Van Edom C; Jacobs S; Fresiello L; Vandersmissen K; Vandenbriele C; Droogné W; Meyns B;

European journal of cardio-thoracic surgery : official journal of the European Association for Cardio-thoracic Surgery [Eur J Cardiothorac Surg] 2022 Feb 10. Date of Electronic Publication: 2022 Feb 10.

Objectives: N-terminal pro-brain natriuretic peptide (NT-proBNP) is a widely used biomarker in clinical practice in the context of heart failure. Little is known about the long-term evolution of NT-proBNP levels in left ventricular assist device (LVAD) recipients. Besides this, the potential correlation of NT-proBNP with exercise capacity on the long term after LVAD implantation has not been previously studied.
Methods: We retrospectively analysed 132 single-centre LVAD recipient records (HeartMate II/III; HeartWare; between March 2007 and January 2018; mean follow-up 559 days). Blood samples, 6-min walking test (6MWT) and maximal cardiopulmonary exercise test were performed in a standardized way.
Results: Pre-LVAD NT-proBNP levels were increased (9736 ± 1072 ng/l) and dropped significantly after implantation [14 days: 4360 ± 545 ng/l (P < 0.0001), 6 months: 1485 ± 139 ng/l (P < 0.0001)]. Afterwards a steady state was reached during follow-up (after 1 year: 1592 ± 214 ng/l, after 5 years: 1679 ± 311 ng/l). Submaximal exercise capacity significantly improved postoperatively [percentage of the predicted distance walked during the 6MWT 50 ± 2% (0-3 months); 61 ± 2% (3-6 months, P < 0.001)], with a steady state afterwards [66 ± 2% (6-12 months, P = 0.08); 64 ± 3%, P = 0.70 later on]. We found a gradual increment of percentage of the expected peak oxygen consumption postoperatively [44 ± 2% (0-3 months); 49 ± 2% (3-6 months); 52 ± 2% (6-12 months); 53 ± 1% (after 12 months)] with a significant improvement between 0 and 3 months versus after the first year on LVAD. Furthermore, we showed a significant moderate correlation between NT-proBNP levels and results at both the 6MWT (correlation coefficient: -0.31, P < 0.0001) and cardiopulmonary exercise testing (correlation coefficient: -0.28, P < 0.0001).
Conclusions: NT-proBNP decreased on LVAD support. We showed that submaximal (6MWT) and maximal exercise capacity (cardiopulmonary exercise testing) improve after LVAD implantation and demonstrated an inverse correlation of both tests with NT-proBNP levels.

Hiraiwa H; Okumura T; Sawamura A; Araki T; Mizutani T; Kazama S; Kimura Y; Shibata N; Oishi H; Kuwayama T; Kondo T; Furusawa K; Morimoto R; Adachi T; Yamada S; Mutsuga M; Usui A; Murohara T;

BMC research notes [BMC Res Notes] 2022 Feb 10; Vol. 15 (1), pp. 40.
Date of Electronic Publication: 2022 Feb 10.

Objective: Spleen volume increases in patients with advanced heart failure (HF) after left ventricular assist device (LVAD) implantation. However, the relationship between spleen volume and exercise tolerance (peak oxygen consumption [VO ₂ ]) in these patients remains unknown. In this exploratory study, we enrolled 27 patients with HF using a LVAD (median age: 46 years). Patients underwent blood testing, echocardiography, right heart catheterization, computed tomography (CT), and cardiopulmonary exercise testing. Spleen size was measured using CT volumetry, and the correlations/causal relationships of factors affecting peak VO ₂ were identified using structural equation modeling.
Results: The median spleen volume was 190.0 mL, and peak VO ₂ was 13.2 mL/kg/min. The factors affecting peak VO ₂ were peak heart rate (HR; β = 0.402, P = .015), pulmonary capillary wedge pressure (PCWP; β =  - 0.698, P = .014), right ventricular stroke work index (β = 0.533, P = .001), blood hemoglobin concentration (β = 0.359, P = .007), and spleen volume (β = 0.215, P = .041). Spleen volume correlated with peak HR, PCWP, and hemoglobin concentration, reflecting sympathetic activity, cardiac preload, and oxygen-carrying capacity, respectively, and was thus related to peak VO ₂ . These results suggest an association between spleen volume and exercise tolerance in advanced HF.

