## 4 Discussion  
In the analysis carried out during the search, a large number of patents with interesting operating principles were detected, but which for unknown reasons have been abandoned, such as, for example, the US patent 2017/0065194A1 \"Cardiovascular Detection System And Method\" [55], which establishes an analysis of the ECG to determine the presence of cardiovascular risk, and the US patent US 2014/0194758 A1 \"System and method for evaluating an electrophysiological signal\" [56], which performs a reconstruction of the electrocardiographic signal derived from a non-transitory model, which through the team manages to identify the pathological event and carry out a reconstruction of the event. It was also observed that the majority of patents correspond to companies that make improvements to existing models. In the case of patents developed by universities and their research departments, although their designs are present, they are not available in the market, and the information available in this regard is only that provided in the patent documents. The causes of this lack of information flow and follow-up to the product of the accepted and current patents are unknown. The patents obtained can be classified into four groups, depending on their operation. The first group corresponds to the analysis and reconstruction of ECG signals. The patents that make up this group are the following: 3.4, 3.5, 3.6, 3.8, 3.10, 3.14, 3.18, 3.22, 3.25, 3.27, and 3.30. Analyzing and reconstructing the signals facilitates their study, and with the information collected, patient data can be created through a simulation. This avoids the need to send the patients for medical analysis again. In this way, various behavioral scenarios are proposed, either, generating future cases if the circumstances that led to that failure are followed, or the implementation of treatment possibilities, such as surgery, medications and pacemaker. The second group corresponds to the patents that function as support for the treatments, which we find are: 3.1, 3.9, 3.16, and 3.21. This group of patents is the smallest in quantity, in its favor, in addition to providing an analysis of the patient's condition, it allows treatments to be used depending on the type of CVD that the patient presents. This supports a higher success rate in addition to subsequent revisions. The third group is of the patents that identify abnormal rhythm patterns, that is, identify arrhythmias, based on the normal values of the ECG tracing. These patents are: 3.1, 3.2, 3.4, 3.5, 3.8, 3.9, 3.10, 3.11, 3.13, 3.15, 3.16, 3.19, 3.20, 3.21, 3.24, 3.26, 3.29, and 3.30. This is the largest group in the number of patents, and the advantage they present in the diagnosis is that they provide a more specific analysis to this group of pathologies, which are considered silent since their existence is not known until severe symptoms appear in the patient. Being able to identify abnormal rhythm patterns in the early stages guarantees recovery in the shortest time, in addition to being a tool that is easy to acquire and use. The fourth group consists of the patents: 3.3, 3.7, 3.12, 3.15, 3.17, 3.21, 3.23, and 3.28. These, in addition to taking into account ECG data, are supported by accelerometers, and also consider risk factors, as well as other physiological measurements, such as heart rate, blood pressure, and fluid dynamics. This type of measurement gives a more general overview of the patient's condition since it allows for evaluating the consequences that may occur in the rest of the body caused by CVD. Although the patents were divided into four groups based on the function they present, there were some that were part of two or more groups, due to the variety they present in their functions. This reflects the same variability that CVDs present, which must be seen from different points of view to make a more complete analysis, not only to diagnose but also to include treatment and follow-up.