Assessing post-exercise respiratory gas kinetics in clinical sample - a pilot study

2021 ◽  
Vol 28 (Supplement_1) ◽  
Author(s):  
A Patti ◽  
Y Blumberg ◽  
KJ Moneghetti ◽  
D Neunhaeuserer ◽  
F Haddad ◽  
...  
Keyword(s):  
Heart Failure ◽  
Healthy Subjects ◽  
Cardiopulmonary Exercise Testing ◽  
University Hospital ◽  
Exercise Intolerance ◽  
Early Recovery ◽  
Post Exercise ◽  
Peak Vo2 ◽  
Significant Difference ◽  
Respiratory Gases

Abstract Funding Acknowledgements Type of funding sources: None. Background Cardiopulmonary exercise testing (CPX) is established in the evaluation of patients with cardiac and pulmonary diseases, and its clinical utility seems to be expanding.  Currently the most important diagnostic and prognostic ventilatory metrics of CPX rely on the exercise phase. Nevertheless, a consistent body of evidence suggests that important information can be derived from the recovery phase, especially in the first few minutes after exercise. In this context, patients with heart failure (HF) demonstrate a slower recovery of the oxygen consumption (VO2) compared with healthy individuals. Purpose: To comprehensively investigate the behavior of respiratory gases during recovery from CPX in a diverse cohort of HF patients. Methods: All individuals who performed CPX at the department of cardiology of Stanford University Hospital were eligible for the study. Patients were included in the experimental group if they (i) were recorded for five minutes after the exercise phase of CPX and (ii) had documented heart failure. They were excluded if they had other clinical diagnoses which may be responsible for exercise intolerance or symptoms or were unable to give informed consent. Healthy controls were recruited from the local community and were included if they did not have documented or suspected disease. Respiratory gases were collected on a breath-by-breath basis and analysed after applying a 30 second rolling average filter. Metrics were analyzed as absolute values, percentage change from peak and the half-time of recovery (T ½; i.e. the duration until a metric had returned to ½ of its value at peak). Data was analyzed over time within patients and averages between groups using parametric statistical methods. In accordance with previous studies, the amount of change in a metric after exercise is presented as the "magnitude" of overshoot. Results: 32 patients with HF (11 Female, 47 ± 13 yrs) and 30 healthy subjects (14 Female, 43 ± 12 yrs) were included. A comparison of ventilatory metrics during recovery between HF and controls is depicted in Figure 1. Peak VO2 was 1135 ± 419 mL/min (13.5 ± 3.8 mL/Kg/min) vs 2408 ± 787 mL/min (32.5 ± 9.0 mL/Kg/min); P <0.01. A significant difference between patients with HF and healthy subjects was found in T ½ of VO2 (111.3 ± 51.0s vs 58.0 ± 13.2s, p < 0.01) and VCO2 (132.0 ± 38.8s vs 74.3 ± 21.1s, p < 0.01). The magnitude of the overshoot was also found to be significantly reduced in patients with HF for VE/VO2 (41.9 ± 29.1% vs 62.1 ± 17.7%, P < 0.01), RQ (25.0 ± 13.6% vs 38.7 ± 15.1%, p < 0.01) and PETO2 (7.2 ± 3.3% vs 10.1 ± 4.6%, p < 0.01). Finally, the magnitude of the RQ overshoot showed a moderate correlation with peak VO2 (ϱ=0.58, p < 0.01). Conclusions: We observed that ventilatory kinetics measured in early recovery after CPX differ significantly between healthy subjects and patients with HF. The assessment of post exercise respiratory gases in a clinical setting may add to the prognostic and diagnostic value of CPX in heart failure. Abstract Figure.

