3D iterative reconstruction can do so much more than reduce dose.

Recent advances in software and hardware for cardiac SPECT have the potential to revolutionize nuclear cardiology. It is easy to use these technologies to maintain the status quo and lower radiation dose, despite the fact there is very little evidence that lowering patient dose in already low dose imaging protocols confers any benefit to patients. Cardiac SPECT has tremendous potential for risk stratification, molecular tracers, and high temporal resolution management of patients with electrophysiological disorders. In addition, these new reconstruction techniques can offer spatial resolution that is comparable and sometimes even superior to PET. Lastly, recent research has also held out the potential for performing absolute blood flow qualification using SPECT instrumentation. As these new technologies become available, the goal should be to make images better and improve patient care first, then optimize the dose.

Using Flexible Curved Noncontact Active Electrodes to Monitor Long-Term Heart Rate Variability.

The purpose of this study is to utilize flexible curved noncontact active electrodes to develop a nonperception, long-term, and wireless heart rate monitoring system. This study also verified the functions and capabilities of the system and provided information on physiological parameters recorded during our tests. Our system was used in tandem with a commercially standard measurement system; both systems were used to measure ECG signals on 10 healthy subjects under the simulated home and office scenarios. We verified the R-peak measurement accuracy of our system and used T-tests to analyze the data collected by both systems; our system reached an average sensitivity value of 0.983 and an average positive predictive value of 0.991 over several different scenarios where R-peak measurements were also highly accurate. The R-R time intervals of our system were highly consistent with the standard system. The correlation coefficient calculated reached almost one, and the differences between the two systems mostly fell within the ±10 ms range. Further study of the HRV time-domain parameters under four different scenarios showed no significant differences in most HRV parameters compared to the measurements by the standard system. We also used our system to record long-term heart rate signals.

Balram Bhargava: catalysing innovation.

Balram Bhargava talks with Sophie Cousins about fostering affordable, need-driven innovation.

Catheter steering in interventional cardiology: Mechanical analysis and novel solution.

In recent years, steerable catheters have been developed to combat the effects of the dynamic cardiac environment. Mechanically actuated steerable catheters appear the most in the clinical setting; however, they are bound to a number of mechanical limitations. The aim of this research is to gain insight in these limitations and use this information to develop a new prototype of a catheter with increased steerability. The main limitations in mechanically steerable catheters are identified and analysed, after which requirements and solutions are defined to design a multi-steerable catheter. Finally, a prototype is built and a proof-of-concept test is carried out to analyse the steering functions. The mechanical analysis results in the identification of five limitations: (1) low torsion, (2) shaft shortening, (3) high unpredictable friction, (4) coupled tip-shaft movements, and (5) complex cardiac environment. Solutions are found to each of the limitations and result in the design of a novel multi-steerable catheter with four degrees of freedom. A prototype is developed which allows the dual-segmented tip to be steered over multiple planes and in multiple directions, allowing a range of complex motions including S-shaped curves and circular movements. A detailed analysis of limitations underlying mechanically steerable catheters has led to a new design for a multi-steerable catheter for complex cardiac interventions. The four integrated degrees of freedom provide a high variability of tip directions, and repetition of the bending angle is relatively simple and reliable. The ability to steer inside the heart with a variety of complex shaped curves may potentially change conventional approaches in interventional cardiology towards more patient-specific and lower complexity procedures. Future directions are headed towards further design optimizations and the experimental validation of the prototype.

The association of imaging equipment age with other quality metrics and successful laboratory accreditation by the Intersocietal Accreditation Commission.

