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Blood pressure response to head-up tilt (HUT) in 7 healthy subjects and 9 patients before and after coronary artery bypass grafting (CABG) was measured during supine and 15-min 60[degrees] HUT. Stroke volume (SV) and ejection fraction (EF) were assessed by echocardiography. Baseline mean arterial pressure (MAP) and heart rate (HR) in patients before CABG were similar to healthy subjects. MAP in patients decreased by 6 (4-9) mmHg [median (1st-3rd quartiles)] during 7-12 mmHg of HUT with decreased cardiac output (CO = SV x HR) while HR remained unchanged. MAP in healthy subjects remained unchanged during HUT with increased HR. Body weight decreased by 3.5 (2.5-3.7) kg and MAP decreased by 6 (2-13) mmHg during the last 3-min HUT while HR increased after CABG. Decreases in SV and CO during HUT disappeared after CABG. Blood pressure decreased during HUT in patients before and after CABG regardless of HR response. Keywords: Body fluid, Myocardial infarction, Angina pectoris, Rehabilitation, Author(s): Shinnosuke Hori[sup.1], Yoshi-ichiro Kamijo[sup.1], Mitsuru Yuzaki[sup.2], Tetsuya Kawabe[sup.3], Kohei Minami[sup.1], Yasunori Umemoto[sup.1], Mao Yokoyama[sup.4], Hiroyasu Uenishi[sup.1], Yoshiharu Nishimura[sup.2], Ken Kouda[sup.1], Yukio Mikami[sup.1] and Fumihiro Tajima[sup.1] Introduction Coronary artery bypass [...]

Cardiopulmonary function is usually assessed by cardiopulmonary exercise testing (CPX) using a cycle ergometer (CE-CPX) or a treadmill, which is difficult in patients with lower extremity motor dysfunction. A stepping and handshaking (SHS) exercise has been developed that can be performed safely and easily while sitting on a chair. This study compared peak oxygen uptake (peak V. O 2 ) between CE-CPX and SHS-CPX in healthy adults and investigated the safety and validity of SHS-CPX. Twenty young adults (mean age 27.8 ± 4.4 years) were randomly assigned to perform CE-CPX or SHS-CPX, with the other test to follow 1–2 weeks later. The peak V. O 2 , respiratory exchange ratio (RER), peak heart rate, blood pressure, and test completion time were compared between CE-CPX and SHS-CPX. All subjects completed the examination and met the criteria for peak V. O 2 . SHS-CPX and CE-CPX showed a strong correlation with peak V. O 2 (r = 0.85, p < 0.0001). The peak V. O 2 (40.4 ± 11.3 mL/min/kg vs. 28.9 ± 8.0 mL/min/kg), peak heart rate (190.6 ± 8.9 bpm vs. 172.1 ± 12.6 bpm), and test completion time (1052.8 ± 143.7 s vs. 609.1 ± 96.2 s) were significantly lower in the SHS-CPX (p < 0.0001). There were no adverse events. The peak V. O 2 with SHS-CPX was equivalent to about 70% of that with CE-CPX despite the exercise being performed in a sitting position, suggesting its suitability as a submaximal exercise test. [ABSTRACT FROM AUTHOR]

Objective: The aim of the present study was to compare the effects of acupuncture treatment on arterial blood pressure (BP) and heart rate (HR) in patients with mild hypertension with high sympathetic tone with those of normotensive patients and to examine the effects on cardiac sympathetic nerve activity (CSNA) and vagal activity using heart rate variability (HRV) analysis. Design: Eight male patients with prehypertension or stage I hypertension and eight normotensive age-matched patients were included in this study. All patients had their systolic BP (SBP), diastolic BP (DBP), HR, and HRV measured. In addition, the ratio of low-frequency (LF) to high-frequency (HF) HRV and the power of the HF of the HRV were recorded. The study was conducted at Kansai University of Health Sciences in Japan. Interventions: Each patient underwent a single, 15-min-long acupuncture session. Acupuncture was applied to PC6, LI4, ST36, LR3 on both sides, and GV20. Results: SBP and HR decreased significantly in the hypertensive group during and after acupuncture compared with the baseline SBP and HR (p < 0.05). LF/HF was significantly reduced during acupuncture (p < 0.05), and HF was significantly increased after acupuncture in the hypertensive group (p < 0.05). However, there were no significant changes in LF/HF or HF in the control group. Conclusions: Acupuncture may reduce the BP and HR in patients with mild hypertension. An HRV analysis suggests that acupuncture may suppress the enhanced basal CSNA activity and increase the vagal nerve activity in patients with mild hypertension. Clinical Trial Registration number: UMIN000041249. [ABSTRACT FROM AUTHOR]

