Recent efforts have improved synchronization systems that facilitate timed insemination in beef cattle. However, synchronization systems utilizing a single fixed-time artificial insemination (FTAI) frequently result in 25-40% non-pregnant heifers. The purpose of this study was to determine the effectiveness and define economic parameters of a FTAI resynchronization protocol in beef heifers after synchronization using a 5d CO-Synch + CIDR system. Estrus was synchronized in crossbred heifers (n=176) using 5 d CO-Synch + CIDR with FTAI at 72 h. After the initial AI, open heifers received either resynchronization (RS) or natural service (NS) return service treatments. The RS treatment was diagnosed for pregnancy 29 d after the initial AI, and all open heifers were resynchronized using the 5 d CO-Synch + CIDR with FTAI at 72 h. Heifers diagnosed pregnant following initial AI received no further treatment. Heifers in the NS treatment were exposed to fertile bulls from d 14 to d 66 following initial AI. Return to estrus data were collected using the Heat Watch Estrus Alert System. Total AI pregnancies tended to be higher (P=0.07) for RS (69.7%) than NS (56.5%) heifers. Overall pregnancy rate was greater for NS (89.4%) than for RS (69.7%) at the end of the breeding season (P < 0.01). The cost of RS was $128.63 and for NS was $82.50 per pregnancy. The expected average calf value per heifer exposed was $195.84 for RS treatment and $357.62 for NS treatment. This difference was attributed to the increased number of open heifers in the RS treatment. The resynchronization of estrus after the initial FTAI yielded a limited number of pregnancies in the breeding season in this study. However, the resynchronization program also cost more per pregnancy. Further investigation into resynchronization should focus on both biological and economic impacts. / Master of Science

The objectives of this study were to determine if fixed-timed artificial insemination (FTAI) at two different times, 0 or 24 h after GnRH administration, in a Presynch-Ovsynch protocol influenced the pregnancy rate (PR) when average and high fertility sires were used. Additionally, a second experiment was conducted to determine the effectiveness of CIDR inserts to allow for resynchronization of estrus in cows that did not conceive or maintain the conceptus at FTAI. Lactating Holstein cows (n = 1,457) from two well-managed dairy herds located in the piedmont region of North Carolina were utilized for 12 mo. First artificial insemination (AI) PR differed for fertility group and was 24.1 and 29.2% for average and high fertility group, respectively. Timing of AI did not influence first AI PR and there was no interaction of fertility group and timing of AI. Cows that received a CIDR insert were detected more frequently in estrus during a 4 d period, d 21 to 24, than control cows, 92.5 and 62.0%, respectively. However, the CIDR insert did not increase the detection of estrus compared to control cows over a normal estrus return interval of 7 d, 18 to 24 d after GnRH administration of a FTAI protocol, 28.8 and 34.2% respectively. In conclusion, the use of high fertility sires is a practical recommendation for improving first AI PR and CIDR inserts allowed more cows to be detected in estrus during a shorter interval, but did not increase the estrus detection rate during a normal estrus return interval. / Master of Science

