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An efficient electrocardiogram (ECG) delineation algorithm is proposed to instantaneously delineate the ECG characteristic points, such as peak, onset and offset points of QRS, P and T waves. It is essential to delineate the ECG characteristic waves accurately and precisely as it ensure the performance of ECG analysis and diagnosis. The proposed delineation algorithm is based on discrete wavelet transform (DWT) and moving window average (MWA) techniques. The proposed delineation algorithm is evaluated and assessed with the annotation data of QT database in term of accuracy, sensitivity and positive predictive value. With the only available 13 sets QT database records with modified Lead II data, the proposed algorithm achieved significant P peak, R peak, T peak and T offset delineation performance with the accuracy of 95. 34%, 99.80%, 90.82% and 86.33% respectively when evaluated with q1c annotation file. The mean difference between detected and annotated T offset based on q1c and q2c is 13 ms and 3.6 ms respectively. The delineation of 15 minute-long ECG record only required 74.702 second. As conclusion, the proposed ECG delineation algorithm based on DWT and MWA techniques have been proven simple, efficient and accurate in delineating the significant ECG characteristic points.

Purpose/Objective(s): Body Mass Index (BMI) is a parameter used by the World Health Organization and American Cancer Society (ACS) to categorize patient health. Stereotactic Body Radiation Therapy (SBRT) is a standard treatment option for men with localized prostate cancer. Previous studies have described a lower volume of anterior perirectal and mesorectal fat in individuals with lower BMI's. This study assesses the incidence, dosimetric impact, and clinical implications of low BMI on patients treated with prostate SBRT. Materials/Methods: 2421 patients with prostate cancer and for whom BMI's were available were treated at an academic institution with noncoplanar SBRT. Intrarectal amifostine was administered prior to each fraction. The mean age was 67.5 (41-93) years and the mean pre-treatment PSA was 7.55ng/ml (0.33-82.49). Patients were treated for low (23.4%), favorable intermediate (26.7%), unfavorable intermediate (41.3%), and high risk (8.6%) disease. Most (89.1%) patients were treated with a dose of 3500cGy (3500-3625) over 5 fractions. Androgen deprivation Therapy (ADT) was prescribed in 17.2% of cases. Proctitis was scored by RTOG late toxicity scale. The Pearson chi-square test was used to compare patient groupings. Freedom from grade 2+ proctitis was assessed using the Kaplan-Meier method and analyzed using Cox regression. Results: The mean BMI in this series was 28.7 kg/m2 (15.2-58.8). Per ACS stratification, 19.6% of patients were normal weight, while 46.1% and 34.0% of patients were overweight and obese, respectively. 24 (1.0%) patients registered a BMI of 20 kg/m2. These patients were more likely to have T2b/T2c stage disease (30.4% vs. 12.7%, p Z .039), but were without any difference in initial PSA, Gleason score, or NCCN risk grouping. They were more likely to have a pre-existing diagnosis of HIV (9.5% vs. 0.9%, p<.0001), with similar utilization of blood thinners. There was no difference in ADT use. Patients with a BMI 20 kg/m2 had smaller CTV sizes (55.9cc's vs. 79.0cc's, p Z .002), with a higher Rectal V3600 (1.13cc's vs. 0.69cc's, p Z .018). There was no difference in bladder dosimetry. They had a higher 6-year cumulative risk of grade 2+ (11.9% vs. 3.0%, p Z .002) and grade 3+ (5.6% vs. 0.9%, p Z .011) proctitis. There was no difference in bladder outcomes. On multivariate analysis, receiving treatment with a BMI 20 kg/m2 (OR 7.68, CI 1.53-38.50, p Z .013) and using anti-coagulation use during SBRT (OR 4.16, CI 1.89-9.19, p<.0001) were the lone predictors for grade 2+ proctitis. Conclusion: Long-term rates of proctitis are low in patients receiving prostate SBRT. In a large institutional series, those with BMI 20 kg/m2 had an increased risk of grade 2+ and grade 3+ rectal toxicity. The association of lower BMI with higher rectal dosimetry might be a function of decreased perirectal fat. This data is thought provoking and might suggest patient groupings which may derive the greatest benefit to hydrogel placement prior to prostate SBRT.

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This paper presents a literature review of ventricular tachyarrhythmias (VTAs) prediction methods and its prognostic features, as well as highlights the severity of the cardiovascular diseases in general population. This article provides the collective review of the short-term VTAs prediction based on the machine learning methods associated with the potential prognostics electrocardiogram (ECG) characteristics features that have been proposed in the recent literature. The basic morphology of the ECG waveform and its working principle is also briefly described for better understanding of the relationship between the ECG characteristics features and the occurrence of VTAs. In addition, the trend and future direction in the development of VTAs prediction system with machine learning are presented as well. It is desired that the progressive development of real-time, low computational cost and reliable short-term VTAs prediction algorithm in coming years could decrease the mortality rate of cardiovascular diseases within general populations. This article can be adopted as an initial idea and guidelines for beginners in this field to initiate their research.