The right atrial auricle-Worthy of a new look

INTRODUCTION

The right atrium is the least well studied cardiac chamber. Even less is known about the right atrial appendage (RAA). Recently, the RAA has been shown to be the site of numerous and diverse pathological processes. Furthermore, the RAA can also be the site of origin of atrial fibrillation with obvious implications for ablation procedures. No standard method of transthoracic echocardiography (TTE) for imaging of the RAA can be found in current literature, despite numerous reports for transesophageal echocardiography (TEE).

PURPOSE OF THIS STUDY

The purpose of this study was to determine if a reliable transthoracic window could be found for consistent and reliable imaging of the RAA.

METHOD

30 patients (15 men and 15 women) were included into this study. All patients were placed in the left lateral decubitus position and echocardiography was performed with a Vivid E9 ultrasound system (GE Healthcare). The RAA was visualized by tilting the probe infero-medially from the standard apical four chamber view.

RESULTS

The RAA was visualized in all 30 patients. The RAA followed a consistent upwards and leftwards path anterior to the aortic root.

CONCLUSION

TTE is a valid method of imaging of the RAA.

Budget Impact Analysis of Empagliflozin in the Treatment of Patients With Type 2 Diabetes With Established Cardiovascular Disease in South Africa

OBJECTIVES

This study aimed to estimate the budget impact and affordability of empagliflozin added to usual care compared with usual care alone, in a diabetic population with established cardiovascular disease, from a private healthcare payer perspective in South Africa.

METHODS

A budget impact model was adapted and localized. Epidemiological data were obtained from the South African Council for Medical Schemes. Clinical event rates were sourced from the EMPA-REG OUTCOME trial and drug costs from list prices. Clinical event costs were derived from a claims data analysis of the South African private healthcare sector and microcosting. Scenario analyses were performed on select inputs. The modeled outcomes included annual budget impact of empagliflozin, the incremental cost per life per month, cardiovascular deaths averted, and incremental cost per life saved, over 3 years.

RESULTS

A total of 9 503 patients were eligible for empagliflozin (year 1), 12 670 (year 2), and 16 947 (year 3). The incremental cost was $1 272 297, $1 764 705, and $2 455 235, for years 1 to 3, respectively. The incremental cost per beneficiary per month was calculated as $0.012 (year 1), $0.016 (year 2), and $0.023 (year 3). The model estimated a 38.6% reduction in cardiovascular deaths, 305 lives saved, and an incremental cost per life saved of $17 999.

CONCLUSIONS

Adding empagliflozin to usual care has a marginal budget implication and is highly affordable for private healthcare payers, with an acceptable incremental cost based on clinical outcomes.

Walking in a straight line–the early detection of cardiomyopathy by the general physician

Introduction

The orientation of muscle fibers in the left ventricle is sophisticated. This peculiar orientation causes the left ventricle to contract in three directions–longitudinal, radial and circumferential. Normal myocardial mechanics is essential for systolic and diastolic function. For the clinician an impairment in longitudinal function is of utmost importance, as it has been shown to be an early marker of left ventricular dysfunction, be that systolic or diastolic. Longitudinal function of the left ventricle can be quantified with tissue velocity imaging (TVI), mitral annular plane systolic excursion (MAPSE) and global longitudinal strain (GLS), as measured by speckle-tracking.

GLS measured by speckle-tracking is more technically challenging than measuring MAPSE and furthermore, in a setting with limited resources, not always widely available. Surprisingly, there is a paucity of data on the correlation of GLS to MAPSE. As GLS is the latest modality used to quantify longitudinal function of the LV and TVI is also more technically challenging than MAPSE, MAPSE was the chosen modality to compare to GLS. Furthermore, not all echocardiography systems are equipped for TVI and GLS, whereas that is not the case for MAPSE. MAPSE is therefore an easily acquired skill and widely available.

Purpose of this study

To determine whether MAPSE, when compared to GLS, is an accurate way to quantify longitudinal function of the left ventricle. If this is shown to be the case, then MAPSE will be a proven, readlily available and easily acquired skill to detect cardiomyopathy, whether primary or secondary to a wide variety of systemic diseases.

Methods

175 patients who presented with a variety of primary cardiac diseases and/or systemic diseases with the potential for cardiac involvement were included into the study.

175 patients with normal cardiac function were also included into the study.