The importance of first and second ventilatory thresholds to define aerobic exercise intensity in cardiac patients and in healthy subjects: what is essential can be visible to the eyes

2021 ◽  
Vol 28 (Supplement_1) ◽  
Author(s):  
F Anselmi ◽  
L Cavigli ◽  
A Pagliaro ◽  
S Valente ◽  
F Valentini ◽  
...  
Keyword(s):  
Exercise Intensity ◽  
Healthy Subjects ◽  
Ventilatory Threshold ◽  
Cardiopulmonary Exercise Testing ◽  
Cardiac Patients ◽  
Funding Sources ◽  
Peak Vo2 ◽  
Definition Of ◽  
Very High ◽  
Sedentary Subjects

Abstract Funding Acknowledgements Type of funding sources: None. Background. Although structured exercise training is strongly recommended in cardiac patients, uncertainties exist about the methods for determining exercise intensity (EI) and their correspondence with effective EI obtained by ventilatory thresholds. We aimed to determine the first (VT1) and second ventilatory threshold (VT2) in cardiac patients, sedentary subjects and athletes comparing VT1 and VT2 with EI defined by recommendations. Methods. We prospectively enrolled 350 subjects (mean age: 50.7 ± 12.9 years; 167 cardiac patients, 150 healthy sedentary subjects, 33 competitive endurance athletes). Each subject underwent ECG, echocardiography, and cardiopulmonary exercise testing. The percentages of peak VO2, peak heart rate (HR), and HR reserve were obtained at VT1 and VT2, and compared with EI definition proposed by the recommendations. Results. VO2 at VT1 corresponded to high rather than moderate EI in 67.1% and in 79.6% of cardiac patients, applying the definition of moderate exercise by the previous recommendations and the 2020 guidelines, respectively. Most of cardiac patients had VO2 values at VT2 corresponding to very-high rather than high EI (59.9% and 50.3%, by previous recommendations and 2020 guidelines, respectively). A better correspondence between ventilatory-thresholds and recommended EI domains was observed in healthy subjects and in athletes (90% and 93.9%, respectively). Conclusions. EI definition based on percentages of peak HR and peak VO2 may misclassify the effective EI and the discrepancy between the individually determined and the recommended EI is particularly relevant in cardiac patients. A ventilatory threshold-based rather than a range-based approach is advisable in order to define an appropriate level of EI. Abstract Figure.

Comparison of Bone-Conducted Vibration for Eliciting Ocular Vestibular-Evoked Myogenic Potentials

2011 ◽  
Vol 146 (2) ◽  
pp. 289-294 ◽  
Author(s):  
Chia-Chen Tseng ◽  
Shou-Jen Wang ◽  
Yi-Ho Young
Keyword(s):  
Prospective Study ◽  
Study Design ◽  
Healthy Subjects ◽  
University Hospital ◽  
Vestibular Evoked Myogenic Potentials ◽  
Ménière’S Disease ◽  
Asymmetry Ratio ◽  
Significant Difference ◽  
The Asymmetry ◽  
The Right

Objective. This study compared bone-conducted vibration (BCV) stimuli at forehead (Fz) and mastoid sites for eliciting ocular vestibular-evoked myogenic potentials (oVEMPs). Study Design. Prospective study. Setting. University hospital. Methods. Twenty healthy subjects underwent oVEMP testing via BCV stimuli at Fz and mastoid sites. Another 50 patients with unilateral Meniere’s disease also underwent oVEMP testing. Results. All healthy subjects showed clear oVEMPs via BCV stimulation regardless of the tapping sites. The right oVEMPs stimulated by tapping at the right mastoid had earlier nI and pI latencies and a larger nI-pI amplitude compared with those stimulated by tapping at the Fz and left mastoid. Similar trends were also observed in left oVEMPs. However, the asymmetry ratio did not differ significantly between the ipsilateral mastoid and Fz sites. Clinically, tapping at the Fz revealed absent oVEMPs in 28% of Meniere’s ears, which decreased to 16% when tapping at the ipsilesional (hydropic) mastoid site, exhibiting a significant difference. Conclusion. Tapping at the ipsilateral mastoid site elicits earlier oVEMP latencies and larger oVEMP amplitudes when compared with tapping at the Fz site. Thus, tapping at the Fz site is suggested to screen for the otolithic function, whereas tapping at the ipsilesional mastoid site is suitable for evaluating residual otolithic function.

scholarly journals Cardiopulmonary Exercise Test in heart failure: A Sine qua non

