Symptoms
When a bypass is necessary, deposits have caused narrowing or blockage of arteries supplying the heart. The first symptoms of a cardiovascular constriction usually occur during exercise and are chest pressure, shortness of breath and shortness of breath, irregular pulse and reduced performance. If it is a severe vasoconstriction in the arterial system of the heart, the symptoms already occur at rest.
Often, corresponding risk factors for vasoconstriction can be identified in patients. These include smoking, overweight, high blood pressure and concomitant diseases such as diabetes mellitus. In most cases, the patients state that they were able to climb stairs a few months ago and now have symptoms at rest. If a vessel is completely blocked, this corresponds to a heart attack with severe pain in the chest, radiation in the jaw and/or left shoulder, shortness of breath and sweating. A heart attack is an absolute emergency that must be treated as soon as possible.
The operation
In the past, bypass surgery was always performed on the open heart. Here the heart was stopped (cardioplegia) and the blood supply to the body was taken over by a heart-lung machine. This technique is still frequently used today.
Bypass surgery on an open, but beating heart is a variation of this. Here, no heart-lung machine is required and the bypass is performed on the beating heart. This measure is usually taken when the vessels and the aorta are so severely calcified that it is not possible to disconnect them and thus put on the heart-lung machine.
Nowadays, minimally invasive bypass surgery is also becoming more and more popular, i.e. the operation is no longer performed on the open heart and the chest remains closed. Instead, the operation is performed through a small incision between the ribs (keyhole technique). When using artificial heart valves, this gentle surgical technique has already become established and is now performed regularly.
The advantage of the minimally invasive surgical technique is that it is gentler and complications such as wound healing disorders occur less frequently. However, during the course of the operation it may become necessary to perform the operation on the open heart due to anatomical conditions (poor visibility, etc.). In this case, the keyhole method that was initially started is discontinued and the chest is opened.
Bypasses using the conventional open method and the newer keyhole method do not differ significantly in the results. With the open surgical method, in addition to wound healing disorders, inflammation of the sternum can also occur. In contrast, with the minimally invasive keyhole technique, the ribs have to be spread many times over because of the smaller access, which as side effects can probably lead to more pain in the postoperative treatment.
In 2002, just 1% of all bypass operations were performed with the keyhole technique. The proportion of minimally invasive operations has increased in the meantime, but has not yet replaced open heart surgery. According to the scientists, this is because the advantages of a minimally invasive technique over open surgery are not as convincing as hoped.
Due to the low complication rate in operations on the standing heart, the minimally invasive surgical method can also score only marginally in this aspect. Where it clearly leads, however, is the cosmetic result. While the open bypass operation leaves a wound with a subsequent scar of about 30 to 40 cm on the sternum, the minimally invasive technique leaves only a scar of a few centimetres.
A bypass operation becomes necessary if one or more coronary vessels are blocked. During the operation, a substitute vessel from the body (a vein from the lower leg or an artery from the arm) is used as a bypass. The vessel is connected to the aorta before the blockage and is reconnected to the affected coronary vessel behind the blockage.
This creates a bypass that ensures the supply of the heart muscle behind it. Every bypass operation is performed under general anaesthetic. In standard surgery, the chest is opened first, as this is the only way to ensure access to the heart.
The patient is connected to a heart-lung machine, which can replace the heart for a certain period of time. Since surgery on a beating heart is extremely difficult, the heart is immobilised with medication. Newer surgical techniques allow for bypass surgery without opening the chest.
It is also not always necessary to use the heart-lung machine. If it is not used, the bypass must first be attached to the blocked coronary artery. Then the aorta is partially clamped off and the bypass sutured.
Then the clamp is removed again. The duration of the operation is usually about three hours if the standard surgical procedure is used. A similar duration can also be assumed for the minimally invasive surgical techniques.
In general, the duration of the operation depends on how many bypasses are to be constructed. On the one hand, each bypass requires additional time for the removal of the vessel on the arm or leg. Especially when several bypasses are used from different parts of the body, the surgery time is extended.
Furthermore, depending on the location, the “fitting” of the bypass on the heart is also time-consuming. For example, it is more difficult to get to the back of the heart, which is why a bypass at this location takes longer than a bypass at the front wall. The duration of the operation can also include preparation and follow-up.
As a rule, medication is administered about one hour before the operation, which makes you tired and has a calming effect. The surgery itself then begins with the induction of general anesthesia, after which the operation can be performed on the heart. It usually takes another 10 to 30 minutes before the patient awakens from the anaesthesia after the operation.
While the minimally invasive use of a stent costs about 17,000 EUR, a bypass operation can cost up to 30,000 EUR. The cost difference of the pure surgical method is small, but due to the somewhat longer post-operative treatment of an open surgery (wound care, drainage insert, etc.) the costs can be higher.
On the other hand, the more complicated training methods with which surgeons specialize in keyhole surgery techniques are cost-intensive. Here, a surgical robot is required, the cost of which is around EUR 1 million and which not every centre can afford. The training costs for minimally invasive surgery are therefore currently much higher, which makes the costs for open bypass surgery comparatively lower.
Another disadvantage of the minimally invasive method is the more precise and demanding monitoring of the patient during the procedure. Since the operation is performed on the beating heart, special attention must be paid to possible irregularities in the circulatory system during the procedure. The risk of injury to vessels and/or nerve cords during the procedure is also described as increased with the keyhole technique, as the heart surgeon lacks the usual view of the open surgical field.
With the open surgical method, however, wound healing disorders and complications due to the massive opening and spreading of the chest occur more frequently. Despite the almost identical results with open and minimally invasive bypass surgery, it should be noted that although several narrow areas can be bridged with the keyhole technique, not 4-5 as with open surgery. Critics point out that minimally invasive bypass surgery reaches its limits here, as a large number of constrictions make bypass surgery necessary. The operation on the standing heart takes about 3-6 hours, depending on the vessels to be operated and the general condition of the patient. The duration of the minimally invasive surgical technique is somewhat shorter due to the omission of the chest opening and the connection of the heart-lung machine.
