Objective: To assess the potential clinical use, particularly in modulating stress, of changes in the cardiovascular and respiratory systems induced by music, specifically tempo, rhythm, melodic structure, pause, individual preference, habituation, order effect of presentation, and previous musical training. Design: Measurement of cardiovascular and respiratory variables while patients listened to music. Setting: University research laboratory for the study of cardiorespiratory autonomic function. Patients: 12 practising musicians and 12 age matched controls. Interventions: After a five minute baseline, presentation in random order of six different music styles (first for a two minute, then for a four minute track), with a randomly inserted two minute pause, in either sequence. Main outcome measures: Breathing rate, ventilation, carbon dioxide, RR interval, blood pressure, midcerebral artery flow velocity, and baroreflex. Results: Ventilation, blood pressure, and heart rate increased and mid-cerebral artery flow velocity and baroreflex decreased with faster tempi and simpler rhythmic structures compared with baseline. No habituation effect was seen. The pause reduced heart rate, blood pressure, and minute ventilation, even below baseline. An order effect independent of style was evident for mid-cerebral artery flow velocity, indicating a progressive reduction with exposure to music, independent of style. Musicians had greater respiratory sensitivity to the music tempo than did non-musicians. Conclusions: Music induces an arousal effect, predominantly related to the tempo. Slow or meditative music can induce a relaxing effect; relaxation is particularly evident during a pause. Music, especially in trained subjects, may first concentrate attention during faster rhythms, then induce relaxation during pauses or slower rhythms.M usic now has an increasing role in several disparate areas. Music can reduce stress and improve athletic performance, motor function in neurologically impaired patients with stroke or parkinsonism, or milk production in cattle.

Abstract-Sympathetic hyperactivity and parasympathetic withdrawal may cause and sustain hypertension. This autonomic imbalance is in turn related to a reduced or reset arterial baroreflex sensitivity and chemoreflex-induced hyperventilation. Slow breathing at 6 breaths/min increases baroreflex sensitivity and reduces sympathetic activity and chemoreflex activation, suggesting a potentially beneficial effect in hypertension. We tested whether slow breathing was capable of modifying blood pressure in hypertensive and control subjects and improving baroreflex sensitivity. Continuous noninvasive blood pressure, RR interval, respiration, and end-tidal CO 2 (CO 2 -et) were monitored in 20 subjects with essential hypertension (56.4Ϯ1.9 years) and in 26 controls (52.3Ϯ1.4 years) in sitting position during spontaneous breathing and controlled breathing at slower (6/min) and faster (15/min) breathing rate. Baroreflex sensitivity was measured by autoregressive spectral analysis and "alpha angle" method. Key Words: baroreceptors Ⅲ blood pressure Ⅲ heart rate Ⅲ hypertension Ⅲ nervous system, autonomic Ⅲ respiration A utonomic imbalance has a major role in the etiology of hypertension. 1-4 Such imbalance, characterized by an increase in sympathetic activity (with a possible reduction in parasympathetic activity), is present not only in early and borderline hypertension but also contributes to the maintenance of sustained hypertension. 2 Moreover, several cardiovascular risk factors frequently associated with hypertension are etiologically linked to sympathetic activation. 2,5 At least one of the mechanisms associated with this autonomic imbalance is the reduced baroreflex sensitivity. The baroreflex is reduced or reset toward elevated blood pressure values in hypertension, blunting its ability to suppress the increased sympathetic activity. 6 An impairment of the baroreflex has a direct relation to increased 24-hour blood pressure variability, which in turn correlates with the increase in target-organ damage. 7 Furthermore, there are reports indicating a chemoreflex activation in essential hypertension, which can be an additional mechanism responsible for the increase in sympathetic activity. 8 Given the clinical and prognostic value of reducing sympathetic activation and increasing baroreflex sensitivity in hypertension, it is interesting to note that slow breathing at 6 cycles/min increases baroreflex sensitivity in normal subjects and patients with chronic heart failure 9,10 and also reduces muscle nerve sympathetic activity 11 and chemoreflex activation, 12 thus suggesting a potentially beneficial effect in hypertension. However, there is little evidence about the effect of slow breathing on arterial baroreflex in hypertensive patients, although a few recent studies have shown that device-guided breathing exercise may reduce blood pressure in hypertensive patients. 13 This study aims to test whether slow breathing at 6 cycles/min reduces blood pressure in hypertensive and normal subjects, and if this effect is linked to a...

Background — It is well established that a depressed baroreflex sensitivity may adversely influence the prognosis in patients with chronic heart failure (CHF) and in those with previous myocardial infarction. Methods and Results — We tested whether a slow breathing rate (6 breaths/min) could modify the baroreflex sensitivity in 81 patients with stable (2 weeks) CHF (age, 58±1 years; NYHA classes I [6 patients], II [33], III [27], and IV [15]) and in 21 controls. Slow breathing induced highly significant increases in baroreflex sensitivity, both in controls (from 9.4±0.7 to 13.8±1.0 ms/mm Hg, P <0.0025) and in CHF patients (from 5.0±0.3 to 6.1±0.5 ms/mm Hg, P <0.0025), which correlated with the value obtained during spontaneous breathing ( r =+0.202, P =0.047). In addition, systolic and diastolic blood pressure decreased in CHF patients (systolic, from 117±3 to 110±4 mm Hg, P =0.009; diastolic, from 62±1 to 59±1 mm Hg, P =0.02). Conclusions — These data suggest that in patients with CHF, slow breathing, in addition to improving oxygen saturation and exercise tolerance as has been previously shown, may be beneficial by increasing baroreflex sensitivity.