Autonomic control of heart rate during prolonged altitude exposure studied by spectral analysis.

Investigators: Christian Otto, B.Sc. & Andrew Pipe, M.D.

The ’96 Mount Logan Expedition for Heart is a scientific expedition involving several areas of study including high altitude cardiac research. In association with the University of Ottawa Heart Institute, The Human Performance Research Fund, and The Canadian Academy of Sport Medicine, the expedition team will be studying the effects of high altitude on the heart in a very unique and noninvasive manner.

The purpose of this research is to gain a better understanding of how the central nervous system controls heart rate, which is an important factor in understanding cardiac disease. High altitude exposure offers a unique opportunity to study this relationship because the decreased partial pressure of oxygen at high altitudes, places increased stress on the cardiovascular system as it supplies oxygen to the body's tissues. Over the course of the ascent of Mount Logan, data on the climber's heart rates will be recorded over a fifteen minute period, early every third morning.

The collection of this data involves the application of electrocardiogram (ECG) electrodes to a specific location on the climber's chests. The ECG electrodes are then connected by electrode lead wires to the Holter monitor which is a simple device resembling a small portable cassette player. The Holter monitor then records the electrical activity of each heart as an electrocardiogram, which will be analyzed for changes in the climber's heart rate.

There are important clinical applications to this research, for it will help to increase our understanding of how the central nervous system controls heart rate. In turn, this will affect our comprehension of similar mechanisms which play a role in the pathophysiology of essential hypertension, ischemic heart disease and congestive heart failure.

Remote Mobile Telemedicine:

The satellite transmission of medical data from Mount Logan

Telemedicine is the transmission of medical data - in the form of voice, video or written text - over a distance. Throughout the ascent, the Mount Logan Expedition Team will demonstrate the reach and potential of exciting new technology through the transmission of cardiac data, voice and video images, from the remote, polar-like environment of Mount Logan, to the Ottawa heart Institute, 4,000 kilometres away.

To achieve this transmission, data on the heart rates of the team members will be collected and downloaded (along with digital camera images) to the expedition's laptop computer. The stored computer files are then transmitted via the MSAT Communicator, a mobile satellite phone provided by TMI Communications. The mobile satellite phone sends the data via TMI Communication's geostationary MSAT-1 satellite, orbiting 36,000 kilometres above the earth, back to TMI's Network Operations Centre in Ottawa., where it travels through the regular telephone network to the Heart Institute. There, cardiac physicians can monitor, interpret and analyze the data.

These innovations in telemedicine make medical diagnosis and emergency care possible in remote locations currently lacking a traditional telecommunications infrastructure. Such technology has numerous potential applications internationally, in such areas as disaster response efforts, remote civilian and military operations, and in space operations.