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Cardiac Congestion

Heart attacks and how they happen

The First Time

It’s a grey Saturday in autumn. The wind whips across the fields, and the rain pelts the tarmac in sheets. The streets are deserted except for the occasional car passing by. It has been more than a year since my work experience in the emergency department at the hospital. I’m 16 years old. Having completed the theoretical part of my training as a paramedic during weekends, I’m now ready for a three-week work-experience placement where I’ll begin my practical training in an actual ambulance team.^* I’m walking to the ambulance station to begin my first shift. The terrible weather does nothing to dampen my great expectations, nor does the fact that, in my excitement, I have not only forgotten to pick up my umbrella and put on my waterproof shoes, I’ve also left my packed breakfast at home. Luckily, it isn’t a long walk.

Full of anticipation, I’m excited about my first ambulance call-out. What will it feel like? To be constantly on the go, flashing lights and blaring sirens, with total focus on the emergency at hand — illnesses, accidents, battles against the sheer forces of nature? I am ready to face any challenge! What I do not yet realise is that this is the day that will not only try my self-confidence to the limit, but also severely test my resolve to enter the medical profession at all.

After a few brief introductions in the station, I’m handed my uniform. It fits like a glove, and my chest swells with pride as I put it on. I am also given a handy little pager that will inform me of an emergency by beeping at me. Then I receive a tour of all the different machines and equipment in the ambulances.

As I’m chatting with my new colleague in the vehicle depot, the shift supervisor enters, with a slightly grumpy look on his face. ‘Hello, Mr von Borstel, nice to see you here. I see you’ve been introduced to all the equipment and made some friends,’ he remarks coolly.

‘Yeah, yes, I have,’ I stammer in reply. ‘I’m very grateful for the opportunity to be here!’

He looks me calmly up and down, and a smile slowly spreads across his face. He tells me he has an important and highly responsible job for me. Ten minutes later, I find myself battling manfully against the sheer forces of nature for the first time. With a broom. In the driveway.

Is it a test? Some kind of initiation rite? Whatever: I don’t care. Proudly sporting my safety vest. I do my leaf-sweeping duty in the rain. After an hour or so, I finish my fight against wind and weather, and withdraw to the staff room inside the station. In the staff room, there are couches, a TV, a small kitchen, and a bookshelf, from which I promptly choose some reading matter. Time passes, but there is not the slightest peep from my pager. My colleagues sit calmly with their pagers clipped to their belts, but I can’t resist checking the battery level on mine every few minutes. Where are the emergencies? At lunchtime, we warm up some soup. I wash the dishes. And nothing else happens.

It is unusual for absolutely nothing to happen during a 12-hour shift. Yet with two hours to go, it seems like we’re heading for a shift without a single call-out.

Somewhat frustrated, I move downstairs to the vehicle depot and open the side door of an ambulance. I check the contents of every single drawer once more and try to commit to memory the way the emergency backpacks are organised.

And then, just as everyone has given up hope, it happens. I feel something vibrating on my belt and hear an insistent beeping. A call-out! My colleagues come rushing down the stairs, and a few seconds later we are tearing through the streets with blue lights flashing and sirens wailing. All we know is a name, an address, and the fact that the patient is having difficulty breathing.

Stefan, Sina, and I pull up outside a house. I grab my emergency backpack and the mobile oxygen cylinder, while Stefan takes the ECG machine.^* We head straight for the front door of the house. I am buzzing with motivation; nothing can stop me now. Well, almost nothing. My mission comes to an abrupt and premature end when, in my boundless enthusiasm, I run headlong into the locked front door. Steady now! Ring the bell first. A light goes on.

‘I’ll be right with you,’ we hear the voice of an elderly woman from inside. Through the glass door, we see the silhouette of a human figure. She’s hunched over and walks very slowly. ‘I won’t be a minute,’ she says through the frosted glass. We wait. I’m charged like a live wire, but I can’t help but be impressed by the sense of calm emanating from the woman behind the glass.

