Author Archives: Paul Older

Exercise performance and symptoms in lowlanders with COPD ascending to moderate altitude: randomized trial.

Furian M; Flueck D; Latshang TD; Scheiwiller PM; Segitz SD; Mueller-Mottet S; Murer C; Steiner A; Ulrich S; Rothe T; Kohler M; Bloch KE;

International Journal Of Chronic Obstructive Pulmonary Disease [Int J Chron Obstruct Pulmon Dis] 2018 Oct 26; Vol. 13, pp. 3529-3538. Date of Electronic Publication: 20181026 (Print Publication: 2018).

Objective: To evaluate the effects of altitude travel on exercise performance and symptoms in lowlanders with COPD.
Design: Randomized crossover trial.
Setting: University Hospital Zurich (490 m), research facility in mountain villages, Davos Clavadel (1,650 m) and Davos Jakobshorn (2,590 m).
Participants: Forty COPD patients, Global Initiative for Obstructive Lung Disease (GOLD) grade 2-3, living below 800 m, median (quartiles) age 67 y (60; 69), forced expiratory volume in 1 second 57% predicted (49; 70).
Intervention: Two-day sojourns at 490 m, 1,650 m, and 2,590 m in randomized order.
Outcome measures: Six-minute walk distance (6MWD), cardiopulmonary exercise tests, symptoms, and other health effects.
Results: At 490 m, days 1 and 2, median (quartiles) 6MWD were 558 m (477; 587) and 577 m (531; 629). At 2,590 m, days 1 and 2, mean changes in 6MWD from corresponding day at 490 m were -41 m (95% CI -51 to -31) and -40 m (-53 to -27), n=40, P<0.05, both changes. At 1,650 m, day 1, 6MWD had changed by -22 m (-32 to -13), maximal oxygen uptake during bicycle exercise by -7% (-13 to 0) vs 490 m, P<0.05, both changes. At 490 m, 1,650 m, and 2,590 m, day 1, resting PaO2 were 9.0 (8.4; 9.4), 8.1 (7.5; 8.6), and 6.8 (6.3; 7.4) kPa, respectively, P<0.05 higher altitudes vs 490 m. While staying at higher altitudes, nine patients (24%) experienced symptoms or adverse health effects requiring oxygen therapy or relocation to lower altitude.
Conclusion: During sojourns at 1,650 m and 2,590 m, lowlanders with moderate to severe COPD experienced a mild reduction in exercise performance and nearly one quarter required oxygen therapy or descent to lower altitude because of adverse health effects. The findings may help to counsel COPD patients planning altitude travel.

Echo-derived peak cardiac power output-to-left ventricular mass with cardiopulmonary exercise testing predicts outcome in patients with heart failure and depressed systolic function.

Pugliese NR; Fabiani I; Mandoli GE; Guarini G; Galeotti GG; Miccoli M; Lombardo A; Simioniuc A; Bigalli G;
Pedrinelli R; Cardiac, Dini FL;

European Heart Journal Cardiovascular Imaging [Eur Heart J Cardiovasc Imaging] 2018 Nov 23. Date of Electronic Publication: 2018 Nov 23.

Aims: Peak cardiac power output-to-mass (CPOM) represents a measure of the rate at which cardiac work is delivered respect to the potential energy stored in left ventricular (LV) mass. We studied the value of CPOM and cardiopulmonary exercise test (CPET) in risk stratification of patients with heart failure (HF).
Materials and results: We studied 159 patients with chronic HF (mean rest LV ejection fraction 30%) undergoing CPET and exercise stress echocardiography. CPOM was calculated as the product of a constant (K = 2.22 × 10-1) with cardiac output (CO) and the mean blood pressure (MBP), divided by LV mass (M), and expressed in the unit of W/100 g: CPOM = [K × CO (L/min) × MBP (mmHg)]/LVM(g). Patients were followed-up for the primary endpoint, including all-cause death, ventricular assist device implantation, and heart transplantation, and the secondary endpoint that comprised hospitalization for HF. In multivariate Cox regression analyses, peak CPOM was selected as the most powerful independent predictor of both primary and secondary endpoint [hazard ratio (HR) 0.004, 95% confidence interval (CI) 0.004-0.3; P = 0.002 and HR 0.09, 95% CI 0.02-0.55; P = 0.009]. Sixty-month survival free from the combined endpoint was 85% in those exhibiting oxygen consumption (VO2) > 14 mL/min/kg and peak CPOM > 0.6 W/100 g. Peak VO2 ≤ 14 mL/min/kg provided incremental prognostic value over demographic and clinical variables, brain natriuretic peptide, and resting echocardiographic parameters (χ2 from 58 to 64; P = 0.04), that was further increased by peak CPOM ≤ 0.6 W/100 g (χ2 77; P < 0.001).
Conclusion: Peak CPOM and peak VO2 showed independent and incremental prognostic values in patients with chronic HF.

