Treadmill Exercise Stress Test Research Articles

Vext - A Virtual Exercise Training Program For Pediatric Solid Organ Transplant Recipients: A Feasibility Study.

Pediatric solid organ transplant (SOT) recipients report lower strength and physical activity levels than their healthy peers. Virtual exercise programs may reduce barriers to exercise and allow for additional access to specialized care. PURPOSE: To determine the feasibility of an 8-week virtual exercise program (VEXT) in pediatric solid organ transplant recipients. METHODS: A strength-based program was designed by a clinical exercise physiologist (AD). A treadmill exercise stress test was completed prior to starting the program. Self-report surveys were used to assess quality of life (Pediatric Quality of Life Inventory, PedsQL), fatigue (Pediatric Quality of Life Multidimensional Fatigue Scale, PedsQL-Fatigue), and physical activity (Physical Activity Questionnaire for Children and Adolescents, PAQ-C/A) prior to and after completion of the program. The strength sub-test of the Bruininks-Oseretsky Test of Motor Proficiency (BOT-2) was administered virtually. Classes were conducted via Zoom (Zoom Video Communications Inc, San Jose, CA), 3 times per week for 30 minutes. Weekly engagement with the study team was provided by a web-based text messaging platform (WelTel Inc., Vancouver, BC). Medians (inter-quartile range, IQR) are reported. RESULTS: Baseline findings are reported for 12 participants (4 liver, 5 kidney, 3 heart SOT recipients; 58% females). The median age was 12 (11-14) years. PedsQL score was [69.57 (55.98-79.89); Normal: 85.66 ± 11.99]. PedsQL-Fatigue score was [66.67 (45.84-76.89); Normal: 82.19 ± 12.27]. PAQ-C/A score was [Females: 1.72 (1.27-2.11); Normal: 2.70 ± 0.63, Males: 2.87 (2.60-2.87); Normal: 3.01 ± 0.72]. The median strength subtest Z-score was -1.00 (-1.35 to -0.60). Exercise times for 10 of the participants who followed the BCCH protocol was 7.04 minutes [(5.68 - 8.86); Controls: 15.25 (13.82 - 16.75)]. The remaining 2 participants followed a modified protocol due to physical limitations. CONCLUSIONS: At baseline, pediatric SOT recipients report a lower quality of life, higher fatigue, and lower physical activity levels than healthy children. Eleven of twelve participants have a low strength score. A virtual exercise program may help to increase strength, increase physical activity levels and, in turn, may improve quality of life in these children.

Exercise Capacity and Perceived Exertion on Treadmill Stress Test Performed While Wearing vs Without a Surgical Mask: A Randomized Clinical Trial in Healthy Adults

BackgroundThe graded exercise treadmill stress test (GXT) is among the most frequently performed tests in cardiology. The COVID-19 pandemic led many healthcare facilities to require patients to wear a mask during the test. This study evaluated the effect of wearing a surgical face mask on exercise capacity and perceived exertion. MethodsIn this prospective, randomized crossover trial, 35 healthy adults performed a GXT using the Bruce protocol while wearing a surgical mask, and without a mask. The primary outcome was exercise capacity in metabolic equivalents (MET), and the secondary outcome was exercise perception on the modified Borg scale (from 0 to 10). Effort duration, heart rate, oxygen saturation, and blood pressure were also analyzed. ResultsExercise capacity was reduced by 0.4 MET (95% confidence interval [CI] –0.7 to –0.2) during the GXT with a mask (11.8 ± 2.7 vs 12.3 ± 2.5 MET, P = 0.001), and the final perceived effort increased by 0.5 points (95% CI 0.2 to 0.8; 8.4 ± 1.3 vs 7.9 ± 1.6, P = 0.004). Effort duration was cut down by 24 seconds (CI –0:39 to –0:09; 10:03 ± 2:30 vs 10:27 ± 2:16 [minutes:seconds], P = 0.003). Oxygen saturation was slightly lower at the end of the test when participants wore a mask. No significant differences occurred in heart rate or blood pressure during the test. ConclusionWearing a surgical mask causes a statistically significant decrease in exercise capacity and increase in perceived exertion. This small effect is not clinically significant for the interpretation of test results.