2020 ◽  
Vol 9 (2) ◽  
pp. 1-8 ◽  
Author(s):  
Stefanos Sakellaropoulos ◽  
Dimitra Lekaditi ◽  
Stefano Svab
Keyword(s):  
Heart Failure ◽  
Exercise Test ◽  
Exercise Physiology ◽  
Cardiopulmonary Exercise Testing ◽  
Critical Evaluation ◽  
Research Area ◽  
Cardiopulmonary Exercise Test ◽  
Exercise Intolerance ◽  
Reduced Ejection Fraction ◽  
Cardiopulmonary Exercise

A robust literature, over the last years, supports the indication of cardiopulmonary exercise testing (CPET) in patients with cardiovascular diseases. Understanding exercise physiology is a crucial component of the critical evaluation of exercise intolerance. Shortness of breath and exercise limitation is often treated with an improper focus, partly because the pathophysiology is not well understood in the frame of the diagnostic spectrum of each subspecialty. A vital field and research area have been cardiopulmonary exercise test in heart failure with preserved/reduced ejection fraction, evaluation of heart failure patients as candidates for LVAD-Implantation, as well as for LVAD-Explantation and ultimately for heart transplantation. All the CPET variables provide synergistic prognostic discrimination. However, Peak VO2 serves as the most critical parameter for risk stratification and prediction of survival rate.

Chronic heart failure diagnosis: HFpEF

ESC CardioMed ◽  
2018 ◽  
pp. 1762-1768
Author(s):  
Daniel N. Silverman ◽  
Sanjiv J. Shah
Keyword(s):  
Heart Failure ◽  
Ejection Fraction ◽  
Cardiopulmonary Exercise Testing ◽  
Clinical History ◽  
Right Heart Catheterization ◽  
Clinical Syndrome ◽  
Exercise Intolerance ◽  
Heart Catheterization ◽  
Reduced Ejection Fraction ◽  
Treatment Measures

Heart failure (HF) with preserved ejection fraction (HFpEF) is a very common clinical syndrome that is often misdiagnosed or overlooked due to diagnostic challenges with the lack of a specific imaging test or biomarker to make a conclusive diagnosis. Unlike HF with reduced ejection fraction, neither a reduced ejection fraction nor a dilated left ventricle is available to easily make the diagnosis of HFpEF. Furthermore, while echocardiographic evidence of diastolic dysfunction is common in patients with HFpEF, it is not a universal phenomenon. Even natriuretic peptides, which are generally thought to have good negative predictive value for the diagnosis of HF, are frequently not elevated in HFpEF patients. Finally, the cardinal symptoms of HFpEF such as dyspnoea and exercise intolerance are non-specific and may be due to many of the co-morbidities present in patients in whom the HFpEF diagnosis is entertained. This chapter presents a step-wise approach utilizing a careful clinical history, physical examination, natriuretic peptide testing, and echocardiography, which can reliably provide appropriate information to rule in or rule out the HFpEF diagnosis in the majority of patients. If there is still a question about the diagnosis, or if initial general treatment measures for the HF syndrome do not result in clinical improvement, additional testing such as right heart catheterization or cardiopulmonary exercise testing can be performed to further confirm the diagnosis. With a systematic approach to the patient with dyspnoea, the accurate diagnosis of HFpEF can be made reliably so that these high-risk patients can be appropriately treated.

Prognostic value of mean platelet volume on tinnitus

2015 ◽  
Vol 130 (2) ◽  
pp. 162-165 ◽  
Author(s):  
O Kemal ◽  
T Müderris ◽  
F Başar ◽  
G Kutlar ◽  
F Gül
Keyword(s):  
Mean Platelet Volume ◽  
Healthy Subjects ◽  
Clinical Findings ◽  
University Hospital ◽  
Control Group ◽  
Study Group ◽  
Pathophysiological Mechanism ◽  
Platelet Volume ◽  
Significant Difference ◽  
Healthy Control