BACKGROUND: Intersocietal Accreditation Commission (IAC) accreditation is granted or delayed depending on the fulfillment of several quality metrics. Investing in up-to-date equipment might reflect a commitment to quality. METHODS: Data from echocardiography (n = 3079) and nuclear cardiology (n = 1835) accreditation applications submitted between 2012 and 2014 were evaluated to determine the mean age of laboratory equipment. Laboratory quality was assessed by the number of missing quality metrics, and a composite quality score was calculated as the sum of missing quality metrics. A lower score thus represented better laboratory quality. The relationship between equipment age and quality was explored as an interaction term between equipment age and the composite quality score and was incorporated into regression models for prediction of accreditation status. RESULTS: During the study period, 49% of echocardiography and 42% of nuclear laboratories were granted accreditation without delay. For both echocardiography and nuclear laboratories, there was a statistically significant trend toward an increasing number of missing quality metrics with increasing quartiles of equipment age. The interaction between equipment age and the composite quality score was a significant predictor of delay of accreditation for both echocardiography and nuclear cardiology laboratories, with a stronger association for 1st-time applicants. Among sites applying for accreditation in both modalities simultaneously, accreditation in one modality predicted the accreditation decision for the other. CONCLUSIONS: Laboratory quality is an important determinant of IAC accreditation, and equipment age is an effect modifier of this relationship. Contemporary equipment likely reflects a commitment to quality, for both echocardiography and nuclear laboratories.

Smartphone-Based Device in Exotic Pet Medicine.

This article reviews the use of the smartphone in exotic pet medicine. The mobile app is the most instinctive use of the smartphone; however, there are very limited software dedicated to the exotic pet specifically. With an adapter, the smartphone can be attached to a regular endoscope and acts as a small endoscopic unit. Additional devices, such as infrared thermography or ultrasound, can be connected to the smartphone through the micro-USB port. The medical use of the smartphone is still in its infancy in veterinary medicine but can bring several solutions to the exotic pet practitioner and improve point-of-care evaluation.

Evaluating the Performance of Cardiac Pulse Duplicators Through the Concept of Fidelity.

INTRODUCTION: The advanced design techniques used in modern prosthetic heart valve (PHV) development require accurate replication of the entire cardiac cycle. While cardiac pulse duplicator (CPD) design has a direct impact on the PHV test data generated, no clear guidelines exist to evaluate the CPD's performance. In response to this, we present a method to quantitatively assess CPD performance. MATERIALS AND METHODS: A method to establish the fidelity of CPDs was formulated based on the pressure/time relationship and the error related to this relationship's target. This method was applied to assess the performance of a custom-made CPD. The performance evaluation included the assessment of the motion control system and overall repeatability of pressure measurements using a St Jude Epic 21 mm aortic valve. RESULTS: The CPD's motion control system had an average root mean square error (RMSE) beat-to-beat tracking accuracy of 0.046 ± 0.008 mm. Assessment of the pressure measurements yielded a repeatability of < 2.4 ± 0.9 mmHg RMSE beat-to-beat differential pressure. The combination of pressure and its location within a heartbeat (fidelity) was within 5.0% of the individual targets for at least 95% of heartbeats. CONCLUSION: Fidelity can be used to objectively quantify the performance of various aspects of CPDs and to identify the cause of unexpected PHV or CPD behaviour. It also enables comparisons to be made among various CPDs in terms of overall performance. This approach may enable standardization of the assessment of CPD performance in the future.

Advances in imaging instrumentation for nuclear cardiology.

Advances in imaging instrumentation and technology have greatly contributed to nuclear cardiology. Dedicated cardiac SPECT cameras incorporating novel, highly efficient detector, collimator, and system designs have emerged with the expansion of nuclear cardiology. Solid-state radiation detectors incorporating cadmium zinc telluride, which directly convert radiation to electrical signals and yield improved energy resolution and spatial resolution and enhanced count sensitivity geometries, are increasingly gaining favor as the detector of choice for application in dedicated cardiac SPECT systems. Additionally, hybrid imaging systems in which SPECT and PET are combined with X-ray CT are currently widely used, with PET/MRI hybrid systems having also been recently introduced. The improved quantitative SPECT/CT has the potential to measure the absolute quantification of myocardial blood flow and flow reserve. Rapid development of silicon photomultipliers leads to enhancement in PET image quality and count rates. In addition, the reduction of emission-transmission mismatch artifacts via application of accurate time-of-flight information, and cardiac motion de-blurring aided by anatomical images, are emerging techniques for further improvement of cardiac PET. This article reviews recent advances such as these in nuclear cardiology imaging instrumentation and technology, and the corresponding diagnostic benefits.

