The heart of the matter

Heart doctor Michael Henein steps back to consider the unseen and unique wonders of the human body’s design.

Michael Henein

Professor Michael Henein is a consultant cardiologist, and a Professor of Cardiology at Umea University, Sweden.

A model of a human heart on a short stand.

Photo by Jesse Orrico on Unsplash.

Shakespeare famously asked:

“What a piece of work is a man, how noble in reason, how
infinite in faculties, in form and moving how express and admirable, in action how like an angel, in apprehension how like a god! the beauty of the world, the paragon of animals—and yet, to me, what is this quintessence of dust?

Humans may be complex, capable of great heroism and deep depravity, yet it is worth stopping for a moment to look at the human body and mind to marvel in what we have become, and how we are made.

The visible design of the human body points out common features shared along with other members of the animal kingdom. Examples of these features are: two eyes, two ears, two nostrils, one mouth and four limbs, attached to a body and head. Detailed study of different seen parts of the body may, however, show some differences. For example, the presence of fingers and nails, hair distribution as well as a developed tail. While most members of the animal kingdom have teeth and a tongue, those two could also vary in their number and size, respectively, according to different species. Genetic investigations have shown that we humans share 99 % of our genes with animals, suggesting that our “earthly” component shares a common origin. Indeed, the twenty first century scientific findings match what is written in the Genesis story of creation, a story written over 3,500 years ago, well before genetic sciences came to light.

Creatures great and small

As for morphological differences between animal species, it is difficult to naively conclude why some are wild while others are man-friendly-even if the wild ones have different shapes, design, dietary habits, body size and life span. Other important observed features of the members of the animal kingdom are that they are all born, they all age, then ultimately die.

If we are to look at the unseen features of the members of the animal kingdom, we can again identify similarities. For example, all have a gastrointestinal tract, a cardiovascular system, a reproductive system, a respiratory system, a urinary system and much more. While these systems may differ slightly between species, the overall structure and function achieve similar purposes. For example, heart speed is faster in small animals like rats compared to big ones like elephants who have very slow hearts. Likewise, the respiratory system and the number of respiratory cycles per minute are significantly faster in running animals compared to the sedentary and slowly moving ones. Finally, the number of offspring also differs in different species, being just one at a time in big animals like elephants and horses, and many offspring in small animals like rabbits and mice. Such paradox between the number of offspring and animal size makes you think of the important determining role of the activity of those animals.

Unseen wonders

Now to turn to the rest of the animal kingdom and the unseen features of the human body. To start, let us look at the amazing functions of the human brain and its various functions. When humanity is sometimes described as the crown of creation, such a description is based on the superiority of human brain function and skills. Its sophisticated structure and how vital centres are created deep in the skull, to be protected from traumas, make you marvel. Also, the brain controls the different functions of the whole body, with its sensory and motor activities, various vital system functions including the lungs and the heart, all endocrine glands’ function, in addition to various receptors and centres that allow utmost precision and accuracy in everything we do. An example of this kind of precision is a doctor feeling a vein or an artery with the tip of a finger to insert a needle or a musician moving a finger a few millimetres while playing a violin, to produce the exact sound needed. Furthermore, the integrated function of human muscles, nerves and spinal cord is also amazing, let alone the synapsis between the nerve endings and muscle bundles, the chemicals secreted in them which allow electric stimulus transmission from the nervous system to achieve the motor function and desired movement.

The human brain also has the unique feature of storing knowledge. Of course, we should not ignore the importance of the training and programming ability of human brain. We learn how to drive a car, how to play games, how to study, how to operate safely on a sick patient. Such acquired skills are quite limited in other members of the animal kingdom. Moreover, the human brain has the unique ability to invent, discover, improve and correct errors it identifies.

Another very unique feature of human brain is its ability to conduct speech, a feature of humans that is under-developed in other members of the animal kingdom. While most animals can make noise and sounds, only humans can articulate words, sentences and even sing very complex songs. This unique ability seems to be the underlying mechanism behind the development of languages which are based on the human ability to talk and transmit information and knowledge by words and phrases.

The unseen brain has allowed human life to develop over time, building skills and achievements from generation to generation. Millennia ago, humans lived in huts together with animals, and now they build houses and palaces to live in. Centuries ago, we used donkeys, horses and camels to travel but now we use cars, trains, ships and airplanes. Our ancestors burned wood and coal to cook and to warm but now we use electricity to do these.

When we look carefully at the unseen parts of the human body, we also realize that we cannot alter any of it, despite the scientific advances made over the years. We can understand what harms our body and take measures to avoid it. Out of the ability of our brain to discover and invent, we have now produced science-based means for curing various diseases. Consider how we can replace a dysfunctional heart valve or a mobility-limiting joint. These inventions have resulted in a better quality of life, alleviating of symptoms, even helping to avoid early death, in some cases such as heart disease and cancer.

The heart of the matter

Another unseen source of life in humans is the heart. This fist-size organ is so complex in its structure and function. Recent scientific advances have enabled us to study heart function in milliseconds, hence the development of pacemaker treatments. They have also allowed clear imaging of the inside of the heart and the identification of pathologies, developments that guide practitioners to the optimum treatment of heart conditions. Recent discoveries have also allowed us to better understand how people develop coronary artery disease and how the pathology starts at the innermost layer of the arteries, particularly in individuals carrying significant risks for atherosclerosis including, smoking, high blood pressure, diabetes, high cholesterol and obesity. Amazingly, obesity has been shown to be the strongest underlying cause of other risk factors, hypertension, diabetes and hypercholesterolemia. So, nature cannot be blamed in many of these patients but our own patterns of behaviour. Science has shown that walking at least 5,000 steps each day, complying with the design of our body, reduces the likelihood of developing coronary artery disease by 15 per cent.

