Doppler Mitral Inflow Variables Time Course After Treadmill Stress Echo with and Without Ischemic Response

This study evaluated Doppler mitral inflow variables changes from rest to post-exercise among 104 subjects with and without echocardiographic evidence of ischemic response (IR) to exercise (63.9 ± 11 years, 54% male, 32% with IR) who underwent a clinically indicated treadmill stress echo (TSE) test. The time from exercise cessation to imaging (TIME) was recorded. The changes (after TSE minus baseline values) in the peak E-wave velocity (∆E) [34.2 vs. 24.2, p = 0.024] and E-wave deceleration rate (∆DR) [348.0 vs. 225.7, p = 0.010] were bigger in ischemic than in nonischemic subjects, while the changes in the peak A-wave velocity (∆A) did not differ [7.9 vs. 15.0, p = 0.082]. The correlations between Doppler variables and IR, TIME, and TIME*IR interaction were analyzed. We observed a significant interaction between TIME and IR regarding ∆E and ∆DR. The differences in the regression line slopes of time courses for ∆E and ∆DR based on IR were significant: ∆E (–0.09 vs. –8.17, p = 0.037) and ∆DR (11.23 vs. –82.60, p = 0.022). Main findings: 1. Time courses after exercise of ∆E and ∆DR in subjects with and without IR were different. 2. ∆E and ∆DR did not differ between subjects with and without IR at exercise cessation (TIME = 0). 3. The simple main effect of ischemia on ∆E and ∆DR was significant at TIME of ≥3 min. Divergent time courses of ∆E and ∆DR after exercise might be promising for detecting diastolic dysfunction caused by ischemia.

Effect of renin-angiotensin system blocker on COVID-19 in young patients with hypertension

Hypertension is found frequently in patients with COVID-19 and is often treated with ACE inhibitors (ACEIs) and angiotensin receptor blockers (ARBs). SARS-CoV-2, the pathogen of COVID-19, binds to the receptors of ACE2 to enter the alveolar cells, raising questions on whether these drugs are salutary or harmful with respect to any propensity for COVID-19 or to disease prognosis. We investigated the impact of ACEI/ARB and the clinical prognosis of patients with hypertension with COVID-19. In this study, 250 patients with hypertension (<45 years old) with COVID-19 were recruited. None of these patients had any chronic disease except for hypertension. The study population was grouped according to antihypertensive medication: ACEI/ARB user and non-ACEI/ARB user. Patients were followed for clinical prognosis and biochemical and radiological findings during their hospital stay. Adverse cardiovascular event (myocardial infarction, all-cause death, stroke), transfer to the intensive care unit, severity of symptoms during the treatment course, length of hospital stay and effort capacity in the treadmill stress test were recorded. During hospital stay, there was no significant difference in terms of length of hospital stay, medication for COVID-19, left ventricular ejection fraction on echocardiography and metabolic equivalents in the treadmill stress test between patients treated with and without ACEI/ARB. During treatment of COVID-19, there was no significant difference in clinical adverse event, effort capacity and clinical course between patients with and without ACEI/ARB. It appears that patients with COVID-19 may continue to use ACEI/ARB or that ACEI/ARB may be added safely to their antihypertensive treatment.

The Ordering of Medical Things: Medical Practices and Complexity

<p>This project is an investigation into medicine in action. The aim is to understand how medical interactions generate order via the diagnosis of disease; how the patient, the body, and illness are made intelligible, and how particular courses of action are decided upon as a result. Using video and audio data supplied by the Applied Research on Communication in Health (ARCH) research team, this project follows Simon, a middle aged, Caucasian male with chest pain, as he participates in consultations with his GP and cardiologist, and as he undergoes a cardio treadmill-stress test. This project argues for adopting an Actor-Network theory (ANT) based approach to studying interactions. Unlike more traditional sociology approaches, this project considers the role of non-human objects in interaction. Non-human objects are often key actors in the interactions that provide the world with a sense of order. I will provide an epistemological justification for ANT's key premises and outline the method that these premises entail. Following three interactions, this project illustrates that the principal actors involved in producing intelligibility varies. In the GP consultation, the GP and Simon were principal actors in rendering chest pain intelligible. In the treadmill stress test, the material instrumentation, carefully aligned with the Simon's body by the cardiologist, was vital to ensuring a particular account of the heart was produced. Simon was little more than a compliant body in this interaction. In the final interaction, the cardiologist was the principal actor in making sense of these accounts of chest pain and the potentially conflicting picture of the "healthy" heart. The cardiologist suggests that the account of the heart produced by the treadmill-stress test may be flawed, and encourages Simon to self-monitor and self-regulate. I will argue that the uncertainty generated by conflicting accounts is common to medical practices. Medical professionals respond to this by encouraging individuals to monitor and reduce risk. By adopting the ANT approach, I found that the patient and his body are sometimes intelligible as somatic entities, sometimes as an expressive, accounting agent, and sometimes as a self-responsible individual. These various renditions hold together as a being a single individual "Simon".</p>