Left ventricular longitudinal function of the left ventricle was quantified in each patient by means of MAPSE, as well as GLS measured by speckle-tracking. In order to correct MAPSE to body size, MAPSE:LV length was measured.

The correlation of MAPSE with GLS was assessed by means of a two-by-two table.

Results

In this group of 350 patients, split into 2 equal groups-175 with cardiomyopathy, either primary or secondary due to systemic disease, and 175 with no cardiomyopathy, the distinction is clear. The exposore, a GLS <−20% and a MAPSE:LV-lenghth <20% versus no exposure – a GLS <−20% and a MAPSE: LV-length >20% leads to a likelihood ratio of 485 (p=0) and a Pearson correlation of 525 (p=0) that impaired LV-longitudinal function is present.

Conclusion

A MAPSE: LV-length <20% correlates reliably with an impaired GLS. This is a reliable substitute for GLS and for the general physician who screens for early cardiomyopathy this is a skill that will be cheaper and more easily learned than GLS.

Funding Acknowledgement

Type of funding sources: None. GLSMAPSE

Pelvic kidney as a cause of May-Thurner syndrome

Deep venous thrombosis is a common clinical problem with significant morbidity and mortality. Since the iconic publication by Virchow in 1856, which placed all known causes of deep venous thrombosis into three groups, namely venous stasis, vascular injury and hypercoagulability, numerous causes have been added to each category. This case report highlights the importance of an anatomical imaging study of the pelvis in cases of recurring, proximal deep venous thrombosis of the lower limb.

Unilateral atrial fibrillation - how common is atrial divorce?

Atrial fibrillation is the most common pathologic supraventricular tachycardia. It has many causes, is an expensive disease, impairs quality of life and leads to an increased risk of death. Atrial dissociation is characterised by the presence of two independent sets of P-waves. This peculiar abnormality may give rise to the scenario where one atrium is in atrial fibrillation while the other is in sinus rhythm. This is the first published case of atrial dissociation where the phenomenon is demonstrated by transmitral and transtricuspid pulsed wave Doppler.

Solitary Papillary Muscle Hypertrophy: A New Echo-Electrocardiographic Syndrome? A Case Report

Hypertrophic cardiomyopathy is the term for a heterogeneous group of disorders for which various mutations of genes involving proteins of the cardiac sarcomere lead to hypertrophy of various segments of the left ventricle. The hypertrophy can involve the left and/or right ventricle, be symmetric or asymmetric, involving the septum, free wall, mid-ventricle, or apex. The phenomenon of solitary papillary muscle hypertrophy is rare with only 2 references in the literature. Furthermore, giant negative T and U waves are 2 common electrocardiographic phenomena in hypertrophic cardiomyopathy and have been attributed to hypertrophy of the posterior papillary muscle. Solitary hypertrophy of the anterior papillary muscle might be a new echo-electrocardiographic syndrome.

'Trochars no more': Teaching chest drain insertion to remote and rural practitioners using a mobile skills unit

BACKGROUND

There are a number of approaches to teaching high-risk clinical skills, such as a large bore chest drain insertion, although effectiveness is limited and realism is only achieved at great expense. Summary of work: In response to a training needs' analysis of practitioners in remote and rural areas in Scotland, training in chest drains was identified as an urgent priority need. Subsequently, the Clinical Skills Managed Educational Network (CSMEN) developed an evidence-based multi-professional clinical skills pack. This e-learning resource encompasses all aspects of chest drain management, both pre and in-hospital. The pack and an interactive workshop is used to deliver 'blended' chest drain training on a mobile clinical skills unit. Evaluation confirms that the chest drain training is a valuable resource and has been widely used to deliver skills training in remote and rural areas. Feedback from all professional groups is positive.

CONCLUSIONS

Developing shared national resources, with standardised workshops taught in local contexts via a mobile skills unit is one approach to the challenges associated with delivering high-risk clinical skills education.

The Kuwait-Scotland eHealth Innovation Network (KSeHIN): a sustainable approach to quality improvement in healthcare

BACKGROUND

The rising prevalence of obesity and diabetes in Kuwait represents a significant challenge for the country's healthcare system. Diabetes care in Scotland has improved by adopting a system of managed clinical networks supported by a national informatics platform. In 2010, a Kuwait-Dundee collaboration was established with a view to transforming diabetes care in Kuwait. This paper describes the significant progress that has been made to date.