Effects of Tobacco Consumption on Aerobic Fitness in Indian Adult Men

Background and Aim: Smokeless tobacco products like khaini, guthakha, betel quid, zarda are very commonly consumed by men and women of all age group followed by smoking of bidi, cigarette and hookah. Tobacco consumption is associated with poor cardiorespiratory, gastrointestinal and overall health. Compromised physical fitness is seen in tobacco consumers and severity depends on type of product and duration of use. Aerobic or cardiorespiratory fitness is compromised in tobacco consumers. This study was planned to check the effect of tobacco consumption on aerobic fitness of Indian adult men of 18 to 60 years of age group. Methods: Participants for this study were recruited from Pramukhswami Medical College and its affiliated institutes after obtaining permission from the Institutional Ethics Committee (IEC). A total 74 adult men of 18-60 years’ age groups were enrolled for the present study after their voluntary consent. A total 24 participants who consume tobacco were placed in study group and a total 50 participants who were not consuming tobacco products were placed control group. All participants were apparently healthy at the time of Treadmill exercise stress test following Bruce protocol. Predicted VO2 max (PVO2 max) was calculated on the basis of total exercise time in minutes and seconds on Treadmill machine as per Bruce’s formula of calculating indirect maximal oxygen consumption. Results: PVO2 max values obtained by Treadmill exercise test following Bruce protocol in study group was 29.16 ± 8.88 ml/kg/min while control group was 36.47 ± 9.7. A statistically significant reduction in aerobic fitness was seen in study group as compared to control group. Conclusion: Aerobic fitness was significantly less in tobacco consumer Indian adult men of 18-60 years’ age group as compared to who do not consume tobacco.

Parameters indicating development of hypertension in three-year follow-up study of subjects with high normal blood pressure

Abstract Funding Acknowledgements Type of funding sources: None. Background/Introduction The clinical importance of a hypertensive response to exercise (HRE) in subjects with high normal blood pressure (BP) is not fully elucidated, while sympathetic overactivity followed by arterial stiffening are linked with development of hypertension (HTN). Purpose The aim of this study was to assess the relation of HRE with sympathetic drive as assessed by muscle sympathetic nerve activity (MSNA) and arterial stiffness in subjects with high normal BP who developed hypertension in a 3 year follow up. Methods 100 subjects with high normal office BP [systolic BP=130-139 mmHg and diastolic BP=85-89 mmHg] underwent a treadmill exercise stress test. Arterial stiffness was evaluated based on carotid to femoral pulse wave velocity (PWV). Sympathetic drive was assessed by MSNA levels. Follow up was every 6 months for 3 years, where BP was measured at both office (OffBP) and ambulatory blood pressure monitoring (ABPM). All participants offered lifestyle advises. Endpoint was development of HTN diagnosed either from OffBP or from ABPM. Then they were divided into Group I: those developed HTN and Group II: those remained normotensive. Results Mean age 54±8 years, 42 males, baseline offBP: 132/82 mmHg, ABPM: 122/76 mmHg). Out of them, 50 subjects developed HRE (BP ³210mmHg in men and ³190 mmHg in women) and 40 HTN. Group I developed higher HRE (75% vs. 13%, p=0.026), higher levels of PWV (8.35 vs 7.5 m/sec, p=0.043) and MSNA levels (37 vs. 31 bursts, p=0.04), while did not differ at their metabolic profile. Echocardiographically left ventricular mass index did not differ statistically as E/A ratio of mitral valve inflow (0.92 vs 1.05, p=0.034). Those who developed HTN was related to night systolic BP from ABPM (116 vs 112 mmHg, p<0.04), as also to intermediate stage intervals of 3 min (160 vs 147 mmHg, p=0.068) and 6 min (181 vs 164, p=0.035) of Bruce protocol. A novel metric, the SBP/MET-slope [(peak SBP—resting SBP)/(peak MET-1)] found to add crucial information. Regarding those who developed HTN, SBP/MET-slope was higher in all stages till peak exercise (stage 1: 6.25 vs 4.25, stage 2: 7.6 vs 5.3, peak: 7.22 vs 5.1, p=0.035). It was noticed that they performed a higher exercise capacity (10 vs 11.5 METs) and additionally differ significantly in their maximal heart rate (HR) at peak exercise (154 vs 164, p=0.001). Conclusion In subjects with high normal BP, a HRE, the intermediate BP intervals along with the SBP/MET-slope, identifies a state of systemic vascular resistance, arterial stiffening and sympathetic overdrive, as reflected by increased PWV and MSNA levels respectively. Additionally, exercise capacity demonstrates cardiovascular functional tolerance. These findings suggest that exercise testing provides determining clinical information regarding the overall cardiovascular status, proving its superior prognostic value as a hypertension screening tool, that alarms the physician to warn the patient to take action.