Fundamento: A estimulação endocárdica convencional do ventrículo direito em ápice ou na região subtricuspídea ocasiona grande alargamento do QRS e importante dessincronização do miocárdio comprometendo a função ventricular. Com o surgimento da estimulação bifocal do VD e com a necessidade de estimulação cardíaca menos deletéria, a estimulação septal do VD tem sido cada vez mais utilizada. Eventualmente têm sido relatados limiares de estimulação mais altos e ondas R menores na estimulação septal. Objetivo: Comparar os parâmetros eletrofisiológicos das estimulações apical e septal, no mesmo paciente, para verificar se existem diferenças que possam interferir na escolha do ponto de estimulação. Este não é um estudo de ressincronização, porém tem o objetivo de contribuir na busca de uma estimulação ventricular monofocal menos deletéria. Casuística e métodos: Estudo prospectivo controlado. Foram incluídos 25 pacientes, com 67,2 ± 9 anos, 10 (40%) mulheres, 15 (60%) homens, com indicações clássicas de marca-passo por bradiarritmias. As etiologias foram Degenerativa em 9 (36%), Insuficiência coronária em 8 (32%), Doença de Chagas em 7 (28%), e Valvopatia em 1 (4%) pacientes. Foram utilizados eletrodos de fixação ativa tanto no ápice e região subtricuspídea, como no septo IVD. Foram medidos e comparados os limiares de comando, impedância e onda R uni e bipolares no momento do implante (medida direta) e após seis meses de evolução (medida por telemetria). Resultados: No implante, as médias dos limiares de comando septais x apicais foram respectivamente 0,73 x 0,74V (unipolar) e 0,73 x 0,78V (bipolar). As médias das ondas R septais x apicais foram 10 x 9,9mV (unipolar) e 12,3 x 12,4mV (bipolar). As médias das impedâncias septais x apicais foram 579 x 621? (unipolar) e 611 x 629? (bipolar). Todas as diferenças entre parâmetros septais e apicais com teste t-pareado bicaudal foram não significativas (p > 0,1). Após seis meses do implante, as médias dos limiares de comando septais x apicais foram respectivamente 0,5 x 0,72V (unipolar) e 0,71 x 0,87V (bipolar). As médias das ondas R septais x apicais foram 11,4 x 9,5mV (unipolar) e 12 x 11,2mV (bipolar). As médias das impedâncias septais x apicais foram 423 x 426? (unipolar) e 578 x 550? (bipolar). As diferenças entre parâmetros septais e apicais após 6 meses com teste t-pareado bicaudal foram não significativas (p > 0,05), exceto quanto às médias dos limiares de estimulação unipolares septal x apical (p=0,02) com menores limiares septais. 27, Conclusão: Este estudo mostrou que não existem diferenças expressivas entre parâmetros eletrofisiológicos de estimulação septal e apical, quando comparadas no mesmo paciente. Estes dados sugerem que em relação aos parâmetros de estimulação não há restrições para a escolha da estimulação septal em ventrículo direito. Este estudo não tem o objetivo de testar a ressincronização ventricular, porém contribui na escolha de uma estimulação monofocal ventricular direita mais fisiológica e menos deletéria. / Background: The conventional endocardial pacing in right ventricular apex or subtricuspid area causes significant QRS enlargement and important left ventricular desynchronization with ventricular function damage. By the introduction of RV bifocal pacing and the need of a less deleterious ventricular stimulation right ventricular septal pacing has been increasingly used. However, despite rare, some authors have reported high pacing thresholds and low R wave in septal pacing. Objective: To compare the electrophysiological parameters of the apical and septal stimulation in the same patient, seeking for any difference that could affect the choice of the pacing point. This is not a resynchronization study however it has the aim to search for for a better monofocal ventricular pacing. Materials and methods: Prospective controlled study of 25 symptomatic patients (67.2 ± 9 years old, 10 [40%] female, 15 [60%] male) having permanent atrial fibrillation with high degree AV block and classical pacemaker indication. The etiologies were 9 (36%) aging, 8 (32%) coronary disease, 7 (28%) Chagas disease and 1 (4%) valvar cardiopathy. There were used active fixation leads both in septal and in apical locations. The generators were Biotronik Philos II DR and Entovis DR. There were measured and compared pacing thresholds, impedance and R wave uni and bipolar during implantation (direct measurement) and after six months of follow-up (telemetry measurement). Results: During implantation, the septal vs apical mean pacing threshold were respectively 0.73 vs 0.74V (unipolar) and 0.73 vs 0.78V (bipolar). Mean R wave septal vs apical were 10 vs 9.9 mV (unipolar) and 12.3 vs 12.4mV (bipolar). The mean impedance septal vs apical were 579 vs 621? (unipolar) and 611vs 629? (bipolar). All septal vs apical comparisons were non-significant (p > 0.1, two-tailed paired t-test). After six months the mean pacing threshold septal vs apical were respectively 0.5 vs 0.72V (unipolar) and 0.71 vs 0.87V (bipolar). The mean R wave septal vs apical were 11.4 vs 9.5mV (unipolar) and 11.2 vs 12mV (bipolar). The mean impedance septal vs apical were 423 vs 426? (unipolar) and 578 vs 550? (bipolar). Only the unipolar septal vs apical mean threshold had significant difference (p = 0.02) with lower septal value. Conclusion: This study showed no significant difference between electrophysiological septal and apical pacing parameters when the 29 comparison is done in the same patient. By this way there are no restrictions for the right ventricular septal pacing. Despite being a non-resynchronization study it may contribute for chosen a less deleterious right ventricular monofocal pacing.

