Poor Exercise Tolerance Research Articles

Cyanosis in a Previously Well Child.

Cyanosis in a Previously Well Child.

Ultrasound assessment of the rectus femoris in patients with chronic obstructive pulmonary disease predicts poor exercise tolerance: an exploratory study

BackgroundReduced exercise tolerance is an important clinical feature of chronic obstructive pulmonary disease (COPD) and is associated with poor prognosis. The 6-min walk test (6MWT) is widely used to assess exercise capacity; however, it is not commonly administered in primary medical institutions because it requires a suitable site and professional training. Ultrasound has great potential for evaluating skeletal muscle dimensions in COPD. However, whether skeletal muscle ultrasound can predict impaired exercise tolerance is unclear.MethodsThe study included 154 stable patients with COPD, who were randomly divided into a development set and a validation set. The thickness (RFthick) and cross-sectional area (RFcsa) of the rectus femoris were measured using ultrasound. Standardized RFthick (STD- RFthick) and Standardized RFcsa (STD-RFcsa) were obtained via standardization of RFthick and RFcsa by patients' height.ResultsStrong correlations were observed between the 6MWD and RFthick (r = 0.84, p < 0.001) and between the 6MWD and RFcsa (r = 0.81, p < 0.001). In the development set, the optimal cut-off values for men and women for predicting poor exercise tolerance were < 3.098 cm/m and < 3.319 cm/m for STD-RFthick and < 4.052 cm2/m and < 4.366 cm2/m for STD-RFcsa, respectively. In the validation set, the area under the curve (AUC) values for the prediction of a 6MWD < 350 by STD-RFthick and STD-RFcsa were 0.881 and 0.903, respectively. Finally, the predictive efficacy of STD-RFthick (AUC: 0.922), STD-RFcsa (AUC: 0.904), and the derived nomogram model (AUC: 0.98) for exercise tolerance was superior to that of the sit-to-stand test and traditional clinical features.ConclusionsRectus femoris ultrasound has potential clinical application to predict impaired exercise tolerance in patients with COPD.

The effects of pulmonary hypertension on skeletal muscle oxygen pressures in contracting rat spinotrapezius muscle.

What is the central question of this study? Does impairment in the dynamics of O2 transport in skeletal muscle during a series of contractions constitute a potential mechanism underlying reduced exercise capacity in pulmonary hypertension? What is the main finding and its importance? Pulmonary hypertension compromises the dynamic matching of skeletal muscle O2 delivery-to-utilization following contraction onset in the rat spinotrapezius muscle. These results implicate a role for vascular dysfunction in the slow kinetics and exercise intolerance present in pulmonary hypertension. Pulmonary hypertension (PH) is characterized by pulmonary vascular dysfunction and exercise intolerance due, in part, to compromised pulmonary and cardiac function. We tested the hypothesis that there are peripheral (i.e., skeletal muscle) aberrations in O2 delivery ( )-to-O2 utilization ( ) matching and vascular control that might help to explain poor exercise tolerance in PH. Furthermore, we investigated the peripheral effects of nitric oxide (NO) in attenuating these decrements. Male Sprague-Dawley rats (n=21) were administered monocrotaline (MCT; 50mg/kg, i.p.) to induce PH. Disease progression was monitored via echocardiography. Phosphorescence quenching determined the O2 partial pressure in the interstitial space ( ) in the spinotrapezius muscle at rest and during contractions under control (SNP-) and NO-donor (sodium nitroprusside, SNP+) conditions. MCT rats displayed right ventricular (RV) hypertrophy (right ventricle/(left ventricle + septum): 0.44 (0.13) vs. 0.28 (0.05)), pulmonary congestion, increased RV systolic pressure (48 (18) vs. 20 (8) mmHg) and arterial hypoxaemia ( : 64 (9) vs. 82 (9) mmHg) compared to healthy controls (HC) (P<0.05). was significantly lower in MCT rats during the first 30s of SNP- contractions. SNP superfusion elevated in both groups; however, MCT rats demonstrated a lower throughout SNP+ contractions versus HC (P<0.05). Thus, for small muscle mass exercise in MCT rats, muscle oxygenation is impaired across the rest-to-contractions transition and exogenous NO does not raise the -to- ratio in contracting muscle to the same levels as HC. These data support muscle -to- mismatch as a potential contributor to slow kinetics and therefore exercise intolerance in PH and suggest peripheral vascular dysfunction or remodelling as a possible mechanism.

Exertional ventilation/carbon dioxide output relationship in COPD: from physiological mechanisms to clinical applications.

There is well established evidence that the minute ventilation (V'E)/carbon dioxide output (V'CO2 ) relationship is relevant to a number of patient-related outcomes in COPD. In most circumstances, an increased V'E/V'CO2 reflects an enlarged physiological dead space ("wasted" ventilation), although alveolar hyperventilation (largely due to increased chemosensitivity) may play an adjunct role, particularly in patients with coexistent cardiovascular disease. The V'E/V'CO2 nadir, in particular, has been found to be an important predictor of dyspnoea and poor exercise tolerance, even in patients with largely preserved forced expiratory volume in 1 s. As the disease progresses, a high nadir might help to unravel the cause of disproportionate breathlessness. When analysed in association with measurements of dynamic inspiratory constraints, a high V'E/V'CO2 is valuable to ascertain a role for the "lungs" in limiting dyspnoeic patients. Regardless of disease severity, cardiocirculatory (heart failure and pulmonary hypertension) and respiratory (lung fibrosis) comorbidities can further increase V'E/V'CO2 A high V'E/V'CO2 is a predictor of poor outcome in lung resection surgery, adding value to resting lung hyperinflation in predicting all-cause and respiratory mortality across the spectrum of disease severity. Considering its potential usefulness, the V'E/V'CO2 should be valued in the clinical management of patients with COPD.