AbstractObjective:This study aimed to determine whether there was any relationship between tinnitus and mean platelet volume.Methods:This retrospective study was conducted between January 2013 and January 2014 in Ankara Atatürk Hospital and Ondokuz Mayıs University Hospital, Turkey, on a study group of 86 patients with tinnitus and a control group of 84 healthy subjects. Mean platelet volume was recorded and comparisons were made between the two groups.Results:Mean (± standard deviation) platelet volume was 7.67 ± 0.83 μm3 in the study group and 7.28 ± 0.56 μm3 in the control group. There was a statistically significant difference in mean platelet volume between the tinnitus patients and the healthy subjects (p < 0.05).Conclusion:The clinical findings indicated that tinnitus patients had a higher mean platelet volume than the healthy control subjects; however, the pathophysiological mechanism remains unclear.

scholarly journals Cardiopulmonary Exercise Testing in Patients with Chronic Heart Failure: Prognostic Comparison from Peak VO2 and VE/VCO2 Slope

2010 ◽  
Vol 4 (1) ◽  
pp. 127-134 ◽  
Author(s):  
Filippo Maria Sarullo ◽  
Giovanni Fazio ◽  
Ignazio Brusca ◽  
Sergio Fasullo ◽  
Salvatore Paterna ◽  
...  
Keyword(s):  
Heart Failure ◽  
Chronic Heart Failure ◽  
Risk Stratification ◽  
Operating Characteristic ◽  
Characteristic Curve ◽  
Cardiopulmonary Exercise Testing ◽  
Cardiopulmonary Exercise ◽  
Peak Vo2 ◽  
Operating Characteristic Curve ◽  
Related Mortality

Background: Cardiopulmonary exercise testing with ventilatory expired gas analysis (CPET) has proven to be a valuable tool for assessing patients with chronic heart failure (CHF). The maximal oxygen uptake (peak V02) is used in risk stratification of patients with CHF. The minute ventilation-carbon dioxide production relationship (VE/VCO2 slope) has recently demonstrated prognostic significance in patients with CHF. Methods: Between January 2006 and December 2007 we performed CPET in 184 pts (146 M, 38 F, mean age 59.8 ± 12.9 years), with stable CHF (96 coronary artery disease, 88 dilated cardiomyopathy), in NYHA functional class II (n.107) - III (n.77), with left ventricular ejection fraction (LVEF) ≤ 45%,. The ability of peak VO2 and VE/VCO2 slope to predict cardiac related mortality and cardiac related hospitalization within 12 months after evaluation was examined. Results: Peak VO2 and VE/VCO2 slope were demonstrated with univariate Cox regression analysis both to be significant predictor of cardiac-related mortality and hospitalization (p < 0.0001, respectively). Non survivors had a lower peak VO2 (10.49 ± 1.70 ml/kg/min vs. 14.41 ± 3.02 ml/kg/min, p < 0.0001), and steeper Ve/VCO2 slope (41.80 ± 8.07 vs. 29.84 ± 6.47, p < 0.0001) than survivors. Multivariate survival analysis revealed that VE/VCO2 slope added additional value to VO2 peak as an independent prognostic factor (χ2: 56.48, relative risk: 1.08, 95% CI: 1.03 – 1.13, p = 0.001). The results from Kaplan-Meier analysis revealed a 1-year cardiac-related mortality of 75% in patients with VE/VCO2 slope ≥ 35.6 and 25% in those with VE/VCO2 slope < 35.6 (log rank χ2: 67.03, p < 0.0001) and 66% in patients with peak VO2 ≤ 12.2 ml/kg/min and 34% in those with peak VO2 > 12.2 ml/kg/min (log rank χ2: 50.98, p < 0.0001). One-year cardiac-related hospitalization was 77% in patients with VE/VCO2 slope ≥ 32.5 and 23% in those with VE/VCO2 slope < 32.5 (log rank χ2: 133.80, p < 0.0001) and 63% in patients with peak VO2 ≤ 12.3 ml/kg/min and 37% in those with peak VO2 > 12.3 ml/kg/min (log rank χ2: 72.86, p < 0.0001). The VE/VCO2 slope was demonstrated with receiver operating characteristic curve analysis to be equivalent to peak VO2 in predicting cardiac-related mortality (0.89 vs. 0.89). Although area under the receiver operating characteristic curve for the VE/VCO2 slope was greater than peak VO2 in predicting cardiac-related hospitalization (0.88 vs 0.82), the difference was no statistically significant (p = 0.13). Conclusion: These results add to the present body of knowledge supporting the use of CPET in CHF patients. The VE/VCO2 slope, as an index of ventilatory response to exercise, is an excellent prognostic parameter and improves the risk stratification of CHF patients. It is easier to obtain than parameters of maximal exercise capacity and is of equivalent prognostic importance than peak VO2.

