Stolen Rhythms – how a pianist made music from her ECGs

Guest post by Elaine Chew

As a child, having supra-ventricular tachycardia meant that, due to extra electrical pathways in my heart, a simple trigger such as an early heartbeat could double my heart rate at any time. The early beat is often hard to feel, but the delayed beat that follows was unmistakeable—a big thump! that would jump start the doppio movimento. (For an example of doppio movimento, Professor John Rink has kindly suggested the beginning of Chopin’s Piano Sonata No. 2 in B-flat minor, Op. 35; see a performance by Ivo Pogerelich.) Another thump would end the tachycardia episode as abruptly as it began, which was as likely to be three seconds, thirty minutes, or three hours later.

Doubling the heart rate is fine and good when one is at rest, say seated and reading; twice 60 beats per minute (bpm) would only be 120 bpm, still within a normal range. But rate doubling can be problematic when exercising, like when swimming, where doubling the heart rate of 120 bpm results in a breathless 240 beats per minute and seeing stars if standing upright, the only recourse at this point being lying horizontal and waiting for the episode to pass.

This non-deadly but troublesome arrhythmia was cured through a minimally invasive procedure called radio frequency ablation, which burns the dysfunctional tissue in the heart. The scar tissue that forms can no longer conduct electricity, and the circuit is thus broken. For a long time afterwards, every skipped heartbeat would still cause my muscles to tense and my breathing to pause in anticipation of tachycardia that never materialised, making me realise how unconsciously arrhythmia had impacted my life. I was thus blissfully arrhythmia free until atrial fibrillation hit.

The rhythms of tachycardia were rapid and regular, but atrial fibrillation was irregular in both musical rhythm and pacing. It is also associated with increased risks of mortality if allowed to progress unchecked. My heart started making its own funky rhythms like the following:

which was meticulously transcribed from the inter-beat intervals in the electrocardiogram (ECG) recording from a Holter monitor:

This is not unlike the kinds of rhythms musicians are used to reading. A minor adjustment to the well-known Siciliano, the middle movement from the Flute Sonata in E-flat major (BWV 1031) by J. S. Bach, readily produces an exact fit to the transcribed rhythm:

See the video with audio playback of the modified Bach Siciliano. Readers interested in the gnarly details of the transcription process and its precision can refer to this Music & Science article on notating temporal deviations in music and arrhythmia.

AF is a fast growing global epidemic; statistics show that the condition afflicts over two million people in the UK alone. The inefficient blood flow through the heart in AF increases the risk of blood clots that can lead to stroke. Many people with AF are unaware that they have the condition, but I was amongst those doctors euphemistically describe as very symptomatic. Another ablation procedure—this time with freezing balloons (cryo-ablation)—created barriers in my heart, rings of scar tissue around the pulmonary veins, to contain the errant electrical activity, thus curing the condition.

When the consultant cardiologist came by the ward to ask if I had any questions, I asked for ECG data that I could use for musical analysis and experimentation. This has led to a number of computational projects, mostly scientific in nature, but the first of these was a growing set of piano pieces called the Arrhythmia Suite. With the help of three research partners at the Radcliffe Institute for Advanced Study at Harvard, the inter-beat durations were extracted from the ECG traces and the rhythms carefully transcribed. I then cannibalised existing music to make collage pieces based on these rhythms. See the video on the making of the Arrhythmia Suite. When performed, the pieces make visceral the rhythmic experience of arrhythmia.

On Tuesday, 20 November 2018, at 1pm, I will perform these pieces in Heart & Music at the Octagon (Queen’s Building, 327 Mile End Road, London E1 4NS) at Queen Mary University of London, as part of the Being Human Festival. The concert programme will feature music made from stolen rhythms, including the ones taken from ECG traces of cardiac arrhythmias. Professor Pier Lambiase, the consultant cardiologist who led the clinical team on both ablation procedures, will give a short introduction to arrhythmia research at the Barts Heart Centre before the performance. Admissions to Heart & Music, which kicks off the all-day Keyboard Evolutions event is free, but booking is recommended.

Other pieces on the recital programme include Cheryl Frances-Hoad’s Haydn’s Stolen Rhythm (2009), in which the composer assigns new pitches to the third movement (Finale) of Haydn’s Sonata in E-flat, Hob XVI:45, keeping intact Haydn’s original rhythms; Practicing Haydn (2013) is a transcription of my sight-reading of the same Haydn sonata movement complete with hesitations and repetitions—this was a collaboration with composer Peter Child and conceptual artist Lina Viste Grønli that premiered at the grand opening of the Kunsthall Stavanger; Intermezzo (2015) was written by Jonathan Berger for pianist Pedja Muzijevic’s Haydn Dialogues; and, compositions based on J. S. Bach’s A Little Notebook for Anna Magdalena and Kabelevsky’s 30 and 24 Pieces for Children (2016) were created by a computer programme called MorpheuS, written by Dorien Herremans as part of her Marie Skłodowska-Curie Fellowship in my lab.

Following the concert, at 2:30pm, an interactive workshop will enable free-form Q&A with Profs. Lambiase, Peter Taggart, and myself on the preceding presentations as well as our ongoing study on cardiac response to live music performance. Abnormal heart rhythms can often be linked to strong emotions or mental stress. Because music is a powerful idiom through which to evoke strong emotions, this study uses music to induce mild tension in patient volunteers with biventricular pacemakers or ICDs to better understand the connections between emotion response and heart rhythms.


Elaine Chew is Professor of Digital Media at Queen Mary University of London, where she is affiliated with the Centre for Digital Music. She is recent recipient of a European Research Council Advanced Grant for the project COSMOS: Computational Shaping and Modeling of Musical Structures, which will start in January 2019. COSMOS aims to study musical structures as they are created in performance and in recordings of cardiac arrhythmias.

About COSMOS — https://erc-adg-cosmos.blogspot.com

About Elaine’s research — https://elainechew-research.blogspot.com

About Elaine’s piano activities — https://elainechew-piano.blogspot.com

About the Music, Performance and Expressivity lab — https://mupae.blogspot.com