Disorders of the heartbeat: a historical overview from antiquity to the mid-20th century

Non-invasive continuous blood pressure monitoring systems: current and proposed technology issues and challenges

High blood pressure (BP) or hypertension is the single most crucial adjustable risk factor for cardiovascular diseases (CVDs) and monitoring the arterial blood pressure (ABP) is an efficient way to detect and control the prevalence of the cardiovascular health of patients. Therefore, monitoring the regulation of BP during patients' daily life plays a critical role in the ambulatory setting and the latest mobile health technology. In recent years, many studies have been conducted to explore the feasibility and performance of such techniques in the health care system. The ultimate aim of these studies is to find and develop an alternative to conventional BP monitoring by using cuff-less, easy-to-use, fast, and cost-effective devices for controlling and lowering the physical harm of CVDs to the human body. However, most of the current studies are at the prototype phase and face a range of issues and challenges to meet clinical standards. This review focuses on the description and analysis of the latest continuous and cuff-less methods along with their key challenges and barriers. Particularly, most advanced and standard technologies including pulse transit time (PTT), ultrasound, pulse arrival time (PAT), and machine learning are investigated. The accuracy, portability, and comfort of use of these technologies, and the ability to integrate to the wearable healthcare system are discussed. Finally, the future directions for further study are suggested.

A brief journey into the history of the arterial pulse

Objective. This paper illustrates the evolution of our knowledge of the arterial pulse from ancient times to the present. Several techniques for arterial pulse evaluation throughout history are discussed. Methods. Using databases including Worldcat, Pubmed, and Emory University Libraries' Catalogue, the significance of the arterial pulse is discussed in three historical eras of medicine: ancient, medieval, and modern. Summary. Techniques used over time to analyze arterial pulse and its characteristics have advanced from simple evaluation by touch to complex methodologies such as ultrasonography and plethysmography. Today's understanding of the various characteristics of the arterial pulse relies on our ancestors' observations and experiments. The pursuit of science continues to lead to major advancements in our knowledge of the arterial pulse and its application in diagnosis of atherosclerotic disease.

Wilhelm His Jr. (1863–1934)—The man behind the bundle

Wilhelm His Jr. (1863-1934) was a Swiss-born cardiologist and anatomist. In 1893, he discovered the bundle of His-the specialized tissue in the heart that transmits the electrical impulses and helps synchronize contraction. He pioneered studies in cardiac conduction and coined the term "heart block," which he identified as the cause of Adams-Stokes disease. He was a professor of medicine at the University of Berlin, became the dean of medicine in 1918 and in 1928 was elected rector of the University of Berlin. Through his long clinical and teaching career he became better known for his work on gout and diseases of the joints. "Trench fever," or Werner-His disease, was also named after him. This report presents the life and work of Wilhelm His Jr., who was described by his colleagues as "a master of his profession, a great physician, investigator, and a well cultured gentleman."

A hybrid on-line ECG segmenting system for long-term monitoring

This paper introduces a new hybrid ECG beat segmenting system, which can be applied in the processing unit of single-channel, long-term ECG monitors for the on-line segmentation of the ECG signal. Numerous ECG segmentation techniques are already existing and applied, however sufficiently robust and reliable methods currently require more than one ECG signal channel and quite complex computations, which are practically not feasible in stand-alone, low-cost monitors. Our new system approach presents a time domain segmentation technique based on a priori physiological and morphological information of the ECG beat. The segmentation is carried out after classifying the ECG beat, using the linear approximation of the filtered ECG signal and considering the pathophysiological properties as well. The proposed algorithms require moderate computational power, allowing the practical realization in battery powered stand-alone long-term cardiac monitors or small-sized cardiac defibrillators. The prototype version of the system was implemented in Matlab. The test and evaluation of the system was carried out with the help of reference signal databases.

Chest pain, palpitations and panic

Chest pain and palpitations are commonly described in the general population and are frequent presenting symptoms in all medical settings. Although often transient, they can be persistent and are associated with considerable disability, distress, and concern about heart disease and use of medical resources. Both symptoms are associated with panic but also with other psychiatric disorders. It is most useful to consider etiology as multicausal and interactive; psychological factors affect interpretation of bodily perceptions and have deleterious effects on quality of life and use of medical resources. There is evidence that general measures and specific drug and psychological treatments can be effective. There is still uncertainty about the most appropriate ways of providing effective care to large numbers of patients.

A history of the origin, evolution, and impact of electrocardiography

The invention of the electrocardiograph by Dutch physiologist Willem Einthoven in 1902 gave physicians a powerful tool to help them diagnose various forms of heart disease, especially arrhythmias and acute myocardial infarction. The discovery of x-rays in 1895 and the invention of the electrocardiograph 7 years later inaugurated a new era in which various machines and technical procedures gradually replaced the physician's unaided senses and the stethoscope as the primary tools of cardiac diagnosis. These sophisticated new approaches provided objective information about the structure and function of the heart in health and disease. This review summarizes the origins and development of electrocardiography and addresses its role in defining cardiology as a specialty.