Aims: Non-responder rates for CRT vary from 11 to 46 %. Retrospective data imply a better outcome with stimulation of the latest contracting LV region. Our study analyzed feasibility, safety and clinical outcome of prospectively planned LV lead placement at the site of latest mechanical activation. Methods: Thirty-eight heart failure patients with CRT indication were assessed by 3D TEE and rotation angiography of the coronary sinus. Both images were merged into a single 3D-model to identify CS target veins close to the site of latest mechanical activation. Subsequently LV lead deployment was attempted at the desired target position. Patients were clinically and echocardiographically evaluated at baseline, after 3 and 6 months. Results: The area of latest mechanical activation covered 6 ± 2 segments (38 ± 13 % of LV surface) and was found lateral in 24/37 (65 %), anterior in 11/37 (30 %), inferior in 2/37 (5 %) and septal in 1/37 (3 %) patients. In 36/37 (97 %) patients an appropriate target vein was identified and successful implantation could be performed in 34/37 (92%) patients. Among those patients clinical and echocardiographic response was observed in 91 % and 81 %, respectively. Conclusions: Individualized lead placement at the latest contracting LV site can be performed safely and successfully in the majority of patients. Initial clinical outcome data are encouraging. Identification of target sites requires multimodality integration between LV wall motion data and CS anatomy. Future developments need to improve those technologies and require randomized data on clinical outcome parameters.

Fundamento: A estimulação endocárdica convencional do ventrículo direito em ápice ou na região subtricuspídea ocasiona grande alargamento do QRS e importante dessincronização do miocárdio comprometendo a função ventricular. Com o surgimento da estimulação bifocal do VD e com a necessidade de estimulação cardíaca menos deletéria, a estimulação septal do VD tem sido cada vez mais utilizada. Eventualmente têm sido relatados limiares de estimulação mais altos e ondas R menores na estimulação septal. Objetivo: Comparar os parâmetros eletrofisiológicos das estimulações apical e septal, no mesmo paciente, para verificar se existem diferenças que possam interferir na escolha do ponto de estimulação. Este não é um estudo de ressincronização, porém tem o objetivo de contribuir na busca de uma estimulação ventricular monofocal menos deletéria. Casuística e métodos: Estudo prospectivo controlado. Foram incluídos 25 pacientes, com 67,2 ± 9 anos, 10 (40%) mulheres, 15 (60%) homens, com indicações clássicas de marca-passo por bradiarritmias. As etiologias foram Degenerativa em 9 (36%), Insuficiência coronária em 8 (32%), Doença de Chagas em 7 (28%), e Valvopatia em 1 (4%) pacientes. Foram utilizados eletrodos de fixação ativa tanto no ápice e região subtricuspídea, como no septo IVD. Foram medidos e comparados os limiares de comando, impedância e onda R uni e bipolares no momento do implante (medida direta) e após seis meses de evolução (medida por telemetria). Resultados: No implante, as médias dos limiares de comando septais x apicais foram respectivamente 0,73 x 0,74V (unipolar) e 0,73 x 0,78V (bipolar). As médias das ondas R septais x apicais foram 10 x 9,9mV (unipolar) e 12,3 x 12,4mV (bipolar). As médias das impedâncias septais x apicais foram 579 x 621? (unipolar) e 611 x 629? (bipolar). Todas as diferenças entre parâmetros septais e apicais com teste t-pareado bicaudal foram não significativas (p > 0,1). Após seis meses do implante, as médias dos limiares de comando septais x apicais foram respectivamente 0,5 x 0,72V (unipolar) e 0,71 x 0,87V (bipolar). As médias das ondas R septais x apicais foram 11,4 x 9,5mV (unipolar) e 12 x 11,2mV (bipolar). As médias das impedâncias septais x apicais foram 423 x 426? (unipolar) e 578 x 550? (bipolar). As diferenças entre parâmetros septais e apicais após 6 meses com teste t-pareado bicaudal foram não significativas (p > 0,05), exceto quanto às médias dos limiares de estimulação unipolares septal x apical (p=0,02) com menores limiares septais. 27, Conclusão: Este estudo mostrou que não existem diferenças expressivas entre parâmetros eletrofisiológicos de estimulação septal e apical, quando comparadas no mesmo paciente. Estes dados sugerem que em relação aos parâmetros de estimulação não há restrições para a escolha da estimulação septal em ventrículo direito. Este estudo não tem o objetivo de testar a ressincronização ventricular, porém contribui na escolha de uma estimulação monofocal ventricular direita mais fisiológica e menos deletéria. / Background: The conventional endocardial pacing in right ventricular apex or subtricuspid area causes significant QRS enlargement and important left ventricular desynchronization with ventricular function damage. By the introduction of RV bifocal pacing and the need of a less deleterious ventricular stimulation right ventricular septal pacing has been increasingly used. However, despite rare, some authors have reported high pacing thresholds and low R wave in septal pacing. Objective: To compare the electrophysiological parameters of the apical and septal stimulation in the same patient, seeking for any difference that could affect the choice of the pacing point. This is not a resynchronization study however it has the aim to search for for a better monofocal ventricular pacing. Materials and methods: Prospective controlled study of 25 symptomatic patients (67.2 ± 9 years old, 10 [40%] female, 15 [60%] male) having permanent atrial fibrillation with high degree AV block and classical pacemaker indication. The etiologies were 9 (36%) aging, 8 (32%) coronary disease, 7 (28%) Chagas disease and 1 (4%) valvar cardiopathy. There were used active fixation leads both in septal and in apical locations. The generators were Biotronik Philos II DR and Entovis DR. There were measured and compared pacing thresholds, impedance and R wave uni and bipolar during implantation (direct measurement) and after six months of follow-up (telemetry measurement). Results: During implantation, the septal vs apical mean pacing threshold were respectively 0.73 vs 0.74V (unipolar) and 0.73 vs 0.78V (bipolar). Mean R wave septal vs apical were 10 vs 9.9 mV (unipolar) and 12.3 vs 12.4mV (bipolar). The mean impedance septal vs apical were 579 vs 621? (unipolar) and 611vs 629? (bipolar). All septal vs apical comparisons were non-significant (p > 0.1, two-tailed paired t-test). After six months the mean pacing threshold septal vs apical were respectively 0.5 vs 0.72V (unipolar) and 0.71 vs 0.87V (bipolar). The mean R wave septal vs apical were 11.4 vs 9.5mV (unipolar) and 11.2 vs 12mV (bipolar). The mean impedance septal vs apical were 423 vs 426? (unipolar) and 578 vs 550? (bipolar). Only the unipolar septal vs apical mean threshold had significant difference (p = 0.02) with lower septal value. Conclusion: This study showed no significant difference between electrophysiological septal and apical pacing parameters when the 29 comparison is done in the same patient. By this way there are no restrictions for the right ventricular septal pacing. Despite being a non-resynchronization study it may contribute for chosen a less deleterious right ventricular monofocal pacing.

