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Abstract: The incidence of adverse cardiovascular events is higher among spectators of exciting sports events, but the mechanistic link between the events is not known. We assessed the heart rate (HR) and blood pressure (BP) dynamics of enthusiastic male ice hockey spectators (60±9years) with coronary artery disease (CAD) during Finnish national league ice hockey play-off final matches. Twenty-four-hour ambulatory ECG (n =55) and BP (n =17) were recorded at the time of the match and on a control day. Beat-to-beat R–R intervals and BP were recorded during the match and a bicycle exercise at equal HR levels (n =21). Systolic and diastolic BP were significantly higher 1h before, during, and 1h after the match than on the control day, e.g., the highest systolic BP was 180±14 vs. 145±15 and diastolic 103±13 vs. 82±11mmHg (p <0.001 for both). HR was higher throughout the match (p <0.05) and remained elevated 2h after the match (p <0001), and measures of HR variability were decreased during the match (p <0.01). Low-frequency variability in BP was higher during the match than during the exercise test (p <0.01). The results show that cardiac vagal outflow is attenuated and vasomotor sympathetic activity elevated during exciting sports events and BP dynamics differ from those occurring during physical exercise at equal HRs. The autonomic reactions may partly explain the vulnerability to cardiovascular events caused by this type of leisure-time emotional excitement. [Copyright &y& Elsevier]

Abstract: Attenuated cardiac vagal regulation indicates an increased risk of cardiac events, but the reasons for this impaired regulation are not well known. Cardiac vagal regulation was measured in 5.408 subjects (2627 men and 2781 women) who underwent short term (100s) ECG recordings during controlled deep respiration (0.1Hz). Under these conditions, the power in the low frequency (LF) spectral band (0.05 to 0.15Hz) predominantly reflects cardiac vagal outflow. There was a strong inverse relationship between LF power and age in both genders (β=−0.033 in men and −0.035 in women; P<0.0005). There was a more rapid decline in women in the second and third decade in which LF power was significantly lower than in men (P=0.004). In both genders, there was an association between impaired cardiac vagal outflow and fibrinogen level. Altogether, the factors studied explained nearly 20% of the interindividual variation of LF power. In conclusion, in a general population, impaired cardiac vagal regulation is associated with many cardiovascular risk factors, including fibrinogen. Women have a more rapid decline of vagal regulation in the second and third decades. [Copyright &y& Elsevier]

Type 2 diabetes (T2D) has shown limited impact on cardiac autonomic function in patients with cardiac disease at rest. The effect of T2D on autonomic responses to sympathetic stimuli, such as passive tilt and static exercise, is not well known in patients with coronary artery disease (CAD). Heart rate, arterial pressure, and their variability along with baroreflex sensitivity (BRS) were analyzed at supine rest and during passive head-up tilt (TILT) and static handgrip exercise (HG) in CAD patients with (T2D+, n=68, 61±6years, 14 women) and without T2D (T2D−, n=68, 62±6years, 17 women). The effect of T2D at rest and in responses to TILT and HG was examined. In T2D+, the normalized low-frequency (0.04–0.15Hz) power of R–R intervals was higher at rest (44±17 vs. 38±17nu, p=0.015) and its response to TILT and HG was lower than that in T2D− (8±21 vs. 2±17nu, p=0.041 and 3±18 vs. −4±15nu, p=0.019, respectively). Vagally mediated heart rate variability indices and BRS were not different between T2D+ and T2D−. We concluded that T2D has a specific impact on low-frequency oscillation of R–R interval among patients with angiographically documented CAD. This may indicate increased basal sympathetic modulation of sinoatrial node and lower sympathetic responsiveness to sympathetic activation by baroreceptor unloading and exercise pressor response. Limited effects of T2D on vagally mediated heart rate variability and baroreflex were observed in the patients with CAD. [ABSTRACT FROM AUTHOR]

Abstract: Emotional excitement may trigger cardiovascular (CV) events, particularly in patients with coronary artery disease (CAD). Our aim was to compare changes in various biomarkers in CAD patients and age-matched healthy male subjects during “real-life” emotional excitement. Enthusiastic male ice hockey spectators (CAD n=18, healthy subjects n=16) attended Finnish national ice hockey play-off matches. Heart rate variability, plasma catecholamines, endothelin-1 (ET-1) and interleukin-6 (IL-6) were determined at the baseline and during the match. A significantly more marked increase in both ET-1 and IL-6 was observed in CAD patients compared with healthy subjects during the match (time×group interaction p=0.009 and p=0.018 for ET-1 and IL-6, respectively). The high-frequency power of R–R intervals decreased in CAD patients (p<0.001) but did not change in healthy subjects (p=ns, time×group interaction p<0.001). Changes in adrenaline and noradrenaline did not differ between the groups. Emotional excitement causes more marked increases of markers of vasoconstriction and acute inflammation and withdrawal of cardiac vagal regulation in patients with CAD. [Copyright &y& Elsevier]