Diverse Right Ventricular Remodeling Evaluated by MRI and Prognosis in Eisenmenger Syndrome With Different Shunt Locations.

Congenital shunt location is related to Eisenmenger syndrome (ES) survival. Moreover, right ventricular (RV) remodeling is associated with poor survival in pulmonary hypertension. To investigate RV remodeling using comprehensive magnetic resonance imaging (MRI) techniques and identify its relationship with prognosis in ES subgroups classified by shunt location. Prospective observational study. Fifty-four adults with ES (16 with pre-tricuspid shunt and 38 with post-tricuspid shunt). 3.0 T/cine MRI with balanced steady-state free precession sequence, late gadolinium enhancement with inversion recovery segmented gradient echo sequence and phase-sensitive reconstruction, and T1 mapping with modified Look-Locker inversion recovery sequence. Demographics, clinical characteristics, hemodynamics, RV remodeling features (morphology, systolic function, RV-pulmonary artery (PA) coupling and myocardial fibrosis), and prognosis were compared between ES subgroups. The adverse endpoint was all-cause mortality or readmission for heart failure. The independent samples t-test, Fisher's exact test or Chi-squared test, and the Kaplan-Meier method were used. P < 0.05 was considered significant. Compared to patients with post-tricuspid shunt, patients with pre-tricuspid shunt were significantly older and had higher N-terminal pro-B-type natriuretic peptide concentrations and poorer exercise tolerance. Pre-tricuspid shunt showed significantly larger RV dimensions (end-diastolic volume index: 185.81 ± 37.49 vs. 98.20 ± 36.26 mL/m2 ), worse RV ejection fraction (23.54% ± 12.35% vs. 40.82% ± 10.77%), and RV-PA decoupling (0.35 ± 0.31 vs. 0.72 ± 0.29). Biventricular myocardial fibrosis was significantly more severe in pre-tricuspid shunt than post-tricuspid shunt (extracellular volume, left ventricle: 35.85% ± 2.58% vs. 29.10% ± 5.20%; RV free wall: 30.93% ± 5.65% vs. 26.75% ± 5.15%). In addition, pre-tricuspid shunt demonstrated a significantly increased risk of adverse endpoint (hazard ratio: 2.938, 95% confidence interval: 1.204-7.172). ES with pre-tricuspid shunt might be a unique subtype with worse clinically decompensated RV remodeling and poor prognosis. 2 Technical Efficacy Stage: 5.

Expert consensus and operational guidelines on exercise rehabilitation of chronic obstructive pulmonary disease with integrating traditional Chinese medicine and Western medicine.

Chronic obstructive pulmonary disease (COPD) has become a widespread global chronic respiratory disease. In view of the large patient population, high mortality and disability rate, and heavy medical burden, COPD has become a major challenge for public health worldwide. According to epidemiological studies and demographic data, the prevalence of COPD in China is 13.7% and the number of COPD patients has reached more than 100 million. Therefore, it is of considerable significance to make more efforts to prevent and treat COPD (1). COPD is a chronic respiratory disease with dyspnea as its main clinical manifestation, especially during physical activity. COPD is often associated with cardiovascular, motor, metabolic and other systemic diseases, and may lead to pathological changes in many other systems (2). Muscle dysfunction is the most common extrapulmonary change that may influence the skeleton and respiratory muscles. Muscle dysfunction can lead to amyotrophy, muscle weakness, and other symptoms, which influence the skeletal muscle most significantly and result in poor exercise tolerance in patients (3). The pathological changes in skeletal muscle and dyspnea reduce the participation of activities in COPD patients and cause secondary muscle atrophy. These factors can result in declining motor ability, which is the critical predictor of mortality in COPD patients (4). COPD can influence patients’ health and quality of life. Delaying disease progression, alleviating symptoms, improving psychological status, and enhancing quality of life are the main goals of medical interventions for COPD patients. Pulmonary rehabilitation, as an indispensable part of effective treatments, is a multidisciplinary management program targeted at COPD patients to control disease progression, improve quality of life, and reduce the hospitalization rate (5). Exercise treatment, as the core of rehabilitation programs, has a higher degree of evidence in pulmonary rehabilitation that can improve dyspnea symptoms, increase motor abilities, and be helpful for improving psychological disorders and enhancing quality of life (3,6,7). To better guide exercise rehabilitation treatment for COPD patients, and to provide a systematic and operational plan for community doctors, pulmonary doctors and other health care providers on rehabilitation treatment, evaluation, treatment and follow-up, an expert group on respiratory rehabilitation and a professional committee on respiratory rehabilitation of the China Medical Education Association formed a common understanding by searching domestic and foreign studies, consulting with experts, and discussion. This consensus is based on existing research to develop a declarative document, focusing on the feasibility of our current clinical reality. In clinical practice, we still need to consider each patient’s specific situation to design individualized exercise rehabilitation programs. We present the following article in accordance with the RIGHT reporting checklist (available at https://dx.doi.org/10.21037/jtd-21-431).