METHODS

The Kuwait-Scotland eHealth Innovation Network (KSeHIN) is a partnership among health, education, industry and government. KSeHIN aims to deliver a package of clinical service development, education (including a formal postgraduate programme and continuing professional development) and research underpinned by a comprehensive informatics system.

RESULTS

The informatics system includes a disease registry for children and adults with diabetes. At the patient level, the system provides an overview of clinical and operational data. At the population level, users view key performance indicators based on national standards of diabetes care established by KSeHIN. The national childhood registry (CODeR) accumulates approximately 300 children a year. The adult registry (KHN), implemented in four primary healthcare centres in 2013, has approximately 4000 registered patients, most of whom are not yet meeting national clinical targets. A credit-bearing postgraduate educational programme provides module-based teaching and workplace-based projects. In addition, a new clinical skills centre provides simulator-based training. Over 150 masters students from throughout Kuwait are enrolled and over 400 work-based projects have been completed to date.

CONCLUSION

KSeHIN represents a successful collaboration between multiple stakeholders working across traditional boundaries. It is targeting patient outcomes, system performance and professional development to provide a sustainable transformation in the quality of diabetes healthcare for the growing population of Kuwaitis with diabetes in Kuwait.

Thyroxine and cardiac electrophysiology-a forgotten physiological duo?

Thyroid hormone exerts numerous effects on the cardiovascular system. Hypothyroidism can lead to various electrocardiographic and mechanical changes in the heart and blood vessels.

The potential risk for sudden cardiac death in patients with hypothyroidism have never been properly explored. However, numerous reports of various electrocardiographic changes indicative of such a risk has been published.

In this case report the occurrence of ventricular late potentials in a case of overt hypothyroidism is described and furthermore, the disappearance of these potentials with T4 treatment alone is shown.

It is concluded that the concept that undiagnosed and/or untreated hypothyroidism poses a risk for sudden cardiac death is worth exploring.

Cardiovascular pharmacogenetics

Human genetic variation in the form of single nucleotide polymorphisms as well as more complex structural variations such as insertions, deletions and copy number variants, is partially responsible for the clinical variation seen in response to pharmacotherapeutic drugs. This affects the likelihood of experiencing adverse drug reactions and also of achieving therapeutic success. In this paper, we review key studies in cardiovascular pharmacogenetics that reveal genetic variations underlying the outcomes of drug treatment in cardiovascular disease. Examples of genetic associations with drug efficacy and toxicity are described, including the roles of genetic variability in pharmacokinetics (e.g. drug metabolizing enzymes) and pharmacodynamics (e.g. drug targets). These findings have functional implications that could lead to the development of genetic tests aimed at minimizing drug toxicity and optimizing drug efficacy in cardiovascular medicine.

A brief report on perceptions of alcohol and society among Scottish medical students

AIMS

To assess perceptions on alcohol misuse and addiction among medical students prior to in-depth training in order to determine areas of the curriculum that need to be reshaped or focused on.

METHODS

A questionnaire assessment of first- and second-year medical students' perceptions of alcohol misuse.

RESULTS

Students had some misconceptions about current alcohol misuse rates, including a perception that addiction is common among health professionals, that the under-25s had the fastest increasing rate of alcohol addiction and that British women had a more rapidly increasing rate of alcohol addiction than British men.

CONCLUSION

Encouragingly, students overwhelmingly felt that alcohol addiction was something to which they could make a difference. It highlights that early education about alcohol misuse is important in terms of teaching students how to recognize hazardous and harmful drinkers and how to manage them.

Hypertension and its management in countries in Africa and the Middle East, with special reference to the place of β-blockade

BACKGROUND

The prevalence and clinical consequences of hypertension in countries in Africa and the Middle East have not been studied as well as in other regions.

SCOPE

We have reviewed the literature on the epidemiology and management of hypertension and related cardiovascular complications in countries within Africa and the Middle East. A PubMed search for countries in the region and 'hypertension' was supplemented by articles identified from reviews, and by literature suggested by the authors.

FINDINGS

The prevalence of hypertension is >20% in some countries in the Middle East and Africa, despite an average population age that is some 10-15 years lower than those of developed countries. Hypertension in these countries is associated with an increased risk of cardiovascular risk factors and cardiovascular disease, as elsewhere. Awareness rates of hypertension are low. Hypertension and its complications are undertreated, and mortality rates from cardiovascular disease are higher than in developed countries.

