Heart. Johannes Hinrich von Borstel

has laughed a lot and spent the time in a fulfilled way.

      The good news is that anyone can take preventive measures to make sure the time when their heart stops beating comes as late as possible. And, at best, without cardiovascular disease ruining our existence before it does.

      The first step towards this goal is keeping a sense of humour. Life can sometimes be an extremely serious business, but everything is easier when you’re smiling. You could try laughter yoga. Or just search ‘quadruplet babies laughing’ on YouTube.

      It’s not only hypochondriacs who interpret trivial symptoms as the harbingers of death-bringing illness. No one is completely free of this crippling habit — not you, not me, not any of us. But the great thing is that, as a rule, human beings are basically healthy creatures. And that’s true of the heart, too. When some part of our body feels strange, it’s usually not due to a rare disease that will carry us off in a matter of hours, but due to something completely harmless. True to my favourite saying: ‘If you hear hoof beats, think horses, not zebras.’ So there is nothing standing in the way of personal happiness and physical health. But, still, I sometimes like to listen carefully to my heart.

Medics and Money before Midnight

      I lie in bed and listen to my own heart hard at work. It’s beating a little harder than normal because I swam a few lengths before going to bed. Looking at my alarm clock, I count 19 beats in 15 seconds. I do the math: four times 19, or 19 times two times two. Or two times 38, equalling 76 beats a minute. I look down at my chest and watch it pulsating with each beat of my heart.

      As a doctor-to-be, I have my stethoscope at hand. I listen to my chest. Ba-boom, ba-boom, ba-boom, ba-boom, ba-boom. I’ve just celebrated by 25th birthday. That means my heart has already beaten around 900 million times during my lifetime. Faithfully and dependably fulfilling its duty of keeping me alive. Thank you, dear heart, for doing that monotonous job for me.

      But listening a little more carefully, it becomes clear that the work of the heart is not quite so monotonous after all. It does not simply go boom, boom, boom, boom like the bass from the speakers of your stereo system or boombox. In fact, a heartbeat consists of more than just the simple contraction of the entire organ. It is a precisely timed and coordinated operation of the muscles of the atria and the ventricles, as well as the opening and closing of the heart’s valves.

      First, the atria contract and press blood into the ventricles. This process can’t normally be heard through a stethoscope. A short time after, normally about 150 milliseconds, the ventricles contract, transporting the blood into the lungs and eventually the rest of the body. That contraction of the ventricle muscles is what causes the ‘ba-’. The subsequent ‘boom’ isn’t caused by the heart muscle itself, however, but by the closing of the semilunar valves of the aorta and the pulmonary artery. I place the stethoscope on another part of my chest. The sound changes. A little further up, and it changes again. I could happily spend hours just moving my stethoscope around.

      What particularly fascinates me on this evening are the sounds made by the valves of my heart. They make sure that the blood travelling through our heart always moves in one direction and doesn’t suddenly go into reverse gear. As we have seen, anatomists identify four valves, two of which are atrioventricular (the mitral and tricuspid valves) and two of which are semilunar.^* Always alternating, they open and close, creating specific sounds that can be attributed to each valve. Medics distinguish between four heart sounds, although only two can be heard through a stethoscope.

      The first of these heart sounds is caused by the contraction of the ventricular muscles. It is sometimes called S₁ by medics. The second, higher-pitched sound is shorter in duration than the first and is somewhat sharper and louder. Known as S₂, this sound is caused by the closing of the two semilunar valves. During inhalation, it can change and split into two components if the aortic valve closes a little earlier than the pulmonary valve.

      As any parent or teacher will confirm, children and teenagers make more noise than adults — and the same is true of their hearts. The third and fourth heart sounds can’t be heard through a stethoscope in a healthy adult, but they can sometimes be picked up in younger people. The third sound (S₃) is heard when the left ventricle of the heart is filled with blood. It is normal in pre-adulthood. When it occurs in older patients, it can be a sign of problems. More precisely, it can indicate a problem with the mitral valve between the left ventricle and the left atrium,^* an abnormal increase in the size of the ventricular cavity,^† or cardiac insufficiency ( failure of the heart to work hard enough). And if the amount of blood remaining in the ventricle when it refills is too great, the new lot of blood will slosh against the old and this will also cause a sound.

      The fourth sound (S₄) results from the contraction of the atria. If it’s heard in adults, it can be an indication of high blood pressure, a thickening of the muscle of the ventricular wall, an obstruction in the left ventricular outflow tract, or — more rarely — a narrowing, or stenosis, of the aortic valve. It is generally followed immediately by the first heart sound.

      Hearing all this with a stethoscope is a true art. Some doctors have such a finely tuned ear that they can hear not only the tiniest changes in the sounds of the heart, but also microtumours in the lungs. This involves placing the stethoscope on the chest and tapping in specific places. Theoretically, it’s possible to identify such tumours by listening to the resulting echoes, but I have never managed such an impressive act. I suppose this is a case of constant ‘practice makes perfect’.

      Despite this, my stethoscope is always a great aid, for listening not only to the heart, but also to the rest of the body. I grew up in Germany’s Harz Mountains, an area of the country that is very popular with motorcyclists in the summer. Serious accidents are common in the biking season and those horrific crashes often leave bikers with terrible injuries. On arriving at the scene of such an accident as part of an emergency medical team, I would begin by listening to the patient’s lungs and abdomen. I did this because it’s not uncommon to hear no sound of breathing on one side of the chest, even if the patient is still breathing.

      The cause of this apparent contradiction is usually a collapsed lung (pneumothorax) on the side where no breathing sound can be heard, but it can also sometimes indicate an accumulation of blood in the chest cavity (haemothorax) or, in a worst-case scenario, a combination of both (haemopneumothorax). The sound made by tapping on the chest while listening through a stethoscope (doctors call this ‘percussion’) can allow a medic to distinguish between accumulated air and accumulated blood. An accumulation of air gives a sound reminiscent of beating on a drum, while an accumulation of fluid will dampen the sound, like striking a kettledrum filled with water. If the patient were able to sing and play the guitar along with all this percussion, they would almost be ready to take to the stage for a performance — if it weren’t for the fact that they were in need of urgent medical treatment.

      During a routine medical examination, the doctor will often listen to the abdomen using a stethoscope, to check the function of the intestines. After a motorbike accident, the medic will ‘percuss’ the abdomen to identify whether there is any internal bleeding or accumulation of fluids. As you can see, the stethoscope is a constant and valuable companion of medical practitioners; it is indispensable in many areas of treatment, but especially that of the heart.

      However, like everything else, it has its limits. There are specialist cardiology stethoscopes with which you can almost hear the worms moving beneath the soil, but even they do not allow doctors to perceive everything — for example, the third and fourth heart sounds. For that, a special ultrasound examination of the heart is necessary (called an echocardiogram). It allows doctors to check the size of the heart, its atria and ventricles, the thickness of its walls, its overall mobility, its valves, and any defective blood flows. Often, a doctor will also be able to monitor for pathological changes to a patient’s heart, including defects in the valves or constrictions in the coronary blood vessels.

      While I was a medical student, I learned a mnemonic that has stayed with me ever since: ‘All Physicians Take Money at 22.45’. I’m sure all physicians