Traveling home to California after an international cardiology congress a few years ago, Dr Gregory Thomas stopped in Cairo to visit Dr Adel Allam, an Egyptian cardiologist and nuclear cardiology expert. Dr Allam took Dr Thomas to see the mummies exhibited at the world-famous Egyptian National Museum in downtown Cairo. While there, the two cardiologists took special note of an inscription on one of the glass cases, which announced that the mummy on display, King Menephtah, had suffered from atherosclerosis. Like most of us, Drs Allam and Thomas were surprised that atherosclerosis could have occurred in humans three millennia ago. They immediately questioned the scientific evidence supporting the claim that this 3,200- year-old mummy had suffered from atherosclerosis. Did ancient Egyptians really have atherosclerotic heart disease? After all, heart attacks are the product of ‘modern’ lifestyles. We believe that atherosclerosis and heart attacks are the end result of consuming an atherogenic diet and inadequate physical exercise. Surely the ancient Egyptians ate a more healthy diet than modern humans and lacked the modern conveniences that enable us to pursue sedentary lifestyles? After all, the ancient Egyptians built the great pyramids by hand without modern machinery, and ‘fast food’ was yet to be invented.
These questions did not go away after Drs Allam and Thomas returned to their busy clinical cardiology practices in Egypt and the US, respectively. How do we know for sure that ancient Egyptians had cardiovascular disease? How prevalent was cardiovascular disease in ancient Egypt? What caused cardiovascular disease so long ago? Did ancient Egyptians really have atherosclerosis so long ago? Are our assumptions about the modern lifestyle being responsible for the current epidemic of cardiovascular disease all wrong? To answer these questions, Drs Allam and Thomas asked another question: can modern cardiovascular diagnostic techniques such as computed tomography (CT) be used to investigate the cardiovascular system in mummies that are thousands of years old?
In a classic example of networking, Drs Allam and Thomas put together an international team of friends, friends of friends, colleagues, and grateful patients to answer these questions (see Figure 1). This constantly expanding group includes Egyptologists, preservationists, clinical cardiologists and imaging specialists, philanthropists, and many others— old and new friends all fascinated by ancient Egyptian mummies and interested in the questions raised about heart disease in ancient civilizations (see Figure 2).
Previous Studies
The birth of modern Egyptology is often related to Napoleon’s conquest of Egypt from 1798 to 1801.1 One hundred and sixty-seven scientists and scholars accompanied the military expedition. Among other accomplishments, the French discovered the Rosetta Stone, ultimately allowing the translation of ancient hieroglyphs. Interest in and investigation of all aspects of ancient Egypt are now widespread, with many thousands of scholarly and lay publications. Previous studies of disease processes in mummies have been performed by ‘unwrapping’ the mummies. In the early 1900s, Sir Marc Armand Ruffer2 performed seminal work in Egypt on rehydrated histologic specimens obtained from unwrapped mummies. More recently, Rosalie David3 in the UK created the Manchester Museum Mummy Project, which employs several multidisciplinary methods to examine ancient mummies, including CT imaging and DNA testing as well as anatomic observations made by unwrapping mummies. Dr Zahi Hawass and colleagues4 recently established a modern state-of-the-art DNA laboratory at the Cairo Museum and have reported on important DNA and CT findings in King Tutankhamun’s family. These and many other small studies have reported incidental observations regarding the presence of atherosclerosis and vascular disease in Egyptian mummies, but CT studies have not been systematically performed in large series of mummies.5
Computed Tomography Scanning at the Egyptian Museum
CT scanning, since it is non-invasive and does not harm the mummies, has become an important tool for studying many features of ancient Egyptian mummies. Luckily for our project, the Supreme Council of Antiquities of Egypt and the Egyptian National Museum had previously collaborated with the National Geographic Society and Siemens to obtain a six-slice mobile CT scanner for mummy studies. The scanner is parked adjacent to the Egyptian Museum and has been used for other studies not specifically focused on cardiovascular disease.
