchronization therapy (CRT). For patients who do not receive optimal GDMT, response to CRT is unknown. METHODS: Patients with NICM and LBBB with QRS ≥ 120 ms were identified among all patients who underwent CRT. Patients who received GDMT for ≥ 3 months before CRT were compared to those who did not. Among 38 patients who met inclusion criteria, 24 received optimal GDMT prior to implantation (Group 1) and 14 did not (Group 2). RESULTS: QRS narrowing occurred in Group 1 (160 ± 9 ms to 138 ± 20 ms, P = 0.001) and Group 2 (160 ± 17 ms to 139 ± 30 ms, P = 0.021). Left ventricular ejection fraction (LVEF) improvement occurred in Group 1 (21.3 ± 5.9% to 34.4 ± 13.9%, P < 0.001) and Group 2 (18.8 ± 4.7% to 31.1 ± 13%, P = 0.010). QRS interval and LVEF changes were similar between groups (P = NS). There was a trend towards greater CRT response in women than in men, although differences did not reach statistical significance. CONCLUSION: In patients with NICM and LBBB, CRT is associated with improvements in LV size and function independent of prior GDMT. The ability of resynchronization to improve LVEF without GDMT suggests that CRT without waiting 3 months for GDMT optimization may benefit some patients with NICM and LBBB.

Multi-morbidity burden, psychological distress, and quality of life in implantable cardioverter defibrillator recipients: Results from a nationwide study.

BACKGROUND: The prevalence of multi-morbidity in implantable cardioverter defibrillator (ICD) recipients is approximately 25%. Multi-morbidity is associated with poor health and psychological outcomes in this population and may affect ICD recipients' quality-of-life (QOL). The purpose of this study was to determine the prevalence of psychological distress (anxiety, depressive symptoms, and Type-D personality) in ICD recipients with varying levels of comorbidities, and to examine the association between multi-morbidity burden and QOL in this population. METHODS: All adults listed in the Swedish ICD and Pacemaker Registry in 2012 with an ICD implanted for at least one year were invited to participate in this study. Binary logistic regression was used to predict QOL using the EQ-5D mean index dichotomized based on median QOL scores. Multi-morbidity burden scores were based on quartile groupings. RESULTS: A total of 2658 ICD recipients participated in the study (with a mean age of 65, 20.6% female, mean implant duration of 4.7 years, with 35.4% implanted for primary prevention of sudden cardiac arrest). Greater multi-morbidity burden, female sex, not working outside the home, history of ICD shock, negative ICD experience, higher levels of ICD-related concerns, and the presence of anxiety, depression, or Type D personality were associated with worse QOL in ICD recipients. Predictors differed by multi-morbidity burden level. CONCLUSIONS: Multi-morbidity burden and psychological distress is an essential factor related to QOL. This issue should be discussed with potential ICD recipients prior to implant. Further exploration of increased recognition and treatment of psychological distress in ICD recipients is warranted.

Missed opportunities! End of life decision making and discussions in implantable cardioverter defibrillator recipients.

BACKGROUND: Recent guidelines highlight the need for clinician-patient discussions regarding end-of-life (EOL) choices prior to implantable cardioverter defibrillator (ICD) implantation. Health literacy could affect the quality and quantity of such discussions. OBJECTIVE: Our objective was to determine the association of health literacy with experiences, attitudes, and knowledge of the ICD at EOL. METHODS: In this cross-sectional study, we used validated instruments to measure health literacy and patient experiences, attitudes, and knowledge of the ICD at EOL. RESULTS: Of the 240 ICD recipients, 76% of participants reported never having discussed the implications of a future withdrawal of defibrillation therapy with their healthcare provider. Increased odds of choosing to maintain defibrillation therapy were associated with female gender and lower ICD knowledge. CONCLUSIONS: From patients' perspectives, EOL discussions with providers were minimal. Most patients hold misperceptions about ICD function that could interfere with optimal EOL care, particularly for those with inadequate health literacy.

Short- and long-term success of substrate-based mapping and ablation of ventricular tachycardia in arrhythmogenic right ventricular dysplasia.

BACKGROUND: Multiple morphologies, hemodynamic instability, or noninducibility may limit ventricular tachycardia (VT) ablation in patients with arrhythmogenic right ventricular dysplasia (ARVD). Substrate-based mapping and ablation may overcome these limitations. We report the results and success of substrate-based VT ablation in ARVD. METHODS AND RESULTS: Twenty-two patients with ARVD were studied. Traditional mapping for VT was limited because of multiple/changing VT morphologies (n=14), nonsustained VT (n=10), or hemodynamic intolerance (n=5). Sinus rhythm CARTO mapping was performed to define areas of "scar" (<0.5 mV) and "abnormal" myocardium (0.5 to 1.5 mV). Ablation was performed in "abnormal" regions, targeting sites with good pace maps compared with the induced VT(s). Linear lesions were created in these areas to (1) connect the scar/abnormal region to a valve continuity or other scar or (2) encircle the scar/abnormal region. Eighteen patients had implanted cardioverter defibrillators, 15 had implanted cardioverter defibrillator therapies, and 7 had sustained VT (6 with syncope). VTs (3+/-2 per patient) were induced (cycle length, 339+/-94 ms), and scar was identified in all patients. Scar areas were related to the tricuspid annulus, proximal right ventricular outflow tract, and anterior/inferior-apical walls. Lesions connected abnormal regions to the annulus (n=12) or other scars (n=4) and/or encircled abnormal regions (n=13). Per patient, a mean of 38+/-22 radiofrequency lesions was applied. Short-term success was achieved in 18 patients (82%). VT recurred in 23%, 27%, and 47% of patients after 1, 2, and 3 years' follow-up, respectively. CONCLUSIONS: Substrate-based ablation of VT in ARVD can achieve a good short-term success rate. However, recurrences become increasingly common during long-term follow-up.