6-month multidisciplinary follow-up and outcomes of patients with paediatric inflammatory multisystem syndrome (PIMS-TS) at a UK tertiary paediatric hospital: a retrospective cohort study

Paediatric inflammatory multisystem syndrome temporally associated with SARS-CoV-2 (PIMS-TS) is a new, rare, post-infectious complication of SARS-CoV-2 infection in children. We aimed to describe the 6-month outcomes of PIMS-TS. This retrospective cohort study comprised children (aged <18 years) who fulfilled the UK Royal College of Paediatrics and Child Health (RCPCH) diagnostic criteria for PIMS-TS and were admitted to Great Ormond Street Hospital (London, UK) between April 4 and Sept 1, 2020. Patients were followed up by a multidisciplinary team of specialists at 6 weeks and 6 months after admission. Biochemical and functional outcomes were analysed. 46 children were included in this study. The median age at presentation was 10·2 years (IQR 8·8-13·3), 30 (65%) patients were male and 16 (35%) were female, 37 (80%) were from minority ethnic groups, and eight (17%) had pre-existing comorbidities. All patients had elevated markers of systemic inflammation at baseline. None of the patients died. By 6 months, systemic inflammation was resolved in all but one patient. 38 (90%) of 42 patients who had positive SARS-CoV-2 IgG antibodies within 6 weeks of admission remained seropositive at 6 months. Echocardiograms were normal in 44 (96%) of 46 patients by 6 months, and gastrointestinal symptoms that were reported in 45 (98%) of 46 patients at onset were present in six (13%) of 46 patients at 6 months. Renal, haematological, and otolaryngological findings largely resolved by 6 months. Although minor abnormalities were identified on neurological examination in 24 (52%) of 46 patients at 6 weeks and in 18 (39%) of 46 at 6 months, we found minimal functional impairment at 6 months (median Expanded Disability Status Scale score 0 [IQR 0-1]). Median manual muscle test-8 scores improved from 53 (IQR 43-64) during hospital admission to 80 (IQR 68-80) at 6 months, but 18 (45%) of 40 patients showed 6-min walk test results below the third centile for their age or sex at 6 months. PedsQL responses revealed severe emotional difficulties at 6 months (seven [18%] of 38 by parental report and eight [22%] of 38 by self report). 45 (98%) of 46 patients were back in full-time education (virtually or face to face) by 6 months. Despite initial severe illness, few organ-specific sequelae were observed at 6 months. Ongoing concerns requiring physical re-conditioning and mental health support remained, and physiotherapy assessments revealed persisting poor exercise tolerance. Longer-term follow-up will help define the extended natural history of PIMS-TS. None.

Markers of Right Ventricle Dysfunction Predict Exercise Capacity on Left Ventricular Assist Device (LVAD) Patients

<h3>Purpose</h3> Although Left Ventricular Assist Device (LVAD) improves functional capacity, on average LVAD patients are unable to achieve the aerobic capacity of normal healthy subjects or mild heart failure patients. The aim of this study was to examine if markers of right ventricular (RV) function influence maximal exercise capacity. <h3>Methods</h3> This was a single-centre prospective study that enrolled 20 consecutive HeartWare ventricular assist device (HVAD) patients who were admitted at the Freeman Hospital (Newcastle upon Tyne, United Kingdom) for a heart transplant assessment from August 2017 to October 2018. <h3>Results</h3> Mean peak oxygen consumption (Peak VO₂) was 14.0 ± 5.0 ml/kg/min, and mean peak age and gender-adjusted percent predicted oxygen consumption (%VO₂) was 40.0 ± 11.5 %. Patients were subdivided into 2 groups based on the median peak VO₂, so each group consisted of 10 patients (50%). Right-sided and pulmonary pressures were consistently higher in the group with poorer exercise tolerance. Patients with poor exercise tolerance (peak VO₂ below the median) had higher right atrial pressures at rest (10.6mmHg ± 6.4 versus 4.3mmHg ± 3.2, p=0.02) and the increase with passive leg raising was significantly greater than those with preserved exercise tolerance (peak VO₂ above the median). Patients with poor functional capacity also had greater RV dimensions (4.4 cm ± 0.5 versus 3.7 cm ± 0.5, p=0.02) and a higher incidence of significant tricuspid regurgitation (TR) (moderate or severe TR in 5 patients in the poor exercise capacity group versus none in the preserved exercise capacity group, p=0.03). <h3>Conclusion</h3> Echocardiographic and hemodynamic markers of RV dysfunction discriminate between preserved and non-preserved exercise capacity in HVAD patients.