Abstract: Cardiovascular autonomic dysfunction, which is a common complication of diabetes, is associated with increased mortality in patients with coronary artery disease (CAD). However, the reasons of autonomic dysfunction in CAD patients with or without diabetes are not well known. We examine the association between heart rate recovery (HRR) and other potential factors among CAD patients with and without type 2 diabetes (T2D). Correlations between HRR 60s after exercise (HRR60), characteristics, laboratory and echocardiographic variables, exercise capacity and physical activity were assessed in 50 CAD patients with T2D and 55 patients with CAD alone. HRR60 had the closest univariate correlation with physical activity and exercise capacity in patients with T2D (r=0.38, p=0.006 and r=0.37, p=0.008, respectively). Age, exercise capacity and high-density lipoprotein cholesterol level explained 30% of the HRR60 in patients with T2D (p=0.001), while the high intensity physical activity was the only predictor of HRR60 in CAD patients (12%, p=0.010). HRR60 was reduced in patients with T2D as compared with those without (34±9 vs. 39±9bpm, p=0.005), but the difference was no longer significant after adjustments for physical activity, exercise capacity, body mass index and the use of calcium antagonists and nitrates (p=0.273). In conclusion, blunted HRR is more common among CAD patients with T2D than in those without, and this is more closely related to physical activity and obesity than to the duration of T2D or associated co-morbidities. [Copyright &y& Elsevier]

Abstract: The purpose of this study was to assess the power and the frequency of low-frequency (LF; 0.04–<0.15Hz) oscillations in systolic blood pressure (SBP) and R–R interval (RRi) across the continuum of risk of cardiovascular disease, including age. A potential confound in such determinations is low spontaneous breathing frequency in some individuals. We measured beat-to-beat SBP, RRi and respiration in healthy YOUNG (33±3years) and OLDER subjects (62±5years) and older patients with hypertension (HT, 61±5years), coronary artery disease without (CAD, 62±5years) and with type 2 diabetes (CAD+DM, 62±4years, n =28 for all groups) during spontaneous breathing at supine rest. Power (PowerLF) and median frequency (MedLF) of LF oscillations were calculated by power spectral analysis after removing respiratory effects by least-mean-square adaptive filtering. OLDER had higher PowerLF-SBP (5.5±3.0 vs. 3.4±2.5mmHg2, p =0.002) and lower PowerLF-RRi than YOUNG (339±460 vs. 575±422ms2, p =0.001) whereas neither variable differed between OLDER and patient groups. MedLF-SBP (0.072±0.009 vs. 0.080±0.011Hz, p =0.005) and MedLF-RRi (0.072±0.010 vs. 0.079±0.013Hz, p =0.027) were lower in OLDER compared with YOUNG. Compared with OLDER, MedLF-RRi was lower in CAD (0.065±0.006Hz, p =0.015) and CAD +DM (0.066±0.008Hz, p =0.012); whereas CAD+DM had also lower MedLF-SBP (0.065±0.006Hz, p =0.012). No differences were observed between OLDER and HT and between CAD and CAD+DM in these variables. We concluded that age is major determinant of the power of LF oscillations in SBP and RRi at rest, whereas the median frequency of these oscillations is altered also by coronary artery disease. [Copyright &y& Elsevier]

Abstract: Altered frequency of slow (0.04–0.15Hz) arterial pressure and R–R interval oscillations has been observed in various diseases but the mechanisms for this frequency shift are unclear. The median (Med) frequencies of slow R–R interval and blood pressure (BP) oscillations were recorded in 11 healthy subjects with paced breathing (0.25Hz) during muscle metaboreflex and baroreflex mediated sympathetic stimuli: 1) handgrip exercise (HG) followed by post-exercise circulatory occlusion (PECO), 2) handgrip exercise during ischemia by circulatory occlusion (IHG) and 3) passive head-up tilt (TILT). MedBP shifted to the higher frequency during HG, PECO and IHG (from 0.070±0.009Hz to 0.088±0.013, 0.085±0.015 and 0.099±0.013Hz, respectively, p <0.01 for all) but not during TILT (0.078±0.012Hz). Similarly, MedR–R shifted to the higher frequency during HG, PECO and IHG (from 0.072±0.009Hz to 0.085±0.014, 0.085±0.016 and 0.095±0.015Hz, respectively, p <0.01 for all) but not during TILT (0.075±0.012Hz). MedBP and MedR–R were higher during IHG compared to HG and lower during TILT compared to both HG and IHG (p <0.01 for all). We conclude that the sympathetic stimulus induced by muscle metaboreflex is an important mechanism increasing the frequency of slow oscillations in arterial pressure and R–R intervals. The present results give new insight to understand the physiology underlying the frequency of slow arterial pressure and R–R interval oscillations. [Copyright &y& Elsevier]