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Continuous Thermodilution is a novel method of quantifying coronary flow (Q) in mL/min. To account for variability of Q within the cardiac cycle, the trace is smoothened with a 2 s moving average filter. This can sometimes be ineffective due to significant heart rate variability, ventricular extrasystoles, and deep inspiration, resulting in a fluctuating temperature trace and ambiguity in the location of the “steady state”. This study aims to assess whether a longer moving average filter would smoothen any fluctuations within the continuous thermodilution traces resulting in improved interpretability and reproducibility on a test–retest basis. Patients with ANOCA underwent repeat continuous thermodilution measurements. Analysis of traces were performed at averages of 10, 15, and 20 s to determine the maximum acceptable average. The maximum acceptable average was subsequently applied as a moving average filter and the traces were re-analysed to assess the practical consequences of a longer moving average. Reproducibility was then assessed and compared to a 2 s moving average. Of the averages tested, only 10 s met the criteria for acceptance. When the data was reanalysed with a 10 s moving average filter, there was no significant improvement in reproducibility, however, it resulted in a 12% diagnostic mismatch. Applying a longer moving average filter to continuous thermodilution data does not improve reproducibility. Furthermore, it results in a loss of fidelity on the traces, and a 12% diagnostic mismatch. Overall, current practice should be maintained.

ObjectiveDiastolic-systolic velocity ratio (DSVR) is a resting index to assess stenoses in the left anterior descending artery (LAD). DSVR can be measured by echocardiographic or intracoronary Doppler flow velocity. The objective of this cohort study was to elucidate the fundamental rationale underlying the decreased DSVR in coronary stenoses.MethodsIn cohort 1, simultaneous measurements of intracoronary Doppler flow velocity and pressure were acquired in the LAD of 228 stable patients. Phasic stenosis resistance, microvascular resistance and total vascular resistance (defined as stenosis and microvascular resistance combined) were studied during physiological resting conditions. Stenoses were classified according to severity by strata of 0.10 fractional flow reserve (FFR) units.ResultsDSVR was decreased in stenoses with lower FFR. Stenosis resistance was equal in systole and diastole for every FFR stratum. Microvascular resistance was consistently higher during systole than diastole. In lower FFR strata, stenosis resistance as a percentage of the total vascular resistance increases both during systole and diastole. The difference between the stenosis resistance as a percentage of total vascular resistance during systole and diastole increases for lower FFR strata, with an accompanying rise in diastolic-systolic resistance ratio. A significant inverse correlation was observed between DSVR and the diastolic-systolic resistance ratio (r=0.91, p<0.001). In cohort 2 (n=23), DSVR was measured both invasively and non-invasively by transthoracic echocardiography, yielding a good correlation (r=0.82, p<0.001).ConclusionsThe rationale by which DSVR is decreased distal to coronary stenoses is dependent on a comparatively higher influence of the increased stenosis resistance on total vascular resistance during diastole than systole.

Intracoronary continuous thermodilution has been recently proposed as an invasive method to quantify absolute coronary flow (Qabs) and resistance (Rabs) in vivo. The aim of the present study is to develop and validate of a novel pressure-wire- and microcatheter-free surrogate of coronary flow and resistance derived from a standard coronary angiogram. Angiography derived coronary flow (Qangio) and resistance (Rangio) was prospectively validated in a two-center cohort of patients from Oxford Heart Centre and the Essex Cardiothoracic Centre. Qabs and Rabs were measured during resting and hyperemic conditions with continuous thermodilution using the Rayflow microcatheter. Qangio and Rangio were computed from the diagnostic coronary angiogram in a blinded fashion in resting and hyperemic conditions. A total of 62 patients and 115 vessels were included in the present analysis. The median Qabs at rest was 75 ml/min (53–95) and 151 ml/min (105–203) during hyperemia; Qangio at rest was 84 ml/min (66–108) and 154 ml/min (115–195) during hyperemia. There was a strong correlation between Qabs and Qangio (R = 0,72; p < 0.001, R = 0,86; p < 0.001 respectively) with satisfactory interclass correlation (0.841, 95% CI 0.509–0.957; p = 0.0003). The median Rabs was 1111 mmHg/(L/min) (830-1581.4) at rest and 454 mmHg/(L/min) (348–610) during hyperemia; angiographic resistance (Rangio) was 937.4 mmHg/(L/min) (695.4–1261.9) at rest and 492.4 mmHg/(L/min) (406–697) during hyperemia. There was a strong correlation between Rabs and Rangio in both conditions (R = 0,81; p < 0.001 and R = 0,78; p < 0.001 respectively). The was a good correlation between absolute coronary flow reserve (CFR) and angiography-derived CFR (R = 0,61; p < 0.001) and between absolute microvascular resistance reserve (MRR) and angiography-derived MRR (R = 0,49; p < 0.001).Condensed abstractWe developed and validated a novel non-invasive, fully angiographic, pressure-wire- and microcatheter-free method to quantify coronary flow and resistance in resting and hyperemic conditions. Angiography-derived coronary flow and resistance was prospectively validated in a two-center cohort of 62 patients and 115 vessels against absolute coronary flow and resistance measured with Rayflow microcatheter. We found a strong correlation between angiography-derived flow and resistance and absolute coronary flow and resistance, with satisfactory interclass correlation. There was a good correlation between absolute coronary flow reserve (CFR) and angiography-derived CFR and between absolute microvascular resistance reserve (MRR) and angiography-derived MRR.

