Tuning the heart with music

Along with ice cream, chocolate and romantic comedies, music has often been used as a traditional remedy for a broken heart¹ but could there be any truth behind this?

Music and medicine were once two arts that performed in unison. In ancient Greece, Apollo is the God of both music and medicine,² in Chinese the character for medicine includes the character for music³ and in the Old Testament young David is said to have played the Lyre for King Saul as a method of healing and by doing so, is frequently considered the first music therapist.⁴ Though, as technology advanced and our knowledge expanded, scientific approaches such as causality and evidence-based practice dominated gradually breaking the connection of medicine and music in Western medicine. However, recently, researchers have turned their attention to the effects of music on the cardiovascular system, and the results illustrating the strength of their connection and its validity as a form of treatment are surprising.

A single beat of a heart (‘lub dub’) can be translated into musical terminology as a duple with a dotted rhythm. A study has shown that this innate cardiovascular rhythm can be synchronised with specific external rhythms found in music, such as the phrase of six cycles per minute seen in well-known arias by Verdi.⁵ The observed synchronisation between the music and cardiovascular system occurred independently of any respiratory modulation and suggests that music therapists could directly synchronise the cardiovascular beat with music.⁶ There is no concrete scientific explanation for this, though by mere speculation it is thought that there is more of a neural rather than humoral component to this mechanism due to the fast response of the cardiovascular system to the music.⁷ Perhaps Verdi had an inkling that this was possible as a lyric to one aria composed by him is: ‘… delight to the heart’.

Moreover, in cardiology wards, patients can sometimes feel a decreased sense of control over their body coupled with the unfamiliar sounds of machines it can lead to anxiety and unsurprisingly, this is often the case with those undergoing cardiac surgery.⁸ An increased level of anxiety is not to be taken lightly as it can have negative physiological effects on the heart and can lead to a greater risk of complications.⁹ Elevated cortisol and adrenaline in the bloodstream caused by anxiety can increase heart rate, blood pressure and the release of fatty acids into the bloodstream, all of which decrease the prognosis of cardiac patients.¹⁰ Music therapy is a possible solution for this. A study used the physiological markers of blood pressure and respiratory rate to demonstrate that listening to music decreased levels of anxiety in patients and was in fact a more effective method of anxiety reduction compared to uninterrupted rest periods.¹¹ Despite the fact that listening to music seems to be a simple and inexpensive method of possibly increasing patient prognosis, it is rarely used. A theory regarding this anxiety-reducing effect of music is that music can assist in focusing the patient’s attention away from perhaps the uncomfortable hospital surroundings to an aesthetic experience that provides comfort.¹² Additionally, it is believed that music’s anxiolytic effect is achieved through its suppressive action of the sympathetic nervous system, leading to decreased adrenergic activity.⁸ However, evidence for the physiological mechanisms of musical therapy are still in their early stages and are only now beginning to emerge.

Furthermore, Zengin et al. looked at port catheter placement procedures and found that music therapy could reduce the patient’s perception of pain. Invasive medical procedures are known to have a negative impact on patients, causing emotional distress and anxiety, which may result in more pain and discomfort.¹³ Often an array of sedative drugs is used to decrease the patient’s perception of pain but frequently these drugs can exhibit side effects. Zengin et al. found that patients who listened to music reported lower levels of pain.¹³ A possible scientific explanation for this is that music provides competing stimuli for the impulses relating to pain; therefore, less pain is processed by the brain via the spinal cord.¹⁴ However, there is some controversy over whether music therapy has any effect on the perception of pain.¹⁵ It is not surprising that there are contradictory results surrounding music therapy. There are a huge amount of variables with regard to music: genre, amplitude, beat and lyrics to name a few. Each music clip could cause the patient to react in a different way, causing inconsistencies between different studies. Additionally, a study has shown that patients who play a musical instrument demonstrate higher cardiovascular modulation induced by music. This may have altered study results if not taken into consideration.¹⁶ Finally, music is not a single event, but is an ongoing stimulus that changes in real time and over time, resulting in corresponding changes in the response of the person experiencing it. Therefore, the impact of listening to one piece of music is contingent on more variables than could possibly be controlled in a scientific experiment adding to variability in results.¹⁷

Looking at music therapy from a broader perspective, evidence suggests that music therapy can also reduce recovery time in other diseases. In stroke patients, it was found that after a two-month intervention period, patients who listened to their favourite music for 1–2 h a day showed greater improvement in focused attention and verbal memory than patients who listened to audio books or received no listening material.¹⁸ Patients were also less depressed and confused. The speculated mechanism behind this is that listening to pleasant music activates an interconnecting network of subcortical and cortical regions; this includes the ventral tegmental area.¹⁸ The ventral tegmental area produces dopamine and has direct projections to the nucleus accumbens. This connection is associated with the suppression of adverse stimuli and pain, which could lead to the beneficial effect of patients feeling less depressed.¹⁸ In other areas of medicine, patients with chronic obstructive pulmonary disease have shown less dyspnoea on exertion when listening to music as the auditory stimuli provide distraction from their fatigue and shortness of breath¹⁹ and in Parkinson’s disease, music therapy has proved to improve rhythmic limb movement, gait and freezing.²⁰

However, aiming for optimal cardiac benefits, make no mistake – music therapy does not claim to clear blocked arteries or prevent heart attacks; its aim is to be used alongside conventional cardiac interventions to help treat and reduce recovery times. As opposed to modern day medicines, music therapy has no known side effects and therefore, any benefit derived from its use is advantageous. Research into its beneficial effects on the cardiovascular system is only just beginning to emerge and perhaps in the near future, young David’s method of healing could work alongside 21st century conventional treatments to alter aspects of current clinical practice. Until then, encouraging our patients (and staff) to enjoy music both inside and outside the hospital seems to be a good first step.

Declarations

Competing interests

None declared

Funding

None declared

Ethical approval

Not required

Guarantor

VV

Contributorship

All authors contributed equally in the concept and writing of the article.

Acknowledgements

None

Provenance

Not commissioned; editorial review