Finally, we hear the sound of the door being unbolted, and a lady with a snow-white perm opens it. She smiles. ‘Do come in,’ she says politely and ushers us inside.

‘Did you call an ambulance?’ asks Sina.

‘Yes. My husband’s in the living room. He’s having trouble breathing again,’ she sighs.

Weighed down by all my equipment, I trot after my colleagues down a dark hallway and into a barely brighter living room. The window blinds are half-lowered, and the flickering television screen is the only direct source of light. The furnishings in the room are old-fashioned — probably older than I am — but well cared for: a dark wood shelf unit, holding a few books and china plates; the television next to it; a coffee table with a brown-tiled top; and a couch, where a man aged around 75 sits, his face bright red. He is clearly struggling to breathe.

While I switch on the light, Stefan introduces us and immediately turns his attention to the patient. ‘You called us because you can’t breathe properly? When did this start?’

‘I …’ he gasps with difficulty in response, ‘I was just getting up from the couch, when …’ He pauses for breath. ‘It was as if I was being strangled.’

In the background, I prepare the oxygen supply. I have two ways to give the patient this life-saving gas: via a mask placed over his mouth and nose, or via a nasal cannula. The latter is a plastic tube attached at one end to the oxygen cylinder, splitting into two branches at the other end. Oxygen flows out of the branches, which are placed in the patient’s nostrils. The amount of oxygen flow can be controlled by a valve on the cylinder.

I try hard to remember what I learned in training. Six litres per minute is the maximum amount to administer through a nasal cannula. Otherwise, the membranes inside the patient’s nose are in danger of drying out. And in his condition, our patient has enough to contend with without that as well. After all, the oxygen is supposed to aid breathing, not make it harder. I could also opt for the mask. But then he will need at least six litres, or there’s a danger the patient will not get enough of the oxygen. I waver. I might not give him enough oxygen through the cannula, but patients often find wearing a mask uncomfortable. After much consideration, I decide the patient will just have to deal with the discomfort of the mask.

Stefan ascertains the man’s medical history and symptoms. ‘Are you in pain, and if so, where does it hurt?’

‘Here,’ the man wheezes and points to his chest, on the left.

‘Do you have any allergies?’

‘No!’

‘Do you take any medication regularly or have you taken any today?’

‘No!’

‘Do you have any other medical conditions?’

‘Yes, diabetes.’

‘Type 2?’

‘Yes,’ he coughs, ‘type 2.’

‘Do you take insulin?’ asks my colleague.

‘Oh, yes … but just a little injection before each meal.’

Aha! This is something I was warned about in training, and now it’s happening during my very first call-out. It is in fact extremely common for patients who take regular medication to deny it with full conviction when asked. I can’t offer any explanation for this. It seems as if, for many people, taking medication regularly becomes routine, like brushing their teeth every morning. So they consider their pills, or even the contents of a syringe, no differently from the spoonful of sugar they take in their coffee or tea. It is certainly not deliberate deception on the patients’ part — but in an emergency situation it can be deadly dangerous.

Stefan continues to question the patient about his medical history. ‘Have you ever had difficulty breathing before, or have you been ill with anything other than a cold and your diabetes?’

‘No, just diabetes!’ answers the patient resolutely.

Yet suddenly, as if from nowhere, his wife joins the conversation. She has slowly but surely shuffled down the hallway into earshot. ‘Tell them about your angina!’ she shouts. ‘Angiiiiinaaaa!’

With a slightly annoyed roll of his eyes, the elderly man tells us he was diagnosed with angina pectoris^* two years before, but no longer takes medication for it. He reports intermittent difficulty breathing, but says it always went away again and has never been this bad.

While Sina places the blood-pressure cuff on his arm, I offer him the oxygen mask, which he literally snatches from my hand and presses over his mouth and nose. I decide to begin with eight litres per minute. Using a pulse oximeter attached to his finger, I measure the oxygen saturation of the patient’s blood. It seems pretty normal at the moment. But the man’s blood pressure and heart rate are both high. This may be due to stress, or it could have a much more serious cause. Chest pain, breathing difficulties, and heart problems in the past — all the alarm bells are ringing.

