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Objectives: A remote quality assurance and improvement protocol for point‐of‐care obstetric ultrasound in low‐resource areas was validated against the standard of care for obstetric ultrasound in the United States. Methods: Compressed movie clip ultrasound images (obstetric sweep protocol) obtained by minimally trained personnel were read and interpreted by physicians with training in obstetric ultrasound. Observed findings were compared among readers and between each reader and the gold standard ultrasound scan report. Descriptive statistics were used for the analysis. Results: The agreements among readers and between readers and the gold standard, for the anterior and posterior variables of the placental location were excellent, with Cohen κ values of 0.81 to 0.88 and 0.77 to 0.9, respectively. Cohen κ values were slight or slight/fair for other placental locations (left, right, fundal, and low), and the sensitivity and specificity ranged widely. The agreement among readers and between readers and the gold standard for fetal number comparisons was also excellent, with Cohen κ values ranging from 0.82 to 1, sensitivity from 0.83 to 1, and specificity from 0.99 to 1. The agreement among readers for fetal presentation comparisons, according to the Cohen κ, ranged from 0.79 to 0.85 and between readers and the gold standard had values of 0.43 to 0.49. For biometric parameters and estimated gestational age calculations based on these parameters, inter‐reader reliability ranged from 0.79 to 0.85 for all parameters except femur length. Greater than 94% of obstetric sweep protocol ultrasound ages were within 7 days of the corresponding gold standard age. Conclusions: Movie clip ultrasound images provided adequate information for remote readers to reliably determine the placental location, fetal number, fetal presentation, and pregnancy dating. [ABSTRACT FROM AUTHOR]

Background: Transcatheter aortic valve replacement (TAVR) is being increasingly performed in patients with severe aortic stenosis. Despite newer generation valves, atrioventricular (AV) conduction disturbance is a common complication, necessitating permanent pacemaker (PPM) implantation in about 10% of patients. Hence, it is imperative to improve periprocedural risk stratification to predict PPM implantation after TAVR. The objective of this study was to externally validate a novel risk‐stratification model derived from the National Inpatient Sample (NIS) database that predicts risk of PPM from TAVR. Methods: Components of the score included pre‐TAVR left and right bundle branch block, sinus bradycardia, second‐degree AV block, and transfemoral approach. The scoring system was applied to 917 patients undergoing TAVR at our institution from November 2011 to February 2017. We assessed its predictive accuracy by looking at two components: discrimination using the C‐statistic and calibration using the Hosmer‐Lemeshow goodness of fit test. Results: Ninety patients (9.8%) required PPM. The scoring system showed good discrimination with C‐statistic score of 0.6743 (95% CI: 0.618‐0.729). Higher scores suggested increased PPM risk, that is, 7.3% with score ⩽3, 19.23% with score 4‐6, and 37.50% with score ≥7. Patients requiring PPM were older (81.4 versus 78.7 years, P =.002). Length of stay and in‐hospital mortality was significantly higher in PPM group. Conclusions: The NIS database derived PPM risk prediction model was successfully validated in our database with acceptable discriminative and gradation capacity. It is a simple but valuable tool for patient counseling pre‐TAVR and in identifying high‐risk patients. [ABSTRACT FROM AUTHOR]

Examines the use of mexiletine in treating patients with ventricular fibrillation or clinically documented or induced sustained ventricular tachycardia. Comparison of the efficacy of mexiletine with quinidine in the treatment of chronic ventricular ectopy; Identification of the clinical variables that will predict a successful outcome to drug therapy; Efficacy rate of mexiletine in the treatment of patients with sustained tachycardia when serial electrophysiology testing is employed as part of evaluation.

Adenosine has been used to diagnose latent preexcitation in patients with the Wolff-Parkinson-White syndrome. A case is reported in which intermittent preexcitation had been previously observed, however only retrograde accessory pathway conduction was documented at the time of invasive electrophysiological study. Administration of intravenous adenosine during sinus rhythm resulted in provocation of orthodromic atrioventricular reentry tachycardia. [ABSTRACT FROM AUTHOR]

To study the characteristics of the ventriculoatrial conduction system in patients capable of rapid antegrade atrioventricular conduction, electrophysiologic studies were performed in 23 subjects capable of 1:1 atrioventricular conduction at atrial cycle lengths ≤ 300 ms (Group I), and in 23 subjects with normal 1:1 atrioventricular conduction (Group II). During ventricular pacing, ventriculoatrial block at all cycle lengths was seen in 5/23 (22%) in Group I and in 7/23 (30%) in Group II patients (p = NS). In the remainder, the minimum ventricular pacing cycle length maintaining 1:1 ventriculoatrial conduction was 359 ± 85 ms in Group I, compared to 444 ± 118 ms in Group II (p < .02). Both flat and exponential VA conduction interval curves, drawn as a function of pacing cycle length, were observed in both groups. Discontinuous ventriculoatrial conduction curves were seen in 5/18 (28%) Group I and 1/16 (6%) Group II patients (p = NS). In conclusion, retrograde ventriculoatrial conduction, when present in patients capable of rapid 1:1 atrioventricular conduction, is maintained at shorter cycle lengths than in patients with normal atrioventricular conduction. Quantitative, rather than qualitative, differences distinguish the two groups. [ABSTRACT FROM AUTHOR]

The article discusses the case of an 82-year-old woman with atrial tachyarrhythmia that explores the ideal site for successful catheter ablation. An ablation catheter was placed at the cavotricuspid isthmus, and pacing at 300 ms was done at this site to entrain the tachycardia. For the phenomenon of termination of a reentrant arrhythmia with a stimulus without manifest capture and nonpropagation to occur, the pacing electrode must be in a critical protected location of the tachycardia circuit.