Abstract 16775: Body Mass Index Predicts Exercise Capacity in Patients With Hypertrophic Cardiomyopathy

Circulation ◽  
2014 ◽  
Vol 130 (suppl_2) ◽  
Author(s):  
Caroline A Ball ◽  
Carolyn M Larsen ◽  
Virginia Hebl ◽  
Jeffrey B Geske ◽  
Kevin C Ong ◽  
...  
Keyword(s):  
Body Mass Index ◽  
Hypertrophic Cardiomyopathy ◽  
Body Mass ◽  
Exercise Testing ◽  
Cardiopulmonary Exercise Testing ◽  
Systolic Pressure ◽  
Left Ventricular ◽  
Normal Weight ◽  
Peak Vo2 ◽  
Significant Difference

Introduction: Impaired peak VO2 and obesity are known predictors of morbidity and mortality in Hypertrophic Cardiomyopathy (HCM). The purpose of this study is to determine the degree of exercise impairment due to excess weight in patients with HCM. Methods: Adult HCM patients who underwent cardiopulmonary treadmill testing at our tertiary referral center from 2006 - 2012 and had consented to research participation were identified retrospectively. Percent predicted peak VO2 was calculated by the Astrand formula for men and the Jones formula for women which adjust for age and gender. Baseline echocardiographic features obtained within 1 week of exercise testing and % predicted peak VO2 were compared among four groups of patients stratified by body mass index (BMI). Results: 510 patients were identified, with a mean age at diagnosis of 44.3 ± 16.1 years, 186 (36.5%) female. Mean BMI at the time of cardiopulmonary exercise testing was 29.7 ± 5.3 and 227 (44.6%) patients had a BMI ≥ 30. Overweight and obese patients were older and were more likely to be male than their normal weight peers. However, there was no significant difference in ejection fraction (EF), resting left ventricular outflow tract gradient, right ventricular systolic pressure (RVSP), or septal thickness among the groups. HCM patients show impaired peak VO2 across all BMI groups. While peak VO2 increased progressively across BMI groups consistent with greater O2 demand generated by higher body weight, the adjusted peak VO2 in mL/kg/min fell progressively, indicating progressively greater performance impairment with increasing BMI despite similar degrees of cardiac impairment (p <0.0001) (Table 1). Conclusion: Increased BMI is associated with reduced exercise performance in a graded manner in HCM patients independent of cardiac impairment identified on echocardiography.

P1647Prognostic significance of circulating leukocyte subtype counts in patients with chronic heart failure

2019 ◽  
Vol 40 (Supplement_1) ◽  
Author(s):  
M Takae ◽  
E Yamamoto ◽  
F Oike ◽  
T Nishihara ◽  
K Fujisue ◽  
...  
Keyword(s):  
Heart Failure ◽  
Cardiovascular Events ◽  
Hazard Analysis ◽  
Left Ventricular ◽  
University Hospital ◽  
Left Ventricular Ejection ◽  
Monocyte Count ◽  
Ventricular Ejection Fraction ◽  
Kaplan Meier ◽  
Significant Difference

