Throughout time, the human heart has been a source of wonder and fascination. Essential for sustaining life, the heart has also become a powerful symbol of romantic love and intense emotion across societies and cultures. Phrases like ‘my heart sank,’ and ‘I gave you my heart’ emphasize its prominence in language. 

But how did an internal organ come to represent life’s most nuanced emotions? What distinguishes the heart from other vital organs, like the liver and kidneys? And what happens when scientists, with good intentions, begin to probe something that many consider sacred? 

A tale as old as time: tracking the heart’s enduring power

Ancient humans first deciphered the heart’s significance through pulse-taking. In the Epic of Gilgamesh — one of the world’s oldest written works recorded 5,000 years ago in Mesopotamia — the hero, Gilgamesh, confirms the death of his friend by saying, “I touch his heart, but it does not beat at all.” 

The recognizable thud of the human heart provided a tangible and widely applicable form of medical diagnosis long before anatomical dissections became the norm. It was quickly established that a racing heartbeat corresponded with the intensity of activities; an accelerated heartbeat corresponded with intense activity, while a slowed heartbeat indicated a lack of it. Humans understand the heart’s importance through the pulse’s connection to a wide range of conditions, from chronic anxiety to breathing disorder sleep apnea, both medical issues marked by variations in pulse rhythm and speed. 

Yet, the heart’s influence extended beyond physiological curiosities. Transforming from a beacon of physical health to a representation of emotional connection, the refinement of the heart’s symbolism can be traced back to the early 1300s. In the Romance of Alexander, a medieval French manuscript adorned with colourful imagery, a woman is depicted holding the heart of a man who sits before her. He touches his chest to indicate where the gift came from. With the heart having cemented its status as a vital organ, receiving it as a present from a loved one came to symbolize the sacrifice and selflessness that define unconditional love. 

Imagery of the heart soon blossomed throughout Europe, appearing on brooches, painted on canvases, and engraved on tombstones. 

How the heart’s symbolism became an obstacle for science

Emotional metaphors of the heart soon became an impediment to scientific research in the late 1800s. Connotations of the heart as a window to the soul led to an ethereal veil of sacredness and fragility being placed upon it. As its symbolism became etched into religious traditions, meddling with the heart came under scrutiny by many in the scientific community. Prominent German surgeon Theodor Billroth was quoted saying, “A surgeon who tries to suture a heart wound deserves to lose the esteem of his colleagues.” 

As the organ’s symbolism persisted, the ethics and even the necessity of cardiovascular surgery fell into question: the heart was deemed sacred, and medically exploring the heart was deemed inappropriate. Consequently, medical innovations in heart surgery slowed in the early 1900s. Few surgeons rose to the challenge of grappling with the wounded heart and the weight of its sociocultural significance. Those who attempted to perform heart surgery were often ridiculed by the rest of the scientific community, with successful operations dismissed as anecdotal or miraculous.

Groundbreaking pediatric operations performed by Dr. Robert Gross and Dr. Alfred Blalcok in the mid-1900s helped establish cardiovascular surgery as a viable and essential option for heart patients. A string of successful procedures paved the way for the world’s first successful heart transplant, performed by South African surgeon Dr. Christiaan Barnard in 1967. This led to an unprecedented media frenzy as the world buzzed with the newfound possibility of “spare part surgery.” 

Heart transplants changed more than just medicine

Yet, ethical dilemmas quickly arose as the social dynamics surrounding the transaction of such a priceless ‘gift’ were considered. The intimacy entangled within transplant surgeries cannot be ignored. With the most symbolic organ of the human body involved, an emotional connection between patient and donor is inevitable. How can one just move on after receiving an entire heart from a stranger? The surgery involves an emotional transaction, as the donor’s death saves the patient’s life.

The heart’s enduring symbolism, combined with its medical allure, made heart transplants a liminal tool for social change, challenging widespread socially constructed differences between people. For example, ideas of inherent biological differences between races were contested through the medical miracle of heart transplants after Dr. Barnard conducted his second heart transplant between a mixed-race man and a white patient. 

The combined effect of a cardiac operation’s innovation along with the heart’s long-standing emotional symbolism emphasizes the organ’s prominence in culture and conversation today. Tracing the development of its symbolism reveals the heart as a crucial subject of human nature, as it floats past the barrier of physical anatomy and into the realm of our cultural consciousness.