Heart Rate Reserve in Fontan Patients: Chronotropic Incompetence or Hemodynamic Limitation?

Abstract Background The prevalence of chronotropic incompetence (CI) in heart failure (HF) population is high and negatively impacts prognosis. In HF patients with an implanted cardiac resynchronisation therapy (CRT) device and severe CI, the effect of rate adaptive pacing on patient outcomes is unclear. Closed loop stimulation (CLS) based on cardiac impedance measurement may be an optimal method of heart rate adaptation according to metabolic need in HF patients with severe CI. Purpose This is the first study evaluating the effect of CLS on the established prognostic parameters assessed by the cardio-pulmonary exercise (CPX) testing and on quality of life (QoL) of the patients. Methods A randomised, controlled, double-blind and crossover pilot study has been performed in CRT patients with severe CI defined as the inability to achieve 70% of the age-predicted maximum heart rate (APMHR). After baseline assessment, patients were randomised to either DDD-CLS pacing (group 1) or DDD pacing at 40 bpm (group 2) for a 1-month period, followed by crossover for another month. At baseline and at 1- and 2-month follow-ups, a CPX was performed and QoL was assessed using the EQ-5D-5L questionnaire. The main endpoints were the effect of CLS on ventilatory efficiency (VE) slope (evaluated by an independent CPX expert), the responder rate defined as an improvement (decrease) of the VE slope by at least 5%, percentage of maximal predicted heart rate reserve (HRR) achieved, and QoL. Results Of the 36 patients enrolled in the study, 20 fulfilled the criterion for severe CI and entered the study follow-up (mean age 68.9±7.4 years, 70% men, LVEF=41.8±9.3%, 40%/60% NYHA class II/III). Full baseline and follow-up datasets were obtained in 17 patients. The mean VE slope and HRR at baseline were 34.4±4.4 and 49.6±23.8%, respectively, in group 1 (n=7) and 34.5±12.2 and 54.2±16.1% in group 2 (n=10). After completing the 2-month CPX, the mean difference between DDD-CLS and DDD-40 modes was −2.4±8.3 (group 1) and −1.2±3.5 (group 2) for VE slope, and 17.1±15.5% (group 1) and 8.7±18.8% (group 2) for HRR. Altogether, VE slope improved by −1.8±2.95 (p=0.31) in DDD-CLS versus DDD-40, and HRR improved by 12.9±8.8% (p=0.01). The VE slope decreased by ≥5% in 47% of patients (“responders to CLS”). The mean difference in the QoL between DDD-CLS and DDD-40 was 0.16±0.25 in group 1 and −0.01±0.05 in group 2, resulting in an overall increase by 0.08±0.08 in the DDD-CLS mode (p=0.13). Conclusion First results of the evaluation of the effectiveness of CLS in CRT patients with severe CI revealed that CLS generated an overall positive effect on well-established surrogate parameters for prognosis. About one half of the patients showed CLS response in terms of improved VE slope. In addition, CLS improved quality of life. Further clinical research is needed to identify predictors that can increase the responder rate and to confirm improvement in clinical outcomes. Funding Acknowledgement Type of funding source: Private company. Main funding source(s): Biotronik SE & Co. KG

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Exercise chronotropic incompetence phenotypes the level of cardiovascular risk and exercise gas exchange impairment in the general population. An analysis of the Euro-EX prevention trial

European Journal of Preventive Cardiology ◽

10.1177/2047487319863506 ◽

2019 ◽

Vol 27 (5) ◽

pp. 526-535 ◽

Cited By ~ 2

Author(s):

Pietro Laforgia ◽

Francesco Bandera ◽

Eleonora Alfonzetti ◽

Marco Guazzi

Keyword(s):