The unseen physiology of the rest of our body systems and the interaction between systems make us wonder how we are made. A rise of our body temperature by one degree due to a bug infection affects all body systems from the brain to the heart. A virus which cannot be seen by the most powerful microscope can destroy our lungs and cause premature death, as was the case with COVID-19 and others.

Finally, human inventions in the form of powerful microscopes have allowed scientists to study the human cell, which is the smallest living component of our body. Such small cells cannot be replicated in any factory in the twenty-first century, despite the vast scientific developments that surround us. You'll be surprised to learn how complicated and meticulously fine-tuned a human cell is and also how it functions, connects with other cells and other parts of the body. An example of this is the interaction between body minerals, calcium, sodium and potassium with heart and muscle individual cells. Such a function is critically controlled by many factors such as time, electric stimulation and pressure differences producing remarkably harmonious contractions and relaxation of the muscles without missing a beat.

Article

Assisted dying

Care

Comment

Politics

7 May 2025

4 min read

Assisted dying is not a medical procedure; it is a social one

Another vote, and an age-related amendment, highlight the complex community of care.

Henna Cundill

Henna is a researcher with the Centre for Autism and Theology at the University of Aberdeen.

Graffiti reads 'I miss me' with u crossed out under the 'mem'

Sidd Inban on Unsplash.

Scottish Parliament’s Assisted Dying bill will go to a stage one vote on Tuesday 13th May, with some amendments having been made in response to public and political consultation. This includes the age of eligibility, originally proposed as 16 years. In the new draft of the bill, those requesting assistance to die must be at least 18.

MSPs have been given a free vote on this bill, which means they can follow their consciences. Clearly, amongst those who support it, there is a hope that raising the age threshold will calm the troubled consciences of some who are threatening to oppose. When asked if this age amendment was a response to weakening support, The Times reports that one “seasoned parliamentarian” (unnamed) agreed, and commented:

“The age thing was always there to be traded, a tactical retreat.”

The callousness of this language chills me. Whilst it is well known that politics is more of an art than a science, there are moments when our parliamentarians literally hold matters of life and death in their hands. How can someone speak of such matters as if they are bargaining chips or military manoeuvres? But my discomfort aside, there is a certain truth in what this unnamed strategist says.

When Liam McArthur MSP was first proposed the bill, he already suggested that the age limit would be a point of debate, accepting that there were “persuasive” arguments for raising it to 18. Fortunately, McArthur’s language choices were more appropriate to the subject matter. “The rationale for opting for 16 was because of that being the age of capacity for making medical decisions,” he said, but at the same time he acknowledged that in other countries where similar assisted dying laws are already in operation, the age limit is typically 18.

McArthur correctly observes that at 16 years old young people are considered legally competent to consent to medical procedures without needing the permission of a parent or guardian. But surely there is a difference, at a fundamental level, between consenting to a medical procedure that is designed to improve or extend one’s life and consenting to a medical procedure that will end it?

Viewed philosophically, it would seem to me that Assisted Dying is actually not a medical procedure at all, but a social one. This claim is best illustrated by considering one of the key arguments given for protecting 16- and 17- year-olds from being allowed to make this decision, which is the risk of coercion. The adolescent brain is highly social; therefore, some argue, a young person might be particularly sensitive to the burden that their terminal illness is placing on loved ones. Or worse, socially motivated young people may be particularly vulnerable to pressure from exhausted care givers, applied subtly and behind closed doors.

Whilst 16- and 17- year-olds are considered to have legal capacity, guidance for medical staff already indicates that under 18s should be strongly advised to seek parent or guardian advice before consenting to any decision that would have major consequences. Nothing gets more major than consenting to die, but sadly, some observe, we cannot be sure that a parent or guardian’s advice in that moment will be always in the young person’s best interests. All of this discussion implies that we know we are not asking young people to make just a medical decision that impacts their own body, but a social one that impacts multiple people in their wider networks.

For me, this further raises the question of why 18 is even considered to be a suitable age threshold. If anything, the more ‘adult’ one gets, the more one realises one’s place in the world is part of a complex web of relationships with friends and family, in which one is not the centre. Typically, the more we grow up, the more we respect our parents, because we begin to learn that other people’s care of us has come at a cost to themselves. This is bound to affect how we feel about needing other people’s care in the case of disabling and degenerative illness. Could it even be argued that the risk of feeling socially pressured to end one’s life early actually increases with age? Indeed, there is as much concern about this bill leaving the elderly vulnerable to coercion as there is for young people, not to mention disabled adults. As MSP Pam Duncan-Glancey (a wheelchair-user) observes, “Many people with disabilities feel that they don’t get the right to live, never mind the right to die.”

There is just a fundamental flawed logic to equating Assisted Dying with a medical procedure; one is about the mode of one’s existence in this world, but the other is about the very fact of it. The more we grow, the more we learn that we exist in communities – communities in which sometimes we are the care giver and sometimes we are the cared for. The legalisation of Assisted Dying will impact our communities in ways which cannot be undone, but none of that is accounted for if Assisted Dying is construed as nothing more than a medical choice.

As our parliamentarians prepare to vote, I pray that they really will listen to their consciences. This is one of those moments when our elected leaders literally hold matters of life and death in their hands. Now is not the time for ‘tactical’ moves that might simply sweep the cared-for off of the table, like so many discarded bargaining chips. As MSPs consider making this very fundamental change to the way our communities in Scotland are constituted, they are not debating over the mode of the cared-for’s existence, they are debating their very right to it.