CONCLUSION

Available resources should be brought to bear on the management of hypertension in these countries. In particular, a recent downgrading of the importance of β-blockers in hypertension management guidelines needs to be reassessed. These agents are as effective as other antihypertensive classes both on blood pressures and on cardiovascular event rates. General concerns over an increased rate of new-onset diabetes with β-blockers have been overstated, although these agents should be avoided in metabolic syndrome.

Subendocardial fibrosis in left ventricular hypertrabeculation-cause or consequence?

Left ventricular noncompaction has been classified as a primary cardiomyopathy with a genetic origin. This condition is morphologically characterized by a thickened, two-layered myocardium with numerous prominent trabeculations and deep, intertrabecular recesses. Recently, it has become clear that these pathological characteristics extend across a continuum with left ventricular hypertrabeculation at one end of the spectrum.

The histological findings include areas of interstitial fibrosis.

We present a case of left ventricular hypertrabeculation which presented as sudden infant death syndrome. Histologically areas of subendocardial fibrosis was prominent and we propose that this entity may be a hidden cause of arrhythmic death in some infants presenting as sudden infant death syndrome., with areas of subendocardial fibrosis as possible arrhythmogenic foci.

Sudden infant death syndrome and left ventricular hypertrabeculation-hidden arrhythmogenic entity?

Left ventricular noncompaction/hypertrabeculation is a condition which is characterized by a highly trabeculated, “spongy” myocardium.

It can present at any age with heart failure, arrhythmia and/or thromboembolic events.

A wide variety of mutations have been found to be a cause of hypertrabeculation and it is possible that there is a continuum of hypertrophic cardiomyopathy, dilated cardiomyopathy and hypertrabeculation/noncompaction.

We present a case of left ventricular hypertrabeculation which presented as sudden infant death syndrome and we propose that this entity may be a hidden cause of arrhythmic death in some infants presenting as sudden infant death syndrome.

Subaortic (type 6) muscular band-innocent bystander or pathologic structure?

Intraventricular tendons are structures that was identified more than a hundred years ago. It has been suggested that they represent intracavitary radiations of the bundle of His and that they may be an isolated finding or be associated with structural cardiac abnormalities.Loukas et al divided these structures into five categories and recently a sixth type have been added.Various physiological disturbances have been observed due to the sixth type of tendon, such as ST segment elevation and right bundle branch block. It has been noted that this peculiar structure appears too thick to be called a tendon, thus the term band.This retrospective analysis analyzed the incidence of the thick, subaortic (type 6) muscular band in a cardiovascular clinic.

The liver and right atrium-hepatic cyst as a cause of arrhythmia

Simple hepatic cysts are a relatively common radiological finding. These cysts may be classified as parasitic and non-parasitic. They are usually asymptomatic, but may cause symptoms due to local compression. These compressive complications include: portal hypertension, edema due to caval compression, extrinsic gastric compression and duodenal compression with obstruction.

However, no reports in the literature exist describing atrial compression by hepatic cysts.

In this case report a simple hepatic cyst causing slight right atrial compression is described. This slight compression is the cause of atrial premature beats.

It is proposed that simple hepatic cysts may be the cause of atrial premature beats.

Post-mortem echocardiography as a guide to cardiac autopsy-a worthwhile concept?

Sudden and unexpected death in the young is a common and worldwide problem. Sudden, unexpected death in infancy (SUDI), clinically unexpected death in an infant between one week and one year of age, affects around 1 in 1000 infants. Autopsy will reveal a specific cause of death in only one third of cases. This has led to various ancillary examinations in an effort to increase the diagnostic yield of the autopsy.

In this case report it is suggested that another diagnostic modality, that of the post-mortem echocardiogram might be a worthwhile concept to explore.

Right ventricular variants and pulmonary embolism-association or coincidence?

It has been stated that the interior of the right ventricle is as unique to each individual as one’s fingerprint. This statement is backed by numerous publications which demonstrates considerable variation in the number, shape and configuration of papillary muscles inside the normal right ventricle.

It has also been shown that these variants may be the cause of cardiac rhythm disorders.

In this case report another potential complication of such right ventricular papillary muscle variants is proposed—these muscles may be the source of pulmonary emboli.

The pathogenesis may be that of local stasis around these aberrant muscular structures and/or emboli may form inside the right ventricle as a result of cardiac rhythm disorders, induced by these muscles.

It is proposed that in future the role of the right ventricle as the source of pulmonary emboli will become more apparent and an important part of the diagnostic work up in cases of idiopathic pulmonary embolism.