Interval Hypoxic Training in Rehabilitation Program for Adolescents with Overweight / Obesity and Comorbid Arterial Hypertension: Open-Label Randomized Study

Background. Searching for new strategies for the rehabilitation of adolescents with obesity and comorbid arterial hypertension (AHT) before significant pathological changes development in the cardiovascular system remains the urgent challenge.Objective. The aim of the study was to examine the effect of interval hypoxic training (IHT) on blood pressure (BP) levels in adolescents with overweight / obesity and comorbid AHT.Methods. Adolescents aged 14-17 years with body mass index SDS ≥ 1 and grade I AHT (mean level of systolic and/or diastolic BP ≥ 95th percentile for population of corresponding age, sex and height) have been randomized to the group «aerobic training» (treadmill walking) and “aerobic training + IHT” (usage of hypoxicator in intermittent operation cycles). All patients were on subcaloric diet (10% reduction in caloric intake for given age). Primary outcome measure was the difference between groups on systolic/diastolic BP levels according to 24-hour BP monitoring after completion of training program (10 classes each). The effects of IHT on body composition (bioelectrical impedance analysis), heart rate variability and psychoemotional state (Spielberger scale, assessment of health, activity and mood) were further estimated.Results. 43 patients were assigned to the index group, and 42 — to the control group. 67 patients have completed the research program. 5 patients (12%) from the IHT group and 13 patients (31%; p = 0.029) from the control group prematurely discontinued participation in the trial due to poor exercise tolerance. The groups were comparable in baseline systolic and diastolic BP. Decrease in BP occurred in both groups after 10 workouts. There were no differences in decrease value: mean difference for SBP was 2.4 mm Hg (95% CI -6.6 ... 1.8), for DBP — 0.2 mm Hg (-3.6 ... 4.0). However, the incidence of reaching the targeted SBP (&lt; 95th percentile for the corresponding age and sex) after completion of the treatment was recorded in 66% patients in the experimental group and in 42% patients in the control group (p = 0,047). Positive dynamics in several indicators of heart rate variability and psychoemotional state were mentioned in the IHT group.Conclusion. The IHT implementation in the complex of rehabilitation program for adolescents with overweight / obesity and AHT has no additional positive effect on BP levels. However, the incidence of reaching the targeted SBP (&lt; 95th percentile for the corresponding age and sex) after completion of the treatment was recorded in 66% patients in the experimental group and in 42% patients in the control group (p = 0,054).

A New Disease With Unknown Sequelae: Six-Month Multidisciplinary Follow-Up and Outcomes of Paediatric Inflammatory Multisystem Syndrome (PIMS-TS) Patients at a UK Tertiary Paediatric Centre

Background: Paediatric inflammatory multisystem syndrome temporally associated with SARS-CoV-2 (PIMS-TS), a new, rare post-infectious complication of SARS-CoV-2, was first defined by the Royal College of Paediatrics and Child Health in April 2020. The natural history of PIMS-TS is unknown. Methods: Children (<18 years old) meeting diagnostic criteria for PIMS-TS were followed up by a multidisciplinary team of specialists at regular intervals over 6 months after their acute admission. Findings: 46 children were identified. Median age at presentation was 10·2 years (IQR 8·8-13·3), 65·2% were male and 80·4% from ethnic minority groups. Systemic inflammation resolved in all. 90·5% (38/42) whom had positive SARS-CoV-2 IgG within six weeks of admission remained seropositive at six months. Echocardiograms were normal in 96% at six months. Gastrointestinal symptoms, although present in 95·7% at onset were minimal in follow-up (6·5%). Objective renal, haematology, and otolaryngology findings largely resolved by six months. Whilst minor abnormalities on neurological exam were identified in 52·2% and 39·1% at six weeks and six months respectively, we found no functional impairment by Expanded Disability Status Scale (six-month median score 0, IQR 0-1). Physiotherapy assessment revealed persisting poor exercise tolerance. Despite improvement in median manual muscle test-8 scores from 53/80 (IQR 43-64) during hospitalisation to 80/80 (IQR 68-80), 45% demonstrated six-minute walk test results <3 rd centile for age/sex at six months. Parental (19%) and self-report (22%) revealed severe emotional difficulties at six months. 31·1% of parents reported anxiety about possible PIMS-TS relapse in their child with 20% taking additional isolation precautions and 22·2% were concerned about ongoing medical vulnerability. 97·8% patients were back in full-time education by six months. Interpretation: Despite initial severe illness, by six months few organ-specific sequelae were observed. Ongoing concerns requiring physical re-conditioning and mental health support remained. Longer-term follow-up will help define the extended natural history of PIMS-TS. Funding Statement: None to declare. Declaration of Interests: AB declares consultancy work for Gilead Inc. within the past three years of which the role did not impact on the writing of this manuscript. The remainder of authors have no declarations of interest to declare. Ethics Approval Statement: As the data analysis was retrospective and no additional data were collected beyond those required for standard medical care, a full ethics review under the terms of the Governance Arrangements of Research Ethics Committees in the UK was not required. A clinical audit was registered with GOSH NHS Foundation Trust Audit Committee (#2857).