Indiana University-Purdue University Indianapolis (IUPUI) / Metaphors are used to conceptualize one thing in terms of another that is more familiar or concrete. The use of metaphors in patient-provider communication has helped providers generate empathy and explain concepts effectively, improving patient satisfaction and understanding of health-related concepts. With advances in technology, concepts related to health monitoring have become increasingly complex, making the potential for using metaphors in health communication at its highest relevancy. With the increase in health data there is a need to improve tools to help people understand complex information. Ethical considerations, such as possible misinterpretation of health data, as well as the potential to widen disparities because of factors such as health literacy, must be addressed. Metaphors are powerful tools that can make explanation of information accessible, accurate, and effective for people who are monitoring their data. The current research aims to contribute design recommendations for using metaphors in communication between clinicians and patients for monitoring biventricular (BiV) pacing, a complex device data element used in the monitoring of patients with heart failure (HF) who have cardiac resynchronization therapy (CRT) devices. The overarching goal is to understand this process such that it can be applied to broader communication needs in health informatics. The study addresses the following aims: Aim 1: Identify metaphors clinicians use to conceptualize BiV pacing for CRT devices using semi-structured interviews with clinician experts. Aim 2: Identify metaphors that help patients conceptualize BiV pacing for CRT devices using semi-structured interviews with patients, and exploring the metaphors identified in Aim 1. Aim 3: Develop design recommendations for health informatics interventions using an understanding of metaphors that help patients understand BiV pacing for CRT devices. Themes from analysis of Aims 1 and 2 contribute to recommendations for the use of metaphors in health informatics interventions. The purpose of this work is to contribute to an in-depth understanding of metaphors in a specific health informatics context. Importantly, this research applies methods and principles from the field of health communication to address a communication-related issue in health informatics. / 2022-12-28

No description available.

No description available.

