Paced P-wave morphology templates to guide atrial tachycardia localization: A derivation and validation study.

BACKGROUND: Surface ECG is a useful tool to guide mapping of focal atrial tachycardia (AT). OBJECTIVES: We aimed to construct 12-lead ECG templates for P-wave morphology (PWM) during endocardial pacing from different sites in both atria in patients with no apparent structural heart disease (derivation cohort), with the goal of creating a localization algorithm, which could subsequently be validated in a cohort of patients undergoing catheter ablation of focal AT (validation cohort). METHODS: We prospectively enrolled consecutive patients who underwent electrophysiology study, had no structural heart disease and no atrial enlargement. Atrial pacing, at twice diastolic threshold, was carried out at different anatomical sites in both atria. Paced PWM and duration were assessed. An algorithm was generated from the constructed templates of each pacing site. The algorithm was applied on a retrospective series of successfully ablated AT patients. Overall and site-specific accuracy were determined. RESULTS: Derivation cohort included 65 patients (25 men, age 37 ± 13 years). Atrial pacing was performed in 1025 sites in 61 patients (95%) in RA and in 15 patients (23%) in LA. The validation cohort included 71 patients (28 men, age 52 ± 19 years). AT were right atrial in 66.2%. The algorithm successfully predicted AT origin in 91.5% of patients (100% in LA and 87.2% in RA). It was off by one adjacent segment in the remaining 8.5%. CONCLUSIONS: A simple ECG algorithm based on paced PWM templates was highly accurate in localizing site of origin of focal AT in patients with structurally normal hearts.

Urgent-start peritoneal dialysis results in fewer procedures than hemodialysis.

BACKGROUND: Peritoneal dialysis (PD) is an underutilized modality for hospitalized patients with an urgent need to start renal replacement therapy in the USA. Most patients begin hemodialysis (HD) with a tunneled central venous catheter (CVC). METHODS: We examined the long-term burden of dialysis modality-related access procedures with urgent-start PD and urgent-start HD in a retrospective cohort of 73 adults. The number of access-related (mechanical and infection-related) procedures for each modality was compared in the first 30 days and cumulatively through the duration of follow-up. RESULTS: Fifty patients underwent CVC placement for HD and 23 patients underwent PD catheter placement for urgent-start dialysis. Patients were followed on average >1 year. The PD group was significantly younger, with less diabetes, with a higher pre-dialysis serum creatinine and more likely to have a planned dialysis access. The mean number of access-related procedures per patient in the two groups was not different at 30 days; however, when compared over the duration of follow-up, the number of access-related procedures was significantly higher in the HD group compared with the PD group (4.6 ± 3.9 versus 0.61 ± 0.84, P < 0.0001). This difference persisted when standardized to procedures per patient-month (0.37 ± 0.57 versus 0.081 ± 0.18, P = 0.019). Infection-related procedures were similar between groups. Findings were the same even after case-matching was performed for age and diabetes mellitus with 18 patients in each group. CONCLUSIONS: Urgent-start PD results in fewer invasive access procedures compared with urgent-start HD long term, and should be considered for urgent-start dialysis.

Anatomical and Functional Retinal Complications of Combined Sofosbuvir and Ribavirin Therapy in Patients With Chronic Hepatitis C Virus.

BACKGROUND AND OBJECTIVE: To evaluate the anatomical and functional retinal complications of combined sofosbuvir and ribavirin therapy in patients with chronic hepatitis C virus (HCV). PATIENTS AND METHODS: Three hundred patients with chronic HCV were recruited for this prospective, observational study from the National Liver Institute of Menoufia University from November 2015 to September 2017. Ophthalmic examination and follow-up were performed in the outpatient clinic of the Ophthalmology Department at Menoufia University. All patients received the same regimen (sofosbuvir and ribavirin) for 6 months. Patients were followed up during the period of treatment (6 months) and for 6 months after treatment completion. Complete ophthalmic examination, fundus fluorescein angiography (FFA) (to detect retinal ischemia), optical coherence tomography (OCT) (to detect retinal nerve fiber layer [RNFL] thickness and central macular thickening), and electroretinogram (ERG) (to detect rod and cone functions) tests were performed before and after treatment completion. RESULTS: The mean age of the patients was 46.17 years ± 11.38 years (range: 20 years to 60 years). The study included 138 men (46%) and 162 women (54%). During follow-up, there were no signs of retinopathy or optic nerve affection. There were also no signs of retinal ischemia (by FFA), RNFL affection, macular edema (by OCT), or rod or cone affection (by ERG). CONCLUSION: Combined treatment (sofosbuvir and ribavirin) may be safe without causing anatomical or functional retinal complications. [Ophthalmic Surg Lasers Imaging Retina. 2019;50:39-42.].