Combined Echocardiographic and Cardiopulmonary Exercise to Assess Determinants of Exercise Limitation in Chronic Obstructive Pulmonary Disease

Current methods do not allow a thorough assessment of causes associated with limited exercise capacity in patients with chronic obstructive pulmonary disease (COPD). Twenty patients with COPD and 20 matched control subjects were assessed using combined cardiopulmonary and stress echocardiographic testing. Various echocardiographic parameters (left ventricular [LV] volumes, right ventricular [RV] area, ejection fraction, stroke volume, S', and E/e' ratio) and ventilatory parameters (peak oxygen consumption [Vo2] and A-Vo2 difference) were measured to evaluate LV and RV function, hemodynamics, and peripheral oxygen extraction (A-VO2 difference). Significant differences (both between groups and for group-by-time interaction) were seen in exercise responses (LV volume, RV area, LV volume/RV area ratio, S', E/e' ratio, tricuspid regurgitation grade, heart rate, stroke volume, and Vo2). The major mechanisms of reduced exercise tolerance in patients with COPD were bowing of the septum to the left in 12 (60%), abnormal increases in E/e' ratio in 12 (60%), abnormal stroke volume reserve in 16 (80%), low peak A-Vo2 difference in 10 (50%), chronotropic incompetence in 13 (65%), or a combination of several mechanisms. Patients with COPD and poor exercise tolerance showed attenuated increases in stroke volume, heart rate, and A-Vo2 difference and exaggerated changes in LV/RV ratio and LV compliance (ratio of LV volume to E/e' ratio) compared with patients with COPD with good exercise tolerance. Combined cardiopulmonary and stress echocardiographic testing can be helpful in determining individual mechanisms of exercise intolerance in patients with COPD. In patients with COPD, exercise intolerance is predominantly the result of chronotropic incompetence, limited stroke volume reserve, exercise-induced elevation in left filling pressure, and peripheral factors and not simply obstructive lung function. Limited stroke volume is related to abnormal RV contractile reserve and reduced LV compliance introduced through septal flattening and direct ventricular interaction.

Preoperative right ventricular strain predicts sustained right ventricular dysfunction after balloon pulmonary angioplasty in patients with chronic thromboembolic pulmonary hypertension

Balloon pulmonary angioplasty (BPA) improves hemodynamics and exercise tolerance in patients with chronic thromboembolic pulmonary hypertension (CTEPH). However, its diagnostic and predictive values remain unclear. We investigated the diagnostic and predictive values of BPA by assessing the mechanism of right ventricular (RV) dysfunction. Hemodynamic improvement was maintained over 6months in 99 patients with CTEPH who underwent BPA. Notably, 57 of 99 patients showed normalization of pulmonary vascular resistance (PVR) after BPA. The RV mid free wall longitudinal strain (RVMFS) was inversely correlated with the 6-min walk distance (r=-.35, P=.01) and serum levels of high-sensitivity cardiac troponin T (hs-cTNT) (r=-.39, P=.004) 6months post-BPA in the PVR-normalized group. Among all variables analyzed, only the pre-BPA RVMFS was correlated with the post-BPA RVMFS (r=.40, P=.001), and the pre-BPA RVMFS (<-15.8%) was the strongest predictor of post-BPA normalization of RVMFS (area under the curve 0.80, P=.01, sensitivity 89%, and specificity 63%). The immediate post-BPA RVMFS showed worsening over 6months after the procedure (-25.8% to -21.1%) in patients with high serum hs-cTNT levels (>0.0014ng/mL). In contrast, we observed an improvement in these values in those with low serum hs-cTNT levels (-23.6% to -24.4%). RVMFS of -15.8% may be a useful cutoff value to categorize the refractory and non-refractory stages of disease. Sustained serum hs-cTNT elevation post-BPA indicates subclinical RV myocardial injury, with resultant RVMFS deterioration and poor exercise tolerance.

Markers of Right Ventricular Dysfunction Predict Maximal Exercise Capacity After Left Ventricular Assist Device Implantation.

Although left ventricular assist device (LVAD) improves functional capacity, on average LVAD patients are unable to achieve the aerobic capacity of normal healthy subjects or mild heart failure patients. The aim of this study was to examine if markers of right ventricular (RV) function influence maximal exercise capacity. This was a single-center prospective study that enrolled 20 consecutive HeartWare ventricular assist device patients who were admitted at the Freeman Hospital (Newcastle upon Tyne, United Kingdom) for a heart transplant assessment from August 2017 to October 2018. Mean peak oxygen consumption (Peak VO2) was 14.0 ± 5.0 ml/kg/min, and mean peak age and gender-adjusted percent predicted oxygen consumption (%VO2) was 40.0% ± 11.5%. Patients were subdivided into two groups based on the median peak VO2, so each group consisted of 10 patients (50%). Right-sided and pulmonary pressures were consistently higher in the group with poorer exercise tolerance. Patients with poor exercise tolerance (peak VO2 below the median) had higher right atrial pressures at rest (10.6 ± 6.4 vs. 4.3 mmHg ± 3.2; p = 0.02) and the increase with passive leg raising was significantly greater than those with preserved exercise tolerance (peak VO2 above the median). Patients with poor functional capacity also had greater RV dimensions (4.4 cm ± 0.5 vs. 3.7 cm ± 0.5; p = 0.02) and a higher incidence of significant tricuspid regurgitation (moderate or severe tricuspid regurgitation in five patients in the poor exercise capacity group vs. none in the preserved exercise capacity group; p = 0.03). In conclusion, echocardiographic and hemodynamic markers of RV dysfunction discriminate between preserved and nonpreserved exercise capacity in HeartWare ventricular assist device patients.

