Heart valves are valves that ensure that the blood circulates in our body only in a forward motion. In a heart valve disease, they can either become too narrow (stenosis) or leak (insufficiency). Depending on which heart valve is affected or how the defect presents itself, the valve can be repaired (reconstruction). If recovery is not possible, the diseased heart valve is replaced. The most commonly used heart valve prostheses are either made of biological (animal) material (usually bovine pericardium), so-called biological valves, or resistant material such as titanium or carbon, so-called mechanical heart valve prostheses. Mechanical heart valve prostheses require life-long blood thinning. With biological heart valves, blood thinning is usually only necessary for a short time or not at all. Conventional heart valve surgery is an open heart operation using the heart-lung machine (HLM).

«Minimally invasive» is a broad term in cardiac surgery and can refer both to the size of the entryway as well as to the avoidance of using the heart-lung machine. For minimally invasive entryways, the surgical procedure is performed through the smallest possible opening of a few centimeters. Depending on the type of operation, this is either performed with a direct view of the operating field (e.g., aortic valve) or indirectly via visualization using endoscopic optics and screen-controlled (e.g., mitral valve). A minimally invasive procedure in bypass surgery means surgery on the beating heart without using the heart-lung machine. Appropriate stabilizers locally immobilize the area to be operated on (vascular anastomosis).

The aorta is the largest blood vessel in the human body. It emerges from the left ventricle, rises, and runs over an arch into the abdomen. Above the diaphragm, it is known as the thoracic aorta (thoracic aorta), and below as the abdominal aorta (abdominal aorta). The thoracic aorta has an ascending part (aorta ascendens) and a descending part (aorta descendens). This subdivision is essential because the localization of the disease requires different therapeutic procedures.

The most common disease of the aorta is a weakening of the vascular wall's elastic tissue, which leads to a dilatation (aneurysm) of the aorta. An aortic aneurysm can occur in all sections and involve other structures such as the aortic valve. With an aortic aneurysm, there is always the risk of an internal (dissection) or external rupture with correspondingly life-threatening bleeding complications.

In an ascending aneurysm, the diseased section of the vessel is replaced by a vascular prosthesis. Today, an aneurysm of the descending and abdominal arteries is usually stabilized by an endovascular stent prosthesis (internal vascular support). In some cases, a combination of both treatment methods is also useful.

The cardio technician works in an interdisciplinary field between cardiovascular surgery and medical technology. Depending on the location, his central task is the preparation, operation, monitoring, or further development of heart-lung machines and other medical-technical monitoring and treatment equipment.

The heart-lung machine (HLM) is a complex medical-technical device that takes over the tasks of the heart (pumping function) and lungs (enrichment of the blood with oxygen) for a limited period during open-heart surgery. The blood leaves the body via a tube system. It is returned to the body after it has been enriched with oxygen (extracorporeal circulation). With the help of the heart-lung machine, all open heart operations become possible.

A narrowing of the carotid artery (usually the internal carotid artery, ACI) carries a stroke risk. The risk of suffering a stroke due to carotid artery disease is >10% per year for higher grade stenoses. The majority of carotid stenoses are asymptomatic. Symptomatic stenosis of the internal carotid artery manifests itself as a transitory ischaemic attack (TIA, passerine paralysis, speech disorders, etc.), as amaurosis fugax (passerine blindness), or as a manifest ischaemic stroke. The classic surgical procedure is the carotid thrombendarterectomy, removing the stenosing plaques and reconstructing the vessel wall. The process is low-risk and offers excellent long-term results.

Cardiac arrhythmias require different measures depending on the type of disorder. In some instances, surgical intervention is necessary:

Atrial fibrillation: Atrial fibrillation is primarily treated with medication or with the help of an interventional catheter technique. An alternative, especially for patients who require additional cardiac surgery, is surgical ablation. Ablation creates scar tissue and thus impedes or completely blocks the faulty excitation. The sinus node takes over the control of the heart excitation again.

Sick sinus node (heart pulse generator): This impaired function of the sinus node is often caused by an unspecific scarred degeneration in the conduction system. Measure: Inserting a pacemaker

Transition disorders (AV node): The stimulus conduction between the atrium and chamber is delayed and/or partially/permanently blocked. Measure: Inserting a pacemaker

Rhythm disturbances in the heart chamber (ventricular tachycardia/ventricular fibrillation): Life-threatening, as the heart, can no longer maintain circulation. Measure: Insertion of a defibrillator or ICD (Internal Cardioverter/Defibrillator). The defibrillator (shock generator) can independently interrupt electrically circulating excitation in the heart, utilizing targeted current pulses. At the same time, the device also has all the functions of a standard pacemaker.

Unfavorable contraction of the heart in patients with severe heart failure and left bundle branch block (insufficient pumping capacity of the heart) Measure: Use of a CRT system. A CRT system is a normal pacemaker with three electrodes; one in the atrium, one in the right, and one in the left ventricle. This allows the heart to be stimulated synchronously again. The unfavorable effects of the left bundle branch block are bridged. Some devices also contain a defibrillator function.

In principle, heart and vascular surgery are associated with risks. A correct indication and a detailed examination before the procedure are therefore essential to avoid taking unnecessary risks. Due to concomitant diseases, the risks of intervention can vary in their probability. A personal consultation is essential to clarify the individual risk.