A letter from the heart to its owner: Talking about sick sinus syndrome

Author: Shen Songcui Shanghai Chest Hospital

Reviewer: Huang Jingjuan, deputy chief physician, Shanghai Chest Hospital

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Dear Master:

As I write this letter, I have served you for 64 years, 5 months and 28 days. It is a great honor to have been with you for so many years.

I think none of us want to talk about the nightmare-like experience one month ago. At that time, you were lying quietly on the plastic track in the park, unconscious. People around you gathered around with concern, and a young man patted your shoulder and called you loudly. But everything around you seemed far away from you, and I felt the same way. I was experiencing the most serious "downtime" since my "birth". I tried desperately to "restart", but the deep feeling of powerlessness made me feel unprecedented despair! After a full 6 seconds, I barely contracted, but what followed was another suffocating stop! At that time, I seemed to see the gates of hell slowly opening to us...

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Thanks to the timely arrival of the ambulance, we were taken to the emergency room of the nearest hospital. The doctor comforted your family and quickly explained the condition and emergency treatment measures to them. It was the timely surgery that brought us back from the brink of death and we were able to wake up again!

Now, the question is - looking back over the past few years, have you really been as you said, holding me in your arms when I'm happy, holding me in your arms when I'm sad, and taking good care of me? Have you listened attentively to my "voice" and cared about my changes?

In fact, under your neglect, I have changed a lot, and it all started with my "good friend" - the vagus nerve. From childhood to adulthood, it has always been able to soothe my emotions very well. It can release a substance called acetylcholine, which slows down my heartbeat frequency and stabilizes my state, especially at night. However, in the past three years, I gradually feel that this just right "relaxation" has evolved into laziness and slackness. During the period when you fall asleep, my heartbeat frequency not only gradually decreases, but also pauses from time to time. Slowly, this situation continues from late at night to daytime!

As the "idol" worshipped by all the other tissues and organs in your body, your brain, stomach, intestines, kidneys, etc. are all my senior "fans", and they all rely on me to pump blood. Therefore, if I make a mistake, it will cause a big wave in the "fan circle". And my recent frequent conditions have made my "number one fan" - the brain release a sense of dizziness to you, trying to force you to stop what you are doing and listen to our "grievances". It's a pity that although you feel dizzy and dizzy again and again, you think it is caused by low blood sugar, eat a piece of chocolate, take a rest for a while, and then continue to work.

The annual physical examination for retired employees is your chance to discover problems and correct them in time. However, even if you see an electrocardiogram report with a heart rate of only 48 beats per minute, even if the doctor repeatedly emphasizes the seriousness of the condition and recommends that you go to a large hospital for a dynamic electrocardiogram, you always respond nonchalantly: "I was an athlete when I was young! I still run and play on the horizontal bar every morning! Besides, won't my heart beat slower when I get older? There's nothing wrong with my heart, don't make a fuss!" Your stubbornness makes the doctor at the physical examination institution helpless, and you secretly feel lucky that he didn't "succeed in fooling you." But, my master, I can't bear your "trust"!

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As time went by, I became more and more lazy and felt more and more exhausted. The length of my downtime also gradually developed from 2 seconds to 3 seconds and 4 seconds... I also joined my "fans" to express my dissatisfaction to you in various ways, so that you would face my problems. My "fan girl" - the autonomic nerves would pull from time to time, and although you immediately felt chest tightness, you just massaged the uncomfortable area and dripped a few drops of cooling oil on your chest. My "fan brother" - his legs were also very anxious, deliberately dragging your steps and making you feel heavy in your lower limbs. My "number one fan" - the brain pushed "serial warnings" to you, making your dizziness worse and your memory worse. Once, you almost caused a disaster because you forgot to turn off the gas stove! However, you are still indifferent to your situation! So, the brain simply used the ultimate "killer move" - ​​blackout, which made your eyes blurry for a while, sometimes even pitch black, and it took more than ten seconds to recover. However, you still do your own thing! So, there happened the scene that happened on the track one month ago: your bad friend thought you were running too slowly and proposed to race with you. You, unwilling to admit defeat, immediately accepted the challenge. Although you were far behind and exhausted, you still forced yourself to speed up and try to catch up. That was the last straw that broke the camel's back for me.

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After surviving a disaster, I believe that now, in addition to feeling fortunate, you are also paying more attention to the disease I suffer from.

Now, pay attention to the blackboard and mark the key points!

This disease is called sick sinus syndrome. For example, every time I contract, it is achieved by a hidden "wire" inside that transmits the pacing information to the myocardium. This "wire" is called the "cardiac conduction system", and the "source" of the pacing information is located in the upper right corner of the right atrium, called the sinoatrial node. As we age, the sinoatrial node gradually undergoes changes such as degeneration. When it cannot issue the command to beat on time, I will stop beating. In the past nearly 3 years, symptoms such as dizziness, chest tightness, fatigue, blackouts and memory loss are all distress signals sent to you by me and my "fans"!

Next, let's talk about the "new friend" that the doctor implanted in my body. It's called a pacemaker. Although it's small in size, it plays a big role. Its flat and round body is covered with a metal coat, and it extends two long wires into my body cavity, entering my right atrium and right ventricle respectively, and can feel my beating signals. When it detects that I am weak and stopped working, it will send out pulses to stimulate me to contract and beat, to ensure that my beating frequency does not fall below a certain lower limit, so that the blood supply work that I am responsible for will no longer have the previous pause.

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Finally, please allow me to give you some suggestions. First, exercise within your ability. If you feel uncomfortable, please stop immediately. Second, please take your annual physical examination seriously. For any abnormalities in the examination report, you must listen to the doctor's advice. Also, although you have a pacemaker implanted in your body, it is not a permanent solution. The average life of a pacemaker battery is 6 to 8 years. It is recommended that you go to the pacemaker clinic of the hospital every year to follow up on the working condition of the pacemaker and the battery consumption.

I believe that in the years to come, my new friend, the pacemaker, and I will always be with you, through every spring, summer, autumn and winter.

Always protect your heart

【References】

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[3]SIDHU S, MARINE J E. Evaluating and managing bradycardia[J]. Trends Cardiovasc Med, 2020, 30(5): 265-272.

[4]DEFORGE W F. Cardiac pacemakers: a basic review of the history and current technology[J]. J Vet Cardiol, 2019, 22: 40-50.

[5] Ge Junbo, Xu Yongjian, Wang Chen. Internal Medicine[M]. 9th edition. Beijing: People's Medical Publishing House, 2018.