The Violin Heart

Left ventricular false tendons are thin, fibromuscular structures which traverse the left ventricular cavity. They are thought to be intracavitary radiations of the bundle of His. Usually these tendons span between the interventricular septum and the lateral wall or a papillary muscle. They have been known to be a source of innocent and musical murmurs.

In this case report a peculiar left ventricular false tendon is shown—one extending between the two papillary muscles, giving the appearance of a musical note. During ventricular diastole the tendon is pulled taut between the two heads of the papillary muscles and during ventricular systole the tendon relaxes. The echocardiographic characteristics and possible long term implications are discussed.

The violin heart

Left ventricular false tendons are thin, fibromuscular structures which traverse the left ventricular cavity. They are thought to be intracavitary radiations of the bundle of His. Usually these tendons span between the interventricular septum and the lateral wall or a papillary muscle. They have been known to be a source of innocent and musical murmurs.In this case report a peculiar left ventricular false tendon is shown-one extending between the two papillary muscles, giving the appearance of a musical note. During ventricular diastole the tendon is pulled taut between the two heads of the papillary muscles and during ventricular systole the tendon relaxes. The echocardiographic characteristics and possible long term implications are discussed.

Bigeminy and the bifid papillary muscle

Various structural anomalies of the left ventricular papillary muscles have been observed in recent years. Many of these have been linked to electrocardiographic aberrations. Recently two reports have appeared where the base of the posterior papillary muscle was identified as the source of frequent premature ventricular complexes. In some of these patients these frequent premature ventricular complexes have led to left ventricular dysfunction. In this report a newly discovered structural variant of the anterior papillary muscle is described--the bifid papillary muscle. Furthermore, it is proposed that this bifid papillary muscle is the source of frequent ventricular premature complexes, presenting as bigeminy in a patient with normal left ventricular function.

Structural causes of right bundle branch block-time for a closer look?

Right bundle branch block is an electrocardiographic phenomenon with specific criteria.

Currently, two specific forms of right bundle branch block are acknowledged, a proximal and a distal variant. A vast array of pathologies can cause proximal, distal or even combined forms of right bundle branch block.

In this study it is suggested that a third type of right bundle branch block exist: one caused by a subaortic muscular tendon in the left ventricle, leading to an increased velocity of conduction in the left ventricle, with a resultant “relative” right bundle branch block. It is concluded that it is necessary (and time) to take a closer look at endoventricular structures in the assessment of structural causes of right bundle branch block.

The Double U Wave—Should the Electrocardiogram be Interpreted Echocardiographically?

The U wave is still an electrocardiographic deflection of enigmatic origin. Numerous hypotheses on its origin have been formulated, but to date none has been conclusively proven. Recently, a report described the first case of bifid (or notched) U waves. Until then this phenomenon has only been described in the T wave. This is the first report of double U waves—two separate deflections, ascribed to an accessory papillary muscle.

The accessory papillary muscle with inferior J-waves--peculiarity or hidden danger?

Originally described in 1953, today the so-called J-wave is the source of much controversy. As a marker of so-called "early repolarization", this variant has been regarded as a totally benign variant since the 1960's. However, since then a wealth of data have indicated that the J-wave may be a marker of a highly arrhythmogenic substrate with a resultant high risk of sudden cardiac death.

In this case report a case of an accessory papillary muscle with a prominent J-wave is described. This may be the first of many possible cases where papillary muscle variants may be the cause of the J-wave.

The Brody effect induced by premature ventricular complexes in the ovine heart

The QRS response of the electrocardiogram to bleeding has been a source of interest to the physiologist for more than a century. Studies in the dog, cat and chicken have shown a reduction in QRS amplitude in response to bleeding. This effect has been explained by the so-called Brody effect, in which the intraventricular mass of blood acts as a conducting medium, augmenting radial conduction, thus resulting in the subsequent reduction in QRS amplitude in conditions where the intraventricular mass of blood is reduced. The aim of this study was to evaluate whether the Brody effect will be present in the ovine heart and, furthermore, to evaluate if the right and left ventricles will demonstrate the same QRS change if the Brody effect is indeed present. This study clearly demonstrated that the Brody effect is present in the ovine heart. Furthermore, two unique aspects emanating from this study are firstly the fact that this is the first study to show that premature ventricular complexes are able to induce the Brody effect and, secondly that there is a very clear difference in the response of the right and the left ventricles when the Brody effect is induced in the ovine heart.