Chuang ML; Hsieh BY; Lin IF;

Medicine [Medicine (Baltimore)] 2022 Feb 11; Vol. 101 (6), pp. e28800.

Abstract: A high dead space (VD) to tidal volume (VT) ratio during peak exercise (VD/VTpeak) is a sensitive and consistent marker of gas exchange abnormalities; therefore, it is important in patients with chronic obstructive pulmonary disease (COPD). However, it is necessary to use invasive methods to obtain VD/VTpeak, as noninvasive methods, such as end-tidal PCO2 (PETCO2peak) and PETCO2 adjusted with Jones’ equation (PJCO2peak) at peak exercise, have been reported to be inconsistent with arterial PCO2 at peak exercise (PaCO2peak). Hence, this study aimed to generate prediction equations for VD/VTpeak using statistical techniques, and to use PETCO2peak and PJCO2peak to calculate the corresponding VD/VTpeaks (i.e., VD/VTpeakETVD/VTpeakJ).A total of 46 male subjects diagnosed with COPD who underwent incremental cardiopulmonary exercise tests with PaCO2 measured via arterial catheterization were enrolled. Demographic data, blood laboratory tests, functional daily activities, chest radiography, two-dimensional echocardiography, and lung function tests were assessed.In multivariate analysis, diffusing capacity, vital capacity, mean inspiratory tidal flow, heart rate, and oxygen pulse at peak exercise were selected with a predictive power of 0.74. There were no significant differences in the PCO2peak values and the corresponding VD/VTpeak values across the three types (both p = NS).In subjects with COPD, VD/VTpeak can be estimated using statistical methods and the PETCO2peak and PJCO2peak. These methods may have similar predictive power and thus can be used in clinical practice.

Bédat B; Koliakos E; Demarchi MS; Perentes J; Licker MJ; Triponez F; Karenovics W; Gonzalez M;

Interactive cardiovascular and thoracic surgery [Interact Cardiovasc Thorac Surg] 2022 Feb 14.
Date of Electronic Publication: 2022 Feb 14.

Objectives: The aim of this study was to identify whether steeper V.E/V. CO2 slope was associated with cardiopulmonary complications (CPC) after anatomical resection by video-assisted thoracic surgery. Long-term survival was analysed as secondary outcome.
Methods: We reviewed the files of all consecutive patients who underwent pulmonary anatomical resections by video-assisted thoracic surgery between January 2010 and October 2020 at the Centre for Thoracic Surgery of Western Switzerland. Logistic regression was used to investigate the risk of CPC associated with the V.E/V.CO2 slope and other possible confounders. Survival was analysed with Kaplan-Meier curves. Risk factors associated with survival were analysed with a Cox proportional hazards model.
Results: The V.E/V.CO2 slope data were available for 145 patients [F/M: 66/79; mean age (standard deviation): 65.8 (8.9)], which were included in the analysis. Patients underwent anatomical resection [lobectomy (71%) or segmentectomy (29%)] mainly for lung cancer (96%). CPC and all-cause 90-day mortality were 29% and 1%, respectively. The mean (standard deviation) percentage of the predicted V.O2peak was 70% (17). Maximum effort during cardiopulmonary exercise test was reached in only 31% of patients. The V.E/V.CO2 slope (standard deviation) was not different if the maximum effort was reached or not [39 (6) vs 37 (7), P = 0.21]. V.E/V.CO2 slope >35 was associated with an increased risk of CPC (odds ratio 2.9, 95% confidence interval 1.2, 7.2, P = 0.020). V.E/V.CO2 slope >35 was not associated with shorter survival censored for lung cancer-related death.
Conclusions: V . E/V.CO2 slope >35 is significantly associated with postoperative CPC after anatomical resections by video-assisted thoracic surgery.

Sivakumar J, Forshaw MJ, Lam S, Peters CJ, Allum WH, Whibley J, Sinclair RCF, Snowden CP, Hii MW, Sivakumar H, Read M

Dis Esophagus. 2022 Feb 9:doac005. doi: 10.1093/dote/doac005. Online ahead of print.

