Mobile Electrocardiogram Monitoring and Health-Related Quality of Life in Patients With Atrial Fibrillation: Findings From the iPhone Helping Evaluate Atrial Fibrillation Rhythm Through Technology (iHEART) Study.

BACKGROUND: Atrial fibrillation (AF) is associated with high recurrence rates and poor health-related quality of life (HRQOL) but few effective interventions to improve HRQOL exist. OBJECTIVE: The aim of this study was to examine the impact of the "iPhone Helping Evaluate Atrial Fibrillation Rhythm through Technology" (iHEART) intervention on HRQOL in patients with AF. METHODS: We randomized English- and Spanish-speaking adult patients with AF to receive either the iHEART intervention or usual care for 6 months. The iHEART intervention used smartphone-based electrocardiogram monitoring and motivational text messages. Three instruments were used to measure HRQOL: the Atrial Fibrillation Effect on Quality of Life (AFEQT), the 36-item Short-Form Health survey, and the EuroQol-5D. We used linear mixed models to compare the effect of the iHEART intervention on HRQOL, quality-adjusted life-years, and AF symptom severity. RESULTS: A total of 238 participants were randomized to the iHEART intervention (n = 115) or usual care (n = 123). Of the participants, 77% were men and 76% were white. More than half (55%) had an AF recurrence. Both arms had improved scores from baseline to follow-up for AFEQT and AF symptom severity scores. The global AFEQT score improved 18.5 and 11.2 points in the intervention and control arms, respectively (P < .05). There were no statistically significant differences in HRQOL, quality-adjusted life-years, or AF symptom severity between groups. CONCLUSIONS: We found clinically meaningful improvements in AF-specific HRQOL and AF symptom severity for both groups. Additional research with longer follow-up should examine the influence of smartphone-based interventions for AF management on HRQOL and address the unique needs of patients diagnosed with different subtypes of AF.

Recurrent atrial fibrillation/flutter detection after ablation or cardioversion using the AliveCor KardiaMobile device: iHEART results.

OBJECTIVE: This study evaluated the impact of daily ECG (electrocardiogram) self-recordings on time to documented recurrent atrial fibrillation (AF) or atrial flutter (AFL) and time to treatment of recurrent arrhythmia in patients undergoing catheter radiofrequency ablation (RFA) or direct current cardioversion (DCCV) for AF/AFL. BACKGROUND: AF recurrence rates after RFA and DCCV are 20% to 45% and 60% to 80%, respectively. Randomized trials comparing mobile ECG devices to standard of care have not been performed in an AF/AFL population after treatment. METHODS: Of 262 patients consented, 238 were randomized to either standard of care (123) or to receive the iHEART intervention (115). Patients in the intervention group were provided with and trained to use an AliveCor KardiaMobile ECG monitor, and were instructed to take and transmit daily ECG recordings. Data were collected from transmitted ECG recordings and patients' electronic health records. RESULTS: In a multivariate Cox model, the likelihood of recurrence detection was greater in the intervention group (hazard ratio = 1.56, 95% confidence interval [CI]: 1.06-2.30, P = .024). Hazard ratios did not differ significantly for RFA and DCCV procedures. Recurrence during the first month after ablation strongly predicted later recurrence (hazard ratio = 4.53, 95% CI: 2.05-10.00, P = .0006). Time from detection to treatment was shorter for the control group (hazard ratio = 0.33, 95% CI: 0.57-2.92, P < .0001). CONCLUSIONS: The use of mobile ECG self-recording devices allows for earlier detection of AF/AFL recurrence and may empower patients to engage in shared health decision-making.

Increased body mass index, age, and left atrial size are associated with altered intracardiac atrial electrograms in persistent atrial fibrillation patients.

BACKGROUND: There are limited studies evaluating whether atrial fibrillation (AF) patients with increased BMI, age, and left atrial (LA) size have altered intracardiac electrogram (EGM) morphology. METHODS: We analyzed left atrial intracardiac EGMs acquired during invasive electrophysiology study in 54 patients with AF. EGM correlations were assessed among AF risk factors including age, left atrial size, and BMI. RESULTS: BMI correlated positively with DF (r2 = 0.17, p = 0.009) and MP (r2 = 0.16, p = 0.01) with dominant frequency (DF) and mean spectral profile (MP) greater among obese individuals. Age was negatively associated with mean amplitude (r2 = 0.42, p < 0.001) and width (r2 = 0.32, p < 0.001); age was positively correlated with MP (r2 = 0.24, p < 0.001). LA size was negatively correlated with mean amplitude (r2 = 0.18, p = 0.03) and width (r2 = 0.23, p = 0.01); LA size was positively correlated with DF (r2 = 0.22, p = 0.01) and MP (r2 = 0.23, p = 0.01). Mean amplitude and width were decreased among subjects with a severely enlarged LA; DF and MP were increased in those with severely enlarged LA. The associations with BMI and LA size remained significant in multiple regression models that included age, male gender, time since AF diagnosis, and LVEF. CONCLUSIONS: EGM morphology of AF patients with increased BMI, older age, and an enlarged LA possessed decreased amplitude and decreased width and increased DF and MP. These findings suggest that atrial remodeling due to increased age, LA size, and BMI is associated with differences in local atrial activation, decreased refractoriness, and more heterogeneous activation. These novel findings point out clinical risk factors for atrial fibrillation that may affect electrogram characteristics.

The use of serial cardiac 18F-fluorodeoxyglucose- positron emission tomography imaging to diagnose, monitor, and tailor treatment of cardiac sarcoidosis patients with arrhythmias: a case series and review.

BACKGROUND: Clinically evident cardiac involvement has been documented in 5% of sarcoidosis patients, primarily manifesting as heart block, ventricular arrhythmias, and heart failure. Heart Rhythm Society consensus guidelines recommend advanced cardiac imaging with fluorodeoxyglucose-positron emission tomography (FDG-PET) scan for diagnosis of cardiac sarcoidosis, given endomyocardial biopsy's low sensitivity. CASE SUMMARY: We describe four patients with cardiac sarcoidosis diagnosed with FDG-PET scan performed using a standardized imaging protocol for cardiac sarcoidosis. Serial FDG-PET scans were performed to monitor disease progression and response to therapy. Patients 1 and 2 presented with heart block, Patient 3 with heart failure and ventricular tachycardia (VT), and Patient 4 with VT. Patient 1 showed an initial decrease in standard uptake value (SUV) on immunosuppression, followed by an increase in SUV, necessitating steroid therapy. Patient 2's SUV decreased on immunosuppression. Patient 3 required 3.5 years of immunosuppression for the SUV to decrease to inactive disease levels, with SUV increasing and decreasing at different times during treatment, and subsequently developed VT. For Patient 4, areas of inflammation on the initial scan matched low voltage areas on the patient's EP study, confirming the arrhythmia's pathophysiological basis. DISCUSSION: Cardiac sarcoidosis progression and response to therapy are heterogeneous. Serial FDG-PET scans are useful to diagnose disease, tailor therapy, and monitor the clinical course of disease, allowing treatment decisions to be based on the quantitative level of inflammation seen on FDG-PET.