Blood pressure response during treadmill exercise testing and the risk for future development of atrial fibrillation

Abstract Funding Acknowledgements Type of funding sources: None. Aims Hypertension is a well-established risk factor for the onset and progression of atrial fibrillation (AF). Blood pressure (BP) response during routine exercise stress testing (EST) may identify subjects at increased risk for developing AF. Methods A retrospective analysis of treadmill EST performed by the Bruce protocol in patients aged ≥40 years without a history of AF (n=17,617; 42% women). BP was measured at rest, peak exercise, and 2-minute recovery, and was analyzed for association with the risk for developing AF. Results AF was documented in 4.5% of patients during mean follow-up of 7 years. The incidence rate of AF per 1000 person-years increased with the rise in CHA2DS2VASc score (3.26 in score=0 to 19.78 in scores≥6). Adjusting for CHA2DS2VASc score and exercise capacity, a multivariate analysis of systolic BP at rest (≥130 vs. ≤110 mmHg), peak-exercise (>170 vs. ≤150 mmHg), and recovery (>150 vs. ≤130 mmHg), were associated with increased risk for AF: hazard ratio (HR) 1.68 (95% CI, 1.40-2.01), 1.38 (1.15-1.64), 1.54 (1.27-1.86), respectively. Similarly, diastolic BP analysis at rest (≥90 vs. <80 mmHg), peak-exercise (≥100 vs. <90 mmHg), and recovery (>90 vs. ≤80 mmHg), were associated with increased risk for AF: 1.78 (1.34-2.35), 2.22 (1.37-3.59), 1.73 (0.90-3.25). The association with AF was also observed when BPs were analyzed as continuous variables, including after additional adjustment of exercise and recovery measurements to resting BP. Conclusions Systolic and diastolic BP at rest, peak-exercise and recovery phases of EST may provide independent predictive information regarding future risk for developing AF.

PO-639-06 PROCEED WITH CAUTION: STANDARD PROTOCOL EXERCISE STRESS TESTS DO NOT RECREATE THE DIAGNOSTIC UTILITY OF THE SUPINE-STAND TESTS FOR LONG QT SYNDROME

The treadmill exercise stress test (TEST) can unmask concealed long QT syndrome (LQTS), especially LQT1, by identifying a maladaptive QT response during the TEST’s recovery phase. Additionally, the supine-stand test may aid in LQTS diagnosis as patients fail to shorten their QT interval in response to standing up, and instead show a paradoxical increase of QT. However, as the supine-stand test protocol requires patients to be supine and then standing for ≥ 5 minutes, this often does not match the standard TEST protocols and as such, the clinical utility needs to be validated.

Blood pressure measurements during treadmill exercise testing and the risk for the future development of atrial fibrillation.

Hypertension is a well-established risk factor for the onset and progression of atrial fibrillation (AF). Blood pressure (BP) measurements during routine exercise stress testing (EST) may identify subjects at increased risk for developing AF. We performed a retrospective analysis of treadmill EST carried out using the Bruce protocol in patients aged ≥40 years without a history of AF (n = 17,617; 42% women). BP was measured at rest, peak exercise, and 2-min recovery and analyzed for its association with the risk for developing AF. During a mean follow-up of 7 years, AF was documented in 4.5% of the patients. The incidence rate of AF per 1000 person-years increased with the rise in CHA2DS2VASc scores (3.26 for a Score=0 to 19.78 for scores ≥6). In a multivariate analysis, adjusting for risk score components and exercise capacity, systolic BP measurements taken at rest (≥130 vs. ≤110 mmHg), peak exercise (>170 vs. ≤150 mmHg), and recovery (>150 vs. ≤130 mmHg) were associated with an increased risk for AF: the hazard ratios (HRs) were 1.56 (95% CI, 1.30-1.87), 1.21 (1.01-1.45), and 1.33 (1.10-1.62), respectively. Similarly, diastolic BP measurements taken at rest (≥90 vs. <80 mmHg), peak exercise (≥100 vs. <90 mmHg), and recovery (>90 vs. ≤80 mmHg) were associated with an increased risk for AF: the HRs were 1.80 (1.36-2.38), 2.08 (1.28-3.37), and 1.56 (0.81-3.02), respectively. The association of exercise BP with AF was further observed when the BPs were analyzed as continuous variables and in subjects without a baseline diagnosis of hypertension. In conclusion, systolic and diastolic BP taken at the rest, peak exercise and recovery phases of EST may provide independent predictive information regarding future risk for developing AF.

Effect of treadmill exercise stress testing on troponin levels in children and adolescents.