S3285 The Negative Predictive Value of Dobutamine Stress Echocardiography for Identifying Coronary Artery Disease in Liver Transplant Evaluation

INTRODUCTION: Coronary artery disease (CAD) is associated with increased morbidity and mortality in end-stage liver disease (ESLD) patients undergoing liver transplant(LT). Dobutamine stress echocardiography (DSE) has gained preference over other screening tests for detecting CAD in ESLD patients due to the chronic systemic vasodilatation, increased cardiac output, and poor exercise tolerance. This study aimed to evaluate the negative predictive value and the accuracy of DSE for the diagnosis of obstructive CAD, using coronary angiography as the reference in ESLD patients. METHODS: This is a retrospective single-center study at Methodist University Hospital, Memphis TN, which included patients with ESLD undergoing LT evaluation. We reviewed patients from three consecutive years and identified the patients who underwent DSE as part of pre-transplant evaluation along with coronary angiography within six months of DSE. A total of 94 patients were identified that had both a DSE along with coronary angiography for LT evaluation. Beta-blockers were held prior to DSE, and the target heart rate for DSE was 85% age-predicted maximum heart rate. Of the 94 patients, nine patients did not achieve a maximal heart rate despite maximal medication. An analysis was performed with the remaining 85 patients. Patients were referred for coronary angiography if DSE was abnormal or with a normal DSE in the presence of ≥1 risk factor(s) for CAD. Significant CAD was defined as ≥70% obstruction or fractional flow reserve < 0.80. RESULTS: A total of 22 patients had a DSE positive test and were referred to coronary angiography: 5/22(23%) patients had positive coronary angiography and 18/22(82%) had negative coronary angiography. The sensitivity in this group was 63% and specificity of 78%. Interestingly, 63 patients were referred for coronary angiography with a negative DSE due to CAD risk factors: 3/63(5%) patients had a positive coronary angiography, and 60/63(95%) patients had a negative coronary angiography. The negative predictive value of DSE at detecting obstructive CAD in ESLD patients is 95% (Table 1). The accuracy of DSE at detecting obstructive CAD in ESLD patients is 76%. CONCLUSION: Due to the hemodynamics of the ESLD patients, the sensitivity of DSE is limited. However, the negative predictive value is high (95%) to use DSE as a cost-effective, non-invasive screening test to rule out CAD.Table 1

Diaphragmatic excursion correlates with exercise capacity and dynamic hyperinflation in COPD patients.

BackgroundAlthough the pathophysiological mechanisms involved in the development of dyspnoea and poor exercise tolerance in patients with COPD are complex, dynamic lung hyperinflation (DLH) plays a central role. Diaphragmatic excursions can be measured by ultrasonography (US) with high intra- and interobserver reliability. The objective of this study was to evaluate the effect of diaphragmatic excursions as assessed by US on exercise tolerance and DLH in patients with COPD.MethodsPatients with COPD (n=20) and age-matched control subjects (n=20) underwent US, which was used to determine the maximum level of diaphragmatic excursion (DEmax). Ventilation parameters, including the change in inspiratory capacity (ΔIC), were measured in the subjects during cardiopulmonary exercise testing (CPET). We examined the correlations between DEmax and the ventilation parameters.ResultsThe DEmax of patients with COPD was significantly lower than that of the controls (45.0±12.8 mm versus 64.6±6.3 mm, respectively; p<0.01). The perception of peak dyspnoea (Borg scale) was significantly negatively correlated with DEmax in patients with COPD. During CPET, oxygen uptake/weight (V′O2/W) and minute ventilation (V′E) were significantly positively correlated with DEmax, while V′E/V′O2 and V′E/carbon dioxide output (V′CO2) were significantly negatively correlated with DEmax in patients with COPD. DEmax was also significantly positively correlated with ΔIC, reflecting DLH, and with V′O2/W, reflecting exercise capacity.ConclusionReduced mobility of the diaphragm was related to decreased exercise capacity and increased dyspnoea due to dynamic lung hyperinflation in COPD patients.