The Ordering of Medical Things: Medical Practices and Complexity

<p>This project is an investigation into medicine in action. The aim is to understand how medical interactions generate order via the diagnosis of disease; how the patient, the body, and illness are made intelligible, and how particular courses of action are decided upon as a result. Using video and audio data supplied by the Applied Research on Communication in Health (ARCH) research team, this project follows Simon, a middle aged, Caucasian male with chest pain, as he participates in consultations with his GP and cardiologist, and as he undergoes a cardio treadmill-stress test. This project argues for adopting an Actor-Network theory (ANT) based approach to studying interactions. Unlike more traditional sociology approaches, this project considers the role of non-human objects in interaction. Non-human objects are often key actors in the interactions that provide the world with a sense of order. I will provide an epistemological justification for ANT's key premises and outline the method that these premises entail. Following three interactions, this project illustrates that the principal actors involved in producing intelligibility varies. In the GP consultation, the GP and Simon were principal actors in rendering chest pain intelligible. In the treadmill stress test, the material instrumentation, carefully aligned with the Simon's body by the cardiologist, was vital to ensuring a particular account of the heart was produced. Simon was little more than a compliant body in this interaction. In the final interaction, the cardiologist was the principal actor in making sense of these accounts of chest pain and the potentially conflicting picture of the "healthy" heart. The cardiologist suggests that the account of the heart produced by the treadmill-stress test may be flawed, and encourages Simon to self-monitor and self-regulate. I will argue that the uncertainty generated by conflicting accounts is common to medical practices. Medical professionals respond to this by encouraging individuals to monitor and reduce risk. By adopting the ANT approach, I found that the patient and his body are sometimes intelligible as somatic entities, sometimes as an expressive, accounting agent, and sometimes as a self-responsible individual. These various renditions hold together as a being a single individual "Simon".</p>

Arterial Doppler Waveforms Are Independently Associated With Maximal Walking Distance in Suspected Peripheral Artery Disease Patients

Objective: Arterial Doppler waveform recordings are commonly used to assess lower extremity arterial disease (LEAD) severity. However, little is known about the relationship between arterial Doppler waveform profiles and patients' walking capacity. The purpose of this study was to assess whether arterial Doppler waveforms are independently associated with maximal walking distance (MWD) in patients experiencing exertional limb symptoms.Materials and Methods: This cross-sectional study included suspected LEAD patients experiencing exertional limb symptoms. In both lower extremities, arterial Doppler waveforms and ankle-brachial index (ABI) values were obtained from the pedis and tibial posterior arteries. Each arterial flow measurement was ranked using the Saint-Bonnet classification system. Treadmill stress testing (3.2 km/h, 10% slope) coupled with exercise oximetry (Exercise-TcPO2) were used to determine MWD. Delta from rest oxygen pressure (DROP) was calculated. Following treadmill stress testing, post-exercise ABI values were recorded. Univariate and multivariate analyses were used to determine the clinical variables associated with MWD.Results: 186 patients experiencing exertional limb symptoms (62 ± 12 years and 26.8 ± 4.5 kg/m2) were included between May 2016 and June 2019. Median [25th; 75th] treadmill MWD was 235 [125;500]m. Better arterial Doppler waveforms were associated with better walking distance (p = 0.0012). Whereas, median MWD was 524 [185;525]m in the group that yielded the best Doppler waveforms, it was 182 [125,305]m in the group with the poorest Doppler waveforms (p = 0.0012). MWD was significantly better (p = 0.006) in the patients with the best ABIs. However, arterial Doppler waveforms alone were significantly associated with MWD (p = 0.0009) in the multivariate model. When exercise variables (post-exercise ABI or DROP) were incorporated into the multivariate model, these were the only variables to be associated with MWD.Conclusion: Of the various clinical parameters at rest, Doppler flow waveform profiles were associated with MWD in suspected LEAD patients. A stronger link was however found between exercise variables and MWD.

COMPARATIVE STUDY OF TREADMILL STRESS TEST(TMT) WITH INVASIVE CORONARY ANGIOGRAPHY (CAG) IN PATIENTS WITH SUSPECTED CORONARY ARTERY DISEASE

Background- There are few studies which compared invasive coronary angiography (CAG) in patients presenting with chest pain (atypical, probably ischemic) in outpatient department with negative or inconclusive treadmill stress test (TMT). Objective- To assess CAG findings in patient with suspected iscemic chest pain, with negative or inconclusive TMT. Methods- Patients with chest pain (atypical, probably ischemic) underwent TMT and classified as TMT negative or inconclusive. These patients underwent CAG and findings were analysed. Results - 50 patients completed the study protocol. Of these 50 patients who underwent TMT, 31 (62%) were TMT negative and 19 (38%) were TMT inconclusive. In TMT negative group CAG showed obstructive lesion in 6(19.4%), and non obstructive lesion in 25(80.6%). In TMT inconclusive group CAG showed obstructive lesion in 11(57.8%), while non obstructive lesion in 8(42.2%). Conclusion-In patients with atypical chest pain with negative or inconclusive TMT with suspicion of coronary ischemia CAG provides an important diagnostic tool for assessing, especially with TMT inconclusive group.