Abstract Background Inflammation, characterized by early leukocyte recruitment, is known to be associated with vascular endothelial dysfunction and atherosclerosis. Previous studies have reported that an increased leukocyte count is a risk factor for the progression of atherosclerosis in cardiovascular diseases, and we previously reported that a high monocyte count was an independent and incremental of cardiovascular events in patients with coronary artery disease. Furthermore, previous study also reported that inflammation play a role in the pathophysiology of heart failure (HF), but few studies have evaluated the prognostic role of monocyte in patients with HF. Purpose To elucidate the prognostic value of monocyte in HF, we investigated the association of monocyte counts in patients with HF with their future cardiovascular events, and compared them among new categories of HF in this study. Methods Consecutive HF patients referred for hospitalization at Kumamoto University Hospital between 2006 and 2015 were registered. Finally, a total of 678 HF patients were enrolled in the study, and were followed prospectively until 2016 or until the occurrence of cardiovascular events. We defined high monocyte group as monocyte counts ≥360/mm3 according to previous clinical reports. We further divided HF patients into three types according to left ventricular ejection fraction (LVEF) (HF with reduced LVEF (HFrEF), HF with mid-range LVEF (HFmrEF), and HF with preserved LVEF (HFpEF)). Results In this study, HFrEF was 82 patients, HFmrEF was 118 patients and HFpEF was 478 patients, respectively. The average of total monocyte counts were 397±136 in HFrEF and 375±172 in HFmrEF, and 341±138 in HFpEF patients. Kaplan-Meier analysis revealed that both HFrEF and HFmrEF patients with high monocyte group (≥360 /mm3) had a significant higher risk of HF-related events (P=0.03 and P=0.02, respectively) but not of total cardiovascular events compared with those with low monocyte groups (<360/mm3) (P=0.001). By contrast, high and low monocyte groups in HFpEF patients had no significant difference in both total cardiovascular and HF-related events. Multivariate Cox hazard analysis identified a high monocyte count as an independent and significant predictor of future HF-related events in HFrEF and HFmrEF patients (hazard ratio: 3.02, 95% confidence interval: 1.20–7.59, p=0.018). Next, by whether they had ischemic heart disease (IHD), we divided HFrEF and HFmrEF patients into two groups. Non-ischemic HF group with high monocyte counts had a significant higher risk of HF-related events compared to those with low monocyte counts (P=0.014). By contrast, there was no statistically significant difference of the occurrences of future HF-related events between in ischemic HF group with high and low monocyte counts. Conclusion A high monocyte count was an independent and incremental predictor of HF-related events in HFrEF and HFmrEF especially with IHD, but not in HFpEF patients.

Frequency domain characteristics of muscle sympathetic nerve activity in heart failure and healthy humans

1997 ◽  
Vol 273 (1) ◽  
pp. R205-R212 ◽  
Author(s):  
S. Ando ◽  
H. R. Dajani ◽  
J. S. Floras
Keyword(s):  
Heart Failure ◽  
Frequency Domain ◽  
Sympathetic Nerve ◽  
Healthy Subjects ◽  
Sympathetic Nerve Activity ◽  
Muscle Sympathetic Nerve Activity ◽  
Total Power ◽  
Breathing Frequency ◽  
Nerve Activity ◽  
Significant Difference

The purpose of this study was to characterize oscillations in muscle sympathetic nerve activity (MSNA) in the frequency domain in healthy subjects and patients with congestive heart failure (CHF) and to relate these to blood pressure (BP), heart rate (HR), and breathing frequency. MSNA burst frequency was significantly greater in CHF [52 +/- 21 (n = 12) vs. 35 +/- 11 (n = 19) bursts/min, P < 0.05], whereas breathing frequency and HR were similar. There was no significant difference between CHF and healthy subjects in total power, harmonic power, and nonharmonic power in the MSNA spectrum from 0 to 0.5 Hz, but low frequency power (LF, 0.05-0.15 Hz, P < 0.05) was reduced in heart failure patients. There was less coherence between BP and MSNA in the LF range, but similar spectral power in both groups in the very LF (VLF, 0-0.05 Hz) and high frequency (0.15-0.5 Hz) ranges. The transfer of MSNA oscillations into BP in the VLF (P < 0.05) and LF (P < 0.02) ranges was significantly lower in CHF, but gains in the transfer function and in the coherence between BP and MSNA and in the coherence between respiration and MSNA were similar in the two groups. These observations indicate that modulation of MSNA by the arterial baroreflex and respiration is preserved in CHF. The loss of LF power in the MSNA signal may be due to impaired neuroeffector transduction. The higher sympathetic nerve firing rate in CHF would therefore appear to be caused by factors other than the loss of regulation by these two inhibitory influences.

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