Heart Rate ◽

Cardiovascular Risk ◽

Gas Exchange ◽

Left Ventricular ◽

Prevention Trial ◽

Volume Index ◽

Maximal Heart Rate ◽

Heart Rate Reserve ◽

Peak Heart Rate ◽

Apparently Healthy

Background Chronotropic insufficiency (CI) is defined as the inability of the heart to increase its rate commensurate with increased demand. Exercise CI is an established predictor of major adverse cardiovascular events in patients with cardiovascular diseases. Aim The aim of this study was to evaluate how exercise CI phenotypes different levels of cardiovascular risk and how it may better perform in defining cardiovascular risk when analysed in the context of cardiopulmonary exercise test (CPET)-derived measures and standard echocardiography in a healthy population with variable cardiovascular risk profile. Methods Apparently healthy individuals ( N = 702, 53.8% females) with at least one major cardiovascular risk factor (MCVRF; hypertension, diabetes, tabagism, dyslipidaemia, body mass index > 25), enrolled in the Euro-EX prevention trial, underwent CPET. CI was defined as the inability to reach 80% of the chronotropic index, that is, the ratio of peak heart rate – rest heart rate/peak heart rate – age predicted maximal heart rate (AMPHR: 220 – age), they were divided into four groups according to the heart rate reserve (<80%>) and respiratory gas exchange ratio (RER; < 1.05>) as a marker of achieved maximal performance. Subjects with a RER < 1.05 ( n = 103) were excluded and the final population ( n = 599) was divided into CI group ( n = 472) and no-CI group ( n = 177). Results Compared with no-CI, CI subjects were more frequently females with a history of hypertension in a high rate. CI subjects also exhibited a significantly lower peak oxygen uptake (VO2) and circulatory power and an echocardiographic pattern indicative of higher left atrial volume index and left ventricular mass index. An inverse stepwise relationship between heart rate reserve and number of MCVRFs was observed (one MCVRF: 0.71 ± 0.23; two MCVRFs: 0.68 ± 0.24, three MCVRFs: 0.64 ± 0.20; four MCVRFs: 0.64 ± 0.23; five MCVRFs: 0.57 ± 18; p < 0.01). In multivariate analysis the only variable found predicting CI was peak VO2 ( p < 0.05; odds ratio 0.91; confidence interval 0.85–0.97). Conclusions In a population of apparently healthy subjects, exercise CI is common and phenotypes the progressive level of cardiovascular risk by a tight relationship with MCVRFs. CI patients exhibit some peculiar abnormal exercise gas exchange patterns (lower peak VO2 and exercise oscillatory ventilation) and echo-derived measures (higher left atrium size and left ventricle mass) that may well anticipate evolution toward heart failure.

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Understanding cognitive performance during exercise in Reserve Officers’ Training Corps: establishing the executive function-exercise intensity relationship

Journal of Applied Physiology ◽

10.1152/japplphysiol.00483.2020 ◽

2020 ◽

Vol 129 (4) ◽

pp. 846-854

Author(s):

Brandon L. Stone ◽

Madison Beneda-Bender ◽

Duncan L. McCollum ◽

Jongjoo Sun ◽

Joseph H. Shelley ◽

...

Keyword(s):

Heart Rate ◽

Executive Function ◽

Executive Functioning ◽

Exercise Intensity ◽

Cognitive Change ◽

Heart Rate Reserve ◽

Graded Exercise ◽

The Brain ◽

Training Corps ◽

Reserve Officers Training Corps

The executive functioning aspect of cognition was evaluated during graded exercise in Reserve Officers’ Training Corps cadets. Executive function declined at exercise intensities of ≥80% of heart rate reserve. The decline in executive function was coupled with declines in the oxygenation of the prefrontal cortex, the brain region responsible for executive functioning. These data define the executive function-exercise intensity relationship and provide evidence supporting the reticular activation hypofrontality theory as a model of cognitive change.

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Methodological and practical application issues in exercise prescription using the heart rate reserve and oxygen uptake reserve methods

Journal of Science and Medicine in Sport ◽

10.1016/j.jsams.2010.07.008 ◽

2011 ◽

Vol 14 (1) ◽

pp. 46-57 ◽

Cited By ~ 36

Author(s):

Felipe Amorim da Cunha ◽

Paulo de Tarso Veras Farinatti ◽

Adrian W. Midgley

Keyword(s):

Heart Rate ◽

Oxygen Uptake ◽

Exercise Prescription ◽

Heart Rate Reserve ◽

Practical Application

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HEART RATE SCORE, A MEASURE RELATED to CHRONOTROPIC INCOMPETENCE IN PACEMAKER PATIENTS

Heart Rhythm O2 ◽

10.1016/j.hroo.2021.02.002 ◽

2021 ◽

Author(s):

Arjun D. Sharma ◽

Mark Richards ◽

Brian Olshansky ◽

Nicholas Wold ◽

Paul Jones ◽

...

Keyword(s):

Heart Rate ◽

Chronotropic Incompetence ◽

Rate Score

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Heart rate reserve as a predictor of cardiovascular and all-cause mortality in men

Medicine & Science in Sports & Exercise ◽

10.1097/00005768-200212000-00003 ◽

2002 ◽

Vol 34 (12) ◽

pp. 1873-1878 ◽

Cited By ~ 30

Author(s):

YILING J. CHENG ◽

CAROLINE A. MACERA ◽

TIMOTHY S. CHURCH ◽

STEVEN N. BLAIR

Keyword(s):

Heart Rate ◽

Heart Rate Reserve ◽

All Cause Mortality

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Abstract P319: Association of Heart Rate Reserve with Incidence of Hypertension in Men

Circulation ◽

10.1161/circ.127.suppl_12.ap319 ◽

2013 ◽

Vol 127 (suppl_12) ◽

Author(s):

Vivek K Prasad ◽

Gregory A Hand ◽

Mei Sui ◽

Duck C Lee ◽

Deepika Shrestha ◽

...