In February 2009, our group used this scanner to perform CT scans on 20 mummies housed in the Egyptian National Museum, specifically searching for the presence of cardiovascular tissue and for areas of calcification within the arterial walls, which have been shown to be characteristic of healed atherosclerotic plaques in modern humans (see Figure 3).6 Two additional mummies scanned previously at the Egyptian Museum were included in our first studies of atherosclerosis in mummies.7
These mummies lived between 1981 and 334 BCE. Peripheral arteries including the aorta were visible in 16 mummies; of these, five (31%) had ‘definite’ focal calcifications identified within vessel walls (see Figure 4). ‘Probable’ calcifications were seen in the peripheral vessels of another four mummies. We were able to identify cardiac tissue in four mummies, but coronary arteries were not seen. While we did not directly identify mummies with coronary atherosclerosis, 56% of the mummies examined had evidence of atherosclerosis, which is known to be a diffuse, systemic disease.
The most ancient mummy found to have evidence of vascular calcification in our first study was Lady Rai, nursemaid to Queen Ahmose Nefertari. Lady Rai lived in the time between prophets Abraham and Moses, dying in approximately 1530 BCE at 30–40 years of age, as estimated from CT of her bones. Although corroborative data are incomplete, the mummies we scanned appeared to have been of high social standing—members of the pharaoh’s courts or priests or priestesses. Calcification was present in four of seven women scanned (57%) and five of nine men (56%). Among those who died at an estimated age of 45 years or older, seven of eight (87%) had vascular calcification compared with only two of eight (25%) who died when they were under 45 years of age.
Why Atherosclerosis in Ancient Egypt?
Our CT studies confirm earlier pathologic observations of atherosclerosis in ancient Egyptian mummies,2,3 expanding these observations with non-invasive imaging. We are continuing our studies, scanning more mummies in the hope of identifying coronary arteries, and also extending our observations relative to the aorta, carotid, and peripheral arteries in a larger sample size, including male and female mummies of different eras, different social strata, and perhaps with different ‘risk factors’ for developing atherosclerosis.
Much has been written about the diet, habits, and lifestyles of ancient Egyptians.8 While the ancient Egyptians did not have tobacco, their diet may have allowed or promoted atherogenesis. Ancient Egypt was already an agricultural and developing urban society 4,500 years ago. The ancient Egyptians ate meat, dairy products, eggs, refined grain, and preserved foods such as fish with salt, and drank beer. Exercise may have been avoidable in the royal court. The prevalence of diabetes, hypertension, and obesity is unknown, but there are references in the ancient papyrus texts to symptoms that could have been caused by angina pectoris, myocardial infarction, and congestive heart failure.9
The presence of atherosclerosis in humans many thousands of years ago also reminds us of our evolutionary legacy. Valuable insight may be gained about the origins of atherosclerosis beyond what can be gained by studying its contemporary manifestations.10 The role of inflammation in atherosclerosis is a modern concept, but the inter-relationships between chronic inflammatory diseases in ancient humans, such as tuberculosis, malaria, schistosomiasis, and other infections, all thought to be prevalent in ancient Egypt, and the development of atherosclerotic plaque is the subject of interesting speculation.11
Continuing Studies
We recently returned to the Egyptian National Museum to scan additional mummies, especially looking for those with well preserved hearts, hoping to visualize the coronary arteries as well as the aorta, carotids, and peripheral arteries. We are also collecting CT data from mummies scanned in other museums, including collections outside Egypt. New caches of mummies are being discovered in Egypt. We hope to scan a wider cross-section of the ancient Egyptian population, including individuals of both sexes and all ages, occupations, and social status. We are also studying data complementary to mummy CTs, which may help to explain our findings.
CT is an extremely powerful technique. In looking for atherosclerosis, we scanned the entire bodies and often the coffins of the mummies. While we are primarily interested in cardiovascular disease in the ancient Egyptians, we are collaborating closely with many other disciplines, including specialists in bone and dental disease, radiologists, genetic and forensic scientists, Egyptologists, preservationists, and others who may find our CT data useful.
Study of ancient Egypt, and particularly the examination of mummies, excites many people from all walks of life. We have been fortunate to be able to apply modern diagnostic methods to the study of ancient human beings, and hope to continue our work together. We are challenged and inspired as clinical cardiologists, scientists, and academicians working together as friends on this unique project.
Acknowledgments
We are grateful most of all for the generosity, kindness, and grace of the Egyptian people, who shared their ancient civilization and priceless artifacts with us. We especially thank Dr Zahi Hawass, Director of the Supreme Council of Antiquities of Egypt. All those who helped us are too numerous to name, but we are particularly grateful to Mr Barry Hon of Dana Point, California, Siemens AG of Florsheim, Germany, and Tarek Amer, CEO of the National Bank of Egypt, for their generous support of this project. Further information on the project can be found at www.paleocardiology.org