My colleague takes an ECG reading while I prepare an infusion. As soon as the first lines appear on the ECG, our suspicions are confirmed: it’s a heart attack!

Less than two minutes have passed since we arrived, and the patient’s condition is rapidly deteriorating. He’s having increasing difficulty breathing, and although I have turned the flow up to maximum, the oxygen saturation of his blood is plummeting. My colleagues do everything in their power to help him, while I feel rather at a loss. I follow my colleagues’ instructions, preparing a needle and antiseptic for an intravenous catheter. As Stefan prepares to insert the needle, the man, now pale and blue-lipped, looks at me with fear in his eyes. His blood pressure is falling, his ECG is becoming ever more erratic, and the atmosphere is growing ever more sombre.

Sina speaks to him, trying to reassure him; the man never takes his eyes off me. His look screams, ‘Help me!’

This is the worst feeling of my life so far. Inside my head, there’s complete turmoil. What else can we do for him? Did my grandfather suffer like this? The man’s gaze seems to pierce right through me. For a brief moment, I have the feeling that it’s my own grandfather looking at me. Then, all of a sudden, the old man keels over to one side and loses consciousness. Before he can slide off the couch, Stefan catches him and lowers him carefully onto the carpet.

A quick check: breathing — yes; conscious — no. Place the patient in the recovery position and prepare to unblock the airways by suction if necessary; I remember my textbooks, and act accordingly. Get suction pump out of the rucksack, attach suction tube. A quick test and we’re all set. If the man should start to vomit, I can quickly jump in with my pump.

The man’s wife sits silently on a chair by the living-room door. We hear the howl of a siren coming from outside: the emergency doctor has been called and is on his way. Thank God for that! Sina asks the lady to go open the door. Just as she leaves the room, it happens: there’s a piercing beeping noise, and the lines on the ECG begin to jump crazily. Ventricular fibrillation! A condition in which there is rapid and uncoordinated contraction and relaxation of the muscles of the ventricles of the heart, making it unable to pump blood.

Stefan immediately begins CPR (cardiopulmonary resuscitation) procedures, Sina prepares the defibrillator and I unpack the intubation equipment. At that moment, the emergency doctor enters the room. My colleague quickly fills him in on the situation, and then off we go: the man is defibrillated, which means we try to force his heart back into a normal rhythm with strong electric shocks. At the same time, we insert a tube into his trachea (windpipe) and ventilate him artificially, as well as giving him all sorts of drugs. For more than three hours, we try to keep him alive, but without success. This is my first emergency call-out, and it has ended in disaster.

When we return to the station later that evening, the nightshift team is already there, ready to take over. My colleagues hand the ambulance over to them as I dejectedly make my way home. I can’t help wondering if I made some mistake, if there was anything more I could have done. Is this really the right job for me? Can I bear to watch people dying on a regular basis?

On arriving home, I study all the chapters on heart attacks in my collection of books for the umpteenth time, trying to find out where I might have gone wrong. This feeling of insecurity is new for me. It is some time before I realise: we didn’t make any mistakes. For better or worse, I have to come to terms with the fact that even a trained paramedic can’t save everyone.

Of Dragon Boats and (Oar) Strokes

A healthy human heart is about the size of a fist. Depending on body size and fitness level, it can weigh between 230 and 280 grams (8–10 oz) in an adult. It’s made up mostly of heart-muscle cells, known to doctors as cardiomyocytes. There are two types of heart-muscle cell, and — a little bit like the staff on a hospital ward — there is a strict hierarchy between them.

The first type is the cells of the working heart muscles, which are responsible for making the heart beat by tensing and relaxing. They may be in the majority, but they can’t escape the tyranny of the other, minority cell type: those of the heart’s electrical-conduction system. Just like a pacemaker, these cells generate an electrical impulse and conduct it to the cardiomyocytes to cause the heart to beat. The two types of cell are like the drummer dictating the stroke and the rowers in a traditional Chinese dragon boat.