PROBLEMATIC PECTORIS: A CASE OF FEMORAL VENOUS ACCESS FOR PACEMAKER PLACEMENT

SESSION TITLE: Medical Student/Resident Cardiovascular Disease Posters SESSION TYPE: Med Student/Res Case Rep Postr PRESENTED ON: October 18-21, 2020 INTRODUCTION: A permanent pacemaker (PPM) is an electrical device that is utilized to sustain an appropriate heart rate in individuals who have symptoms, due to bradyarrhythmias, ranging from dizziness, syncope, fatigue, poor exercise tolerance to even death. It is commonly implanted in the pre-pectoral position and connected to transvenous leads through the subclavian vein. Below, we present a case of a patient with Poliomyelitis requiring crutches to ambulate and contraindications to traditional PPM implantation. CASE PRESENTATION: A 72-year old female with history of paroxysmal atrial fibrillation on rivaroxaban, mitral regurgitation and poliomyelitis had been admitted to the hospital with episodes of dizziness, lightheadedness, fatigue and exertional chest pain with heart rate in the 40-50 beats per minute. She underwent cardiac catheterization which did not show significant coronary artery disease. Once she was asymptomatic, she was discharged home on a reduced dose of Carvedilol from 12.5 mg twice a day( bid) to 3.125 mg bid. Her heart rate was still noted to have 40 to 42 bpm upon follow up with a cardiac electrophysiologist (EP) three months post hospitalization. She reported mild exertional dyspnea, so her carvedilol was discontinued and was recommended to have a PPM implanted. The patient had concerns in regards to having a pectoral PPM placed as she relied on the use of crutches to support her during ambulation due to her history of poliomyelitis. The option of having a PPM placed via the femoral vein was discussed along with the rarity of the procedure, risks and benefits. The patient underwent femoral dual chamber device implantation via the right femoral vein and the PPM was placed above the right groin crease down to the pre-external oblique fascia. The patient was discharged after successful interrogation of the device. Her symptoms had resolved on her one month follow up with the EP outpatient. Her pacemaker interrogation revealed 98% atrial pacing. DISCUSSION: Permanent PM is conventionally placed via pectoral approach with contraindications in about 1-6% cases. Alternative approach via femoral approach is a viable option at that time. Some of the advantages would be site availability, lower bleeding risk, ability to perform under local anesthesia. Disadvantages of femoral approach is risk of retroperitoneal hematoma due to erroneous arterial puncture, atrial lead dislodgement. CONCLUSIONS: This case highlights the advantages of PPM placed via femoral vein as it provides an alternate method for individuals who have contraindications to having PPM placed using the traditional route via the subclavian vein. The concern of using crutches and its proximity of the PPM was thus resolved with using this methodology. With the emergence of more case reports highlighting the advantages and success rates of this procedure, PPM placement via the femoral vein may soon become routine practice. Reference #1: •Mathur G, Stables RH, Heaven D, Ingram A, Sutton R. Permanent pacemaker implantation via the femoral vein: an alternative in cases with contraindications to the pectoral approach. Europace. 2001;3:56–59. doi: 10.1053/eupc.2000.0135. Reference #2: •Sutton R, Vardas P. Special surgical techniques in pacemaker implantation, Pacing Clin Electrophysiol, 1987, vol. 10 pg. 749 Reference #3: •Yamaguchi T, Miyamoto T, Yamauchi Y, et al. A case report of successful permanent pacemaker implantation via the iliac vein. J Arrhythm 2016;32:151–3 DISCLOSURES: Consultant relationship with Biosense Webster - Johnsosn & Johnson; Meddtronic Please note: $1001 - $5000 Added 06/02/2020 by Devender Akula, source=Web Response, value=Honoraria no disclosure on file for Rahul Anil; No relevant relationships by Rhea Farquhar, source=Web Response No relevant relationships by URMIL PATEL, source=Web Response

Reproducibility of the 6-Min Step Test in Subjects With COPD.

Test-retest reproducibility of the 6-min step test (6MST) is controversial in patients with COPD because the decision to perform a second test is influenced by interruptions, physiological overload, and the patient's exercise tolerance. The aim of this study was to analyze the reproducibility of performance on the 6MST (ie, number of steps climbed and interruptions) and physiological variables in subjects with COPD, with and without poor exercise tolerance, and with and without interruptions during the test. Subjects performed 2 6MST (6MST1, 6MST2) with a minimum of 30 min rest between tests. Physiological variables were assessed with a gas analyzer. Subjects who performed ≤ 78 steps in the 6MST1 and ≤ 86 steps in the test with the higher number of steps performed (6MSTBEST) were considered to have poor exercise tolerance. Subjects were also stratified according to those who interrupted the 6MSTBEST and those who did not interrupt the 6MSTBEST. 40 subjects (31 men; FEV1 percent of predicted = 50.4 ± 13.5) participated in the study. The number of steps, interruptions, and physiological variables showed moderate to high reliability (intraclass correlation coefficient: 0.70-0.99, P < .001). Thirty-one (77.5%) subjects had a better performance during 6MST2 than 6MST1 (mean difference: 4.65 ± 5.59, P < .001). Although the number of times subjects were interrupted was similar between the 2 tests (P = .66), the duration of these interruptions was shorter during 6MST2 (mean difference: -0.12 ± 0.39 s, P = .040). The difference in the number of steps (6MST2 - 6MST1) did not differ between subjects who performed ≤78 steps (mean difference: 5.64 ± 5.32 steps; 10.3%; P < 0.001) and ≥ 79 steps (3.00 ± 5.82 steps; 6.13%; P = 0.08) on the 6MST1 (P = 0.15) and between subjects who performed ≤ 86 steps (5.39 ± 5.14 steps; 9.39%; P < 0.001) and ≥ 87 steps (2.92 ± 6.43 steps; 2.74%; P = 0.14) steps on the 6MSTBEST (P = 0.20). Performance and physiological variables in the 6MST were reproducible, and a second test did not impose greater physiological overload. Two tests were essential for patients with poor exercise tolerance.