The Intra-rater and Inter-rater Reliability of measures derived from Cardiopulmonary Exercise Testing (CPET) in patients with Abdominal Aortic Aneurysms (AAA).

Harwood AE; Totty J; Wallace T; Smith GE; Carradice D; Carroll S; Chetter IC;

Annals Of Vascular Surgery [Ann Vasc Surg] 2018 Nov 23. Date of Electronic Publication: 2018 Nov 23.

Introduction: Patients with abdominal aortic aneurysms (AAA) often have low exercise tolerance due to comorbidities and advance age. Cardiopulmonary exercise testing (CPET) is predictive of post-operative morbidity and mortality in patients with AAA. We aimed to assess the intra- and inter-rater reliability of both treadmill and cycle ergometer based CPET variables.
Methods: Patients with a AAA (>3.5cm) were randomised to treadmill or bike CPET. Participants were asked to perform two separate CPET tests seven days apart after a familiarisation protocol. All CPETs were carried out using a ramp cycle or modified Bruce treadmill protocol with breath-by-breath gas analysis.
Results: Twenty-two male and 2 female patients, aged 73.6 ± 6.0, completed the study. Intra-rater analysis (intraclass correlation coefficients) demonstrated high reliability on both the treadmill and bike for VAT (r = 0.834 and r = 0.975, respectively). All other CPET variables demonstrated high intra-rater reliability on both modalities bar the highest point for VE/VO2 on the treadmill (substantial agreement r = 0.755). Further, inter-rater reliability demonstrated high agreement for VAT on both the treadmill and cycle (r = 0.983 and 0.905, respectively). All other CPET variables demonstrated high intra-rater reliability on both modalities, with the exception of VO2PEAK on the cycle ergometer (fair agreement r = 0.400).
Discussion: CPET in AAA patients is reliable on short-term repeat testing patients and between CPET test reviewers for common testing modalities/protocols. These findings provide further support for the use of CPET, especially treadmill walking, as a clinical measure of peri-operative cardiorespiratory fitness in patients with AAA.

 

Peak Blood Pressure Responses During Maximum Cardiopulmonary Exercise Testing: Reference Standards From FRIEND (Fitness Registry and the Importance of Exercise: A National Database).

Sabbahi A, Arena R, Kaminsky LA, Myers J, Phillips SA

Hypertension. 2018 Feb;71(2):229-236. doi: 10.1161/HYPERTENSIONAHA.117.10116.
Epub 2017 Dec 18.

The objective of this study is to expand on previous efforts in establishing
normative standards of exercising blood pressure (BP) at maximal physical
exertion derived from treadmill cardiopulmonary exercise testing in the United
States. Four experienced laboratories in the United States with established
quality control procedures contributed data from September 1, 1986, to February
1, 2015. A total of 2917 maximal (peak respiratory exchange ratio ≥1.00)
treadmill cardiopulmonary exercise testing responses from apparently healthy men
and women (aged 20-79 years) without cardiovascular disease were submitted to
FRIEND (Fitness Registry and the Importance of Exercise: A National Database).
Percentiles of maximal systolic and diastolic BP were determined for each decade.
Our results show a continued increase in peak systolic BP with age in both men
and women to the sixth decade, followed by a plateau between the sixth and
seventh decades. However, the trajectory of peak diastolic BP with age is
different between men and women. Men showed an increase in peak systolic BP until
the fifth decade, which plateaued by the seventh decade. In contrast, women
showed a continued increase in peak diastolic BP across each decade. Existing
reference data for exercising BP have not been updated for >20 years. Normative
peak exercising BP values from FRIEND can be used to provide a more current
representation of maximal BP during exercise testing in the US population.