Two trials were conducted to compare the effectiveness of fixed-time artificial insemination (AI) to AI based upon visual detection of estrus following superstimulation of donor beef cows. In Trial 1, multiparous beef cows (n = 31) were randomly allotted to one of three treatments following superstimulation and removal of an intravaginal progesterone insert (CIDR). Cows in the Control group were inseminated at 12 and 24 h after onset of estrus. Cows in the Estradiol group were injected with estradiol-17β (1 mg, im) at 12 h and inseminated at 24 and 36 h after CIDR removal. Cows in the pLH36 group were injected with porcine LH (Lutropin, 12.5 mg, im) at 24 h and inseminated at 36 and 48 h after CIDR removal. Mean numbers of viable embryos were 7.8, 3.6 and 9.6 for Control, Estradiol and pLH36 treatment groups, respectively (P > 0.10). In Trial 2, multiparous beef cows (n = 22) were randomly allotted to one of three treatments following superstimulation and removal of a CIDR. Sixteen of the cows were superstimulated a second time approximately 50 days later and allotted to one of the two treatments that differed from the initial treatment group. Cows in the Control group were inseminated at 12 and 24 h after onset of estrus. Cows in the two pLH groups were injected with porcine LH (Lutropin,12.5 mg, im) at 24 h after CIDR removal and were inseminated with either one unit of semen at 36 and 48 h (pLH36) or with two units of semen at 48 h (pLH48) after CIDR removal. Mean numbers of viable embryos were 3.0, 6.4 and 3.8 for Control, pLH36 and pLH48 treatment groups, respectively (P > 0.10). These data indicate that administration of pLH can facilitate use of fixed-time AI in superovulated beef cows without sacrificing embryo production. The second study evaluated the efficacy of resynchronizing beef cow recipients using CIDR devices for only 7 or 14 d. Recipient cows received CIDRs either on the day of transfer (n = 88) or 7 d post-transfer (n = 230). All CIDRs were removed on d 21 and cows were observed for estrus between d 22 and 24. Cows that displayed estrus were ultrasounded on d 30, those cows not pregnant that possessed a CL had an embryo transferred that day. Cows were later examined for pregnancies approximately 23 to 30 d later. There were no differences in pregnancy rates between cows with 7 or 14 d CIDRs and therefore data were combined. Pregnancy rates at two different ranches indicate that beef cow recipients can be successfully resynchronized by insertion of a CIDR without compromising pregnancy rates of transferred embryos. At Center Ranch the pregnancy rate for the first transfer was 57% while the resynchronized group that received the second transfer had a pregnancy rate of 55%. At Mound Creek Ranch the first transfer of embryos produced 59% pregnancy rates while the second transfer had a pregnancy rate of 71%. No significant differences (P > 0.05) were observed between the pregnancy rates of the initial transfer and those of the resynchronized transfer using only CIDRs, indicating that resynchronization using CIDRs can be used without reducing pregnancy rates.

The general purpose of this thesis was to investigate new cardiac resynchronization therapy (CRT) optimization techniques and to assess their reliability when compared to invasive measurements of left ventricular contractility (LV dP/dtmax).We first assessed whether cardiac output (CO) measured by trans-thoracic impedance cardiography could correctly identify the optimal interventricular (VV) pacing interval while using invasive measurements of LV dP/dtmax as reference. We did not find any significant statistical correlation between the two optimizing methods when their corresponding optimal VV intervals were compared. We also tested the hypothesis that measurements of right ventricular contractility (RV dP/dtmax) could be used to guide VV delay optimization in CRT. The comparison of optimal VV intervals obtained from the left and right ventricular dP/dtmax did not show a statistically significant correlation; however, a positive correlation was found when broader VV intervals were evaluated and we concluded that this finding deserves further investigation. An interesting alternative for CRT optimization is the use of device integrated algorithms or sensors capable to adapt the CRT settings to the current needs of the individual patient. In this respect we investigated the use of cardiogenic impedance (CI) measurements obtained through the CRT-D device as a method for CRT optimization with invasive measurements of LV dP/dtmax as a reference. Our results showed that CI could be measured through the device after implantation and that a patient-specific impedance-based prediction model was capable to accurately predict the optimal AV and VV delays. To follow up on these positive results we re-evaluated the patient-specific impedance-based prediction models 24 hours post implantation and investigated the possibility of calibrating them using parameters derived from non-invasive measurements of arterial pressure obtained by finger pelthysmography at implantation.The results showed that the patient-specific impedance-based prediction models did not perform as well on the follow-up data as they did on the data from implantation day and that they correlated poorly with plethysmographic parameters. Our studies suggest that novel methods for CRT optimization should be thoroughly evaluated and compared to established measures of left ventricular function prior to introduction into clinical practice.