Chest pain is a common complaint among paediatric patients and cardiac troponin (cTn) level is often part of the initial emergency department evaluation. It is well known that after intense endurance exercise cTn levels can be elevated in patients with otherwise healthy hearts, however the effect shorter duration exercise has on cTn levels in this population is not known. Determine the behaviour of cTn levels in healthy children and adolescent patients after short burst, high-intensity aerobic exercise. Patients without haemodynamically significant heart disease referred for a treadmill exercise stress test (EST) were recruited over a 6-month period. cTn levels were measured prior to exercise and 4 hours after exercise. Thirteen patients enrolled. Indications for EST were exertional syncope (six), chest pain (four), and long QT syndrome (three). The median exercise time was 12.9 (9.9-13.7) minutes with an average endurance at the fiftieth percentile for age and maximum heart rate rose to an average of 92 (74-98)% of the predicted peak for age. cTn levels prior to exercise were undetectable in all patients. There was no cTn rise in any patient after exercise. There were no ischaemic changes or arrhythmias on exercise electrocardiograms. Serum cTn levels do not rise significantly in healthy children after short duration, high-intensity aerobic exercise. Physicians evaluating paediatric patients with an elevated cTn level after less than prolonged strenuous activity likely cannot attribute this lab value solely to exercise and may need to undertake further cardiac investigation.

Comparison of Myocardial Layer-Specific Strain and Global Myocardial Work Efficiency During Treadmill Exercise Stress in Detecting Significant Coronary Artery Disease.

BackgroundMyocardial layer-specific strain can identify myocardial ischemia. Global myocardial work efficiency (GWE) based on non-invasive left ventricular (LV) pressure-strain loops is a novel parameter to determine LV function considering afterload. The study aimed to compare the diagnostic value of GWE and myocardial layer-specific strain during treadmill exercise stress testing to detect significant coronary artery disease (CAD) with normal baseline wall motion.MethodsEighty-nine patients who referred for coronary angiography due to suspected of CAD were included. Forty patients with severe coronary artery stenosis were diagnosed with significant CAD, and 49 were defined as non-significant CAD. Stress echocardiography was performed 24 h before angiography. Layer-specific longitudinal strains were assessed from the endocardium, mid-myocardium, and epicardium by 2D speckle-tracking echocardiography. Binary logistic regression analyses were performed to evaluate the association between significant CAD and echocardiographic parameters. A receiver operating characteristic curve was used to assess the capability of layer-specific strain and GWE to diagnose significant CAD.ResultsPatients with significant CAD had the worse function in all three myocardial layers at peak exercise compared with those with non-significant CAD when assessed with global longitudinal strain (GLS). At the peak exercise and recovery periods, GWE was lower in patients with significant CAD than in patients with non-significant CAD. In multivariable binary logistic regression analysis, peak endocardial GLS (OR: 1.35, p = 0.006) and peak GWE (OR: 0.76, p = 0.001) were associated with significant CAD. Receiver operating characteristic curves showed peak GWE to be superior to mid-myocardial, epicardial, and endocardial GLS in identifying significant CAD. Further, adding peak GWE to endocardial GLS could improve diagnostic capabilities.ConclusionsBoth GWE and endocardial GLS contribute to improving the diagnostic performance of exercise stress echocardiography. Furthermore, adding peak GWE to peak endocardial GLS provides incremental diagnostic value during a non-invasive screening of significant CAD before radioactive or invasive examinations.

Нарушения эндотелий-зависимой вазодилатации у больных с микрососудистой стенокардией

Background: disorders of both endothelium-dependent and endothelium-independent vasodilation play a role in the pathogenesis of microvascular angina (MVA), the contribution of which may be different. Aim: to study the processes of endothelium-dependent vasodilation (EDV) in patients with primary MVA. Patients and Methods: an open prospective study included 60 patients (mean age 57.3±6.4 years) with MVA, confirmed clinical picture (chest pain), coronary angiography data (the absence of coronary artery stenosis), positive stress test (pain syndrome and/or ST segment depression by ≥2 mm by treadmill exercise stress test), positron emission tomography (PET) myocardial perfusion imaging (MPI) with tests (cold pressor test and with adenosine). Patients with diseases that can lead to secondary microvascular dysfunction were not included in the study. To evaluate the processes of EDV, all patients underwent the following evaluations: peripheral arterial tonometry (PAT), assessment of circulating endothelial cells (CEC), high-sensitivity C-reactive protein (hsCRP), endothelin-1 (ET-1), total antioxidant status. Adding that, the results of a cold pressor test during PET were analyzed. Results: the majority of the examined patients were women — 81.7%. Most of the female patients included in the study (93.9%) were postmenopausal. In all patients with MVA, according to the data of PET MPI with cold pressor test, signs of EDV disorder were detected as a decrease in coronary blood flow through the three coronary arteries. During PET, the index of reactive hyperemia was reduced (&lt;1,67) in all examined patients and amounted to 1.43±0.15. According to the results of laboratory studies, there was an increase in the level of ET-1 and CEC — 3,335 [1,545; 3,952] fmol/L and 14±8 cells/3×105 leukocytes, respectively. The CRP level was 4,44 [1.02; 4.45] mg/L. The total antioxidant capacity was reduced in 53 (88%) patients, the average values of the indicator were 289,03±52,14 μmol/L. Conclusion: according to laboratory and instrumental studies, signs of endothelial dysfunction, namely disorders of EDV, were revealed in all examined patients with primary MVA. KEYWORDS: microvascular angina, peripheral arterial tonometry, endothelium-dependent vasodilation, positron emission tomography. FOR CITATION: Leonova I.A., Zakharova O.V., Boldueva S.A. Disorders of endothelium-dependent vasodilation in patients with microvascular angina. Russian Medical Inquiry. 2022;6(8):427–432 (in Russ.). DOI: 10.32364/2587-6821-2022-6-8-427-432.