Preoperative cardiopulmonary exercise testing (CPET) provides an objective assessment of aerobic fitness in patients undergoing surgery. While peak oxygen uptake during exercise (VO2peak) and anaerobic threshold have demonstrated a moderate correlation with the development of complications following esophagectomy, no clinically useful threshold values have been defined. By pooling patient level data from existing studies, we aimed to define optimal thresholds for preoperative CPET parameters to predict patients at high risk of postoperative complications. Studies reporting on the relationship between preoperative CPET variables and post-esophagectomy complications were determined from a comprehensive literature search. Patient-level data were obtained from six contributing centers for pooled-analyses. Outcomes of interest included cardiopulmonary and non-cardiopulmonary complications, unplanned intensive care unit readmission, and 90-day and 12-month all-cause mortality. Receiver operating characteristic curves and logistic regression models estimated the predictive value of CPET parameters for each individual outcome of interest. This analysis comprised of 621 patients who underwent CPET prior to esophagectomy during the period from January 2004 to March 2017. For both anaerobic threshold and VO2peak, none of the receiver operating characteristic curves achieved an area under the curve value > 0.66 for the outcomes of interest. The discriminatory ability of CPET for determining high-risk patients was found to be poor in patients undergoing an esophagectomy. CPET may only carry an adjunct role to clinical decision-making.

Rovai S; Contini M; Sciomer S; Vignati C; Agostoni P;

International journal of cardiology [Int J Cardiol] 2022 Jan 26.
Date of Electronic Publication: 2022 Jan 26.

Background: Cardiopulmonary exercise test (CPET) has an important role in assessing heart failure (HF) patients. Among CPET parameters, a pivotal role is attributed to the anaerobic threshold (AT), normally determined by V-slope, ventilatory equivalent and end-tidal methods. In about 10% of healthy subjects, a lack of concordance between these methods has been reported. This event was named double AT (DT). We hypothesized that DT was due to a delay in chemoreflex response.
Methods: We reanalyzed CPET data of two cross-over studies in which we compared CPET in stable HF patients treated for two months with bisoprolol and carvedilol. In chronic HF, carvedilol has a greater sympathetic inhibition than bisoprolol, as shown by a lower chemoreflex response.
Results: In 87 patients, we identified DT in 46% and 66% of cases during bisoprolol and carvedilol treatment, respectively (p < 0.01). Compared with bisoprolol, carvedilol treatment was associated to a lower peak oxygen uptake (from 17.4 ± 4.3 to 16.4 ± 4.1 mL/min/kg) and oxygen pulse (from 11.8 ± 2.9 to 11.1 ± 2.9 mL/min/kg) suggestive of lower peak cardiac output.
Conclusions: DT is frequent in HF and more often with carvedilol than bisoprolol treatment, may be due to a greater inhibition of sympathetic tone and prolonged circulatory time. These findings open an unexplored research field.

Zhou N; Scoubeau C; Forton K; Loi P; Closset J; Deboeck G; Moraine JJ; Klass M; Faoro V;

Obesity facts [Obes Facts] 2022 Jan 27, pp. 1-9.
Date of Electronic Publication: 2022 Jan 27.

Introduction: Patients undergoing weight loss surgery do not improve their aerobic capacity or peak oxygen uptake (VO2peak) after bariatric surgery and some still complain about asthenia and/or breathlessness. We investigated the hypothesis that a post-surgery muscular limitation could impact the ventilatory response to exercise by evaluating the post-surgery changes in muscle mass, strength, and muscular aerobic capacity, measured by the first ventilatory threshold (VT).
Methods: Thirteen patients with obesity were referred to our university exercise laboratory before and 6 months after bariatric surgery and were matched by sex, age, and height to healthy subjects with normal weight. All subjects underwent a clinical examination, blood sampling, and body composition assessment by dual-energy X-ray absorptiometry, respiratory and limb muscle strength assessments, and cardiopulmonary exercise testing on a cyclo-ergometer.
Results: Bariatric surgery resulted in a loss of 34% fat mass, 43% visceral adipose tissue, and 12% lean mass (LM) (p < 0.001). Absolute handgrip, quadriceps, or respiratory muscle strength remained unaffected, while quadriceps/handgrip strength relative to LM increased (p < 0.05). Absolute VO2peak or VO2peak/LM did not improve and the first VT was decreased after surgery (1.4 ± 0.3 vs. 1.1 ± 0.4 L min-1, p < 0.05) and correlated to the exercising LM (LM legs) (R = 0.84, p < 0.001).
Conclusions: Although bariatric surgery has numerous beneficial effects, absolute VO2peak does not improve and the weight loss-induced LM reduction is associated to an altered muscular aerobic capacity, as reflected by an early VT triggering early exercise hyperventilation.