Background: To assess whether hydrostatic pressure gradients caused by coronary height differences in supine versus prone positioning during invasive physiological stenosis assessment affect resting and hyperaemic pressure-based indices or coronary flow. Methods: Twenty-three coronary stenoses were assessed in twenty-one patients with stable coronary artery disease. All patients had a stenosis of at least 50% visually defined on previous coronary angiography. Pd/Pa, iFR, FFR, and coronary flow velocity (APV) measured using a Doppler were recorded across the same stenosis, with the patient in the prone position, followed by repeat measurements in the standard supine position. Results: When comparing prone to supine measurements in the same stenosis, in the LAD, there was a significant change in mean Pd/Pa of 0.08 ± 0.04 (p = 0.0006), in the iFR of 0.06 ± 0.07 (p = 0.02), and in the FFR of 0.09 ± 0.07 (p = 0.003). In the Cx, there was a change in mean Pd/Pa of 0.05 ± 0.04 (p = 0.009), iFR of 0.07 ± 0.04 (p = 0.01), and FFR of 0.05 ± 0.03 (p = 0.006). In the RCA, there was a change in Pd/Pa of 0.05 ± 0.04 (p = 0.032), iFR of 0.04 ± 0.05 (p = 0.19), and FFR of 0.04+−0.03 (p = 0.004). Resting and hyperaemic coronary flow did not change significantly (resting delta APV = 1.6 cm/s, p = 0.31; hyperaemic delta APV = 0.9 cm/s, p = 0.85). Finally, 36% of iFR measurements and 26% of FFR measurements were re-classified across an ischaemic threshold when prone and supine measurements were compared across the same stenosis. Conclusions: Pd/Pa, iFR, and FFR were affected by hydrostatic pressure variations caused by coronary height differences in prone versus supine positioning. Coronary flow did not change signifying a purely pressure-based phenomenon.

The Vd(m) (a measure of DMF) was compared to that obtained in healthy volunteers (mean age 35, 63% male) and also to other indexed CMR parameters, including left atrial area and echocardiographic parameters of diastolic function (tissue doppler and strain imaging).

Interdisciplinary teams with common planning time have been a hallmark of the middle school organizational structure since the 1960s, yet research on the effective use of common planning time is limited. This study explores how interdisciplinary teams at schools designated Kentucky Schools to Watch use common planning time, including the factors that enhance common planning time effectiveness, the beliefs and perceptions of the teachers concerning the use of common planning time, and the topics and activities discussed during common planning time sessions. Results indicate a common vision and mission, clearly defined goals for all types of planning (interdisciplinary team planning, grade level planning, and professional learning communities), and effective building leadership are factors for enhancing the effectiveness of common planning time.