Evaluation of Left Ventricular Systolic Function in Patients with Coronary Microvascular Dysfunction by Three-Dimensional Speckle-Tracking Imaging.

IntroductionThe objective of this study is to evaluate the left ventricular systolic function of patients with coronary microvascular dysfunction (CMD) using the three-dimensional speckle-tracking imaging (3D-STI) technique.MethodsFrom June 2018 to June 2019,72 subjects from Huzhou Central Hospital were enrolled, including 42 CMD in-patients with typical chest pain or chest tightness and positive treadmill exercise stress test, but without coronary stenosis on coronary angiography, (the CMD group) and another 30 healthy individuals who were undergoing physical examinations in an outpatient clinic (the control group). Using 3D-STI technique, the global longitudinal strain (GLS), global radial strain (GRS), global circumferential strain (GCS), global area strain (GAS), and left ventricle were measured.ResultsCompared with the control group, GLS and GAS were significantly reduced in the CMD group (P<0.05), while GRS and GCS were similar in both groups (P>0.05). Univariate logistic regression analysis showed that GLS and GAS were the influencing factors of CMD. For the diagnosis of CMD, the area under the receiver operating characteristic (ROC) curve of GLS was 0.883, and the area under the ROC curve of GAS was 0.875. GAS of -29.3% (log-rank test chi-square=34.245, P<0.001) was a strong predictor of major adverse cardiac events.Conclusion3D-STI technique has obvious advantages in the evaluation of the left ventricular systolic function for CMD patients. Moreover, 3D-STI parameters, especially GLS and GAS, can detect the early abnormal changes in the ischaemic myocardium. Being timelier and more sensitive than echocardiography, 3D-STI should be recommended for clinical application.

641 Left ventricular non-compaction as a distinct cardiomyopathy or a phenotypic feature: a case report

Abstract A 71-year-old male with no cardiovascular risk factors and a history of two uninvestigated episodes of loss of consciousness one year before, presented in our department to undergo a treadmill exercise stress test in relation to inverted T waves in V5-V6 on his basal ECG and frequent ventricular extrasystoles (PVCs). The stress test was positive for inducible ischemia, with a significant depression of the ST-segment in the lateral lead. A transthoracic echocardiography revealed normal thicknesses and volumes of the left ventricle (LV) with a dyskinesia of the lateral wall and a mildly reduced ejection fraction (EF) up to 46%. Epicardial surface was unremarkable. Next, a coronary angiography showed no critical obstruction in the epicardial coronary arteries. In order to further investigate the frequent PVCs and the reduction of the LV systolic function, a cardiac magnetic resonance (CMR) with paramagnetic contrast agent was performed. The images outlined the presence of non-compaction in the distal lateral wall and apex with a late gadolinium enhancement (LGE) in the epicardial portion of the lateral wall (Figure 1). Moreover, the CMR showed an adipose infiltration of the interventricular septum and thickened right ventricular trabeculae, suggesting an overlap with arrhythmogenic left ventricular dysplasia. During the subsequent follow-up, the patient was implanted with an implantable cardiac defibrillator (ICD), after two reported episodes of loss of consciousness and an electrophysiology study (EPS) resulting in the induction of a symptomatic ventricular tachycardia. Non-compaction cardiomyopathy is a rare and still relatively novel nosological entity, which can sometimes be observed in the same patient with other forms of cardiomyopathy. In the context of an unexplained reduction of LVEF and frequent PVCs, the accuracy of CMR in describing cardiac morphology and myocardial layer remains an indispensable tool to detect otherwise underdiagnosed potentially fatal cardiomyopathies.

Utility of Exercise Stress Testing in Pediatric Patients with T-Wave Inversions.