Woodfield JC; Clifford K; Wilson GA; Munro F; Baldi JC;

Scandinavian journal of medicine & science in sports [Scand J Med Sci Sports] 2022 Jan 28.
Date of Electronic Publication: 2022 Jan 28.

Purpose: Improving cardiopulmonary reserve, or peak oxygen consumption(V˙O _2peak ), may reduce postoperative complications; however, this may be difficult to achieve between diagnosis and surgery. Our primary aim was to assess the efficacy of an approximate 14-session, preoperative high-intensity interval training(HIIT) program to increaseV˙O _2peak by a clinically relevant 2 ml·kg ^-1 ·min ^-1 . Our secondary aim was to document clinical outcomes.
Methodology: In this prospective study, participants aged 45-85 undergoing major abdominal surgery were randomized to standard care or 14 sessions of HIIT over 4 weeks. HIIT sessions involved approximately 30 min of stationary cycling. Interval training alternated 1 min of high (with the goal of reaching 90% max heart rate at least once during the session) and low/moderate-intensity cycling. Cardiopulmonary exercise testing(CPET) measured the change inV˙O _2peak from baseline to surgery. Clinical outcomes included postoperative complications, length of stay(LOS), and Short Form 36 quality of life questionnaire(SF-36).
Results: Of 63 participants, 46 completed both CPETs and 50 completed clinical follow-up. There was a significant improvement in the HIIT group’s mean ± SDV˙O _2peak (HIIT 2.87 ± 1.94 ml·kg ¹ ·min ^-1 vs standard care 0.15 ± 1.93, with an overall difference of 2.73 ml·kg ¹ ·min ^-1 95%CI [1.53, 3.93] p < 0.001). There were no statistically significant differences between groups for clinical outcomes, although the observed differences consistently favored the exercise group. This was most notable for total number of complications (0.64 v 1.16 per patient, p = 0.07), SF-36 physical component score (p = 0.06), and LOS (mean 5.5 v 7.4 days, p = 0.07).
Conclusions: There was a significant improvement inV˙O _2peak with a four-week preoperative HIIT program. Further appropriately powered work is required to explore the impact of preoperative HIIT on postoperative clinical outcomes.

Dos Santos PB; Simões RP; Goulart CL; Arêas GPT; Marinho RS; Camargo PF; Roscani MG; Arbex RF; Oliveira CR; Mendes RG; Arena R;Borghi-Silva A;

Scientific reports [Sci Rep] 2022 Jan 31; Vol. 12 (1), pp. 1592.
Date of Electronic Publication: 2022 Jan 31.