High-performing middle schools are a critical link in the educational continuum. In an effort to stimulate the sluggish reform efforts of middle schools, the National Forum to Accelerate Middle-Grades Reform established the Schools to Watch recognition program. Using responses of school personnel to a statewide survey, this study examined the perceived level of implementation of key tenets of the middle school concept as outlined by This We Believe: Successful Schools for Young Adolescents (National Middle School Association, 2003) in schools designated Kentucky Schools to Watch as compared to non-designated schools. Additionally, the study reviewed the academic performance of Kentucky's middle schools on the Kentucky Core Content Test to determine whether the schools identified as Kentucky Schools to Watch experienced higher levels of student academic achievement. Results indicated a slightly higher perceived level of implementation of key tenets of the middle school concept in Kentucky's Schools to Watch and revealed overall higher levels of academic achievement as measured by the Kentucky Core Content Test.

Fractional flow reserve (FFR) uses pressure-based measurements to assess the severity of a coronary stenosis. Distal pressure (Pd) is often at a different vertical height to that of the proximal aortic pressure (Pa). The difference in pressure between Pd and Pa due to hydrostatic pressure, may impact FFR calculation. One hundred computed tomography coronary angiographies were used to measure height differences between the coronary ostia and points in the coronary tree. Mean heights were used to calculate the hydrostatic pressure effect in each artery, using a correction factor of 0.8 mmHg/cm. This was tested in a simulation of intermediate coronary stenosis to give the \"corrected FFR\" (cFFR) and percentage of values, which crossed a threshold of 0.8. The mean height from coronary ostium to distal left anterior descending (LAD) was +5.26 cm, distal circumflex (Cx) -3.35 cm, distal right coronary artery-posterior left ventricular artery (RCA-PLV) -5.74 cm and distal RCA-posterior descending artery (PDA) +1.83 cm. For LAD, correction resulted in a mean change in FFR of +0.042, -0.027 in the Cx, -0.046 in the PLV and +0.015 in the PDA. Using 200 random FFR values between 0.75 and 0.85, the resulting cFFR crossed the clinical treatment threshold of 0.8 in 43% of LAD, 27% of Cx, 47% of PLV and 15% of PDA cases. There are significant vertical height differences between the distal artery (Pd) and its point of normalization (Pa). This is likely to have a modest effect on FFR, and correcting for this results in a proportion of values crossing treatment thresholds. Operators should be mindful of this phenomenon when interpreting FFR values.

This study explored the practices, strategies, and approaches of three middle grades teachers experienced at implementing the functions of advisory in to the everyday classroom through a case study approach. In addition, the study determined how students responded to these practices and how climate and demographic factors influenced the implementation of different activities. Multiple sources of data, including classroom observations, teacher interviews, student interviews, and archival data were used to describe the experiences of the three teachers. Analysis of the data yielded the following findings: (a) The different functions of advisory were ultimately infused through four main components of teaching: (1) relationships, (2) teaching strategies and activities, (3) classroom resources, and (4) classroom democracy. (b) Developing positive relationships with students through engaging in personal conversation, taking time to learn about individual students, being willing to share personal information with students, and emphasizing that they are always willing to help students allowed the teachers to infuse the functions of promoting a safe, nurturing classroom environment, facilitating positive interaction between students and teachers, establishing a learning community that emphasizes communication, and helping provide an adult advocate for every child. (c) Specific teaching strategies and activities that helped incorporate numerous functions were team-building activities, group discussions and Paideia seminars, group projects and presentations, current events activities, poetry recitations, role-playing, and journal writing. These activities related to the following functions: develop self-awareness, self respect, and self discipline, establish a learning community that emphasizes communication, engage students in moral development opportunities, foster interpersonal competence, and help students develop pertinent life skills such as critical thinking, problem-solving, and decision making. (d) Demographic considerations such as issues of race and gender had little impact on the implementation of the different functions. Issues of climate had a greater influence on the implementation of the different functions of advisory. (e) Key issues of climate were individual teacher motivation, student-to-student relationships, teacher-to-student relationships, student grouping, and classroom behavior. This study concluded that teachers are able to incorporate the different functions of middle school advisory into the everyday classroom through both intentional and unintentional manners. Teachers were able to incorporate, at one point or another, all eight of the functions of middle school advisory.

[...] they give students the responsibility to prepare, organize, and direct the conference with their parents, emphasizing the academic and behavioral accomplishments they have achieved during the school year and targeting additional goals and areas for growth. The primary focus of the student-led conferences is on academic progress, not failure or misbehavior, which is often the case at traditional parent-teacher conferences. Because the most important player-the student-is present, students and parents can address concerns directly and seek the intervention of the classroom teacher, if necessary.