I recently completed a doctoral research project focused on using the philosophical approach of phenomenology – the study of experience and consciousness – to develop a framework to better understand what it might be like to live with an artificial heart.
This includes ways patients and carers’ lives will change but which don’t generally come up in informed consent or disclosure protocols, because they are not strictly “clinical”.
Artificial hearts?
Heart failure is a common disease in which a person’s heart is unable to pump enough blood to meet the requirements of their body. The gold standard treatment for end-stage heart failure is heart transplantation.
Increasingly, however, patients are offered artificial hearts as a bridge-to-transplant or a “destination therapy”. Artificial hearts supplement or replace the organic heart and perform the heart’s blood pumping function. While they can provide this life-saving function, artificial hearts also generate both obvious and subtle changes in their bearers’ lives.
One important distinction among artificial hearts is between:
- pulsatile devices, which mimic the rhythmic heartbeat of the organic heart; and
- continuous-flow designs, impel blood using a spinning rotor. These do not pulse or beat like organic hearts do.
The component which actually pumps blood is implanted within the patient’s chest. A driveline perforates the patient’s body and runs to a battery pack and a computer controller, both of which are carried around by the patient.
Phenomenology
The framework I developed is based in the work of philosophers like Edmund Husserl, William James, María Zambrano, and especially Maurice Merleau-Ponty. They all give reason to think that there is a connection between the body, and especially the heart, and our perception of time.
The framework has three major axes in which experience might change after receiving an artificial heart:
- Incorporation, or the patient’s sense of their own body and self;
- Motor intentionality, or how the patient relates to and can act in the world; and
- Temporality, or how the patient experiences time.
People often tell me that temporality is the least intuitive part. So, let’s start there.
Artificial hearts affect temporality at three distinct timescales: short-, medium-, and long-term.
Short-term
There is neuroscientific evidence that perception and emotional response to stimuli is influenced by heart rhythm. Changes to rhythm therefore influence experience.
In the case of artificial hearts which don’t pulse, there is the rather radical change of completely detaching a person’s bodily experience from the physiological pulse they are used to, and to which their temporality is calibrated.
Artificial hearts which do pulse introduce a new, alternative cardiac rhythm independent of the heart’s native electrophysiology. There is evidence that it can establish sort of rhythm which can dominate interoceptive input from the existing, endogenous heartbeat.
What a patient feels to be their native heartrate may be supplanted by an artificial rhythm received from an artificial heart device. And a patient’s bodily temporality may either be confused or replaced by a timing determined by technicians.
People can end up feeling “out of sync” with their own sense of time.
Medium-term
In the cases of lots of medical devices, and especially artificial hearts, device requirements end up determining the ways in which days can be structured.
The needs of the artificial heart device define the appearance and disappearance of windows of possibility. The possibility of eating at a restaurant or watching a film at a cinema is bounded by the time required for the activity and the availability of infrastructure, such as whether the patient can plug in to mains power.
These considerations, as well as alarms and battery displays on artificial heart controllers, introduce make explicit the ways devices are implicated in the habits and activities of patients.
Rather than a background condition of experience, time is crystallised, quantified and announced by the alarms in artificial heart devices and the body is made conscious of time as a tangible, vital resource.
Long-term
Artificial hearts are mostly employed as bridging devices. The are a midpoint along a therapeutic journey until an assessment and decision about heart transplantation is made.
And yet, given the significant gap between supply and demand for transplant hearts, transplantation often remains a distant hope rather than an immediate prospect. Even patients who expect to receive a transplant heart must find ways of living with their device in the meantime.
Patients and families develop ways of coping with an artificial heart which can eventually become habits. In the end, artificial heart habits can eclipse expectations of future interventions.
And as a result, patients may develop a preference for the present, and be motivated by fear, anxiety, and aversion to trauma to resist the future. This can keep the patient suspended within an expanded present which is disconnected from a therapeutic future.
Concluding thoughts
Temporality is fundamental to our lives. Artificial hearts have the potential to profoundly affect patients in ways which go beyond the clinical into the phenomenological, at multiple timescales.
As a result, artificial hearts deserve both attention and consideration by clinicians, designers, researchers, and patients.
About the author
Pat McConville
@ptmcconville
Pat McConville is a philosopher and bioethicist based in lutruwita Tasmania, Australia. He applies his expertise in phenomenology and experience as a patient with a single-ventricle heart to questions of health and illness. He has published on the topics of congenital illness, medical devices, research ethics, feminist bioethics and, for something completely different, video game aesthetics.
Feature image: Reinheart TAH