Purpose: While non-noxious local cooling is widely used in physical medicine, its effect on muscle sympathetic nerve activity (MSNA) and cardiovascular regulation are not clear. The purpose of the present study was to assess the responses of MSNA, blood pressure (BP), heart rate (HR) and local blood flow during non-noxious local cooling.Methods: The study included two protocols. Both protocols consisted of 10-min rest in supine position, followed by 15-min local cooling (15 °C) of the shin and anterior foot, and 20-min recovery. MSNA of the right common peroneal nerve, BP, HR, and shin skin temperature (TSK) were recorded in eight men in the first protocol, while leg blood flow (LBF) was measured in the same subjects by strain-gauge plethysmography in the second protocol.Results: TSK gradually decreased from 31.5 ± 0.02 to 16.0 ± 1.01 °C (mean ± SEM) during local cooling, and gradually increased after the end of local cooling. No subject complained of pain, and BP and HR remained constant. The MSNA burst rate increased significantly (p < 0.05) to 141.1 ± 12.5 % during local cooling, but decreased significantly (p < 0.05) to 73.6 ± 5.9 % during the recovery period. Total MSNA also increased to 148.0 ± 14.2 % (p < 0.05) during local cooling, and decreased to 74.0 ± 13.9 % (p < 0.05) at recovery. LBF remained constant through the experiment.Conclusions: The results suggest that MSNA is activated by non-noxious local cooling, and attenuated after the end of local cooling without any changes in HR and BP. [ABSTRACT FROM AUTHOR]

Isometric muscle contraction (static exercise) induces circulatory response. Static exercise in individuals with thoracic spinal cord injury (TSCI) induces cardiovascular response and blood redistribution to the non-exercising muscles. The aim of our study was to determine the circulatory response during arm static exercise in individuals with TSCI and able-bodied (AB) controls. Mean blood pressure (MBP), heart rate (HR), cardiac output (CO), leg skin blood flow (SBF), and leg muscle blood flow (MBF) were recorded noninvasively, total peripheral resistance (TPR) was estimated by dividing MBP by CO, and hormonal changes were measured before, during and after static 35% maximal voluntary contraction (MVC) of the arm flexor muscles in seven male individuals with TSCI (T7-T11) and seven age-comparable AB control (32.2 ± 7.6 and 31.0 ± 4.7 years, respectively). The 35% MVC was similar in TSCI and AB individuals (107.3 ± 28.2 and 101.0 ± 22.5 N, respectively). HR, CO, MBP, TPR, SBF and MBF increased in both groups during arm static exercise. Plasma epinephrine concentration increased during arm static exercise in AB controls only ( P < 0.05). Circulation to leg muscles was similar in TSCI and AB individuals and the lack of sympathetic vasoconstriction in the paralyzed leg area did not alter the cardiovascular responses during 35% MVC of arm static exercise. We conclude that sympathetic vasoconstriction in the resting leg area did not contribute to the pressor reflex during 35% MVC of arm static exercise. [ABSTRACT FROM AUTHOR]

The study was designed to assess the effects of local heat (LH) application on postganglionic muscle sympathetic nerve activity (MSNA) measured by microneurography in healthy men. In the first protocol, MSNA of the left peroneal nerve, blood pressure (BP), heart rate (HR), and skin temperature of the shin (TSK) were recorded in nine men. In the second protocol, leg blood flow (LBF) was measured in the same subjects by strain-gauge plethysmography. In both protocols, after 10 min of rest in the supine position, a heated hydrocollator pack was applied to the shin and anterior foot for 15 min and recovery was monitored over a period of 20 min. TSK gradually increased from 31.7 ± 0.1 to 41.9 ± 0.5°C (mean ± SEM) during LH. No subject complained of pain, and BP and HR remained constant. The MSNA burst rate (16.1 ± 2.1 beats/min) during the control period decreased significantly (P < 0.05) to 72.0 ± 2.3% during LH. Total MSNA also decreased to 59.2 ± 2.6% (P < 0.05) during LH, but both immediately returned to baseline at recovery. In contrast, LBF in the left leg significantly and immediately increased (P < 0.05) after LH application and remained significantly elevated until the end of the recovery period. These results suggest that: (1) LH application significantly attenuates MSNA without any changes in HR and BP. (2) Other factors in addition to MSNA seem to control regional blood flow in the lower extremity during LH. [ABSTRACT FROM AUTHOR]