These two cell types differ not only in their function, but also in their appearance. The pacemakers are somewhat larger than their colleagues, and have a ‘pale and interesting’ look about them. With impressive regularity, they make sure the heart beats at a constant rate — between 60 and 80 times a minute at rest. Provided, that is, that they are healthy and functioning as they should.

Unlike some of the other organs of our bodies, the heart has very limited regenerative capabilities. Compared to the liver, which can renew its cells exceptionally quickly, and even the lungs, which manage the same trick but at a much more leisurely pace, the heart is at the bottom of the regeneration league. Fewer than half the heart’s cells are replaced over the course of an entire human life.

Despite this, the heart has all the cardiomyocytes it needs. The left ventricle alone is made up of an estimated six billion cells. If you were to look at each one of these cells through a microscope for half a second, you would have to spend almost 200 years at the eyepiece. That’s without counting breaks for sleeping, eating, or satisfying other natural needs. Wow! That’s a lot of cells! This naturally raises the question of where the heart gets all the energy it needs to pump some five to six litres (1–1.5 gallons) of blood per minute, even when the body is at rest. The answer is simple: the heart is a believer in self-sufficiency.

Soon after the blood has exited the left ventricle to enter the body’s circulatory system, it can take one of three possible routes. Most of it flows through the aorta towards our internal organs, arms, and legs. If it does so, it bypasses two exits just beyond the aortic valve, which lead to the right and left coronary arteries. Those vessels spread out into many smaller branches and supply the tissues of the heart with the nutrients they need.

At first glance, the pattern of those branches appears to be very similar from person to person, but a closer examination reveals that the details vary widely. Just like actual trees: a trunk in the middle, some branches, and a lot of leaves. It’s not until you look more closely that you see each tree’s particular characteristics, such as, for example, the pattern of the branches, the shape of the leaves, and the colour of the blossom.

In a left-dominant heart, the left coronary artery also supplies the posterior wall of the heart with oxygen and nutrients; in a right-dominant heart, this task is done by the right coronary artery. The most common type is the one in which both coronary arteries provide that supply in equal measure. This type is described by cardiologists as co-dominant.

Apart from forming branches, the coronary arteries can also form anastomoses. These are new connections created between blood vessels to make sure that effectively all the muscle tissue of the heart is constantly provided with the best possible supply of blood. Unfortunately, when one of the larger blood vessels becomes blocked in a heart attack, these anastomoses are almost never able to create a circulatory bypass as an alternative route to guarantee the continued supply of oxygen to the heart muscles.

When a heart attack occurs, the undersupplied tissues of the heart begin to die. This can have varying consequences, depending on the location and size of the area supplied by the blocked artery. In the worst case, the heart simply stops beating immediately. If some of the rowers stop rowing, the boat may either start to spin round in circles or come to a complete halt. If the pacemaker stops beating its drum to dictate the rhythm, all the rowers will begin rowing for all they are worth, but out of synch with each other, so the boat still fails to move an inch. Sometimes, however, the reduced blood supply causes only slight irregularities in the rhythm of the heartbeat, and such very minor heart attacks often go unnoticed.

An arterial blockage — doctors call it an occlusion — leading to a reduced blood supply to the right side of the heart often causes the jugular veins of the neck to become engorged, since the blood flowing through those veins back to the heart can no longer be pumped into the pulmonary circulation system quickly enough by the right side of the heart. This leads to a traffic jam in the jugular. And no one likes a traffic jam.

An insufficient blood supply to the muscles of the left side of the heart, on the other hand, often leads to an accumulation of fluid in the lungs, known to doctors as pulmonary oedema. This is also caused by a traffic jam, but this time the blocked blood backs up in the pulmonary vein all the way to the tissue of the lungs. This builds up the pressure, causing fluid from the capillaries of the alveoli — the little air sacs in the lungs — to be pressed into the cavities that are normally filled with air, flooding them. This can be so conspicuous that a bubbling in the chest may be heard even without the aid of a stethoscope. In especially serious cases, the lungs can become so full of foam that the patient has to cough terribly hard to get rid of it. This can be a rather disgusting process, not only for the person concerned, but also for the emergency medical team treating the patient.