Keyword(s):

Heart Rate ◽

Exercise Test ◽

Heavy Drinking ◽

Risk Groups ◽

Hazard Ratio ◽

Maximal Heart Rate ◽

Heart Rate Reserve ◽

Incident Hypertension ◽

The Difference ◽

Design And Methods

Abstract Objectives— We examined the association between heart rate reserve (HRR) and incident hypertension in men in the Aerobics Center Longitudinal Study. Research design and Methods— A total of 10418 healthy normotensive men, who did not have an abnormal electrocardiogram or a history of heart attack, stroke, cancer, or diabetes, performed a maximal treadmill exercise test and were followed for the incidence of hypertension. HRR was defined as the difference between maximal heart rate during exercise test and resting heart rate. Results— During a mean follow-up of 6 years, there were 2831 cases of incident hypertension. Compared with men in the reference category (the lowest quartile of HRR), the risk of incident hypertension was significantly lower in the highest quartile of HRR with a hazard ratio 0.67 (95% CI: 0.60-0.75) when adjusted for age and baseline examination year. Further adjustment for smoking, heavy drinking, body mass index (BMI), resting systolic and diastolic blood pressure, cholesterol, blood glucose and cardio respiratory fitness, resulted a hazard ratio of 0.84 (95% CI:0.74-0.95). This result was almost similar when we stratified them into younger and older men with hazard ratio of 0.77(95% CI: 0.62-0.98) and 0.78 (95% CI: 0.66-0.90) respectively. We also found a significant lower hypertension risk associated with higher HRR among high risk groups such as overweight, low fitness, or prehypertension with hazard ratio of 0.82(95% CI:0.70-0.97), 0.80(95% CI:0.67-0.96), 0.76(95% CI:0.64-0.88) respectively. Conclusion— Risk of Incident hypertension was significantly lower in men with higher HRR. High HRR was also associated with lower risk of developing hypertension irrespective of age and status of risk factors such as high BMI, low fitness and prehypertension. Therefore, HRR may be considered as a reliable exercise parameter for predicting the risk of incident hypertension.

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Cardiovascular Effects of Aerobic Exercise With Self-Selected or Predetermined Intensity in Adolescents With Obesity

Pediatric Exercise Science ◽

10.1123/pes.2020-0104 ◽

2021 ◽

pp. 1-7

Author(s):

Tércio A.R. Barros ◽

Wagner L. do Prado ◽

Thiago R.S. Tenório ◽

Raphael M. Ritti-Dias ◽

Antônio H. Germano-Soares ◽

...

Keyword(s):

Blood Pressure ◽

Body Mass Index ◽

Heart Rate ◽

Pulse Pressure ◽

Exercise Intensity ◽

Pulse Wave ◽

Augmentation Index ◽

Cardiovascular Effects ◽

Heart Rate Reserve ◽

Central Pulse Pressure

This study compared the effects of self-selected exercise intensity (SEI) versus predetermined exercise intensity (PEI) on blood pressure (BP) and arterial stiffness in adolescents with obesity. A total of 37 adolescents, 14.7 (1.6) years old, body mass index ≥95th percentile were randomly allocated into SEI (n = 18; 12 boys) or PEI (n = 19; 13 boys). Both groups exercised for 35 minutes on a treadmill, 3 times per week, for 12 weeks. The SEI could set the speed at the beginning of the sessions and make changes every 5 minutes. The PEI adolescents were trained at an intensity set at 60% to 70% of heart rate reserve. Brachial and central BP, pulse pressure, augmentation index, and carotid–femoral pulse wave were determined at baseline and after 12 weeks. Both groups reduced brachial systolic BP (SEI, Δ = −9 mm Hg; PEI, Δ = −4 mm Hg; P < .01), central systolic BP (SEI, Δ = −4 mm Hg; PEI, Δ = −4 mm Hg; P = .01), and central pulse pressure (SEI, Δ = −4 mm Hg; PEI, Δ = −3 mm Hg; P = .02) without differences between groups. No changes in the augmentation index and carotid–femoral pulse wave were observed in either group. The SEI induced similar changes in various cardiovascular outcomes compared with PEI in adolescents with obesity.

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