T-wave inversions (TWI) in inferolateral electrocardiogram (ECG) leads (II, III, aVF, V5-V6) are often suggestive of cardiac pathology in adult patients. They are a common reason of additional testing in pediatric patients. The goal of the study is to determine correlation of exercise stress test T-wave response with diagnosis of cardiac pathology. This is a retrospective review of pediatric patients < 21years with the finding of baseline TWI in inferior (II, III, avF) and/or lateral (V5-V6) leads on 12-lead ECG. All patients underwent treadmill exercise stress test (EST) and an echocardiogram within 1year of each other. Demographics, baseline ECG findings, echocardiogram results, and EST data were recorded. T-wave reversion was considered complete if T waves demonstrated normalization during exercise, partial if there was minimal improvement, and no response if there was no change or worsening of inversions. In our cohort of 72 patients with a mean age 14.6 (± 2.9) yearsand 61% males, 59 (82%) had a structurally normal heart. Thirteen patients had evidence of structural or functional heart disease. Of the 59 patients, 83% had either complete or partial T-wave response. Among the 13 patients with heart disease, two patients had genetic testing consistent with risk for hypertrophic cardiomyopathy and had complete and partial response on EST. Exercise stress testing for TWI in pediatric patients has low sensitivity and specificity for the diagnosis of cardiac disease and routine use in this patient population may not be indicated.

The prognostic role of heart rate recovery after exercise and metabolic syndrome in IgA nephropathy

BackgroundCardiovascular (CV) morbidity and mortality are higher in chronic kidney disease (CKD) than in the general population. Reduced heart rate recovery (HRR) is an independent risk factor for CV disease. The aim of the study was to determine the prognostic role of HRR in a homogenous group of CKD patients.MethodsOne hundred and twenty-five IgA nephropathy patients (82 male, 43 female, age 54.7 ± 13 years) with CKD stage 1–4 were investigated and followed for average 70 months. We performed a graded exercise treadmill stress test. HRR was derived from the difference of the peak heart rate and the heart rate at 1 min after exercise. Patients were divided into two groups by the mean HRR value (22.9 beats/min). The composite (CV and renal) endpoints included all-cause mortality and any CV event such as stroke, myocardial infarction, revascularisation (CV) and end-stage renal disease, renal replacement therapy (renal).ResultsPatients with reduced HRR (< 23 bpm) had significantly more end point events (22/62 patients vs. 9/53 patients, p = 0.013) compared to the higher HRR (≥23 bpm). Of the secondary the endpoints (CV or renal separately) rate of the renal endpoint was significantly higher in the lower HRR group (p = 0.029), while there was no significant difference in the CV endpoint between the two HRR groups (p = 0.285). Independent predictors of survival were eGFR and diabetes mellitus by using Cox regression analysis. Kaplan-Meier curves showed significant differences in metabolic syndrome and non-metabolic syndrome when examined at the combined endpoints (cardiovascular and renal) or at each endpoint separately. The primary endpoint rate was increased significantly with the increased number of metabolic syndrome component (Met.sy. comp. 0 vs. Met. sy. comp. 2+, primary endpoints, p = 0.012).ConclusionOur results showed that reduced HRR measured by treadmill exercise test has a predictive value for the prognosis of IgA nephropathy. The presence of metabolic syndrome may worsen the prognosis of IgA nephropathy.

Abstract 9049: Masking the Bruce Protocol: Surgical Masks Decrease Exercise Duration

Introduction: Exercise stress echocardiography is a critical tool in the workup and assessment of angina, dyspnea, and cardiac disease. Due to the ongoing COVID-19 pandemic, the American Society of Echocardiography recommends that all patients wear surgical facemasks during exercise stress testing. Hypothesis: We hypothesized that masks decrease test duration, increase likelihood of test stoppage due to dyspnea, and increase likelihood of abnormal test results. Methods: We performed a retrospective chart review of 565 treadmill stress echocardiograms utilizing Bruce protocol between April 2019-July 2019 (without mask) and April 2020-July 2020 (with mask). Chi square and T testing were used for statistical analysis, controlling for age and gender. Results: Unmasked patients had a greater mean exercise duration than masked patients (8:12 min vs 7:35 min, p=.02), and were less likely to have dyspnea during the test than masked patients (odds ratio 0.58 [95% CI 0.39, 0.83], p=.003). Unmasked patients were twice as likely to develop chest pain during the test than masked patients (odds ratio 2.0 [95% CI 1.26, 3.22], p=.003). Lastly, unmasked patients were less likely to have an abnormal test result than masked patients, though the difference was not significant (odds ratio 0.81 [95% CI 0.43, 1.51], p=0.50). Conclusions: Surgical mask use during treadmill exercise stress tests associated with a significant decrease in test duration, increased dyspnea during the test, and a non-significant increase in likelihood of abnormal test result. Given the critical importance of stress testing in ischemia evaluation, further exploration is warranted to determine whether mask use during stress tests affects downstream testing, diagnoses, and outcomes.

