Heart rate response at the onset of exercise in an apparently healthy cohort

The role of cardiopulmonary exercise testing in risk stratification and prognosis of atrial fibrillation: a scoping review of the literature

BACKGROUND

Cardiopulmonary exercise testing (CPET) is a significant tool for evaluating exercise capacity in healthy individuals and in various pulmonary and cardiovascular conditions, quantifying symptoms and predicting outcomes. Atrial fibrillation (AF) poses a significant burden on patients and health systems; a research marathon is ongoing for discovering the pathophysiologic substrate, natural history, prognostic tools and optimal treatment strategies for AF. Among the plethora of variables measured during CPET, there is a series of parameters of interest concerning AF.

METHODS

We conducted a scoping review aiming to identify significant CPET-related parameters linked to AF, as well as indicate the impact of other cardiac disease-related variables. We searched PubMed from its inception to 12 January 2022 for reports underlining the contribution of CPET in the assessment of patients with AF. Only clinical trials, observational studies and systematic reviews were included, while narrative reviews, expert opinions and other forms of manuscripts were excluded.

RESULTS

In our scoping review, we report a group of heterogeneous, thus noteworthy parameters relevant to the potential contribution of CPET in AF. CPET helps phenotype AF populations, evaluates exercise capacity after cardioversion or catheter ablation, and assesses heart rate response to exercise; peak VO₂ and VE/VCO₂, commonly measured indices during CPET, also serve as prognostic tools in patients with AF and heart failure.

CONCLUSIONS

CPET seems to hold a clinically important predictive value for future cardiovascular events both in patients with pre-existing cardiac conditions and in healthy individuals. CPET variables may play a fundamental role in the prediction of future AF-related events.

Heart rate response to alarm tones in firefighters

OBJECTIVE

To examine cardiovascular responses to medical (MED) and fire (FIRE) alarm tones in firefighters.

METHODS

Heart rate was collected throughout 24-h shifts (N = 41). Call logs were utilized post hoc to identify heart rate at the time the alarm sounded (TIME_TONE), peak heart rate following the alarm (TIME_PEAK), and heart rate at the time of station departure (TIME_DEPART) for MED and FIRE calls. A 2X3 (TONE x TIME) split-plot mixed-model repeated-measures analysis of variance (ANOVA) and least significant differences tests examined the influence of tone type on heart rate, expressed as a percent of age estimated maximum. Bivariate Pearson correlations examined the relationship between body mass index (BMI) and TIME_PEAK and TIME_DEPART. An alpha of 0.05 determined statistical significance and Bonferroni Corrections were applied to post hoc comparisons (p < 0.017).

RESULTS

Follow-up analyses for the significant 2 × 3 repeated-measures ANOVA (p = 0.035) indicated differences in heart rate for MED (p < 0.001) and FIRE (p < 0.001) where TIME_TONE < TIME_PEAK, TIME_TONE < TIME_DEPART, and TIME_PEAK > TIME_DEPART. There was a non-significant simple effect of time for MED and FIRE at TIME_TONE (p = 0.259), but significant effects of tone type where FIRE > MED at TIME_PEAK (p < 0.001) and TIME_DEPART (p = 0.002). There was a significant small positive relationship between BMI and TIME_PEAK (p = 0.002) and TIME_DEPART (p < 0.001) for MED only.

CONCLUSIONS

Alarms increased heart rates to a greater extent in FIRE than MED calls. Higher BMI was related to greater heart rate responses in MED but was unrelated to FIRE response.