Using predicted 30 day mortality to plan postoperative colorectal surgery care: a cohort study.

Swart M, Carlisle JB, Goddard J

Br J Anaesth. 2017 Jan;118(1):100-104. doi: 10.1093/bja/aew402.

BACKGROUND: Preoperative identification of high-risk surgical patients might help
to reduce postoperative morbidity and mortality. Using a patient’s predicted
30 day mortality to plan postoperative high-dependency unit (HDU) care after
elective colorectal surgery might be associated with reduced postoperative
morbidity.
METHODS: The 30 day postoperative mortality was predicted for 504 elective
colorectal surgical patients in a preoperative clinic. The prediction was used to
determine postoperative surgical ward or HDU care. Those with a predicted 30 day
mortality of 1-3% mortality, and thus deemed at intermediate risk, had either
planned HDU care (n=68) or planned ward care (n=139). The main outcome measures
were emergency laparotomy and unplanned critical care admission.
RESULTS: There were more emergency laparotomies and unplanned critical care
admissions in patients with a predicted 30 day mortality of 1-3% who went to an
HDU after surgery compared with patients who went to a ward: 0 vs 14 (10%),
P=0.0056 and 0 vs 22 (16%), P=0.0002, respectively.
CONCLUSIONS: Planned postoperative critical care was associated with a lower rate
of complications after elective colorectal surgery.

The Obesity Factor: How Cardiorespiratory Fitness is Estimated More Accurately in People with Obesity.

Königstein K, Klenk C, Rossmeissl A, Baumann S, Infanger D, Hafner
B, Hinrichs T, Hanssen H, Schmidt-Trucksäss A

Obesity (Silver Spring). 2018 Feb;26(2):291-298. doi: 10.1002/oby.22078. Epub
2017 Dec 12.

OBJECTIVE: Cardiopulmonary exercise testing is clinically used to estimate
cardiorespiratory fitness (CRF). The relation to total body mass (TBM) leads to
an underestimation of CRF in people with obesity and to inappropriate prognostic
and therapeutic decisions. This study aimed to determine body composition-derived
bias in the estimation of CRF in people with obesity.
METHODS: Two hundred eleven participants (58.8% women; mean BMI 35.7 kg/m2
[± 6.94; 20.7-58.6]) were clinically examined, and body composition (InBody720;
InBody Co., Ltd., Seoul, South Korea) and spiroergometrical peak oxygen
consumption (VO2 peak) were assessed. The impacts of TBM, lean body mass (LBM),
and skeletal muscle mass (SMM) on CRF estimates were analyzed by the application
of respective weight models. Linear regression and plotting of residuals against
BMI were performed on the whole study population and two subgroups (BMI < 30
kg/m2 and BMI ≥ 30 kg/m2 ).
RESULTS: For every weight model, Δmean VO2 peak (expected - measured) was
positive. LBM and SMM had a considerable impact on VO2 peak demand (P = 0.001;
ΔR2  = 2.3%; adjusted R2  = 56% and P = 0.001; ΔR2 = 2.7%; adjusted R2  = 56%),
whereas TBM did not. Confounding of body composition on VO2 peak did not differ
in LBM and SMM.
CONCLUSIONS: TBM-adjusted overestimation of relative VO2 demand is much higher in
people with obesity than in those without. LBM or SMM adjustment may be superior
alternatives, although small residual body composition-derived bias remains.

Determining Cardiorespiratory Fitness with Precision: Compendium of Findings from the FRIEND Registry.

Kaminsky LA; Myers J; Arena R;

Progress In Cardiovascular Diseases [Prog Cardiovasc Dis] 2018 Oct 29. Date of Electronic Publication: 2018 Oct 29.

Healthy living (HL) behaviors and characteristics are central to both preventing and treating a myriad of chronic diseases; a key HL characteristic is cardiorespiratory fitness (CRF). Knowing an individual’s CRF provides vital information when assessing health status and formulating a plan of care. Normative reference values as well as thresholds that denote varying degrees of health and future risk exist for measures of CRF. However, improving upon the precision of CRF reference standards according to key factors as well as precision in how CRF assessments can be used to assess health status and prognosis is needed. The current review will: 1) provide an overview of current approaches to CRF assessment and interpretations; 2) describe more recent efforts to improve upon the precision of CRF values; and 3) describe the Fitness Registry and the Importance of Exercise: A National Data Base (FRIEND) for the precision of CRF as a clinical measure.