If no emergency doctor is on the scene at this point, the hands of a paramedic are basically tied. She can do little more than a trained first-aider. Of course, a paramedic can administer oxygen, but a first-aider can also simply open the window to help the patient breathe more easily. If the symptoms of such cardiac congestion become so serious that the patient’s heart stops beating, anyone (not just a qualified medic) who discovers the unfortunate person should immediately begin resuscitation procedures. It would be good to have your last first-aid course fresh in your mind, but even less-than-correct resuscitation attempts are better than none at all.^*

In addition to this, one thing is particularly important that has nothing to do with medical knowledge, machines, or electric shocks. It is providing for the patient’s general comfort. This is so important because patients who are suffering a heart attack are often extremely frightened. The more anxious a person is, however, the more stressed he will be, and the faster his already-weakened heart will beat as a result. And that could be the final nail in his coffin, so to speak. For this reason, it is crucial to create as pleasant an atmosphere as possible during the time until professional help arrives, and, again as far as possible, to radiate a sense of calm. When the patient feels he’s in the care of someone who means him well, he will automatically feel better. If the patient is confronted with someone who is nervous and agitated, on the other hand, he will become increasingly anxious himself. Simply responding sympathetically to the patient’s immediate needs is a great help. If the patient is cold, cover him with a blanket; if he has difficulty breathing, open a window. It has been proven that such simple actions can increase the patient’s chances of survival, even in seemingly hopeless cases.

The same is true, of course, for stroke patients. That term is going to crop up several times, so let me explain it briefly here. A stroke^* occurs in almost exactly the same way as a heart attack — only in a different organ. Our brain is permeated by a network of vessels that supply it with blood. This blood supply is important because our grey matter is made up of nerve cells that can only work if they receive sufficient oxygen via the blood. If one of the blood vessels in the brain ruptures, bursts, or becomes blocked, the area of the brain it supplies will no longer receive an adequate supply of blood and will die — unless the blockage is removed at once. By analogy with heart attacks, strokes are therefore also sometimes referred to as brain attacks.

Strokes can have very different consequences, depending on which blood vessel and which part of the brain are affected. Small blockages often go completely unnoticed, but if the area of the brain responsible for speech is undersupplied with blood, patients’ speech may become slurred and indistinct, they may begin to say strange things, or they may lose the ability to say anything at all. When someone suffers such a cerebral infarction, time is of the essence. Within just a few hours, damage can become irreparable and permanent since, like the heart, the brain has very limited regenerative powers.

Of course, the best thing is to avoid any infarction — either cardiac or cerebral — in the first place. Treatment and care may be very good these days, but they are still unpleasant and dangerous. And it is, indeed, possible to reduce your risk of suffering a heart attack. Although, there are two factors we cannot influence: genetic predisposition and gender. Men are considerably more likely to suffer a heart attack than women. It’s not until they have gone through menopause that women’s risk increases, for which they have the change in their hormone balance to thank. But there are a whole range of factors that we can influence and that can increase our risk of suffering a heart attack immensely. If we avoid these risks, the danger is reduced. It can be that simple!

*An unusual situation for someone my age, but I had great enthusiasm!

*A device for recording the electrical activity of the heart in the form of an electrocardiogram (ECG). See also, ‘If You Can See the Steeple, the Graveyard Isn’t Far’, p. 157.

*Latin for ‘strangulation in the chest’; a temporary obstruction in the blood circulation of the heart, which is often associated with narrowing of the coronary arteries.

*See also, ‘Quit Playing Games with My Heart’, p. 168.

*Also known by many other names, including cerebral infarction, cerebrovascular accident, or cerebrovascular insult; formerly also apoplexy, palsy, or, in Latin, apoplexia cerebri.