Our aim was to evaluate: (1) the prevalence of coexistence of heart failure (HF) and chronic obstructive pulmonary disease (COPD) in the studied patients; (2) the impact of HF + COPD on exercise performance and contrasting exercise responses in patients with only a diagnosis of HF or COPD; and (3) the relationship between clinical characteristics and measures of cardiorespiratory fitness; (4) verify the occurrence of cardiopulmonary events in the follow-up period of up to 24 months years. The current study included 124 patients (HF: 46, COPD: 53 and HF + COPD: 25) that performed advanced pulmonary function tests, echocardiography, analysis of body composition by bioimpedance and symptom-limited incremental cardiopulmonary exercise testing (CPET) on a cycle ergometer. Key CPET variables were calculated for all patients as previously described. The [Formula: see text] _E /[Formula: see text]CO ₂ slope was obtained through linear regression analysis. Additionally, the linear relationship between oxygen uptake and the log transformation of [Formula: see text] _E (OUES) was calculated using the following equation: [Formula: see text]O ₂  = a log [Formula: see text] _E  + b, with the constant ‘a’ referring to the rate of increase of [Formula: see text]O ₂ . Circulatory power (CP) was obtained through the product of peak [Formula: see text]O ₂ and peak systolic blood pressure and Ventilatory Power (VP) was calculated by dividing peak systolic blood pressure by the [Formula: see text] _E /[Formula: see text]CO ₂ slope. After the CPET, all patients were contacted by telephone every 6 months (6, 12, 18, 24) and questioned about exacerbations, hospitalizations for cardiopulmonary causes and death. We found a 20% prevalence of HF + COPD overlap in the studied patients. The COPD and HF + COPD groups were older (HF: 60 ± 8, COPD: 65 ± 7, HF + COPD: 68 ± 7). In relation to cardiac function, as expected, patients with COPD presented preserved ejection fraction (HF: 40 ± 7, COPD: 70 ± 8, HF + COPD: 38 ± 8) while in the HF and HF + COPD demonstrated similar levels of systolic dysfunction. The COPD and HF + COPD patients showed evidence of an obstructive ventilatory disorder confirmed by the value of %FEV ₁ (HF: 84 ± 20, COPD: 54 ± 21, HF + COPD: 65 ± 25). Patients with HF + COPD demonstrated a lower work rate (WR), peak oxygen uptake ([Formula: see text]O ₂ ), rate pressure product (RPP), CP and VP compared to those only diagnosed with HF and COPD. In addition, significant correlations were observed between lean mass and peak [Formula: see text]O ₂ (r: 0.56 p < 0.001), OUES (r: 0.42 p < 0.001), and O ₂ pulse (r: 0.58 p < 0.001), lung diffusing factor for carbon monoxide (D _LCO ) and WR (r: 0.51 p < 0.001), D _LCO and VP (r: 0.40 p: 0.002), forced expiratory volume in first second (FEV ₁ ) and peak [Formula: see text]O ₂ (r: 0.52; p < 0.001), and FEV ₁ and WR (r: 0.62; p < 0.001). There were no significant differences in the occurrence of events and deaths contrasting both groups. The coexistence of HF + COPD induces greater impairment on exercise performance when compared to patients without overlapping diseases, however the overlap of the two diseases did not increase the probability of the occurrence of cardiopulmonary events and deaths when compared to groups with isolated diseases in the period studied. CPET provides important information to guide effective strategies for these patients with the goal of improving exercise performance and functional capacity. Moreover, given our findings related to pulmonary function, body composition and exercise responses, evidenced that the lean mass, FEV ₁ and D _LCO influence important responses to exercise.

Lander BS; Layton AM; Garofano RP; Schwartz A; Engel DJ; Bello NA;

The American journal of cardiology [Am J Cardiol] 2022 Feb 01; Vol. 164, pp. 21-26.
Date of Electronic Publication: 2021 Nov 26.

Exercise stress testing is routinely performed to evaluate suspected coronary artery disease in older adults. However, the available data to predict and compare relative exercise capacity in the general population were developed using predominantly younger, healthy cohorts with few or no women. This study aimed to describe the exercise capacity of patients older than 75 years who underwent a clinically indicated Bruce protocol exercise stress test. This was a retrospective, cross-sectional study of 2,041 consecutive patients older than 75 years who performed a Bruce protocol exercise stress echocardiogram that was terminated because of maximal effort without ischemia at Columbia University Medical Center between April 10, 2009, and July 30, 2020. The analytic sample included 2,041 exercise stress tests in 786 women (median [interquartile range] age 79 [77 to 81] years) and 1,255 men (median [interquartile range] age 79 [77 to 82] years). Cardiovascular risk factors and clinical coronary disease were common and more prevalent in men than women. The median exercise time for men aged 76 to 80 years was 7:22 (minutes:seconds) and for women was 6:00 and significantly decreased in both genders as age increased (p <0.001). The mean (SD) METs achieved for women and men were 6.5 (1.6) and 7.7 (1.7), respectively. Most women (85%) and men (95%) completed the first stage, whereas only 32% of women and 64% of men completed the second stage. It was uncommon for women (3%) or men (15%) to complete the third stage. Fewer than 1% of patients completed the fourth stage, and none completed the fifth stage. At all ages, women had a lower exercise capacity than men. These data allow physicians to compare the exercise capacity of older patients who underwent a Bruce protocol exercise stress test more accurately to a representative sample of similarly aged adults.