High intensity interval training protects the heart during increased metabolic demand in patients with type 2 diabetes: a randomised controlled trial.

Suryanegara J; Cassidy S; Ninkovic V; Popovic D; Grbovic M; Okwose N; Trenell MI; MacGowan GG; Jakovljevic DG;

Acta Diabetologica [Acta Diabetol] 2018 Nov 01. Date of Electronic Publication: 2018 Nov 01.

Aim: The present study assessed the effect of high intensity interval training on cardiac function during prolonged submaximal exercise in patients with type 2 diabetes.
Methods: Twenty-six patients with type 2 diabetes were randomized to a 12 week of high intensity interval training (3 sessions/week) or standard care control group. All patients underwent prolonged (i.e. 60 min) submaximal cardiopulmonary exercise testing (at 50% of previously assess maximal functional capacity) with non-invasive gas-exchange and haemodynamic measurements including cardiac output and stroke volume before and after the intervention.
Results: At baseline (prior to intervention) there was no significant difference between the intervention and control group in peak exercise oxygen consumption (20.3 ± 6.1 vs. 21.7 ± 5.5 ml/kg/min, p = 0.21), and peak exercise heart rate (156.3 ± 15.0 vs. 153.8 ± 12.5 beats/min, p = 0.28). During follow-up assessment both groups utilized similar amount of oxygen during prolonged submaximal exercise (15.0 ± 2.4 vs. 15.2 ± 2.2 ml/min/kg, p = 0.71). However, cardiac function i.e. cardiac output during submaximal exercise decreased significantly by 21% in exercise group (16.2 ± 2.7-12.8 ± 3.6 L/min, p = 0.03), but not in the control group (15.7 ± 4.9-16.3 ± 4.1 L/min, p = 0.12). Reduction in exercise cardiac output observed in the exercise group was due to a significant decrease in stroke volume by 13% (p = 0.03) and heart rate by 9% (p = 0.04).
Conclusion: Following high intensity interval training patients with type 2 diabetes demonstrate reduced cardiac output during prolonged submaximal cardiopulmonary exercise testing. Ability of patients to maintain prolonged increased metabolic demand but with reduced cardiac output suggests cardiac protective role of high intensity interval training in type 2 diabetes.

 

Oxygen Consumption at Anaerobic Threshold Predicts Cardiac Events After Heart Transplantation.

Tsai HY; Tsai WJ; Kuo LY; Lin YS; Chen BY; Lin WH; Shen SL; Huang HY;

Transplantation Proceedings [Transplant Proc] 2018 Nov; Vol. 50 (9), pp. 2742-2746. Date of Electronic Publication: 2018 Mar 19.

Objectives: The ventilatory efficiency and functional capacity measured by the cardiopulmonary exercise test (CPET) have been used as important prognostic variables in congestive heart failure. This study sought to identify whether these predictors before heart transplantation (HTX) play a key role in predicting adverse events in patients with heart failure after HTX.
Methods: This was a retrospective cohort study design. HTX recipients were included for analysis. Ventilation to carbon dioxide production slope (VE/VCO2 slope) and oxygen consumption (VO2) during exercise were collected by CPET, which represented ventilator efficiency and functional capacity respectively. Cardiac-related events 2 years after HTX were recorded by chart review. We divided patients into 2 groups based on VE/VCO2 slope = 34, peak VO2 = 14 mL/kg/min and VO2 at aerobic threshold (AT) = 11 mL/kg/min. Kaplan-Meier survival curves was used to represent the events rate between groups and Log rank test was used to test significance.
Results: A total of 87 patients after HTX were included. Mean (SD) age was 48 (11) years and 73 were male; 28 subjects suffered from events, and 76 cardiac events were recorded. The mean (SD) data of peak VO2, VO2 at AT, and VE/VCO2 slope analyzed from CPET were 17.8 (5.6) mL/kg/min, 15.4 (4.4) mL/kg/min, and 33.1 (8.2) mL/kg/min, respectively. Lower VO2 at AT contributed to increase events rate (P < .05).
Conclusion: Aerobic capacity may better predict 2-year cardiac events in patients after HTX. Strategies to improve aerobic capacity should be focused on in the cohort.