Effect of recreational exercise and fitness on left ventricular torsion and wall mechanics study (FIT-TWIST/Health)

Abstract Background Left ventricular (LV) remodeling is associated with elite athletics. This study aimed to assess the effects of recreational exercise on LV remodeling and mechanics in healthy adults. Methods A prospective cross-sectional study evaluated 38 healthy adult recreational exercise participants with a Bruce protocol treadmill exercise stress test, and 2D and speckle-tracking echocardiography. Fitness level was stratified by the achieved age- and sex-predicted metabolic equivalents (METS) as average/good (group A, N=20; METS=13.9) and high (group B, N=18; METS=18.2) groups. Results Mean age was 33 years, and 58% were female. Participants in Group B used more multi-modality (67 vs 20%; p=0.008) or running (50% vs 15%; p=0.04) exercise regimens, and had larger LV mass (66 vs 56 g/m2; p=0.05) and left atrial volume indices (28 vs 22 ml/m2; p=0.02), when compared with group A. However, all LV strain and torsion mechanics were similar between groups (Figure). Multivariate linear regression analysis revealed independent associations between global longitudinal strain (GLS) and transmitral E-wave (β=−0.57), maximum systolic blood pressure (β=0.32), and LV end-diastolic volume index (β=0.32) (model r=0.72; p&amp;lt;0.001). No correlation between METS achieved and LV parameters was observed. Conclusion Recreational exercise and fitness are associated with healthy LV geometry and mechanics in adults. Early diastolic LV filling, LV chamber size, and peak exercise blood pressure are correlated with GLS. Funding Acknowledgement Type of funding sources: Private grant(s) and/or Sponsorship. Main funding source(s): Florida Heart Research Foundation

Myocardial ischemia and left ventricular diastolic dysfunction in HIV infected patients and asymptomatic for coronary artery disease

Highly active antiretroviral therapy (HAART) allows chronicity of AIDS evolution, leading to association of other pathologies such as coronary artery disease (CAD). Myocardial ischemia (MI) and left ventricular diastolic dysfunction (LVDD) evaluation in HIV-infected patients may favor primary prevention of CAD. The study aimed to evaluate frequencies of MI and LVDD in the population living with the human immunodeficiency virus (PLHIV) and asymptomatic for CAD. We analyzed data from 110 HIV-infected patients who underwent clinical and laboratory evaluation, treadmill exercise stress test, and transthoracic echocardiogram, and compared it with 2,619 healthy individuals from the control group (non-HIV and non-CAD), selected from the database. HIV-infected patients presented lower average age (51.5 ± 7.7), systemic arterial hypertension (28.0%) and dyslipidemia frequencies (32.0%). On the other hand, their MI frequency was twice as high (14.7%); and diastolic dysfunction (DD) percentage was higher in ischemic patients (45.5%). In the HIV-infected group, MI frequency was 10.0%, while that of DD was 18.2%. MI was twice as frequent among HIV infected patients compared to uninfected, despite lower frequency of risk factors for CAD. Non-ischemic patients living with HIV had a frequency of DD more than twice compared to the control individuals.

Blood pressure response during treadmill exercise testing and the risk for future cardiovascular events and new-onset hypertension.

The physiologic response to exercise may provide valuable prognostic information. We investigated the association of blood pressure (BP) measurements during exercise stress testing (EST) with long-term risk of myocardial infarction, stroke or death (major adverse cardiovascular event, MACE), as well as the development of new-onset hypertension. A retrospective analysis of treadmill ESTs (years 2005-2019) performed by the Bruce protocol in patients aged 35-75 years without a history of cardiovascular disease (n = 14 792; 48% women). BP was documented at rest, submaximal exercise (Bruce stage-2), peak exercise and recovery (2 min). Association of SBP measures with study outcomes during median follow-up of 6.5 years was investigated. Highest vs. lowest SBP quartile at rest (≥140 vs. <120 mmHg), submaximal-exercise (≥170 vs. <130 mmHg), peak-exercise (≥180 vs. ≤145 mmHg) and recovery (≥160 vs. <130 mmHg) was associated with an increase in the adjusted hazard ratio and 95% confidence interval (CI) for MACE: 1.53 (1.23-1.88), 1.33 (1.01-1.76), 1.30 (1.05-1.61), 1.35 (1.09-1.68), respectively. The association between SBP at submaximal exercise and recovery with MACE displayed a J-shaped pattern. Among nonhypertensive patients (n = 8529), excessive SBP response to peak exercise (≥190 mmHg in women and ≥210 mmHg in men) was an independent predictor of hypertension [hazard ratio (95% CI)]: 1.87 (1.41-2.48), as were SBPs during submaximal exercise [>160 vs. ≤130 mmHg: 2.44 (1.97-3.03)] and recovery [≥140 vs. ≤120 mmHg: 1.65 (1.37-1.98)]. BP measurement during rest, exercise and recovery phases of EST provides incremental prognostic information regarding long-term risk for cardiovascular events and the probability for developing hypertension.