Study of cardiovascular manifestations in treatment naive HIV patients and patients on HAART and its correlation with CD4+ cell counts in a tertiary care centre

Background: Highly active anti-retroviral therapy (HAART) increases the longevity of the patients infected with Human immunodeficiency virus (HIV) so mortality due to opportunistic infections is reducing and late complications like cardiovascular manifestations are on its rise. Cardiac involvement can be over-looked in HIV positive patients because symptoms of breathlessness, fatigue and poor exercise tolerance are ascribed to other conditions associated with HIV patients. Objective: Primary objective was to evaluate cardiac manifestations and determine type of cardiac involvement in both HAART naïve patients and patients on HAART and correlate with CD4+ counts. Methods: 200 HIV infected patients presenting in outpatient department (OPD) and inpatients are included. Information is collected and detailed history is taken using pre-formed proforma. At the time of admission or follow up, steps are taken to send for all the investigations and detailed clinical examination of the patient done, focusing more on cardiovascular system. Results: 41% of the patients with normal cardiac function were not on HAART and 62.7% of the patients with cardiac dysfunction were HIV naïve and it was found to be statistically significant (p value 0.003). Tricuspid regurgitation (42.1% verus 57.9%, p value 0.035) and Ischemic heart disease (IHD) (0% versus 100% p value 0.049) found to have significant association in patients who were on HAART. Systolic dysfunction (p value 0.048) and IHD (p value 0.019) were both significantly associated with the low CD4+ counts in patients not on HAART. Conclusion: There was significant association of HAART on the occurrence of cardiac dysfunction. Cardiac dysfunction is noted with low CD4+ counts, it is therefore important to undergo 2-dimensional echocardiography (2-D Echo) at diagnosis and at regular intervals in all HIV infected patients and to initiate early treatment for the same.the rural population.

Diagnosis, prevalence, and clinical impact of sarcopenia in COPD: a systematic review and meta-analysis.

Sarcopenia prevalence and its clinical impact are reportedly variable in chronic obstructive pulmonary disease (COPD) due partly to definition criteria. This review aimed to identify the criteria used to diagnose sarcopenia and the prevalence and impact of sarcopenia on health outcomes in people with COPD. This review was registered in PROSPERO (CRD42018092576). Five electronic databases were searched to August 2018 to identify studies related to sarcopenia and COPD. Study quality was assessed using validated instruments matched to study designs. Sarcopenia prevalence was determined using authors' definitions. Comparisons were made between people who did and did not have sarcopenia for pulmonary function, exercise capacity, quality of life, muscle strength, gait speed, physical activity levels, inflammation/oxidative stress, and mortality. Twenty‐three studies (70% cross‐sectional) from Europe (10), Asia (9), and North and South America (4) involving 9637 participants aged ≥40 years were included (69.5% men). Sarcopenia criteria were typically concordant with recommendations of hEuropean and Asian consensus bodies. Overall sarcopenia prevalence varied from 15.5% [95% confidence interval (CI) 11.8–19.1; combined muscle mass, strength, and/or physical performance criteria] to 34% (95%CI 20.6–47.3; muscle mass criteria alone) (P = 0.009 between subgroups) and was greater in people with more severe [37.6% (95%CI 24.8–50.4)] versus less severe [19.1% (95%CI 10.2–28.0)] lung disease (P = 0.020), but similar between men [41.0% (95%CI 26.2–55.9%)] and women [31.9% (95%CI 7.0–56.8%)] (P = 0.538). People with sarcopenia had lower predicted forced expiratory volume in the first second (mean difference −7.1%; 95%CI −9.0 to −5.1%) and poorer exercise tolerance (standardized mean difference −0.8; 95%CI −1.4 to −0.2) and quality of life (standardized mean difference 0.26; 95%CI 0.2–0.4) compared with those who did not (P < 0.001 for all). No clear relationship was observed between sarcopenia and inflammatory or oxidative stress biomarkers. Incident mortality was unreported in the literature. Sarcopenia is prevalent in a significant proportion of people with COPD and negatively impacts upon important clinical outcomes. Opportunities exist to optimize its early detection and management and to evaluate its impact on mortality in this patient group.

Exercise Training in Patients With Heart Failure With Preserved Ejection Fraction: A Community Hospital Pilot Study.

Patients with heart failure with preserved ejection fraction (HFpEF) experience poor exercise tolerance and quality of life. Little is known about the feasibility or effects of HFpEF exercise training (ET) in a community hospital setting. The aim of this study was to examine the feasibility and pilot data of a community-based HFpEF ET intervention. This was a single-group (n = 16), pretest-posttest, 9-week ET intervention. The Minnesota Living With Heart Failure Questionnaire, Patient Health Questionnaire-9, cardiopulmonary exercise test (peak VO2), and 6-minute walk test were used for evaluation. Participants (n = 16) attended 88% of prescribed ET sessions and 94% completed all pretest-posttest assessments. Significant improvements in Minnesota Living With Heart Failure Questionnaire (P = .01), Patient Health Questionnaire-9 (P ≤ .01), exercise test time (P = .01) and 6-minute walk test (P = .001), but not in peak VO2 (P = .16), were found. The ET intervention was feasible and safe, and findings support improved quality of life, depressive symptoms, and exercise tolerance. Larger controlled trials are warranted.