Systematic mapping study of data mining-based empirical studies in cardiology.

Data mining provides the methodology and technology to transform huge amount of data into useful information for decision making. It is a powerful process to extract knowledge and discover new patterns embedded in large data sets. Data mining has been increasingly used in medicine, particularly in cardiology. In fact, data mining applications can greatly benefits all parts involved in cardiology such as patients, cardiologists and nurses. This article aims to perform a systematic mapping study so as to analyze and synthesize empirical studies on the application of data mining techniques in cardiology. A total of 142 articles published between 2000 and 2015 were therefore selected, studied and analyzed according to the four following criteria: year and channel of publication, research type, medical task and empirical type. The results of this mapping study are discussed and a list of recommendations for researchers and cardiologists is provided.

Transradial access: lessons learned from cardiology.

Innovations in interventional cardiology historically predate those in neuro-intervention. As such, studying trends in interventional cardiology can be useful in exploring avenues to optimise neuro-interventional techniques. One such cardiology innovation has been the steady conversion of arterial puncture sites from transfemoral access (TFA) to transradial access (TRA), a paradigm shift supported by safety benefits for patients. While neuro-intervention has unique anatomical challenges, the access itself is identical. As such, examining the extensive cardiology literature on the radial approach has the potential to offer valuable lessons for the neuro-interventionalist audience who may be unfamiliar with this body of work. Therefore, we present here a report, particularly for neuro-interventionalists, regarding the best practices for TRA by reviewing the relevant cardiology literature. We focused our review on the data most relevant to our audience, namely that surrounding the access itself. By reviewing the cardiology literature on metrics such as safety profiles, cost and patient satisfaction differences between TFA and TRA, as well as examining the technical nuances of the procedure and post-procedural care, we hope to give physicians treating complex cerebrovascular disease a broader data-driven understanding of TRA.

Wearable technology for cardiology: An update and framework for the future.

The field of cardiology has long used wearable medical devices to monitor heart rate and rhythm. The past decade has seen the emergence of many new wearable devices, including several that have been widely adopted by both physicians and consumers. In this review, we discuss existing and forthcoming devices designed to measure activity, heart rate, heart rhythm, and thoracic fluid. We also offer several frameworks to classify and better understand wearable devices, such that we may weigh their potential benefit in improving healthcare with the many challenges that must be addressed to reap these benefits.

The Liebau phenomenon: a translational approach to new paradigms of CSF circulation and related flow disturbances.

PURPOSE: The aim of the study is to provide a comparison between Liebau's effect, underlying the working principles of impedance pumps, and the cerebrospinal fluid (CSF) circulation. METHODS: Gerhard Liebau was a cardiologist with a specific interest in severe aortic regurgitation. Such interest drew his scientific attention to the flow-driven efficiency of valveless pumps. During one of his experiments, he assembled two rubber tubes of different sizes and documented how water could be aspirated against gravity when the tube of larger diameter underwent rhythmic compression. He subsequently tested an elastic tube connected to glass pipes of the same size on both ends, immersed in a water bucket. When the elastic tube was periodically pumped with a finger, a net flow could be observed in both directions; depending on the pumping site on the elastic tube, the flow was directed towards the most closely connected glass tube. The principles of a hydraulic system of different elasticity and compliance were also recently applied to the physiology and fluid dynamics of embryonic hearts. RESULTS: Impedance pumps and the CSF dynamics model are both valveless systems and can both be activated by the effects of the cardiac cycle. The novel hydraulic model of impedance pumps was the foundation for the development of modern valveless micropumps and contributes to explain how the embryonic valveless tubular heart is capable of generating blood flow. CONCLUSIONS: Liebau's effect and the mechanism of impedance pumps can enlighten some of the aspects of CSF dynamics and related flow disturbances.