It’s spring party time. Backyard barbecues, drinks on the porch, work or school gatherings. Inevitably, the conversation lags, and you need something to stimulate a new topic of discourse. Nothing picks up a mundane interaction more quickly than an interesting fact about the human heart. Today, then, I bring you Fun Cardiovascular Physiology Facts, courtesy of Loe and Edwards, Cardiovascular Pathology 2004.
- Each day, the heart pumps 100,000 times. In 1 year, the heart beats approximately 37 million times. In a 70-year lifetime, the heart will beat more than 2.5 billion times.
- In adults, the heart weighs less than 0.50% (or about 1/200th) of one’s total body weight.
- Heart size is directly proportional to body size, but heart rate is inversely proportional to body size. This is true for humans and animals. The heart of a blue whale is the size of a compact car and beats 5–6 times/min in shallow water but only 3–4 times/min during deep dives. The heart rate of an elephant is 30 beats/min (bpm), and that of a shrew is 1000 bpm. Among birds, the blue-throated hummingbird has a heart rate of 1260 bpm during flight but only 36 bpm during torpor (nighttime cooling), when its body temperature drops by as much as 20°C (35°F).
- The normal resting heart rate is lowest in the morning and highest in the early afternoon, and the lowest recorded resting heart rate is 28 bpm (Miguel Induráin, Spanish cyclist).
- At rest, the heart pumps more than 1 L (more than 1 quart) every 10 s, or about 5 L (about 5 quarts) of blood per minute. During the third trimester of pregnancy, the heart pumps 7–9 L/min, and at peak exertion, the heart can pump 20–35 L/min.
- In 1 day, the heart exerts enough power to lift a 1-ton weight 12.5 m (41 ft). In a 70-year lifetime, the heart will pump about 200 million L (more than 1 million barrels) of blood, or enough to fill three super tankers.
- The blood vessels (arteries, capillaries, and veins), laid end-to-end, would measure about 100,000 km (60,000 miles), or approximately 2.5 times the circumference of the earth.
- Tissue the size of a pinhead contains 2000 to 3000 capillaries.
- Every day, red blood cells travel approximately 19,000 km (12,000 miles) or about four times the distance from New York to Los Angeles.
- Stacked atop one another, the body’s red blood cells would span 50,000 km (30,000 miles).
- Cardiovascular disease has been the number one killer every year since 1900, except 1918 (the year of the influenza epidemic).
- The longest reported cardiac arrest before beginning successful resuscitation is 4 h (in a Norwegian hypothermia victim).
- In virtually every language, the word “heart” has been used to denote not only the anatomical organ but also our emotions.
Still not feeling party ready? I guarantee, this video will complete your party prepartion. You can thank me later.