B-PO03-009 DUAL AV NODE PATHWAYS MASQUERADING AS SYMPTOMATIC ATRIOVENTRICULAR CONDUCTION DISEASE: THE IMPORTANCE OF TREADMILL STRESS TESTING IN ESTABLISHING SYMPTOM-ARRHYTHMIA CORRELATION

Markedly prolonged AV conduction intervals (PR intervals >300ms) may represent slow pathway conduction in patients with previously undiagnosed dual AV node physiology. Treadmill stress testing is a simple and effective way to distinguish between dual AV node physiology and true AV nodal disease in patients with exertional dyspnea. 61 yo female with no significant past medical history referred to EP clinic for dual chamber pacemaker implantation. The patient presented with exercise intolerance secondary to exertional dyspnea and AV nodal conduction block thought to be contributing to her symptoms. Baseline EKG showed normal sinus rhythm and markedly prolonged PR interval at 420 ms. All other studies, including echocardiogram and pertinent bloodwork, were within normal limits. The patient agreed to proceed with exercise treadmill stress testing in an attempt to correlate her symptoms with suspected arrhythmias (AV conduction block). N/A Treadmill stress testing was performed. The patient exercised for 7 min 29 sec in a standard Bruce protocol (9.2 METS). Test was terminated secondary to fatigue and dyspnea. She exhibited a normal chronotropic response (86% MPHR). No ST segment changes consistent with ischemia were observed. Importantly, review of EKGs performed during testing revealed abrupt shortening of the PR interval during exercise. This response to exercise was consistent mechanistically with the existence of dual AV node physiology, as well as preferential fast-pathway conduction and retrograde slow-pathway block during exertion. Identification of dual-AVN physiology excluded the need for pacemaker implantation. While a markedly elevated PR interval can cause exertional dyspnea secondary to dyssynchronous atrial systole or progression to AV conduction block (Mobitz Type I/II). Establishing a symptom-arrhythmia correlation is a crucial diagnostic step. As outlined above, treadmill testing identified dual AVN physiology, and revealed benign preferential slow pathway conduction at rest as the source of the prolonged PR interval. This test excluded AV nodal disease as the source of symptoms, and ensured that the patient did not undergo unnecessary pacemaker implantation.

The Identification and Impact of Abnormal Spirometry Patterns on Exercise Capacity in Pediatric Patients with Fontan Palliation.

Reduced exercise capacity and restrictive lung physiology are common in patients after Fontan palliation (FP). However, there is paucity of data regarding the association between specific spirometry patterns and key exercise parameters in this population. This is a single-center, cross-sectional, study correlating pulmonary function and exercise parameters in children with FP. Patients who were ≤ 18years of age and underwent a comprehensive cardiopulmonary treadmill exercise stress test (CPT) and spirometry at the same time, were included. Patients were categorized as (i) normal or (ii) abnormal based on the results of spirometry. The abnormal group was subdivided into (a) restrictive, (b) obstructive, and (c) mixed patterns. Demographic and key exercise parameters were compared between groups. Our study included 82 patients who underwent CPT at 13.6 (IQR, 11.3-15.4) years of age. A reduced exercise capacity (%VO2 ≤ 85%) was noted in the majority (n = 50, 61%). Spirometry was abnormal in 47 (57%) patients [restrictive (n = 25, 30%), obstructive (n = 12, 15%), and mixed (n = 10, 12%)]. The abnormal spirometry group had significant lower %VO2 (77% vs. 92%, p = 0.01) and METS (8.4 vs. 9.6, p = 0.02). Subgroup analysis revealed that obstructive (p = 0.04) and mixed (p = 0.02) patterns were associated with a significant decrease in % VO2. Majority of the children demonstrated an abnormal spirometry pattern post-FP. Abnormal pulmonary function was associated with the reduced exercise capacity. Identification and treatment of the abnormal lung function may improve the exercise capacity in these patients and improve the morbidity.